preprocess.c

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include "stack.h"

int num_cols = 100;
int num_rows = 100;

void free_bi_array(BracketInfo **bi) {
  for (int i = 0; i < num_rows; ++i) {
    free(bi[i]);
    bi[i] = NULL;
  }
  free(bi);
  bi = NULL;
}

void free_preprocess_info(PreprocessInfo *preprocess_info) {
  free_bi_array(preprocess_info->open_to_close);
  free_bi_array(preprocess_info->close_to_open);
  preprocess_info = NULL;
}

bool cmp_bracket_info(BracketInfo *me, BracketInfo *you) {
  return (me->linenum == you->linenum && me->pos == you->pos);
}

PreprocessInfo* preprocess_file(char* input_file) {
  FILE *fp;
  fp = fopen(input_file, "r");
  if (fp == NULL) {
    printf("Unable to open file. exiting\n");
    exit(1);
  }
  return preprocess(fp);
}

PreprocessInfo* preprocess(FILE *fp) {
  Stack brackets;
  init_stack(&brackets, 100);

  BracketInfo **open_to_close = (BracketInfo**)malloc(sizeof(BracketInfo*) * num_rows);
  for (int i = 0; i < num_rows; ++i) {
    open_to_close[i] = (BracketInfo*)malloc(sizeof(BracketInfo) * num_cols);
  }
  BracketInfo **close_to_open = (BracketInfo**)malloc(sizeof(BracketInfo*) * num_rows);
  for (int i = 0; i < num_rows; ++i) {
    close_to_open[i] = (BracketInfo*)malloc(sizeof(BracketInfo) * num_cols);
  }

  char *line = NULL;
  size_t linecap = 0;
  ssize_t linelen;
  char *tmp = NULL;

  int linenum = 0;
  int pos;
  BracketInfo open_bi;
  BracketInfo close_bi;
  BracketInfo null_bi = {-1, -1};
  while ((linelen = getline(&line, &linecap, fp)) > 0) {
    tmp = line;
    pos = 0;
    while (*tmp != '\0') {
      if (*tmp != '[' && *tmp != ']') {
        tmp++;
        pos++;
        continue;
      }
      if (*tmp == '[') {
        open_bi = (BracketInfo){linenum, pos};
        push(&brackets, &open_bi);
      } else {
        open_bi = pop(&brackets);
        if (cmp_bracket_info(&open_bi, &null_bi)) {
          fprintf(stderr, "[ERROR] compiler error - bracket mismatch.\n");
          return NULL;
        }
        close_bi = (BracketInfo){linenum, pos};
        open_to_close[open_bi.linenum][open_bi.pos] = close_bi;
        close_to_open[close_bi.linenum][close_bi.pos] = open_bi;
      }
      pos++;
      tmp++;
    }
    linenum++;
  }
  if (!is_empty(&brackets)) {
    fprintf(stderr, "[ERROR] compiler error - bracket mismatch.\n");
    return NULL;
  }
  PreprocessInfo *preprocess_info = (PreprocessInfo*)malloc(sizeof(PreprocessInfo));
  preprocess_info->open_to_close = open_to_close;
  preprocess_info->close_to_open = close_to_open;
  fclose(fp);
  return preprocess_info;
}