Add dmd 2.075.0 support

std.algorithm.mutation copy is unable to copy a char range into a char array slice.

.editorconfig

@@ -0,0 +1,9 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+charset = utf-8
+indent_style = space
+indent_size = 4
+trim_trailing_whitespace = true

.gitignore

@@ -1,2 +1,14 @@
+# Binary
+*.[oa]
+*.exe
+
+# D
 .dub
 __test__*__
+__test__*__.core
+/tanya-test-library*
+
+/docs/
+/docs.json
+
+/*.lst

.travis.yml

@@ -0,0 +1,38 @@
+sudo: false
+
+os:
+  - linux
+  - osx
+
+language: d
+
+d:
+  - dmd-2.075.0
+  - dmd-2.074.1
+  - dmd-2.073.2
+  - dmd-2.072.2
+  - dmd-2.071.2
+
+env: 
+  matrix:
+    - ARCH=x86_64
+    - ARCH=x86
+
+addons:
+  apt:
+    packages:
+      - gcc-multilib
+
+before_script:
+  - if [ "$PS1" = '(dmd-2.075.0)' ]; then
+      export UNITTEST="unittest-cov";
+    fi
+
+script:
+  - dub test -b ${UNITTEST:-unittest} --arch=$ARCH --compiler=$DC
+  - if [ "$UNITTEST" = "unittest-cov" -a "$ARCH" = "x86_64" -a "$TRAVIS_OS_NAME" = "linux" ]; then
+      dub fetch dscanner && dub run dscanner -- -Isource --styleCheck;
+    fi
+
+after_success:
+  - test "$UNITTEST" = "unittest-cov" && bash <(curl -s https://codecov.io/bash)

CODE_OF_CONDUCT.md

@@ -0,0 +1,5 @@
+# Contributor Code of Conduct
+
+This project adheres to No Code of Conduct.  We are all adults.  We accept anyone's contributions.  Nothing else matters.
+
+For more information please visit the [No Code of Conduct](https://github.com/domgetter/NCoC) homepage.

CONTRIBUTING.md

@@ -0,0 +1,92 @@
+# Contributing
+
+Tanya is a project in active development, therefore any help is appreciated. Thank you for considering contributing
+to it, feel welcome.
+These guidelines describe ways to get started.
+
+
+## Ways to get involved
+
+* **Reporting a problem**: [Report](https://issues.caraus.io/projects/tanya/issues) bugs and usage problems you
+encounter.
+* **Fixing issues**: [The bug tracker](https://issues.caraus.io/projects/tanya/issues) contains a list of issues you
+can work on.
+* **Documentation**: You can improve API documentation by correcting grammar errors, completing existing texts and
+writing new ones, or providing usage examples.
+* **Testing**: Test coverage is important for a library. Writing tests is not only helpful, but is also a great way
+to get a feel for how tanya works.
+* **Adding new features**: Tanya is a growing library. If you think some feature is missing, you can suggest
+and implement this.
+
+
+## Opening an issue
+
+If you have found a bug, an error, have some question, or suggestion, open in issue. I'll try to answer as soon
+as I can. Tanya uses an external
+[bug tracker](https://issues.caraus.io/projects/tanya/issues). You should
+[register](https://issues.caraus.io/account/register) before you can report your issue. There is also a list
+of open issues that mirror the current development process and progress. If you're looking for a challenge, just
+pick an issue you are interested in and start working on it. Fill free to comment on the issue to get more
+information.
+
+Some issues have a category assigned to them. Such issues belong mostly to a larger part of the library that is
+currently in development. The category specifies then the git branch development happens on. The remaining issues
+can be fixed directly in master.
+
+In the [roadmap](https://issues.caraus.io/projects/tanya/roadmap) you can find a list of issues that are planned
+to be fixed till a specific release. Version numbers refer to the versions in the
+[git repository](https://github.com/caraus-ecms/tanya/releases).
+
+
+## Contribution process
+
+### Creating a pull request
+
+I accept GitHub pull requests. Creating a pull request is like sending a patch with the suggested change.
+First you have to [fork](https://guides.github.com/activities/forking/) the repository. Clone your fork locally
+with `git clone` and create a new branch where you want to work, for example:
+
+```shell
+git checkout -b bugfix-x
+```
+Commit your changes to your fork:
+
+```shell
+git commit -m "Fix X"
+git push -u origin bugfix-x
+```
+
+After that if you visit your fork on GitHub, GitHub will suggest to create pull request. Just follow the steps
+described on GitHub to finish the process. See
+[Using Pull Requests](https://help.github.com/articles/about-pull-requests/) for more information.
+
+Please ensure that your fork is even with the upstream (original) repository. If not, you have to rebase your branch
+on upstream/master before submitting a pull request. See https://help.github.com/articles/syncing-a-fork/ for a
+step-by-step guide.
+
+### Fixing a bug
+
+Add an unittest that demonstrates the bug along with a short description:
+
+```d
+// Issue ###: https://issues.caraus.io/issues/###.
+private unittest
+{
+}
+```
+
+### Adding new features
+
+* Use Ddoc to document the feature.
+* Add some unittests that prevent new bugs and demonstrate how the feature is supposed to work.
+
+### Style guide
+
+Make sure your changes follow [The D Style](https://dlang.org/dstyle.html) (including
+[Additional Requirements for Phobos](https://dlang.org/dstyle.html#phobos).
+
+
+## Questions and suggestions
+
+* [Open an issue](https://issues.caraus.io/projects/tanya/issues)
+* [Send an email](mailto:info@caraus.de)

README.md

@@ -0,0 +1,177 @@
+# Tanya
+
+[![Build status](https://travis-ci.org/caraus-ecms/tanya.svg?branch=master)](https://travis-ci.org/caraus-ecms/tanya)
+[![Build status](https://ci.appveyor.com/api/projects/status/djkmverdfsylc7ti/branch/master?svg=true)](https://ci.appveyor.com/project/belka-ew/tanya/branch/master)
+[![codecov](https://codecov.io/gh/caraus-ecms/tanya/branch/master/graph/badge.svg)](https://codecov.io/gh/caraus-ecms/tanya)
+[![Dub version](https://img.shields.io/dub/v/tanya.svg)](https://code.dlang.org/packages/tanya)
+[![Dub downloads](https://img.shields.io/dub/dt/tanya.svg)](https://code.dlang.org/packages/tanya)
+[![License](https://img.shields.io/badge/license-MPL_2.0-blue.svg)](https://raw.githubusercontent.com/caraus-ecms/tanya/master/LICENSE)
+
+Tanya is a general purpose library for D programming language.
+
+Its aim is to simplify the manual memory management in D and to provide a
+guarantee with @nogc attribute that there are no hidden allocations on the
+Garbage Collector heap. Everything in the library is usable in @nogc code.
+Tanya extends Phobos functionality and provides alternative implementations for
+data structures and utilities that depend on the Garbage Collector in Phobos.
+
+* [Bug tracker](https://issues.caraus.io/projects/tanya/issues)
+* [Documentation](https://docs.caraus.io/tanya)
+* [Contribution guidelines](CONTRIBUTING.md)
+
+
+## Overview
+
+Tanya consists of the following packages and (top-level) modules:
+
+* `async`: Event loop (epoll, kqueue and IOCP).
+* `container`: Queue, Array, Singly and doubly linked lists, Buffers, UTF-8
+string, Hash set.
+* `format`: Formatting and conversion functions.
+* `math`: Arbitrary precision integer and a set of functions.
+* `memory`: Tools for manual memory management (allocators, smart pointers).
+* `net`: URL-Parsing, network programming.
+* `network`: Socket implementation. `network` is currently under rework.
+After finishing the new socket implementation will land in the `net` package and
+`network` will be deprecated.
+* `os`: Platform-independent interfaces to operating system functionality.
+* `typecons`: Templates that allow to build new types based on the available
+ones.
+
+
+## Basic usage
+
+### Allocators
+
+Memory management is done with allocators. Instead of using `new` to create an
+instance of a class, an allocator is used:
+
+```d
+import tanya.memory;
+
+class A
+{
+    this(int arg)
+    {
+    }
+}
+
+A a = defaultAllocator.make!A(5);
+
+defaultAllocator.dispose(a);
+```
+
+As you can see, the user is responsible for deallocation, therefore `dispose`
+is called at the end.
+
+If you want to change the `defaultAllocator` to something different, you
+probably want to do it at the program's beginning. Or you can invoke another
+allocator directly. It is important to ensure that the object is destroyed
+using the same allocator that was used to allocate it.
+
+What if I get an allocated object from some function? The generic rule is: If
+you haven't requested the memory yourself (with `make`), you don't need to free
+it.
+
+`tanya.memory.smartref` contains smart pointers, helpers that can take care of
+a proper deallocation in some cases for you.
+
+### Exceptions
+
+Since exceptions are normal classes in D, they are allocated and dellocated the
+same as described above, but:
+
+1. The caller is **always** responsible for destroying a caught exception.
+2. Exceptions are **always** allocated and should be always allocated with the
+`defaultAllocator`.
+
+```d
+import tanya.memory;
+
+void functionThatThrows()
+{
+    throw defaultAlocator.make!Exception("An error occurred");
+}
+
+try
+{
+    functionThatThrows()
+}
+catch (Exception e)
+{
+    defaultAllocator.dispose(e);
+}
+```
+
+### Containers
+
+Arrays are commonly used in programming. D's built-in arrays often rely on the
+GC. It is inconvenient to change their size, reserve memory for future use and
+so on. Containers can help here. The following example demonstrates how
+`tanya.container.array.Array` can be used instead of `int[]`.
+
+```d
+import tanya.container.array;
+
+Array!int arr;
+
+// Reserve memory if I know that my container will contain approximately 15
+// elements.
+arr.reserve(15);
+
+arr.insertBack(5); // Add one element.
+arr.length = 10; // New elements are initialized to 0.
+
+// Iterate over the first five elements.
+foreach (el; arr[0 .. 5])
+{
+}
+
+int i = arr[7]; // Access 7th element.
+```
+
+There are more containers in the `tanya.container` package.
+
+
+## Development
+
+### Supported compilers
+
+| dmd     |
+|:-------:|
+| 2.075.0 |
+| 2.074.1 |
+| 2.073.2 |
+| 2.072.2 |
+| 2.071.2 |
+
+### Current status
+
+Following modules are under development:
+
+| Feature  | Branch    | Build status                                                                                                                                                                                                                                                                                  |
+|----------|:---------:|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| BitArray | bitvector | [![bitvector](https://travis-ci.org/caraus-ecms/tanya.svg?branch=bitvector)](https://travis-ci.org/caraus-ecms/tanya) [![bitvector](https://ci.appveyor.com/api/projects/status/djkmverdfsylc7ti/branch/bitvector?svg=true)](https://ci.appveyor.com/project/belka-ew/tanya/branch/bitvector) |
+| TLS      | crypto    | [![crypto](https://travis-ci.org/caraus-ecms/tanya.svg?branch=crypto)](https://travis-ci.org/caraus-ecms/tanya) [![crypto](https://ci.appveyor.com/api/projects/status/djkmverdfsylc7ti/branch/crypto?svg=true)](https://ci.appveyor.com/project/belka-ew/tanya/branch/crypto)                |
+| File IO  | io        | [![io](https://travis-ci.org/caraus-ecms/tanya.svg?branch=io)](https://travis-ci.org/caraus-ecms/tanya) [![io](https://ci.appveyor.com/api/projects/status/djkmverdfsylc7ti/branch/io?svg=true)](https://ci.appveyor.com/project/belka-ew/tanya/branch/io)                                    |
+
+### Release management
+
+3-week release cycle.
+
+Deprecated features are removed after one release (in approximately 6 weeks after deprecating).
+
+## Further characteristics
+
+* Tanya is a native D library without any external dependencies.
+
+* Tanya is cross-platform. The development happens on a 64-bit Linux, but it
+is being tested on Windows and FreeBSD as well.
+
+* The library isn't thread-safe yet.
+
+
+## Feedback
+
+Any feedback about your experience with tanya would be greatly appreciated. Feel free to
+[contact me](mailto:info@caraus.de).

appveyor.yml

@@ -0,0 +1,78 @@
+platform: x64
+os: Visual Studio 2015
+
+environment:
+  matrix:
+    - DC: dmd
+      DVersion: 2.075.0
+      arch: x64
+    - DC: dmd
+      DVersion: 2.075.0
+      arch: x86
+    - DC: dmd
+      DVersion: 2.074.1
+      arch: x64
+    - DC: dmd
+      DVersion: 2.074.1
+      arch: x86
+    - DC: dmd
+      DVersion: 2.073.2
+      arch: x64
+    - DC: dmd
+      DVersion: 2.073.2
+      arch: x86
+    - DC: dmd
+      DVersion: 2.072.2
+      arch: x64
+    - DC: dmd
+      DVersion: 2.072.2
+      arch: x86
+    - DC: dmd
+      DVersion: 2.071.2
+      arch: x64
+    - DC: dmd
+      DVersion: 2.071.2
+      arch: x86
+
+skip_tags: true
+
+install:
+  - ps: function SetUpDCompiler
+        {
+          $env:toolchain = "msvc";
+          $version = $env:DVersion;
+          Invoke-WebRequest "http://downloads.dlang.org/releases/2.x/$($version)/dmd.$($version).windows.7z" -OutFile "c:\dmd.7z";
+          echo "finished.";
+          pushd c:\\;
+          7z x dmd.7z > $null;
+          popd;
+        }
+  - ps: SetUpDCompiler
+
+  - ps: if($env:DVersion -eq "2.071.2"){
+          Invoke-WebRequest "http://code.dlang.org/files/dub-1.2.1-windows-x86.zip" -OutFile "dub.zip";
+          7z x dub.zip -odub > $null;
+          Move-Item "dub/dub.exe" "C:\dmd2\windows\bin"
+        }
+
+before_build:
+  - ps: if($env:arch -eq "x86"){
+          $env:compilersetupargs = "x86";
+          $env:Darch = "x86";
+        }
+        elseif($env:arch -eq "x64"){
+          $env:compilersetupargs = "amd64";
+          $env:Darch = "x86_64";
+        }
+  - ps: $env:PATH += ";C:\dmd2\windows\bin;";
+  - call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall" %compilersetupargs%
+
+build_script:
+  - echo dummy build script - dont remove me
+
+test_script:
+  - echo %Darch%
+  - echo %PATH%
+  - 'dub --version'
+  - '%DC% --version'
+  - dub test -b unittest --arch=%Darch% --compiler=%DC%

codecov.yml

@@ -0,0 +1,3 @@
+ignore:
+  - "source/tanya/async/event/iocp.d"
+  - "source/tanya/async/iocp.d"

dscanner.ini

@@ -0,0 +1,81 @@
+; Configure which static analysis checks are skip-unittest
+[analysis.config.StaticAnalysisConfig]
+; Check variable, class, struct, interface, union, and function names against t
+; he Phobos style guide
+style_check="disabled"
+; Check for array literals that cause unnecessary allocation
+enum_array_literal_check="skip-unittest"
+; Check for poor exception handling practices
+exception_check="skip-unittest"
+; Check for use of the deprecated 'delete' keyword
+delete_check="skip-unittest"
+; Check for use of the deprecated floating point operators
+float_operator_check="skip-unittest"
+; Check number literals for readability
+number_style_check="disabled"
+; Checks that opEquals, opCmp, toHash, and toString are either const, immutable
+; , or inout.
+object_const_check="disabled"
+; Checks for .. expressions where the left side is larger than the right.
+backwards_range_check="skip-unittest"
+; Checks for if statements whose 'then' block is the same as the 'else' block
+if_else_same_check="skip-unittest"
+; Checks for some problems with constructors
+constructor_check="skip-unittest"
+; Checks for unused variables and function parameters
+unused_variable_check="disabled"
+; Checks for unused labels
+unused_label_check="skip-unittest"
+; Checks for duplicate attributes
+duplicate_attribute="skip-unittest"
+; Checks that opEquals and toHash are both defined or neither are defined
+opequals_tohash_check="disabled"
+; Checks for subtraction from .length properties
+length_subtraction_check="disabled"
+; Checks for methods or properties whose names conflict with built-in propertie
+; s
+builtin_property_names_check="skip-unittest"
+; Checks for confusing code in inline asm statements
+asm_style_check="skip-unittest"
+; Checks for confusing logical operator precedence
+logical_precedence_check="skip-unittest"
+; Checks for undocumented public declarations
+undocumented_declaration_check="disabled"
+; Checks for poor placement of function attributes
+function_attribute_check="skip-unittest"
+; Checks for use of the comma operator
+comma_expression_check="skip-unittest"
+; Checks for local imports that are too broad
+local_import_check="disabled"
+; Checks for variables that could be declared immutable
+could_be_immutable_check="disabled"
+; Checks for redundant expressions in if statements
+redundant_if_check="skip-unittest"
+; Checks for redundant parenthesis
+redundant_parens_check="skip-unittest"
+; Checks for mismatched argument and parameter names
+mismatched_args_check="skip-unittest"
+; Checks for labels with the same name as variables
+label_var_same_name_check="disabled"
+; Checks for lines longer than 120 characters
+long_line_check="skip-unittest"
+; Checks for assignment to auto-ref function parameters
+auto_ref_assignment_check="disabled"
+; Checks for incorrect infinite range definitions
+incorrect_infinite_range_check="skip-unittest"
+; Checks for asserts that are always true
+useless_assert_check="skip-unittest"
+; Check for uses of the old-style alias syntax
+alias_syntax_check="disabled"
+; Checks for else if that should be else static if
+static_if_else_check="skip-unittest"
+; Check for unclear lambda syntax
+lambda_return_check="skip-unittest"
+; Check for auto function without return statement
+auto_function_check="skip-unittest"
+; Check for sortedness of imports
+imports_sortedness="disabled"
+; Check for explicitly annotated unittests
+explicitly_annotated_unittests="disabled"
+; Check for useless usage of the final attribute
+final_attribute_check="skip-unittest"

dub.json

@@ -1,6 +1,6 @@
 {
 	"name": "tanya",
-	"description": "D library with event loop",
+	"description": "General purpose, @nogc library. Containers, networking, memory management, utilities",
 	"license": "MPL-2.0",
 	"copyright": "(c) Eugene Wissner <info@caraus.de>",
 	"authors": [

source/tanya/async/event/epoll.d

@@ -0,0 +1,186 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Event loop implementation for Linux.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.event.epoll;
+
+version (D_Ddoc)
+{
+}
+else version (linux):
+
+public import core.sys.linux.epoll;
+import tanya.async.protocol;
+import tanya.async.event.selector;
+import tanya.async.loop;
+import tanya.async.transport;
+import tanya.async.watcher;
+import tanya.container.array;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+import core.stdc.errno;
+import core.sys.posix.unistd;
+import core.time;
+import std.algorithm.comparison;
+
+extern (C) nothrow @nogc
+{
+    int epoll_create1(int flags);
+    int epoll_ctl (int epfd, int op, int fd, epoll_event *event);
+    int epoll_wait (int epfd, epoll_event *events, int maxevents, int timeout);
+}
+
+final class EpollLoop : SelectorLoop
+{
+    protected int fd;
+    private Array!epoll_event events;
+
+    /**
+     * Initializes the loop.
+     */
+    this() @nogc
+    {
+        if ((fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
+        {
+            throw defaultAllocator.make!BadLoopException("epoll initialization failed");
+        }
+        super();
+        events = Array!epoll_event(maxEvents, MmapPool.instance);
+    }
+
+    /**
+     * Frees loop internals.
+     */
+    ~this() @nogc
+    {
+        close(fd);
+    }
+
+    /**
+     * Should be called if the backend configuration changes.
+     *
+     * Params:
+     *  watcher   = Watcher.
+     *  oldEvents = The events were already set.
+     *  events    = The events should be set.
+     *
+     * Returns: $(D_KEYWORD true) if the operation was successful.
+     */
+    protected override bool reify(SocketWatcher watcher,
+                                  EventMask oldEvents,
+                                  EventMask events) @nogc
+    {
+        int op = EPOLL_CTL_DEL;
+        epoll_event ev;
+
+        if (events == oldEvents)
+        {
+            return true;
+        }
+        if (events && oldEvents)
+        {
+            op = EPOLL_CTL_MOD;
+        }
+        else if (events && !oldEvents)
+        {
+            op = EPOLL_CTL_ADD;
+        }
+
+        ev.data.fd = watcher.socket.handle;
+        ev.events = (events & (Event.read | Event.accept) ? EPOLLIN | EPOLLPRI : 0)
+                  | (events & Event.write ? EPOLLOUT : 0)
+                  | EPOLLET;
+
+        return epoll_ctl(fd, op, watcher.socket.handle, &ev) == 0;
+    }
+
+    /**
+     * Does the actual polling.
+     */
+    protected override void poll() @nogc
+    {
+        // Don't block
+        immutable timeout = cast(immutable int) blockTime.total!"msecs";
+        auto eventCount = epoll_wait(fd, events.get().ptr, maxEvents, timeout);
+
+        if (eventCount < 0)
+        {
+            if (errno != EINTR)
+            {
+                throw defaultAllocator.make!BadLoopException();
+            }
+            return;
+        }
+
+        for (auto i = 0; i < eventCount; ++i)
+        {
+            auto transport = cast(StreamTransport) connections[events[i].data.fd];
+
+            if (transport is null)
+            {
+                auto connection = cast(ConnectionWatcher) connections[events[i].data.fd];
+                assert(connection !is null);
+
+                acceptConnections(connection);
+            }
+            else if (events[i].events & EPOLLERR)
+            {
+                kill(transport);
+                continue;
+            }
+            else if (events[i].events & (EPOLLIN | EPOLLPRI | EPOLLHUP))
+            {
+                SocketException exception;
+                try
+                {
+                    ptrdiff_t received;
+                    do
+                    {
+                        received = transport.socket.receive(transport.output[]);
+                        transport.output += received;
+                    }
+                    while (received);
+                }
+                catch (SocketException e)
+                {
+                    exception = e;
+                }
+                if (transport.socket.disconnected)
+                {
+                    kill(transport, exception);
+                    continue;
+                }
+                else if (transport.output.length)
+                {
+                    pendings.enqueue(transport);
+                }
+            }
+            if (events[i].events & EPOLLOUT)
+            {
+                transport.writeReady = true;
+                if (transport.input.length)
+                {
+                    feed(transport);
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns: The blocking time.
+     */
+    override protected @property inout(Duration) blockTime()
+    inout @safe pure nothrow
+    {
+        return min(super.blockTime, 1.dur!"seconds");
+    }
+}

source/tanya/async/event/iocp.d

@@ -0,0 +1,389 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Event loop implementation for Windows.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.event.iocp;
+
+version (D_Ddoc)
+{
+}
+else version (Windows):
+
+import tanya.container.buffer;
+import tanya.async.loop;
+import tanya.async.protocol;
+import tanya.async.transport;
+import tanya.async.watcher;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+import core.sys.windows.basetyps;
+import core.sys.windows.mswsock;
+import core.sys.windows.winbase;
+import core.sys.windows.windef;
+import core.sys.windows.winsock2;
+
+/**
+ * Transport for stream sockets.
+ */
+final class StreamTransport : SocketWatcher, DuplexTransport, SocketTransport
+{
+    private SocketException exception;
+
+    private ReadBuffer!ubyte output;
+
+    private WriteBuffer!ubyte input;
+
+    private Protocol protocol_;
+
+    private bool closing;
+
+    /**
+     * Creates new completion port transport.
+     *
+     * Params:
+     *  socket = Socket.
+     *
+     * Precondition: $(D_INLINECODE socket !is null)
+     */
+    this(OverlappedConnectedSocket socket) @nogc
+    {
+        super(socket);
+        output = ReadBuffer!ubyte(8192, 1024, MmapPool.instance);
+        input = WriteBuffer!ubyte(8192, MmapPool.instance);
+        active = true;
+    }
+
+    /**
+     * Returns: Socket.
+     *
+     * Postcondition: $(D_INLINECODE socket !is null)
+     */
+    override @property OverlappedConnectedSocket socket() pure nothrow @safe @nogc
+    out (socket)
+    {
+        assert(socket !is null);
+    }
+    body
+    {
+        return cast(OverlappedConnectedSocket) socket_;
+    }
+
+    /**
+     * Returns $(D_PARAM true) if the transport is closing or closed.
+     */
+    bool isClosing() const pure nothrow @safe @nogc
+    {
+        return closing;
+    }
+
+    /**
+     * Close the transport.
+     *
+     * Buffered data will be flushed.  No more data will be received.
+     */
+    void close() pure nothrow @safe @nogc
+    {
+        closing = true;
+    }
+
+    /**
+     * Write some data to the transport.
+     *
+     * Params:
+     *  data = Data to send.
+     */
+    void write(ubyte[] data) @nogc
+    {
+        input ~= data;
+    }
+
+    /**
+     * Returns: Application protocol.
+     */
+    @property Protocol protocol() pure nothrow @safe @nogc
+    {
+        return protocol_;
+    }
+
+    /**
+     * Switches the protocol.
+     *
+     * The protocol is deallocated by the event loop, it should currently be
+     * allocated with $(D_PSYMBOL MmapPool).
+     *
+     * Params:
+     *  protocol = Application protocol.
+     *
+     * Precondition: $(D_INLINECODE protocol !is null)
+     */
+    @property void protocol(Protocol protocol) pure nothrow @safe @nogc
+    in
+    {
+        assert(protocol !is null);
+    }
+    body
+    {
+        protocol_ = protocol;
+    }
+
+    /**
+     * Invokes the watcher callback.
+     */
+    override void invoke() @nogc
+    {
+        if (output.length)
+        {
+            immutable empty = input.length == 0;
+            protocol.received(output[0 .. $]);
+            output.clear();
+            if (empty)
+            {
+                SocketState overlapped;
+                try
+                {
+                    overlapped = MmapPool.instance.make!SocketState;
+                    socket.beginSend(input[], overlapped);
+                }
+                catch (SocketException e)
+                {
+                    MmapPool.instance.dispose(overlapped);
+                    MmapPool.instance.dispose(e);
+                }
+            }
+        }
+        else
+        {
+            protocol.disconnected(exception);
+            MmapPool.instance.dispose(protocol_);
+            defaultAllocator.dispose(exception);
+            active = false;
+        }
+    }
+}
+
+final class IOCPLoop : Loop
+{
+    protected HANDLE completionPort;
+
+    protected OVERLAPPED overlap;
+
+    /**
+     * Initializes the loop.
+     */
+    this() @nogc
+    {
+        super();
+
+        completionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0);
+        if (!completionPort)
+        {
+            throw make!BadLoopException(defaultAllocator,
+                                        "Creating completion port failed");
+        }
+    }
+
+    /**
+     * Should be called if the backend configuration changes.
+     *
+     * Params:
+     *  watcher   = Watcher.
+     *  oldEvents = The events were already set.
+     *  events    = The events should be set.
+     *
+     * Returns: $(D_KEYWORD true) if the operation was successful.
+     */
+    override protected bool reify(SocketWatcher watcher,
+                                  EventMask oldEvents,
+                                  EventMask events) @nogc
+    {
+        SocketState overlapped;
+        if (!(oldEvents & Event.accept) && (events & Event.accept))
+        {
+            auto socket = cast(OverlappedStreamSocket) watcher.socket;
+            assert(socket !is null);
+
+            if (CreateIoCompletionPort(cast(HANDLE) socket.handle,
+                                       completionPort,
+                                       cast(ULONG_PTR) (cast(void*) watcher),
+                                       0) !is completionPort)
+            {
+                return false;
+            }
+
+            try
+            {
+                overlapped = MmapPool.instance.make!SocketState;
+                socket.beginAccept(overlapped);
+            }
+            catch (SocketException e)
+            {
+                MmapPool.instance.dispose(overlapped);
+                defaultAllocator.dispose(e);
+                return false;
+            }
+        }
+        if ((!(oldEvents & Event.read) && (events & Event.read))
+            || (!(oldEvents & Event.write) && (events & Event.write)))
+        {
+            auto transport = cast(StreamTransport) watcher;
+            assert(transport !is null);
+
+            if (CreateIoCompletionPort(cast(HANDLE) transport.socket.handle,
+                                       completionPort,
+                                       cast(ULONG_PTR) (cast(void*) watcher),
+                                       0) !is completionPort)
+            {
+                return false;
+            }
+
+            // Begin to read
+            if (!(oldEvents & Event.read) && (events & Event.read))
+            {
+                try
+                {
+                    overlapped = MmapPool.instance.make!SocketState;
+                    transport.socket.beginReceive(transport.output[], overlapped);
+                }
+                catch (SocketException e)
+                {
+                    MmapPool.instance.dispose(overlapped);
+                    defaultAllocator.dispose(e);
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+
+    private void kill(StreamTransport transport,
+                      SocketException exception = null) @nogc
+    in
+    {
+        assert(transport !is null);
+    }
+    body
+    {
+        transport.socket.shutdown();
+        defaultAllocator.dispose(transport.socket);
+        transport.exception = exception;
+        pendings.enqueue(transport);
+    }
+
+    /**
+     * Does the actual polling.
+     */
+    override protected void poll() @nogc
+    {
+        DWORD lpNumberOfBytes;
+        ULONG_PTR key;
+        LPOVERLAPPED overlap;
+        immutable timeout = cast(immutable int) blockTime.total!"msecs";
+
+        auto result = GetQueuedCompletionStatus(completionPort,
+                                                &lpNumberOfBytes,
+                                                &key,
+                                                &overlap,
+                                                timeout);
+        if (result == FALSE && overlap == NULL)
+        {
+            return; // Timeout
+        }
+
+        auto overlapped = (cast(SocketState) ((cast(void*) overlap) - 8));
+        assert(overlapped !is null);
+        scope (failure)
+        {
+            MmapPool.instance.dispose(overlapped);
+        }
+
+        switch (overlapped.event)
+        {
+            case OverlappedSocketEvent.accept:
+                auto connection = cast(ConnectionWatcher) (cast(void*) key);
+                assert(connection !is null);
+
+                auto listener = cast(OverlappedStreamSocket) connection.socket;
+                assert(listener !is null);
+
+                auto socket = listener.endAccept(overlapped);
+                auto transport = MmapPool.instance.make!StreamTransport(socket);
+
+                connection.incoming.enqueue(transport);
+
+                reify(transport, EventMask(Event.none), EventMask(Event.read, Event.write));
+
+                pendings.enqueue(connection);
+                listener.beginAccept(overlapped);
+                break;
+            case OverlappedSocketEvent.read:
+                auto transport = cast(StreamTransport) (cast(void*) key);
+                assert(transport !is null);
+
+                if (!transport.active)
+                {
+                    MmapPool.instance.dispose(transport);
+                    MmapPool.instance.dispose(overlapped);
+                    return;
+                }
+
+                int received;
+                SocketException exception;
+                try
+                {
+                    received = transport.socket.endReceive(overlapped);
+                }
+                catch (SocketException e)
+                {
+                    exception = e;
+                }
+                if (transport.socket.disconnected)
+                {
+                    // We want to get one last notification to destroy the watcher.
+                    transport.socket.beginReceive(transport.output[], overlapped);
+                    kill(transport, exception);
+                }
+                else if (received > 0)
+                {
+                    immutable full = transport.output.free == received;
+
+                    transport.output += received;
+                    // Receive was interrupted because the buffer is full. We have to continue.
+                    if (full)
+                    {
+                        transport.socket.beginReceive(transport.output[], overlapped);
+                    }
+                    pendings.enqueue(transport);
+                }
+                break;
+            case OverlappedSocketEvent.write:
+                auto transport = cast(StreamTransport) (cast(void*) key);
+                assert(transport !is null);
+
+                transport.input += transport.socket.endSend(overlapped);
+                if (transport.input.length > 0)
+                {
+                    transport.socket.beginSend(transport.input[], overlapped);
+                }
+                else
+                {
+                    transport.socket.beginReceive(transport.output[], overlapped);
+                    if (transport.isClosing())
+                    {
+                        kill(transport);
+                    }
+                }
+                break;
+            default:
+                assert(false, "Unknown event");
+        }
+    }
+}

source/tanya/async/event/kqueue.d

@@ -0,0 +1,330 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Event loop implementation for *BSD.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.event.kqueue;
+
+version (D_Ddoc)
+{
+}
+else version (OSX)
+{
+    version = MacBSD;
+}
+else version (iOS)
+{
+    version = MacBSD;
+}
+else version (TVOS)
+{
+    version = MacBSD;
+}
+else version (WatchOS)
+{
+    version = MacBSD;
+}
+else version (FreeBSD)
+{
+    version = MacBSD;
+}
+else version (OpenBSD)
+{
+    version = MacBSD;
+}
+else version (DragonFlyBSD)
+{
+    version = MacBSD;
+}
+
+version (MacBSD):
+
+import core.stdc.errno;
+import core.sys.posix.time; // timespec
+import core.sys.posix.unistd;
+import core.time;
+import std.algorithm.comparison;
+import tanya.async.event.selector;
+import tanya.async.loop;
+import tanya.async.transport;
+import tanya.async.watcher;
+import tanya.container.array;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+
+void EV_SET(kevent_t* kevp, typeof(kevent_t.tupleof) args) pure nothrow @nogc
+{
+    *kevp = kevent_t(args);
+}
+
+enum : short
+{
+    EVFILT_READ     =  -1,
+    EVFILT_WRITE    =  -2,
+    EVFILT_AIO      =  -3, /* attached to aio requests */
+    EVFILT_VNODE    =  -4, /* attached to vnodes */
+    EVFILT_PROC     =  -5, /* attached to struct proc */
+    EVFILT_SIGNAL   =  -6, /* attached to struct proc */
+    EVFILT_TIMER    =  -7, /* timers */
+    EVFILT_MACHPORT =  -8, /* Mach portsets */
+    EVFILT_FS       =  -9, /* filesystem events */
+    EVFILT_USER     = -10, /* User events */
+    EVFILT_VM       = -12, /* virtual memory events */
+    EVFILT_SYSCOUNT =  11
+}
+
+struct kevent_t
+{
+    uintptr_t    ident; /* identifier for this event */
+    short       filter; /* filter for event */
+    ushort       flags;
+    uint        fflags;
+    intptr_t      data;
+    void        *udata; /* opaque user data identifier */
+}
+
+enum
+{
+    /* actions */
+    EV_ADD      = 0x0001, /* add event to kq (implies enable) */
+    EV_DELETE   = 0x0002, /* delete event from kq */
+    EV_ENABLE   = 0x0004, /* enable event */
+    EV_DISABLE  = 0x0008, /* disable event (not reported) */
+
+    /* flags */
+    EV_ONESHOT  = 0x0010, /* only report one occurrence */
+    EV_CLEAR    = 0x0020, /* clear event state after reporting */
+    EV_RECEIPT  = 0x0040, /* force EV_ERROR on success, data=0 */
+    EV_DISPATCH = 0x0080, /* disable event after reporting */
+
+    EV_SYSFLAGS = 0xF000, /* reserved by system */
+    EV_FLAG1    = 0x2000, /* filter-specific flag */
+
+    /* returned values */
+    EV_EOF      = 0x8000, /* EOF detected */
+    EV_ERROR    = 0x4000, /* error, data contains errno */
+}
+
+extern(C) int kqueue() nothrow @nogc;
+extern(C) int kevent(int kq, const kevent_t *changelist, int nchanges,
+                     kevent_t *eventlist, int nevents, const timespec *timeout)
+                     nothrow @nogc;
+
+final class KqueueLoop : SelectorLoop
+{
+    protected int fd;
+    private Array!kevent_t events;
+    private Array!kevent_t changes;
+    private size_t changeCount;
+
+    /**
+     * Returns: Maximal event count can be got at a time
+     *          (should be supported by the backend).
+     */
+    override protected @property uint maxEvents()
+    const pure nothrow @safe @nogc
+    {
+        return cast(uint) events.length;
+    }
+
+    this() @nogc
+    {
+        super();
+
+        if ((fd = kqueue()) == -1)
+        {
+            throw make!BadLoopException(defaultAllocator,
+                                        "kqueue initialization failed");
+        }
+        events = Array!kevent_t(64, MmapPool.instance);
+        changes = Array!kevent_t(64, MmapPool.instance);
+    }
+
+    /**
+     * Frees loop internals.
+     */
+    ~this() @nogc
+    {
+        close(fd);
+    }
+
+    private void set(SocketType socket, short filter, ushort flags) @nogc
+    {
+        if (changes.length <= changeCount)
+        {
+            changes.length = changeCount + maxEvents;
+        }
+        EV_SET(&changes[changeCount],
+               cast(ulong) socket,
+               filter,
+               flags,
+               0U,
+               0L,
+               null);
+        ++changeCount;
+    }
+
+    /**
+     * Should be called if the backend configuration changes.
+     *
+     * Params:
+     * 	watcher   = Watcher.
+     * 	oldEvents = The events were already set.
+     * 	events    = The events should be set.
+     *
+     * Returns: $(D_KEYWORD true) if the operation was successful.
+     */
+    override protected bool reify(SocketWatcher watcher,
+                                  EventMask oldEvents,
+                                  EventMask events) @nogc
+    {
+        if (events != oldEvents)
+        {
+            if (oldEvents & Event.read || oldEvents & Event.accept)
+            {
+                set(watcher.socket.handle, EVFILT_READ, EV_DELETE);
+            }
+            if (oldEvents & Event.write)
+            {
+                set(watcher.socket.handle, EVFILT_WRITE, EV_DELETE);
+            }
+        }
+        if (events & (Event.read | events & Event.accept))
+        {
+            set(watcher.socket.handle, EVFILT_READ, EV_ADD | EV_ENABLE);
+        }
+        if (events & Event.write)
+        {
+            set(watcher.socket.handle, EVFILT_WRITE, EV_ADD | EV_DISPATCH);
+        }
+        return true;
+    }
+
+    /**
+     * Does the actual polling.
+     */
+    protected override void poll() @nogc
+    {
+        timespec ts;
+        blockTime.split!("seconds", "nsecs")(ts.tv_sec, ts.tv_nsec);
+
+        if (changeCount > maxEvents) 
+        {
+            events.length = changes.length;
+        }
+
+        auto eventCount = kevent(fd,
+                                 changes.get().ptr,
+                                 cast(int) changeCount,
+                                 events.get().ptr,
+                                 maxEvents,
+                                 &ts);
+        changeCount = 0;
+
+        if (eventCount < 0)
+        {
+            if (errno != EINTR)
+            {
+                throw defaultAllocator.make!BadLoopException();
+            }
+            return;
+        }
+
+        for (int i; i < eventCount; ++i)
+        {
+            assert(connections.length > events[i].ident);
+
+            auto transport = cast(StreamTransport) connections[events[i].ident];
+            // If it is a ConnectionWatcher. Accept connections.
+            if (transport is null)
+            {
+                auto connection = cast(ConnectionWatcher) connections[events[i].ident];
+                assert(connection !is null);
+
+                acceptConnections(connection);
+            }
+            else if (events[i].flags & EV_ERROR)
+            {
+                kill(transport);
+            }
+            else if (events[i].filter == EVFILT_READ)
+            {
+                SocketException exception;
+                try
+                {
+                    ptrdiff_t received;
+                    do
+                    {
+                        received = transport.socket.receive(transport.output[]);
+                        transport.output += received;
+                    }
+                    while (received);
+                }
+                catch (SocketException e)
+                {
+                    exception = e;
+                }
+                if (transport.socket.disconnected)
+                {
+                    kill(transport, exception);
+                }
+                else if (transport.output.length)
+                {
+                    pendings.enqueue(transport);
+                }
+            }
+            else if (events[i].filter == EVFILT_WRITE)
+            {
+                transport.writeReady = true;
+                if (transport.input.length)
+                {
+                    feed(transport);
+                }
+            }
+        }
+    }
+
+    /**
+     * Returns: The blocking time.
+     */
+    override protected @property inout(Duration) blockTime()
+    inout @nogc @safe pure nothrow
+    {
+        return min(super.blockTime, 1.dur!"seconds");
+    }
+
+    /**
+     * If the transport couldn't send the data, the further sending should
+     * be handled by the event loop.
+     *
+     * Params:
+     * 	transport = Transport.
+     * 	exception = Exception thrown on sending.
+     *
+     * Returns: $(D_KEYWORD true) if the operation could be successfully
+     *          completed or scheduled, $(D_KEYWORD false) otherwise (the
+     *          transport will be destroyed then).
+     */
+    protected override bool feed(StreamTransport transport,
+                                 SocketException exception = null) @nogc
+    {
+        if (!super.feed(transport, exception))
+        {
+            return false;
+        }
+        if (!transport.writeReady)
+        {
+            set(transport.socket.handle, EVFILT_WRITE, EV_DISPATCH);
+            return true;
+        }
+        return false;
+    }
+}

