Abstract the file reading
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@ -3,7 +3,333 @@
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*/
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module elna.extended;
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import core.stdc.errno;
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import core.stdc.stdio;
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import std.sumtype;
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import std.typecons;
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import tanya.os.error;
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import tanya.container.array;
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import tanya.container.string;
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/**
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* File handle abstraction.
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*/
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struct File
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{
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@disable this(this);
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/// Plattform dependent file type.
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alias Handle = FILE*;
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/// Uninitialized file handle value.
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enum Handle invalid = null;
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/**
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* Relative position.
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*/
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enum Whence
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{
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/// Relative to the start of the file.
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set = SEEK_SET,
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/// Relative to the current cursor position.
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currentt = SEEK_CUR,
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/// Relative from the end of the file.
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end = SEEK_END,
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}
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/**
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* File open modes.
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*/
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enum Mode
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{
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/// Open the file for reading.
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read = 1 << 0,
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/// Open the file for writing. The stream is positioned at the beginning
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/// of the file.
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write = 1 << 1,
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/// Open the file for writing and remove its contents.
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truncate = 1 << 2,
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/// Open the file for writing. The stream is positioned at the end of
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/// the file.
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append = 1 << 3,
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}
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private enum Status
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{
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invalid,
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owned,
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borrowed,
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}
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private union Storage
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{
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Handle handle;
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ErrorCode errorCode;
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}
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private Storage storage;
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private Status status = Status.invalid;
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@disable this(scope return ref File f);
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@disable this();
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/**
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* Closes the file.
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*/
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~this() @nogc nothrow
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{
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if (this.status == Status.owned)
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{
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fclose(this.storage.handle);
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}
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this.storage.handle = invalid;
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this.status = Status.invalid;
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}
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/**
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* Construct the object with the given system handle. The won't be claused
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* in the descructor if this constructor is used.
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*
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* Params:
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* handle = File handle to be wrapped by this structure.
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*/
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this(Handle handle) @nogc nothrow pure @safe
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{
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this.storage.handle = handle;
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this.status = Status.borrowed;
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}
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/**
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* Returns: Plattform dependent file handle.
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*/
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@property Handle handle() @nogc nothrow pure @trusted
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{
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return valid ? this.storage.handle : invalid;
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}
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/**
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* Returns: An error code if an error has occurred.
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*/
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@property ErrorCode errorCode() @nogc nothrow pure @safe
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{
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return valid ? ErrorCode() : this.storage.errorCode;
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}
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/**
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* Returns: Whether a valid, opened file is represented.
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*/
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@property bool valid() @nogc nothrow pure @safe
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{
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return this.status != Status.invalid;
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}
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/**
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* Transfers the file into invalid state.
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*
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* Returns: The old file handle.
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*/
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Handle reset() @nogc nothrow pure @safe
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{
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if (!valid)
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{
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return invalid;
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}
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auto oldHandle = handle;
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this.status = Status.invalid;
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this.storage.errorCode = ErrorCode();
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return oldHandle;
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}
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/**
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* Sets stream position in the file.
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*
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* Params:
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* offset = File offset.
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* whence = File position to add the offset to.
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*
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* Returns: Error code if any.
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*/
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ErrorCode seek(size_t offset, Whence whence) @nogc nothrow
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{
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if (!valid)
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{
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return ErrorCode(ErrorCode.ErrorNo.badDescriptor);
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}
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if (fseek(this.storage.handle, offset, whence))
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{
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return ErrorCode(cast(ErrorCode.ErrorNo) errno);
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}
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return ErrorCode();
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}
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/**
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* Returns: Current offset or an error.
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*/
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SumType!(ErrorCode, size_t) tell() @nogc nothrow
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{
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if (!valid)
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{
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return typeof(return)(ErrorCode(ErrorCode.ErrorNo.badDescriptor));
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}
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auto result = ftell(this.storage.handle);
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if (result < 0)
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{
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return typeof(return)(ErrorCode(cast(ErrorCode.ErrorNo) errno));
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}
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return typeof(return)(cast(size_t) result);
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}
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/**
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* Params:
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* buffer = Destination buffer.
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*
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* Returns: Bytes read. $(D_PSYMBOL ErrorCode.ErrorNo.success) means that
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* while reading the file an unknown error has occurred.
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*/
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SumType!(ErrorCode, size_t) read(ubyte[] buffer) @nogc nothrow
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{
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if (!valid)
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{
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return typeof(return)(ErrorCode(ErrorCode.ErrorNo.badDescriptor));
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}
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const bytesRead = fread(buffer.ptr, 1, buffer.length, this.storage.handle);
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if (bytesRead == buffer.length || eof())
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{
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return typeof(return)(bytesRead);
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}
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return typeof(return)(ErrorCode());
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}
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/**
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* Params:
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* buffer = Source buffer.
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*
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* Returns: Bytes written. $(D_PSYMBOL ErrorCode.ErrorNo.success) means that
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* while reading the file an unknown error has occurred.
