diff options
author | Peter Breitenlohner <peb@mppmu.mpg.de> | 2013-06-29 10:31:46 +0000 |
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committer | Peter Breitenlohner <peb@mppmu.mpg.de> | 2013-06-29 10:31:46 +0000 |
commit | 162739fb0e841def28075fc136c7337bd4b992eb (patch) | |
tree | c75fc22fc449d4b2df5639d06a05457314e40e9c /Build/source/libs/libpng/libpng-1.5.17/pngread.c | |
parent | 83196ba37bdc708ebfe9ea20fe0a397cb602cbf9 (diff) |
libpng 1.5.17
git-svn-id: svn://tug.org/texlive/trunk@31035 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Build/source/libs/libpng/libpng-1.5.17/pngread.c')
-rw-r--r-- | Build/source/libs/libpng/libpng-1.5.17/pngread.c | 1305 |
1 files changed, 1305 insertions, 0 deletions
diff --git a/Build/source/libs/libpng/libpng-1.5.17/pngread.c b/Build/source/libs/libpng/libpng-1.5.17/pngread.c new file mode 100644 index 00000000000..4296cf1cb66 --- /dev/null +++ b/Build/source/libs/libpng/libpng-1.5.17/pngread.c @@ -0,0 +1,1305 @@ + +/* pngread.c - read a PNG file + * + * Last changed in libpng 1.5.14 [January 24, 2013] + * Copyright (c) 1998-2012 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.) + * + * This code is released under the libpng license. + * For conditions of distribution and use, see the disclaimer + * and license in png.h + * + * This file contains routines that an application calls directly to + * read a PNG file or stream. + */ + +#include "pngpriv.h" + +#ifdef PNG_READ_SUPPORTED + +/* Create a PNG structure for reading, and allocate any memory needed. */ +PNG_FUNCTION(png_structp,PNGAPI +png_create_read_struct,(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn),PNG_ALLOCATED) +{ + +#ifdef PNG_USER_MEM_SUPPORTED + return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, + warn_fn, NULL, NULL, NULL)); +} + +/* Alternate create PNG structure for reading, and allocate any memory + * needed. + */ +PNG_FUNCTION(png_structp,PNGAPI +png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr, + png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, + png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED) +{ +#endif /* PNG_USER_MEM_SUPPORTED */ + +#ifdef PNG_SETJMP_SUPPORTED + volatile +#endif + png_structp png_ptr; + volatile int png_cleanup_needed = 0; + +#ifdef PNG_SETJMP_SUPPORTED +#ifdef USE_FAR_KEYWORD + jmp_buf tmp_jmpbuf; +#endif +#endif + + png_debug(1, "in png_create_read_struct"); + +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, + malloc_fn, mem_ptr); +#else + png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); +#endif + if (png_ptr == NULL) + return (NULL); + + /* Added at libpng-1.2.6 */ +#ifdef PNG_USER_LIMITS_SUPPORTED + png_ptr->user_width_max = PNG_USER_WIDTH_MAX; + png_ptr->user_height_max = PNG_USER_HEIGHT_MAX; + + /* Added at libpng-1.2.43 and 1.4.0 */ + png_ptr->user_chunk_cache_max = PNG_USER_CHUNK_CACHE_MAX; + + /* Added at libpng-1.2.43 and 1.4.1 */ + png_ptr->user_chunk_malloc_max = PNG_USER_CHUNK_MALLOC_MAX; +#endif + +#ifdef PNG_SETJMP_SUPPORTED +/* Applications that neglect to set up their own setjmp() and then + * encounter a png_error() will longjmp here. Since the jmpbuf is + * then meaningless we abort instead of returning. + */ +#ifdef USE_FAR_KEYWORD + if (setjmp(tmp_jmpbuf)) +#else + if (setjmp(png_jmpbuf(png_ptr))) /* Sets longjmp to match setjmp */ +#endif + PNG_ABORT(); +#ifdef USE_FAR_KEYWORD + png_memcpy(png_jmpbuf(png_ptr), tmp_jmpbuf, png_sizeof(jmp_buf)); +#endif +#endif /* PNG_SETJMP_SUPPORTED */ + +#ifdef PNG_USER_MEM_SUPPORTED + png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); +#endif + + png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); + + /* Call the general version checker (shared with read and write code): */ + if (!png_user_version_check(png_ptr, user_png_ver)) + png_cleanup_needed = 1; + + if (!png_cleanup_needed) + { + /* Initialize