source/tanya/async/event/selector.d

@@ -0,0 +1,405 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * This module contains base implementations for reactor event loops.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.event.selector;
+
+version (D_Ddoc)
+{
+}
+else version (Posix):
+
+import tanya.async.loop;
+import tanya.async.protocol;
+import tanya.async.transport;
+import tanya.async.watcher;
+import tanya.container.buffer;
+import tanya.container.array;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+
+/**
+ * Transport for stream sockets.
+ */
+package class StreamTransport : SocketWatcher, DuplexTransport, SocketTransport
+{
+    private SelectorLoop loop;
+
+    private SocketException exception;
+
+    package ReadBuffer!ubyte output;
+
+    package WriteBuffer!ubyte input;
+
+    private Protocol protocol_;
+
+    private bool closing;
+
+    /// Received notification that the underlying socket is write-ready.
+    package bool writeReady;
+
+    /**
+     * Params:
+     *  loop   = Event loop.
+     *  socket = Socket.
+     *
+     * Precondition: $(D_INLINECODE loop !is null && socket !is null)
+     */
+    this(SelectorLoop loop, ConnectedSocket socket) @nogc
+    in 
+    {
+        assert(loop !is null);
+    }
+    body
+    {
+        super(socket);
+        this.loop = loop;
+        output = ReadBuffer!ubyte(8192, 1024, MmapPool.instance);
+        input = WriteBuffer!ubyte(8192, MmapPool.instance);
+        active = true;
+    }
+
+    /**
+     * Returns: Socket.
+     *
+     * Postcondition: $(D_INLINECODE socket !is null)
+     */
+    override @property ConnectedSocket socket() pure nothrow @safe @nogc
+    out (socket)
+    {
+        assert(socket !is null);
+    }
+    body
+    {
+        return cast(ConnectedSocket) socket_;
+    }
+
+    private @property void socket(ConnectedSocket socket)
+    pure nothrow @safe @nogc
+    in
+    {
+        assert(socket !is null);
+    }
+    body
+    {
+        socket_ = socket;
+    }
+
+    /**
+     * Returns: Application protocol.
+     */
+    @property Protocol protocol() pure nothrow @safe @nogc
+    {
+        return protocol_;
+    }
+
+    /**
+     * Switches the protocol.
+     *
+     * The protocol is deallocated by the event loop, it should currently be
+     * allocated with $(D_PSYMBOL MmapPool).
+     *
+     * Params:
+     *  protocol = Application protocol.
+     *
+     * Precondition: $(D_INLINECODE protocol !is null)
+     */
+    @property void protocol(Protocol protocol) pure nothrow @safe @nogc
+    in
+    {
+        assert(protocol !is null);
+    }
+    body
+    {
+        protocol_ = protocol;
+    }
+
+    /**
+     * Returns $(D_PARAM true) if the transport is closing or closed.
+     */
+    bool isClosing() const pure nothrow @safe @nogc
+    {
+        return closing;
+    }
+
+    /**
+     * Close the transport.
+     *
+     * Buffered data will be flushed.  No more data will be received.
+     */
+    void close() @nogc
+    {
+        closing = true;
+        loop.reify(this,
+                   EventMask(Event.read, Event.write),
+                   EventMask(Event.write));
+    }
+
+    /**
+     * Invokes the watcher callback.
+     */
+    override void invoke() @nogc
+    {
+        if (output.length)
+        {
+            protocol.received(output[0 .. $]);
+            output.clear();
+            if (isClosing() && input.length == 0)
+            {
+                loop.kill(this);
+            }
+        }
+        else
+        {
+            protocol.disconnected(exception);
+            MmapPool.instance.dispose(protocol_);
+            defaultAllocator.dispose(exception);
+            active = false;
+        }
+    }
+
+    /**
+     * Write some data to the transport.
+     *
+     * Params:
+     *  data = Data to send.
+     */
+    void write(ubyte[] data) @nogc
+    {
+        if (!data.length)
+        {
+            return;
+        }
+        // Try to write if the socket is write ready.
+        if (writeReady)
+        {
+            ptrdiff_t sent;
+            SocketException exception;
+            try
+            {
+                sent = socket.send(data);
+                if (sent == 0)
+                {
+                    writeReady = false;
+                }
+            }
+            catch (SocketException e)
+            {
+                writeReady = false;
+                exception = e;
+            }
+            if (sent < data.length)
+            {
+                input ~= data[sent..$];
+                loop.feed(this, exception);
+            }
+        }
+        else
+        {
+            input ~= data;
+        }
+    }
+}
+
+abstract class SelectorLoop : Loop
+{
+    /// Pending connections.
+    protected Array!SocketWatcher connections;
+
+    this() @nogc
+    {
+        super();
+        connections = Array!SocketWatcher(maxEvents, MmapPool.instance);
+    }
+
+    ~this() @nogc
+    {
+        foreach (ref connection; connections)
+        {
+            // We want to free only the transports. ConnectionWatcher are
+            // created by the user and should be freed by himself.
+            if (cast(StreamTransport) connection !is null)
+            {
+                MmapPool.instance.dispose(connection);
+            }
+        }
+    }
+
+    /**
+     * Should be called if the backend configuration changes.
+     *
+     * Params:
+     *  watcher   = Watcher.
+     *  oldEvents = The events were already set.
+     *  events    = The events should be set.
+     *
+     * Returns: $(D_KEYWORD true) if the operation was successful.
+     */
+    override abstract protected bool reify(SocketWatcher watcher,
+                                           EventMask oldEvents,
+                                           EventMask events) @nogc;
+
+    /**
+     * Kills the watcher and closes the connection.
+     *
+     * Params:
+     *  transport = Transport.
+     *  exception = Occurred exception.
+     */
+    protected void kill(StreamTransport transport,
+                        SocketException exception = null) @nogc
+    in
+    {
+        assert(transport !is null);
+    }
+    body
+    {
+        transport.socket.shutdown();
+        defaultAllocator.dispose(transport.socket);
+        transport.exception = exception;
+        pendings.enqueue(transport);
+    }
+
+    /**
+     * If the transport couldn't send the data, the further sending should
+     * be handled by the event loop.
+     *
+     * Params:
+     *  transport = Transport.
+     *  exception = Exception thrown on sending.
+     *
+     * Returns: $(D_KEYWORD true) if the operation could be successfully
+     *          completed or scheduled, $(D_KEYWORD false) otherwise (the
+     *          transport will be destroyed then).
+     */
+    protected bool feed(StreamTransport transport,
+                        SocketException exception = null) @nogc
+    in
+    {
+        assert(transport !is null);
+    }
+    body
+    {
+        while (transport.input.length && transport.writeReady)
+        {
+            try
+            {
+                ptrdiff_t sent = transport.socket.send(transport.input[]);
+                if (sent == 0)
+                {
+                    transport.writeReady = false;
+                }
+                else
+                {
+                    transport.input += sent;
+                }
+            }
+            catch (SocketException e)
+            {
+                exception = e;
+                transport.writeReady = false;
+            }
+        }
+        if (exception !is null)
+        {
+            kill(transport, exception);
+            return false;
+        }
+        if (transport.input.length == 0 && transport.isClosing())
+        {
+            kill(transport);
+        }
+        return true;
+    }
+
+    /**
+     * Start watching.
+     *
+     * Params:
+     *  watcher = Watcher.
+     */
+    override void start(ConnectionWatcher watcher) @nogc
+    {
+        if (watcher.active)
+        {
+            return;
+        }
+
+        if (connections.length <= watcher.socket)
+        {
+            connections.length = watcher.socket.handle + maxEvents / 2;
+        }
+        connections[watcher.socket.handle] = watcher;
+
+        super.start(watcher);
+    }
+
+    /**
+     * Accept incoming connections.
+     *
+     * Params:
+     *  connection = Connection watcher ready to accept.
+     */
+    package void acceptConnections(ConnectionWatcher connection) @nogc
+    in
+    {
+        assert(connection !is null);
+    }
+    body
+    {
+        while (true)
+        {
+            ConnectedSocket client;
+            try
+            {
+                client = (cast(StreamSocket) connection.socket).accept();
+            }
+            catch (SocketException e)
+            {
+                defaultAllocator.dispose(e);
+                break;
+            }
+            if (client is null)
+            {
+                break;
+            }
+
+            StreamTransport transport;
+
+            if (connections.length > client.handle)
+            {
+                transport = cast(StreamTransport) connections[client.handle];
+            }
+            else
+            {
+                connections.length = client.handle + maxEvents / 2;
+            }
+            if (transport is null)
+            {
+                transport = MmapPool.instance.make!StreamTransport(this, client);
+                connections[client.handle] = transport;
+            }
+            else
+            {
+                transport.socket = client;
+            }
+
+            reify(transport, EventMask(Event.none), EventMask(Event.read, Event.write));
+            connection.incoming.enqueue(transport);
+        }
+
+        if (!connection.incoming.empty)
+        {
+            pendings.enqueue(connection);
+        }
+    }
+}

source/tanya/async/iocp.d

@@ -0,0 +1,55 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module provides API for Windows I/O Completion Ports.
+ *
+ * Note: Available only on Windows.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.iocp;
+
+version (Windows)
+{
+    version = WindowsDoc;
+}
+else version (D_Ddoc)
+{
+    version = WindowsDoc;
+    version (Windows)
+    {
+    }
+    else
+    {
+        private struct OVERLAPPED
+        {
+        }
+        private alias HANDLE = void*;
+    }
+}
+
+version (WindowsDoc):
+
+import core.sys.windows.winbase;
+import core.sys.windows.windef;
+
+/**
+ * Provides an extendable representation of a Win32 $(D_PSYMBOL OVERLAPPED)
+ * structure.
+ */
+class State
+{
+    /// For internal use by Windows API.
+    align(1) OVERLAPPED overlapped;
+
+    /// File/socket handle.
+    HANDLE handle;
+
+    /// For keeping events or event masks.
+    int event;
+}

source/tanya/async/loop.d

@@ -0,0 +1,433 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Interface for the event loop implementations and the default event loop
+ * chooser.
+ *
+ * ---
+ * import tanya.async;
+ * import tanya.memory;
+ * import tanya.network.socket;
+ *
+ * class EchoProtocol : TransmissionControlProtocol
+ * {
+ *  private DuplexTransport transport;
+ *
+ *  void received(in ubyte[] data) @nogc
+ *  {
+ *      transport.write(data);
+ *  }
+ *
+ *  void connected(DuplexTransport transport) @nogc
+ *  {
+ *      this.transport = transport;
+ *  }
+ *
+ *  void disconnected(SocketException e) @nogc
+ *  {
+ *  }
+ * }
+ *
+ * void main()
+ * {
+ *  auto address = defaultAllocator.make!InternetAddress("127.0.0.1", cast(ushort) 8192);
+ *
+ *  version (Windows)
+ *  {
+ *      auto sock = defaultAllocator.make!OverlappedStreamSocket(AddressFamily.inet);
+ *  }
+ *  else
+ *  {
+ *      auto sock = defaultAllocator.make!StreamSocket(AddressFamily.inet);
+ *      sock.blocking = false;
+ *  }
+ *
+ *  sock.bind(address);
+ *  sock.listen(5);
+ *
+ *  auto io = defaultAllocator.make!ConnectionWatcher(sock);
+ *  io.setProtocol!EchoProtocol;
+ *
+ *  defaultLoop.start(io);
+ *  defaultLoop.run();
+ *
+ *  sock.shutdown();
+ *  defaultAllocator.dispose(io);
+ *  defaultAllocator.dispose(sock);
+ *  defaultAllocator.dispose(address);
+ * }
+ * ---
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.loop;
+
+import core.time;
+import std.algorithm.iteration;
+import std.algorithm.mutation;
+import std.typecons;
+import tanya.async.transport;
+import tanya.async.watcher;
+import tanya.container.buffer;
+import tanya.container.queue;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+
+version (DisableBackends)
+{
+}
+else version (D_Ddoc)
+{
+}
+else version (linux)
+{
+    import tanya.async.event.epoll;
+    version = Epoll;
+}
+else version (Windows)
+{
+    import tanya.async.event.iocp;
+    version = IOCP;
+}
+else version (OSX)
+{
+    version = Kqueue;
+}
+else version (iOS)
+{
+    version = Kqueue;
+}
+else version (FreeBSD)
+{
+    version = Kqueue;
+}
+else version (OpenBSD)
+{
+    version = Kqueue;
+}
+else version (DragonFlyBSD)
+{
+    version = Kqueue;
+}
+version (unittest)
+{
+    final class TestLoop : Loop
+    {
+        override protected bool reify(SocketWatcher watcher,
+                                      EventMask oldEvents,
+                                      EventMask events) @nogc
+        {
+            return true;
+        }
+
+        override protected void poll() @nogc
+        {
+            assert(!this.done);
+            unloop();
+        }
+
+        override protected @property uint maxEvents()
+        const pure nothrow @safe @nogc
+        {
+            return 64U;
+        }
+    }
+}
+
+/**
+ * Events.
+ */
+enum Event : uint
+{
+    none   = 0x00,       /// No events.
+    read   = 0x01,       /// Non-blocking read call.
+    write  = 0x02,       /// Non-blocking write call.
+    accept = 0x04,       /// Connection made.
+    error  = 0x80000000, /// Sent when an error occurs.
+}
+
+alias EventMask = BitFlags!Event;
+
+/**
+ * Event loop.
+ */
+abstract class Loop
+{
+    private bool done = true;
+
+    /// Pending watchers.
+    protected Queue!Watcher pendings;
+
+    /**
+     * Returns: Maximal event count can be got at a time
+     *          (should be supported by the backend).
+     */
+    protected @property uint maxEvents()
+    const pure nothrow @safe @nogc
+    {
+        return 128U;
+    }
+
+    private unittest
+    {
+        auto loop = defaultAllocator.make!TestLoop;
+        assert(loop.maxEvents == 64);
+
+        defaultAllocator.dispose(loop);
+    }
+
+    /**
+     * Initializes the loop.
+     */
+    this() @nogc
+    {
+        pendings = Queue!Watcher(MmapPool.instance);
+    }
+
+    /**
+     * Frees loop internals.
+     */
+    ~this() @nogc
+    {
+        foreach (w; pendings)
+        {
+            MmapPool.instance.dispose(w);
+        }
+    }
+
+    /**
+     * Starts the loop.
+     */
+    void run() @nogc
+    {
+        this.done = false;
+        do
+        {
+            poll();
+
+            // Invoke pendings
+            foreach (ref w; this.pendings)
+            {
+                w.invoke();
+            }
+        }
+        while (!this.done);
+    }
+
+    /**
+     * Break out of the loop.
+     */
+    void unloop() @safe pure nothrow @nogc
+    {
+        this.done = true;
+    }
+
+    private unittest
+    {
+        auto loop = defaultAllocator.make!TestLoop;
+        assert(loop.done);
+
+        loop.run();
+        assert(loop.done);
+
+        defaultAllocator.dispose(loop);
+    }
+
+    private unittest
+    {
+        auto loop = defaultAllocator.make!TestLoop;
+        auto watcher = defaultAllocator.make!DummyWatcher;
+        loop.pendings.enqueue(watcher);
+
+        assert(!watcher.invoked);
+        loop.run();
+        assert(watcher.invoked);
+
+        defaultAllocator.dispose(loop);
+        defaultAllocator.dispose(watcher);
+    }
+
+    /**
+     * Start watching.
+     *
+     * Params:
+     *  watcher = Watcher.
+     */
+    void start(ConnectionWatcher watcher) @nogc
+    {
+        if (watcher.active)
+        {
+            return;
+        }
+        watcher.active = true;
+
+        reify(watcher, EventMask(Event.none), EventMask(Event.accept));
+    }
+
+    /**
+     * Stop watching.
+     *
+     * Params:
+     *  watcher = Watcher.
+     */
+    void stop(ConnectionWatcher watcher) @nogc
+    {
+        if (!watcher.active)
+        {
+            return;
+        }
+        watcher.active = false;
+
+        reify(watcher, EventMask(Event.accept), EventMask(Event.none));
+    }
+
+    /**
+     * Should be called if the backend configuration changes.
+     *
+     * Params:
+     *  watcher   = Watcher.
+     *  oldEvents = The events were already set.
+     *  events    = The events should be set.
+     *
+     * Returns: $(D_KEYWORD true) if the operation was successful.
+     */
+    abstract protected bool reify(SocketWatcher watcher,
+                                  EventMask oldEvents,
+                                  EventMask events) @nogc;
+
+    /**
+     * Returns: The blocking time.
+     */
+    protected @property inout(Duration) blockTime()
+    inout @safe pure nothrow @nogc
+    {
+        // Don't block if we have to do.
+        return pendings.empty ? blockTime_ : Duration.zero;
+    }
+
+    /**
+     * Sets the blocking time for IO watchers.
+     *
+     * Params:
+     *  blockTime = The blocking time. Cannot be larger than
+     *              $(D_PSYMBOL maxBlockTime).
+     */
+    protected @property void blockTime(in Duration blockTime) @safe pure nothrow @nogc
+    in
+    {
+        assert(blockTime <= 1.dur!"hours", "Too long to wait.");
+        assert(!blockTime.isNegative);
+    }
+    body
+    {
+        blockTime_ = blockTime;
+    }
+
+    private unittest
+    {
+        auto loop = defaultAllocator.make!TestLoop;
+        assert(loop.blockTime == 1.dur!"minutes");
+
+        loop.blockTime = 2.dur!"minutes";
+        assert(loop.blockTime == 2.dur!"minutes");
+
+        defaultAllocator.dispose(loop);
+    }
+
+    /**
+     * Does the actual polling.
+     */
+    abstract protected void poll() @nogc;
+
+    /// Maximal block time.
+    protected Duration blockTime_ = 1.dur!"minutes";
+}
+
+/**
+ * Exception thrown on errors in the event loop.
+ */
+class BadLoopException : Exception
+{
+    /**
+     * Params:
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string file = __FILE__, size_t line = __LINE__, Throwable next = null)
+    pure nothrow const @safe @nogc
+    {
+        super("Event loop cannot be initialized.", file, line, next);
+    }
+}
+
+/**
+ * Returns the event loop used by default. If an event loop wasn't set with
+ * $(D_PSYMBOL defaultLoop) before, $(D_PSYMBOL defaultLoop) will try to
+ * choose an event loop supported on the system.
+ *
+ * Returns: The default event loop.
+ */
+@property Loop defaultLoop() @nogc
+{
+    if (defaultLoop_ !is null)
+    {
+        return defaultLoop_;
+    }
+    version (Epoll)
+    {
+        defaultLoop_ = MmapPool.instance.make!EpollLoop;
+    }
+    else version (IOCP)
+    {
+        defaultLoop_ = MmapPool.instance.make!IOCPLoop;
+    }
+    else version (Kqueue)
+    {
+        import tanya.async.event.kqueue;
+        defaultLoop_ = MmapPool.instance.make!KqueueLoop;
+    }
+    return defaultLoop_;
+}
+
+/**
+ * Sets the default event loop.
+ *
+ * This property makes it possible to implement your own backends or event
+ * loops, for example, if the system is not supported or if you want to
+ * extend the supported implementation. Just extend $(D_PSYMBOL Loop) and pass
+ * your implementation to this property.
+ *
+ * Params:
+ *  loop = The event loop.
+ */
+@property void defaultLoop(Loop loop) @nogc
+in
+{
+    assert(loop !is null);
+}
+body
+{
+    defaultLoop_ = loop;
+}
+
+private Loop defaultLoop_;
+
+private unittest
+{
+    auto oldLoop = defaultLoop_;
+    auto loop = defaultAllocator.make!TestLoop;
+
+    defaultLoop = loop;
+    assert(defaultLoop_ is loop);
+    assert(defaultLoop is loop);
+
+    defaultLoop_ = oldLoop;
+    defaultAllocator.dispose(loop);
+}

source/tanya/async/package.d

@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This package provides asynchronous capabilities.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async;
+
+public import tanya.async.loop;
+public import tanya.async.protocol;
+public import tanya.async.transport;
+public import tanya.async.watcher;

source/tanya/async/protocol.d

@@ -0,0 +1,56 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module contains protocol which handle data in asynchronous
+ * applications.
+ *
+ * When an event from the network arrives, a protocol method gets
+ * called and can respond to the event.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.protocol;
+
+import tanya.network.socket;
+import tanya.async.transport;
+
+/**
+ * Common protocol interface.
+ */
+interface Protocol
+{
+    /**
+     * Params:
+     *  data = Read data.
+     */
+    void received(in ubyte[] data) @nogc;
+
+    /**
+     * Called when a connection is made.
+     *
+     * Params:
+     *  transport = Protocol transport.
+     */
+    void connected(DuplexTransport transport) @nogc;
+
+    /**
+     * Called when a connection is lost.
+     *
+     * Params:
+     *  exception = $(D_PSYMBOL Exception) if an error caused
+     *              the disconnect, $(D_KEYWORD null) otherwise.
+     */
+    void disconnected(SocketException exception) @nogc;
+}
+
+/**
+ * Interface for TCP.
+ */
+interface TransmissionControlProtocol  : Protocol
+{
+}

source/tanya/async/transport.d

@@ -0,0 +1,103 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module contains transports which are responsible for data dilvery
+ * between two parties of an asynchronous communication.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.transport;
+
+import tanya.async.protocol;
+import tanya.network.socket;
+
+/**
+ * Base transport interface.
+ */
+interface Transport
+{
+}
+
+/**
+ * Interface for read-only transports.
+ */
+interface ReadTransport : Transport
+{
+}
+
+/**
+ * Interface for write-only transports.
+ */
+interface WriteTransport : Transport
+{
+    /**
+     * Write some data to the transport.
+     *
+     * Params:
+     *  data = Data to send.
+     */
+    void write(ubyte[] data) @nogc;
+}
+
+/**
+ * Represents a bidirectional transport.
+ */
+interface DuplexTransport : ReadTransport, WriteTransport
+{
+    /**
+     * Returns: Application protocol.
+     *
+     * Postcondition: $(D_INLINECODE protocol !is null)
+     */
+    @property Protocol protocol() pure nothrow @safe @nogc
+    out (protocol)
+    {
+        assert(protocol !is null);
+    }
+
+    /**
+     * Switches the protocol.
+     *
+     * The protocol is deallocated by the event loop, it should currently be
+     * allocated with $(D_PSYMBOL MmapPool).
+     *
+     * Params:
+     *  protocol = Application protocol.
+     *
+     * Precondition: $(D_INLINECODE protocol !is null)
+     */
+    @property void protocol(Protocol protocol) pure nothrow @safe @nogc
+    in
+    {
+        assert(protocol !is null);
+    }
+
+
+    /**
+     * Returns $(D_PARAM true) if the transport is closing or closed.
+     */
+    bool isClosing() const pure nothrow @safe @nogc;
+
+    /**
+     * Close the transport.
+     *
+     * Buffered data will be flushed.  No more data will be received.
+     */
+    void close() @nogc;
+}
+
+/**
+ * Represents a socket transport.
+ */
+interface SocketTransport : Transport
+{
+    /**
+     * Returns: Socket.
+     */
+    @property Socket socket() pure nothrow @safe @nogc;
+}

source/tanya/async/watcher.d

@@ -0,0 +1,132 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Watchers register user's interest in some event.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.async.watcher;
+
+import std.functional;
+import std.exception;
+import tanya.async.loop;
+import tanya.async.protocol;
+import tanya.async.transport;
+import tanya.container.buffer;
+import tanya.container.queue;
+import tanya.memory;
+import tanya.memory.mmappool;
+import tanya.network.socket;
+
+/**
+ * A watcher is an opaque structure that you allocate and register to record
+ * your interest in some event. 
+ */
+abstract class Watcher
+{
+    /// Whether the watcher is active.
+    bool active;
+
+    /**
+     * Invoke some action on event.
+     */
+    void invoke() @nogc;
+}
+
+version (unittest)
+{
+    final class DummyWatcher : Watcher
+    {
+        bool invoked;
+
+        override void invoke() @nogc
+        {
+            this.invoked = true;
+        }
+    }
+}
+
+/**
+ * Socket watcher.
+ */
+abstract class SocketWatcher : Watcher
+{
+    /// Watched socket.
+    protected Socket socket_;
+
+    /**
+     * Params:
+     *  socket = Socket.
+     *
+     * Precondition: $(D_INLINECODE socket !is null)
+     */
+    this(Socket socket) pure nothrow @safe @nogc
+    in
+    {
+        assert(socket !is null);
+    }
+    body
+    {
+        socket_ = socket;
+    }
+
+    /**
+     * Returns: Socket.
+     */
+    @property Socket socket() pure nothrow @safe @nogc
+    {
+        return socket_;
+    }
+}
+
+/**
+ * Connection watcher.
+ */
+class ConnectionWatcher : SocketWatcher
+{
+    /// Incoming connection queue.
+    Queue!DuplexTransport incoming;
+
+    private Protocol delegate() @nogc protocolFactory;
+
+    /**
+     * Params:
+     *  socket = Socket.
+     */
+    this(Socket socket) @nogc
+    {
+        super(socket);
+        incoming = Queue!DuplexTransport(MmapPool.instance);
+    }
+
+    /**
+     * Params:
+     *  P = Protocol should be used.
+     */
+    void setProtocol(P : Protocol)() @nogc
+    {
+        this.protocolFactory = () @nogc => cast(Protocol) MmapPool.instance.make!P;
+    }
+
+    /**
+     * Invokes new connection callback.
+     */
+    override void invoke() @nogc
+    in
+    {
+        assert(protocolFactory !is null, "Protocol isn't set.");
+    }
+    body
+    {
+        foreach (transport; incoming)
+        {
+            transport.protocol = protocolFactory();
+            transport.protocol.connected(transport);
+        }
+    }
+}

source/tanya/container/buffer.d

@@ -3,361 +3,385 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * This module contains buffers designed for C-style input/output APIs.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
 module tanya.container.buffer;
 
+import std.traits;
 import tanya.memory;
 
-@nogc:
-
 version (unittest)
 {
-	private int fillBuffer(void* buffer,
+    private int fillBuffer(ubyte[] buffer,
                            in size_t size,
                            int start = 0,
-	                       int end = 10)
+                           int end = 10) @nogc pure nothrow
     in
     {
         assert(start < end);
     }
     body
     {
-		ubyte[] buf = cast(ubyte[]) buffer[0..size];
         auto numberRead = end - start;
-
         for (ubyte i; i < numberRead; ++i)
         {
-			buf[i] = cast(ubyte) (start + i);
+            buffer[i] = cast(ubyte) (start + i);
         }
         return numberRead;
     }
 }
 
 /**
- * Interface for implemeting input/output buffers.
+ * Self-expanding buffer, that can be used with functions returning the number
- */
+ * of the read bytes.
-interface Buffer
+ *
-{
+ * This buffer supports asynchronous reading. It means you can pass a new chunk
-@nogc:
+ * to an asynchronous read function during you are working with already
-	/**
+ * available data. But only one asynchronous call at a time is supported. Be
-	 * Returns: The size of the internal buffer.
+ * sure to call $(D_PSYMBOL ReadBuffer.clear()) before you append the result
-	 */
+ * of the pended asynchronous call.
-	@property size_t capacity() const @safe pure nothrow;
-
-	/**
-	 * Returns: Data size.
-	 */
-	@property size_t length() const @safe pure nothrow;
-
-	/**
-	 * Returns: Available space.
-	 */
-	@property size_t free() const @safe pure nothrow;
-
-	/**
-	 * Appends some data to the buffer.
  *
  * Params:
-	 * 	buffer = Buffer chunk got with $(D_PSYMBOL buffer).
+ *  T = Buffer type.
  */
-	Buffer opOpAssign(string op)(void[] buffer)
+struct ReadBuffer(T = ubyte)
-		if (op == "~");
+    if (isScalarType!T)
-}
-
-/**
- * Buffer that can be used with C functions accepting void pointer and
- * returning the number of the read bytes.
- */
-class ReadBuffer : Buffer
 {
-@nogc:
     /// Internal buffer.
-	protected ubyte[] _buffer;
+    private T[] buffer_;
 
     /// Filled buffer length.
-	protected size_t _length;
+    private size_t length_;
+
+    /// Start of available data.
+    private size_t start;
+
+    /// Last position returned with $(D_KEYWORD []).
+    private size_t ring;
 
     /// Available space.
-	protected immutable size_t minAvailable;
+    private immutable size_t minAvailable = 1024;
 
     /// Size by which the buffer will grow.
-	protected immutable size_t blockSize;
+    private immutable size_t blockSize = 8192;
-
-	private Allocator allocator;
 
     invariant
     {
-		assert(_length <= _buffer.length);
+        assert(length_ <= buffer_.length);
         assert(blockSize > 0);
         assert(minAvailable > 0);
     }
 
     /**
+     * Creates a new read buffer.
+     *
      * Params:
      *  size         = Initial buffer size and the size by which the buffer
      *                 will grow.
      *  minAvailable = minimal size should be always  available to fill.
      *                 So it will reallocate if $(D_INLINECODE
-	 * 	               $(D_PSYMBOL free) < $(D_PARAM minAvailable)
+     *                 $(D_PSYMBOL free) < $(D_PARAM minAvailable)).
-	 * 	               ).
+     *  allocator    = Allocator.
      */
-	this(size_t size = 8192,
+    this(in size_t size,
-	     size_t minAvailable = 1024,
+         in size_t minAvailable = 1024,
-	     Allocator allocator = defaultAllocator)
+         shared Allocator allocator = defaultAllocator) @trusted
     {
-		this.allocator = allocator;
+        this(allocator);
         this.minAvailable = minAvailable;
         this.blockSize = size;
-		resizeArray!ubyte(this.allocator, _buffer, size);
+        buffer_ = cast(T[]) allocator_.allocate(size * T.sizeof);
+    }
+
+    /// Ditto.
+    this(shared Allocator allocator)
+    in
+    {
+        assert(allocator_ is null);
+    }
+    body
+    {
+        allocator_ = allocator;
     }
 
     /**
      * Deallocates the internal buffer.
      */
-	~this()
+    ~this() @trusted
     {
-		finalize(allocator, _buffer);
+        allocator.deallocate(buffer_);
     }
 
     ///
     unittest
     {
-		auto b = make!ReadBuffer(defaultAllocator);
+        ReadBuffer!ubyte b;
-		assert(b.capacity == 8192);
+        assert(b.capacity == 0);
         assert(b.length == 0);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
      * Returns: The size of the internal buffer.
      */
-	@property size_t capacity() const @safe pure nothrow
+    @property size_t capacity() const
     {
-		return _buffer.length;
+        return buffer_.length;
     }
 
     /**
      * Returns: Data size.
      */
-	@property size_t length() const @safe pure nothrow
+    @property size_t length() const
     {
-		return _length;
+        return length_ - start;
+    }
+
+    /// Ditto.
+    alias opDollar = length;
+
+    /**
+     * Clears the buffer.
+     *
+     * Returns: $(D_KEYWORD this).
+     */
+    void clear()
+    {
+        start = length_ = ring;
     }
 
     /**
      * Returns: Available space.
      */
-	@property size_t free() const @safe pure nothrow
+    @property size_t free() const
     {
-		return capacity - length;
+        return length > ring ? capacity - length : capacity - ring;
     }
 
     ///
     unittest
     {
-		auto b = make!ReadBuffer(defaultAllocator);
+        ReadBuffer!ubyte b;
         size_t numberRead;
-		void* buf;
+
+        assert(b.free == 0);
 
         // Fills the buffer with values 0..10
-		assert(b.free == b.blockSize);
+        numberRead = fillBuffer(b[], b.free, 0, 10);
-		buf =  b.buffer;
+        b += numberRead;
-		numberRead = fillBuffer(buf, b.free, 0, 10);
-		b ~= buf[0..numberRead];
         assert(b.free == b.blockSize - numberRead);
-		b[];
+        b.clear();
         assert(b.free == b.blockSize);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
-	 * Returns a pointer to a chunk of the internal buffer. You can pass it to
+     * Appends some data to the buffer.
-	 * a function that requires such a buffer.
-	 *
-	 * Set the buffer again after reading something into it. Append
-	 * $(D_KEYWORD ~=) a slice from the beginning of the buffer you got and
-	 * till the number of the read bytes. The data will be appended to the
-	 * existing buffer.
-	 *
-	 * Returns: A chunk of available buffer.
-	 */
-	@property void* buffer()
-	{
-		if (capacity - length < minAvailable)
-		{
-			resizeArray!ubyte(this.allocator, _buffer, capacity + blockSize);
-		}
-		return _buffer[_length..$].ptr;
-	}
-
-	/**
-	 * Appends some data to the buffer. Use only the buffer you got
-	 * with $(D_PSYMBOL buffer)!
      *
      * Params:
-	 * 	buffer = Buffer chunk got with $(D_PSYMBOL buffer).
+     *  length = Number of the bytes read.
+     *
+     * Returns: $(D_KEYWORD this).
      */
-	ReadBuffer opOpAssign(string op)(void[] buffer)
+    ref ReadBuffer opOpAssign(string op)(in size_t length)
-		if (op == "~")
+        if (op == "+")
     {
-		_length += buffer.length;
+        length_ += length;
+        ring = start;
         return this;
     }
 
     ///
     unittest
     {
-		auto b = make!ReadBuffer(defaultAllocator);
+        ReadBuffer!ubyte b;
         size_t numberRead;
-		void* buf;
         ubyte[] result;
 
         // Fills the buffer with values 0..10
-		buf =  b.buffer;
+        numberRead = fillBuffer(b[], b.free, 0, 10);
-		numberRead = fillBuffer(buf, b.free, 0, 10);
+        b += numberRead;
-		b ~= buf[0..numberRead];
 
-		result = b[];
+        result = b[0 .. $];
         assert(result[0] == 0);
         assert(result[1] == 1);
         assert(result[9] == 9);
+        b.clear();
 
         // It shouldn't overwrite, but append another 5 bytes to the buffer
-		buf =  b.buffer;
+        numberRead = fillBuffer(b[], b.free, 0, 10);
-		numberRead = fillBuffer(buf, b.free, 0, 10);
+        b += numberRead;
-		b ~= buf[0..numberRead];
 
-		buf =  b.buffer;
+        numberRead = fillBuffer(b[], b.free, 20, 25);
-		numberRead = fillBuffer(buf, b.free, 20, 25);
+        b += numberRead;
-		b ~= buf[0..numberRead];
 
-		result = b[];
+        result = b[0..$];
         assert(result[0] == 0);
         assert(result[1] == 1);
         assert(result[9] == 9);
         assert(result[10] == 20);
         assert(result[14] == 24);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
-	 * Returns the buffer. The buffer is cleared after that. So you can get it
+     * Params:
-	 * only one time.
+     *  start = Start position.
+     *  end   = End position.
      *
-	 * Returns: The buffer as array.
+     * Returns: Array between $(D_PARAM start) and $(D_PARAM end).
      */
-	@property ubyte[] opIndex()
+    T[] opSlice(in size_t start, in size_t end)
     {
-		auto ret = _buffer[0.._length];
+        return buffer_[this.start + start .. this.start + end];
-		_length = 0;
+    }
+
+    /**
+     * Returns a free chunk of the buffer.
+     *
+     * Add ($(D_KEYWORD +=)) the number of the read bytes after using it.
+     *
+     * Returns: A free chunk of the buffer.
+     */
+    T[] opIndex()
+    {
+        if (start > 0)
+        {
+            auto ret = buffer_[0 .. start];
+            ring = 0;
             return ret;
         }
+        else
+        {
+            if (capacity - length < minAvailable)
+            {
+                void[] buf = buffer_;
+                immutable cap = capacity;
+                () @trusted {
+                    allocator.reallocate(buf, (cap + blockSize) * T.sizeof);
+                    buffer_ = cast(T[]) buf;
+                }();
+            }
+            ring = length_;
+            return buffer_[length_ .. $];
+        }
+    }
 
     ///
     unittest
     {
-		auto b = make!ReadBuffer(defaultAllocator);
+        ReadBuffer!ubyte b;
         size_t numberRead;
-		void* buf;
         ubyte[] result;
 
         // Fills the buffer with values 0..10
-		buf =  b.buffer;
+        numberRead = fillBuffer(b[], b.free, 0, 10);
-		numberRead = fillBuffer(buf, b.free, 0, 10);
+        b += numberRead;
-		b ~= buf[0..numberRead];
 
         assert(b.length == 10);
-		result = b[];
+        result = b[0 .. $];
         assert(result[0] == 0);
         assert(result[9] == 9);
+        b.clear();
         assert(b.length == 0);
-
-		finalize(defaultAllocator, b);
     }
+
+    mixin DefaultAllocator;
+}
+
+private unittest
+{
+    static assert(is(ReadBuffer!int));
 }
 
