src/utils/str.c


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#include "str.h"
#include <stddef.h>

size_t strlen(const char *str) {
  size_t size = 0;
  for (; (str[size]) != '\0'; size++) {
  }
  return size;
}

char *str_reverse(char *str) {
  char *str_ptr = str;
  size_t size = strlen(str);
  char return_str[size];

  for (size_t i = 0; i < size; i++)
    return_str[size - i - 1] = str[i];

  for (size_t i = 0; i < size; i++)
    *str_ptr++ = return_str[i];

  return str;
}

char *itoa(int num, char *str) {
  char *str_ptr = str;
  for (; num;) {
    *str_ptr++ = num % 10 + 48;
    num /= 10;
  }
  str_reverse(str);
  return str;
}