An Efficient Platform for the Automatic Extraction of Patterns in Native Code

Algorithm 1

Example high-level C program.

char * str_slice(const char * str, int begin, int end)

  /* Check str */

  if (str == NULL)

    return NULL;

  /* Check ranges */

  int s = strlen(str);

  if ((!s) || (begin >= s) || (begin < s * −1) || (end >= s + 1)

      || (end < s * −1))

    return NULL;

  /* Normalice values */

  size_t n_begin = begin >= 0 ? begin: s + begin;

  size_t n_end = end >= 0 ? end: s + end;

  /* Check begin >= end */

  if (n_end <= n_begin)

    return NULL;

  /* Alloc mem */

  size_t amount = n_end − n_begin;

  char * new_str = malloc((amount + 1) * sizeof(char));

  if (new_str == NULL)

    return NULL;

  /* Copy */

  memcpy(new_str, str + n_begin, amount);

  new_str[amount] = 0;

  return new_str;