 /**
- * Circular, self-expanding buffer that can be used with C functions accepting
+ * Circular, self-expanding buffer with overflow support. Can be used with
- * void pointer and returning the number of the read bytes.
+ * functions returning the number of the transferred bytes.
  *
  * The buffer is optimized for situations where you read all the data from it
  * at once (without writing to it occasionally). It can become ineffective if
  * you permanently keep some data in the buffer and alternate writing and
  * reading, because it may allocate and move elements.
+ *
+ * Params:
+ *  T = Buffer type.
  */
-class WriteBuffer : Buffer
+struct WriteBuffer(T = ubyte)
+    if (isScalarType!T)
 {
-@nogc:
     /// Internal buffer.
-	protected ubyte[] _buffer;
+    private T[] buffer_;
 
     /// Buffer start position.
-	protected size_t start;
+    private size_t start;
 
     /// Buffer ring area size. After this position begins buffer overflow area.
-	protected size_t ring;
+    private size_t ring;
 
     /// Size by which the buffer will grow.
-	protected immutable size_t blockSize;
+    private immutable size_t blockSize;
 
     /// The position of the free area in the buffer.
-	protected size_t position;
+    private size_t position;
-
-	private Allocator allocator;
 
     invariant
     {
         assert(blockSize > 0);
-		// position can refer to an element outside the buffer if the buffer is full.
+        // Position can refer to an element outside the buffer if the buffer is full.
-		assert(position <= _buffer.length);
+        assert(position <= buffer_.length);
     }
 
     /**
      * Params:
-	 *  size = Initial buffer size and the size by which the buffer
+     *  size      = Initial buffer size and the size by which the buffer will
-	 * 	       will grow.
+     *              grow.
+     *  allocator = Allocator.
+     *
+     * Precondition: $(D_INLINECODE size > 0 && allocator !is null)
      */
-	this(size_t size = 8192,
+    this(in size_t size, shared Allocator allocator = defaultAllocator) @trusted
-	     Allocator allocator = defaultAllocator)
+    in
+    {
+        assert(size > 0);
+        assert(allocator !is null);
+    }
+    body
     {
-		this.allocator = allocator;
         blockSize = size;
         ring = size - 1;
-		resizeArray!ubyte(this.allocator, _buffer, size);
+        allocator_ = allocator;
+        buffer_ = cast(T[]) allocator_.allocate(size * T.sizeof);
     }
 
+    @disable this();
+
     /**
      * Deallocates the internal buffer.
      */
     ~this()
     {
-		finalize(allocator, _buffer);
+        allocator.deallocate(buffer_);
     }
 
     /**
      * Returns: The size of the internal buffer.
      */
-	@property size_t capacity() const @safe pure nothrow
+    @property size_t capacity() const
     {
-		return _buffer.length;
+        return buffer_.length;
     }
 
     /**
      * Note that $(D_PSYMBOL length) doesn't return the real length of the data,
-	 * but only the array length that will be returned with $(D_PSYMBOL buffer)
+     * but only the array length that will be returned with $(D_PSYMBOL opIndex)
-	 * next time. Be sure to call $(D_PSYMBOL buffer) and set $(D_PSYMBOL written)
+     * next time. Be sure to call $(D_PSYMBOL opIndex) and set $(D_KEYWORD +=)
      * until $(D_PSYMBOL length) returns 0.
      *
      * Returns: Data size.
      */
-	@property size_t length() const @safe pure nothrow
+    @property size_t length() const
     {
         if (position > ring || position < start) // Buffer overflowed
         {
@@ -369,34 +393,35 @@ class WriteBuffer : Buffer
         }
     }
 
+    /// Ditto.
+    alias opDollar = length;
+
     ///
     unittest
     {
-		auto b = make!WriteBuffer(defaultAllocator, 4);
+        auto b = WriteBuffer!ubyte(4);
         ubyte[3] buf = [48, 23, 255];
 
         b ~= buf;
         assert(b.length == 3);
-		b.written = 2;
+        b += 2;
         assert(b.length == 1);
 
         b ~= buf;
         assert(b.length == 2);
-		b.written = 2;
+        b += 2;
         assert(b.length == 2);
 
         b ~= buf;
         assert(b.length == 5);
-		b.written = b.length;
+        b += b.length;
         assert(b.length == 0);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
      * Returns: Available space.
      */
-	@property size_t free() const @safe pure nothrow
+    @property size_t free() const
     {
         return capacity - length;
     }
@@ -405,9 +430,9 @@ class WriteBuffer : Buffer
      * Appends data to the buffer.
      *
      * Params:
-	 * 	buffer = Buffer chunk got with $(D_PSYMBOL buffer).
+     *  buffer = Buffer chunk got with $(D_PSYMBOL opIndex).
      */
-	WriteBuffer opOpAssign(string op)(ubyte[] buffer)
+    ref WriteBuffer opOpAssign(string op)(in T[] buffer)
         if (op == "~")
     {
         size_t end, start;
@@ -422,7 +447,7 @@ class WriteBuffer : Buffer
                 end = afterRing;
             }
             start = end - position;
-			_buffer[position..end] = buffer[0..start];
+            buffer_[position .. end] = buffer[0 .. start];
             if (end == afterRing)
             {
                 position = this.start == 0 ? afterRing : 0;
@@ -442,7 +467,7 @@ class WriteBuffer : Buffer
                 end = this.start;
             }
             auto areaEnd = end - position + start;
-			_buffer[position..end] = buffer[start..areaEnd];
+            buffer_[position .. end] = buffer[start .. areaEnd];
             position = end == this.start ? ring + 1 : end - position;
             start = areaEnd;
         }
@@ -453,11 +478,14 @@ class WriteBuffer : Buffer
             end = position + buffer.length - start;
             if (end > capacity)
             {
-				auto newSize = end / blockSize * blockSize + blockSize;
+                auto newSize = (end / blockSize * blockSize + blockSize) * T.sizeof;
-
+                () @trusted {
-				resizeArray!ubyte(this.allocator, _buffer, newSize);
+                    void[] buf = buffer_;
+                    allocator.reallocate(buf, newSize);
+                    buffer_ = cast(T[]) buf;
+                }();
             }
-			_buffer[position..end] = buffer[start..$];
+            buffer_[position .. end] = buffer[start .. $];
             position = end;
             if (this.start == 0)
             {
@@ -471,47 +499,50 @@ class WriteBuffer : Buffer
     ///
     unittest
     {
-		auto b = make!WriteBuffer(defaultAllocator, 4);
+        auto b = WriteBuffer!ubyte(4);
         ubyte[3] buf = [48, 23, 255];
 
         b ~= buf;
         assert(b.capacity == 4);
-		assert(b._buffer[0] == 48 && b._buffer[1] == 23 && b._buffer[2] == 255);
+        assert(b.buffer_[0] == 48 && b.buffer_[1] == 23 && b.buffer_[2] == 255);
 
-		b.written = 2;
+        b += 2;
         b ~= buf;
         assert(b.capacity == 4);
-		assert(b._buffer[0] == 23 && b._buffer[1] == 255
+        assert(b.buffer_[0] == 23 && b.buffer_[1] == 255
-		    && b._buffer[2] == 255 && b._buffer[3] == 48);
+            && b.buffer_[2] == 255 && b.buffer_[3] == 48);
 
-		b.written = 2;
+        b += 2;
         b ~= buf;
         assert(b.capacity == 8);
-		assert(b._buffer[0] == 23 && b._buffer[1] == 255
+        assert(b.buffer_[0] == 23 && b.buffer_[1] == 255
-		    && b._buffer[2] == 48 && b._buffer[3] == 23 && b._buffer[4] == 255);
+            && b.buffer_[2] == 48 && b.buffer_[3] == 23 && b.buffer_[4] == 255);
+    }
 
-		finalize(defaultAllocator, b);
+    ///
-
+    unittest
-		b = make!WriteBuffer(defaultAllocator, 2);
+    {
+        auto b = WriteBuffer!ubyte(2);
+        ubyte[3] buf = [48, 23, 255];
 
         b ~= buf;
         assert(b.start == 0);
         assert(b.capacity == 4);
         assert(b.ring == 3);
         assert(b.position == 3);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
      * Sets how many bytes were written. It will shrink the buffer
-	 * appropriately. Always set this property after calling
+     * appropriately. Always call it after $(D_PSYMBOL opIndex).
-	 * $(D_PSYMBOL buffer).
      *
      * Params:
      *  length = Length of the written data.
+     *
+     * Returns: $(D_KEYWORD this).
      */
-	@property void written(size_t length) @safe pure nothrow
+    ref WriteBuffer opOpAssign(string op)(in size_t length)
+        if (op == "+")
     in
     {
         assert(length <= this.length);
@@ -523,7 +554,7 @@ class WriteBuffer : Buffer
 
         if (length <= 0)
         {
-			return;
+            return this;
         }
         else if (position <= afterRing)
         {
@@ -537,19 +568,21 @@ class WriteBuffer : Buffer
         {
             auto overflow = position - afterRing;
 
-            if (overflow > length) {
+            if (overflow > length)
-                _buffer[start.. start + length] = _buffer[afterRing.. afterRing + length];
+            {
-                _buffer[afterRing.. afterRing + length] = _buffer[afterRing + length ..position];
+                immutable afterLength = afterRing + length;
+                buffer_[start .. start + length] = buffer_[afterRing .. afterLength];
+                buffer_[afterRing .. afterLength] = buffer_[afterLength .. position];
                 position -= length;
             }
             else if (overflow == length)
             {
-                _buffer[start.. start + overflow] = _buffer[afterRing..position];
+                buffer_[start .. start + overflow] = buffer_[afterRing .. position];
                 position -= overflow;
             }
             else
             {
-                _buffer[start.. start + overflow] = _buffer[afterRing..position];
+                buffer_[start .. start + overflow] = buffer_[afterRing .. position];
                 position = overflow;
             }
             start += length;
@@ -568,74 +601,90 @@ class WriteBuffer : Buffer
         {
             start = 0;
         }
+        return this;
     }
 
     ///
     unittest
     {
-		auto b = make!WriteBuffer(defaultAllocator);
+        auto b = WriteBuffer!ubyte(6);
         ubyte[6] buf = [23, 23, 255, 128, 127, 9];
 
         b ~= buf;
         assert(b.length == 6);
-		b.written = 2;
+        b += 2;
         assert(b.length == 4);
-		b.written = 4;
+        b += 4;
         assert(b.length == 0);
-
-		finalize(defaultAllocator, b);
     }
 
     /**
-	 * Returns a pointer to a buffer chunk with data. You can pass it to
+     * Returns a chunk with data.
-	 * a function that requires such a buffer.
      *
-	 * After calling it, set $(D_PSYMBOL written) to the length could be
+     * After calling it, set $(D_KEYWORD +=) to the length could be
      * written.
      *
-	 * $(D_PSYMBOL buffer) may return only part of the data. You may need
+     * $(D_PSYMBOL opIndex) may return only part of the data. You may need
-	 * to call it (and set $(D_PSYMBOL written) several times until
+     * to call it and set $(D_KEYWORD +=) several times until
      * $(D_PSYMBOL length) is 0. If all the data can be written,
      * maximally 3 calls are required.
      *
      * Returns: A chunk of data buffer.
      */
-	@property void* buffer() @safe pure nothrow
+    T[] opSlice(in size_t start, in size_t end)
     {
+        immutable internStart = this.start + start;
+
         if (position > ring || position < start) // Buffer overflowed
         {
-			return _buffer[start.. ring + 1].ptr;
+            return buffer_[this.start .. ring + 1 - length + end];
         }
         else
         {
-			return _buffer[start..position].ptr;
+            return buffer_[this.start .. this.start + end];
         }
     }
 
     ///
     unittest
     {
-		auto b = make!WriteBuffer(defaultAllocator, 6);
+        auto b = WriteBuffer!ubyte(6);
         ubyte[6] buf = [23, 23, 255, 128, 127, 9];
-		void* returnedBuf;
 
         b ~= buf;
-		returnedBuf = b.buffer;
+        assert(b[0 .. $] == buf[0 .. 6]);
-		assert(returnedBuf[0..b.length] == buf[0..6]);
+        b += 2;
-		b.written = 2;
 
-		returnedBuf = b.buffer;
+        assert(b[0 .. $] == buf[2 .. 6]);
-		assert(returnedBuf[0..b.length] == buf[2..6]);
 
         b ~= buf;
-		returnedBuf = b.buffer;
+        assert(b[0 .. $] == buf[2 .. 6]);
-		assert(returnedBuf[0..b.length] == buf[2..6]);
+        b += b.length;
-		b.written = b.length;
 
-		returnedBuf = b.buffer;
+        assert(b[0 .. $] == buf[0 .. 6]);
-		assert(returnedBuf[0..b.length] == buf[0..6]);
+        b += b.length;
-		b.written = b.length;
-
-		finalize(defaultAllocator, b);
     }
+
+    /**
+     * After calling it, set $(D_KEYWORD +=) to the length could be
+     * written.
+     *
+     * $(D_PSYMBOL opIndex) may return only part of the data. You may need
+     * to call it and set $(D_KEYWORD +=) several times until
+     * $(D_PSYMBOL length) is 0. If all the data can be written,
+     * maximally 3 calls are required.
+     *
+     * Returns: A chunk of data buffer.
+     */
+    T[] opIndex()
+    {
+        return opSlice(0, length);
+    }
+
+    mixin DefaultAllocator;
+}
+
+private unittest
+{
+    static assert(is(typeof(WriteBuffer!int(5))));
 }

source/tanya/container/entry.d

@@ -0,0 +1,111 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * Internal package used by containers that rely on entries/nodes.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.container.entry;
+
+import std.traits;
+import tanya.typecons;
+
+package struct SEntry(T)
+{
+    // Item content.
+    T content;
+
+    // Next item.
+    SEntry* next;
+}
+
+package struct DEntry(T)
+{
+    // Item content.
+    T content;
+
+    // Previous and next item.
+    DEntry* next, prev;
+}
+
+package struct HashEntry(K, V)
+{
+    this(ref K key, ref V value)
+    {
+        this.pair = Pair!(K, V)(key, value);
+    }
+
+    Pair!(K, V) pair;
+    HashEntry* next;
+}
+
+package enum BucketStatus : byte
+{
+    deleted = -1,
+    empty = 0,
+    used = 1,
+}
+
+package struct Bucket(T)
+{
+    this(ref T content)
+    {
+        this.content = content;
+    }
+
+    @property void content(ref T content)
+    {
+        this.content_ = content;
+        this.status = BucketStatus.used;
+    }
+
+    @property ref inout(T) content() inout
+    {
+        return this.content_;
+    }
+
+    bool opEquals(ref T content)
+    {
+        if (this.status == BucketStatus.used && this.content == content)
+        {
+            return true;
+        }
+        return false;
+    }
+
+    bool opEquals(ref T content) const
+    {
+        if (this.status == BucketStatus.used && this.content == content)
+        {
+            return true;
+        }
+        return false;
+    }
+
+    bool opEquals(ref typeof(this) that)
+    {
+        return this.content == that.content && this.status == that.status;
+    }
+
+    bool opEquals(ref typeof(this) that) const
+    {
+        return this.content == that.content && this.status == that.status;
+    }
+
+    void remove()
+    {
+        static if (hasElaborateDestructor!T)
+        {
+            destroy(this.content);
+        }
+        this.status = BucketStatus.deleted;
+    }
+
+    T content_;
+    BucketStatus status = BucketStatus.empty;
+}

source/tanya/container/package.d

@@ -3,14 +3,40 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * Abstract data types whose instances are collections of other objects.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
  * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
 module tanya.container;
 
+public import tanya.container.array;
 public import tanya.container.buffer;
+public import tanya.container.set;
 public import tanya.container.list;
-public import tanya.container.vector;
+public import tanya.container.string;
 public import tanya.container.queue;
+
+/**
+ * Thrown if $(D_PSYMBOL Set) cannot insert a new element because the container
+ * is full.
+ */
+class HashContainerFullException : Exception
+{
+    /**
+     * Params:
+     *  msg  = The message for the exception.
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string msg,
+         string file = __FILE__,
+         size_t line = __LINE__,
+         Throwable next = null) @nogc @safe pure nothrow
+    {
+        super(msg, file, line, next);
+    }
+}

source/tanya/container/queue.d

@@ -3,104 +3,98 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * FIFO queue.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
  * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
 module tanya.container.queue;
 
+import core.exception;
+import std.traits;
+import std.algorithm.mutation;
+import tanya.container.entry;
 import tanya.memory;
 
 /**
- * Queue.
+ * FIFO queue.
  *
  * Params:
  *  T = Content type.
  */
-class Queue(T)
+struct Queue(T)
 {
-@nogc:
-	/**
-	 * Creates a new $(D_PSYMBOL Queue).
-	 *
-	 * Params:
-	 * 	allocator = The allocator should be used for the element
-	 * 	            allocations.
-	 */
-	this(Allocator allocator = defaultAllocator)
-	{
-		this.allocator = allocator;
-	}
-
     /**
      * Removes all elements from the queue.
      */
     ~this()
     {
-		foreach (e; this)
+        while (!empty)
         {
-            static if (isFinalizable!T)
+            dequeue();
-            {
-                finalize(allocator, e);
-            }
         }
     }
 
     /**
-	 * Returns: First element.
+     * Returns how many elements are in the queue. It iterates through the queue
+     * to count the elements.
+     *
+     * Returns: How many elements are in the queue.
      */
-	@property ref T front()
+    size_t length() const
-	in
     {
-		assert(!empty);
+        size_t len;
+        for (const(SEntry!T)* i = first; i !is null; i = i.next)
+        {
+            ++len;
         }
-	body
+        return len;
-	{
-		return first.next.content;
     }
 
-	/**
+    ///
-	 * Inserts a new element.
+    unittest
-	 *
-	 * Params:
-	 * 	x = New element.
-	 *
-	 * Returns: $(D_KEYWORD this).
-	 */
-	typeof(this) insertBack(T x)
     {
-		Entry* temp = make!Entry(allocator);
+        Queue!int q;
 
-		temp.content = x;
+        assert(q.length == 0);
+        q.enqueue(5);
+        assert(q.length == 1);
+        q.enqueue(4);
+        assert(q.length == 2);
+        q.enqueue(9);
+        assert(q.length == 3);
 
+        q.dequeue();
+        assert(q.length == 2);
+        q.dequeue();
+        assert(q.length == 1);
+        q.dequeue();
+        assert(q.length == 0);
+    }
+
+    private void enqueueEntry(ref SEntry!T* entry)
+    {
         if (empty)
         {
-			first.next = rear = temp;
+            first = rear = entry;
         }
         else
         {
-			rear.next = temp;
+            rear.next = entry;
             rear = rear.next;
         }
-
-		return this;
     }
 
-	alias insert = insertBack;
+    private SEntry!T* allocateEntry()
-
-	///
-	unittest
     {
-		auto q = make!(Queue!int)(defaultAllocator);
+        auto temp = cast(SEntry!T*) allocator.allocate(SEntry!T.sizeof);
-		int[2] values = [8, 9];
+        if (temp is null)
-
+        {
-		q.insertBack(values[0]);
+            onOutOfMemoryError();
-		assert(q.front is values[0]);
+        }
-		q.insertBack(values[1]);
+        return temp;
-		assert(q.front is values[0]);
-
-		finalize(defaultAllocator, q);
     }
 
     /**
@@ -108,112 +102,187 @@ class Queue(T)
      *
      * Params:
      *  x = New element.
-	 *
-	 * Returns: $(D_KEYWORD this).
      */
-	typeof(this) opOpAssign(string Op)(ref T x)
+    void enqueue(ref T x)
-		if (Op == "~")
     {
-		return insertBack(x);
+        auto temp = allocateEntry();
+
+        *temp = SEntry!T.init;
+        temp.content = x;
+
+        enqueueEntry(temp);
+    }
+
+    /// Ditto.
+    void enqueue(T x)
+    {
+        auto temp = allocateEntry();
+
+        moveEmplace(x, (*temp).content);
+        (*temp).next = null;
+
+        enqueueEntry(temp);
     }
 
     ///
     unittest
     {
-		auto q = make!(Queue!int)(defaultAllocator);
+        Queue!int q;
-		int value = 5;
 
         assert(q.empty);
-
+        q.enqueue(8);
-		q ~= value;
+        q.enqueue(9);
-
+        assert(q.dequeue() == 8);
-		assert(q.front == value);
+        assert(q.dequeue() == 9);
-		assert(!q.empty);
-
-		finalize(defaultAllocator, q);
     }
 
     /**
      * Returns: $(D_KEYWORD true) if the queue is empty.
      */
-	@property bool empty() const @safe pure nothrow
+    @property bool empty() const
     {
-		return first.next is null;
+        return first is null;
     }
 
     ///
     unittest
     {
-		auto q = make!(Queue!int)(defaultAllocator);
+        Queue!int q;
         int value = 7;
 
         assert(q.empty);
-		q.insertBack(value);
+        q.enqueue(value);
         assert(!q.empty);
-
-		finalize(defaultAllocator, q);
     }
 
     /**
-	 * Move position to the next element.
+     * Move the position to the next element.
      *
-	 * Returns: $(D_KEYWORD this).
+     * Returns: Dequeued element.
      */
-	typeof(this) popFront()
+    T dequeue()
     in
     {
         assert(!empty);
     }
     body
     {
-		auto n = first.next.next;
+        auto n = first.next;
+        T ret = move(first.content);
 
-		finalize(allocator, first.next);
+        allocator.dispose(first);
-		first.next = n;
+        first = n;
-
+        return ret;
-        return this;
     }
 
     ///
     unittest
     {
-		auto q = make!(Queue!int)(defaultAllocator);
+        Queue!int q;
-		int[2] values = [8, 9];
 
-		q.insertBack(values[0]);
+        q.enqueue(8);
-		q.insertBack(values[1]);
+        q.enqueue(9);
-		assert(q.front is values[0]);
+        assert(q.dequeue() == 8);
-		q.popFront();
+        assert(q.dequeue() == 9);
-		assert(q.front is values[1]);
-
-		finalize(defaultAllocator, q);
     }
 
     /**
-	 * Queue entry.
+     * $(D_KEYWORD foreach) iteration. The elements will be automatically
+     * dequeued.
+     *
+     * Params:
+     *  dg = $(D_KEYWORD foreach) body.
+     *
+     * Returns: The value returned from $(D_PARAM dg).
      */
-	protected struct Entry
+    int opApply(scope int delegate(ref size_t i, ref T) @nogc dg)
     {
-		/// Queue item content.
+        int result;
-		T content;
 
-		/// Next list item.
+        for (size_t i = 0; !empty; ++i)
-		Entry* next;
+        {
+            auto e = dequeue();
+            if ((result = dg(i, e)) != 0)
+            {
+                return result;
+            }
+        }
+        return result;
     }
 
-	/// The first element of the list.
+    /// Ditto.
-	protected Entry first;
+    int opApply(scope int delegate(ref T) @nogc dg)
+    {
+        int result;
 
-	/// The last element of the list.
+        while (!empty)
-	protected Entry* rear;
+        {
+            auto e = dequeue();
+            if ((result = dg(e)) != 0)
+            {
+                return result;
+            }
+        }
+        return result;
+    }
 
-	private Allocator allocator;
+    ///
+    unittest
+    {
+        Queue!int q;
+
+        size_t j;
+        q.enqueue(5);
+        q.enqueue(4);
+        q.enqueue(9);
+        foreach (i, e; q)
+        {
+            assert(i != 2 || e == 9);
+            assert(i != 1 || e == 4);
+            assert(i != 0 || e == 5);
+            ++j;
+        }
+        assert(j == 3);
+        assert(q.empty);
+
+        j = 0;
+        q.enqueue(5);
+        q.enqueue(4);
+        q.enqueue(9);
+        foreach (e; q)
+        {
+            assert(j != 2 || e == 9);
+            assert(j != 1 || e == 4);
+            assert(j != 0 || e == 5);
+            ++j;
+        }
+        assert(j == 3);
+        assert(q.empty);
+    }
+
+    private SEntry!T* first;
+    private SEntry!T* rear;
+
+    mixin DefaultAllocator;
 }
 
 ///
 unittest
 {
-	auto q = make!(Queue!int)(defaultAllocator);
+    Queue!int q;
 
-	finalize(defaultAllocator, q);
+    q.enqueue(5);
+    assert(!q.empty);
+
+    q.enqueue(4);
+    q.enqueue(9);
+
+    assert(q.dequeue() == 5);
+
+    foreach (i, ref e; q)
+    {
+        assert(i != 0 || e == 4);
+        assert(i != 1 || e == 9);
+    }
+    assert(q.empty);
 }

source/tanya/container/set.d

@@ -0,0 +1,710 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module implements a $(D_PSYMBOL Set) container that stores unique
+ * values without any particular order.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.container.set;
+
+import std.algorithm.mutation;
+import std.traits;
+import tanya.container;
+import tanya.container.entry;
+import tanya.memory;
+
+/**
+ * Bidirectional range that iterates over the $(D_PSYMBOL Set)'s values.
+ *
+ * Params:
+ *  E = Element type.
+ */
+struct Range(E)
+{
+    static if (isMutable!E)
+    {
+        private alias DataRange = Array!(Bucket!(Unqual!E)).Range;
+    }
+    else
+    {
+        private alias DataRange = Array!(Bucket!(Unqual!E)).ConstRange;
+    }
+    private DataRange dataRange;
+
+    @disable this();
+
+    private this(DataRange dataRange)
+    {
+        while (!dataRange.empty && dataRange.front.status != BucketStatus.used)
+        {
+            dataRange.popFront();
+        }
+        while (!dataRange.empty && dataRange.back.status != BucketStatus.used)
+        {
+            dataRange.popBack();
+        }
+        this.dataRange = dataRange;
+    }
+
+    @property Range save()
+    {
+        return this;
+    }
+
+    @property bool empty() const
+    {
+        return this.dataRange.empty();
+    }
+
+    @property void popFront()
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.front.status == BucketStatus.used);
+    }
+    out
+    {
+        assert(this.dataRange.empty
+            || this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        do
+        {
+            dataRange.popFront();
+        }
+        while (!dataRange.empty && dataRange.front.status != BucketStatus.used);
+    }
+
+    @property void popBack()
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.back.status == BucketStatus.used);
+    }
+    out
+    {
+        assert(this.dataRange.empty
+            || this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        do
+        {
+            dataRange.popBack();
+        }
+        while (!dataRange.empty && dataRange.back.status != BucketStatus.used);
+    }
+
+    @property ref inout(E) front() inout
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.front.status == BucketStatus.used);
+    }
+    body
+    {
+        return dataRange.front.content;
+    }
+
+    @property ref inout(E) back() inout
+    in
+    {
+        assert(!this.dataRange.empty);
+        assert(this.dataRange.back.status == BucketStatus.used);
+    }
+    body
+    {
+        return dataRange.back.content;
+    }
+
+    Range opIndex()
+    {
+        return typeof(return)(this.dataRange[]);
+    }
+
+    Range!(const E) opIndex() const
+    {
+        return typeof(return)(this.dataRange[]);
+    }
+}
+
+/**
+ * Set is a data structure that stores unique values without any particular
+ * order.
+ *
+ * This $(D_PSYMBOL Set) is implemented using closed hashing. Hash collisions
+ * are resolved with linear probing.
+ *
+ * Currently works only with integral types.
+ *
+ * Params:
+ *  T = Element type.
+ */
+struct Set(T)
+    if (isIntegral!T || is(Unqual!T == bool))
+{
+    /// The range types for $(D_PSYMBOL Set).
+    alias Range = .Range!T;
+
+    /// Ditto.
+    alias ConstRange = .Range!(const T);
+
+    invariant
+    {
+        assert(this.lengthIndex < primes.length);
+        assert(this.data.length == 0
+            || this.data.length == primes[this.lengthIndex]);
+    }
+
+    /**
+     * Constructor.
+     *
+     * Params:
+     *  n         = Minimum number of buckets.
+     *  allocator = Allocator.
+     *
+     * Precondition: $(D_INLINECODE allocator !is null).
+     */
+    this(const size_t n, shared Allocator allocator = defaultAllocator)
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this(allocator);
+        rehash(n);
+    }
+
+    /// Ditto.
+    this(shared Allocator allocator)
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.data = typeof(this.data)(allocator);
+    }
+
+    ///
+    unittest
+    {
+        {
+            auto set = Set!int(defaultAllocator);
+            assert(set.capacity == 0);
+        }
+        {
+            auto set = Set!int(8);
+            assert(set.capacity == 13);
+        }
+    }
+
+    /**
+     * Initializes this $(D_PARAM Set) from another one.
+     *
+     * If $(D_PARAM init) is passed by reference, it will be copied.
+     * If $(D_PARAM init) is passed by value, it will be moved.
+     *
+     * Params:
+     *  S         = Source set type.
+     *  init      = Source set.
+     *  allocator = Allocator.
+     */
+    this(S)(ref S init, shared Allocator allocator = defaultAllocator)
+        if (is(Unqual!S == Set))
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.data = typeof(this.data)(init.data, allocator);
+    }
+
+    /// Ditto.
+    this(S)(S init, shared Allocator allocator = defaultAllocator)
+        if (is(S == Set))
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.data = typeof(this.data)(move(init.data), allocator);
+        this.lengthIndex = init.lengthIndex;
+        init.lengthIndex = 0;
+    }
+
+    /**
+     * Assigns another set.
+     *
+     * If $(D_PARAM that) is passed by reference, it will be copied.
+     * If $(D_PARAM that) is passed by value, it will be moved.
+     *
+     * Params:
+     *  S    = Content type.
+     *  that = The value should be assigned.
+     *
+     * Returns: $(D_KEYWORD this).
+     */
+    ref typeof(this) opAssign(S)(ref S that)
+        if (is(Unqual!S == Set))
+    {
+        this.data = that.data;
+        this.lengthIndex = that.lengthIndex;
+        return this;
+    }
+
+    /// Ditto.
+    ref typeof(this) opAssign(S)(S that) @trusted
+        if (is(S == Set))
+    {
+        swap(this.data, that.data);
+        swap(this.lengthIndex, that.lengthIndex);
+        return this;
+    }
+
+    /**
+     * Returns: Used allocator.
+     *
+     * Postcondition: $(D_INLINECODE allocator !is null)
+     */
+    @property shared(Allocator) allocator() const
+    out (allocator)
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        return cast(shared Allocator) this.data.allocator;
+    }
+
+    /**
+     * Maximum amount of elements this $(D_PSYMBOL Set) can hold without
+     * resizing and rehashing. Note that it doesn't mean that the
+     * $(D_PSYMBOL Set) will hold $(I exactly) $(D_PSYMBOL capacity) elements.
+     * $(D_PSYMBOL capacity) tells the size of the container under a best-case
+     * distribution of elements.
+     *
+     * Returns: $(D_PSYMBOL Set) capacity.
+     */
+    @property size_t capacity() const
+    {
+        return this.data.length;
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+        assert(set.capacity == 0);
+
+        set.insert(8);
+        assert(set.capacity == 3);
+    }
+
+    /**
+     * Iterates over the $(D_PSYMBOL Set) and counts the elements.
+     *
+     * Returns: Count of elements within the $(D_PSYMBOL Set).
+     */
+    @property size_t length() const
+    {
+        size_t count;
+        foreach (ref e; this.data[])
+        {
+            if (e.status == BucketStatus.used)
+            {
+                ++count;
+            }
+        }
+        return count;
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+        assert(set.length == 0);
+
+        set.insert(8);
+        assert(set.length == 1);
+    }
+
+    private static const size_t[41] primes = [
+        3, 7, 13, 23, 29, 37, 53, 71, 97, 131, 163, 193, 239, 293, 389, 521,
+        769, 919, 1103, 1327, 1543, 2333, 3079, 4861, 6151, 12289, 24593,
+        49157, 98317, 196613, 393241, 786433, 1572869, 3145739, 6291469,
+        12582917, 25165843, 139022417, 282312799, 573292817, 1164186217,
+    ];
+
+    /// The maximum number of buckets the container can have.
+    enum size_t maxBucketCount = primes[$ - 1];
+
+    static private size_t calculateHash(ref T value)
+    {
+        static if (isIntegral!T || isSomeChar!T || is(T == bool))
+        {
+            return (cast(size_t) value);
+        }
+        else
+        {
+            static assert(false);
+        }
+    }
+
+    static private size_t locateBucket(ref const DataType buckets, size_t hash)
+    {
+        return hash % buckets.length;
+    }
+
+    private enum InsertStatus : byte
+    {
+        found = -1,
+        failed = 0,
+        added = 1,
+    }
+
+    /*
+     * Inserts the value in an empty or deleted bucket. If the value is
+     * already in there, does nothing and returns InsertStatus.found. If the
+     * hash array is full returns InsertStatus.failed.
+     */
+    private InsertStatus insertInUnusedBucket(ref T value)
+    {
+        auto bucketPosition = locateBucket(this.data, calculateHash(value));
+
+        foreach (ref e; this.data[bucketPosition .. $])
+        {
+            if (e == value) // Already in the set.
+            {
+                return InsertStatus.found;
+            }
+            else if (e.status != BucketStatus.used) // Insert the value.
+            {
+                e.content = value;
+                return InsertStatus.added;
+            }
+        }
+        return InsertStatus.failed;
+    }
+
+    /**
+     * Inserts a new element.
+     *
+     * Params:
+     *  value = Element value.
+     *
+     * Returns: Amount of new elements inserted.
+     *
+     * Throws: $(D_PSYMBOL HashContainerFullException) if the insertion failed.
+     */
+    size_t insert(T value)
+    {
+        if (this.data.length == 0)
+        {
+            this.data = DataType(primes[0], allocator);
+        }
+
+        InsertStatus status = insertInUnusedBucket(value);
+        for (; !status; status = insertInUnusedBucket(value))
+        {
+            if ((this.primes.length - 1) == this.lengthIndex)
+            {
+                throw make!HashContainerFullException(defaultAllocator,
+                                                      "Set is full");
+            }
+            rehashToSize(this.lengthIndex + 1);
+        }
+        return status == InsertStatus.added;
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+        assert(8 !in set);
+
+        assert(set.insert(8) == 1);
+        assert(set.length == 1);
+        assert(8 in set);
+
+        assert(set.insert(8) == 0);
+        assert(set.length == 1);
+        assert(8 in set);
+
+        assert(set.remove(8));
+        assert(set.insert(8) == 1);
+    }
+
+    /**
+     * Removes an element.
+     *
+     * Params:
+     *  value = Element value.
+     *
+     * Returns: Number of elements removed, which is in the container with
+     *          unique values `1` if an element existed, and `0` otherwise.
+     */
+    size_t remove(T value)
+    {
+        if (this.data.length == 0)
+        {
+            return 0;
+        }
+
+        auto bucketPosition = locateBucket(this.data, calculateHash(value));
+        foreach (ref e; this.data[bucketPosition .. $])
+        {
+            if (e == value) // Found.
+            {
+                e.remove();
+                return 1;
+            }
+            else if (e.status == BucketStatus.empty)
+            {
+                break;
+            }
+        }
+        return 0;
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+        assert(8 !in set);
+
+        set.insert(8);
+        assert(8 in set);
+
+        assert(set.remove(8) == 1);
+        assert(set.remove(8) == 0);
+        assert(8 !in set);
+    }
+
+    /**
+     * $(D_KEYWORD in) operator.
+     *
+     * Params:
+     *  value = Element to be searched for.
+     *
+     * Returns: $(D_KEYWORD true) if the given element exists in the container,
+     *          $(D_KEYWORD false) otherwise.
+     */
+    bool opBinaryRight(string op : "in")(auto ref T value)
+    {
+        if (this.data.length == 0)
+        {
+            return 0;
+        }
+
+        auto bucketPosition = locateBucket(this.data, calculateHash(value));
+        foreach (ref e; this.data[bucketPosition .. $])
+        {
+            if (e == value) // Found.
+            {
+                return true;
+            }
+            else if (e.status == BucketStatus.empty)
+            {
+                break;
+            }
+        }
+        return false;
+    }
+
+    /// Ditto.
+    bool opBinaryRight(string op : "in")(auto ref const T value) const
+    {
+        if (this.data.length == 0)
+        {
+            return 0;
+        }
+
+        auto bucketPosition = locateBucket(this.data, calculateHash(value));
+        foreach (ref e; this.data[bucketPosition .. $])
+        {
+            if (e.status == BucketStatus.used && e.content == value) // Found.
+            {
+                return true;
+            }
+            else if (e.status == BucketStatus.empty)
+            {
+                break;
+            }
+        }
+        return false;
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+
+        assert(5 !in set);
+        set.insert(5);
+        assert(5 in set);
+    }
+
+    /**
+     * Sets the number of buckets in the container to at least $(D_PARAM n)
+     * and rearranges all the elements according to their hash values.
+     *
+     * If $(D_PARAM n) is greater than the current $(D_PSYMBOL capacity)
+     * and lower than or equal to $(D_PSYMBOL maxBucketCount), a rehash is
+     * forced.
+     *
+     * If $(D_PARAM n) is greater than $(D_PSYMBOL maxBucketCount),
+     * $(D_PSYMBOL maxBucketCount) is used instead as a new number of buckets.
+     *
+     * If $(D_PARAM n) is equal to the current $(D_PSYMBOL capacity), rehashing
+     * is forced without resizing the container.
+     *
+     * If $(D_PARAM n) is lower than the current $(D_PSYMBOL capacity), the
+     * function may have no effect.
+     *
+     * Rehashing is automatically performed whenever the container needs space
+     * to insert new elements.
+     *
+     * Params:
+     *  n = Minimum number of buckets.
+     */
+    void rehash(const size_t n)
+    {
+        size_t lengthIndex;
+        for (; lengthIndex < primes.length; ++lengthIndex)
+        {
+            if (primes[lengthIndex] >= n)
+            {
+                break;
+            }
+        }
+        rehashToSize(lengthIndex);
+    }
+
+    // Takes an index in the primes array.
+    private void rehashToSize(const size_t n)
+    {
+        auto storage = DataType(primes[n], allocator);
+        DataLoop: foreach (ref e1; this.data[])
+        {
+            if (e1.status == BucketStatus.used)
+            {
+                auto bucketPosition = locateBucket(storage,
+                                                   calculateHash(e1.content));
+
+                foreach (ref e2; storage[bucketPosition .. $])
+                {
+                    if (e2.status != BucketStatus.used) // Insert the value.
+                    {
+                        e2.content = e1.content;
+                        continue DataLoop;
+                    }
+                }
+                return; // Rehashing failed.
+            }
+        }
+        move(storage, this.data);
+        this.lengthIndex = n;
+    }
+
+    /**
+     * Returns: A bidirectional range that iterates over the $(D_PSYMBOL Set)'s
+     *          elements.
+     */
+    Range opIndex()
+    {
+        return typeof(return)(this.data[]);
+    }
+
+    /// Ditto.
+    ConstRange opIndex() const
+    {
+        return typeof(return)(this.data[]);
+    }
+
+    ///
+    unittest
+    {
+        Set!int set;
+        assert(set[].empty);
+
+        set.insert(8);
+        assert(!set[].empty);
+        assert(set[].front == 8);
+        assert(set[].back == 8);
+
+        set.remove(8);
+        assert(set[].empty);
+    }
+
+    private alias DataType = Array!(Bucket!T);
+    private DataType data;
+    private size_t lengthIndex;
+}
+
+// Basic insertion logic.
+private unittest
+{
+    Set!int set;
+
+    assert(set.insert(5) == 1);
+    assert(set.data[0].status == BucketStatus.empty);
+    assert(set.data[1].status == BucketStatus.empty);
+    assert(set.data[2].content == 5 && set.data[2].status == BucketStatus.used);
+    assert(set.data.length == 3);
+
+    assert(set.insert(5) == 0);
+    assert(set.data[0].status == BucketStatus.empty);
+    assert(set.data[1].status == BucketStatus.empty);
+    assert(set.data[2].content == 5 && set.data[2].status == BucketStatus.used);
+    assert(set.data.length == 3);
+
+    assert(set.insert(9) == 1);
+    assert(set.data[0].content == 9 && set.data[0].status == BucketStatus.used);
+    assert(set.data[1].status == BucketStatus.empty);
+    assert(set.data[2].content == 5 && set.data[2].status == BucketStatus.used);
+    assert(set.data.length == 3);
+
+    assert(set.insert(7) == 1);
+    assert(set.insert(8) == 1);
+    assert(set.data[0].content == 7);
+    assert(set.data[1].content == 8);
+    assert(set.data[2].content == 9);
+    assert(set.data[3].status == BucketStatus.empty);
+    assert(set.data[5].content == 5);
+    assert(set.data.length == 7);
+
+    assert(set.insert(16) == 1);
+    assert(set.data[2].content == 9);
+    assert(set.data[3].content == 16);
+    assert(set.data[4].status == BucketStatus.empty);
+}
+
+// Static checks.
+private unittest
+{
+    import std.range.primitives;
+
+    static assert(isBidirectionalRange!(Set!int.ConstRange));
+    static assert(isBidirectionalRange!(Set!int.Range));
+
+    static assert(!isInfinite!(Set!int.Range));
+    static assert(!hasLength!(Set!int.Range));
+
+    static assert(is(Set!uint));
+    static assert(is(Set!long));
+    static assert(is(Set!ulong));
+    static assert(is(Set!short));
+    static assert(is(Set!ushort));
+    static assert(is(Set!bool));
+}