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*/
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SumType!(ErrorCode, size_t) write(const(ubyte)[] buffer) @nogc nothrow
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{
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if (!valid)
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{
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return typeof(return)(ErrorCode(ErrorCode.ErrorNo.badDescriptor));
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}
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const bytesWritten = fwrite(buffer.ptr, 1, buffer.length, this.storage.handle);
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if (bytesWritten == buffer.length)
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{
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return typeof(return)(buffer.length);
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}
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return typeof(return)(ErrorCode());
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}
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/**
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* Returns: EOF status of the file.
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*/
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bool eof() @nogc nothrow
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{
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return valid && feof(this.storage.handle) != 0;
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}
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/**
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* Constructs a file object that will be closed in the destructor.
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*
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* Params:
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* filename = The file to open.
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*
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* Returns: Opened file or an error.
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*/
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static File open(const(char)* filename, BitFlags!Mode mode) @nogc nothrow
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{
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char[3] modeBuffer = "\0\0\0";
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if (mode.truncate)
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{
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modeBuffer[0] = 'w';
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if (mode.read)
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{
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modeBuffer[1] = '+';
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}
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}
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else if (mode.append)
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{
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modeBuffer[0] = 'a';
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if (mode.read)
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{
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modeBuffer[1] = '+';
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}
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}
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else if (mode.read)
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{
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modeBuffer[0] = 'r';
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if (mode.write)
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{
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modeBuffer[1] = '+';
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}
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}
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auto newHandle = fopen(filename, modeBuffer.ptr);
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auto newFile = File(newHandle);
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if (newHandle is null)
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{
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newFile.status = Status.invalid;
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newFile.storage.errorCode = ErrorCode(cast(ErrorCode.ErrorNo) errno);
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}
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else
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{
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if (mode == BitFlags!Mode(Mode.write))
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{
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rewind(newHandle);
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}
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newFile.status = Status.owned;
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}
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return newFile;
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}
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}
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/**
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* Reads the whole file and returns its contents.
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*
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* Params:
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* sourceFilename = Source filename.
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*
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* Returns: File contents or an error.
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*
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* See_Also: $(D_PSYMBOL File.read)
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*/
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SumType!(ErrorCode, Array!ubyte) readFile(String sourceFilename) @nogc
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{
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enum size_t bufferSize = 255;
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auto sourceFile = File.open(sourceFilename.toStringz, BitFlags!(File.Mode)(File.Mode.read));
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if (!sourceFile.valid)
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{
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return typeof(return)(sourceFile.errorCode);
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}
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Array!ubyte sourceText;
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size_t totalRead;
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size_t bytesRead;
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do
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{
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sourceText.length = sourceText.length + bufferSize;
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const readStatus = sourceFile
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.read(sourceText[totalRead .. $].get)
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.match!(
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(ErrorCode errorCode) => nullable(errorCode),
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(size_t bytesRead_) {
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bytesRead = bytesRead_;
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return Nullable!ErrorCode();
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}
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);
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if (!readStatus.isNull)
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{
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return typeof(return)(readStatus.get);
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}
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totalRead += bytesRead;
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}
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while (bytesRead == bufferSize);
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sourceText.length = totalRead;
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return typeof(return)(sourceText);
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}
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@ -5,47 +5,43 @@ import elna.lexer;
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import elna.parser;
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import elna.generator;
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import elna.ir;
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import elna.extended;
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import std.sumtype;
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import std.typecons;
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import tanya.container.array;
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import tanya.container.string;
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import tanya.memory.allocator;
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import tanya.memory.mmappool;
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import tanya.os.error;
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private char[] readSource(size_t N)(string source, out char[N] buffer) @nogc
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private Nullable!String readSource(string source) @nogc
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{
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memcpy(buffer.ptr, source.ptr, source.length + 1);
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buffer[source.length] = '\0';
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auto handle = fopen(buffer.ptr, "r");
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if (handle is null)
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{
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perror(buffer.ptr);
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return null;
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}
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fseek(handle, 0, SEEK_END);
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size_t fsize = ftell(handle);
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rewind(handle);
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enum size_t bufferSize = 255;
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auto sourceFilename = String(source);
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fread(buffer.ptr, fsize, 1, handle);
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fclose(handle);
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buffer[fsize] = '\0';
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return buffer[0 .. fsize];
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return readFile(sourceFilename).match!(
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(ErrorCode errorCode) {
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perror(sourceFilename.toStringz);
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return Nullable!String();
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},
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(Array!ubyte contents) => nullable(String(cast(char[]) contents.get))
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);
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}
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int main(string[] args)
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{
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char[255] buffer;
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defaultAllocator = MmapPool.instance;
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if (args.length < 2)
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{
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return 4;
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}
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auto sourceText = readSource(args[1], buffer);
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if (sourceText is null)
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auto sourceText = readSource(args[1]);
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if (sourceText.isNull)
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{
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return 3;
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}
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auto tokens = lex(sourceText);
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auto tokens = lex(sourceText.get.get);
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if (tokens.length == 0)
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{
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printf("Lexical analysis failed.\n");
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