zbuf - compression buffer */ + png_ptr->zbuf_size = PNG_ZBUF_SIZE; + png_ptr->zbuf = (png_bytep)png_malloc_warn(png_ptr, png_ptr->zbuf_size); + + if (png_ptr->zbuf == NULL) + png_cleanup_needed = 1; + } + + png_ptr->zstream.zalloc = png_zalloc; + png_ptr->zstream.zfree = png_zfree; + png_ptr->zstream.opaque = (voidpf)png_ptr; + + if (!png_cleanup_needed) + { + switch (inflateInit(&png_ptr->zstream)) + { + case Z_OK: + break; /* Do nothing */ + + case Z_MEM_ERROR: + png_warning(png_ptr, "zlib memory error"); + png_cleanup_needed = 1; + break; + + case Z_STREAM_ERROR: + png_warning(png_ptr, "zlib stream error"); + png_cleanup_needed = 1; + break; + + case Z_VERSION_ERROR: + png_warning(png_ptr, "zlib version error"); + png_cleanup_needed = 1; + break; + + default: png_warning(png_ptr, "Unknown zlib error"); + png_cleanup_needed = 1; + } + } + + if (png_cleanup_needed) + { + /* Clean up PNG structure and deallocate any memory. */ + png_free(png_ptr, png_ptr->zbuf); + png_ptr->zbuf = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, + (png_free_ptr)free_fn, (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + return (NULL); + } + + png_ptr->zstream.next_out = png_ptr->zbuf; + png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; + + png_set_read_fn(png_ptr, NULL, NULL); + + + return (png_ptr); +} + + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the information before the actual image data. This has been + * changed in v0.90 to allow reading a file that already has the magic + * bytes read from the stream. You can tell libpng how many bytes have + * been read from the beginning of the stream (up to the maximum of 8) + * via png_set_sig_bytes(), and we will only check the remaining bytes + * here. The application can then have access to the signature bytes we + * read if it is determined that this isn't a valid PNG file. + */ +void PNGAPI +png_read_info(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_info"); + + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* Read and check the PNG file signature. */ + png_read_sig(png_ptr, info_ptr); + + for (;;) + { + png_uint_32 length = png_read_chunk_header(png_ptr); + png_uint_32 chunk_name = png_ptr->chunk_name; + + /* This should be a binary subdivision search or a hash for + * matching the chunk name rather than a linear search. + */ + if (chunk_name == png_IDAT) + if (png_ptr->mode & PNG_AFTER_IDAT) + png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; + + if (chunk_name == png_IHDR) + png_handle_IHDR(png_ptr, info_ptr, length); + + else if (chunk_name == png_IEND) + png_handle_IEND(png_ptr, info_ptr, length); + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_chunk_unknown_handling(png_ptr, chunk_name) != + PNG_HANDLE_CHUNK_AS_DEFAULT) + { + if (chunk_name == png_IDAT) + png_ptr->mode |= PNG_HAVE_IDAT; + + png_handle_unknown(png_ptr, info_ptr, length); + + if (chunk_name == png_PLTE) + png_ptr->mode |= PNG_HAVE_PLTE; + + else if (chunk_name == png_IDAT) + { + 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"); + + break; + } + } +#endif + else if (chunk_name == png_PLTE) + png_handle_PLTE(png_ptr, info_ptr, length); + + else if (chunk_name == png_IDAT) + { + 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"); + + png_ptr->idat_size = length; + png_ptr->mode |= PNG_HAVE_IDAT; + break; + } + +#ifdef PNG_READ_bKGD_SUPPORTED + else if (chunk_name == png_bKGD) + png_handle_bKGD(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_cHRM_SUPPORTED + else if (chunk_name == png_cHRM) + png_handle_cHRM(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_gAMA_SUPPORTED + else if (chunk_name == png_gAMA) + png_handle_gAMA(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_hIST_SUPPORTED + else if (chunk_name == png_hIST) + png_handle_hIST(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_oFFs_SUPPORTED + else if (chunk_name == png_oFFs) + png_handle_oFFs(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_pCAL_SUPPORTED + else if (chunk_name == png_pCAL) + png_handle_pCAL(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sCAL_SUPPORTED + else if (chunk_name == png_sCAL) + png_handle_sCAL(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_pHYs_SUPPORTED + else if (chunk_name == png_pHYs) + png_handle_pHYs(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sBIT_SUPPORTED + else if (chunk_name == png_sBIT) + png_handle_sBIT(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sRGB_SUPPORTED + else if (chunk_name == png_sRGB) + png_handle_sRGB(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_iCCP_SUPPORTED + else if (chunk_name == png_iCCP) + png_handle_iCCP(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sPLT_SUPPORTED + else if (chunk_name == png_sPLT) + png_handle_sPLT(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tEXt_SUPPORTED + else if (chunk_name == png_tEXt) + png_handle_tEXt(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tIME_SUPPORTED + else if (chunk_name == png_tIME) + png_handle_tIME(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tRNS_SUPPORTED + else if (chunk_name == png_tRNS) + png_handle_tRNS(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_zTXt_SUPPORTED + else if (chunk_name == png_zTXt) + png_handle_zTXt(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_iTXt_SUPPORTED + else if (chunk_name == png_iTXt) + png_handle_iTXt(png_ptr, info_ptr, length); +#endif + + else + png_handle_unknown(png_ptr, info_ptr, length); + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +/* Optional call to update the users info_ptr structure */ +void PNGAPI +png_read_update_info(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_update_info"); + + if (png_ptr == NULL) + return; + + png_read_start_row(png_ptr); + +#ifdef PNG_READ_TRANSFORMS_SUPPORTED + png_read_transform_info(png_ptr, info_ptr); +#else + PNG_UNUSED(info_ptr) +#endif +} + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Initialize palette, background, etc, after transformations + * are set, but before any reading takes place. This allows + * the user to obtain a gamma-corrected palette, for example. + * If the user doesn't call this, we will do it ourselves. + */ +void PNGAPI +png_start_read_image(png_structp png_ptr) +{ + png_debug(1, "in png_start_read_image"); + + if (png_ptr != NULL) + png_read_start_row(png_ptr); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +void PNGAPI +png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) +{ + int ret; + + png_row_info row_info; + + if (png_ptr == NULL) + return; + + png_debug2(1, "in png_read_row (row %lu, pass %d)", + (unsigned long)png_ptr->row_number, png_ptr->pass); + + /* png_read_start_row sets the information (in particular iwidth) for this + * interlace pass. + */ + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + png_read_start_row(png_ptr); + + /* 1.5.6: row_info moved out of png_struct to a local here. */ + row_info.width = png_ptr->iwidth; /* NOTE: width of current interlaced row */ + row_info.color_type = png_ptr->color_type; + row_info.bit_depth = png_ptr->bit_depth; + row_info.channels = png_ptr->channels; + row_info.pixel_depth = png_ptr->pixel_depth; + row_info.rowbytes = PNG_ROWBYTES(row_info.pixel_depth, row_info.width); + + 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 + } + +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* If interlaced and we do not need a new row, combine row and return. + * Notice that the pixels we have from previous rows have been transformed + * already; we can only combine like with like (transformed or + * untransformed) and, because of the libpng API for interlaced images, this + * means we must transform before de-interlacing. + */ + 