source/tanya/container/vector.d

@@ -1,420 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
- */  
-module tanya.container.vector;
-
-import tanya.memory;
-
-@nogc:
-
-/**
- * One dimensional array. It allocates automatically if needed.
- *
- * If you assign a value:
- * ---
- * auto v = make!(Vector!int)(defaultAllocator);
- * int value = 5;
- *
- * v[1000] = value;
- *
- * finalize(defaultAllocator, v);
- * ---
- * it will allocate not only for one, but for 1000 elements. So this
- * implementation is more suitable for sequential data with random access.
- *
- * Params:
- * 	T = Content type.
- */
-class Vector(T)
-{
-@nogc:
-	/**
-	 * Creates a new $(D_PSYMBOL Vector).
-	 *
-	 * Params:
-	 * 	length    = Initial length.
-	 * 	allocator = The allocator should be used for the element
-	 * 	            allocations.
-	 */
-	this(size_t length, Allocator allocator = defaultAllocator)
-	{
-		this.allocator = allocator;
-		vector = makeArray!T(allocator, length);
-	}
-
-	/// Ditto.
-	this(Allocator allocator = defaultAllocator)
-	{
-		this(0, allocator);
-	}
-
-	/**
-	 * Removes all elements from the vector.
-	 */
-	~this()
-	{
-		finalize(allocator, vector);
-	}
-
-	/**
-	 * Returns: Vector length.
-	 */
-	@property size_t length() const
-	{
-		return vector.length;
-	}
-
-	/**
-	 * Expans/shrinks the vector.
-	 *
-	 * Params:
-	 * 	length = New length.
-	 */
-	@property void length(size_t length)
-	{
-		resizeArray!T(allocator, vector, length);
-	}
-
-    ///
-    unittest
-    {
-        auto v = make!(Vector!int)(defaultAllocator);
-
-        v.length = 5;
-        assert(v.length == 5);
-
-		// TODO
-        v.length = 7;
-        assert(v.length == 7);
-
-        v.length = 0;
-        assert(v.length == 0);
-
-        finalize(defaultAllocator, v);
-    }
-
-	/**
-	 * Returns: $(D_KEYWORD true) if the vector is empty.
-	 */
-	@property bool empty() const
-	{
-		return length == 0;
-	}
-
-	static if (isFinalizable!T)
-	{
-		/**
-		 * Removes an elements from the vector.
-		 *
-		 * Params:
-		 * 	pos = Element index.
-		 */
-		void remove(size_t pos)
-		{
-			auto el = vector[pos];
-			finalize(allocator, el);
-		}
-	}
-
-	/**
-	 * Assigns a value. Allocates if needed.
-	 *
-	 * Params:
-	 * 	value = Value.
-	 *
-	 * Returns: Assigned value.
-	 */
-	T opIndexAssign(T value, size_t pos)
-	{
-		if (pos >= length)
-		{
-			resizeArray!T(allocator, vector, pos + 1);
-		}
-		return vector[pos] = value;
-	}
-
-	///
-	unittest
-	{
-        auto v = make!(Vector!int)(defaultAllocator);
-        int[2] values = [5, 15];
-
-		assert(v.length == 0);
-		v[1] = values[0];
-		assert(v.length == 2);
-		v[3] = values[0];
-		assert(v.length == 4);
-		v[4] = values[1];
-		assert(v.length == 5);
-
-        finalize(defaultAllocator, v);
-	}
-
-	/**
-	 * Returns: The value on index $(D_PARAM pos).
-	 */
-	ref T opIndex(in size_t pos)
-	in
-	{
-		assert(length > pos);
-	}
-	body
-	{
-		return vector[pos];
-	}
-
-	///
-	unittest
-	{
-        auto v = make!(Vector!int)(defaultAllocator);
-        int[2] values = [5, 15];
-
-		v[1] = values[0];
-		assert(v[1] is values[0]);
-		v[3] = values[0];
-		assert(v[3] is values[0]);
-		v[4] = values[1];
-		assert(v[4] is values[1]);
-		v[0] = values[1];
-		assert(v[0] is values[1]);
-
-        finalize(defaultAllocator, v);
-	}
-
-	/**
-	 * $(D_KEYWORD foreach) iteration.
-	 *
-	 * Params:
-	 * 	dg = $(D_KEYWORD foreach) body.
-	 */
-	int opApply(int delegate(ref T) @nogc dg)
-	{
-		int result;
-
-		foreach (e; vector)
-		{
-			result = dg(e);
-
-			if (result != 0)
-			{
-				return result;
-			}
-		}
-		return result;
-	}
-
-	/// Ditto.
-	int opApply(int delegate(ref size_t i, ref T) @nogc dg)
-	{
-		int result;
-
-		foreach (i, e; vector)
-		{
-			result = dg(i, e);
-
-			if (result != 0)
-			{
-				return result;
-			}
-		}
-		return result;
-	}
-
-	///
-	unittest
-	{
-        auto v = make!(Vector!int)(defaultAllocator, 1);
-        int[3] values = [5, 15, 8];
-
-        v[0] = values[0];
-        v[1] = values[1];
-        v[2] = values[2];
-
-		int i;
-		foreach (e; v)
-		{
-			assert(i != 0 || e is values[0]);
-			assert(i != 1 || e is values[1]);
-			assert(i != 2 || e is values[2]);
-			++i;
-		}
-
-		foreach (j, e; v)
-		{
-			assert(j != 0 || e is values[0]);
-			assert(j != 1 || e is values[1]);
-			assert(j != 2 || e is values[2]);
-		}
-
-        finalize(defaultAllocator, v);
-	}
-
-	/**
-	 * Sets the first element. Allocates if the vector is empty.
-     *
-     * Params:
-     *  x = New element.
-     */
-	@property void front(ref T x)
-	{
-		this[0] = x;
-	}
-
-	/**
-	 * Returns: The first element.
-     */
-	@property ref inout(T) front() inout
-    in
-	{
-		assert(!empty);
-	}
-	body
-	{
-		return vector[0];
-	}
-
-    ///
-    unittest
-    {
-        auto v = make!(Vector!int)(defaultAllocator, 1);
-        int[2] values = [5, 15];
-
-        v.front = values[0];
-        assert(v.front == 5);
-
-        v.front = values[1];
-        assert(v.front == 15);
-
-        finalize(defaultAllocator, v);
-    }
-
-	/**
-	 * Move position to the next element.
-	 *
-	 * Returns: $(D_KEYWORD this).
-	 */
-	typeof(this) popFront()
-	in
-	{
-		assert(!empty);
-	}
-	body
-	{
-		vector[0 .. $ - 1] = vector[1..$];
-		resizeArray(allocator, vector, length - 1);
-		return this;
-	}
-
-	///
-	unittest
-	{
-        auto v = make!(Vector!int)(defaultAllocator, 1);
-        int[2] values = [5, 15];
-
-        v[0] = values[0];
-        v[1] = values[1];
-        assert(v.front is values[0]);
-        assert(v.length == 2);
-		v.popFront();
-        assert(v.front is values[1]);
-        assert(v.length == 1);
-		v.popFront();
-        assert(v.empty);
-
-        finalize(defaultAllocator, v);
-	}
-
-	/**
-	 * Sets the last element. Allocates if the vector is empty.
-     *
-     * Params:
-     *  x = New element.
-     */
-	@property void back(ref T x)
-	{
-		vector[empty ? 0 : $ - 1] = x;
-	}
-
-	/**
-	 * Returns: The last element.
-     */
-	@property ref inout(T) back() inout
-    in
-	{
-		assert(!empty);
-	}
-	body
-	{
-		return vector[$ - 1];
-	}
-
-    ///
-    unittest
-    {
-        auto v = make!(Vector!int)(defaultAllocator, 1);
-        int[2] values = [5, 15];
-
-        v.back = values[0];
-        assert(v.back == 5);
-
-        v.back = values[1];
-        assert(v.back == 15);
-
-        finalize(defaultAllocator, v);
-    }
-
-	/**
-	 * Move position to the previous element.
-	 *
-	 * Returns: $(D_KEYWORD this).
-	 */
-	typeof(this) popBack()
-	in
-	{
-		assert(!empty);
-	}
-	body
-	{
-		resizeArray(allocator, vector, length - 1);
-		return this;
-	}
-
-	///
-	unittest
-	{
-        auto v = make!(Vector!int)(defaultAllocator, 1);
-        int[2] values = [5, 15];
-
-        v[0] = values[0];
-        v[1] = values[1];
-        assert(v.back is values[1]);
-        assert(v.length == 2);
-		v.popBack();
-        assert(v.back is values[0]);
-        assert(v.length == 1);
-		v.popBack();
-        assert(v.empty);
-
-        finalize(defaultAllocator, v);
-	}
-
-	/// Container.
-	protected T[] vector;
-
-	private Allocator allocator;
-}
-
-///
-unittest
-{
-	auto v = make!(Vector!int)(defaultAllocator);
-
-	finalize(defaultAllocator, v);
-}

source/tanya/crypto/padding.d

@@ -1,191 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.crypto.padding;
-
-import tanya.memory;
-import std.algorithm.iteration;
-import std.typecons;
-
-@nogc:
-
-/**
- * Supported padding mode.
- *
- * See_Also:
- * 	$(D_PSYMBOL applyPadding)
- */
-enum Mode
-{
-	zero,
-	pkcs7,
-	ansiX923,
-}
-
-/**
- * Params:
- * 	allocator = Allocator that should be used if the block should be extended
- * 	            or a new block should be added.
- * 	input     = Sequence that should be padded.
- * 	mode      = Padding mode.
- * 	blockSize = Block size.
- *
- * Returns: The functions modifies the initial array and returns it.
- *
- * See_Also:
- * 	$(D_PSYMBOL Mode)
- */
-ubyte[] applyPadding(ref ubyte[] input,
-                     in Mode mode,
-                     in ushort blockSize,
-                     Allocator allocator = defaultAllocator)
-in
-{
-	assert(blockSize > 0 && blockSize <= 256);
-	assert(blockSize % 64 == 0);
-	assert(input.length > 0);
-}
-body
-{
-	immutable rest = cast(ubyte) input.length % blockSize;
-	immutable size_t lastBlock = input.length - (rest > 0 ? rest : blockSize);
-	immutable needed = cast(ubyte) (rest > 0 ? blockSize - rest : 0);
-
-	final switch (mode) with (Mode)
-	{
-		case zero:
-			allocator.expandArray(input, needed);
-			break;
-		case pkcs7:
-			if (needed)
-			{
-				allocator.expandArray(input, needed);
-				input[input.length - needed ..$].each!((ref e) => e = needed);
-			}
-			else
-			{
-				allocator.expandArray(input, blockSize);
-			}
-			break;
-		case ansiX923:
-			allocator.expandArray(input, needed ? needed : blockSize);
-			input[$ - 1] = needed;
-			break;
-	}
-
-	return input;
-}
-
-///
-unittest
-{
-	{ // Zeros
-		auto input = defaultAllocator.makeArray!ubyte(50);
-
-		applyPadding(input, Mode.zero, 64);
-		assert(input.length == 64);
-
-		applyPadding(input, Mode.zero, 64);
-		assert(input.length == 64);
-		assert(input[63] == 0);
-
-		defaultAllocator.finalize(input);
-	}
-	{ // PKCS#7
-		auto input = defaultAllocator.makeArray!ubyte(50);
-		for (ubyte i; i < 40; ++i)
-		{
-			input[i] = i;
-		}
-
-		applyPadding(input, Mode.pkcs7, 64);
-		assert(input.length == 64);
-		for (ubyte i; i < 64; ++i)
-		{
-			if (i >= 40 && i < 50)
-			{
-				assert(input[i] == 0);
-			}
-			else if (i >= 50)
-			{
-				assert(input[i] == 14);
-			}
-			else
-			{
-				assert(input[i] == i);
-			}
-		}
-
-		applyPadding(input, Mode.pkcs7, 64);
-		assert(input.length == 128);
-		for (ubyte i; i < 128; ++i)
-		{
-			if (i >= 64 || (i >= 40 && i < 50))
-			{
-				assert(input[i] == 0);
-			}
-			else if (i >= 50 && i < 64)
-			{
-				assert(input[i] == 14);
-			}
-			else
-			{
-				assert(input[i] == i);
-			}
-		}
-
-		defaultAllocator.finalize(input);
-	}
-	{ // ANSI X.923
-		auto input = defaultAllocator.makeArray!ubyte(50);
-		for (ubyte i; i < 40; ++i)
-		{
-			input[i] = i;
-		}
-
-		applyPadding(input, Mode.ansiX923, 64);
-		assert(input.length == 64);
-		for (ubyte i; i < 64; ++i)
-		{
-			if (i < 40)
-			{
-				assert(input[i] == i);
-			}
-			else if (i == 63)
-			{
-				assert(input[i] == 14);
-			}
-			else
-			{
-				assert(input[i] == 0);
-			}
-		}
-
-		applyPadding(input, Mode.pkcs7, 64);
-		assert(input.length == 128);
-		for (ubyte i = 0; i < 128; ++i)
-		{
-			if (i < 40)
-			{
-				assert(input[i] == i);
-			}
-			else if (i == 63)
-			{
-				assert(input[i] == 14);
-			}
-			else
-			{
-				assert(input[i] == 0);
-			}
-		}
-
-		defaultAllocator.finalize(input);
-	}
-}

source/tanya/event/internal/epoll.d

@@ -1,226 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.internal.epoll;
-
-import tanya.event.config;
-
-static if (UseEpoll):
-
-public import core.sys.linux.epoll;
-import tanya.event.internal.selector;
-import tanya.event.protocol;
-import tanya.event.transport;
-import tanya.event.watcher;
-import tanya.event.loop;
-import tanya.container.list;
-import tanya.memory;
-import core.stdc.errno;
-import core.sys.posix.fcntl;
-import core.sys.posix.netinet.in_;
-import core.time;
-import std.algorithm.comparison;
-
-@nogc:
-
-extern (C) nothrow
-{ // TODO: Make a pull request for Phobos to mark this extern functions as @nogc.
-    int epoll_create1(int __flags);
-    int epoll_ctl(int __epfd, int __op, int __fd, epoll_event *__event);
-    int epoll_wait(int __epfd, epoll_event *__events, int __maxevents, int __timeout);
-	int accept4(int, sockaddr*, socklen_t*, int flags);
-}
-
-private enum maxEvents = 128;
-
-class EpollLoop : Loop
-{
-@nogc:
-	/**
-	 * Initializes the loop.
-	 */
-	this()
-	{
-		super();
-
-		if ((fd = epoll_create1(EPOLL_CLOEXEC)) < 0)
-		{
-			return;
-		}
-		epollEvents = makeArray!epoll_event(defaultAllocator, maxEvents).ptr;
-	}
-
-	/**
-	 * Frees loop internals.
-	 */
-	~this()
-	{
-		finalize(defaultAllocator, epollEvents);
-	}
-
-	/**
-	 * Should be called if the backend configuration changes.
-	 *
-	 * Params:
-	 * 	socket    = Socket.
-	 * 	oldEvents = The events were already set.
-	 * 	events    = The events should be set.
-	 *
-	 * Returns: $(D_KEYWORD true) if the operation was successful.
-	 */
-	protected override bool modify(int socket, EventMask oldEvents, EventMask events)
-	{
-		int op = EPOLL_CTL_DEL;
-		epoll_event ev;
-
-		if (events == oldEvents)
-		{
-			return true;
-		}
-		if (events && oldEvents)
-		{
-			op = EPOLL_CTL_MOD;
-		}
-		else if (events && !oldEvents)
-		{
-			op = EPOLL_CTL_ADD;
-		}
-
-		ev.data.fd = socket;
-		ev.events = (events & (Event.read | Event.accept) ? EPOLLIN | EPOLLPRI : 0)
-		          | (events & Event.write ? EPOLLOUT : 0)
-		          | EPOLLET;
-
-		return epoll_ctl(fd, op, socket, &ev) == 0;
-	}
-
-	/**
-	 * Accept incoming connections.
-	 *
-	 * Params:
-	 * 	protocolFactory = Protocol factory.
-	 * 	socket          = Socket.
-	 */
-	protected override void acceptConnection(Protocol delegate() @nogc protocolFactory,
-	                                         int socket)
-	{
-		sockaddr_in client_addr;
-		socklen_t client_len = client_addr.sizeof;
-		int client = accept4(socket,
-		                     cast(sockaddr *)&client_addr,
-		                     &client_len,
-		                     O_NONBLOCK);
-		while (client >= 0)
-		{
-			auto transport = make!SocketTransport(defaultAllocator, this, client);
-			IOWatcher connection;
-
-			if (connections.length > client)
-			{
-				connection = cast(IOWatcher) connections[client];
-				// If it is a ConnectionWatcher
-				if (connection is null && connections[client] !is null)
-				{
-					finalize(defaultAllocator, connections[client]);
-					connections[client] = null;
-				}
-			}
-			if (connection !is null)
-			{
-				connection(protocolFactory, transport);
-			}
-			else
-			{
-				connections[client] = make!IOWatcher(defaultAllocator,
-				                                     protocolFactory,
-				                                     transport);
-			}
-
-			modify(client, EventMask(Event.none), EventMask(Event.read, Event.write));
-
-			swapPendings.insertBack(connections[client]);
-
-			client = accept4(socket,
-			                 cast(sockaddr *)&client_addr,
-			                 &client_len,
-			                 O_NONBLOCK);
-		}
-	}
-
-	/**
-	 * Does the actual polling.
-	 */
-	protected override void poll()
-	{
-		// Don't block
-		immutable timeout = cast(immutable int) blockTime.total!"msecs";
-		auto eventCount = epoll_wait(fd, epollEvents, maxEvents, timeout);
-
-		if (eventCount < 0)
-		{
-			if (errno != EINTR)
-			{
-				throw make!BadLoopException(defaultAllocator);
-			}
-
-			return;
-		}
-
-		for (auto i = 0; i < eventCount; ++i)
-		{
-			epoll_event *ev = epollEvents + i;
-			auto connection = cast(IOWatcher) connections[ev.data.fd];
-
-			if (connection is null)
-			{
-				swapPendings.insertBack(connections[ev.data.fd]);
-//				acceptConnection(connections[ev.data.fd].protocol,
-//				                 connections[ev.data.fd].socket);
-			}
-			else
-			{
-				auto transport = cast(SocketTransport) connection.transport;
-				assert(transport !is null);
-
-				if (ev.events & (EPOLLIN | EPOLLPRI | EPOLLERR | EPOLLHUP))
-				{
-					try
-					{
-						while (!transport.receive())
-						{
-						}
-						swapPendings.insertBack(connection);
-					}
-					catch (TransportException e)
-					{
-						swapPendings.insertBack(connection);
-						finalize(defaultAllocator, e);
-					}
-				}
-				else if (ev.events & (EPOLLOUT | EPOLLERR | EPOLLHUP))
-				{
-					transport.writeReady = true;
-				}
-			}
-		}
-	}
-
-	/**
-	 * Returns: The blocking time.
-	 */
-	override protected @property inout(Duration) blockTime()
-	inout @safe pure nothrow
-	{
-		return min(super.blockTime, 1.dur!"seconds");
-	}
-
-	private int fd;
-	private epoll_event* epollEvents;
-}

source/tanya/event/internal/selector.d

@@ -1,217 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.internal.selector;
-
-import tanya.memory;
-import tanya.container.buffer;
-import tanya.event.loop;
-import tanya.event.protocol;
-import tanya.event.transport;
-import core.stdc.errno;
-import core.sys.posix.netinet.in_;
-import core.sys.posix.unistd;
-
-/**
- * Transport for stream sockets.
- */
-class SocketTransport : DuplexTransport
-{
-@nogc:
-	private int socket_ = -1;
-
-	private Protocol protocol_;
-
-	/// Input buffer.
-	private WriteBuffer input_;
-
-	/// Output buffer.
-	private ReadBuffer output_;
-
-	private Loop loop;
-
-	private bool disconnected_;
-
-	package bool writeReady;
-
-	/**
-	 * Params:
-	 * 	loop     = Event loop.
-	 * 	socket   = Socket.
-	 * 	protocol = Protocol.
-	 */
-	this(Loop loop, int socket, Protocol protocol = null)
-	{
-		socket_ = socket;
-		protocol_ = protocol;
-		this.loop = loop;
-		input_ = make!WriteBuffer(defaultAllocator);
-		output_ = make!ReadBuffer(defaultAllocator);
-	}
-
-	/**
-	 * Close the transport and deallocate the data buffers.
-	 */
-	~this()
-	{
-		close(socket);
-		finalize(defaultAllocator, input_);
-		finalize(defaultAllocator, output_);
-		finalize(defaultAllocator, protocol_);
-	}
-
-	/**
-	 * Returns: Transport socket.
-	 */
-	int socket() const @safe pure nothrow
-	{
-		return socket_;
-	}
-
-	/**
-	 * Returns: Protocol.
-	 */
-	@property Protocol protocol() @safe pure nothrow
-	{
-		return protocol_;
-	}
-
-	/**
-	 *  Returns: $(D_KEYWORD true) if the remote peer closed the connection,
-	 *           $(D_KEYWORD false) otherwise.
-	 */
-	@property immutable(bool) disconnected() const @safe pure nothrow
-	{
-		return disconnected_;
-	}
-
-	/**
-	 * Params:
-	 * 	protocol = Application protocol.
-	 */
-	@property void protocol(Protocol protocol) @safe pure nothrow
-	{
-		protocol_ = protocol;
-	}
-
-	/**
-	 * Returns: Application protocol.
-	 */
-	@property inout(Protocol) protocol() inout @safe pure nothrow
-	{
-		return protocol_;
-	}
-
-	/**
-	 * Write some data to the transport.
-	 *
-	 * Params:
-	 * 	data = Data to send.
-	 */
-	void write(ubyte[] data)
-	{
-		// If the buffer wasn't empty the transport should be already there.
-		if (!input.length && data.length)
-		{
-			loop.feed(this);
-		}
-		input ~= data;
-	}
-
-	/**
-	 * Returns: Input buffer.
-	 */
-	@property WriteBuffer input() @safe pure nothrow
-	{
-		return input_;
-	}
-
-	/**
-	 * Returns: Output buffer.
-	 */
-	@property ReadBuffer output() @safe pure nothrow
-	{
-		return output_;
-	}
-
-	/**
-	 * Read data from the socket. Returns $(D_KEYWORD true) if the reading
-	 * is completed. In the case that the peer closed the connection, returns
-	 * $(D_KEYWORD true) aswell.
-	 *
-	 * Returns: Whether the reading is completed.
-	 *
-	 * Throws: $(D_PSYMBOL TransportException) if a read error is occured.
-	 */
-	bool receive()
-	{
-		auto readCount = recv(socket, output.buffer, output.free, 0);
-
-		if (readCount > 0)
-		{
-			output_ ~= output.buffer[0..readCount];
-			return false;
-		}
-		else if (readCount == 0)
-		{
-			disconnected_ = true;
-			return true;
-		}
-		else if (errno == EAGAIN || errno == EWOULDBLOCK)
-		{
-			return true;
-		}
-		else
-		{
-			disconnected_ = true;
-			throw make!TransportException(defaultAllocator,
-			                              "Read from the socket failed.");
-		}
-	}
-
-	/**
-	 * Returns: Whether the writing is completed.
-	 *
-	 * Throws: $(D_PSYMBOL TransportException) if a read error is occured.
-	 */
-	bool send()
-	{
-		auto sentCount = core.sys.posix.netinet.in_.send(socket,
-		                                                 input.buffer,
-		                                                 input.length,
-		                                                 0);
-
-		input.written = sentCount;
-		if (input.length == 0)
-		{
-			return true;
-		}
-		else if (sentCount >= 0)
-		{
-			loop.feed(this);
-
-			return false;
-		}
-		else if (errno == EAGAIN || errno == EWOULDBLOCK)
-		{
-			writeReady = false;
-			loop.feed(this);
-
-			return false;
-		}
-		else
-		{
-			disconnected_ = true;
-			loop.feed(this);
-			throw make!TransportException(defaultAllocator,
-			                              "Write to the socket failed.");
-		}
-	}
-}

source/tanya/event/loop.d

@@ -1,279 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.loop;
-
-import tanya.memory;
-import tanya.container.queue;
-import tanya.container.vector;
-import tanya.event.config;
-import tanya.event.protocol;
-import tanya.event.transport;
-import tanya.event.watcher;
-import tanya.container.buffer;
-import core.thread;
-import core.time;
-import std.algorithm.iteration;
-import std.algorithm.mutation;
-import std.typecons;
-
-static if (UseEpoll)
-{
-    import tanya.event.internal.epoll;
-}
-
-@nogc:
-
-/**
- * Events.
- */
-enum Event : uint
-{
-	none   = 0x00, /// No events.
-	read   = 0x01, /// Non-blocking read call.
-	write  = 0x02, /// Non-blocking write call.
-	accept = 0x04, /// Connection made.
-}
-
-alias EventMask = BitFlags!Event;
-
-/**
- * Event loop.
- */
-abstract class Loop
-{
-@nogc:
-	/// Pending watchers.
-	protected Queue!Watcher pendings;
-
-	protected Queue!Watcher swapPendings;
-
-	/// Pending connections.
-	protected Vector!ConnectionWatcher connections;
-
-	/**
-	 * Initializes the loop.
-	 */
-	this()
-	{
-		connections = make!(Vector!ConnectionWatcher)(defaultAllocator);
-		pendings = make!(Queue!Watcher)(defaultAllocator);
-		swapPendings = make!(Queue!Watcher)(defaultAllocator);
-	}
-
-	/**
-	 * Frees loop internals.
-	 */
-	~this()
-	{
-		finalize(defaultAllocator, connections);
-		finalize(defaultAllocator, pendings);
-		finalize(defaultAllocator, swapPendings);
-	}
-
-	/**
-	 * Starts the loop.
-	 */
-    void run()
-    {
-		done_ = false;
-		do
-		{
-			poll();
-
-			// Invoke pendings
-			swapPendings.each!((ref p) => p.invoke());
-
-			swap(pendings, swapPendings);
-		}
-		while (!done_);
-    }
-
-	/**
-	 * Break out of the loop.
-	 */
-    void unloop() @safe pure nothrow
-    {
-		done_ = true;
-    }
-
-	/**
-	 * Start watching.
-	 *
-	 * Params:
-	 * 	watcher = Watcher.
-	 */
-	void start(ConnectionWatcher watcher)
-	{
-		if (watcher.active)
-		{
-			return;
-		}
-		watcher.active = true;
-		watcher.accept = &acceptConnection;
-		connections[watcher.socket] = watcher;
-
-		modify(watcher.socket, EventMask(Event.none), EventMask(Event.accept));
-	}
-
-	/**
-	 * Stop watching.
-	 *
-	 * Params:
-	 * 	watcher = Watcher.
-	 */
-	void stop(ConnectionWatcher watcher)
-	{
-		if (!watcher.active)
-		{
-			return;
-		}
-		watcher.active = false;
-
-		modify(watcher.socket, EventMask(Event.accept), EventMask(Event.none));
-	}
-
-	/**
-	 * Feeds the given event set into the event loop, as if the specified event
-	 * had happened for the specified watcher.
-	 *
-	 * Params:
-	 * 	transport = Affected transport.
-	 */
-	void feed(DuplexTransport transport)
-	{
-		pendings.insertBack(connections[transport.socket]);
-	}
-
-	/**
-	 * Should be called if the backend configuration changes.
-	 *
-	 * Params:
-	 * 	socket    = Socket.
-	 * 	oldEvents = The events were already set.
-	 * 	events    = The events should be set.
-	 *
-	 * Returns: $(D_KEYWORD true) if the operation was successful.
-	 */
-	protected bool modify(int socket, EventMask oldEvents, EventMask events);
-
-	/**
-	 * Returns: The blocking time.
-	 */
-	protected @property inout(Duration) blockTime()
-	inout @safe pure nothrow
-	{
-		// Don't block if we have to do.
-		return swapPendings.empty ? blockTime_ : Duration.zero;
-	}
-
-	/**
-	 * Sets the blocking time for IO watchers.
-	 *
-	 * Params:
-	 * 	blockTime = The blocking time. Cannot be larger than
-	 * 	            $(D_PSYMBOL maxBlockTime).
-	 */
-	protected @property void blockTime(in Duration blockTime) @safe pure nothrow
-	in
-	{
-		assert(blockTime <= 1.dur!"hours", "Too long to wait.");
-		assert(!blockTime.isNegative);
-	}
-	body
-	{
-		blockTime_ = blockTime;
-	}
-
-	/**
-	 * Does the actual polling.
-	 */
-	protected void poll();
-
-	/**
-	 * Accept incoming connections.
-	 *
-	 * Params:
-	 * 	protocolFactory = Protocol factory.
-	 * 	socket          = Socket.
-	 */
-	protected void acceptConnection(Protocol delegate() @nogc protocolFactory,
-	                                int socket);
-
-	/// Whether the event loop should be stopped.
-    private bool done_;
-
-	/// Maximal block time.
-	protected Duration blockTime_ = 1.dur!"minutes";
-}
-
-/**
- * Exception thrown on errors in the event loop.
- */
-class BadLoopException : Exception
-{
-@nogc:
-	/**
-	 * Params:
-	 * 	file = The file where the exception occurred.
-	 * 	line = The line number where the exception occurred.
-	 * 	next = The previous exception in the chain of exceptions, if any.
-	 */
-	this(string file = __FILE__, size_t line = __LINE__, Throwable next = null)
-	pure @safe nothrow const
-	{
-		super("Event loop cannot be initialized.", file, line, next);
-	}
-}
-
-/**
- * Returns the event loop used by default. If an event loop wasn't set with
- * $(D_PSYMBOL defaultLoop) before, $(D_PSYMBOL getDefaultLoop()) will try to
- * choose an event loop supported on the system.
- *
- * Returns: The default event loop.
- */
-Loop getDefaultLoop()
-{
-    if (_defaultLoop !is null)
-    {
-		return _defaultLoop;
-	}
-
-	static if (UseEpoll)
-	{
-		_defaultLoop = make!EpollLoop(defaultAllocator);
-	}
-
-    return _defaultLoop;
-}
-
-/**
- * Sets the default event loop.
- *
- * This property makes it possible to implement your own backends or event
- * loops, for example, if the system is not supported or if you want to
- * extend the supported implementation. Just extend $(D_PSYMBOL Loop) and pass
- * your implementation to this property.
- *
- * Params:
- * 	loop = The event loop.
- */
-@property void defaultLoop(Loop loop)
-in
-{
-	assert(loop !is null);
-}
-body
-{
-	_defaultLoop = loop;
-}
-
-private Loop _defaultLoop;

source/tanya/event/protocol.d

@@ -1,46 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.protocol;
-
-import tanya.event.transport;
-
-/**
- * Common protocol interface.
- */
-interface Protocol
-{
-@nogc:
-	/**
-	 * Params:
-	 * 	data = Read data.
-	 */
-	void received(ubyte[] data);
-
-	/**
-	 * Called when a connection is made.
-	 *
-	 * Params:
-	 * 	transport = Protocol transport.
-	 */
-	void connected(DuplexTransport transport);
-
-	/**
-	 * Called when a connection is lost.
-	 */
-	void disconnected();
-}
-
-/**
- * Interface for TCP.
- */
-interface TransmissionControlProtocol  : Protocol
-{
-}

source/tanya/event/transport.d

@@ -1,138 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.transport;
-
-import tanya.container.buffer;
-import tanya.event.protocol;
-
-/**
- * Exception thrown on read/write errors.
- */
-class TransportException : Exception
-{
-@nogc:
-	/**
-	 * Params:
-	 * 	msg  = Message to output.
-	 * 	file = The file where the exception occurred.
-	 * 	line = The line number where the exception occurred.
-	 * 	next = The previous exception in the chain of exceptions, if any.
-	 */
-	this(string msg,
-	     string file = __FILE__,
-	     size_t line = __LINE__,
-	     Throwable next = null) pure @safe nothrow const
-	{
-		super(msg, file, line, next);
-	}
-}
-
-/**
- * Base transport interface.
- */
-interface Transport
-{
-@nogc:
-	/**
-	 * Returns: Protocol.
-	 */
-	@property Protocol protocol() @safe pure nothrow;
-
-	/**
-	 * Returns: $(D_KEYWORD true) if the peer closed the connection,
-	 *          $(D_KEYWORD false) otherwise.
-	 */
-	@property immutable(bool) disconnected() const @safe pure nothrow;
-
-	/**
-	 * Params:
-	 * 	protocol = Application protocol.
-	 */
-	@property void protocol(Protocol protocol) @safe pure nothrow
-	in
-	{
-		assert(protocol !is null, "protocolConnected cannot be unset.");
-	}
-
-	/**
-	 * Returns: Application protocol.
-	 */
-	@property inout(Protocol) protocol() inout @safe pure nothrow;
-
-	/**
-	 * Returns: Transport socket.
-	 */
-	int socket() const @safe pure nothrow;
-}
-
-/**
- * Interface for read-only transports.
- */
-interface ReadTransport : Transport
-{
-@nogc:
-	/**
-	 * Returns: Underlying output buffer.
-	 */
-	@property ReadBuffer output();
-
-	/**
-	 * Reads data into the buffer.
-	 *
-	 * Returns: Whether the reading is completed.
-	 *
-	 * Throws: $(D_PSYMBOL TransportException) if a read error is occured.
-	 */
-	bool receive()
-	in
-	{
-		assert(!disconnected);
-	}
-}
-
-/**
- * Interface for write-only transports.
- */
-interface WriteTransport : Transport
-{
-@nogc:
-	/**
-	 * Returns: Underlying input buffer.
-	 */
-	@property WriteBuffer input();
-
-	/**
-	 * Write some data to the transport.
-	 *
-	 * Params:
-	 * 	data = Data to send.
-	 */
-	void write(ubyte[] data);
-
-	/**
-	 * Returns: Whether the writing is completed.
-	 *
-	 * Throws: $(D_PSYMBOL TransportException) if a read error is occured.
-	 */
-	bool send()
-	in
-	{
-		assert(input.length);
-		assert(!disconnected);
-	}
-}
-
-/**
- * Represents a bidirectional transport.
- */
-abstract class DuplexTransport : ReadTransport, WriteTransport
-{
-}

source/tanya/event/watcher.d

@@ -1,210 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.event.watcher;
-
-import tanya.event.protocol;
-import tanya.event.transport;
-import tanya.memory;
-import std.functional;
-
-/**
- * A watcher is an opaque structure that you allocate and register to record
- * your interest in some event. 
- */
-abstract class Watcher
-{
-@nogc:
-    /// Whether the watcher is active.
-    bool active;
-
-	/**
-	 * Invoke some action on event.
-	 */
-	void invoke();
-}
-
-class ConnectionWatcher : Watcher
-{
-@nogc:
-	/// Watched file descriptor.
-    private int socket_;
-
-	/// Protocol factory.
-	protected Protocol delegate() protocolFactory;
-
-	/// Callback.
-	package void delegate(Protocol delegate() @nogc protocolFactory,
-	                      int socket) accept;
-
-	invariant
-	{
-		assert(socket_ >= 0, "Called with negative file descriptor.");
-	}
-
-	/**
-	 * Params:
-	 * 	protocolFactory = Function returning a new $(D_PSYMBOL Protocol) instance.
-	 * 	socket          = Socket.
-	 */
-	this(Protocol function() @nogc protocolFactory, int socket)
-	{
-		this.protocolFactory = toDelegate(protocolFactory);
-		socket_ = socket;
-	}
-
-	/// Ditto.
-	this(Protocol delegate() @nogc protocolFactory, int socket)
-	{
-		this.protocolFactory = protocolFactory;
-		socket_ = socket;
-	}
-
-	/// Ditto.
-	protected this(Protocol function() @nogc protocolFactory)
-	{
-		this.protocolFactory = toDelegate(protocolFactory);
-	}
-
-	/// Ditto.
-	protected this(Protocol delegate() @nogc protocolFactory)
-	{
-		this.protocolFactory = protocolFactory;
-	}
-
-	/**
-	 * Returns: Socket.
-	 */
-	@property inout(int) socket() inout @safe pure nothrow
-	{
-		return socket_;
-	}
-
-	/**
-	 * Returns: Application protocol factory.
-	 */
-	@property inout(Protocol delegate() @nogc) protocol() inout
-	{
-		return protocolFactory;
-	}
-
-	override void invoke()
-	{
-		accept(protocol, socket);
-	}
-}
-
-/**
- * Contains a pending watcher with the invoked events or a transport can be
- * read from.
- */
-class IOWatcher : ConnectionWatcher
-{
-@nogc:
-	/// References a watcher or a transport.
-	DuplexTransport transport_;
-
-	/**
-	 * Params:
-	 * 	protocolFactory = Function returning application specific protocol.
-	 * 	transport       = Transport.
-	 */
-	this(Protocol delegate() @nogc protocolFactory,
-		 DuplexTransport transport)
-	in
-	{
-		assert(transport !is null);
-		assert(protocolFactory !is null);
-	}
-	body
-	{
-		super(protocolFactory);
-		this.transport_ = transport;
-	}
-
-	~this()
-	{
-		finalize(defaultAllocator, transport_);
-	}
-
-    /**
-     * Assigns a transport.
-     *
-     * Params:
-	 * 	protocolFactory = Function returning application specific protocol.
-	 * 	transport       = Transport.
-     *
-	 * Returns: $(D_KEYWORD this).
-     */
-	IOWatcher opCall(Protocol delegate() @nogc protocolFactory,
-	                 DuplexTransport transport) @safe pure nothrow
-	in
-	{
-		assert(transport !is null);
-		assert(protocolFactory !is null);
-	}
-	body
-	{
-		this.protocolFactory = protocolFactory;
-        this.transport_ = transport;
-		return this;
-	}
-
-	/**
-	 * Returns: Transport used by this watcher.
-	 */
-	@property inout(DuplexTransport) transport() inout @safe pure nothrow
-	{
-		return transport_;
-	}
-
-	/**
-	 * Returns: Socket.
-	 */
-	override @property inout(int) socket() inout @safe pure nothrow
-	{
-		return transport.socket;
-	}
-
-	/**
-	 * Invokes the watcher callback.
-	 *
-	 * Finalizes the transport on disconnect.
-	 */
-	override void invoke()
-	{
-		if (transport.protocol is null)
-		{
-			transport.protocol = protocolFactory();
-			transport.protocol.connected(transport);
-		}
-		else if (transport.disconnected)
-		{
-			transport.protocol.disconnected();
-			finalize(defaultAllocator, transport_);
-			protocolFactory = null;
-		}
-		else if (transport.output.length)
-		{
-			transport.protocol.received(transport.output[]);
-		}
-		else if (transport.input.length)
-		{
-			try
-			{
-				transport.send();
-			}
-			catch (TransportException e)
-			{
-				finalize(defaultAllocator, e);
-			}
-		}
-	}
-}

source/tanya/format/conv.d

@@ -0,0 +1,537 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module provides functions for converting between different types.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.format.conv;
+
+import std.traits;
+import tanya.memory;
+
+/**
+ * Thrown if a type conversion fails.
+ */
+final class ConvException : Exception
+{
+    /**
+     * Params:
+     *  msg  = The message for the exception.
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string msg,
+         string file = __FILE__,
+         size_t line = __LINE__,
+         Throwable next = null) @nogc @safe pure nothrow
+    {
+        super(msg, file, line, next);
+    }
+}
+
+/**
+ * If the source type $(D_PARAM From) and the target type $(D_PARAM To) are
+ * equal, does nothing. If $(D_PARAM From) can be implicitly converted to
+ * $(D_PARAM To), just returns $(D_PARAM from).
+ *
+ * Params:
+ *  To = Target type.
+ *
+ * Returns: $(D_PARAM from).
+ */
+template to(To)
+{
+    /**
+     * Params:
+     *  From = Source type.
+     *  from = Source value.
+     */
+    ref To to(From)(ref From from)
+    if (is(To == From))
+    {
+        return from;
+    }
+
+    /// Ditto.
+    To to(From)(From from)
+    if (is(Unqual!To == Unqual!From) || (isNumeric!From && isFloatingPoint!To))
+    {
+        return from;
+    }
+}
+
+///
+pure nothrow @safe @nogc unittest
+{
+    auto val = 5.to!int();
+    assert(val == 5);
+    static assert(is(typeof(val) == int));
+}
+
+private pure nothrow @safe @nogc unittest
+{
+    int val = 5;
+    assert(val.to!int() == 5);
+}
+
+/**
+ * Performs checked conversion from an integral type $(D_PARAM From) to an
+ * integral type $(D_PARAM To).
+ *
+ * Params:
+ *  From = Source type.
+ *  To   = Target type.
+ *  from = Source value.
+ *
+ * Returns: $(D_PARAM from) converted to $(D_PARAM To).
+ *
+ * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is too small or too
+ *         large to be represented by $(D_PARAM To).
+ */
+To to(To, From)(From from)
+if (isIntegral!From
+ && isIntegral!To
+ && !is(Unqual!To == Unqual!From)
+ && !is(To == enum))
+{
+    static if ((isUnsigned!From && isSigned!To && From.sizeof == To.sizeof)
+            || From.sizeof > To.sizeof)
+    {
+        if (from > To.max)
+        {
+            throw make!ConvException(defaultAllocator,
+                                     "Positive integer overflow");
+        }
+    }
+    static if (isSigned!From)
+    {
+        static if (isUnsigned!To)
+        {
+            if (from < 0)
+            {
+                throw make!ConvException(defaultAllocator,
+                                         "Negative integer overflow");
+            }
+        }
+        else static if (From.sizeof > To.sizeof)
+        {
+            if (from < To.min)
+            {
+                throw make!ConvException(defaultAllocator,
+                                         "Negative integer overflow");
+            }
+        }
+    }
+    static if (From.sizeof <= To.sizeof)
+    {
+        return from;
+    }
+    else static if (isSigned!To)
+    {
+        return cast(To) from;
+    }
+    else
+    {
+        return from & To.max;
+    }
+}
+
+private pure nothrow @safe @nogc unittest
+{
+    // ubyte -> ushort
+    assert((cast(ubyte) 0).to!ushort == 0);
+    assert((cast(ubyte) 1).to!ushort == 1);
+    assert((cast(ubyte) (ubyte.max - 1)).to!ushort == ubyte.max - 1);
+    assert((cast(ubyte) ubyte.max).to!ushort == ubyte.max);
+
+    // ubyte -> short
+    assert((cast(ubyte) 0).to!short == 0);
+    assert((cast(ubyte) 1).to!short == 1);
+    assert((cast(ubyte) (ubyte.max - 1)).to!short == ubyte.max - 1);
+    assert((cast(ubyte) ubyte.max).to!short == ubyte.max);
+}
+
+private unittest
+{
+    // ubyte <- ushort
+    assert((cast(ushort) 0).to!ubyte == 0);
+    assert((cast(ushort) 1).to!ubyte == 1);
+    assert((cast(ushort) (ubyte.max - 1)).to!ubyte == ubyte.max - 1);
+    assert((cast(ushort) ubyte.max).to!ubyte == ubyte.max);
+
+    // ubyte <- short
+    assert((cast(short) 0).to!ubyte == 0);
+    assert((cast(short) 1).to!ubyte == 1);
+    assert((cast(short) (ubyte.max - 1)).to!ubyte == ubyte.max - 1);
+    assert((cast(short) ubyte.max).to!ubyte == ubyte.max);
+
+    // short <-> int
+    assert(short.min.to!int == short.min);
+    assert((short.min + 1).to!int == short.min + 1);
+    assert((cast(short) -1).to!int == -1);
+    assert((cast(short) 0).to!int == 0);
+    assert((cast(short) 1).to!int == 1);
+    assert((short.max - 1).to!int == short.max - 1);
+    assert(short.max.to!int == short.max);
+
+    assert((cast(int) short.min).to!short == short.min);
+    assert((cast(int) short.min + 1).to!short == short.min + 1);
+    assert((cast(int) -1).to!short == -1);
+    assert((cast(int) 0).to!short == 0);
+    assert((cast(int) 1).to!short == 1);
+    assert((cast(int) short.max - 1).to!short == short.max - 1);
+    assert((cast(int) short.max).to!short == short.max);
+
+    // uint <-> int
+    assert((cast(uint) 0).to!int == 0);
+    assert((cast(uint) 1).to!int == 1);
+    assert((cast(uint) (int.max - 1)).to!int == int.max - 1);
+    assert((cast(uint) int.max).to!int == int.max);
+
+    assert((cast(int) 0).to!uint == 0);
+    assert((cast(int) 1).to!uint == 1);
+    assert((cast(int) (int.max - 1)).to!uint == int.max - 1);
+    assert((cast(int) int.max).to!uint == int.max);
+}
+
+private unittest
+{
+    ConvException exception;
+    try
+    {
+        assert(int.min.to!short == int.min);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private unittest
+{
+    ConvException exception;
+    try
+    {
+        assert(int.max.to!short == int.max);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private unittest
+{
+    ConvException exception;
+    try
+    {
+        assert(uint.max.to!ushort == ushort.max);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private unittest
+{
+    ConvException exception;
+    try
+    {
+        assert((-1).to!uint == -1);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    enum Test : int
+    {
+        one,
+        two,
+    }
+    assert(Test.one.to!int == 0);
+    assert(Test.two.to!int == 1);
+}
+
+/**
+ * Converts a number to a boolean.
+ *
+ * Params:
+ *  From = Source type.
+ *  To   = Target type.
+ *  from = Source value.
+ *
+ * Returns: $(D_KEYWORD true) if $(D_INLINECODE from > 0 && from <= 1),
+ *          otherwise $(D_KEYWORD false).
+ *
+ * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is greater than `1` or
+ *         less than `0`.
+ */
+To to(To, From)(From from)
+if (isNumeric!From && is(Unqual!To == bool) && !is(Unqual!To == Unqual!From))
+{
+    if (from == 0)
+    {
+        return false;
+    }
+    else if (from < 0)
+    {
+        throw make!ConvException(defaultAllocator,
+                                 "Negative number overflow");
+    }
+    else if (from <= 1)
+    {
+        return true;
+    }
+    throw make!ConvException(defaultAllocator,
+                             "Positive number overflow");
+}
+
+private @nogc unittest
+{
+    assert(0.0.to!bool == false);
+    assert(0.2.to!bool == true);
+    assert(0.5.to!bool == true);
+    assert(1.0.to!bool == true);
+
+    assert(0.to!bool == false);
+    assert(1.to!bool == true);
+}
+
+private @nogc unittest
+{
+    ConvException exception;
+    try
+    {
+        assert((-1).to!bool == true);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    ConvException exception;
+    try
+    {
+        assert(2.to!bool == true);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+/**
+ * Converts a boolean to a number. $(D_KEYWORD true) is `1`, $(D_KEYWORD false)
+ * is `0`.
+ *
+ * Params:
+ *  From = Source type.
+ *  To   = Target type.
+ *  from = Source value.
+ *
+ * Returns: `1` if $(D_PARAM from) is $(D_KEYWORD true), otherwise `0`.
+ */
+To to(To, From)(From from)
+if (is(Unqual!From == bool) && isNumeric!To && !is(Unqual!To == Unqual!From))
+{
+    return from;
+}
+
+///
+pure nothrow @safe @nogc unittest
+{
+    assert(true.to!float == 1.0);
+    assert(true.to!double == 1.0);
+    assert(true.to!ubyte == 1);
+    assert(true.to!byte == 1);
+    assert(true.to!ushort == 1);
+    assert(true.to!short == 1);
+    assert(true.to!uint == 1);
+    assert(true.to!int == 1);
+
+    assert(false.to!float == 0);
+    assert(false.to!double == 0);
+    assert(false.to!ubyte == 0);
+    assert(false.to!byte == 0);
+    assert(false.to!ushort == 0);
+    assert(false.to!short == 0);
+    assert(false.to!uint == 0);
+    assert(false.to!int == 0);
+}
+
+/**
+ * Converts a floating point number to an integral type.
+ *
+ * Params:
+ *  From = Source type.
+ *  To   = Target type.
+ *  from = Source value.
+ *
+ * Returns: Truncated $(D_PARAM from) (everything after the decimal point is
+ *          dropped).
+ *
+ * Throws: $(D_PSYMBOL ConvException) if
+ *         $(D_INLINECODE from < To.min || from > To.max).
+ */
+To to(To, From)(From from)
+if (isFloatingPoint!From
+ && isIntegral!To
+ && !is(Unqual!To == Unqual!From)
+ && !is(To == enum))
+{
+    if (from > To.max)
+    {
+        throw make!ConvException(defaultAllocator,
+                                 "Positive number overflow");
+    }
+    else if (from < To.min)
+    {
+        throw make!ConvException(defaultAllocator,
+                                 "Negative number overflow");
+    }
+    return cast(To) from;
+}
+
+///
+@nogc unittest
+{
+    assert(1.5.to!int == 1);
+    assert(2147483646.5.to!int == 2147483646);
+    assert((-2147483647.5).to!int == -2147483647);
+    assert(2147483646.5.to!uint == 2147483646);
+}
+
+private @nogc unittest
+{
+    ConvException exception;
+    try
+    {
+        assert(2147483647.5.to!int == 2147483647);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    ConvException exception;
+    try
+    {
+        assert((-2147483648.5).to!int == -2147483648);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    ConvException exception;
+    try
+    {
+        assert((-21474.5).to!uint == -21474);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+/**
+ * Performs checked conversion from an integral type $(D_PARAM From) to an
+ * $(D_KEYWORD enum).
+ *
+ * Params:
+ *  From = Source type.
+ *  To   = Target type.
+ *  from = Source value.
+ *
+ * Returns: $(D_KEYWORD enum) value.
+ *
+ * Throws: $(D_PSYMBOL ConvException) if $(D_PARAM from) is not a member of
+ *         $(D_PSYMBOL To).
+
+ */
+To to(To, From)(From from)
+if (isIntegral!From && is(To == enum))
+{
+    foreach (m; EnumMembers!To)
+    {
+        if (from == m)
+        {
+            return m;
+        }
+    }
+    throw make!ConvException(defaultAllocator,
+                             "Value not found in enum '" ~ To.stringof ~ "'");
+}
+
+///
+@nogc unittest
+{
+    enum Test : int
+    {
+        one,
+        two,
+    }
+    static assert(is(typeof(1.to!Test) == Test));
+    assert(0.to!Test == Test.one);
+    assert(1.to!Test == Test.two);
+}
+
+private @nogc unittest
+{
+    enum Test : uint
+    {
+        one,
+        two,
+    }
+
+    ConvException exception;
+    try
+    {
+        assert(5.to!Test == Test.one);
+    }
+    catch (ConvException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}

source/tanya/format/package.d

@@ -3,24 +3,13 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * This package contains formatting and conversion functions.
+ *
+ * Copyright: Eugene Wissner 2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
-module tanya.event.config;
+module tanya.format;
 
-package version (DisableBackends)
+public import tanya.format.conv;
-{
-}
-else
-{
-	version (linux)
-	{
-		enum UseEpoll = true;
-	}
-	else
-	{
-		enum UseEpoll = false;
-	}
-}

source/tanya/math.d

@@ -1,112 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.container.math;
-
-version (unittest)
-{
-	import std.algorithm.iteration;
-}
-
-@nogc:
-
-/**
- * Computes $(D_PARAM x) to the power $(D_PARAM y) modulo $(D_PARAM z).
- *
- * Params:
- * 	x = Base.
- * 	y = Exponent.
- * 	z = Divisor.
- *
- * Returns: Reminder of the division of $(D_PARAM x) to the power $(D_PARAM y)
- *          by $(D_PARAM z).
- */
-ulong pow(ulong x, ulong y, ulong z) @safe nothrow pure
-in
-{
-	assert(z > 0);
-}
-out (result)
-{
-	assert(result >= 0);
-}
-body
-{
-    ulong mask = ulong.max / 2 + 1, result;
-
-	if (y == 0)
-	{
-		return 1 % z;
-	}
-	else if (y == 1)
-	{
-		return x % z;
-	}
-    do
-    {
-        auto bit = y & mask;
-        if (!result && bit)
-        {
-            result = x;
-            continue;
-        }
-
-        result *= result;
-        if (bit)
-        {
-            result *= x;
-        }
-        result %= z;
-
-    }
-    while (mask >>= 1);
-
-	return result;
-}
-
-///
-unittest
-{
-    assert(pow(3, 5, 7) == 5);
-    assert(pow(2, 2, 1) == 0);
-    assert(pow(3, 3, 3) == 0);
-    assert(pow(7, 4, 2) == 1);
-    assert(pow(53, 0, 2) == 1);
-    assert(pow(53, 1, 3) == 2);
-    assert(pow(53, 2, 5) == 4);
-    assert(pow(0, 0, 5) == 1);
-    assert(pow(0, 5, 5) == 0);
-}
-
-/**
- * Checks if $(D_PARAM x) is a prime.
- *
- * Params:
- * 	x = The number should be checked.
- *
- * Returns: $(D_KEYWORD true) if $(D_PARAM x) is a prime number,
- *          $(D_KEYWORD false) otherwise.
- */
-bool isPseudoprime(ulong x) @safe nothrow pure
-{
-	return pow(2, x - 1, x) == 1;
-}
-
-///
-unittest
-{
-	uint[30] known = [74623, 74653, 74687, 74699, 74707, 74713, 74717, 74719,
-                      74843, 74747, 74759, 74761, 74771, 74779, 74797, 74821,
-	                  74827, 9973, 104729, 15485867, 49979693, 104395303,
-	                  593441861, 104729, 15485867, 49979693, 104395303,
-	                  593441861, 899809363, 982451653];
-
-	known.each!((ref x) => assert(isPseudoprime(x)));
-}

source/tanya/math/package.d

@@ -0,0 +1,203 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This package provides mathematical functions.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.math;
+
+import std.traits;
+public import tanya.math.mp;
+public import tanya.math.random;
+
+version (unittest)
+{
+    import std.algorithm.iteration;
+}
+
+/**
+ * Computes $(D_PARAM x) to the power $(D_PARAM y) modulo $(D_PARAM z).
+ *
+ * If $(D_PARAM I) is an $(D_PSYMBOL Integer), the allocator of $(D_PARAM x)
+ * is used to allocate the result.
+ *
+ * Params:
+ *  I = Base type.
+ *  G = Exponent type.
+ *  H = Divisor type:
+ *  x = Base.
+ *  y = Exponent.
+ *  z = Divisor.
+ *
+ * Returns: Reminder of the division of $(D_PARAM x) to the power $(D_PARAM y)
+ *          by $(D_PARAM z).
+ *
+ * Precondition: $(D_INLINECODE z > 0)
+ */
+H pow(I, G, H)(in auto ref I x, in auto ref G y, in auto ref H z)
+    if (isIntegral!I && isIntegral!G && isIntegral!H)
+in
+{
+    assert(z > 0, "Division by zero.");
+}
+body
+{
+    G mask = G.max / 2 + 1;
+    H result;
+
+    if (y == 0)
+    {
+        return 1 % z;
+    }
+    else if (y == 1)
+    {
+        return x % z;
+    }
+    do
+    {
+        immutable bit = y & mask;
+        if (!result && bit)
+        {
+            result = x;
+            continue;
+        }
+
+        result *= result;
+        if (bit)
+        {
+            result *= x;
+        }
+        result %= z;
+    }
+    while (mask >>= 1);
+
+    return result;
+}
+
+/// Ditto.
+I pow(I)(const auto ref I x, const auto ref I y, const auto ref I z)
+    if (is(I == Integer))
+in
+{
+    assert(z.length > 0, "Division by zero.");
+}
+body
+{
+    size_t i;
+    auto tmp1 = Integer(x, x.allocator);
+    auto result = Integer(x.allocator);
+    bool firstBit;
+
+    if (x.size == 0 && y.size != 0)
+    {
+        i = y.size;
+    }
+    else
+    {
+        result = 1;
+    }
+    while (i < y.size)
+    {
+        for (uint mask = 0x01; mask != 0x10000000; mask <<= 1)
+        {
+            if (y.rep[i] & mask)
+            {
+                result *= tmp1;
+                result %= z;
+            }
+            auto tmp2 = tmp1;
+            tmp1 *= tmp2;
+            tmp1 %= z;
+        }
+        ++i;
+    }
+    return result;
+}
+
+///
+pure nothrow @safe @nogc unittest
+{
+    assert(pow(3, 5, 7) == 5);
+    assert(pow(2, 2, 1) == 0);
+    assert(pow(3, 3, 3) == 0);
+    assert(pow(7, 4, 2) == 1);
+    assert(pow(53, 0, 2) == 1);
+    assert(pow(53, 1, 3) == 2);
+    assert(pow(53, 2, 5) == 4);
+    assert(pow(0, 0, 5) == 1);
+    assert(pow(0, 5, 5) == 0);
+}
+
+///
+unittest
+{
+    assert(pow(Integer(3), Integer(5), Integer(7)) == 5);
+    assert(pow(Integer(2), Integer(2), Integer(1)) == 0);
+    assert(pow(Integer(3), Integer(3), Integer(3)) == 0);
+    assert(pow(Integer(7), Integer(4), Integer(2)) == 1);
+    assert(pow(Integer(53), Integer(0), Integer(2)) == 1);
+    assert(pow(Integer(53), Integer(1), Integer(3)) == 2);
+    assert(pow(Integer(53), Integer(2), Integer(5)) == 4);
+    assert(pow(Integer(0), Integer(0), Integer(5)) == 1);
+    assert(pow(Integer(0), Integer(5), Integer(5)) == 0);
+}
+
+/**
+ * Checks if $(D_PARAM x) is a prime.
+ *
+ * Params:
+ *  x = The number should be checked.
+ *
+ * Returns: $(D_KEYWORD true) if $(D_PARAM x) is a prime number,
+ *          $(D_KEYWORD false) otherwise.
+ */
+bool isPseudoprime(ulong x) nothrow pure @safe @nogc
+{
+    return pow(2, x - 1, x) == 1;
+}
+
+///
+unittest
+{
+    uint[30] known = [74623, 74653, 74687, 74699, 74707, 74713, 74717, 74719,
+                      74843, 74747, 74759, 74761, 74771, 74779, 74797, 74821,
+                      74827, 9973, 104729, 15485867, 49979693, 104395303,
+                      593441861, 104729, 15485867, 49979693, 104395303,
+                      593441861, 899809363, 982451653];
+
+    known.each!((ref x) => assert(isPseudoprime(x)));
+}
+
+/**
+ * Params:
+ *  I = Value type.
+ *  x = Value.
+ *
+ * Returns: The absolute value of a number.
+ */
+I abs(I : Integer)(const auto ref I x)
+{
+    auto result = Integer(x, x.allocator);
+    result.sign = Sign.positive;
+    return result;
+}
+
+/// Ditto.
+I abs(I : Integer)(I x)
+{
+    x.sign = Sign.positive;
+    return x;
+}
+
+/// Ditto.
+I abs(I)(const I x)
+    if (isIntegral!I)
+{
+    return x >= 0 ? x : -x;
+}

source/tanya/math/random.d

@@ -0,0 +1,333 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Random number generator.
+ *
+ * Copyright: Eugene Wissner 2016.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.math.random;
+
+import std.digest.sha;
+import std.typecons;
+import tanya.memory;
+
+/// Block size of entropy accumulator (SHA-512).
+enum blockSize = 64;
+
+/// Maximum amount gathered from the entropy sources.
+enum maxGather = 128;
+
+/**
+ * Exception thrown if random number generating fails.
+ */
+class EntropyException : Exception
+{
+    /**
+     * Params:
+     *  msg  = Message to output.
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string msg,
+         string file = __FILE__,
+         size_t line = __LINE__,
+         Throwable next = null) pure @safe nothrow const @nogc
+    {
+        super(msg, file, line, next);
+    }
+}
+
+/**
+ * Interface for implementing entropy sources.
+ */
+abstract class EntropySource
+{
+    /// Amount of already generated entropy.
+    protected ushort size_;
+
+    /**
+     * Returns: Minimum bytes required from the entropy source.
+     */
+    @property ubyte threshold() const pure nothrow @safe @nogc;
+
+    /**
+     * Returns: Whether this entropy source is strong.
+     */
+    @property bool strong() const pure nothrow @safe @nogc;
+
+    /**
+     * Returns: Amount of already generated entropy.
+     */
+    @property ushort size() const pure nothrow @safe @nogc
+    {
+        return size_;
+    }
+
+    /**
+     * Params:
+     *  size = Amount of already generated entropy. Cannot be smaller than the
+     *         already set value.
+     */
+    @property void size(ushort size) pure nothrow @safe @nogc
+    {
+        size_ = size;
+    }
+
+    /**
+     * Poll the entropy source.
+     *
+     * Params:
+     *  output = Buffer to save the generate random sequence (the method will
+     *           to fill the buffer).
+     *
+     * Returns: Number of bytes that were copied to the $(D_PARAM output)
+     *          or $(D_PSYMBOL Nullable!ubyte.init) on error.
+     */
+    Nullable!ubyte poll(out ubyte[maxGather] output) @nogc;
+}
+
+version (linux)
+{
+    extern (C) long syscall(long number, ...) nothrow @system @nogc;
+
+    /**
+     * Uses getrandom system call.
+     */
+    class PlatformEntropySource : EntropySource
+    {
+        /**
+         * Returns: Minimum bytes required from the entropy source.
+         */
+        override @property ubyte threshold() const pure nothrow @safe @nogc
+        {
+            return 32;
+        }
+
+        /**
+         * Returns: Whether this entropy source is strong.
+         */
+        override @property bool strong() const pure nothrow @safe @nogc
+        {
+            return true;
+        }
+
+        /**
+         * Poll the entropy source.
+         *
+         * Params:
+         *  output = Buffer to save the generate random sequence (the method will
+         *           to fill the buffer).
+         *
+         * Returns: Number of bytes that were copied to the $(D_PARAM output)
+         *          or $(D_PSYMBOL Nullable!ubyte.init) on error.
+         */
+        override Nullable!ubyte poll(out ubyte[maxGather] output) nothrow @nogc
+        out (length)
+        {
+            assert(length <= maxGather);
+        }
+        body
+        {
+            // int getrandom(void *buf, size_t buflen, unsigned int flags);
+            auto length = syscall(318, output.ptr, output.length, 0);
+            Nullable!ubyte ret;
+
+            if (length >= 0)
+            {
+                ret = cast(ubyte) length;
+            }
+            return ret;
+        }
+    }
+
+    version (X86_64)
+    {
+        private unittest
+        {
+            auto entropy = defaultAllocator.make!Entropy();
+            ubyte[blockSize] output;
+            output = entropy.random;
+
+            defaultAllocator.dispose(entropy);
+        }
+    }
+}
+
+/**
+ * Pseudorandom number generator.
+ * ---
+ * auto entropy = defaultAllocator.make!Entropy();
+ *
+ * ubyte[blockSize] output;
+ *
+ * output = entropy.random;
+ *
+ * defaultAllocator.dispose(entropy);
+ * ---
+ */
+class Entropy
+{
+    /// Entropy sources.
+    protected EntropySource[] sources;
+
+    private ubyte sourceCount_;
+
+    private shared Allocator allocator;
+
+    /// Entropy accumulator.
+    protected SHA!(maxGather * 8, 512) accumulator;
+
+    /**
+     * Params:
+     *  maxSources = Maximum amount of entropy sources can be set.
+     *  allocator  = Allocator to allocate entropy sources available on the
+     *               system.
+     */
+    this(const size_t maxSources = 20,
+         shared Allocator allocator = defaultAllocator) @nogc
+    in
+    {
+        assert(maxSources > 0 && maxSources <= ubyte.max);
+        assert(allocator !is null);
+    }
+    body
+    {
+        allocator.resize(sources, maxSources);
+
+        version (linux)
+        {
+            this ~= allocator.make!PlatformEntropySource;
+        }
+    }
+
+    /**
+     * Returns: Amount of the registered entropy sources.
+     */
+    @property ubyte sourceCount() const pure nothrow @safe @nogc
+    {
+        return sourceCount_;
+    }
+
+    /**
+     * Add an entropy source.
+     *
+     * Params:
+     *  source = Entropy source.
+     *
+     * Returns: $(D_PSYMBOL this).
+     *
+     * See_Also:
+     *  $(D_PSYMBOL EntropySource)
+     */
+    Entropy opOpAssign(string Op)(EntropySource source) pure nothrow @safe @nogc
+        if (Op == "~")
+    in
+    {
+        assert(sourceCount_ <= sources.length);
+    }
+    body
+    {
+        sources[sourceCount_++] = source;
+        return this;
+    }
+
+    /**
+     * Returns: Generated random sequence.
+     *
+     * Throws: $(D_PSYMBOL EntropyException) if no strong entropy source was
+     *         registered or it failed.
+     */
+    @property ubyte[blockSize] random() @nogc
+    in
+    {
+        assert(sourceCount_ > 0, "No entropy sources defined.");
+    }
+    body
+    {
+        bool haveStrong;
+        ushort done;
+        ubyte[blockSize] output;
+
+        do
+        {
+            ubyte[maxGather] buffer;
+
+            // Run through our entropy sources
+            for (ubyte i; i < sourceCount; ++i)
+            {
+                auto outputLength = sources[i].poll(buffer);
+
+                if (!outputLength.isNull)
+                {
+                    if (outputLength > 0)
+                    {
+                        update(i, buffer, outputLength);
+                        sources[i].size = cast(ushort) (sources[i].size + outputLength);
+                    }
+                    if (sources[i].size < sources[i].threshold)
+                    {
+                        continue;
+                    }
+                    else if (sources[i].strong)
+                    {
+                        haveStrong = true;
+                    }
+                }
+                done = 257;
+            }
+        }
+        while (++done < 256);
+
+        if (!haveStrong)
+        {
+            throw allocator.make!EntropyException("No strong entropy source defined.");
+        }
+
+        output = accumulator.finish();
+
+        // Reset accumulator and counters and recycle existing entropy
+        accumulator.start();
+
+        // Perform second SHA-512 on entropy
+        output = sha512Of(output);
+
+        for (ubyte i = 0; i < sourceCount; ++i)
+        {
+            sources[i].size = 0;
+        }
+        return output;
+    }
+
+    /**
+     * Update entropy accumulator.
+     *
+     * Params:
+     *  sourceId = Entropy source index in $(D_PSYMBOL sources).
+     *  data     = Data got from the entropy source.
+     *  length   = Length of the received data.
+     */
+    protected void update(in ubyte sourceId,
+                          ref ubyte[maxGather] data,
+                          ubyte length) pure nothrow @safe @nogc
+    {
+        ubyte[2] header;
+
+        if (length > blockSize)
+        {
+            data[0 .. 64] = sha512Of(data);
+            length = blockSize;
+        }
+
+        header[0] = sourceId;
+        header[1] = length;
+
+        accumulator.put(header);
+        accumulator.put(data[0 .. length]);
+    }
+}

source/tanya/memory/allocator.d

@@ -3,7 +3,12 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * This module contains the interface for implementing custom allocators.
+ *
+ * Allocators are classes encapsulating memory allocation strategy. This allows
+ * to decouple memory management from the algorithms and the data. 
+ *
+ * Copyright: Eugene Wissner 2016-2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
  * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
@@ -11,22 +16,24 @@
 module tanya.memory.allocator;
 
 /**
- * This interface should be similar to $(D_PSYMBOL
+ * Abstract class implementing a basic allocator.
- * std.experimental.allocator.IAllocator), but usable in
- * $(D_KEYWORD @nogc)-code.
  */
 interface Allocator
 {
-@nogc:
     /**
-	 * Allocates $(D_PARAM s) bytes of memory.
+     * Returns: Alignment offered.
+     */
+    @property uint alignment() const shared pure nothrow @safe @nogc;
+
+    /**
+     * Allocates $(D_PARAM size) bytes of memory.
      *
      * Params:
-	 * 	s = Amount of memory to allocate.
+     *  size = Amount of memory to allocate.
      *
-	 * Returns: The pointer to the new allocated memory.
+     * Returns: Pointer to the new allocated memory.
      */
-    void[] allocate(size_t s) @safe;
+    void[] allocate(const size_t size) shared pure nothrow @nogc;
 
     /**
      * Deallocates a memory block.
@@ -36,7 +43,7 @@ interface Allocator
      *
      * Returns: Whether the deallocation was successful.
      */
-    bool deallocate(void[] p) @safe;
+    bool deallocate(void[] p) shared pure nothrow @nogc;
 
     /**
      * Increases or decreases the size of a memory block.
@@ -45,14 +52,28 @@ interface Allocator
      *  p    = A pointer to the memory block.
      *  size = Size of the reallocated block.
      *
-	 * Returns: Whether the reallocation was successful.
+     * Returns: Pointer to the allocated memory.
      */
-	bool reallocate(ref void[] p, size_t s) @safe;
+    bool reallocate(ref void[] p, const size_t size) shared pure nothrow @nogc;
 
