C++ png_warning函数代码示例

//.........这里部分代码省略.........

    width  = (unsigned int)tiff_info.width;
    height = (unsigned int)tiff_info.height;
    pixel_size   = tiff_info.samples_per_pixel;
    sample_depth = tiff_info.bits_per_sample;
    switch (pixel_size)
    {
    case 1:
        color_type = PNG_COLOR_TYPE_GRAY;
        break;
    case 2:
        color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
        break;
    case 3:
        color_type = PNG_COLOR_TYPE_RGB;
        break;
    case 4:
        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
        break;
    default:
        png_error(png_ptr, "Unsupported TIFF color space");
        return 0;  /* avoid "uninitialized color_type" warning */
    }
    if (sample_depth > 16)
        png_error(png_ptr, "Unsupported TIFF sample depth");
    sample_max = (1 << sample_depth) - 1;
    sample_overflow = 0;

    png_set_IHDR(png_ptr, info_ptr, width, height,
                 (sample_depth <= 8) ? 8 : 16,
                 color_type,
                 PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
    row_pointers = pngx_malloc_rows(png_ptr, info_ptr, 0);

    if (sample_depth <= 8)
    {
        for (i = 0; i < height; ++i)
        {
            row = row_pointers[i];
            minitiff_read_row(&tiff_info, row, i, stream);
            if (sample_depth < 8)
            {
                for (j = 0; j < pixel_size * width; ++j)
                {
                    unsigned int b = row[j];
                    if (b > sample_max)
                    {
                        b = sample_max;
                        sample_overflow = 1;
                    }
                    row[j] = (png_byte)((b * 255 + sample_max / 2) / sample_max);
                }
            }
            if (tiff_info.photometric == 0)
            {
                for (j = 0; j < pixel_size * width; ++j)
                    row[j] = (png_byte)(255 - row[j]);
            }
        }
    }
    else
    {
        for (i = 0; i < height; ++i)
        {
            row = row_pointers[i];
            minitiff_read_row(&tiff_info, row, i, stream);
            if (tiff_info.byte_order == 'I')
            {
                /* "Intel" byte order => swap row bytes */
                for (j = k = 0; j < pixel_size * width; ++j, k+=2)
                {
                    png_byte b = row[k];
                    row[k] = row[k + 1];
                    row[k + 1] = b;
                }
            }
            if (sample_depth < 16)
            {
                for (j = k = 0; k < pixel_size * width; ++j, k+=2)
                {
                    unsigned int b = (row[k] << 8) + row[k + 1];
                    if (b > sample_max)
                    {
                        b = sample_max;
                        sample_overflow = 1;
                    }
                    b = (b * 65535U + sample_max / 2) / sample_max;
                    row[k] = (png_byte)(b >> 8);
                    row[k + 1] = (png_byte)(b & 255);
                }
            }
        }
    }

    if (sample_overflow)
        png_warning(png_ptr, "Overflow in TIFF samples");

    minitiff_destroy_info(&tiff_info);
    return 1 + num_extra_images;
}

//.........这里部分代码省略.........
         (text - key));
      png_ptr->zstream.next_out = png_ptr->zbuf;
      png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;

      key_size = text - key;
      text_size = 0;
      text = NULL;
      ret = Z_STREAM_END;

      while (png_ptr->zstream.avail_in)
      {
         ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
         if (ret != Z_OK && ret != Z_STREAM_END)
         {
            inflateReset(&png_ptr->zstream);
            png_ptr->zstream.avail_in = 0;
            png_ptr->current_text = NULL;
            png_free(png_ptr, key);
            png_free(png_ptr, text);
            return;
         }
         if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
         {
            if (text == NULL)
            {
               text = (png_charp)png_malloc(png_ptr,
                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
                     + key_size + 1));
               png_memcpy(text + key_size, png_ptr->zbuf,
                  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
               png_memcpy(text, key, key_size);
               text_size = key_size + png_ptr->zbuf_size -
                  png_ptr->zstream.avail_out;
               *(text + text_size) = '\0';
            }
            else
            {
               png_charp tmp;

