Allow comparing all pointer types to nil

This commit is contained in:
2025-02-03 23:04:00 +01:00
parent 607bf09434
commit aab16e4941
7 changed files with 187 additions and 98 deletions

View File

@ -1,3 +1,21 @@
const
SEEK_SET = 0, SEEK_CUR = 1, SEEK_END = 2,
TOKEN_IDENTIFIER = 1, TOKEN_IF = 2, TOKEN_THEN = 3, TOKEN_ELSE = 4, TOKEN_ELSIF = 5,
TOKEN_WHILE = 6, TOKEN_DO = 7, TOKEN_PROC = 8, TOKEN_BEGIN = 9, TOKEN_END = 10,
TOKEN_EXTERN = 11, TOKEN_CONST = 12, TOKEN_VAR = 13, TOKEN_ARRAY = 14, TOKEN_OF = 15,
TOKEN_TYPE = 16, TOKEN_RECORD = 17, TOKEN_UNION = 18, TOKEN_POINTER = 19, TOKEN_TO = 20,
TOKEN_BOOLEAN = 21, TOKEN_NIL = 22, TOKEN_AND = 23, TOKEN_OR = 24, TOKEN_NOT = 25,
TOKEN_RETURN = 26, TOKEN_CAST = 27, TOKEN_AS = 28, TOKEN_SIZEOF = 29,
TOKEN_LEFT_PAREN = 30, TOKEN_RIGHT_PAREN = 31, TOKEN_LEFT_SQUARE = 32,
TOKEN_RIGHT_SQUARE = 33, TOKEN_GREATER_EQUAL = 34, TOKEN_LESS_EQUAL = 35,
TOKEN_GREATER_THAN = 36, TOKEN_LESS_THAN = 37, TOKEN_NOT_EQUAL = 38, TOKEN_EQUAL = 39,
TOKEN_SEMICOLON = 40, TOKEN_DOT = 41, TOKEN_COMMA = 42,
TOKEN_PLUS = 43, TOKEN_MINUS = 44, TOKEN_MULTIPLICATION = 45, TOKEN_DIVISION = 46,
TOKEN_REMAINDER = 47, TOKEN_ASSIGNMENT = 48, TOKEN_COLON = 49, TOKEN_HAT = 50,
TOKEN_AT = 51, TOKEN_COMMENT = 52, TOKEN_INTEGER = 53, TOKEN_WORD = 54,
TOKEN_CHARACTER = 55, TOKEN_STRING = 56;
type
Position = record
line: Word;
@ -23,32 +41,29 @@ type
end,
CommandLine = record
input: pointer to Char
end,
Literal = record
value: Int
end,
ConstantDefinition = record
name: pointer to Char;
body: pointer to Literal
end,
ConstantPart = record
elements: pointer to pointer to ConstantDefinition;
count: Word
end,
Program = record
constants: ConstantPart
end;
const
SEEK_SET = 0, SEEK_CUR = 1, SEEK_END = 2,
TOKEN_IDENTIFIER = 1, TOKEN_IF = 2, TOKEN_THEN = 3, TOKEN_ELSE = 4, TOKEN_ELSIF = 5,
TOKEN_WHILE = 6, TOKEN_DO = 7, TOKEN_PROC = 8, TOKEN_BEGIN = 9, TOKEN_END = 10,
TOKEN_EXTERN = 11, TOKEN_CONST = 12, TOKEN_VAR = 13, TOKEN_ARRAY = 14, TOKEN_OF = 15,
TOKEN_TYPE = 16, TOKEN_RECORD = 17, TOKEN_UNION = 18, TOKEN_POINTER = 19, TOKEN_TO = 20,
TOKEN_BOOLEAN = 21, TOKEN_NIL = 22, TOKEN_AND = 23, TOKEN_OR = 24, TOKEN_NOT = 25,
TOKEN_RETURN = 26, TOKEN_CAST = 27, TOKEN_AS = 28, TOKEN_SIZEOF = 29,
TOKEN_LEFT_PAREN = 30, TOKEN_RIGHT_PAREN = 31, TOKEN_LEFT_SQUARE = 32,
TOKEN_RIGHT_SQUARE = 33, TOKEN_GREATER_EQUAL = 34, TOKEN_LESS_EQUAL = 35,
TOKEN_GREATER_THAN = 36, TOKEN_LESS_THAN = 37, TOKEN_NOT_EQUAL = 38, TOKEN_EQUAL = 39,
TOKEN_SEMICOLON = 40, TOKEN_DOT = 41, TOKEN_COMMA = 42,
TOKEN_PLUS = 43, TOKEN_MINUS = 44, TOKEN_MULTIPLICATION = 45, TOKEN_DIVISION = 46,
TOKEN_REMAINDER = 47, TOKEN_ASSIGNMENT = 48, TOKEN_COLON = 49, TOKEN_HAT = 50,
TOKEN_AT = 51, TOKEN_COMMENT = 52, TOKEN_INTEGER = 53, TOKEN_WORD = 54,
TOKEN_CHARACTER = 55, TOKEN_STRING = 56;
(*
External procedures.
*)
proc fopen(pathname: String, mode: String): pointer to FILE; extern;
proc fclose(stream: pointer to FILE): Int; extern;
proc fseek(stream: pointer to FILE, off: Int, whence: Int): Int; extern;
proc rewind(stream: pointer to FILE); extern;
proc ftell(stream: pointer to FILE): Int; extern;
proc fread(ptr: pointer to Byte, size: Word, nmemb: Word, stream: pointer to FILE): Word; extern;
proc write(fd: Int, buf: pointer to Byte, Word: Int): Int; extern;
@ -63,10 +78,12 @@ proc memset(ptr: pointer to Char, c: Int, n: Int): pointer to Char; extern;
proc strncmp(s1: pointer to Char, s2: pointer to Char, n: Word): Int; extern;
proc strncpy(dst: pointer to Char, src: pointer to Char, dsize: Word): pointer to Char; extern;
proc strcpy(dst: pointer to Char, src: pointer to Char): pointer to Char; extern;