     /**
-     * Static allocator instance and initializer.
+     * Reallocates a memory block in place if possible or returns
+     * $(D_KEYWORD false). This function cannot be used to allocate or
+     * deallocate memory, so if $(D_PARAM p) is $(D_KEYWORD null) or
+     * $(D_PARAM size) is `0`, it should return $(D_KEYWORD false).
      *
-	 * Returns: An $(D_PSYMBOL Allocator) instance.
+     * Params:
+     *  p    = A pointer to the memory block.
+     *  size = Size of the reallocated block.
+     *
+     * Returns: $(D_KEYWORD true) if successful, $(D_KEYWORD false) otherwise.
      */
-	static @property Allocator instance() @safe;
+    bool reallocateInPlace(ref void[] p, const size_t size)
+    shared pure nothrow @nogc;
+}
+
+package template GetPureInstance(T : Allocator)
+{
+    alias GetPureInstance = shared(T) function()
+                            pure nothrow @nogc;
 }

source/tanya/memory/mallocator.d

@@ -0,0 +1,223 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Allocator based on $(D_PSYMBOL malloc), $(D_PSYMBOL realloc) and $(D_PSYMBOL free).
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.memory.mallocator;
+
+import core.stdc.stdlib;
+import tanya.memory.allocator;
+
+/**
+ * Wrapper for $(D_PSYMBOL malloc)/$(D_PSYMBOL realloc)/$(D_PSYMBOL free) from
+ * the C standard library.
+ */
+final class Mallocator : Allocator
+{
+    private alias MallocType = extern (C) void* function(size_t)
+                               pure nothrow @system @nogc;
+    private alias FreeType = extern (C) void function(void*)
+                             pure nothrow @system @nogc;
+    private alias ReallocType = extern (C) void* function(void*, size_t)
+                                pure nothrow @system @nogc;
+
+    /**
+     * Allocates $(D_PARAM size) bytes of memory.
+     *
+     * Params:
+     *  size = Amount of memory to allocate.
+     *
+     * Returns: The pointer to the new allocated memory.
+     */
+    void[] allocate(const size_t size) shared pure nothrow @nogc
+    {
+        if (size == 0)
+        {
+            return null;
+        }
+        auto p = (cast(MallocType) &malloc)(size + psize);
+
+        return p is null ? null : p[psize .. psize + size];
+    }
+
+    ///
+    @nogc nothrow unittest
+    {
+        auto p = Mallocator.instance.allocate(20);
+        assert(p.length == 20);
+        Mallocator.instance.deallocate(p);
+
+        p = Mallocator.instance.allocate(0);
+        assert(p.length == 0);
+    }
+
+    /**
+     * Deallocates a memory block.
+     *
+     * Params:
+     *  p = A pointer to the memory block to be freed.
+     *
+     * Returns: Whether the deallocation was successful.
+     */
+    bool deallocate(void[] p) shared pure nothrow @nogc
+    {
+        if (p !is null)
+        {
+            (cast(FreeType) &free)(p.ptr - psize);
+        }
+        return true;
+    }
+
+    ///
+    @nogc nothrow unittest
+    {
+        void[] p;
+        assert(Mallocator.instance.deallocate(p));
+
+        p = Mallocator.instance.allocate(10);
+        assert(Mallocator.instance.deallocate(p));
+    }
+
+    /**
+     * Reallocating in place isn't supported.
+     *
+     * Params:
+     *  p    = A pointer to the memory block.
+     *  size = Size of the reallocated block.
+     *
+     * Returns: $(D_KEYWORD false).
+     */
+    bool reallocateInPlace(ref void[] p, const size_t size)
+    shared pure nothrow @nogc
+    {
+        return false;
+    }
+
+    ///
+    @nogc nothrow unittest
+    {
+        void[] p;
+        assert(!Mallocator.instance.reallocateInPlace(p, 8));
+    }
+
+    /**
+     * Increases or decreases the size of a memory block.
+     *
+     * Params:
+     *  p    = A pointer to the memory block.
+     *  size = Size of the reallocated block.
+     *
+     * Returns: Whether the reallocation was successful.
+     */
+    bool reallocate(ref void[] p, const size_t size) shared pure nothrow @nogc
+    {
+        if (size == 0)
+        {
+            if (deallocate(p))
+            {
+                p = null;
+                return true;
+            }
+        }
+        else if (p is null)
+        {
+            p = allocate(size);
+            return p is null ? false : true;
+        }
+        else
+        {
+            auto r = (cast(ReallocType) &realloc)(p.ptr - psize, size + psize);
+
+            if (r !is null)
+            {
+                p = r[psize .. psize + size];
+                return true;
+            }
+        }
+        return false;
+    }
+
+    ///
+    @nogc nothrow unittest
+    {
+        void[] p;
+
+        assert(Mallocator.instance.reallocate(p, 20));
+        assert(p.length == 20);
+
+        assert(Mallocator.instance.reallocate(p, 30));
+        assert(p.length == 30);
+
+        assert(Mallocator.instance.reallocate(p, 10));
+        assert(p.length == 10);
+
+        assert(Mallocator.instance.reallocate(p, 0));
+        assert(p is null);
+    }
+
+    // Fails with false.
+    private @nogc nothrow unittest
+    {
+        void[] p = Mallocator.instance.allocate(20);
+        void[] oldP = p;
+        assert(!Mallocator.instance.reallocate(p, size_t.max - Mallocator.psize * 2));
+        assert(oldP is p);
+        Mallocator.instance.deallocate(p);
+    }
+
+    /**
+     * Returns: The alignment offered.
+     */
+    @property uint alignment() shared const pure nothrow @safe @nogc
+    {
+        return (void*).alignof;
+    }
+
+    private nothrow @nogc unittest
+    {
+        assert(Mallocator.instance.alignment == (void*).alignof);
+    }
+
+    static private shared(Mallocator) instantiate() nothrow @nogc
+    {
+        if (instance_ is null)
+        {
+            const size = __traits(classInstanceSize, Mallocator) + psize;
+            void* p = malloc(size);
+
+            if (p !is null)
+            {
+                p[psize .. size] = typeid(Mallocator).initializer[];
+                instance_ = cast(shared Mallocator) p[psize .. size].ptr;
+            }
+        }
+        return instance_;
+    }
+
+    /**
+     * Static allocator instance and initializer.
+     *
+     * Returns: The global $(D_PSYMBOL Allocator) instance.
+     */
+    static @property shared(Mallocator) instance() pure nothrow @nogc
+    {
+        return (cast(GetPureInstance!Mallocator) &instantiate)();
+    }
+
+    ///
+    @nogc nothrow unittest
+    {
+        assert(instance is instance);
+    }
+
+    private enum ushort psize = 8;
+
+    private shared static Mallocator instance_;
+}

source/tanya/memory/mmappool.d

@@ -0,0 +1,713 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Native allocator for Posix and Windows.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.memory.mmappool;
+
+import core.stdc.string;
+import std.algorithm.comparison;
+import tanya.memory.allocator;
+
+version (Posix)
+{
+    import core.sys.posix.sys.mman : PROT_READ, PROT_WRITE, MAP_PRIVATE,
+                                     MAP_ANON, MAP_FAILED;
+    import core.sys.posix.unistd;
+
+    extern (C)
+    private void* mmap(void* addr,
+                       size_t len,
+                       int prot,
+                       int flags,
+                       int fd,
+                       off_t offset) pure nothrow @system @nogc;
+
+    extern (C)
+    private int munmap(void* addr, size_t len) pure nothrow @system @nogc;
+
+    private void* mapMemory(const size_t len) pure nothrow @system @nogc
+    {
+        void* p = mmap(null,
+                       len,
+                       PROT_READ | PROT_WRITE,
+                       MAP_PRIVATE | MAP_ANON,
+                       -1,
+                       0);
+        return p is MAP_FAILED ? null : p;
+    }
+
+    private bool unmapMemory(shared void* addr, const size_t len)
+    pure nothrow @system @nogc
+    {
+        return munmap(cast(void*) addr, len) == 0;
+    }
+}
+else version (Windows)
+{
+    import core.sys.windows.winbase : GetSystemInfo, SYSTEM_INFO;
+
+    extern (Windows)
+    private void* VirtualAlloc(void*, size_t, uint, uint)
+    pure nothrow @system @nogc;
+
+    extern (Windows)
+    private int VirtualFree(void* addr, size_t len, uint)
+    pure nothrow @system @nogc;
+
+    private void* mapMemory(const size_t len) pure nothrow @system @nogc
+    {
+        return VirtualAlloc(null,
+                            len,
+                            0x00001000, // MEM_COMMIT
+                            0x04); // PAGE_READWRITE
+    }
+
+    private bool unmapMemory(shared void* addr, const size_t len)
+    pure nothrow @system @nogc
+    {
+        return VirtualFree(cast(void*) addr, 0, 0x8000) == 0;
+    }
+}
+
+/**
+ * This allocator allocates memory in regions (multiple of 64 KB for example).
+ * Each region is then splitted in blocks. So it doesn't request the memory
+ * from the operating system on each call, but only if there are no large
+ * enough free blocks in the available regions.
+ * Deallocation works in the same way. Deallocation doesn't immediately
+ * gives the memory back to the operating system, but marks the appropriate
+ * block as free and only if all blocks in the region are free, the complete
+ * region is deallocated.
+ *
+ * ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ * |      |     |         |     |            ||      |     |                  |
+ * |      |prev <-----------    |            ||      |     |                  |
+ * |  R   |  B  |         |  B  |            ||   R  |  B  |                  |
+ * |  E   |  L  |         |  L  |           next  E  |  L  |                  |
+ * |  G   |  O  |  DATA   |  O  |   FREE    --->  G  |  O  |       DATA       |
+ * |  I   |  C  |         |  C  |           <---  I  |  C  |                  |
+ * |  O   |  K  |         |  K  |           prev  O  |  K  |                  |
+ * |  N   |    -----------> next|            ||   N  |     |                  |
+ * |      |     |         |     |            ||      |     |                  |
+ * ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
+ */
+final class MmapPool : Allocator
+{
+    version (none)
+    {
+        pure nothrow @nogc invariant
+        {
+            for (auto r = &head; *r !is null; r = &((*r).next))
+            {
+                auto block = cast(Block) (cast(void*) *r + RegionEntry.sizeof);
+                do
+                {
+                    assert(block.prev is null || block.prev.next is block);
+                    assert(block.next is null || block.next.prev is block);
+                    assert(block.region is *r);
+                }
+                while ((block = block.next) !is null);
+            }
+        }
+    }
+
+    /**
+     * Allocates $(D_PARAM size) bytes of memory.
+     *
+     * Params:
+     *  size = Amount of memory to allocate.
+     *
+     * Returns: Pointer to the new allocated memory.
+     */
+    void[] allocate(const size_t size) shared pure nothrow @nogc
+    {
+        if (size == 0)
+        {
+            return null;
+        }
+        const dataSize = addAlignment(size);
+        if (dataSize < size)
+        {
+            return null;
+        }
+
+        void* data = findBlock(dataSize);
+        if (data is null)
+        {
+            data = initializeRegion(dataSize);
+        }
+
+        return data is null ? null : data[0 .. size];
+    }
+
+    ///
+    nothrow unittest
+    {
+        auto p = MmapPool.instance.allocate(20);
+        assert(p);
+        MmapPool.instance.deallocate(p);
+
+        p = MmapPool.instance.allocate(0);
+        assert(p.length == 0);
+    }
+
+    // Issue 245: https://issues.caraus.io/issues/245.
+    private @nogc unittest
+    {
+        // allocate() check.
+        size_t tooMuchMemory = size_t.max
+                             - MmapPool.alignment_
+                             - BlockEntry.sizeof * 2
+                             - RegionEntry.sizeof
+                             - MmapPool.instance.pageSize;
+        assert(MmapPool.instance.allocate(tooMuchMemory) is null);
+
+        assert(MmapPool.instance.allocate(size_t.max) is null);
+
+        // initializeRegion() check.
+        tooMuchMemory = size_t.max - MmapPool.alignment_;
+        assert(MmapPool.instance.allocate(tooMuchMemory) is null);
+    }
+
+    /*
+     * Search for a block large enough to keep $(D_PARAM size) and split it
+     * into two blocks if the block is too large.
+     *
+     * Params:
+     *  size = Minimum size the block should have (aligned).
+     *
+     * Returns: Data the block points to or $(D_KEYWORD null).
+     */
+    private void* findBlock(const ref size_t size) shared pure nothrow @nogc
+    {
+        Block block1;
+        RegionLoop: for (auto r = head; r !is null; r = r.next)
+        {
+            block1 = cast(Block) (cast(void*) r + RegionEntry.sizeof);
+            do
+            {
+                if (block1.free && block1.size >= size)
+                {
+                    break RegionLoop;
+                }
+            }
+            while ((block1 = block1.next) !is null);
+        }
+        if (block1 is null)
+        {
+            return null;
+        }
+        else if (block1.size >= size + alignment_ + BlockEntry.sizeof)
+        { // Split the block if needed
+            Block block2 = cast(Block) (cast(void*) block1 + BlockEntry.sizeof + size);
+            block2.prev = block1;
+            block2.next = block1.next;
+            block2.free = true;
+            block2.size = block1.size - BlockEntry.sizeof - size;
+            block2.region = block1.region;
+
+            if (block1.next !is null)
+            {
+                block1.next.prev = block2;
+            }
+            block1.next = block2;
+            block1.size = size;
+        }
+        block1.free = false;
+        block1.region.blocks = block1.region.blocks + 1;
+
+        return cast(void*) block1 + BlockEntry.sizeof;
+    }
+
+    // Merge block with the next one.
+    private void mergeNext(Block block) shared const pure nothrow @safe @nogc
+    {
+        block.size = block.size + BlockEntry.sizeof + block.next.size;
+        if (block.next.next !is null)
+        {
+            block.next.next.prev = block;
+        }
+        block.next = block.next.next;
+    }
+
+    /**
+     * Deallocates a memory block.
+     *
+     * Params:
+     *  p = A pointer to the memory block to be freed.
+     *
+     * Returns: Whether the deallocation was successful.
+     */
+    bool deallocate(void[] p) shared pure nothrow @nogc
+    {
+        if (p.ptr is null)
+        {
+            return true;
+        }
+
+        Block block = cast(Block) (p.ptr - BlockEntry.sizeof);
+        if (block.region.blocks <= 1)
+        {
+            if (block.region.prev !is null)
+            {
+                block.region.prev.next = block.region.next;
+            }
+            else // Replace the list head. It is being deallocated
+            {
+                head = block.region.next;
+            }
+            if (block.region.next !is null)
+            {
+                block.region.next.prev = block.region.prev;
+            }
+            return unmapMemory(block.region, block.region.size);
+        }
+        // Merge blocks if neigbours are free.
+        if (block.next !is null && block.next.free)
+        {
+            mergeNext(block);
+        }
+        if (block.prev !is null && block.prev.free)
+        {
+            block.prev.size = block.prev.size + BlockEntry.sizeof + block.size;
+            if (block.next !is null)
+            {
+                block.next.prev = block.prev;
+            }
+            block.prev.next = block.next;
+        }
+        else
+        {
+            block.free = true;
+        }
+        block.region.blocks = block.region.blocks - 1;
+        return true;
+    }
+
+    ///
+    nothrow unittest
+    {
+        auto p = MmapPool.instance.allocate(20);
+
+        assert(MmapPool.instance.deallocate(p));
+    }
+
+    /**
+     * Reallocates a memory block in place if possible or returns
+     * $(D_KEYWORD false). This function cannot be used to allocate or
+     * deallocate memory, so if $(D_PARAM p) is $(D_KEYWORD null) or
+     * $(D_PARAM size) is `0`, it should return $(D_KEYWORD false).
+     *
+     * Params:
+     *  p    = A pointer to the memory block.
+     *  size = Size of the reallocated block.
+     *
+     * Returns: $(D_KEYWORD true) if successful, $(D_KEYWORD false) otherwise.
+     */
+    bool reallocateInPlace(ref void[] p, const size_t size)
+    shared pure nothrow @nogc
+    {
+        if (p is null || size == 0)
+        {
+            return false;
+        }
+        if (size <= p.length)
+        {
+            // Leave the block as is.
+            p = p.ptr[0 .. size];
+            return true;
+        }
+        Block block1 = cast(Block) (p.ptr - BlockEntry.sizeof);
+
+        if (block1.size >= size)
+        {
+            // Enough space in the current block.
+            p = p.ptr[0 .. size];
+            return true;
+        }
+        const dataSize = addAlignment(size);
+        const pAlignment = addAlignment(p.length);
+        assert(pAlignment >= p.length, "Invalid memory chunk length");
+        const delta = dataSize - pAlignment;
+
+        if (block1.next is null
+         || !block1.next.free
+         || dataSize < size
+         || block1.next.size + BlockEntry.sizeof < delta)
+        {
+            /* * It is the last block in the region
+             * * The next block is too small
+             * * The next block isn't free
+             * * Requested size is too large
+             */
+            return false;
+        }
+        if (block1.next.size >= delta + alignment_)
+        {
+            // Move size from block2 to block1.
+            block1.next.size = block1.next.size - delta;
+            block1.size = block1.size + delta;
+
+            auto block2 = cast(Block) (p.ptr + dataSize);
+            if (block1.next.next !is null)
+            {
+                block1.next.next.prev = block2;
+            }
+            // block1.next and block2 can overlap.
+            memmove(cast(void*) block2, cast(void*) block1.next, BlockEntry.sizeof);
+            block1.next = block2;
+        }
+        else
+        {
+            // The next block has enough space, but is too small for further
+            // allocations. Merge it with the current block.
+            mergeNext(block1);
+        }
+
+        p = p.ptr[0 .. size];
+        return true;
+    }
+
+    ///
+    nothrow unittest
+    {
+        void[] p;
+        assert(!MmapPool.instance.reallocateInPlace(p, 5));
+        assert(p is null);
+
+        p = MmapPool.instance.allocate(1);
+        auto orig = p.ptr;
+
+        assert(MmapPool.instance.reallocateInPlace(p, 2));
+        assert(p.length == 2);
+        assert(p.ptr == orig);
+
+        assert(MmapPool.instance.reallocateInPlace(p, 4));
+        assert(p.length == 4);
+        assert(p.ptr == orig);
+
+        assert(MmapPool.instance.reallocateInPlace(p, 2));
+        assert(p.length == 2);
+        assert(p.ptr == orig);
+
+        MmapPool.instance.deallocate(p);
+    }
+
+    /**
+     * Increases or decreases the size of a memory block.
+     *
+     * Params:
+     *  p    = A pointer to the memory block.
+     *  size = Size of the reallocated block.
+     *
+     * Returns: Whether the reallocation was successful.
+     */
+    bool reallocate(ref void[] p, const size_t size) shared pure nothrow @nogc
+    {
+        if (size == 0)
+        {
+            if (deallocate(p))
+            {
+                p = null;
+                return true;
+            }
+            return false;
+        }
+        else if (reallocateInPlace(p, size))
+        {
+            return true;
+        }
+        // Can't reallocate in place, allocate a new block,
+        // copy and delete the previous one.
+        void[] reallocP = allocate(size);
+        if (reallocP is null)
+        {
+            return false;
+        }
+        if (p !is null)
+        {
+            memcpy(reallocP.ptr, p.ptr, min(p.length, size));
+            deallocate(p);
+        }
+        p = reallocP;
+
+        return true;
+    }
+
+    ///
+    nothrow unittest
+    {
+        void[] p;
+        MmapPool.instance.reallocate(p, 10 * int.sizeof);
+        (cast(int[]) p)[7] = 123;
+
+        assert(p.length == 40);
+
+        MmapPool.instance.reallocate(p, 8 * int.sizeof);
+
+        assert(p.length == 32);
+        assert((cast(int[]) p)[7] == 123);
+
+        MmapPool.instance.reallocate(p, 20 * int.sizeof);
+        (cast(int[]) p)[15] = 8;
+
+        assert(p.length == 80);
+        assert((cast(int[]) p)[15] == 8);
+        assert((cast(int[]) p)[7] == 123);
+
+        MmapPool.instance.reallocate(p, 8 * int.sizeof);
+
+        assert(p.length == 32);
+        assert((cast(int[]) p)[7] == 123);
+
+        MmapPool.instance.deallocate(p);
+    }
+
+    static private shared(MmapPool) instantiate() nothrow @nogc
+    {
+        if (instance_ is null)
+        {
+            // Get system dependend page size.
+            version (Posix)
+            {
+                size_t pageSize = sysconf(_SC_PAGE_SIZE);
+                if (pageSize < 65536)
+                {
+                    pageSize = pageSize * 65536 / pageSize;
+                }
+            }
+            else version (Windows)
+            {
+                SYSTEM_INFO si;
+                GetSystemInfo(&si);
+                size_t pageSize = si.dwPageSize;
+            }
+
+            const instanceSize = addAlignment(__traits(classInstanceSize,
+                                              MmapPool));
+
+            Region head; // Will become soon our region list head
+            void* data = initializeRegion(instanceSize, head, pageSize);
+            if (data !is null)
+            {
+                memcpy(data, typeid(MmapPool).initializer.ptr, instanceSize);
+                instance_ = cast(shared MmapPool) data;
+                instance_.head = head;
+                instance_.pageSize = pageSize;
+            }
+        }
+        return instance_;
+    }
+
+    /**
+     * Static allocator instance and initializer.
+     *
+     * Returns: Global $(D_PSYMBOL MmapPool) instance.
+     */
+    static @property shared(MmapPool) instance() pure nothrow @nogc
+    {
+        return (cast(GetPureInstance!MmapPool) &instantiate)();
+    }
+
+    ///
+    nothrow unittest
+    {
+        assert(instance is instance);
+    }
+
+    /*
+     * Initializes a region for one element.
+     *
+     * Params:
+     *  size = Aligned size of the first data block in the region.
+     *  head = Region list head.
+     *
+     * Returns: A pointer to the data.
+     */
+    private static void* initializeRegion(const size_t size,
+                                          ref Region head,
+                                          const size_t pageSize)
+    pure nothrow @nogc
+    {
+        const regionSize = calculateRegionSize(size, pageSize);
+        if (regionSize < size)
+        {
+            return null;
+        }
+
+        void* p = mapMemory(regionSize);
+        if (p is null)
+        {
+            return null;
+        }
+
+        Region region = cast(Region) p;
+        region.blocks = 1;
+        region.size = regionSize;
+
+        // Set the pointer to the head of the region list
+        if (head !is null)
+        {
+            head.prev = region;
+        }
+        region.next = head;
+        region.prev = null;
+        head = region;
+
+        // Initialize the data block
+        void* memoryPointer = p + RegionEntry.sizeof;
+        Block block1 = cast(Block) memoryPointer;
+        block1.size = size;
+        block1.free = false;
+
+        // It is what we want to return
+        void* data = memoryPointer + BlockEntry.sizeof;
+
+        // Free block after data
+        memoryPointer = data + size;
+        Block block2 = cast(Block) memoryPointer;
+        block1.prev = block2.next = null;
+        block1.next = block2;
+        block2.prev = block1;
+        block2.size = regionSize - size - RegionEntry.sizeof - BlockEntry.sizeof * 2;
+        block2.free = true;
+        block1.region = block2.region = region;
+
+        return data;
+    }
+
+    private void* initializeRegion(const size_t size) shared pure nothrow @nogc
+    {
+        return initializeRegion(size, this.head, this.pageSize);
+    }
+
+    /*
+     * Params:
+     *  x = Space to be aligned.
+     *
+     * Returns: Aligned size of $(D_PARAM x).
+     */
+    private static size_t addAlignment(const size_t x) pure nothrow @safe @nogc
+    {
+        return (x - 1) / alignment_ * alignment_ + alignment_;
+    }
+
+    /*
+     * Params:
+     *  x        = Required space.
+     *  pageSize = Page size.
+     *
+     * Returns: Minimum region size (a multiple of $(D_PSYMBOL pageSize)).
+     */
+    private static size_t calculateRegionSize(ref const size_t x,
+                                              ref const size_t pageSize)
+    pure nothrow @safe @nogc
+    {
+        return (x + RegionEntry.sizeof + BlockEntry.sizeof * 2)
+             / pageSize * pageSize + pageSize;
+    }
+
+    /**
+     * Returns: Alignment offered.
+     */
+    @property uint alignment() shared const pure nothrow @safe @nogc
+    {
+        return alignment_;
+    }
+
+    private nothrow @nogc unittest
+    {
+        assert(MmapPool.instance.alignment == MmapPool.alignment_);
+    }
+
+    private enum uint alignment_ = 8;
+
+    private shared static MmapPool instance_;
+    private shared size_t pageSize;
+
+    private shared struct RegionEntry
+    {
+        Region prev;
+        Region next;
+        uint blocks;
+        size_t size;
+    }
+    private alias Region = shared RegionEntry*;
+    private shared Region head;
+
+    private shared struct BlockEntry
+    {
+        Block prev;
+        Block next;
+        Region region;
+        size_t size;
+        bool free;
+    }
+    private alias Block = shared BlockEntry*;
+}
+
+// A lot of allocations/deallocations, but it is the minimum caused a
+// segmentation fault because MmapPool reallocateInPlace moves a block wrong.
+private @nogc unittest
+{
+    auto a = MmapPool.instance.allocate(16);
+    auto d = MmapPool.instance.allocate(16);
+    auto b = MmapPool.instance.allocate(16);
+    auto e = MmapPool.instance.allocate(16);
+    auto c = MmapPool.instance.allocate(16);
+    auto f = MmapPool.instance.allocate(16);
+
+    MmapPool.instance.deallocate(a);
+    MmapPool.instance.deallocate(b);
+    MmapPool.instance.deallocate(c);
+
+    a = MmapPool.instance.allocate(50);
+    MmapPool.instance.reallocateInPlace(a, 64);
+    MmapPool.instance.deallocate(a);
+
+    a = MmapPool.instance.allocate(1);
+    auto tmp1 = MmapPool.instance.allocate(1);
+    auto h1 = MmapPool.instance.allocate(1);
+    auto tmp2 = cast(ubyte[]) MmapPool.instance.allocate(1);
+
+    auto h2 = MmapPool.instance.allocate(2);
+    tmp1 = MmapPool.instance.allocate(1);
+    MmapPool.instance.deallocate(h2);
+    MmapPool.instance.deallocate(h1);
+
+    h2 = MmapPool.instance.allocate(2);
+    h1 = MmapPool.instance.allocate(1);
+    MmapPool.instance.deallocate(h2);
+
+    auto rep = cast(void[]) tmp2;
+    MmapPool.instance.reallocate(rep, tmp1.length);
+    tmp2 = cast(ubyte[]) rep;
+
+    MmapPool.instance.reallocate(tmp1, 9);
+
+    rep = cast(void[]) tmp2;
+    MmapPool.instance.reallocate(rep, tmp1.length);
+    tmp2 = cast(ubyte[]) rep;
+    MmapPool.instance.reallocate(tmp1, 17);
+
+    tmp2[$ - 1] = 0;
+
+    MmapPool.instance.deallocate(tmp1);
+
+    b = MmapPool.instance.allocate(16);
+
+    MmapPool.instance.deallocate(h1);
+    MmapPool.instance.deallocate(a);
+    MmapPool.instance.deallocate(b);
+    MmapPool.instance.deallocate(d);
+    MmapPool.instance.deallocate(e);
+    MmapPool.instance.deallocate(f);
+}

source/tanya/memory/package.d

@@ -3,205 +3,487 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * Dynamic memory management.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
  * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
 module tanya.memory;
 
-public import tanya.memory.allocator;
+import core.exception;
-public import std.experimental.allocator : make, makeArray, expandArray, shrinkArray, IAllocator;
+import std.algorithm.iteration;
-import core.atomic;
+import std.algorithm.mutation;
-import core.stdc.stdlib;
+import std.conv;
+import std.range;
 import std.traits;
+public import tanya.memory.allocator;
+import tanya.memory.mmappool;
 
-version (Windows)
+/**
+ * The mixin generates common methods for classes and structs using
+ * allocators. It provides a protected member, constructor and a read-only property,
+ * that checks if an allocator was already set and sets it to the default
+ * one, if not (useful for structs which don't have a default constructor).
+ */
+mixin template DefaultAllocator()
 {
-	import core.sys.windows.windows;
+    /// Allocator.
-}
+    protected shared Allocator allocator_;
-else version (Posix)
-{
-	public import tanya.memory.ullocator;
-	import core.sys.posix.pthread;
-}
 
-@nogc:
+    /**
-
+     * Params:
-version (Windows)
+     *  allocator = The allocator should be used.
-{
+     *
-	package alias Mutex = CRITICAL_SECTION;
+     * Precondition: $(D_INLINECODE allocator_ !is null)
-	package alias destroyMutex = DeleteCriticalSection;
+     */
-}
+    this(shared Allocator allocator) pure nothrow @safe @nogc
-else version (Posix)
+    in
-{
-	package alias Mutex = pthread_mutex_t;
-    package void destroyMutex(pthread_mutex_t* mtx)
     {
-        pthread_mutex_destroy(mtx) && assert(0);
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.allocator_ = allocator;
+    }
+
+    /**
+     * This property checks if the allocator was set in the constructor
+     * and sets it to the default one, if not.
+     *
+     * Returns: Used allocator.
+     *
+     * Postcondition: $(D_INLINECODE allocator !is null)
+     */
+    protected @property shared(Allocator) allocator() pure nothrow @safe @nogc
+    out (allocator)
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        if (allocator_ is null)
+        {
+            allocator_ = defaultAllocator;
+        }
+        return allocator_;
+    }
+
+    /// Ditto.
+    @property shared(Allocator) allocator() const pure nothrow @trusted @nogc
+    out (allocator)
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        if (allocator_ is null)
+        {
+            return defaultAllocator;
+        }
+        return cast(shared Allocator) allocator_;
     }
 }
 
-@property void defaultAllocator(Allocator allocator) @safe nothrow
+// From druntime
+extern (C)
+private void _d_monitordelete(Object h, bool det) pure nothrow @nogc;
+
+shared Allocator allocator;
+
+shared static this() nothrow @nogc
 {
-	_defaultAllocator = allocator;
+    allocator = MmapPool.instance;
 }
 
-@property Allocator defaultAllocator() @safe nothrow
+private shared(Allocator) getAllocatorInstance() nothrow @nogc
 {
-	return _defaultAllocator;
+    return allocator;
-}
-
-static this() @safe nothrow
-{
-	defaultAllocator = Ullocator.instance;
-}
-
-package struct Monitor
-{
-	Object.Monitor impl; // for user-level monitors
-	void delegate(Object) @nogc[] devt; // for internal monitors
-	size_t refs; // reference count
-	version (Posix)
-	{
-		Mutex mtx;
-	}
-}
-
-package @property ref shared(Monitor*) monitor(Object h) pure nothrow
-{
-    return *cast(shared Monitor**)&h.__monitor;
 }
 
 /**
- * Destroys and then deallocates (using $(D_PARAM allocator)) the class
+ * Returns: Default allocator.
- * object referred to by a $(D_KEYWORD class) or $(D_KEYWORD interface)
+ *
- * reference. It is assumed the respective entities had been allocated with
+ * Postcondition: $(D_INLINECODE allocator !is null).
- * the same allocator.
+ */
+@property shared(Allocator) defaultAllocator() pure nothrow @trusted @nogc
+out (allocator)
+{
+    assert(allocator !is null);
+}
+body
+{
+    return (cast(GetPureInstance!Allocator) &getAllocatorInstance)();
+}
+
+/**
+ * Sets the default allocator.
  *
  * Params:
- * 	A         = The type of the allocator used for the ojbect allocation.
+ *  allocator = $(D_PSYMBOL Allocator) instance.
- * 	T         = The type of the object that should be destroyed.
+ *
- * 	allocator = The allocator used for the object allocation.
+ * Precondition: $(D_INLINECODE allocator !is null).
- * 	p         = The object should be destroyed.
  */
-void finalize(A, T)(auto ref A allocator, ref T p)
+@property void defaultAllocator(shared(Allocator) allocator) nothrow @safe @nogc
+in
+{
+    assert(allocator !is null);
+}
+body
+{
+    .allocator = allocator;
+}
+
+private nothrow @nogc unittest
+{
+    import tanya.memory.mallocator;
+
+    auto oldAllocator = defaultAllocator;
+    defaultAllocator = Mallocator.instance;
+    assert(defaultAllocator is Mallocator.instance);
+
+    defaultAllocator = oldAllocator;
+}
+
+/**
+ * Returns the size in bytes of the state that needs to be allocated to hold an
+ * object of type $(D_PARAM T).
+ *
+ * Params:
+ *  T = Object type.
+ */
+template stateSize(T)
+{
+    static if (is(T == class) || is(T == interface))
+    {
+        enum stateSize = __traits(classInstanceSize, T);
+    }
+    else
+    {
+        enum stateSize = T.sizeof;
+    }
+}
+
+/**
+ * Params:
+ *  size      = Raw size.
+ *  alignment = Alignment.
+ *
+ * Returns: Aligned size.
+ */
+size_t alignedSize(const size_t size, const size_t alignment = 8)
+pure nothrow @safe @nogc
+{
+    return (size - 1) / alignment * alignment + alignment;
+}
+
+/**
+ * Internal function used to create, resize or destroy a dynamic array. It
+ * may throw $(D_PSYMBOL OutOfMemoryError). The new
+ * allocated part of the array isn't initialized. This function can be trusted
+ * only in the data structures that can ensure that the array is
+ * allocated/rellocated/deallocated with the same allocator.
+ *
+ * Params:
+ *  T         = Element type of the array being created.
+ *  allocator = The allocator used for getting memory.
+ *  array     = A reference to the array being changed.
+ *  length    = New array length.
+ *
+ * Returns: $(D_PARAM array).
+ */
+package(tanya) T[] resize(T)(shared Allocator allocator,
+                             auto ref T[] array,
+                             const size_t length) @trusted
+{
+    if (length == 0)
+    {
+        if (allocator.deallocate(array))
+        {
+            return null;
+        }
+        else
+        {
+            onOutOfMemoryErrorNoGC();
+        }
+    }
+
+    void[] buf = array;
+    if (!allocator.reallocate(buf, length * T.sizeof))
+    {
+        onOutOfMemoryErrorNoGC();
+    }
+    // Casting from void[] is unsafe, but we know we cast to the original type.
+    array = cast(T[]) buf;
+
+    return array;
+}
+
+private unittest
+{
+    int[] p;
+
+    p = defaultAllocator.resize(p, 20);
+    assert(p.length == 20);
+
+    p = defaultAllocator.resize(p, 30);
+    assert(p.length == 30);
+
+    p = defaultAllocator.resize(p, 10);
+    assert(p.length == 10);
+
+    p = defaultAllocator.resize(p, 0);
+    assert(p is null);
+}
+
+/*
+ * Destroys the object.
+ * Returns the memory should be freed.
+ */
+package(tanya) void[] finalize(T)(ref T* p)
+{
+    static if (hasElaborateDestructor!T)
+    {
+        destroy(*p);
+    }
+    return (cast(void*) p)[0 .. T.sizeof];
+}
+
+package(tanya) void[] finalize(T)(ref T p)
     if (is(T == class) || is(T == interface))
 {
+    if (p is null)
+    {
+        return null;
+    }
     static if (is(T == interface))
     {
+        version(Windows)
+        {
+            import core.sys.windows.unknwn : IUnknown;
+            static assert(!is(T : IUnknown), "COM interfaces can't be destroyed in "
+                                           ~ __PRETTY_FUNCTION__);
+        }
         auto ob = cast(Object) p;
     }
     else
     {
         alias ob = p;
     }
-	auto pp = cast(void*) ob;
+    auto ptr = cast(void*) ob;
-	auto ppv = cast(void**) pp;
+    auto support = ptr[0 .. typeid(ob).initializer.length];
-	if (!pp || !*ppv)
+
+    auto ppv = cast(void**) ptr;
+    if (!*ppv)
     {
-		return;
+        return null;
     }
-	auto support = (cast(void*) ob)[0 .. typeid(ob).initializer.length];
     auto pc = cast(ClassInfo*) *ppv;
+    scope (exit)
+    {
+        *ppv = null;
+    }
+
     auto c = *pc;
     do
     {
+        // Assume the destructor is @nogc. Leave it nothrow since the destructor
+        // shouldn't throw and if it does, it is an error anyway.
         if (c.destructor)
         {
-			(cast(void function(Object)) c.destructor)(ob);
+            alias DtorType = void function(Object) pure nothrow @safe @nogc;
+            (cast(DtorType) c.destructor)(ob);
         }
-	} while ((c = c.base) !is null);
+    }
+    while ((c = c.base) !is null);
 
-	// Take care of monitors for synchronized blocks
+    if (ppv[1]) // if monitor is not null
-	if (ppv[1])
     {
-		shared(Monitor)* m = atomicLoad!(MemoryOrder.acq)(ob.monitor);
+        _d_monitordelete(cast(Object) ptr, true);
-		if (m !is null)
-		{
-			auto mc = cast(Monitor*) m;
-			if (!atomicOp!("-=")(m.refs, cast(size_t) 1))
-			{
-				foreach (v; mc.devt)
-				{
-					if (v)
-					{
-						v(ob);
     }
-				}
+    return support;
-				if (mc.devt.ptr)
+}
-				{
-					free(mc.devt.ptr);
-				}
-				destroyMutex(&mc.mtx);
-				free(mc);
-				atomicStore!(MemoryOrder.rel)(ob.monitor, null);
-			}
-		}
-	}
-	*ppv = null;
 
-	allocator.deallocate(support);
+package(tanya) void[] finalize(T)(ref T[] p)
+{
+    static if (hasElaborateDestructor!(typeof(p[0])))
+    {
+        p.each!((ref e) => destroy(e));
+    }
+    return p;
+}
+
+/**
+ * Destroys and deallocates $(D_PARAM p) of type $(D_PARAM T).
+ * It is assumed the respective entities had been allocated with the same
+ * allocator.
+ *
+ * Params:
+ *  T         = Type of $(D_PARAM p).
+ *  allocator = Allocator the $(D_PARAM p) was allocated with.
+ *  p         = Object or array to be destroyed.
+ */
+void dispose(T)(shared Allocator allocator, auto ref T p)
+{
+    () @trusted { allocator.deallocate(finalize(p)); }();
     p = null;
 }
 
-/// Ditto.
+private unittest
-void finalize(A, T)(auto ref A allocator, ref T *p)
-	if (is(T == struct))
 {
-    if (p is null)
+    struct S
     {
-		return;
+        ~this()
-	}
-	static if (hasElaborateDestructor!T)
         {
-		*p.__xdtor();
         }
-	allocator.deallocate((cast(void*)p)[0 .. T.sizeof]);
+    }
-	p = null;
+    auto p = cast(S[]) defaultAllocator.allocate(S.sizeof);
+
+    defaultAllocator.dispose(p);
 }
 
-/// Ditto.
+// Works with interfaces.
-void finalize(A, T)(auto ref A allocator, ref T[] p)
+private pure unittest
 {
-	static if (hasElaborateDestructor!T)
+    interface I
     {
-		foreach (ref e; p)
+    }
+    class C : I
     {
-			finalize(allocator, e);
     }
-	}
+    auto c = defaultAllocator.make!C();
-	allocator.deallocate(p);
+    I i = c;
-	p = null;
+
+    defaultAllocator.dispose(i);
+    defaultAllocator.dispose(i);
 }
 
-bool resizeArray(T, A)(auto ref A allocator, ref T[] array, in size_t length)
+/**
-@trusted
+ * Constructs a new class instance of type $(D_PARAM T) using $(D_PARAM args)
+ * as the parameter list for the constructor of $(D_PARAM T).
+ *
+ * Params:
+ *  T         = Class type.
+ *  A         = Types of the arguments to the constructor of $(D_PARAM T).
+ *  allocator = Allocator.
+ *  args      = Constructor arguments of $(D_PARAM T).
+ * 
+ * Returns: Newly created $(D_PSYMBOL T).
+ *
+ * Precondition: $(D_INLINECODE allocator !is null)
+ */
+T make(T, A...)(shared Allocator allocator, auto ref A args)
+if (is(T == class))
+in
 {
-	if (length == array.length)
+    assert(allocator !is null);
+}
+body
+{
+    T ret;
+    const size = stateSize!T;
+
+    auto mem = (() @trusted => allocator.allocate(size))();
+    if (mem is null)
     {
-		return true;
+        onOutOfMemoryError();
     }
-	if (array is null && length > 0)
+    scope (failure)
     {
-		array = makeArray!T(allocator, length);
+        () @trusted { allocator.deallocate(mem); }();
-		return array !is null;
     }
-	if (length == 0)
+
-	{
+    ret = emplace!T(mem[0 .. size], args);
-		finalize(allocator, array);
+
-		return true;
+    return ret;
-	}
-	void[] buf = array;
-	if (!allocator.reallocate(buf, length * T.sizeof))
-	{
-		return false;
-	}
-	array = cast(T[]) buf;
-	return true;
 }
 
-enum bool isFinalizable(T) = is(T == class) || is(T == interface)
+/**
-                          || hasElaborateDestructor!T || isDynamicArray!T;
+ * Constructs a value object of type $(D_PARAM T) using $(D_PARAM args)
+ * as the parameter list for the constructor of $(D_PARAM T) and returns a
+ * pointer to the new object.
+ *
+ * Params:
+ *  T         = Object type.
+ *  A         = Types of the arguments to the constructor of $(D_PARAM T).
+ *  allocator = Allocator.
+ *  args      = Constructor arguments of $(D_PARAM T).
+ * 
+ * Returns: Pointer to the created object.
+ *
+ * Precondition: $(D_INLINECODE allocator !is null)
+ */
+T* make(T, A...)(shared Allocator allocator, auto ref A args)
+if (!is(T == interface)
+ && !is(T == class)
+ && !isAssociativeArray!T
+ && !isArray!T)
+in
+{
+    assert(allocator !is null);
+}
+body
+{
+    typeof(return) ret;
+    const size = stateSize!T;
 