               tmp = text;
               text = (png_charp)png_malloc(png_ptr, text_size +
                  (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
                   + 1));
               png_memcpy(text, tmp, text_size);
               png_free(png_ptr, tmp);
               png_memcpy(text + text_size, png_ptr->zbuf,
                  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
               text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
               *(text + text_size) = '\0';
            }
            if (ret != Z_STREAM_END)
            {
               png_ptr->zstream.next_out = png_ptr->zbuf;
               png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
            }
         }
         else
         {
            break;
         }

         if (ret == Z_STREAM_END)
            break;
      }

      inflateReset(&png_ptr->zstream);
      png_ptr->zstream.avail_in = 0;

      if (ret != Z_STREAM_END)
      {
         png_ptr->current_text = NULL;
         png_free(png_ptr, key);
         png_free(png_ptr, text);
         return;
      }

      png_ptr->current_text = NULL;
      png_free(png_ptr, key);
      key = text;
      text += key_size;

      text_ptr = (png_textp)png_malloc(png_ptr,
          (png_uint_32)png_sizeof(png_text));
      text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
      text_ptr->key = key;
#ifdef PNG_iTXt_SUPPORTED
      text_ptr->lang = NULL;
      text_ptr->lang_key = NULL;
#endif
      text_ptr->text = text;

      ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);

      png_free(png_ptr, key);
      png_free(png_ptr, text_ptr);

      if (ret)
        png_warning(png_ptr, "Insufficient memory to store text chunk.");
   }
}

/* This function is called when we haven't found a handler for this
 * chunk.  If there isn't a problem with the chunk itself (ie a bad chunk
 * name or a critical chunk), the chunk is (currently) silently ignored.
 */
void /* PRIVATE */
png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32
   length)
{
   png_uint_32 skip=0;
   png_check_chunk_name(png_ptr, png_ptr->chunk_name);

   if (!(png_ptr->chunk_name[0] & 0x20))
   {
#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
      if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
           PNG_HANDLE_CHUNK_ALWAYS
#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
           && png_ptr->read_user_chunk_fn == NULL
#endif
         )
#endif
         png_chunk_error(png_ptr, "unknown critical chunk");

      /* to quiet compiler warnings about unused info_ptr */
      if (info_ptr == NULL)
         return;
   }

#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
   if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
   {
#ifdef PNG_MAX_MALLOC_64K
       if (length > (png_uint_32)65535L)
       {
           png_warning(png_ptr, "unknown chunk too large to fit in memory");
           skip = length - (png_uint_32)65535L;
           length = (png_uint_32)65535L;
       }
#endif
       png_strcpy((png_charp)png_ptr->unknown_chunk.name,
         (png_charp)png_ptr->chunk_name);
       png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
       png_ptr->unknown_chunk.size = (png_size_t)length;
       png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
       if(png_ptr->read_user_chunk_fn != NULL)
       {
          /* callback to user unknown chunk handler */
          int ret;
          ret = (*(png_ptr->read_user_chunk_fn))
            (png_ptr, &png_ptr->unknown_chunk);
          if (ret < 0)
             png_chunk_error(png_ptr, "error in user chunk");
          if (ret == 0)
          {
             if (!(png_ptr->chunk_name[0] & 0x20))
                if(png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
                     PNG_HANDLE_CHUNK_ALWAYS)
                   png_chunk_error(png_ptr, "unknown critical chunk");
                png_set_unknown_chunks(png_ptr, info_ptr,
                   &png_ptr->unknown_chunk, 1);
          }
       }
#else
       png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
#endif
       png_free(png_ptr, png_ptr->unknown_chunk.data);
       png_ptr->unknown_chunk.data = NULL;
   }
   else
#endif
      skip=length;
   png_push_crc_skip(png_ptr, skip);
}

void PNGAPI
png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
                png_size_t png_struct_size)
{
#ifdef PNG_SETJMP_SUPPORTED
  jmp_buf tmp_jmp;  /* to save current jump buffer */
#endif

  int i = 0;

  png_structp png_ptr = *ptr_ptr;

  do {
    if (user_png_ver[i] != png_libpng_ver[i]) {
#ifdef PNG_LEGACY_SUPPORTED
      png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
#else
      png_ptr->warning_fn = NULL;
      png_warning(png_ptr,
                  "Application uses deprecated png_read_init() and should be recompiled.");
      break;
#endif
    }
  } while (png_libpng_ver[i++]);

  png_debug(1, "in png_read_init_3\n");

