X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/75b6e0a0aba793c6b739689b4414c1a2d8fcb041..960615f41009ac62e99f833afbec10d96bd2d2f9:/src/png/pngpread.c diff --git a/src/png/pngpread.c b/src/png/pngpread.c index b44651801d..b06fbadabd 100644 --- a/src/png/pngpread.c +++ b/src/png/pngpread.c @@ -1,22 +1,33 @@ /* pngpread.c - read a png file in push mode * - * libpng 1.0.3 - January 14, 1999 + * Last changed in libpng 1.2.32 [September 18, 2008] * For conditions of distribution and use, see copyright notice in png.h - * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. - * Copyright (c) 1996, 1997 Andreas Dilger - * Copyright (c) 1998, 1999 Glenn Randers-Pehrson + * Copyright (c) 1998-2008 Glenn Randers-Pehrson + * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) + * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) */ #define PNG_INTERNAL #include "png.h" - #ifdef PNG_PROGRESSIVE_READ_SUPPORTED -void +/* push model modes */ +#define PNG_READ_SIG_MODE 0 +#define PNG_READ_CHUNK_MODE 1 +#define PNG_READ_IDAT_MODE 2 +#define PNG_SKIP_MODE 3 +#define PNG_READ_tEXt_MODE 4 +#define PNG_READ_zTXt_MODE 5 +#define PNG_READ_DONE_MODE 6 +#define PNG_READ_iTXt_MODE 7 +#define PNG_ERROR_MODE 8 + +void PNGAPI png_process_data(png_structp png_ptr, png_infop info_ptr, png_bytep buffer, png_size_t buffer_size) { + if (png_ptr == NULL || info_ptr == NULL) return; png_push_restore_buffer(png_ptr, buffer, buffer_size); while (png_ptr->buffer_size) @@ -28,9 +39,10 @@ png_process_data(png_structp png_ptr, png_infop info_ptr, /* What we do with the incoming data depends on what we were previously * doing before we ran out of data... */ -void +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: @@ -61,6 +73,13 @@ png_process_some_data(png_structp png_ptr, png_infop info_ptr) 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: { @@ -81,7 +100,7 @@ png_process_some_data(png_structp png_ptr, png_infop info_ptr) * checked by the calling application, or because of multiple calls to this * routine. */ -void +void /* PRIVATE */ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) { png_size_t num_checked = png_ptr->sig_bytes, @@ -94,7 +113,7 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); - png_ptr->sig_bytes += num_to_check; + png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check); if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) { @@ -113,16 +132,73 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr) } } -void +void /* PRIVATE */ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) { +#ifdef PNG_USE_LOCAL_ARRAYS + PNG_CONST PNG_IHDR; + PNG_CONST PNG_IDAT; + PNG_CONST PNG_IEND; + PNG_CONST PNG_PLTE; +#if defined(PNG_READ_bKGD_SUPPORTED) + PNG_CONST PNG_bKGD; +#endif +#if defined(PNG_READ_cHRM_SUPPORTED) + PNG_CONST PNG_cHRM; +#endif +#if defined(PNG_READ_gAMA_SUPPORTED) + PNG_CONST PNG_gAMA; +#endif +#if defined(PNG_READ_hIST_SUPPORTED) + PNG_CONST PNG_hIST; +#endif +#if defined(PNG_READ_iCCP_SUPPORTED) + PNG_CONST PNG_iCCP; +#endif +#if defined(PNG_READ_iTXt_SUPPORTED) + PNG_CONST PNG_iTXt; +#endif +#if defined(PNG_READ_oFFs_SUPPORTED) + PNG_CONST PNG_oFFs; +#endif +#if defined(PNG_READ_pCAL_SUPPORTED) + PNG_CONST PNG_pCAL; +#endif +#if defined(PNG_READ_pHYs_SUPPORTED) + PNG_CONST PNG_pHYs; +#endif +#if defined(PNG_READ_sBIT_SUPPORTED) + PNG_CONST PNG_sBIT; +#endif +#if defined(PNG_READ_sCAL_SUPPORTED) + PNG_CONST PNG_sCAL; +#endif +#if defined(PNG_READ_sRGB_SUPPORTED) + PNG_CONST PNG_sRGB; +#endif +#if defined(PNG_READ_sPLT_SUPPORTED) + PNG_CONST PNG_sPLT; +#endif +#if defined(PNG_READ_tEXt_SUPPORTED) + PNG_CONST PNG_tEXt; +#endif +#if defined(PNG_READ_tIME_SUPPORTED) + PNG_CONST PNG_tIME; +#endif +#if defined(PNG_READ_tRNS_SUPPORTED) + PNG_CONST PNG_tRNS; +#endif +#if defined(PNG_READ_zTXt_SUPPORTED) + PNG_CONST PNG_zTXt; +#endif +#endif /* PNG_USE_LOCAL_ARRAYS */ /* First we make sure we have enough data for the 4 byte chunk name * and the 4 byte chunk length before proceeding with decoding the * chunk data. To fully decode each of these chunks, we also make * sure we have enough data in the buffer for the 4 byte CRC at the * end of every chunk (except IDAT, which is handled separately). */ - if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER)) + if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER)) { png_byte chunk_length[4]; @@ -133,30 +209,70 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) } png_push_fill_buffer(png_ptr, chunk_length, 4); - png_ptr->push_length = png_get_uint_32(chunk_length); + png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length); png_reset_crc(png_ptr); png_crc_read(png_ptr, png_ptr->chunk_name, 4); - png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER; + png_check_chunk_name(png_ptr, png_ptr->chunk_name); + png_ptr->mode |= PNG_HAVE_CHUNK_HEADER; } + if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + if (png_ptr->mode & PNG_AFTER_IDAT) + png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; + if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4)) { + if (png_ptr->push_length != 13) + png_error(png_ptr, "Invalid IHDR length"); if (png_ptr->push_length + 4 > png_ptr->buffer_size) { png_push_save_buffer(png_ptr); return; } - png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length); } - else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) + else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) { if (png_ptr->push_length + 4 > png_ptr->buffer_size) { png_push_save_buffer(png_ptr); return; } + png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length); + png_ptr->process_mode = PNG_READ_DONE_MODE; + png_push_have_end(png_ptr, info_ptr); + } +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + png_ptr->mode |= PNG_HAVE_IDAT; + png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); + if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) + png_ptr->mode |= PNG_HAVE_PLTE; + else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) + { + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + } + } +#endif + else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length); } else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) @@ -165,10 +281,17 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) * header chunks, and we can start reading the image (or if this * is called after the image has been read - we have an error). */ + if (!(png_ptr->mode & PNG_HAVE_IHDR)) + png_error(png_ptr, "Missing IHDR before IDAT"); + else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + !(png_ptr->mode & PNG_HAVE_PLTE)) + png_error(png_ptr, "Missing PLTE before IDAT"); + if (png_ptr->mode & PNG_HAVE_IDAT) { - if (png_ptr->push_length == 0) - return; + if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + if (png_ptr->push_length == 0) + return; if (png_ptr->mode & PNG_AFTER_IDAT) png_error(png_ptr, "Too many IDAT's found"); @@ -182,18 +305,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_ptr->zstream.next_out = png_ptr->row_buf; return; } - else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4)) - { - if (png_ptr->push_length + 4 > png_ptr->buffer_size) - { - png_push_save_buffer(png_ptr); - return; - } - - png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length); - png_ptr->process_mode = PNG_READ_DONE_MODE; - png_push_have_end(png_ptr, info_ptr); - } #if defined(PNG_READ_gAMA_SUPPORTED) else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4)) { @@ -202,7 +313,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -214,7 +324,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -226,7 +335,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -238,10 +346,31 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length); } #endif +#if defined(PNG_READ_iCCP_SUPPORTED) + else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length); + } +#endif +#if defined(PNG_READ_sPLT_SUPPORTED) + else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length); + } +#endif #if defined(PNG_READ_tRNS_SUPPORTED) else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4)) { @@ -250,7 +379,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -262,7 +390,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -274,7 +401,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -286,7 +412,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -298,7 +423,6 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length); } #endif @@ -310,10 +434,20 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length); } #endif +#if defined(PNG_READ_sCAL_SUPPORTED) + else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length); + } +#endif #if defined(PNG_READ_tIME_SUPPORTED) else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4)) { @@ -322,38 +456,63 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr) png_push_save_buffer(png_ptr); return; } - png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length); } #endif #if defined(PNG_READ_tEXt_SUPPORTED) else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4)) { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length); } #endif #if defined(PNG_READ_zTXt_SUPPORTED) else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4)) { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length); } +#endif +#if defined(PNG_READ_iTXt_SUPPORTED) + else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4)) + { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } + png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length); + } #endif else { + if (png_ptr->push_length + 4 > png_ptr->buffer_size) + { + png_push_save_buffer(png_ptr); + return; + } png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length); } - png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER; + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; } -void +void /* PRIVATE */ png_push_crc_skip(png_structp png_ptr, png_uint_32 skip) { png_ptr->process_mode = PNG_SKIP_MODE; png_ptr->skip_length = skip; } -void +void /* PRIVATE */ png_push_crc_finish(png_structp png_ptr) { if (png_ptr->skip_length && png_ptr->save_buffer_size) @@ -401,11 +560,12 @@ png_push_crc_finish(png_structp png_ptr) } } -void +void PNGAPI png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) { png_bytep ptr; + if (png_ptr == NULL) return; ptr = buffer; if (png_ptr->save_buffer_size) { @@ -439,14 +599,14 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length) } } -void +void /* PRIVATE */ png_push_save_buffer(png_structp png_ptr) { if (png_ptr->save_buffer_size) { if (png_ptr->save_buffer_ptr != png_ptr->save_buffer) { - png_size_t i,istop; + png_size_t i, istop; png_bytep sp; png_bytep dp; @@ -464,6 +624,11 @@ png_push_save_buffer(png_structp png_ptr) png_size_t new_max; png_bytep old_buffer; + if (png_ptr->save_buffer_size > PNG_SIZE_MAX - + (png_ptr->current_buffer_size + 256)) + { + png_error(png_ptr, "Potential overflow of save_buffer"); + } new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256; old_buffer = png_ptr->save_buffer; png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr, @@ -483,7 +648,7 @@ png_push_save_buffer(png_structp png_ptr) png_ptr->buffer_size = 0; } -void +void /* PRIVATE */ png_push_restore_buffer(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length) { @@ -493,10 +658,13 @@ png_push_restore_buffer(png_structp png_ptr, png_bytep buffer, png_ptr->current_buffer_ptr = png_ptr->current_buffer; } -void +void /* PRIVATE */ png_push_read_IDAT(png_structp png_ptr) { - if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER)) +#ifdef PNG_USE_LOCAL_ARRAYS + PNG_CONST PNG_IDAT; +#endif + if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER)) { png_byte chunk_length[4]; @@ -507,11 +675,10 @@ png_push_read_IDAT(png_structp png_ptr) } png_push_fill_buffer(png_ptr, chunk_length, 4); - png_ptr->push_length = png_get_uint_32(chunk_length); - + png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length); png_reset_crc(png_ptr); png_crc_read(png_ptr, png_ptr->chunk_name, 4); - png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER; + png_ptr->mode |= PNG_HAVE_CHUNK_HEADER; if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) { @@ -531,15 +698,15 @@ png_push_read_IDAT(png_structp png_ptr) { save_size = (png_size_t)png_ptr->idat_size; /* check for overflow */ - if((png_uint_32)save_size != png_ptr->idat_size) + if ((png_uint_32)save_size != png_ptr->idat_size) png_error(png_ptr, "save_size overflowed in pngpread"); } else save_size = png_ptr->save_buffer_size; png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size); - png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size); - + if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) + png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size); png_ptr->idat_size -= save_size; png_ptr->buffer_size -= save_size; png_ptr->save_buffer_size -= save_size; @@ -553,14 +720,15 @@ png_push_read_IDAT(png_structp png_ptr) { save_size = (png_size_t)png_ptr->idat_size; /* check for overflow */ - if((png_uint_32)save_size != png_ptr->idat_size) + if ((png_uint_32)save_size != png_ptr->idat_size) png_error(png_ptr, "save_size overflowed in pngpread"); } else save_size = png_ptr->current_buffer_size; png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size); - png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size); + if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) + png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size); png_ptr->idat_size -= save_size; png_ptr->buffer_size -= save_size; @@ -576,11 +744,12 @@ png_push_read_IDAT(png_structp png_ptr) } png_crc_finish(png_ptr, 0); - png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER; + png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER; + png_ptr->mode |= PNG_AFTER_IDAT; } } -void +void /* PRIVATE */ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length) { @@ -591,28 +760,43 @@ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_ptr->zstream.next_in = buffer; png_ptr->zstream.avail_in = (uInt)buffer_length; - for(;;) + for (;;) { ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); - if (ret == Z_STREAM_END) + if (ret != Z_OK) { - if (png_ptr->zstream.avail_in) - png_error(png_ptr, "Extra compressed data"); - if (!(png_ptr->zstream.avail_out)) + if (ret == Z_STREAM_END) { - png_push_process_row(png_ptr); - } + if (png_ptr->zstream.avail_in) + png_error(png_ptr, "Extra compressed data"); + if (!