Function readChunk_tEXt

depends/lodepng/lodepng.cpp:4431–4468

text chunk (tEXt)*/

/*text chunk (tEXt)*/
static unsigned readChunk_tEXt(LodePNGInfo* info, const unsigned char* data, size_t chunkLength) {
  unsigned error = 0;
  char *key = 0, *str = 0;

  while(!error) /*not really a while loop, only used to break on error*/ {
    unsigned length, string2_begin;

    length = 0;
    while(length < chunkLength && data[length] != 0) ++length;
    /*even though it's not allowed by the standard, no error is thrown if
    there's no null termination char, if the text is empty*/
    if(length < 1 || length > 79) CERROR_BREAK(error, 89); /*keyword too short or long*/

    key = (char*)lodepng_malloc(length + 1);
    if(!key) CERROR_BREAK(error, 83); /*alloc fail*/

    lodepng_memcpy(key, data, length);
    key[length] = 0;

    string2_begin = length + 1; /*skip keyword null terminator*/

    length = (unsigned)(chunkLength < string2_begin ? 0 : chunkLength - string2_begin);
    str = (char*)lodepng_malloc(length + 1);
    if(!str) CERROR_BREAK(error, 83); /*alloc fail*/

    lodepng_memcpy(str, data + string2_begin, length);
    str[length] = 0;

    error = lodepng_add_text(info, key, str);

    break;
  }

  lodepng_free(key);
  lodepng_free(str);

  return error;
}

/*compressed text chunk (zTXt)*/
static unsigned readChunk_zTXt(LodePNGInfo* info, const LodePNGDecoderSettings* decoder,