#ifdef PNG_SETJMP_SUPPORTED
  /* save jump buffer and error functions */
  png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
#endif

  if (png_sizeof(png_struct) > png_struct_size) {
    png_destroy_struct(png_ptr);
    *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
    png_ptr = *ptr_ptr;
  }

  /* reset all variables to 0 */
  png_memset(png_ptr, 0, png_sizeof(png_struct));

#ifdef PNG_SETJMP_SUPPORTED
  /* restore jump buffer */
  png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
#endif

  /* added at libpng-1.2.6 */
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
  png_ptr->user_width_max = PNG_USER_WIDTH_MAX;
  png_ptr->user_height_max = PNG_USER_HEIGHT_MAX;
#endif

  /* initialize zbuf - compression buffer */
  png_ptr->zbuf_size = PNG_ZBUF_SIZE;
  png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
                                        (png_uint_32)png_ptr->zbuf_size);
  png_ptr->zstream.zalloc = png_zalloc;
  png_ptr->zstream.zfree = png_zfree;
  png_ptr->zstream.opaque = (voidpf)png_ptr;

  switch (inflateInit(&png_ptr->zstream)) {
  case Z_OK: /* Do nothing */
    break;

  case Z_MEM_ERROR:
  case Z_STREAM_ERROR:
    png_error(png_ptr, "zlib memory");
    break;

  case Z_VERSION_ERROR:
    png_error(png_ptr, "zlib version");
    break;

  default:
    png_error(png_ptr, "Unknown zlib error");
  }

  png_ptr->zstream.next_out = png_ptr->zbuf;
  png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;

  png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
}

void PNGAPI
png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
{
#ifdef PNG_USE_LOCAL_ARRAYS
  PNG_IDAT;
  const int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
  const int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
#endif
  int ret;
  png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
             png_ptr->row_number, png_ptr->pass);

  if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) {
    png_read_start_row(png_ptr);
  }

  if (png_ptr->row_number == 0 && png_ptr->pass == 0) {
    /* check for transforms that have been set but were defined out */
#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
    if (png_ptr->transformations & PNG_INVERT_MONO) {
      png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)

    if (png_ptr->transformations & PNG_FILLER) {
      png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)

    if (png_ptr->transformations & PNG_PACKSWAP) {
      png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)

    if (png_ptr->transformations & PNG_PACK) {
      png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)

    if (png_ptr->transformations & PNG_SHIFT) {
      png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)

    if (png_ptr->transformations & PNG_BGR) {
      png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
    }

#endif
#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)

    if (png_ptr->transformations & PNG_SWAP_BYTES) {
      png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
    }

#endif
  }

#if defined(PNG_READ_INTERLACING_SUPPORTED)

  /* if interlaced and we do not need a new row, combine row and return */
  if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) {
    switch (png_ptr->pass) {
    case 0:
      if (png_ptr->row_number & 0x07) {
        if (dsp_row != NULL)
          png_combine_row(png_ptr, dsp_row,
                          png_pass_dsp_mask[png_ptr->pass]);

        png_read_finish_row(png_ptr);
        return;
      }

      break;

    case 1:
      if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) {
        if (dsp_row != NULL)
          png_combine_row(png_ptr, dsp_row,
                          png_pass_dsp_mask[png_ptr->pass]);

        png_read_finish_row(png_ptr);
        return;
      }

      break;

    case 2:
      if ((png_ptr->row_number & 0x07) != 4) {
        if (dsp_row != NULL && (png_ptr->row_number & 4))
//.........这里部分代码省略.........