-private Allocator _defaultAllocator;
+    auto mem = (() @trusted => allocator.allocate(size))();
+    if (mem is null)
+    {
+        onOutOfMemoryError();
+    }
+    scope (failure)
+    {
+        () @trusted { allocator.deallocate(mem); }();
+    }
+
+    auto ptr = (() @trusted => (cast(T*) mem[0 .. size].ptr))();
+    ret = emplace!T(ptr, args);
+
+    return ret;
+}
+
+///
+unittest
+{
+    int* i = defaultAllocator.make!int(5);
+    assert(*i == 5);
+    defaultAllocator.dispose(i);
+}
+
+/**
+ * Constructs a new array with $(D_PARAM size) elements.
+ *
+ * Params:
+ *  T         = Array type.
+ *  allocator = Allocator.
+ *  size      = Array size.
+ *
+ * Returns: Newly created array.
+ *
+ * Precondition: $(D_INLINECODE allocator !is null
+ *                           && n <= size_t.max / ElementType!T.sizeof)
+ */
+T make(T)(shared Allocator allocator, const size_t n)
+if (isArray!T)
+in
+{
+    assert(allocator !is null);
+    assert(n <= size_t.max / ElementType!T.sizeof);
+}
+body
+{
+    auto ret = allocator.resize!(ElementType!T)(null, n);
+    ret.uninitializedFill(ElementType!T.init);
+    return ret;
+}
+
+///
+unittest
+{
+    int[] i = defaultAllocator.make!(int[])(2);
+    assert(i.length == 2);
+    assert(i[0] == int.init && i[1] == int.init);
+    defaultAllocator.dispose(i);
+}

source/tanya/memory/smartref.d

@@ -0,0 +1,923 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Smart pointers.
+ *
+ * A smart pointer is an object that wraps a raw pointer or a reference
+ * (class, array) to manage its lifetime.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.memory.smartref;
+
+import core.exception;
+import std.algorithm.comparison;
+import std.algorithm.mutation;
+import std.conv;
+import std.range;
+import std.traits;
+import tanya.memory;
+
+private template Payload(T)
+{
+    static if (is(T == class) || is(T == interface) || isArray!T)
+    {
+        alias Payload = T;
+    }
+    else
+    {
+        alias Payload = T*;
+    }
+}
+
+private final class RefCountedStore(T)
+{
+    T payload;
+    size_t counter = 1;
+
+    size_t opUnary(string op)()
+    if (op == "--" || op == "++")
+    in
+    {
+        assert(this.counter > 0);
+    }
+    body
+    {
+        mixin("return " ~ op ~ "counter;");
+    }
+
+    int opCmp(const size_t counter)
+    {
+        if (this.counter > counter)
+        {
+            return 1;
+        }
+        else if (this.counter < counter)
+        {
+            return -1;
+        }
+        else
+        {
+            return 0;
+        }
+    }
+}
+
+private void separateDeleter(T)(RefCountedStore!T storage,
+                                shared Allocator allocator)
+{
+    allocator.dispose(storage.payload);
+    allocator.dispose(storage);
+}
+
+private void unifiedDeleter(T)(RefCountedStore!T storage,
+                               shared Allocator allocator)
+{
+    auto ptr1 = finalize(storage);
+    auto ptr2 = finalize(storage.payload);
+    allocator.deallocate(ptr1.ptr[0 .. ptr1.length + ptr2.length]);
+}
+
+/**
+ * Reference-counted object containing a $(D_PARAM T) value as payload.
+ * $(D_PSYMBOL RefCounted) keeps track of all references of an object, and
+ * when the reference count goes down to zero, frees the underlying store.
+ *
+ * Params:
+ *  T = Type of the reference-counted value.
+ */
+struct RefCounted(T)
+{
+    private alias Storage = RefCountedStore!(Payload!T);
+
+    private Storage storage;
+    private void function(Storage storage,
+                          shared Allocator allocator) @nogc deleter;
+
+    invariant
+    {
+        assert(this.storage is null || this.allocator_ !is null);
+        assert(this.storage is null || this.deleter !is null);
+    }
+
+    /**
+     * Takes ownership over $(D_PARAM value), setting the counter to 1.
+     * $(D_PARAM value) may be a pointer, an object or a dynamic array.
+     *
+     * Params:
+     *  value     = Value whose ownership is taken over.
+     *  allocator = Allocator used to destroy the $(D_PARAM value) and to
+     *              allocate/deallocate internal storage.
+     *
+     * Precondition: $(D_INLINECODE allocator !is null)
+     */
+    this(Payload!T value, shared Allocator allocator = defaultAllocator)
+    {
+        this(allocator);
+        this.storage = allocator.make!Storage();
+        this.deleter = &separateDeleter!(Payload!T);
+
+        this.storage.payload = value;
+    }
+
+    /// Ditto.
+    this(shared Allocator allocator)
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.allocator_ = allocator;
+    }
+
+    /**
+     * Increases the reference counter by one.
+     */
+    this(this)
+    {
+        if (count != 0)
+        {
+            ++this.storage;
+        }
+    }
+
+    /**
+     * Decreases the reference counter by one.
+     *
+     * If the counter reaches 0, destroys the owned object.
+     */
+    ~this()
+    {
+        if (this.storage !is null && !(this.storage > 0 && --this.storage))
+        {
+            deleter(this.storage, allocator);
+        }
+    }
+
+    /**
+     * Takes ownership over $(D_PARAM rhs). Initializes this
+     * $(D_PSYMBOL RefCounted) if needed.
+     *
+     * If it is the last reference of the previously owned object,
+     * it will be destroyed.
+     *
+     * To reset $(D_PSYMBOL RefCounted) assign $(D_KEYWORD null).
+     *
+     * If the allocator wasn't set before, $(D_PSYMBOL defaultAllocator) will
+     * be used. If you need a different allocator, create a new
+     * $(D_PSYMBOL RefCounted) and assign it.
+     *
+     * Params:
+     *  rhs = New object.
+     *
+     * Returns: $(D_KEYWORD this).
+     */
+    ref typeof(this) opAssign(Payload!T rhs)
+    {
+        if (this.storage is null)
+        {
+            this.storage = allocator.make!Storage();
+            this.deleter = &separateDeleter!(Payload!T);
+        }
+        else if (this.storage > 1)
+        {
+            --this.storage;
+            this.storage = allocator.make!Storage();
+            this.deleter = &separateDeleter!(Payload!T);
+        }
+        else
+        {
+            finalize(this.storage.payload);
+            this.storage.payload = Payload!T.init;
+        }
+        this.storage.payload = rhs;
+        return this;
+    }
+
+    private @nogc unittest
+    {
+        auto rc = defaultAllocator.refCounted!int(5);
+        rc = defaultAllocator.make!int(7);
+        assert(*rc == 7);
+    }
+
+    /// Ditto.
+    ref typeof(this) opAssign(typeof(null))
+    {
+        if (this.storage is null)
+        {
+            return this;
+        }
+        else if (this.storage > 1)
+        {
+            --this.storage;
+        }
+        else
+        {
+            deleter(this.storage, allocator);
+        }
+        this.storage = null;
+
+        return this;
+    }
+
+    private @nogc unittest
+    {
+        RefCounted!int rc;
+        assert(!rc.isInitialized);
+        rc = null;
+        assert(!rc.isInitialized);
+    }
+
+    /// Ditto.
+    ref typeof(this) opAssign(typeof(this) rhs)
+    {
+        swap(this.allocator_, rhs.allocator_);
+        swap(this.storage, rhs.storage);
+        swap(this.deleter, rhs.deleter);
+        return this;
+    }
+
+    /**
+     * Returns: Reference to the owned object.
+     *
+     * Precondition: $(D_INLINECODE cound > 0).
+     */
+    inout(Payload!T) get() inout
+    in
+    {
+        assert(count > 0, "Attempted to access an uninitialized reference");
+    }
+    body
+    {
+        return this.storage.payload;
+    }
+
+    version (D_Ddoc)
+    {
+        /**
+         * Dereferences the pointer. It is defined only for pointers, not for
+         * reference types like classes, that can be accessed directly.
+         *
+         * Params:
+         *  op = Operation. 
+         *
+         * Returns: Reference to the pointed value.
+         */
+        ref inout(T) opUnary(string op)() inout
+        if (op == "*");
+    }
+    else static if (isPointer!(Payload!T))
+    {
+        ref inout(T) opUnary(string op)() inout
+        if (op == "*")
+        {
+            return *this.storage.payload;
+        }
+    }
+
+    /**
+     * Returns: Whether this $(D_PSYMBOL RefCounted) already has an internal 
+     *          storage.
+     */
+    @property bool isInitialized() const
+    {
+        return this.storage !is null;
+    }
+
+    /**
+     * Returns: The number of $(D_PSYMBOL RefCounted) instances that share
+     *          ownership over the same pointer (including $(D_KEYWORD this)).
+     *          If this $(D_PSYMBOL RefCounted) isn't initialized, returns `0`.
+     */
+    @property size_t count() const
+    {
+        return this.storage is null ? 0 : this.storage.counter;
+    }
+
+    mixin DefaultAllocator;
+    alias get this;
+}
+
+///
+unittest
+{
+    auto rc = RefCounted!int(defaultAllocator.make!int(5), defaultAllocator);
+    auto val = rc.get();
+
+    *val = 8;
+    assert(*rc.storage.payload == 8);
+
+    val = null;
+    assert(rc.storage.payload !is null);
+    assert(*rc.storage.payload == 8);
+
+    *rc = 9;
+    assert(*rc.storage.payload == 9);
+}
+
+private @nogc unittest
+{
+    auto rc = defaultAllocator.refCounted!int(5);
+
+    void func(RefCounted!int param) @nogc
+    {
+        assert(param.count == 2);
+        param = defaultAllocator.make!int(7);
+        assert(param.count == 1);
+        assert(*param == 7);
+    }
+    func(rc);
+    assert(rc.count == 1);
+    assert(*rc == 5);
+}
+
+private @nogc unittest
+{
+    RefCounted!int rc;
+
+    void func(RefCounted!int param) @nogc
+    {
+        assert(param.count == 0);
+        param = defaultAllocator.make!int(7);
+        assert(param.count == 1);
+        assert(*param == 7);
+    }
+    func(rc);
+    assert(rc.count == 0);
+}
+
+private unittest
+{
+    RefCounted!int rc1, rc2;
+    static assert(is(typeof(rc1 = rc2)));
+}
+
+version (unittest)
+{
+    private class A
+    {
+        uint *destroyed;
+
+        this(ref uint destroyed) @nogc
+        {
+            this.destroyed = &destroyed;
+        }
+
+        ~this() @nogc
+        {
+            ++(*destroyed);
+        }
+    }
+
+    private struct B
+    {
+        int prop;
+        @disable this();
+        this(int param1) @nogc
+        {
+            prop = param1;
+        }
+    }
+}
+
+private @nogc unittest
+{
+    uint destroyed;
+    auto a = defaultAllocator.make!A(destroyed);
+
+    assert(destroyed == 0);
+    {
+        auto rc = RefCounted!A(a, defaultAllocator);
+        assert(rc.count == 1);
+
+        void func(RefCounted!A rc) @nogc
+        {
+            assert(rc.count == 2);
+        }
+        func(rc);
+
+        assert(rc.count == 1);
+    }
+    assert(destroyed == 1);
+
+    RefCounted!int rc;
+    assert(rc.count == 0);
+    rc = defaultAllocator.make!int(8);
+    assert(rc.count == 1);
+}
+
+private @nogc unittest
+{
+    auto rc = RefCounted!int(defaultAllocator);
+    assert(!rc.isInitialized);
+    assert(rc.allocator is defaultAllocator);
+}
+
+private @nogc unittest
+{
+    auto rc = defaultAllocator.refCounted!int(5);
+    assert(rc.count == 1);
+
+    void func(RefCounted!int rc) @nogc
+    {
+        assert(rc.count == 2);
+        rc = null;
+        assert(!rc.isInitialized);
+        assert(rc.count == 0);
+    }
+
+    assert(rc.count == 1);
+    func(rc);
+    assert(rc.count == 1);
+
+    rc = null;
+    assert(!rc.isInitialized);
+    assert(rc.count == 0);
+}
+
+private unittest
+{
+    auto rc = defaultAllocator.refCounted!int(5);
+    assert(*rc == 5);
+
+    void func(RefCounted!int rc) @nogc
+    {
+        assert(rc.count == 2);
+        rc = defaultAllocator.refCounted!int(4);
+        assert(*rc == 4);
+        assert(rc.count == 1);
+    }
+    func(rc);
+    assert(*rc == 5);
+}
+
+private unittest
+{
+    static assert(is(typeof(RefCounted!int.storage.payload) == int*));
+    static assert(is(typeof(RefCounted!A.storage.payload) == A));
+
+    static assert(is(RefCounted!B));
+    static assert(is(RefCounted!A));
+}
+
+/**
+ * Constructs a new object of type $(D_PARAM T) and wraps it in a
+ * $(D_PSYMBOL RefCounted) using $(D_PARAM args) as the parameter list for
+ * the constructor of $(D_PARAM T).
+ *
+ * This function is more efficient than the using of $(D_PSYMBOL RefCounted)
+ * directly, since it allocates only ones (the internal storage and the
+ * object).
+ *
+ * Params:
+ *  T         = Type of the constructed object.
+ *  A         = Types of the arguments to the constructor of $(D_PARAM T).
+ *  allocator = Allocator.
+ *  args      = Constructor arguments of $(D_PARAM T).
+ * 
+ * Returns: Newly created $(D_PSYMBOL RefCounted!T).
+ *
+ * Precondition: $(D_INLINECODE allocator !is null)
+ */
+RefCounted!T refCounted(T, A...)(shared Allocator allocator, auto ref A args)
+if (!is(T == interface) && !isAbstractClass!T
+ && !isAssociativeArray!T && !isArray!T)
+in
+{
+    assert(allocator !is null);
+}
+body
+{
+    auto rc = typeof(return)(allocator);
+
+    const storageSize = alignedSize(stateSize!(RefCounted!T.Storage));
+    const size = alignedSize(stateSize!T + storageSize);
+
+    auto mem = (() @trusted => allocator.allocate(size))();
+    if (mem is null)
+    {
+        onOutOfMemoryError();
+    }
+    scope (failure)
+    {
+        () @trusted { allocator.deallocate(mem); }();
+    }
+    rc.storage = emplace!((RefCounted!T.Storage))(mem[0 .. storageSize]);
+
+    static if (is(T == class))
+    {
+        rc.storage.payload = emplace!T(mem[storageSize .. $], args);
+    }
+    else
+    {
+        auto ptr = (() @trusted => (cast(T*) mem[storageSize .. $].ptr))();
+        rc.storage.payload = emplace!T(ptr, args);
+    }
+    rc.deleter = &unifiedDeleter!(Payload!T);
+    return rc;
+}
+
+/**
+ * Constructs a new array with $(D_PARAM size) elements and wraps it in a
+ * $(D_PSYMBOL RefCounted).
+ *
+ * Params:
+ *  T         = Array type.
+ *  size      = Array size.
+ *  allocator = Allocator.
+ *
+ * Returns: Newly created $(D_PSYMBOL RefCounted!T).
+ *
+ * Precondition: $(D_INLINECODE allocator !is null
+ *                           && size <= size_t.max / ElementType!T.sizeof)
+ */
+RefCounted!T refCounted(T)(shared Allocator allocator, const size_t size)
+@trusted
+if (isArray!T)
+in
+{
+    assert(allocator !is null);
+    assert(size <= size_t.max / ElementType!T.sizeof);
+}
+body
+{
+    return RefCounted!T(allocator.make!T(size), allocator);
+}
+
+///
+unittest
+{
+    auto rc = defaultAllocator.refCounted!int(5);
+    assert(rc.count == 1);
+
+    void func(RefCounted!int param) @nogc
+    {
+        if (param.count == 2)
+        {
+            func(param);
+        }
+        else
+        {
+            assert(param.count == 3);
+        }
+    }
+    func(rc);
+
+    assert(rc.count == 1);
+}
+
+private @nogc unittest
+{
+    struct E
+    {
+    }
+    auto b = defaultAllocator.refCounted!B(15);
+    static assert(is(typeof(b.storage.payload) == B*));
+    static assert(is(typeof(b.prop) == int));
+    static assert(!is(typeof(defaultAllocator.refCounted!B())));
+
+    static assert(is(typeof(defaultAllocator.refCounted!E())));
+    static assert(!is(typeof(defaultAllocator.refCounted!E(5))));
+    {
+        auto rc = defaultAllocator.refCounted!B(3);
+        assert(rc.get().prop == 3);
+    }
+    {
+        auto rc = defaultAllocator.refCounted!E();
+        assert(rc.count);
+    }
+}
+
+private @nogc unittest
+{
+    auto rc = defaultAllocator.refCounted!(int[])(5);
+    assert(rc.length == 5);
+}
+
+private @nogc unittest
+{
+    auto p1 = defaultAllocator.make!int(5);
+    auto p2 = p1;
+    auto rc = RefCounted!int(p1, defaultAllocator);
+    assert(rc.get() is p2);
+}
+
+private @nogc unittest
+{
+    static bool destroyed = false;
+
+    struct F
+    {
+        ~this() @nogc
+        {
+            destroyed = true;
+        }
+    }
+    {
+        auto rc = defaultAllocator.refCounted!F();
+    }
+    assert(destroyed);
+}
+
+/**
+ * $(D_PSYMBOL Unique) stores an object that gets destroyed at the end of its scope.
+ *
+ * Params:
+ *  T = Value type.
+ */
+struct Unique(T)
+{
+    private Payload!T payload;
+
+    invariant
+    {
+        assert(payload is null || allocator_ !is null);
+    }
+
+    /**
+     * Takes ownership over $(D_PARAM value), setting the counter to 1.
+     * $(D_PARAM value) may be a pointer, an object or a dynamic array.
+     *
+     * Params:
+     *  value     = Value whose ownership is taken over.
+     *  allocator = Allocator used to destroy the $(D_PARAM value) and to
+     *              allocate/deallocate internal storage.
+     *
+     * Precondition: $(D_INLINECODE allocator !is null)
+     */
+    this(Payload!T value, shared Allocator allocator = defaultAllocator)
+    {
+        this(allocator);
+        this.payload = value;
+    }
+
+    /// Ditto.
+    this(shared Allocator allocator)
+    in
+    {
+        assert(allocator !is null);
+    }
+    body
+    {
+        this.allocator_ = allocator;
+    }
+
+    /**
+     * $(D_PSYMBOL Unique) is noncopyable.
+     */
+    @disable this(this);
+
+    /**
+     * Destroys the owned object.
+     */
+    ~this()
+    {
+        allocator.dispose(this.payload);
+    }
+
+    /**
+     * Initialized this $(D_PARAM Unique) and takes ownership over
+     * $(D_PARAM rhs).
+     *
+     * To reset $(D_PSYMBOL Unique) assign $(D_KEYWORD null).
+     *
+     * If the allocator wasn't set before, $(D_PSYMBOL defaultAllocator) will
+     * be used. If you need a different allocator, create a new
+     * $(D_PSYMBOL Unique) and assign it.
+     *
+     * Params:
+     *  rhs = New object.
+     *
+     * Returns: $(D_KEYWORD this).
+     */
+    ref typeof(this) opAssign(Payload!T rhs)
+    {
+        allocator.dispose(this.payload);
+        this.payload = rhs;
+        return this;
+    }
+
+    /// Ditto.
+    ref typeof(this) opAssign(typeof(null))
+    {
+        allocator.dispose(this.payload);
+        return this;
+    }
+
+    /// Ditto.
+    ref typeof(this) opAssign(typeof(this) rhs)
+    {
+        swap(this.allocator_, rhs.allocator_);
+        swap(this.payload, rhs.payload);
+
+        return this;
+    }
+
+    ///
+    @nogc unittest
+    {
+        auto rc = defaultAllocator.unique!int(5);
+        rc = defaultAllocator.make!int(7);
+        assert(*rc == 7);
+    }
+
+    /**
+     * Returns: Reference to the owned object.
+     */
+    inout(Payload!T) get() inout
+    {
+        return this.payload;
+    }
+
+    version (D_Ddoc)
+    {
+        /**
+         * Dereferences the pointer. It is defined only for pointers, not for
+         * reference types like classes, that can be accessed directly.
+         *
+         * Params:
+         *  op = Operation. 
+         *
+         * Returns: Reference to the pointed value.
+         */
+        ref inout(T) opUnary(string op)() inout
+        if (op == "*");
+    }
+    else static if (isPointer!(Payload!T))
+    {
+        ref inout(T) opUnary(string op)() inout
+        if (op == "*")
+        {
+            return *this.payload;
+        }
+    }
+
+    /**
+     * Returns: Whether this $(D_PSYMBOL Unique) holds some value.
+     */
+    @property bool isInitialized() const
+    {
+        return this.payload !is null;
+    }
+
+    ///
+    @nogc unittest
+    {
+        Unique!int u;
+        assert(!u.isInitialized);
+    }
+
+    /**
+     * Sets the internal pointer to $(D_KEYWORD). The allocator isn't changed.
+     *
+     * Returns: Reference to the owned object.
+     */
+    Payload!T release()
+    {
+        auto payload = this.payload;
+        this.payload = null;
+        return payload;
+    }
+
+    ///
+    @nogc unittest
+    {
+        auto u = defaultAllocator.unique!int(5);
+        assert(u.isInitialized);
+
+        auto i = u.release();
+        assert(*i == 5);
+        assert(!u.isInitialized);
+    }
+
+    mixin DefaultAllocator;
+    alias get this;
+}
+
+///
+@nogc unittest
+{
+    auto p = defaultAllocator.make!int(5);
+    auto s = Unique!int(p, defaultAllocator);
+    assert(*s == 5);
+}
+
+///
+@nogc unittest
+{
+    static bool destroyed = false;
+
+    struct F
+    {
+        ~this() @nogc
+        {
+            destroyed = true;
+        }
+    }
+    {
+        auto s = Unique!F(defaultAllocator.make!F(), defaultAllocator);
+    }
+    assert(destroyed);
+}
+
+/**
+ * Constructs a new object of type $(D_PARAM T) and wraps it in a
+ * $(D_PSYMBOL Unique) using $(D_PARAM args) as the parameter list for
+ * the constructor of $(D_PARAM T).
+ *
+ * Params:
+ *  T         = Type of the constructed object.
+ *  A         = Types of the arguments to the constructor of $(D_PARAM T).
+ *  allocator = Allocator.
+ *  args      = Constructor arguments of $(D_PARAM T).
+ * 
+ * Returns: Newly created $(D_PSYMBOL Unique!T).
+ *
+ * Precondition: $(D_INLINECODE allocator !is null)
+ */
+Unique!T unique(T, A...)(shared Allocator allocator, auto ref A args)
+if (!is(T == interface) && !isAbstractClass!T
+ && !isAssociativeArray!T && !isArray!T)
+in
+{
+    assert(allocator !is null);
+}
+body
+{
+    auto payload = allocator.make!(T, A)(args);
+    return Unique!T(payload, allocator);
+}
+
+/**
+ * Constructs a new array with $(D_PARAM size) elements and wraps it in a
+ * $(D_PSYMBOL Unique).
+ *
+ * Params:
+ *  T         = Array type.
+ *  size      = Array size.
+ *  allocator = Allocator.
+ *
+ * Returns: Newly created $(D_PSYMBOL Unique!T).
+ *
+ * Precondition: $(D_INLINECODE allocator !is null
+ *                           && size <= size_t.max / ElementType!T.sizeof)
+ */
+Unique!T unique(T)(shared Allocator allocator, const size_t size)
+@trusted
+if (isArray!T)
+in
+{
+    assert(allocator !is null);
+    assert(size <= size_t.max / ElementType!T.sizeof);
+}
+body
+{
+    auto payload = allocator.resize!(ElementType!T)(null, size);
+    return Unique!T(payload, allocator);
+}
+
+private unittest
+{
+    static assert(is(typeof(defaultAllocator.unique!B(5))));
+    static assert(is(typeof(defaultAllocator.unique!(int[])(5))));
+}
+
+private unittest
+{
+    auto s = defaultAllocator.unique!int(5);
+    assert(*s == 5);
+
+    s = null;
+    assert(s is null);
+}
+
+private unittest
+{
+    auto s = defaultAllocator.unique!int(5);
+    assert(*s == 5);
+
+    s = defaultAllocator.unique!int(4);
+    assert(*s == 4);
+}
+
+private @nogc unittest
+{
+    auto p1 = defaultAllocator.make!int(5);
+    auto p2 = p1;
+
+    auto rc = Unique!int(p1, defaultAllocator);
+    assert(rc.get() is p2);
+}
+
+private @nogc unittest
+{
+    auto rc = Unique!int(defaultAllocator);
+    assert(rc.allocator is defaultAllocator);
+}

source/tanya/memory/ullocator.d

@@ -1,423 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
- */  
-module tanya.memory.ullocator;
-
-import tanya.memory.allocator;
-
-@nogc:
-
-version (Posix):
-
-import core.sys.posix.sys.mman;
-import core.sys.posix.unistd;
-
-/**
- * Allocator for Posix systems with mmap/munmap support.
- *
- * This allocator allocates memory in regions (multiple of 4 KB for example).
- * Each region is then splitted in blocks. So it doesn't request the memory
- * from the operating system on each call, but only if there are no large
- * enought free blocks in the available regions.
- * Deallocation works in the same way. Deallocation doesn't immediately
- * gives the memory back to the operating system, but marks the appropriate
- * block as free and only if all blocks in the region are free, the complet
- * region is deallocated.
- *
- * ----------------------------------------------------------------------------
- * |      |     |         |     |            ||      |     |                  |
- * |      |prev <-----------    |            ||      |     |                  |
- * |  R   |  B  |         |  B  |            ||   R  |  B  |                  |
- * |  E   |  L  |         |  L  |           next  E  |  L  |                  |
- * |  G   |  O  |  DATA   |  O  |   FREE    --->  G  |  O  |       DATA       |
- * |  I   |  C  |         |  C  |           <---  I  |  C  |                  |
- * |  O   |  K  |         |  K  |           prev  O  |  K  |                  |
- * |  N   |    -----------> next|            ||   N  |     |                  |
- * |      |     |         |     |            ||      |     |                  |
- * --------------------------------------------------- ------------------------
- */
-class Ullocator : Allocator
-{
-@nogc:
-	@disable this();
-
-	shared static this() @safe nothrow
-	{
-		pageSize = sysconf(_SC_PAGE_SIZE);
-	}
-
-	/**
-	 * Allocates $(D_PARAM size) bytes of memory.
-	 *
-	 * Params:
-	 * 	size = Amount of memory to allocate.
-	 *
-	 * Returns: The pointer to the new allocated memory.
-	 */
-    void[] allocate(size_t size) @trusted nothrow
-    {
-		immutable dataSize = addAlignment(size);
-
-		void* data = findBlock(dataSize);
-		if (data is null)
-		{
-			data = initializeRegion(dataSize);
-		}
-
-		return data is null ? null : data[0..size];
-    }
-
-	///
-	unittest
-	{
-		auto p = Ullocator.instance.allocate(20);
-
-		assert(p);
-
-		Ullocator.instance.deallocate(p);
-	}
-
-	/**
-	 * Search for a block large enough to keep $(D_PARAM size) and split it
-	 * into two blocks if the block is too large.
-	 *
-	 * Params:
-	 * 	size = Minimum size the block should have.
-	 *
-	 * Returns: Data the block points to or $(D_KEYWORD null).
-	 */
-	private void* findBlock(size_t size) nothrow
-	{
-		Block block1;
-		RegionLoop: for (auto r = head; r !is null; r = r.next)
-		{
-			block1 = cast(Block) (cast(void*) r + regionEntrySize);
-			do
-			{
-				if (block1.free && block1.size >= size)
-				{
-					break RegionLoop;
-				}
-			}
-			while ((block1 = block1.next) !is null);
-		}
-		if (block1 is null)
-		{
-			return null;
-		}
-		else if (block1.size >= size + alignment + blockEntrySize)
-		{ // Split the block if needed
-			Block block2 = cast(Block) (cast(void*) block1 + blockEntrySize + size);
-			block2.prev = block1;
-			if (block1.next is null)
-			{
-				block2.next = null;
-			}
-			else
-			{
-				block2.next = block1.next.next;
-			}
-			block1.next = block2;
-
-			block1.free = false;
-			block2.free = true;
-
-			block2.size = block1.size - blockEntrySize - size;
-			block1.size = size;
-
-			block2.region = block1.region;
-			++block1.region.blocks;
-		}
-		else
-		{
-			block1.free = false;
-			++block1.region.blocks;
-		}
-		return cast(void*) block1 + blockEntrySize;
-	}
-
-    /**
-	 * Deallocates a memory block.
-	 *
-	 * Params:
-	 * 	p = A pointer to the memory block to be freed.
-	 *
-	 * Returns: Whether the deallocation was successful.
-	 */
-    bool deallocate(void[] p) @trusted nothrow
-    {
-		if (p is null)
-		{
-			return true;
-		}
-
-		Block block = cast(Block) (p.ptr - blockEntrySize);
-		if (block.region.blocks <= 1)
-		{
-			if (block.region.prev !is null)
-			{
-				block.region.prev.next = block.region.next;
-			}
-			else // Replace the list head. It is being deallocated
-			{
-				head = block.region.next;
-			}
-			if (block.region.next !is null)
-			{
-				block.region.next.prev = block.region.prev;
-			}
-			return munmap(block.region, block.region.size) == 0;
-		}
-		else
-		{
-			block.free = true;
-			--block.region.blocks;
-			return true;
-		}
-    }
-
-	///
-	unittest
-	{
-		auto p = Ullocator.instance.allocate(20);
-
-		assert(Ullocator.instance.deallocate(p));
-	}
-
-	/**
-	 * Increases or decreases the size of a memory block.
-	 *
-	 * Params:
-	 * 	p    = A pointer to the memory block.
-	 * 	size = Size of the reallocated block.
-	 *
-	 * Returns: Whether the reallocation was successful.
-	 */
-	bool reallocate(ref void[] p, size_t size) @trusted nothrow
-	{
-		if (size == p.length)
-		{
-			return true;
-		}
-
-		auto reallocP = allocate(size);
-		if (reallocP is null)
-		{
-			return false;
-		}
-
-		if (p !is null)
-		{
-			if (size > p.length)
-			{
-				reallocP[0..p.length] = p[0..$];
-			}
-			else
-			{
-				reallocP[0..size] = p[0..size];
-			}
-			deallocate(p);
-		}
-		p = reallocP;
-
-		return true;
-	}
-
-	///
-	unittest
-	{
-		void[] p;
-		Ullocator.instance.reallocate(p, 10 * int.sizeof);
-		(cast(int[]) p)[7] = 123;
-
-		assert(p.length == 40);
-
-		Ullocator.instance.reallocate(p, 8 * int.sizeof);
-
-		assert(p.length == 32);
-		assert((cast(int[]) p)[7] == 123);
-
-		Ullocator.instance.reallocate(p, 20 * int.sizeof);
-		(cast(int[]) p)[15] = 8;
-
-		assert(p.length == 80);
-		assert((cast(int[]) p)[15] == 8);
-		assert((cast(int[]) p)[7] == 123);
-
-		Ullocator.instance.reallocate(p, 8 * int.sizeof);
-
-		assert(p.length == 32);
-		assert((cast(int[]) p)[7] == 123);
-
-		Ullocator.instance.deallocate(p);
-	}
-
-	/**
-     * Static allocator instance and initializer.
-	 *
-	 * Returns: The global $(D_PSYMBOL Allocator) instance.
-	 */
-	static @property Ullocator instance() @trusted nothrow
-	{
-		if (instance_ is null)
-		{
-			immutable instanceSize = addAlignment(__traits(classInstanceSize, Ullocator));
-
-			Region head; // Will become soon our region list head
-			void* data = initializeRegion(instanceSize, head);
-
-			if (data is null)
-			{
-				return null;
-			}
-			data[0..instanceSize] = typeid(Ullocator).initializer[];
-			instance_ = cast(Ullocator) data;
-			instance_.head = head;
-		}
-		return instance_;
-	}
-
-	///
-	unittest
-	{
-		assert(instance is instance);
-	}
-
-	/**
-	 * Initializes a region for one element.
-	 *
-	 * Params:
-	 * 	size = Aligned size of the first data block in the region.
-	 *  head = Region list head.
-	 *
-	 * Returns: A pointer to the data.
-	 */
-	pragma(inline)
-	private static void* initializeRegion(size_t size,
-	                                      ref Region head) nothrow
-	{
-		immutable regionSize = calculateRegionSize(size);
-		void* p = mmap(null,
-		               regionSize,
-		               PROT_READ | PROT_WRITE,
-		               MAP_PRIVATE | MAP_ANON,
-		               -1,
-		               0);
-		if (p is MAP_FAILED)
-		{
-			return null;
-		}
-
-		Region region = cast(Region) p;
-		region.blocks = 1;
-		region.size = regionSize;
-
-		// Set the pointer to the head of the region list
-		if (head !is null)
-		{
-			head.prev = region;
-		}
-		region.next = head;
-		region.prev = null;
-		head = region;
-
-		// Initialize the data block
-		void* memoryPointer = p + regionEntrySize;
-		Block block1 = cast(Block) memoryPointer;
-		block1.size = size;
-		block1.free = false;
-
-		// It is what we want to return
-		void* data = memoryPointer + blockEntrySize;
-
-		// Free block after data
-		memoryPointer = data + size;
-		Block block2 = cast(Block) memoryPointer;
-		block1.prev = block2.next = null;
-		block1.next = block2;
-		block2.prev = block1;
-		block2.size = regionSize - size - regionEntrySize - blockEntrySize * 2;
-		block2.free = true;
-		block1.region = block2.region = region;
-
-		return data;
-	}
-
-	/// Ditto.
-	private void* initializeRegion(size_t size) nothrow
-	{
-		return initializeRegion(size, head);
-	}
-
-	/**
-	 * Params:
-	 * 	x = Space to be aligned.
-	 *
-	 * Returns: Aligned size of $(D_PARAM x).
-	 */
-	pragma(inline)
-	private static immutable(size_t) addAlignment(size_t x) @safe pure nothrow
-	out (result)
-	{
-		assert(result > 0);
-	}
-	body
-	{
-		return (x - 1) / alignment * alignment + alignment;
-	}
-
-	/**
-	 * Params:
-	 * 	x = Required space.
-	 *
-	 * Returns: Minimum region size (a multiple of $(D_PSYMBOL pageSize)).
-	 */
-	pragma(inline)
-	private static immutable(size_t) calculateRegionSize(size_t x)
-	@safe pure nothrow
-	out (result)
-	{
-		assert(result > 0);
-	}
-	body
-	{
-		x += regionEntrySize + blockEntrySize * 2;
-		return x / pageSize * pageSize + pageSize;
-	}
-
-	enum alignment = 8;
-
-	private static Ullocator instance_;
-
-	private shared static immutable long pageSize;
-
-	private struct RegionEntry
-	{
-		Region prev;
-		Region next;
-		uint blocks;
-		ulong size;
-	}
-	private alias Region = RegionEntry*;
-	private enum regionEntrySize = 32;
-
-	private Region head;
-
-	private struct BlockEntry
-	{
-		Block prev;
-		Block next;
-		bool free;
-		ulong size;
-		Region region;
-	}
-	private alias Block = BlockEntry*;
-	private enum blockEntrySize = 40;
-}

source/tanya/net/inet.d

@@ -0,0 +1,356 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Internet utilities.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.net.inet;
+
+import std.math;
+import std.range.primitives;
+import std.traits;
+
+version (unittest)
+{
+    version (Windows)
+    {
+        import core.sys.windows.winsock2;
+        version = PlattformUnittest;
+    }
+    else version (Posix)
+    {
+        import core.sys.posix.arpa.inet;
+        version = PlattformUnittest;
+    }
+}
+
+/**
+ * Represents an unsigned integer as an $(D_KEYWORD ubyte) range.
+ *
+ * The range is bidirectional. The byte order is always big-endian.
+ *
+ * It can accept any unsigned integral type but the value should fit
+ * in $(D_PARAM L) bytes.
+ *
+ * Params:
+ *  L = Desired range length.
+ */
+struct NetworkOrder(uint L)
+    if (L > ubyte.sizeof && L <= ulong.sizeof)
+{
+    static if (L > uint.sizeof)
+    {
+        private alias StorageType = ulong;
+    }
+    else static if (L > ushort.sizeof)
+    {
+        private alias StorageType = uint;
+    }
+    else static if (L > ubyte.sizeof)
+    {
+        private alias StorageType = ushort;
+    }
+    else
+    {
+        private alias StorageType = ubyte;
+    }
+
+    private StorageType value;
+    private size_t size = L;
+
+    const pure nothrow @safe @nogc invariant
+    {
+        assert(this.size <= L);
+    }
+
+    /**
+     * Constructs a new range.
+     *
+     * $(D_PARAM T) can be any unsigned type but $(D_PARAM value) cannot be
+     * larger than the maximum can be stored in $(D_PARAM L) bytes. Otherwise
+     * an assertion failure will be caused.
+     *
+     * Params:
+     *  T      = Value type.
+     *  value  = The value should be represented by this range.
+     *
+     * Precondition: $(D_INLINECODE value <= 2 ^^ (length * 8) - 1).
+     */
+    this(T)(const T value)
+        if (isUnsigned!T)
+    in
+    {
+        assert(value <= pow(2, L * 8) - 1);
+    }
+    body
+    {
+        this.value = value & StorageType.max;
+    }
+
+    /**
+     * Returns: LSB.
+     *
+     * Precondition: $(D_INLINECODE length > 0).
+     */
+    @property ubyte back() const
+    in
+    {
+        assert(this.length > 0);
+    }
+    body
+    {
+        return this.value & 0xff;
+    }
+
+    /**
+     * Returns: MSB.
+     *
+     * Precondition: $(D_INLINECODE length > 0).
+     */
+    @property ubyte front() const
+    in
+    {
+        assert(this.length > 0);
+    }
+    body
+    {
+        return (this.value >> ((this.length - 1) * 8)) & 0xff;
+    }
+
+    /**
+     * Eliminates the LSB.
+     *
+     * Precondition: $(D_INLINECODE length > 0).
+     */
+    void popBack()
+    in
+    {
+        assert(this.length > 0);
+    }
+    body
+    {
+        this.value >>= 8;
+        --this.size;
+    }
+
+    /**
+     * Eliminates the MSB.
+     *
+     * Precondition: $(D_INLINECODE length > 0).
+     */
+    void popFront()
+    in
+    {
+        assert(this.length > 0);
+    }
+    body
+    {
+        this.value &= StorageType.max >> ((StorageType.sizeof - this.length) * 8);
+        --this.size;
+    }
+
+    /**
+     * Returns: Copy of this range.
+     */
+    typeof(this) save() const
+    {
+        return this;
+    }
+
+    /**
+     * Returns: Whether the range is empty.
+     */
+    @property bool empty() const
+    {
+        return this.length == 0;
+    }
+
+    /**
+     * Returns: Byte length.
+     */
+    @property size_t length() const
+    {
+        return this.size;
+    }
+}
+
+///
+pure nothrow @safe @nogc unittest
+{
+    auto networkOrder = NetworkOrder!3(0xae34e2u);
+    assert(!networkOrder.empty);
+    assert(networkOrder.front == 0xae);
+
+    networkOrder.popFront();
+    assert(networkOrder.length == 2);
+    assert(networkOrder.front == 0x34);
+    assert(networkOrder.back == 0xe2);
+
+    networkOrder.popBack();
+    assert(networkOrder.length == 1);
+    assert(networkOrder.front == 0x34);
+    assert(networkOrder.front == 0x34);
+
+    networkOrder.popFront();
+    assert(networkOrder.empty);
+}
+
+// Static.
+private unittest
+{
+    static assert(isBidirectionalRange!(NetworkOrder!4));
+    static assert(isBidirectionalRange!(NetworkOrder!8));
+    static assert(!is(NetworkOrder!9));
+    static assert(!is(NetworkOrder!1));
+}
+
+// Tests against the system's htonl, htons.
+version (PlattformUnittest)
+{
+    private unittest
+    {
+        for (uint counter; counter <= 8 * uint.sizeof; ++counter)
+        {
+            const value = pow(2, counter) - 1;
+            const inNetworkOrder = htonl(value);
+            const p = cast(ubyte*) &inNetworkOrder;
+            auto networkOrder = NetworkOrder!4(value);
+
+            assert(networkOrder.length == 4);
+            assert(!networkOrder.empty);
+            assert(networkOrder.front == *p);
+            assert(networkOrder.back == *(p + 3));
+
+            networkOrder.popBack();
+            assert(networkOrder.length == 3);
+            assert(networkOrder.front == *p);
+            assert(networkOrder.back == *(p + 2));
+
+            networkOrder.popFront();
+            assert(networkOrder.length == 2);
+            assert(networkOrder.front == *(p + 1));
+            assert(networkOrder.back == *(p + 2));
+
+            networkOrder.popFront();
+            assert(networkOrder.length == 1);
+            assert(networkOrder.front == *(p + 2));
+            assert(networkOrder.back == *(p + 2));
+
+            networkOrder.popBack();
+            assert(networkOrder.length == 0);
+            assert(networkOrder.empty);
+        }
+
+        for (ushort counter; counter <= 8 * ushort.sizeof; ++counter)
+        {
+            const value = cast(ushort) (pow(2, counter) - 1);
+            const inNetworkOrder = htons(value);
+            const p = cast(ubyte*) &inNetworkOrder;
+
+            auto networkOrder = NetworkOrder!2(value);
+
+            assert(networkOrder.length == 2);
+            assert(!networkOrder.empty);
+            assert(networkOrder.front == *p);
+            assert(networkOrder.back == *(p + 1));
+
+            networkOrder.popBack();
+            assert(networkOrder.length == 1);
+            assert(networkOrder.front == *p);
+            assert(networkOrder.back == *p);
+
+            networkOrder.popBack();
+            assert(networkOrder.length == 0);
+            assert(networkOrder.empty);
+
+            networkOrder = NetworkOrder!2(value);
+
+            networkOrder.popFront();
+            assert(networkOrder.length == 1);
+            assert(networkOrder.front == *(p + 1));
+            assert(networkOrder.back == *(p + 1));
+
+            networkOrder.popFront();
+            assert(networkOrder.length == 0);
+            assert(networkOrder.empty);
+        }
+    }
+}
+
+/**
+ * Converts the $(D_KEYWORD ubyte) input range $(D_PARAM range) to
+ * $(D_PARAM T).
+ *
+ * The byte order of $(D_PARAM r) is assumed to be big-endian. The length
+ * cannot be larger than $(D_INLINECODE T.sizeof). Otherwise an assertion
+ * failure will be caused.
+ *
+ * Params:
+ *  T     = Desired return type.
+ *  R     = Range type.
+ *  range = Input range.
+ *
+ * Returns: Integral representation of $(D_PARAM range) with the host byte
+ *          order.
+ */
+T toHostOrder(T = size_t, R)(R range)
+    if (isInputRange!R
+     && !isInfinite!R
+     && is(Unqual!(ElementType!R) == ubyte)
+     && isUnsigned!T)
+{
+    T ret;
+    ushort pos = T.sizeof * 8;
+
+    for (; !range.empty && range.front == 0; pos -= 8, range.popFront())
+    {
+    }
+    for (; !range.empty; range.popFront())
+    {
+        assert(pos != 0);
+        pos -= 8;
+        ret |= (cast(T) range.front) << pos;
+    }
+
+    return ret >> pos;
+}
+
+///
+pure nothrow @safe @nogc unittest
+{
+    const value = 0xae34e2u;
+    auto networkOrder = NetworkOrder!4(value);
+    assert(networkOrder.toHostOrder() == value);
+}
+
+// Tests against the system's htonl, htons.
+version (PlattformUnittest)
+{
+    private unittest
+    {
+        for (uint counter; counter <= 8 * uint.sizeof; ++counter)
+        {
+            const value = pow(2, counter) - 1;
+            const inNetworkOrder = htonl(value);
+            const p = cast(ubyte*) &inNetworkOrder;
+            auto networkOrder = NetworkOrder!4(value);
+
+            assert(p[0 .. uint.sizeof].toHostOrder() == value);
+        }
+        for (ushort counter; counter <= 8 * ushort.sizeof; ++counter)
+        {
+            const value = cast(ushort) (pow(2, counter) - 1);
+            const inNetworkOrder = htons(value);
+            const p = cast(ubyte*) &inNetworkOrder;
+            auto networkOrder = NetworkOrder!2(value);
+
+            assert(p[0 .. ushort.sizeof].toHostOrder() == value);
+        }
+    }
+}

source/tanya/net/package.d

@@ -3,14 +3,14 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 /**
- * Copyright: Eugene Wissner 2016.
+ * Network programming.
+ *
+ * Copyright: Eugene Wissner 2017.
  * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
  *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
  */
-module tanya.event;
+module tanya.net;
 