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, 1/*display*/); + 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, 1/*display*/); + + 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)) + png_combine_row(png_ptr, dsp_row, 1/*display*/); + + png_read_finish_row(png_ptr); + return; + } + break; + + case 3: + if ((png_ptr->row_number & 3) || png_ptr->width < 3) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, 1/*display*/); + + png_read_finish_row(png_ptr); + return; + } + break; + + case 4: + if ((png_ptr->row_number & 3) != 2) + { + if (dsp_row != NULL && (png_ptr->row_number & 2)) + png_combine_row(png_ptr, dsp_row, 1/*display*/); + + png_read_finish_row(png_ptr); + return; + } + break; + case 5: + if ((png_ptr->row_number & 1) || png_ptr->width < 2) + { + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, 1/*display*/); + + png_read_finish_row(png_ptr); + return; + } + break; + + default: + case 6: + if (!(png_ptr->row_number & 1)) + { + png_read_finish_row(png_ptr); + return; + } + break; + } + } +#endif + + if (!(png_ptr->mode & PNG_HAVE_IDAT)) + png_error(png_ptr, "Invalid attempt to read row data"); + + png_ptr->zstream.next_out = png_ptr->row_buf; + png_ptr->zstream.avail_out = + (uInt)(PNG_ROWBYTES(png_ptr->pixel_depth, + png_ptr->iwidth) + 1); + + do + { + if (!(png_ptr->zstream.avail_in)) + { + while (!png_ptr->idat_size) + { + png_crc_finish(png_ptr, 0); + + png_ptr->idat_size = png_read_chunk_header(png_ptr); + if (png_ptr->chunk_name != png_IDAT) + png_error(png_ptr, "Not enough image data"); + } + png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; + png_ptr->zstream.next_in = png_ptr->zbuf; + if (png_ptr->zbuf_size > png_ptr->idat_size) + png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; + png_crc_read(png_ptr, png_ptr->zbuf, + (png_size_t)png_ptr->zstream.avail_in); + png_ptr->idat_size -= png_ptr->zstream.avail_in; + } + + ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); + + if (ret == Z_STREAM_END) + { + if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || + png_ptr->idat_size) + png_benign_error(png_ptr, "Extra compressed data"); + png_ptr->mode |= PNG_AFTER_IDAT; + png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; + break; + } + + if (ret != Z_OK) + png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : + "Decompression error"); + + } while (png_ptr->zstream.avail_out); + + if (png_ptr->row_buf[0] > PNG_FILTER_VALUE_NONE) + { + if (png_ptr->row_buf[0] < PNG_FILTER_VALUE_LAST) + png_read_filter_row(png_ptr, &row_info, png_ptr->row_buf + 1, + png_ptr->prev_row + 1, png_ptr->row_buf[0]); + else + png_error(png_ptr, "bad adaptive filter value"); + } + + /* libpng 1.5.6: the following line was copying png_ptr->rowbytes before + * 1.5.6, while the buffer really is this big in current versions of libpng + * it may not be in the future, so this was changed just to copy the + * interlaced count: + */ + png_memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1); + +#ifdef PNG_MNG_FEATURES_SUPPORTED + if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && + (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) + { + /* Intrapixel differencing */ + png_do_read_intrapixel(&row_info, png_ptr->row_buf + 1); + } +#endif + + +#ifdef PNG_READ_TRANSFORMS_SUPPORTED + if (png_ptr->transformations) + png_do_read_transformations(png_ptr, &row_info); +#endif + + /* The transformed pixel depth should match the depth now in row_info. */ + if (png_ptr->transformed_pixel_depth == 0) + { + png_ptr->transformed_pixel_depth = row_info.pixel_depth; + if (row_info.pixel_depth > png_ptr->maximum_pixel_depth) + png_error(png_ptr, "sequential row overflow"); + } + + else if (png_ptr->transformed_pixel_depth != row_info.pixel_depth) + png_error(png_ptr, "internal sequential row size calculation error"); + +#ifdef PNG_READ_INTERLACING_SUPPORTED + /* Blow up interlaced