From d57dc304c4675c7dd1983c79bcb63292735681b6 Mon Sep 17 00:00:00 2001 From: Glenn Randers-Pehrson Date: Wed, 22 Feb 2012 08:29:19 -0600 Subject: [PATCH] [libpng15] Eliminated redundant png_push_read_tEXt|zTXt|iTXt|unknown code --- pngpread.c | 559 ++--------------------------------------------------- 1 file changed, 15 insertions(+), 544 deletions(-) diff --git a/pngpread.c b/pngpread.c index b3b6f693a..910733223 100644 --- a/pngpread.c +++ b/pngpread.c @@ -128,30 +128,6 @@ png_process_some_data(png_structp png_ptr, png_infop info_ptr) break; } -#ifdef PNG_READ_tEXt_SUPPORTED - case PNG_READ_tEXt_MODE: - { - png_push_read_tEXt(png_ptr, info_ptr); - break; - } - -#endif -#ifdef PNG_READ_zTXt_SUPPORTED - case PNG_READ_zTXt_MODE: - { - png_push_read_zTXt(png_ptr, info_ptr); - break; - } - -#endif -#ifdef 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); @@ -176,7 +152,7 @@ void /* PRIVATE */ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) { png_size_t num_checked = png_ptr->sig_bytes, - num_to_check = 8 - num_checked; + num_to_check = 8 - num_checked; if (png_ptr->buffer_size < num_to_check) { @@ -196,6 +172,7 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) else png_error(png_ptr, "PNG file corrupted by ASCII conversion"); } + else { if (png_ptr->sig_bytes >= 8) @@ -543,7 +520,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return; } - png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length); + png_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -556,7 +533,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return; } - png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length); + png_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -569,7 +546,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) return; } - png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length); + png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -580,7 +557,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); + png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); } png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; @@ -620,6 +597,7 @@ png_push_crc_finish(png_structp png_ptr) png_ptr->save_buffer_size -= save_size; png_ptr->save_buffer_ptr += save_size; } + if (png_ptr->skip_length && png_ptr->current_buffer_size) { png_size_t save_size = png_ptr->current_buffer_size; @@ -641,6 +619,7 @@ png_push_crc_finish(png_structp png_ptr) png_ptr->current_buffer_size -= save_size; png_ptr->current_buffer_ptr += save_size; } + if (!png_ptr->skip_length) { if (png_ptr->buffer_size < 4) @@ -663,6 +642,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) return; ptr = buffer; + if (png_ptr->save_buffer_size) { png_size_t save_size; @@ -680,6 +660,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) png_ptr->save_buffer_size -= save_size; png_ptr->save_buffer_ptr += save_size; } + if (length && png_ptr->current_buffer_size) { png_size_t save_size; @@ -709,6 +690,7 @@ png_push_save_buffer(png_structp png_ptr) png_bytep dp; istop = png_ptr->save_buffer_size; + for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer; i < istop; i++, sp++, dp++) { @@ -716,6 +698,7 @@ png_push_save_buffer(png_structp png_ptr) } } } + if (png_ptr->save_buffer_size + png_ptr->current_buffer_size > png_ptr->save_buffer_max) { @@ -742,6 +725,7 @@ png_push_save_buffer(png_structp png_ptr) png_free(png_ptr, old_buffer); png_ptr->save_buffer_max = new_max; } + if (png_ptr->current_buffer_size) { png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size, @@ -749,6 +733,7 @@ png_push_save_buffer(png_structp png_ptr) png_ptr->save_buffer_size += png_ptr->current_buffer_size; png_ptr->current_buffer_size = 0; } + png_ptr->save_buffer_ptr = png_ptr->save_buffer; png_ptr->buffer_size = 0; } @@ -850,6 +835,7 @@ png_push_read_IDAT(png_structp png_ptr) png_ptr->current_buffer_size -= save_size; png_ptr->current_buffer_ptr += save_size; } + if (!png_ptr->idat_size) { if (png_ptr->buffer_size < 4) @@ -1263,521 +1249,6 @@ png_read_push_finish_row(png_structp png_ptr) #endif /* PNG_READ_INTERLACING_SUPPORTED */ } -#ifdef PNG_READ_tEXt_SUPPORTED -void /* PRIVATE */ -png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 - length) -{ - if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) - { - PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */ - png_error(png_ptr, "Out of place tEXt"); - /* NOT REACHED */ - } - -#ifdef PNG_MAX_MALLOC_64K - png_ptr->skip_length = 0; /* This may not be necessary */ - - if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */ - { - png_warning(png_ptr, "tEXt chunk too large to fit in memory"); - png_ptr->skip_length = length - (png_uint_32)65535L; - length = (png_uint_32)65535L; - } -#endif - - png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1); - png_ptr->current_text[length] = '\0'; - png_ptr->current_text_ptr = png_ptr->current_text; - png_ptr->current_text_size = (png_size_t)length; - png_ptr->current_text_left = (png_size_t)length; - png_ptr->process_mode = PNG_READ_tEXt_MODE; -} - -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); - -#ifdef 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_sizeof(png_text)); - text_ptr->compression = PNG_TEXT_COMPRESSION_NONE; - text_ptr->key = key; - text_ptr->itxt_length = 0; - text_ptr->lang = NULL; - text_ptr->lang_key = NULL; - 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"); - } -} -#endif - -#ifdef PNG_READ_zTXt_SUPPORTED -void /* PRIVATE */ -png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 - length) -{ - if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) - { - PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */ - png_error(png_ptr, "Out of place zTXt"); - /* NOT REACHED */ - } - -#ifdef PNG_MAX_MALLOC_64K - /* We can't handle zTXt chunks > 64K, since we don't have enough space - * to be able to store the uncompressed data. Actually, the threshold - * is probably around 32K, but it isn't as definite as 64K is. - */ - if (length > (png_uint_32)65535L) - { - png_warning(png_ptr, "zTXt chunk too large to fit in memory"); - png_push_crc_skip(png_ptr, length); - return; - } -#endif - - png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1); - png_ptr->current_text[length] = '\0'; - png_ptr->current_text_ptr = png_ptr->current_text; - png_ptr->current_text_size = (png_size_t)length; - png_ptr->current_text_left = (png_size_t)length; - png_ptr->process_mode = PNG_READ_zTXt_MODE; -} - -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_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_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_sizeof(png_text)); - text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt; - text_ptr->key = key; - text_ptr->itxt_length = 0; - text_ptr->lang = NULL; - text_ptr->lang_key = NULL; - 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"); - } -} -#endif - -#ifdef PNG_READ_iTXt_SUPPORTED -void /* PRIVATE */ -png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 - length) -{ - if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) - { - PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */ - png_error(png_ptr, "Out of place iTXt"); - /* NOT REACHED */ - } - -#ifdef PNG_MAX_MALLOC_64K - png_ptr->skip_length = 0; /* This may not be necessary */ - - if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */ - { - png_warning(png_ptr, "iTXt chunk too large to fit in memory"); - png_ptr->skip_length = length - (png_uint_32)65535L; - length = (png_uint_32)65535L; - } -#endif - - png_ptr->current_text = (png_charp)png_malloc(png_ptr, length + 1); - png_ptr->current_text[length] = '\0'; - png_ptr->current_text_ptr = png_ptr->current_text; - png_ptr->current_text_size = (png_size_t)length; - png_ptr->current_text_left = (png_size_t)length; - png_ptr->process_mode = PNG_READ_iTXt_MODE; -} - -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); - -#ifdef 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_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"); - } -} -#endif - -/* 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_uint_32 chunk_name = png_ptr->chunk_name; - - if (PNG_CHUNK_CRITICAL(chunk_name)) - { -#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED - if (png_chunk_unknown_handling(png_ptr, chunk_name) != - PNG_HANDLE_CHUNK_ALWAYS -#ifdef PNG_READ_USER_CHUNKS_SUPPORTED - && png_ptr->read_user_chunk_fn == NULL -#endif - ) -#endif - png_chunk_error(png_ptr, "unknown critical chunk"); - - PNG_UNUSED(info_ptr) /* To quiet some compiler warnings */ - } - -#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED - /* TODO: the code below is apparently just using the - * png_struct::unknown_chunk member as a temporarily variable, it should be - * possible to eliminate both it and the temporary buffer. - */ - if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) - { -#ifdef PNG_MAX_MALLOC_64K - if (length > 65535) - { - png_warning(png_ptr, "unknown chunk too large to fit in memory"); - skip = length - 65535; - length = 65535; - } -#endif - /* This is just a record for the user; libpng doesn't use the character - * form of the name. - */ - PNG_CSTRING_FROM_CHUNK(png_ptr->unknown_chunk.name, png_ptr->chunk_name); - - png_ptr->unknown_chunk.size = length; - - if (length == 0) - png_ptr->unknown_chunk.data = NULL; - - else - { - png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, - png_ptr->unknown_chunk.size); - png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, - png_ptr->unknown_chunk.size); - } - -#ifdef 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_CHUNK_CRITICAL(png_ptr->chunk_name)) - if (png_chunk_unknown_handling(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 -#endif - png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1); - 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 /* PRIVATE */ png_push_have_info(png_structp png_ptr, png_infop info_ptr) {