(png_ptr->zstream.avail_out)) + { + png_push_process_row(png_ptr); + } - png_ptr->mode |= PNG_AFTER_IDAT; - png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; - break; + png_ptr->mode |= PNG_AFTER_IDAT; + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } + else if (ret == Z_BUF_ERROR) + break; + else + png_error(png_ptr, "Decompression Error"); } - else if (ret == Z_BUF_ERROR) - break; - else if (ret != Z_OK) - png_error(png_ptr, "Decompression Error"); if (!(png_ptr->zstream.avail_out)) { + if (( +#if defined(PNG_READ_INTERLACING_SUPPORTED) + png_ptr->interlaced && png_ptr->pass > 6) || + (!png_ptr->interlaced && +#endif + png_ptr->row_number == png_ptr->num_rows)) + { + if (png_ptr->zstream.avail_in) + png_warning(png_ptr, "Too much data in IDAT chunks"); + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } png_push_process_row(png_ptr); png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; png_ptr->zstream.next_out = png_ptr->row_buf; @@ -622,7 +806,7 @@ png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, } } -void +void /* PRIVATE */ png_push_process_row(png_structp png_ptr) { png_ptr->row_info.color_type = png_ptr->color_type; @@ -631,8 +815,8 @@ png_push_process_row(png_structp png_ptr) png_ptr->row_info.bit_depth = png_ptr->bit_depth; png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; - png_ptr->row_info.rowbytes = ((png_ptr->row_info.width * - (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3); + png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, + png_ptr->row_info.width); png_read_filter_row(png_ptr, &(png_ptr->row_info), png_ptr->row_buf + 1, png_ptr->prev_row + 1, @@ -641,7 +825,7 @@ png_push_process_row(png_structp png_ptr) png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1); - if (png_ptr->transformations) + if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) png_do_read_transformations(png_ptr); #if defined(PNG_READ_INTERLACING_SUPPORTED) @@ -649,18 +833,42 @@ png_push_process_row(png_structp png_ptr) if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) { if (png_ptr->pass < 6) +/* old interface (pre-1.0.9): png_do_read_interlace(&(png_ptr->row_info), png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); + */ + png_do_read_interlace(png_ptr); - switch (png_ptr->pass) - { + switch (png_ptr->pass) + { case 0: { int i; for (i = 0; i < 8 && png_ptr->pass == 0; i++) { png_push_have_row(png_ptr, png_ptr->row_buf + 1); - png_read_push_finish_row(png_ptr); + png_read_push_finish_row(png_ptr); /* updates png_ptr->pass */ + } + if (png_ptr->pass == 2) /* pass 1 might be empty */ + { + for (i = 0; i < 4 && png_ptr->pass == 2; i++) + { + png_push_have_row(png_ptr, png_bytep_NULL); + png_read_push_finish_row(png_ptr); + } + } + if (png_ptr->pass == 4 && png_ptr->height <= 4) + { + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, png_bytep_NULL); + png_read_push_finish_row(png_ptr); + } + } + if (png_ptr->pass == 6 && png_ptr->height <= 4) + { + png_push_have_row(png_ptr, png_bytep_NULL); + png_read_push_finish_row(png_ptr); } break; } @@ -672,11 +880,11 @@ png_push_process_row(png_structp png_ptr) png_push_have_row(png_ptr, png_ptr->row_buf + 1); png_read_push_finish_row(png_ptr); } - if (png_ptr->pass == 2) + if (png_ptr->pass == 2) /* skip top 4 generated rows */ { for (i = 0; i < 4 && png_ptr->pass == 2; i++) { - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } } @@ -692,9 +900,17 @@ png_push_process_row(png_structp png_ptr) } for (i = 0; i < 4 && png_ptr->pass == 2; i++) { - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } + if (png_ptr->pass == 4) /* pass 3 might be empty */ + { + for (i = 0; i < 2 && png_ptr->pass == 4; i++) + { + png_push_have_row(png_ptr, png_bytep_NULL); + png_read_push_finish_row(png_ptr); + } + } break; } case 3: @@ -705,11 +921,11 @@ png_push_process_row(png_structp png_ptr) png_push_have_row(png_ptr, png_ptr->row_buf + 1); png_read_push_finish_row(png_ptr); } - if (png_ptr->pass == 4) + if (png_ptr->pass == 4) /* skip top two generated rows */ { for (i = 0; i < 2 && png_ptr->pass == 4; i++) { - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } } @@ -725,7 +941,12 @@ png_push_process_row(png_structp png_ptr) } for (i = 0; i < 2 && png_ptr->pass == 4; i++) { - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); + png_read_push_finish_row(png_ptr); + } + if (png_ptr->pass == 6) /* pass 5 might be empty */ + { + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } break; @@ -738,9 +959,9 @@ png_push_process_row(png_structp png_ptr) png_push_have_row(png_ptr, png_ptr->row_buf + 1); png_read_push_finish_row(png_ptr); } - if (png_ptr->pass == 6) + if (png_ptr->pass == 6) /* skip top generated row */ { - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } break; @@ -751,7 +972,7 @@ png_push_process_row(png_structp png_ptr) png_read_push_finish_row(png_ptr); if (png_ptr->pass != 6) break; - png_push_have_row(png_ptr, NULL); + png_push_have_row(png_ptr, png_bytep_NULL); png_read_push_finish_row(png_ptr); } } @@ -764,9 +985,30 @@ png_push_process_row(png_structp png_ptr) } } -void +void /* PRIVATE */ png_read_push_finish_row(png_structp png_ptr) { +#ifdef PNG_USE_LOCAL_ARRAYS + /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ + + /* start of interlace block */ + PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0}; + + /* offset to next interlace block */ + PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1}; + + /* start of interlace block in the y direction */ + PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1}; + + /* offset to next interlace block in the y direction */ + PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2}; + + /* Height of interlace block. This is not currently used - if you need + * it, uncomment it here and in png.h + PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1}; + */ +#endif + png_ptr->row_number++; if (png_ptr->row_number < png_ptr->num_rows) return; @@ -779,6 +1021,13 @@ png_read_push_finish_row(png_structp png_ptr) do { png_ptr->pass++; + if ((png_ptr->pass == 1 && png_ptr->width < 5) || + (png_ptr->pass == 3 && png_ptr->width < 3) || + (png_ptr->pass == 5 && png_ptr->width < 2)) + png_ptr->pass++; + + if (png_ptr->pass > 7) + png_ptr->pass--; if (png_ptr->pass >= 7) break; @@ -787,8 +1036,8 @@ png_read_push_finish_row(png_structp png_ptr) png_pass_start[png_ptr->pass]) / png_pass_inc[png_ptr->pass]; - png_ptr->irowbytes = ((png_ptr->iwidth * - png_ptr->pixel_depth + 7) >> 3) + 1; + png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1; if (png_ptr->transformations & PNG_INTERLACE) break; @@ -803,20 +1052,20 @@ png_read_push_finish_row(png_structp png_ptr) } #if defined(PNG_READ_tEXt_SUPPORTED) -void -png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +void /* PRIVATE */ +png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) { - if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND) + if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) { png_error(png_ptr, "Out of place tEXt"); - /* to quiet some compiler warnings */ - if(info_ptr == NULL) return; + info_ptr = info_ptr; /* to quiet some compiler warnings */ } #ifdef PNG_MAX_MALLOC_64K png_ptr->skip_length = 0; /* This may not be necessary */ - if (length > (png_uint_32)65535L) /* Can't hold the entire string in memory */ + 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; @@ -825,7 +1074,7 @@ png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length #endif png_ptr->current_text = (png_charp)png_malloc(png_ptr, - (png_uint_32)(length+1)); + (png_uint_32)(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; @@ -833,7 +1082,7 @@ png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length png_ptr->process_mode = PNG_READ_tEXt_MODE; } -void +void /* PRIVATE */ png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr) { if (png_ptr->buffer_size && png_ptr->current_text_left) @@ -853,6 +1102,7 @@ png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr) png_textp text_ptr; png_charp text; png_charp key; + int ret; if (png_ptr->buffer_size < 4) { @@ -868,35 +1118,44 @@ png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr) #endif key = png_ptr->current_text; - png_ptr->current_text = 0; for (text = key; *text; text++) /* empty loop */ ; - if (text != key + png_ptr->current_text_size) + if (text < key + png_ptr->current_text_size) text++; - text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_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; - png_set_text(png_ptr, info_ptr, text_ptr, 1); + 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 #if defined(PNG_READ_zTXt_SUPPORTED) -void -png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +void /* PRIVATE */ +png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) { - if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND) + if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND)) { png_error(png_ptr, "Out of place zTXt"); - /* to quiet some compiler warnings */ - if(info_ptr == NULL) return; + info_ptr = info_ptr; /* to quiet some compiler warnings */ } #ifdef PNG_MAX_MALLOC_64K @@ -913,7 +1172,7 @@ png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length #endif png_ptr->current_text = (png_charp)png_malloc(png_ptr, - (png_uint_32)(length+1)); + (png_uint_32)(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; @@ -921,7 +1180,7 @@ png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length png_ptr->process_mode = PNG_READ_zTXt_MODE; } -void +void /* PRIVATE */ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) { if (png_ptr->buffer_size && png_ptr->current_text_left) @@ -953,14 +1212,14 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) png_push_crc_finish(png_ptr); key = png_ptr->current_text; - png_ptr->current_text = 0; for (text = key; *text; text++) /* empty loop */ ; /* zTXt can't have zero text */ - if (text == key + png_ptr->current_text_size) + if (text >= key + png_ptr->current_text_size) { + png_ptr->current_text = NULL; png_free(png_ptr, key); return; } @@ -969,6 +1228,7 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */ { + png_ptr->current_text = NULL; png_free(png_ptr, key); return; } @@ -993,6 +1253,7 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) { 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; @@ -1002,8 +1263,8 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) 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_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); @@ -1017,8 +1278,8 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) 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_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, @@ -1046,64 +1307,251 @@ png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr) 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)sizeof(png_text)); + 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."); + } +} +#endif + +#if defined(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_error(png_ptr, "Out of place iTXt"); + info_ptr = info_ptr; /* to quiet some compiler warnings */ + } + +#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, + (png_uint_32)(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); + +#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); - png_set_text(png_ptr, info_ptr, text_ptr, 1); + 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. In the future we will have code here that can handle - * user-defined callback functions for unknown chunks before they are - * ignored or cause an error. 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. + * 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 -png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) +void /* PRIVATE */ +png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 + length) { - png_check_chunk_name(png_ptr, png_ptr->chunk_name); + png_uint_32 skip = 0; if (!(png_ptr->chunk_name[0] & 0x20)) { - png_chunk_error(png_ptr, "unknown critical chunk"); - /* to quiet some compiler warnings */ - if(info_ptr == NULL) return; +#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"); + + info_ptr = info_ptr; /* to quiet some compiler warnings */ } - png_push_crc_skip(png_ptr, length); +#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_memcpy((png_charp)png_ptr->unknown_chunk.name, + (png_charp)png_ptr->chunk_name, + png_sizeof(png_ptr->unknown_chunk.name)); + png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name) - 1] + = '\0'; + + png_ptr->unknown_chunk.size = (png_size_t)length; + if (length == 0) + png_ptr->unknown_chunk.data = NULL; + else + { + png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, + (png_uint_32)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 +#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 +void /* PRIVATE */ png_push_have_info(png_structp png_ptr, png_infop info_ptr) { if (png_ptr->info_fn != NULL) (*(png_ptr->info_fn))(png_ptr, info_ptr); } -void +void /* PRIVATE */ png_push_have_end(png_structp png_ptr, png_infop info_ptr) { if (png_ptr->end_fn != NULL) (*(png_ptr->end_fn))(png_ptr, info_ptr); } -void +void /* PRIVATE */ png_push_have_row(png_structp png_ptr, png_bytep row) { if (png_ptr->row_fn != NULL) @@ -1111,19 +1559,25 @@ png_push_have_row(png_structp png_ptr, png_bytep row) (int)png_ptr->pass); } -void +void PNGAPI png_progressive_combine_row (png_structp png_ptr, png_bytep old_row, png_bytep new_row) { +#ifdef PNG_USE_LOCAL_ARRAYS + PNG_CONST int FARDATA png_pass_dsp_mask[7] = + {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff}; +#endif + if (png_ptr == NULL) return; if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */ png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]); } -void +void PNGAPI png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr, png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn) { + if (png_ptr == NULL) return; png_ptr->info_fn = info_fn; png_ptr->row_fn = row_fn; png_ptr->end_fn = end_fn; @@ -1131,11 +1585,10 @@ png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr, png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer); } -png_voidp +png_voidp PNGAPI png_get_progressive_ptr(png_structp png_ptr) { + if (png_ptr == NULL) return (NULL); return png_ptr->io_ptr; } - #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ -