experiments/flat/src/flat.c

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
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// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

#include "Common.h"
#include "Builtin.h"
#include "Parser.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define READ_SIZE 1024

static char *readStringFromFile(const char *filename)
{
    FILE *f = fopen(filename,"rb");
    if (f == NULL) {
        perror(filename);
        return NULL;
    }

    char *data = (char *)malloc(READ_SIZE);
    size_t len = 0;
    size_t r;
    while (0 < (r = fread(&data[len],1,READ_SIZE,f))) {
        len += r;
        data = (char*)realloc(data,len+READ_SIZE);
    }
    data = (char*)realloc(data,len+1);
    data[len] = '\0';
    fclose(f);
    return data;
}

int main(int argc, const char **argv)
{

    if ((argc == 2) && !strcmp(argv[1],"-g")) {
        // Build and print out the built-in PEG grammar
        Grammar *gram = GrammarNewBuiltin();
        GrammarPrint(gram);
        GrammarFree(gram);
    }
    else if ((argc == 3) && !strcmp(argv[1],"-p")) {
        const char *filename = argv[2];
        char *input = readStringFromFile(filename);
        if (input == NULL) {
            perror(filename);
            exit(1);
        }
        Grammar *gram = GrammarNewBuiltin();
        Term *term = parse(gram,"Grammar",input,0,strlen(input));
        TermPrint(term,input,"");
        free(input);
        GrammarFree(gram);
    }
    else {
        printf("Usage:\n"
               "\n"
               "flat -g            Print built-in PEG grammar\n"
               "\n"
               "flat -p FILENAME   Parse FILENAME using the built-in PEG grammar, and print\n"
               "                   the resulting parse tree\n");
        return 1;
    }
    return 0;
}