Exemple #1
0
/* parses(source) -> boolean */
int DuckParses(int argument_count, void* data)
{
    L_TOKEN*      lexing;
    char*         buffer;
    int           error = 0;

    VALUE argument = GetRecord("source", gCurrentContext);

    gLastExpression.type = VAL_PRIMITIVE;
    gLastExpression.data.primitive = 0;

    if (argument.type == VAL_STRING) 
    {
        lexing = LexSourceBuffer(argument.data.string, &buffer, CONTEXT_FREE_GRAMMAR);
        if (lexing == NULL) 
        {
            gLastExpression.data.primitive = -1;
            FreeLexing(lexing, buffer);
            //return 1;
            return 0;
        }
        gLastExpression.data.primitive = ParseSucceeds(lexing, PARSE_TABLE, CONTEXT_FREE_GRAMMAR);
        if (gLastExpression.data.primitive == 0) {
            FreeLexing(lexing, buffer);
            return 0;
        }

        /* free lexing */
        FreeLexing(lexing, buffer);
    }

    return error;
}
Exemple #2
0
/* lex a source file for a program */
L_TOKEN* LexSource(const char*    file,
                   char**         stripped,
                   GRAMMAR_TABLE  table)
{
    FILE* input;
    char* buffer;
    int   size;
    int   read;
	L_TOKEN* result;

    // read source file
    input = fopen(file, "rb");
    if (input == 0) {
        printf("Could not open source file.\n");
        return 0;
    }
    fseek(input, 0, SEEK_END);
    size = ftell(input);
    rewind(input);
    buffer = (char*)malloc(size+1);
    read = fread(buffer, 1, size, input);
    buffer[size] = 0;
    fclose(input);
    
    if (size == 0) {
        printf("Unable to read source file.\n");
        return 0;
    }

    // lex source file
    result = LexSourceBuffer(buffer, 
                             stripped, 
                             table);
    free(buffer);
    return result;
}
Exemple #3
0
/* eval(source) */
int DuckEval(int argument_count, void* data)
{
    L_TOKEN*      lexing;
    SYNTAX_TREE*  ast;
    char*         buffer;
    int           error = 0;

    VALUE argument = GetRecord("source", gCurrentContext);

    gLastExpression.type = VAL_NIL;
    gLastExpression.data.primitive = 0;

    CLOSURE* currentContext;
    currentContext = gCurrentContext;

    int prev_line_error = line_error;
    SYNTAX_TREE* prev_failed_production = failed_production;

//  if (gCurrentContext->parent) gCurrentContext = gCurrentContext->parent;
    gCurrentContext = gGlobalContext;

    if (argument.type == VAL_STRING) 
    {
        lexing = LexSourceBuffer(argument.data.string, &buffer, CONTEXT_FREE_GRAMMAR);
        if (lexing == NULL) {
            printf("Error lexing source or empty source string.\n");
            FreeLexing(lexing, buffer);
            return 1;
        }
        ast = ParseSource(lexing, PARSE_TABLE, CONTEXT_FREE_GRAMMAR);
        if (ast == NULL) {
            printf("Error parsing source.\n");
            FreeLexing(lexing, buffer);
            return 1;
        }

        /* ReduceProgramAST(&ast); */
        error = InterpretNode(ast);

        if (error)
        {
            printf("%s\n", ErrorMessage(error));
            PrintStackTrace();
            FreeLexing(lexing, buffer);
            FreeParseTree(ast);

            ClearCallStack(&gStackTrace);

            line_error = prev_line_error;
            failed_production = prev_failed_production;

            return 1;
        }

        /* sanitize last expression for use in program */
        //gLastExpression = ReallocStrings(gLastExpression);

        /* free lexing and parse tree */
        //FreeLexing(lexing, buffer);
        //FreeParseTree(ast);
        GCAddLexing(lexing, buffer);
        GCAddParseTree(ast);
    }

    gCurrentContext = currentContext;
    return error;
}