/* This allows us to influence the way in which libpng chooses the "best"
 * filter for the current scanline.  While the "minimum-sum-of-absolute-
 * differences metric is relatively fast and effective, there is some
 * question as to whether it can be improved upon by trying to keep the
 * filtered data going to zlib more consistent, hopefully resulting in
 * better compression.
 */
#if defined(PNG_WRITE_WEIGHTED_FILTER_SUPPORTED)      /* GRR 970116 */
void
png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
   int num_weights, png_doublep filter_weights,
   png_doublep filter_costs)
{
   int i;

   png_debug(1, "in png_set_filter_heuristics\n");
   if (heuristic_method >= PNG_FILTER_HEURISTIC_LAST)
   {
      png_warning(png_ptr, "Unknown filter heuristic method");
      return;
   }

   if (heuristic_method == PNG_FILTER_HEURISTIC_DEFAULT)
   {
      heuristic_method = PNG_FILTER_HEURISTIC_UNWEIGHTED;
   }

   if (num_weights < 0 || filter_weights == NULL ||
      heuristic_method == PNG_FILTER_HEURISTIC_UNWEIGHTED)
   {
      num_weights = 0;
   }

   png_ptr->num_prev_filters = num_weights;
   png_ptr->heuristic_method = heuristic_method;

   if (num_weights > 0)
   {
      if (png_ptr->prev_filters == NULL)
      {
         png_ptr->prev_filters = (png_bytep)png_malloc(png_ptr,
            (png_uint_32)(sizeof(png_byte) * num_weights));

         /* To make sure that the weighting starts out fairly */
         for (i = 0; i < num_weights; i++)
         {
            png_ptr->prev_filters[i] = 255;
         }
      }

      if (png_ptr->filter_weights == NULL)
      {
         png_ptr->filter_weights = (png_uint_16p) png_malloc(png_ptr,
            (png_uint_32)(sizeof(png_uint_16) * num_weights));

         png_ptr->inv_filter_weights = (png_uint_16p) png_malloc(png_ptr,
            (png_uint_32)(sizeof(png_uint_16) * num_weights));

         for (i = 0; i < num_weights; i++)
         {
            png_ptr->inv_filter_weights[i] =
            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
         }
      }

      for (i = 0; i < num_weights; i++)
      {
         if (filter_weights[i] < 0.0)
         {
            png_ptr->inv_filter_weights[i] =
            png_ptr->filter_weights[i] = PNG_WEIGHT_FACTOR;
         }
         else
         {
            png_ptr->inv_filter_weights[i] =
               (png_uint_16)((double)PNG_WEIGHT_FACTOR*filter_weights[i]+0.5);
            png_ptr->filter_weights[i] =
               (png_uint_16)((double)PNG_WEIGHT_FACTOR/filter_weights[i]+0.5);
         }
      }
   }

   /* If, in the future, there are other filter methods, this would
    * need to be based on png_ptr->filter.
    */
   if (png_ptr->filter_costs == NULL)
   {
      png_ptr->filter_costs = (png_uint_16p) png_malloc(png_ptr,
         (png_uint_32)(sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));

      png_ptr->inv_filter_costs = (png_uint_16p) png_malloc(png_ptr,
         (png_uint_32)(sizeof(png_uint_16) * PNG_FILTER_VALUE_LAST));

      for (i = 0; i < PNG_FILTER_VALUE_LAST; i++)
      {
         png_ptr->inv_filter_costs[i] =
         png_ptr->filter_costs[i] = PNG_COST_FACTOR;
      }
   }

//.........这里部分代码省略.........

//.........这里部分代码省略.........

#ifdef PNG_WRITE_tIME_SUPPORTED
   if (info_ptr->valid & PNG_INFO_tIME)
   {
      png_write_tIME(png_ptr, &(info_ptr->mod_time));
      png_ptr->mode |= PNG_WROTE_tIME;
   }
#endif /* tIME */

#ifdef PNG_WRITE_sPLT_SUPPORTED
   if (info_ptr->valid & PNG_INFO_sPLT)
      for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
         png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
#endif /* sPLT */

