/* What we do with the incoming data depends on what we were previously
* doing before we ran out of data...
*/
void /* PRIVATE */
png_process_some_data(png_structp png_ptr, png_infop info_ptr)
{
if(png_ptr == NULL) return;
png_ptr->process_mode = 1;
switch (png_ptr->process_mode)
{
case PNG_READ_SIG_MODE:
{
png_push_read_sig(png_ptr, info_ptr);
break;
}
case PNG_READ_CHUNK_MODE:
{
png_push_read_chunk(png_ptr, info_ptr);
break;
}
case PNG_READ_IDAT_MODE:
{
png_push_read_IDAT(png_ptr);
break;
}
#if defined(PNG_READ_tEXt_SUPPORTED)
case PNG_READ_tEXt_MODE:
{
png_push_read_tEXt(png_ptr, info_ptr);
break;
}
#endif
#if defined(PNG_READ_zTXt_SUPPORTED)
case PNG_READ_zTXt_MODE:
{
png_push_read_zTXt(png_ptr, info_ptr);
break;
}
#endif
#if defined(PNG_READ_iTXt_SUPPORTED)
case PNG_READ_iTXt_MODE:
{
png_push_read_iTXt(png_ptr, info_ptr);
break;
}
#endif
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
break;
}
default:
{
png_ptr->buffer_size = 0;
break;
}
}
}
/* What we do with the incoming data depends on what we were previously
* doing before we ran out of data...
*/
void /* PRIVATE */
png_process_some_data(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr == NULL)
return;
switch (png_ptr->process_mode)
{
case PNG_READ_SIG_MODE:
{
png_push_read_sig(png_ptr, info_ptr);
break;
}
case PNG_READ_CHUNK_MODE:
{
png_push_read_chunk(png_ptr, info_ptr);
break;
}
case PNG_READ_IDAT_MODE:
{
png_push_read_IDAT(png_ptr);
break;
}
case PNG_SKIP_MODE:
{
png_push_crc_finish(png_ptr);
break;
}
default:
{
png_ptr->buffer_size = 0;
break;
}
}
}
void /* PRIVATE */
png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->buffer_size && png_ptr->current_text_left)
{
png_size_t text_size;
if (png_ptr->buffer_size < png_ptr->current_text_left)
text_size = png_ptr->buffer_size;
else
text_size = png_ptr->current_text_left;
png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
png_ptr->current_text_left -= text_size;
png_ptr->current_text_ptr += text_size;
}
if (!(png_ptr->current_text_left))
{
png_textp text_ptr;
png_charp key;
int comp_flag;
png_charp lang;
png_charp lang_key;
png_charp text;
int ret;
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_crc_finish(png_ptr);
#if defined(PNG_MAX_MALLOC_64K)
if (png_ptr->skip_length)
return;
#endif
key = png_ptr->current_text;
for (lang = key; *lang; lang++)
/* empty loop */ ;
if (lang < key + png_ptr->current_text_size - 3)
lang++;
comp_flag = *lang++;
lang++; /* skip comp_type, always zero */
for (lang_key = lang; *lang_key; lang_key++)
/* empty loop */ ;
lang_key++; /* skip NUL separator */
text=lang_key;
if (lang_key < key + png_ptr->current_text_size - 1)
{
for (; *text; text++)
/* empty loop */ ;
}
if (text < key + png_ptr->current_text_size)
text++;
text_ptr = (png_textp)png_malloc(png_ptr,
(png_uint_32)png_sizeof(png_text));
text_ptr->compression = comp_flag + 2;
text_ptr->key = key;
text_ptr->lang = lang;
text_ptr->lang_key = lang_key;
text_ptr->text = text;
text_ptr->text_length = 0;
text_ptr->itxt_length = png_strlen(text);
ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
png_ptr->current_text = NULL;
png_free(png_ptr, text_ptr);
if (ret)
png_warning(png_ptr, "Insufficient memory to store iTXt chunk.");
}
}
void /* PRIVATE */
png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->buffer_size && png_ptr->current_text_left)
{
png_size_t text_size;
if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
text_size = png_ptr->buffer_size;
else
text_size = png_ptr->current_text_left;
png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
png_ptr->current_text_left -= text_size;
png_ptr->current_text_ptr += text_size;
}
if (!(png_ptr->current_text_left))
{
png_textp text_ptr;
png_charp text;
png_charp key;
int ret;
png_size_t text_size, key_size;
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_crc_finish(png_ptr);
key = png_ptr->current_text;
for (text = key; *text; text++)
/* empty loop */ ;
/* zTXt can't have zero text */
if (text >= key + png_ptr->current_text_size)
{
png_ptr->current_text = NULL;
png_free(png_ptr, key);
return;
}
text++;
if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
{
png_ptr->current_text = NULL;
png_free(png_ptr, key);
return;
}
text++;
png_ptr->zstream.next_in = (png_bytep )text;
png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
(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.");
}
}
void /* PRIVATE */
png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
{
if (png_ptr->buffer_size && png_ptr->current_text_left)
{
png_size_t text_size;
if (png_ptr->buffer_size < png_ptr->current_text_left)
text_size = png_ptr->buffer_size;
else
text_size = png_ptr->current_text_left;
png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
png_ptr->current_text_left -= text_size;
png_ptr->current_text_ptr += text_size;
}
if (!(png_ptr->current_text_left))
{
png_textp text_ptr;
png_charp text;
png_charp key;
int ret;
if (png_ptr->buffer_size < 4)
{
png_push_save_buffer(png_ptr);
return;
}
png_push_crc_finish(png_ptr);
#if defined(PNG_MAX_MALLOC_64K)
if (png_ptr->skip_length)
return;
#endif
key = png_ptr->current_text;
for (text = key; *text; text++)
/* empty loop */ ;
if (text < key + png_ptr->current_text_size)
text++;
text_ptr = (png_textp)png_malloc(png_ptr,
(png_uint_32)png_sizeof(png_text));
text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
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);
png_ptr->current_text = NULL;
if (ret)
png_warning(png_ptr, "Insufficient memory to store text chunk.");
}
}