rows to full size */ + if (png_ptr->interlaced && + (png_ptr->transformations & PNG_INTERLACE)) + { + if (png_ptr->pass < 6) + png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass, + png_ptr->transformations); + + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, 1/*display*/); + + if (row != NULL) + png_combine_row(png_ptr, row, 0/*row*/); + } + + else +#endif + { + if (row != NULL) + png_combine_row(png_ptr, row, -1/*ignored*/); + + if (dsp_row != NULL) + png_combine_row(png_ptr, dsp_row, -1/*ignored*/); + } + png_read_finish_row(png_ptr); + + if (png_ptr->read_row_fn != NULL) + (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read one or more rows of image data. If the image is interlaced, + * and png_set_interlace_handling() has been called, the rows need to + * contain the contents of the rows from the previous pass. If the + * image has alpha or transparency, and png_handle_alpha()[*] has been + * called, the rows contents must be initialized to the contents of the + * screen. + * + * "row" holds the actual image, and pixels are placed in it + * as they arrive. If the image is displayed after each pass, it will + * appear to "sparkle" in. "display_row" can be used to display a + * "chunky" progressive image, with finer detail added as it becomes + * available. If you do not want this "chunky" display, you may pass + * NULL for display_row. If you do not want the sparkle display, and + * you have not called png_handle_alpha(), you may pass NULL for rows. + * If you have called png_handle_alpha(), and the image has either an + * alpha channel or a transparency chunk, you must provide a buffer for + * rows. In this case, you do not have to provide a display_row buffer + * also, but you may. If the image is not interlaced, or if you have + * not called png_set_interlace_handling(), the display_row buffer will + * be ignored, so pass NULL to it. + * + * [*] png_handle_alpha() does not exist yet, as of this version of libpng + */ + +void PNGAPI +png_read_rows(png_structp png_ptr, png_bytepp row, + png_bytepp display_row, png_uint_32 num_rows) +{ + png_uint_32 i; + png_bytepp rp; + png_bytepp dp; + + png_debug(1, "in png_read_rows"); + + if (png_ptr == NULL) + return; + + rp = row; + dp = display_row; + if (rp != NULL && dp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep rptr = *rp++; + png_bytep dptr = *dp++; + + png_read_row(png_ptr, rptr, dptr); + } + + else if (rp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep rptr = *rp; + png_read_row(png_ptr, rptr, NULL); + rp++; + } + + else if (dp != NULL) + for (i = 0; i < num_rows; i++) + { + png_bytep dptr = *dp; + png_read_row(png_ptr, NULL, dptr); + dp++; + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the entire image. If the image has an alpha channel or a tRNS + * chunk, and you have called png_handle_alpha()[*], you will need to + * initialize the image to the current image that PNG will be overlaying. + * We set the num_rows again here, in case it was incorrectly set in + * png_read_start_row() by a call to png_read_update_info() or + * png_start_read_image() if png_set_interlace_handling() wasn't called + * prior to either of these functions like it should have been. You can + * only call this function once. If you desire to have an image for + * each pass of a interlaced image, use png_read_rows() instead. + * + * [*] png_handle_alpha() does not exist yet, as of this version of libpng + */ +void PNGAPI +png_read_image(png_structp png_ptr, png_bytepp image) +{ + png_uint_32 i, image_height; + int pass, j; + png_bytepp rp; + + png_debug(1, "in png_read_image"); + + if (png_ptr == NULL) + return; + +#ifdef PNG_READ_INTERLACING_SUPPORTED + if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) + { + pass = png_set_interlace_handling(png_ptr); + /* And make sure transforms are initialized. */ + png_start_read_image(png_ptr); + } + else + { + if (png_ptr->interlaced && !