#ifdef PNG_WRITE_TEXT_SUPPORTED
   /* Check to see if we need to write text chunks */
   for (i = 0; i < info_ptr->num_text; i++)
   {
      png_debug2(2, "Writing header text chunk %d, type %d", i,
          info_ptr->text[i].compression);
      /* An internationalized chunk? */
      if (info_ptr->text[i].compression > 0)
      {
#ifdef PNG_WRITE_iTXt_SUPPORTED
         /* Write international chunk */
         png_write_iTXt(png_ptr,
             info_ptr->text[i].compression,
             info_ptr->text[i].key,
             info_ptr->text[i].lang,
             info_ptr->text[i].lang_key,
             info_ptr->text[i].text);
         /* Mark this chunk as written */
         if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
         else
            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
#else
         png_warning(png_ptr, "Unable to write international text");
#endif
      }

      /* If we want a compressed text chunk */
      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_zTXt)
      {
#ifdef PNG_WRITE_zTXt_SUPPORTED
         /* Write compressed chunk */
         png_write_zTXt(png_ptr, info_ptr->text[i].key,
             info_ptr->text[i].text, 0,
             info_ptr->text[i].compression);
         /* Mark this chunk as written */
         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
#else
         png_warning(png_ptr, "Unable to write compressed text");
#endif
      }

      else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
      {
#ifdef PNG_WRITE_tEXt_SUPPORTED
         /* Write uncompressed chunk */
         png_write_tEXt(png_ptr, info_ptr->text[i].key,
             info_ptr->text[i].text,
             0);
         /* Mark this chunk as written */
         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
#else
         /* Can't get here */
         png_warning(png_ptr, "Unable to write uncompressed text");
#endif
      }
   }
#endif /* tEXt */

#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
   if (info_ptr->unknown_chunks_num)
   {
      png_unknown_chunk *up;

      png_debug(5, "writing extra chunks");

      for (up = info_ptr->unknown_chunks;
           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
           up++)
      {
         int keep = png_handle_as_unknown(png_ptr, up->name);
         if (keep != PNG_HANDLE_CHUNK_NEVER &&
             up->location &&
             (up->location & PNG_HAVE_PLTE) &&
             !(up->location & PNG_HAVE_IDAT) &&
             !(up->location & PNG_AFTER_IDAT) &&
             ((up->name[3] & 0x20) || keep == PNG_HANDLE_CHUNK_ALWAYS ||
             (png_ptr->flags & PNG_FLAG_KEEP_UNSAFE_CHUNKS)))
         {
            png_write_chunk(png_ptr, up->name, up->data, up->size);
         }
      }
   }
#endif
}

void PNGAPI
png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
    int nparams, png_const_charp units, png_charpp params)
{
   png_size_t length;
   int i;

   png_debug1(1, "in %s storage function", "pCAL");

   if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
       || (nparams > 0 && params == NULL))
      return;

   length = strlen(purpose) + 1;
   png_debug1(3, "allocating purpose for info (%lu bytes)",
       (unsigned long)length);

   /* TODO: validate format of calibration name and unit name */

   /* Check that the type matches the specification. */
   if (type < 0 || type > 3)
      png_error(png_ptr, "Invalid pCAL equation type");

   if (nparams < 0 || nparams > 255)
      png_error(png_ptr, "Invalid pCAL parameter count");

   /* Validate params[nparams] */
   for (i=0; i<nparams; ++i)
   {
      if (params[i] == NULL ||
          !png_check_fp_string(params[i], strlen(params[i])))
         png_error(png_ptr, "Invalid format for pCAL parameter");
   }

   info_ptr->pcal_purpose = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, length));

   if (info_ptr->pcal_purpose == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL purpose");

      return;
   }

   memcpy(info_ptr->pcal_purpose, purpose, length);

   png_debug(3, "storing X0, X1, type, and nparams in info");
   info_ptr->pcal_X0 = X0;
   info_ptr->pcal_X1 = X1;
   info_ptr->pcal_type = (png_byte)type;
   info_ptr->pcal_nparams = (png_byte)nparams;

   length = strlen(units) + 1;
   png_debug1(3, "allocating units for info (%lu bytes)",
     (unsigned long)length);

   info_ptr->pcal_units = png_voidcast(png_charp,
      png_malloc_warn(png_ptr, length));

   if (info_ptr->pcal_units == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL units");

      return;
   }

   memcpy(info_ptr->pcal_units, units, length);

