Tag: Review

I have written a program to parse a string depending on the string the user provides.
Any advise/criticism is appreciated.

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>

#define DEFAULT_SIZE 10
#define RESIZE_MULTI 2

/*compares value to see if it exists in parse. return 0 if exists*/
static uint8_t compare(const char value, const char *parse)
{
   size_t i;

   i = 0;
   while(*(parse + i) != '')
   {
      if(*(parse + i) == value)
         return 0;
      i++;
   }
   return 1;
}

/*string must be null terminated. the string that needs to be split*/
/*parse must be null terminated. contains value that the string will be split at*/
/*matrix contains all the string that was split based on parse. the function return how how many string there are*/
size_t parse_string(const char *string, const char *parse, char *** const user_matrix)
{
   /*how many spots there are*/
   size_t temp_matrix_size;
   /*how many acctually string there are*/
   size_t temp_matrix_length;
   char **temp_matrix;
   size_t i;
   size_t counter;

   /*allocate initial memory. array of pointers*/
   temp_matrix = malloc(sizeof(*temp_matrix) * DEFAULT_SIZE);
   if(temp_matrix == NULL)
      goto FAIL0;
   temp_matrix_size = DEFAULT_SIZE;
   /*since right now there 0 string aka pointers to strings*/
   temp_matrix_length = 0;


   i = counter = 0;
   while(*(string + i) != '')
   {
      /*resize array of pointers*/
      if(temp_matrix_length >= temp_matrix_size)
      {
         char **temp = realloc(temp_matrix, sizeof(*temp_matrix) * temp_matrix_size * RESIZE_MULTI);
         if(temp == NULL)
            goto FAIL0;
         temp_matrix = temp;
         temp_matrix_size = temp_matrix_size * RESIZE_MULTI;
      }

      if(compare(*(string + i), parse) == 0)
      {
         char *temp;
         if(counter > 0)
         {
            /*need the plus 1 for terminating char*/
            temp = malloc(sizeof(*temp) * (counter + 1));
            if(temp == NULL)
               goto FAIL0;

            /*setting terminating char*/
            *(temp + counter) = '';
            /*copy over the string before the parsing char*/
            memcpy(temp, string + (i - counter), counter);

            /*store the string*/
            *(temp_matrix + temp_matrix_length) = temp;
            temp_matrix_length++;
         }

         /*store only the parsing char with null terminated char*/
         temp = malloc(sizeof(*temp) * 2);
         if(temp == NULL)
            goto FAIL0;
         *(temp + 0) = *(string + i);
         *(temp + 1) = '';

         *(temp_matrix + temp_matrix_length) = temp;
         temp_matrix_length++;

         i++;
         counter = 0;
      }
      else
      {
         i++;
         counter++;
      }
   }

   /*special case*/
   if(counter != 0)
   {
      char *temp = malloc(sizeof(*temp) * (counter + 1));
      if(temp == NULL)
         goto FAIL0;

      /*setting terminating char*/
      *(temp + counter) = '';
      /*copy over the string before the parsing char*/
      memcpy(temp, string + (i - counter), counter);

      /*store the string*/
      *(temp_matrix + temp_matrix_length) = temp;
      temp_matrix_length++;
   }

   *user_matrix = temp_matrix;

   return temp_matrix_length;

   FAIL0:
   if(temp_matrix != NULL)
   {
      /*free all the strings*/
      for(i = 0; i < temp_matrix_length; i++)
      {
         free(*(temp_matrix + i));
      }
      /*free the array of pointers*/
      free(temp_matrix);
   }
   *user_matrix = NULL;
   return 0;
}

int main(void)
{
   char **matrix;
   size_t size;

   /*can have anything you want*/
   char *str = "Hello Word!!!";
   /*can have any char you want*/
   char *parse = "! ";

   size = parse_string(str, parse, &matrix);

   for(size_t i = 0; i < size; i++)
   {
      printf("%sn", *(matrix + i));
   }

   for(size_t i = 0; i < size; i++)
   {
      free(*(matrix + i));
   }
   free(matrix);

   return 0;
}