proc strlen(ptr: pointer to Char): Word; extern;
proc strtol(nptr: pointer to Char, endptr: pointer to pointer to Char, base: Int): Int; extern;
proc perror(s: pointer to Char); extern;
proc exit(code: Int); extern;
(*
@ -152,13 +169,24 @@ var
begin
input_file := fopen(filename, "rb");
fseek(input_file, 0, SEEK_END);
if input_file = nil then
return nil
end;
if fseek(input_file, 0, SEEK_END) <> 0 then
fclose(input_file);
return nil
end;
source_size := ftell(input_file);
fseek(input_file, 0, SEEK_SET);
if source_size < 0 then
fclose(input_file);
return nil
end;
rewind(input_file);
input := calloc(source_size + 1, 1);
fread(input, source_size, 1, input_file);
if fread(input, source_size, 1, input_file) <> 1u then
input := cast(nil as pointer to Byte)
end;
fclose(input_file);
return input
@ -551,7 +579,7 @@ begin
if input_pointer^ = '*' then
token_end := lex_comment(input_pointer + 1);
if token_end <> cast(nil as pointer to Char) then
if token_end <> nil then
token_length := cast(token_end as Word) - cast(input_pointer as Word);
current_token^.value.string_value := cast(calloc(token_length + 1u, 1) as pointer to Char);
strncpy(current_token^.value.string_value, input_pointer, token_length);
@ -667,6 +695,65 @@ begin
return tokens
end;
proc parse_literal(tokens: pointer to pointer to Token, tokens_size: pointer to Word): pointer to Literal;
begin
return cast(calloc(1, sizeof(Literal)) as pointer to Literal)
end;
proc parse_constant_definition(tokens: pointer to pointer to Token,
tokens_size: pointer to Word): pointer to ConstantDefinition;
var
result: pointer to ConstantDefinition;
begin
result := cast(calloc(1, sizeof(ConstantDefinition)) as pointer to ConstantDefinition);
result^.name := cast(malloc(strlen(tokens^^.value.string_value)) as pointer to Char);
strcpy(result^.name, tokens^^.value.string_value);
tokens^ := tokens^ + sizeof(Token) * 2u;
tokens_size := tokens_size - sizeof(Token) * 2u;
write_s(result^.name);
write_c('\n');
result^.body := parse_literal(tokens, tokens_size);
tokens^ := tokens^ + sizeof(Token) * 2u;
tokens_size := tokens_size - sizeof(Token) * 2u;
return result
end;
proc parse_program(tokens: pointer to pointer to Token, tokens_size: pointer to Word): pointer to Program;
var
result: pointer to Program,
current_constant: pointer to pointer to ConstantDefinition;
begin
result := cast(calloc(1, sizeof(Program)) as pointer to Program);
result^.constants.elements := cast(nil as pointer to pointer to ConstantDefinition);
result^.constants.count := 0u;
if tokens^^.kind = TOKEN_CONST then
tokens^ := tokens^ + sizeof(Token);
tokens_size^ := tokens_size^ - sizeof(Token);
while tokens_size^ > 0u and tokens^^.kind = TOKEN_IDENTIFIER do
result^.constants.elements := cast(
reallocarray(result^.constants.elements, result^.constants.count + 1u, sizeof(pointer to ConstantDefinition))
as pointer to pointer to ConstantDefinition);
current_constant := result^.constants.elements + result^.constants.count * sizeof(pointer to ConstantDefinition);
result^.constants.count := result^.constants.count + 1u;
current_constant^ := parse_constant_definition(tokens, tokens_size);
if current_constant^ = nil then
return nil
end
end
end
end;
proc parse_command_line(argc: Int, argv: pointer to pointer to Char): pointer to CommandLine;
var
parameter: pointer to pointer to Char,
@ -712,11 +799,16 @@ begin
return 2
end;
input := read_source(command_line^.input);
if input = nil then
perror(command_line^.input);
return 3
end;
tokens := tokenize(input, @tokens_size);
free(input);
print_tokens(tokens, tokens_size);
print_tokens(tokens, tokens_size)
parse_program(@tokens, @tokens_size);
return 0
end;
begin