   info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
       (png_size_t)((nparams + 1) * (sizeof (png_charp)))));

   if (info_ptr->pcal_params == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL params");

      return;
   }

   memset(info_ptr->pcal_params, 0, (nparams + 1) * (sizeof (png_charp)));

   for (i = 0; i < nparams; i++)
   {
      length = strlen(params[i]) + 1;
      png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
          (unsigned long)length);

      info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);

      if (info_ptr->pcal_params[i] == NULL)
      {
         png_warning(png_ptr, "Insufficient memory for pCAL parameter");

         return;
      }

      memcpy(info_ptr->pcal_params[i], params[i], length);
   }

   info_ptr->valid |= PNG_INFO_pCAL;
//.........这里部分代码省略.........

void PNGAPI
png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
    int unit, png_const_charp swidth, png_const_charp sheight)
{
   png_size_t lengthw = 0, lengthh = 0;

   png_debug1(1, "in %s storage function", "sCAL");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   /* Double check the unit (should never get here with an invalid
    * unit unless this is an API call.)
    */
   if (unit != 1 && unit != 2)
      png_error(png_ptr, "Invalid sCAL unit");

   if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
       swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
      png_error(png_ptr, "Invalid sCAL width");

   if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
       sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
      png_error(png_ptr, "Invalid sCAL height");

   info_ptr->scal_unit = (png_byte)unit;

   ++lengthw;

   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);

   info_ptr->scal_s_width = png_voidcast(png_charp,
      png_malloc_warn(png_ptr, lengthw));

   if (info_ptr->scal_s_width == NULL)
   {
      png_warning(png_ptr, "Memory allocation failed while processing sCAL");

      return;
   }

   memcpy(info_ptr->scal_s_width, swidth, lengthw);

   ++lengthh;

   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);

   info_ptr->scal_s_height = png_voidcast(png_charp,
      png_malloc_warn(png_ptr, lengthh));

   if (info_ptr->scal_s_height == NULL)
   {
      png_free (png_ptr, info_ptr->scal_s_width);
      info_ptr->scal_s_width = NULL;

      png_warning(png_ptr, "Memory allocation failed while processing sCAL");

      return;
   }

   memcpy(info_ptr->scal_s_height, sheight, lengthh);

   info_ptr->valid |= PNG_INFO_sCAL;
   info_ptr->free_me |= PNG_FREE_SCAL;
}

void PNGAPI
png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
   int num_text)
{
   int i;

   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
      "text" : (png_const_charp)png_ptr->chunk_name));

   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
      return;

   /* Make sure we have enough space in the "text" array in info_struct
    * to hold all of the incoming text_ptr objects.
    */
   if (info_ptr->num_text + num_text > info_ptr->max_text)
   {
      if (info_ptr->text != NULL)
      {
         png_textp old_text;
         int old_max;

         old_max = info_ptr->max_text;
         info_ptr->max_text = info_ptr->num_text + num_text + 8;
         old_text = info_ptr->text;
         info_ptr->text = (png_textp)png_malloc(png_ptr,
            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
            sizeof(png_text)));
         png_free(png_ptr, old_text);
      }
      else
      {
         info_ptr->max_text = num_text + 8;
         info_ptr->num_text = 0;
         info_ptr->text = (png_textp)png_malloc(png_ptr,
            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
#ifdef PNG_FREE_ME_SUPPORTED
         info_ptr->free_me |= PNG_FREE_TEXT;
#endif
      }
      png_debug1(3, "allocated %d entries for info_ptr->text\n",
         info_ptr->max_text);
   }
   for (i = 0; i < num_text; i++)
   {
      png_size_t text_length,key_len;
      png_size_t lang_len,lang_key_len;
      png_textp textp = &(info_ptr->text[info_ptr->num_text]);

      if (text_ptr[i].key == (png_charp)NULL)
          continue;

      key_len = png_strlen(text_ptr[i].key);