-public import tanya.event.loop;
+public import tanya.net.inet;
-public import tanya.event.protocol;
+public import tanya.net.uri;
-public import tanya.event.transport;
-public import tanya.event.watcher;

source/tanya/net/uri.d

@@ -0,0 +1,573 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * URL parser.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.net.uri;
+
+import std.ascii : isAlphaNum, isDigit;
+import std.uni : isAlpha, isNumber;
+import tanya.memory;
+
+/**
+ * Thrown if an invalid URI was specified.
+ */
+final class URIException : Exception
+{
+    /**
+     * Params:
+     *  msg  = The message for the exception.
+     *  file = The file where the exception occurred.
+     *  line = The line number where the exception occurred.
+     *  next = The previous exception in the chain of exceptions, if any.
+     */
+    this(string msg,
+         string file = __FILE__,
+         size_t line = __LINE__,
+         Throwable next = null) @nogc @safe pure nothrow
+    {
+        super(msg, file, line, next);
+    }
+}
+
+/**
+ * A Unique Resource Locator.
+ */
+struct URL
+{
+    /// The URL scheme.
+    const(char)[] scheme;
+
+    /// The username.
+    const(char)[] user;
+
+    /// The password.
+    const(char)[] pass;
+
+    /// The hostname.
+    const(char)[] host;
+
+    /// The port number.
+    ushort port;
+
+    /// The path.
+    const(char)[] path;
+
+    /// The query string.
+    const(char)[] query;
+
+    /// The anchor.
+    const(char)[] fragment;
+
+    /**
+     * Attempts to parse an URL from a string.
+     * Output string data (scheme, user, etc.) are just slices of input string
+     * (i.e., no memory allocation and copying).
+     *
+     * Params:
+     *  source = The string containing the URL.
+     *
+     * Throws: $(D_PSYMBOL URIException) if the URL is malformed.
+     */
+    this(const char[] source) pure @nogc
+    {
+        ptrdiff_t pos = -1, endPos = source.length, start;
+
+        foreach (i, ref c; source)
+        {
+            if (pos == -1 && c == ':')
+            {
+                pos = i;
+            }
+            if (endPos == source.length && (c == '?' || c == '#'))
+            {
+                endPos = i;
+            }
+        }
+
+        // Check if the colon is a part of the scheme or the port and parse
+        // the appropriate part.
+        if (source.length > 1 && source[0] == '/' && source[1] == '/')
+        {
+            // Relative scheme.
+            start = 2;
+        }
+        else if (pos > 0)
+        {
+            // Validate scheme:
+            // [ toLower(alpha) | digit | "+" | "-" | "." ]
+            foreach (ref c; source[0 .. pos])
+            {
+                if (!c.isAlphaNum && c != '+' && c != '-' && c != '.')
+                {
+                    goto ParsePath;
+                }
+            }
+
+            if (source.length == pos + 1) // only "scheme:" is available.
+            {
+                this.scheme = source[0 .. $ - 1];
+                return;
+            }
+            else if (source.length > pos + 1 && source[pos + 1] == '/')
+            {
+                this.scheme = source[0 .. pos];
+
+                if (source.length > pos + 2 && source[pos + 2] == '/')
+                {
+                    start = pos + 3;
+
+                    if (source.length <= start)
+                    {
+                        // Only "scheme://" is available.
+                        return;
+                    }
+                    if (this.scheme == "file" && source[start] == '/')
+                    {
+                        // Windows drive letters.
+                        if (source.length - start > 2
+                         && source[start + 2] == ':')
+                        {
+                            ++start;
+                        }
+                        goto ParsePath;
+                    }
+                }
+                else
+                {
+                    start = pos + 1;
+                    goto ParsePath;
+                }
+            }
+            else
+            {
+                // Schemas like mailto: and zlib: may not have any slash after
+                // them.
+                if (!parsePort(source[pos .. $]))
+                {
+                    this.scheme = source[0 .. pos];
+                    start = pos + 1;
+                    goto ParsePath;
+                }
+            }
+        }
+        else if (pos == 0 && parsePort(source[pos .. $]))
+        {
+            // An URL shouldn't begin with a port number.
+            throw defaultAllocator.make!URIException("URL begins with port");
+        }
+        else
+        {
+            goto ParsePath;
+        }
+
+        // Parse host.
+        pos = -1;
+        for (ptrdiff_t i = start; i < source.length; ++i)
+        {
+            if (source[i] == '@')
+            {
+                pos = i;
+            }
+            else if (source[i] == '/')
+            {
+                endPos = i;
+                break;
+            }
+        }
+
+        // Check for login and password.
+        if (pos != -1)
+        {
+            // *( unreserved / pct-encoded / sub-delims / ":" )
+            foreach (i, c; source[start .. pos])
+            {
+                if (c == ':')
+                {
+                    if (this.user is null)
+                    {
+                        this.user = source[start .. start + i];
+                        this.pass = source[start + i + 1 .. pos]; 
+                    }
+                }
+                else if (!c.isAlpha &&
+                         !c.isNumber &&
+                         c != '!' &&
+                         c != ';' &&
+                         c != '=' &&
+                         c != '_' &&
+                         c != '~' &&
+                         !(c >= '$' && c <= '.'))
+                {
+                    this.scheme = this.user = this.pass = null;
+                    throw make!URIException(defaultAllocator,
+                                            "Restricted characters in user information");
+                }
+            }
+            if (this.user is null)
+            {
+                this.user = source[start .. pos];
+            }
+
+            start = ++pos;
+        }
+
+        pos = endPos;
+        if (endPos <= 1 || source[start] != '[' || source[endPos - 1] != ']')
+        {
+            // Short circuit portscan.
+            // IPv6 embedded address.
+            for (ptrdiff_t i = endPos - 1; i >= start; --i)
+            {
+                if (source[i] == ':')
+                {
+                    pos = i;
+                    if  (this.port == 0 && !parsePort(source[i .. endPos]))
+                    {
+                        this.scheme = this.user = this.pass = null;
+                        throw defaultAllocator.make!URIException("Invalid port");
+                    }
+                    break;
+                }
+            }
+        }
+
+        // Check if we have a valid host, if we don't reject the string as URL.
+        if (pos <= start)
+        {
+            this.scheme = this.user = this.pass = null;
+            throw defaultAllocator.make!URIException("Invalid host");
+        }
+
+        this.host = source[start .. pos];
+
+        if (endPos == source.length)
+        {
+            return;
+        }
+
+        start = endPos;
+
+    ParsePath:
+        endPos = source.length;
+        pos = -1;
+        foreach (i, ref c; source[start .. $])
+        {
+            if (c == '?' && pos == -1)
+            {
+                pos = start + i;
+            }
+            else if (c == '#')
+            {
+                endPos = start + i;
+                break;
+            }
+        }
+        if (pos == -1)
+        {
+            pos = endPos;
+        }
+
+        if (pos > start)
+        {
+            this.path = source[start .. pos];
+        }
+        if (endPos >= ++pos)
+        {
+            this.query = source[pos .. endPos];
+        }
+        if (++endPos <= source.length)
+        {
+            this.fragment = source[endPos .. $];
+        }
+    }
+
+    /*
+     * Attempts to parse and set the port.
+     *
+     * Params:
+     *  port = String beginning with a colon followed by the port number and
+     *         an optional path (query string and/or fragment), like:
+     *         `:12345/some_path` or `:12345`.
+     *
+     * Returns: Whether the port could be found.
+     */
+    private bool parsePort(const char[] port) pure nothrow @safe @nogc
+    {
+        ptrdiff_t i = 1;
+        float lPort = 0;
+
+        for (; i < port.length && port[i].isDigit() && i <= 6; ++i)
+        {
+            lPort += (port[i] - '0') / cast(float) (10 ^^ (i - 1));
+        }
+        if (i != 1 && (i == port.length || port[i] == '/'))
+        {
+            lPort *= 10 ^^ (i - 2);
+            if (lPort > ushort.max)
+            {
+                return false;
+            }
+            this.port = cast(ushort) lPort;
+            return true;
+        }
+        return false;
+    }
+}
+
+///
+@nogc unittest
+{
+    auto u = URL("example.org");
+    assert(u.path == "example.org"); 
+
+    u = URL("relative/path");
+    assert(u.path == "relative/path"); 
+
+    // Host and scheme
+    u = URL("https://example.org");
+    assert(u.scheme == "https");
+    assert(u.host == "example.org");
+    assert(u.path is null);
+    assert(u.port == 0);
+    assert(u.fragment is null);
+
+    // With user and port and path
+    u = URL("https://hilary:putnam@example.org:443/foo/bar");
+    assert(u.scheme == "https");
+    assert(u.host == "example.org");
+    assert(u.path == "/foo/bar");
+    assert(u.port == 443);
+    assert(u.user == "hilary");
+    assert(u.pass == "putnam");
+    assert(u.fragment is null);
+
+    // With query string
+    u = URL("https://example.org/?login=true");
+    assert(u.scheme == "https");
+    assert(u.host == "example.org");
+    assert(u.path == "/");
+    assert(u.query == "login=true");
+    assert(u.fragment is null);
+
+    // With query string and fragment
+    u = URL("https://example.org/?login=false#label");
+    assert(u.scheme == "https");
+    assert(u.host == "example.org");
+    assert(u.path == "/");
+    assert(u.query == "login=false");
+    assert(u.fragment == "label");
+
+    u = URL("redis://root:password@localhost:2201/path?query=value#fragment");
+    assert(u.scheme == "redis");
+    assert(u.user == "root");
+    assert(u.pass == "password");
+    assert(u.host == "localhost");
+    assert(u.port == 2201);
+    assert(u.path == "/path");
+    assert(u.query == "query=value");
+    assert(u.fragment == "fragment");
+}
+
+private @nogc unittest
+{
+    auto u = URL("127.0.0.1");
+    assert(u.path == "127.0.0.1");
+
+    u = URL("http://127.0.0.1");
+    assert(u.scheme == "http");
+    assert(u.host == "127.0.0.1");
+
+    u = URL("http://127.0.0.1:9000");
+    assert(u.scheme == "http");
+    assert(u.host == "127.0.0.1");
+    assert(u.port == 9000);
+
+    u = URL("127.0.0.1:80");
+    assert(u.host == "127.0.0.1");
+    assert(u.port == 80);
+    assert(u.path is null);
+
+    u = URL("//example.net");
+    assert(u.host == "example.net");
+    assert(u.scheme is null);
+
+    u = URL("//example.net?q=before:after");
+    assert(u.host == "example.net");
+    assert(u.query == "q=before:after");
+
+    u = URL("localhost:8080");
+    assert(u.host == "localhost");
+    assert(u.port == 8080);
+    assert(u.path is null);
+
+    u = URL("ftp:");
+    assert(u.scheme == "ftp");
+
+    u = URL("file:///C:\\Users");
+    assert(u.scheme == "file");
+    assert(u.path == "C:\\Users");
+
+    u = URL("localhost:66000");
+    assert(u.scheme == "localhost");
+    assert(u.path == "66000");
+
+    u = URL("file:///home/");
+    assert(u.scheme == "file");
+    assert(u.path == "/home/");
+
+    u = URL("file:///home/?q=asdf");
+    assert(u.scheme == "file");
+    assert(u.path == "/home/");
+    assert(u.query == "q=asdf");
+
+    u = URL("http://secret@example.org");
+    assert(u.scheme == "http");
+    assert(u.host == "example.org");
+    assert(u.user == "secret");
+
+    u = URL("h_tp://:80");
+    assert(u.path == "h_tp://:80");
+    assert(u.port == 0);
+
+    u = URL("zlib:/home/user/file.gz");
+    assert(u.scheme == "zlib");
+    assert(u.path == "/home/user/file.gz");
+
+    u = URL("h_tp:asdf");
+    assert(u.path == "h_tp:asdf");
+}
+
+private @nogc unittest
+{
+    URIException exception;
+    try
+    {
+        auto u = URL("http://:80");
+    }
+    catch (URIException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    URIException exception;
+    try
+    {
+        auto u = URL(":80");
+    }
+    catch (URIException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    URIException exception;
+    try
+    {
+        auto u = URL("http://user1:pass1@user2:pass2@example.org");
+    }
+    catch (URIException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    URIException exception;
+    try
+    {
+        auto u = URL("http://blah.com:port");
+    }
+    catch (URIException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+private @nogc unittest
+{
+    URIException exception;
+    try
+    {
+        auto u = URL("http://blah.com:66000");
+    }
+    catch (URIException e)
+    {
+        exception = e;
+    }
+    assert(exception !is null);
+    defaultAllocator.dispose(exception);
+}
+
+// Issue 254: https://issues.caraus.io/issues/254.
+private @system @nogc unittest
+{
+    auto u = URL("ftp://");
+    assert(u.scheme == "ftp");
+}
+
+/**
+ * Attempts to parse an URL from a string and returns the specified component
+ * of the URL or $(D_PSYMBOL URL) if no component is specified.
+ *
+ * Params:
+ *  T      = "scheme", "host", "port", "user", "pass", "path", "query",
+ *           "fragment".
+ *  source = The string containing the URL.
+ *
+ * Returns: Requested URL component.
+ */
+auto parseURL(string T)(const char[] source)
+if (T == "scheme"
+ || T == "host"
+ || T == "user"
+ || T == "pass"
+ || T == "path"
+ || T == "query"
+ || T == "fragment"
+ || T == "port")
+{
+    auto ret = URL(source);
+    return mixin("ret." ~ T);
+}
+
+/// Ditto.
+URL parseURL(const char[] source) @nogc
+{
+    return URL(source);
+}
+
+///
+@nogc unittest
+{
+    auto u = parseURL("http://example.org:5326");
+    assert(u.scheme == parseURL!"scheme"("http://example.org:5326"));
+    assert(u.host == parseURL!"host"("http://example.org:5326"));
+    assert(u.user == parseURL!"user"("http://example.org:5326"));
+    assert(u.pass == parseURL!"pass"("http://example.org:5326"));
+    assert(u.path == parseURL!"path"("http://example.org:5326"));
+    assert(u.query == parseURL!"query"("http://example.org:5326"));
+    assert(u.fragment == parseURL!"fragment"("http://example.org:5326"));
+    assert(u.port == parseURL!"port"("http://example.org:5326"));
+}

source/tanya/network/package.d

@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Network programming.
+ *
+ * Copyright: Eugene Wissner 2016-2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.network;
+
+public import tanya.network.socket;

source/tanya/os/error.d

@@ -0,0 +1,337 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This module provides a portable way of using operating system error codes.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.os.error;
+
+// Socket API error.
+private template SAError(int posix, int wsa = posix)
+{
+    version (Windows)
+    {
+        enum SAError = 10000 + wsa;
+    }
+    else
+    {
+        alias SAError = posix;
+    }
+}
+
+// Error for Windows and Posix separately.
+private template NativeError(int posix, int win)
+{
+    version (Windows)
+    {
+        alias NativeError = win;
+    }
+    else
+    {
+        alias NativeError = posix;
+    }
+}
+
+version (Windows)
+{
+    private enum eProtocolError = -71;
+}
+else version (OpenBSD)
+{
+    private enum eProtocolError = -71;
+}
+else
+{
+    private enum eProtocolError = 71;
+}
+
+/**
+ * System error code.
+ */
+struct ErrorCode
+{
+    /**
+     * Error code numbers.
+     */
+    enum ErrorNo : int
+    {
+        /// The operation completed successfully.
+        success                   = 0,
+
+        /// Operation not permitted.
+        noPermission              = NativeError!(1, 5),
+
+        /// Interrupted system call.
+        interrupted               = SAError!4,
+
+        /// Bad file descriptor.
+        badDescriptor             = SAError!9,
+
+        /// An operation on a non-blocking socket would block.
+        wouldBlock                = SAError!(11, 35),
+
+        /// Out of memory.
+        noMemory                  = NativeError!(12, 14),
+
+        /// Access denied.
+        accessDenied              = SAError!13,
+
+        /// An invalid pointer address detected.
+        fault                     = SAError!14,
+
+        /// No such device.
+        noSuchDevice              = NativeError!(19, 20),
+
+        /// An invalid argument was supplied.
+        invalidArgument           = SAError!22,
+
+        /// The limit on the number of open file descriptors.
+        tooManyDescriptors        = NativeError!(23, 331),
+
+        /// The limit on the number of open file descriptors.
+        noDescriptors             = SAError!24,
+
+        /// Broken pipe.
+        brokenPipe                = NativeError!(32, 109),
+
+        /// The name was too long.
+        nameTooLong               = SAError!(36, 63),
+
+        /// A socket operation was attempted on a non-socket.
+        notSocket                 = SAError!(88, 38),
+
+        /// Protocol error.
+        protocolError             = eProtocolError,
+
+        /// Message too long.
+        messageTooLong            = SAError!(90, 40),
+
+        /// Wrong protocol type for socket.
+        wrongProtocolType         = SAError!(91, 41),
+
+        /// Protocol not available.
+        noProtocolOption          = SAError!(92, 42),
+
+        /// The protocol is not implemented orR has not been configured.
+        protocolNotSupported      = SAError!(93, 43),
+
+        /// The support for the specified socket type does not exist in this
+        /// address family.
+        socketNotSupported        = SAError!(94, 44),
+
+        /// The address family is no supported by the protocol family.
+        operationNotSupported     = SAError!(95, 45),
+
+        /// Address family specified is not supported.
+        addressFamilyNotSupported = SAError!(97, 47),
+
+        /// Address already in use.
+        addressInUse              = SAError!(98, 48),
+
+        /// The network is not available.
+        networkDown               = SAError!(100, 50),
+
+        /// No route to host.
+        networkUnreachable        = SAError!(101, 51),
+
+        /// Network dropped connection because of reset.
+        networkReset              = SAError!(102, 52),
+
+        /// The connection has been aborted.
+        connectionAborted         = SAError!(103, 53),
+
+        /// Connection reset by peer.
+        connectionReset           = SAError!(104, 54),
+
+        /// No free buffer space is available for a socket operation.
+        noBufferSpace             = SAError!(105, 55),
+
+        /// Transport endpoint is already connected.
+        alreadyConnected          = SAError!(106, 56),
+
+        /// Transport endpoint is not connected.
+        notConnected              = SAError!(107, 57),
+
+        /// Cannot send after transport endpoint shutdown.
+        shutdown                  = SAError!(108, 58),
+
+        /// The connection attempt timed out, or the connected host has failed
+        /// to respond.
+        timedOut                  = SAError!(110, 60),
+
+        /// Connection refused.
+        connectionRefused         = SAError!(111, 61),
+
+        /// Host is down.
+        hostDown                  = SAError!(112, 64),
+
+        /// No route to host.
+        hostUnreachable           = SAError!(113, 65),
+
+        /// Operation already in progress.
+        alreadyStarted            = SAError!(114, 37),
+
+        /// Operation now in progress.
+        inProgress                = SAError!(115, 36),
+
+        /// Operation cancelled.
+        cancelled                 = SAError!(125, 103),
+    }
+
+    /**
+     * Constructor.
+     *
+     * Params:
+     *  value = Numeric error code.
+     */
+    this(const ErrorNo value) pure nothrow @safe @nogc
+    {
+        this.value_ = value;
+    }
+
+    ///
+    pure nothrow @safe @nogc unittest
+    {
+        ErrorCode ec;
+        assert(ec == ErrorCode.success);
+
+        ec = ErrorCode.fault;
+        assert(ec == ErrorCode.fault);
+    }
+
+    /**
+     * Resets this $(D_PSYMBOL ErrorCode) to default
+     * ($(D_PSYMBOL ErrorCode.success)).
+     */
+    void reset() pure nothrow @safe @nogc
+    {
+        this.value_ = ErrorNo.success;
+    }
+
+    ///
+    pure nothrow @safe @nogc unittest
+    {
+        auto ec = ErrorCode(ErrorCode.fault);
+        assert(ec == ErrorCode.fault);
+
+        ec.reset();
+        assert(ec == ErrorCode.success);
+    }
+
+    /**
+     * Returns: Numeric error code.
+     */
+    ErrorNo opCast(T : ErrorNo)() const
+    {
+        return this.value_;
+    }
+
+    /// Ditto.
+    ErrorNo opCast(T : int)() const
+    {
+        return this.value_;
+    }
+
+    ///
+    pure nothrow @safe @nogc unittest
+    {
+        ErrorCode ec = ErrorCode.fault;
+        auto errorNo = cast(ErrorCode.ErrorNo) ec;
+
+        assert(errorNo == ErrorCode.fault);
+        static assert(is(typeof(cast(int) ec)));
+    }
+
+    /**
+     * Assigns another error code or error code number.
+     *
+     * Params:
+     *  that = Numeric error code.
+     *
+     * Returns: $(D_KEYWORD this).
+     */
+    ref ErrorCode opAssign(const ErrorNo that) pure nothrow @safe @nogc
+    {
+        this.value_ = that;
+        return this;
+    }
+
+    /// Ditto.
+    ref ErrorCode opAssign()(auto ref const ErrorCode that)
+    pure nothrow @safe @nogc
+    {
+        this.value_ = that.value_;
+        return this;
+    }
+
+    ///
+    pure nothrow @safe @nogc unittest
+    {
+        {
+            ErrorCode ec;
+            assert(ec == ErrorCode.success);
+
+            ec = ErrorCode.fault;
+            assert(ec == ErrorCode.fault);
+        }
+        {
+            auto ec1 = ErrorCode(ErrorCode.fault);
+            ErrorCode ec2;
+            assert(ec2 == ErrorCode.success);
+
+            ec2 = ec1;
+            assert(ec1 == ec2);
+        }
+    }
+
+    /**
+     * Equality with another error code or error code number.
+     *
+     * Params:
+     *  that = Numeric error code.
+     *
+     * Returns: Whether $(D_KEYWORD this) and $(D_PARAM that) are equal.
+     */
+    bool opEquals(const ErrorNo that) const pure nothrow @safe @nogc
+    {
+        return this.value_ == that;
+    }
+
+    /// Ditto.
+    bool opEquals()(auto ref const ErrorCode that)
+    const pure nothrow @safe @nogc
+    {
+        return this.value_ == that.value_;
+    }
+
+    ///
+    pure nothrow @safe @nogc unittest
+    {
+        {
+            ErrorCode ec1 = ErrorCode.fault;
+            ErrorCode ec2 = ErrorCode.accessDenied;
+
+            assert(ec1 != ec2);
+            assert(ec1 != ErrorCode.accessDenied);
+            assert(ErrorCode.fault != ec2);
+        }
+        {
+            ErrorCode ec1 = ErrorCode.fault;
+            ErrorCode ec2 = ErrorCode.fault;
+
+            assert(ec1 == ec2);
+            assert(ec1 == ErrorCode.fault);
+            assert(ErrorCode.fault == ec2);
+        }
+    }
+
+    private ErrorNo value_ = ErrorNo.success;
+
+    alias ErrorNo this;
+}

source/tanya/os/package.d

@@ -0,0 +1,16 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This package provides platform-independent interfaces to operating system
+ * functionality.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.os;
+
+public import tanya.os.error;

source/tanya/random.d

@@ -1,324 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-/**
- * Copyright: Eugene Wissner 2016.
- * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
- *                  Mozilla Public License, v. 2.0).
- * Authors: $(LINK2 mailto:belka@caraus.de, Eugene Wissner)
- */  
-module tanya.random;
-
-import tanya.memory;
-import std.digest.sha;
-import std.typecons;
-
-@nogc:
-
-/// Block size of entropy accumulator (SHA-512).
-enum blockSize = 64;
-
-/// Maximum amount gathered from the entropy sources.
-enum maxGather = 128;
-
-/**
- * Exception thrown if random number generating fails.
- */
-class EntropyException : Exception
-{
-@nogc:
-	/**
-	 * Params:
-	 * 	msg  = Message to output.
-	 * 	file = The file where the exception occurred.
-	 * 	line = The line number where the exception occurred.
-	 * 	next = The previous exception in the chain of exceptions, if any.
-	 */
-	this(string msg,
-	     string file = __FILE__,
-	     size_t line = __LINE__,
-	     Throwable next = null) pure @safe nothrow const
-	{
-		super(msg, file, line, next);
-	}
-}
-
-/**
- * Interface for implementing entropy sources.
- */
-abstract class EntropySource
-{
-@nogc:
-	/// Amount of already generated entropy.
-	protected ushort size_;
-
-	/**
-	 * Returns: Minimum bytes required from the entropy source.
-	 */
-	@property immutable(ubyte) threshold() const @safe pure nothrow;
-
-	/**
-	 * Returns: Whether this entropy source is strong.
-	 */
-	@property immutable(bool) strong() const @safe pure nothrow;
-
-	/**
-	 * Returns: Amount of already generated entropy.
-	 */
-	@property ushort size() const @safe pure nothrow
-	{
-		return size_;
-	}
-
-	/**
-	 * Params:
-	 * 	size = Amount of already generated entropy. Cannot be smaller than the
-	 * 	       already set value.
-	 */
-	@property void size(ushort size) @safe pure nothrow
-	{
-		size_ = size;
-	}
-
-	/**
-	 * Poll the entropy source.
-	 *
-	 * Params:
-	 * 	output = Buffer to save the generate random sequence (the method will
-	 * 	         to fill the buffer).
-	 *
-	 * Returns: Number of bytes that were copied to the $(D_PARAM output)
-	 *          or $(D_PSYMBOL Nullable!ubyte.init) on error.
-	 */
-	Nullable!ubyte poll(out ubyte[maxGather] output);
-}
-
-version (linux)
-{
-	extern (C) long syscall(long number, ...) nothrow;
-
-	/**
-	 * Uses getrandom system call.
-	 */
-	class PlatformEntropySource : EntropySource
-	{
-	@nogc:
-		/**
-		 * Returns: Minimum bytes required from the entropy source.
-		 */
-		override @property immutable(ubyte) threshold() const @safe pure nothrow
-		{
-			return 32;
-		}
-
-		/**
-		 * Returns: Whether this entropy source is strong.
-		 */
-		override @property immutable(bool) strong() const @safe pure nothrow
-		{
-			return true;
-		}
-
-		/**
-		 * Poll the entropy source.
-		 *
-		 * Params:
-		 * 	output = Buffer to save the generate random sequence (the method will
-		 * 	         to fill the buffer).
-		 *
-		 * Returns: Number of bytes that were copied to the $(D_PARAM output)
-		 *          or $(D_PSYMBOL Nullable!ubyte.init) on error.
-		 */
-		override Nullable!ubyte poll(out ubyte[maxGather] output) nothrow
-		out (length)
-		{
-			assert(length <= maxGather);
-		}
-		body
-		{
-			// int getrandom(void *buf, size_t buflen, unsigned int flags);
-			auto length = syscall(318, output.ptr, output.length, 0);
-			Nullable!ubyte ret;
-
-			if (length >= 0)
-			{
-				ret = cast(ubyte) length;
-			}
-			return ret;
-		}
-	}
-}
-
-/**
- * Pseudorandom number generator.
- * ---
- * auto entropy = defaultAllocator.make!Entropy;
- *
- * ubyte[blockSize] output;
- *
- * output = entropy.random;
- *
- * defaultAllocator.finalize(entropy);
- * ---
- */
-class Entropy
-{
-@nogc:
-	/// Entropy sources.
-	protected EntropySource[] sources;
-
-	private ubyte sourceCount_;
-
-	private Allocator allocator;
-
-	/// Entropy accumulator.
-	protected SHA!(maxGather * 8, 512) accumulator;
-
-	/**
-	 * Params:
-	 *  maxSources = Maximum amount of entropy sources can be set.
-	 * 	allocator  = Allocator to allocate entropy sources available on the
-	 * 	             system.
-	 */
-	this(size_t maxSources = 20, Allocator allocator = defaultAllocator)
-	in
-	{
-		assert(maxSources > 0 && maxSources <= ubyte.max);
-		assert(allocator !is null);
-	}
-	body
-	{
-		allocator.resizeArray(sources, maxSources);
-
-		version (linux)
-		{
-			this ~= allocator.make!PlatformEntropySource;
-		}
-	}
-
-	/**
-	 * Returns: Amount of the registered entropy sources.
-	 */
-	@property ubyte sourceCount() const @safe pure nothrow
-	{
-		return sourceCount_;
-	}
-
-	/**
-	 * Add an entropy source.
-	 *
-	 * Params:
-	 * 	source = Entropy source.
-	 *
-	 * Returns: $(D_PSYMBOL this).
-	 *
-	 * See_Also:
-	 * 	$(D_PSYMBOL EntropySource)
-	 */
-	Entropy opOpAssign(string Op)(EntropySource source) @safe pure nothrow
-		if (Op == "~")
-	in
-	{
-		assert(sourceCount_ <= sources.length);
-	}
-	body
-	{
-		sources[sourceCount_++] = source;
-		return this;
-	}
-
-	/**
-	 * Returns: Generated random sequence.
-	 *
-	 * Throws: $(D_PSYMBOL EntropyException) if no strong entropy source was
-	 *         registered or it failed.
-	 */
-	@property ubyte[blockSize] random()
-	in
-	{
-		assert(sourceCount_ > 0, "No entropy sources defined.");
-	}
-	body
-	{
-		bool haveStrong;
-		ushort done;
-		ubyte[blockSize] output;
-
-		do
-		{
-			ubyte[maxGather] buffer;
-
-			// Run through our entropy sources
-			for (ubyte i; i < sourceCount; ++i)
-			{
-				auto outputLength = sources[i].poll(buffer);
-
-				if (!outputLength.isNull)
-				{
-					if (outputLength > 0)
-					{
-						update(i, buffer, outputLength);
-						sources[i].size = cast(ushort) (sources[i].size + outputLength);
-					}
-					if (sources[i].size < sources[i].threshold)
-					{
-						continue;
-					}
-					else if (sources[i].strong)
-					{
-						haveStrong = true;
-					}
-				}
-				done = 257;
-			}
-		}
-		while (++done < 256);
-
-		if (!haveStrong)
-		{
-			throw allocator.make!EntropyException("No strong entropy source defined.");
-		}
-
-		output = accumulator.finish();
-
-		// Reset accumulator and counters and recycle existing entropy
-		accumulator.start();
-
-		// Perform second SHA-512 on entropy
-		output = sha512Of(output);
-
-		for (ubyte i = 0; i < sourceCount; ++i)
-		{
-			sources[i].size = 0;
-		}
-		return output;
-	}
-
-	/**
-	 * Update entropy accumulator.
-	 *
-	 * Params:
-	 * 	sourceId = Entropy source index in $(D_PSYMBOL sources).
-	 * 	data     = Data got from the entropy source.
-	 * 	length   = Length of the received data.
-	 */
-	protected void update(in ubyte sourceId,
-	                      ref ubyte[maxGather] data,
-	                      ubyte length) @safe pure nothrow
-	{
-		ubyte[2] header;
-
-		if (length > blockSize)
-		{
-			data[0..64] = sha512Of(data);
-			length = blockSize;
-		}
-
-		header[0] = sourceId;
-		header[1] = length;
-
-		accumulator.put(header);
-		accumulator.put(data[0..length]);
-	}
-}

source/tanya/typecons.d

@@ -0,0 +1,107 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Type constructors.
+ *
+ * This module contains templates that allow to build new types from the
+ * available ones.
+ *
+ * Copyright: Eugene Wissner 2017.
+ * License: $(LINK2 https://www.mozilla.org/en-US/MPL/2.0/,
+ *                  Mozilla Public License, v. 2.0).
+ * Authors: $(LINK2 mailto:info@caraus.de, Eugene Wissner)
+ */
+module tanya.typecons;
+
+import std.meta;
+
+/**
+ * $(D_PSYMBOL Pair) can store two heterogeneous objects.
+ *
+ * The objects can by accessed by index as $(D_INLINECODE obj[0]) and
+ * $(D_INLINECODE obj[1]) or by optional names (e.g.
+ * $(D_INLINECODE obj.first)).
+ *
+ * $(D_PARAM Specs) contains a list of object types and names. First
+ * comes the object type, then an optional string containing the name.
+ * If you want the object be accessible only by its index (`0` or `1`),
+ * just skip the name.
+ *
+ * Params:
+ *  Specs = Field types and names.
+ */
+template Pair(Specs...)
+{
+    template parseSpecs(int fieldCount, Specs...)
+    {
+        static if (Specs.length == 0)
+        {
+            alias parseSpecs = AliasSeq!();
+        }
+        else static if (is(Specs[0]) && fieldCount < 2)
+        {
+            static if (is(typeof(Specs[1]) == string))
+            {
+                alias parseSpecs
+                    = AliasSeq!(Specs[0],
+                                parseSpecs!(fieldCount + 1, Specs[2 .. $]));
+            }
+            else
+            {
+                alias parseSpecs
+                    = AliasSeq!(Specs[0],
+                                parseSpecs!(fieldCount + 1, Specs[1 .. $]));
+            }
+        }
+        else
+        {
+            static assert(false, "Invalid argument: " ~ Specs[0].stringof);
+        }
+    }
+
+    struct Pair
+    {
+        /// Field types.
+        alias Types = parseSpecs!(0, Specs);
+
+        static assert(Types.length == 2, "Invalid argument count.");
+
+        // Create field aliases.
+        static if (is(typeof(Specs[1]) == string))
+        {
+            mixin("alias " ~ Specs[1] ~ " = expand[0];");
+        }
+        static if (is(typeof(Specs[2]) == string))
+        {
+            mixin("alias " ~ Specs[2] ~ " = expand[1];");
+        }
+        else static if (is(typeof(Specs[3]) == string))
+        {
+            mixin("alias " ~ Specs[3] ~ " = expand[1];");
+        }
+
+        /// Represents the values of the $(D_PSYMBOL Pair) as a list of values.
+        Types expand;
+
+        alias expand this;
+    }
+}
+
+///
+unittest
+{
+    static assert(is(Pair!(int, int)));
+    static assert(!is(Pair!(int, 5)));
+
+    static assert(is(Pair!(int, "first", int)));
+    static assert(is(Pair!(int, "first", int, "second")));
+    static assert(is(Pair!(int, "first", int)));
+
+    static assert(is(Pair!(int, int, "second")));
+    static assert(!is(Pair!("first", int, "second", int)));
+    static assert(!is(Pair!(int, int, int)));
+
+    static assert(!is(Pair!(int, "first")));
+}