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kazinator on June 6, 2018 | parent | context | favorite | on: Beware of strncpy and strncat

Too many evaluations of a. If you have snprintf, you probably have inline functions.

One day someone will do something like strncat(a += previous_delta, ...).

dmitrygr on June 6, 2018 [–]

OPTION 1 (c):

  char* mystrncat(char *a, const char *b, size_t maxlen){
    snprintf(a + strlen(a), maxlen - strlen(a), "%s", b);
    return a;
  }

OPTION 2 (gccism):

   #define strncat(_a, b, maxlen) ({char* a = _a; snprintf(a + strlen(a), maxlen - strlen(a), "%s", b); _a;})

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