      if(text_ptr[i].compression <= 0)
      {
        lang_len = 0;
        lang_key_len = 0;
      }
      else
#ifdef PNG_iTXt_SUPPORTED
      {
        /* set iTXt data */
        if (text_ptr[i].key != (png_charp)NULL)
          lang_len = png_strlen(text_ptr[i].lang);
        else
          lang_len = 0;
        if (text_ptr[i].lang_key != (png_charp)NULL)
          lang_key_len = png_strlen(text_ptr[i].lang_key);
        else
          lang_key_len = 0;
      }
#else
      {
        png_warning(png_ptr, "iTXt chunk not supported.");
        continue;
      }
#endif

      if (text_ptr[i].text == (png_charp)NULL || text_ptr[i].text[0] == '\0')
      {
         text_length = 0;
#ifdef PNG_iTXt_SUPPORTED
         if(text_ptr[i].compression > 0)
            textp->compression = PNG_ITXT_COMPRESSION_NONE;
         else
#endif
            textp->compression = PNG_TEXT_COMPRESSION_NONE;
      }
      else
      {
         text_length = png_strlen(text_ptr[i].text);
         textp->compression = text_ptr[i].compression;
      }

      textp->key = (png_charp)png_malloc(png_ptr,
         (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
      png_debug2(2, "Allocated %d bytes at %x in png_set_text\n",
         key_len + lang_len + lang_key_len + text_length + 4, (int)textp->key);
//.........这里部分代码省略.........

static void
pngx_gif_warning(const char *msg)
{
   png_warning(pngx_err_ptr, msg);
}

void
png_formatted_warning(png_structp png_ptr, png_warning_parameters p,
   png_const_charp message)
{
   /* The internal buffer is just 128 bytes - enough for all our messages,
    * overflow doesn't happen because this code checks!
    */
   size_t i;
   char msg[128];

   for (i=0; i<(sizeof msg)-1 && *message != '\0'; ++i)
   {
      if (*message == '@')
      {
         int parameter = -1;
         switch (*++message)
         {
            case '1':
               parameter = 0;
               break;

            case '2':
               parameter = 1;
               break;

            case '\0':
               continue; /* To break out of the for loop above. */

            default:
               break;
         }

         if (parameter >= 0 && parameter < PNG_WARNING_PARAMETER_COUNT)
         {
            /* Append this parameter */
            png_const_charp parm = p[parameter];
            png_const_charp pend = p[parameter] + (sizeof p[parameter]);

            /* No need to copy the trailing '\0' here, but there is no guarantee
             * that parm[] has been initialized, so there is no guarantee of a
             * trailing '\0':
             */
            for (; i<(sizeof msg)-1 && parm != '\0' && parm < pend; ++i)
               msg[i] = *parm++;

            ++message;
            continue;
         }

         /* else not a parameter and there is a character after the @ sign; just
          * copy that.
          */
      }

      /* At this point *message can't be '\0', even in the bad parameter case
       * above where there is a lone '@' at the end of the message string.
       */
      msg[i] = *message++;
   }

   /* i is always less than (sizeof msg), so: */
   msg[i] = '\0';

   /* And this is the formatted message: */
   png_warning(png_ptr, msg);
}

void PNGAPI
png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
    png_const_colorp palette, int num_palette)
{

   png_uint_32 max_palette_length;

   png_debug1(1, "in %s storage function", "PLTE");

   if (png_ptr == NULL || info_ptr == NULL)
      return;

   max_palette_length = (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
      (1 << info_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;

   if (num_palette < 0 || num_palette > (int) max_palette_length)
   {
      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
         png_error(png_ptr, "Invalid palette length");

      else
      {
         png_warning(png_ptr, "Invalid palette length");

         return;
      }
   }

   if ((num_palette > 0 && palette == NULL) ||
      (num_palette == 0
#        ifdef PNG_MNG_FEATURES_SUPPORTED
            && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
#        endif
      ))
   {
      png_error(png_ptr, "Invalid palette");
   }

   /* It may not actually be necessary to set png_ptr->palette here;
    * we do it for backward compatibility with the way the png_handle_tRNS
    * function used to do the allocation.
    *
    * 1.6.0: the above statement appears to be incorrect; something has to set
    * the palette inside png_struct on read.
    */
   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);

   /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
    * of num_palette entries, in case of an invalid PNG file or incorrect
    * call to png_set_PLTE() with too-large sample values.
    */
   png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
       PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));

   if (num_palette > 0)
      memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
   info_ptr->palette = png_ptr->palette;
   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;

   info_ptr->free_me |= PNG_FREE_PLTE;

   info_ptr->valid |= PNG_INFO_PLTE;
}

/* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
 * and if invalid, correct the keyword rather than discarding the entire
 * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
 * length, forbids leading or trailing whitespace, multiple internal spaces,
 * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
 *
 * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
 * trailing '\0').  If this routine returns 0 then there was no keyword, or a
 * valid one could not be generated, and the caller must png_error.
 */
png_uint_32 /* PRIVATE */
png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
{
   png_const_charp orig_key = key;
   png_uint_32 key_len = 0;
   int bad_character = 0;
   int space = 1;

   png_debug(1, "in png_check_keyword");

   if (key == NULL)
   {
      *new_key = 0;
      return 0;
   }

   while (*key && key_len < 79)
   {
      png_byte ch = (png_byte)*key++;

      if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
         *new_key++ = ch, ++key_len, space = 0;

      else if (space == 0)
      {
         /* A space or an invalid character when one wasn't seen immediately
          * before; output just a space.
          */
         *new_key++ = 32, ++key_len, space = 1;

         /* If the character was not a space then it is invalid. */
         if (ch != 32)
            bad_character = ch;
      }

      else if (bad_character == 0)
         bad_character = ch; /* just skip it, record the first error */
   }

   if (key_len > 0 && space != 0) /* trailing space */
   {
      --key_len, --new_key;
      if (bad_character == 0)
         bad_character = 32;
   }

   /* Terminate the keyword */
   *new_key = 0;

   if (key_len == 0)
      return 0;

#ifdef PNG_WARNINGS_SUPPORTED
   /* Try to only output one warning per keyword: */
   if (*key != 0) /* keyword too long */
      png_warning(png_ptr, "keyword truncated");

   else if (bad_character != 0)
   {
      PNG_WARNING_PARAMETERS(p)

      png_warning_parameter(p, 1, orig_key);
      png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);

      png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '[email protected]'");
   }
#endif /* WARNINGS */

   return key_len;
}

/* called by user to write a row of image data */
void
png_write_row(png_structp png_ptr, png_bytep row)
{
   png_debug2(1, "in png_write_row (row %ld, pass %d)\n",
      png_ptr->row_number, png_ptr->pass);
   /* initialize transformations and other stuff if first time */
   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
   {
   /* check for transforms that have been set but were defined out */
#if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
   if (png_ptr->transformations & PNG_INVERT_MONO)
      png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
   if (png_ptr->transformations & PNG_FILLER)
      png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && defined(PNG_READ_PACKSWAP_SUPPORTED)
   if (png_ptr->transformations & PNG_PACKSWAP)
      png_warning(png_ptr, "PNG_WRITE_PACKSWAP_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
   if (png_ptr->transformations & PNG_PACK)
      png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
   if (png_ptr->transformations & PNG_SHIFT)
      png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
   if (png_ptr->transformations & PNG_BGR)
      png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined.");
#endif
#if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
   if (png_ptr->transformations & PNG_SWAP_BYTES)
      png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined.");
#endif

      png_write_start_row(png_ptr);
   }

#if defined(PNG_WRITE_INTERLACING_SUPPORTED)
   /* if interlaced and not interested in row, return */
   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
   {
      switch (png_ptr->pass)
      {
         case 0:
            if (png_ptr->row_number & 7)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 1:
            if ((png_ptr->row_number & 7) || png_ptr->width < 5)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 2:
            if ((png_ptr->row_number & 7) != 4)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 3:
            if ((png_ptr->row_number & 3) || png_ptr->width < 3)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 4:
            if ((png_ptr->row_number & 3) != 2)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 5:
            if ((png_ptr->row_number & 1) || png_ptr->width < 2)
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
         case 6:
            if (!(png_ptr->row_number & 1))
            {
               png_write_finish_row(png_ptr);
               return;
            }
            break;
      }
   }
#endif
//.........这里部分代码省略.........