(png_ptr->transformations & PNG_INTERLACE)) + { + /* Caller called png_start_read_image or png_read_update_info without + * first turning on the PNG_INTERLACE transform. We can fix this here, + * but the caller should do it! + */ + png_warning(png_ptr, "Interlace handling should be turned on when " + "using png_read_image"); + /* Make sure this is set correctly */ + png_ptr->num_rows = png_ptr->height; + } + + /* Obtain the pass number, which also turns on the PNG_INTERLACE flag in + * the above error case. + */ + pass = png_set_interlace_handling(png_ptr); + } +#else + if (png_ptr->interlaced) + png_error(png_ptr, + "Cannot read interlaced image -- interlace handler disabled"); + + pass = 1; +#endif + + image_height=png_ptr->height; + + for (j = 0; j < pass; j++) + { + rp = image; + for (i = 0; i < image_height; i++) + { + png_read_row(png_ptr, *rp, NULL); + rp++; + } + } +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +/* Read the end of the PNG file. Will not read past the end of the + * file, will verify the end is accurate, and will read any comments + * or time information at the end of the file, if info is not NULL. + */ +void PNGAPI +png_read_end(png_structp png_ptr, png_infop info_ptr) +{ + png_debug(1, "in png_read_end"); + + if (png_ptr == NULL) + return; + + png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ + +#ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED + /* Report invalid palette index; added at libng-1.5.10 */ + if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && + png_ptr->num_palette_max > png_ptr->num_palette) + png_benign_error(png_ptr, "Read palette index exceeding num_palette"); +#endif + + do + { + png_uint_32 length = png_read_chunk_header(png_ptr); + png_uint_32 chunk_name = png_ptr->chunk_name; + + if (chunk_name == png_IHDR) + png_handle_IHDR(png_ptr, info_ptr, length); + + else if (chunk_name == png_IEND) + png_handle_IEND(png_ptr, info_ptr, length); + +#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED + else if (png_chunk_unknown_handling(png_ptr, chunk_name) != + PNG_HANDLE_CHUNK_AS_DEFAULT) + { + if (chunk_name == png_IDAT) + { + if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + png_benign_error(png_ptr, "Too many IDATs found"); + } + png_handle_unknown(png_ptr, info_ptr, length); + if (chunk_name == png_PLTE) + png_ptr->mode |= PNG_HAVE_PLTE; + } +#endif + + else if (chunk_name == png_IDAT) + { + /* Zero length IDATs are legal after the last IDAT has been + * read, but not after other chunks have been read. + */ + if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) + png_benign_error(png_ptr, "Too many IDATs found"); + + png_crc_finish(png_ptr, length); + } + else if (chunk_name == png_PLTE) + png_handle_PLTE(png_ptr, info_ptr, length); + +#ifdef PNG_READ_bKGD_SUPPORTED + else if (chunk_name == png_bKGD) + png_handle_bKGD(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_cHRM_SUPPORTED + else if (chunk_name == png_cHRM) + png_handle_cHRM(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_gAMA_SUPPORTED + else if (chunk_name == png_gAMA) + png_handle_gAMA(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_hIST_SUPPORTED + else if (chunk_name == png_hIST) + png_handle_hIST(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_oFFs_SUPPORTED + else if (chunk_name == png_oFFs) + png_handle_oFFs(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_pCAL_SUPPORTED + else if (chunk_name == png_pCAL) + png_handle_pCAL(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sCAL_SUPPORTED + else if (chunk_name == png_sCAL) + png_handle_sCAL(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_pHYs_SUPPORTED + else if (chunk_name == png_pHYs) + png_handle_pHYs(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sBIT_SUPPORTED + else if (chunk_name == png_sBIT) + png_handle_sBIT(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sRGB_SUPPORTED + else if (chunk_name == png_sRGB) + png_handle_sRGB(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_iCCP_SUPPORTED + else if (chunk_name == png_iCCP) + png_handle_iCCP(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_sPLT_SUPPORTED + else if (chunk_name == png_sPLT) + png_handle_sPLT(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tEXt_SUPPORTED + else if (chunk_name == png_tEXt) + png_handle_tEXt(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tIME_SUPPORTED + else if (chunk_name == png_tIME) + png_handle_tIME(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_tRNS_SUPPORTED + else if (chunk_name == png_tRNS) + png_handle_tRNS(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_zTXt_SUPPORTED + else if (chunk_name == png_zTXt) + png_handle_zTXt(png_ptr, info_ptr, length); +#endif + +#ifdef PNG_READ_iTXt_SUPPORTED + else if (chunk_name == png_iTXt) + png_handle_iTXt(png_ptr, info_ptr, length); +#endif + + else + png_handle_unknown(png_ptr, info_ptr, length); + } while (!(png_ptr->mode & PNG_HAVE_IEND)); +} +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ + +/* Free all memory used by the read */ +void PNGAPI +png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, + png_infopp end_info_ptr_ptr) +{ + png_structp png_ptr = NULL; + png_infop info_ptr = NULL, end_info_ptr = NULL; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn = NULL; + png_voidp mem_ptr = NULL; +#endif + + png_debug(1, "in png_destroy_read_struct"); + + if (png_ptr_ptr != NULL) + png_ptr = *png_ptr_ptr; + if (png_ptr == NULL) + return; + +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; + mem_ptr = png_ptr->mem_ptr; +#endif + + if (info_ptr_ptr != NULL) + info_ptr = *info_ptr_ptr; + + if (end_info_ptr_ptr != NULL) + end_info_ptr = *end_info_ptr_ptr; + + png_read_destroy(png_ptr, info_ptr, end_info_ptr); + + if (info_ptr != NULL) + { +#ifdef PNG_TEXT_SUPPORTED + png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); +#endif + +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)info_ptr); +#endif + *info_ptr_ptr = NULL; + } + + if (end_info_ptr != NULL) + { +#ifdef PNG_READ_TEXT_SUPPORTED + png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); +#endif +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)end_info_ptr); +#endif + *end_info_ptr_ptr = NULL; + } + + if (png_ptr != NULL) + { +#ifdef PNG_USER_MEM_SUPPORTED + png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, + (png_voidp)mem_ptr); +#else + png_destroy_struct((png_voidp)png_ptr); +#endif + *png_ptr_ptr = NULL; + } +} + +/* Free all memory used by the read (old method) */ +void /* PRIVATE */ +png_read_destroy(png_structp png_ptr, png_infop info_ptr, + png_infop end_info_ptr) +{ +#ifdef PNG_SETJMP_SUPPORTED + jmp_buf tmp_jmp; +#endif + png_error_ptr error_fn; +#ifdef PNG_WARNINGS_SUPPORTED + png_error_ptr warning_fn; +#endif + png_voidp error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_free_ptr free_fn; +#endif + + png_debug(1, "in png_read_destroy"); + + if (info_ptr != NULL) + png_info_destroy(png_ptr, info_ptr); + + if (end_info_ptr != NULL) + png_info_destroy(png_ptr, end_info_ptr); + +#ifdef PNG_READ_GAMMA_SUPPORTED + png_destroy_gamma_table(png_ptr); +#endif + + png_free(png_ptr, png_ptr->zbuf); + png_free(png_ptr, png_ptr->big_row_buf); + png_free(png_ptr, png_ptr->big_prev_row); + png_free(png_ptr, png_ptr->chunkdata); + +#ifdef PNG_READ_QUANTIZE_SUPPORTED + png_free(png_ptr, png_ptr->palette_lookup); + png_free(png_ptr, png_ptr->quantize_index); +#endif + + if (png_ptr->free_me & PNG_FREE_PLTE) + png_zfree(png_ptr, png_ptr->palette); + png_ptr->free_me &= ~PNG_FREE_PLTE; + +#if defined(PNG_tRNS_SUPPORTED) || \ + defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) + if (png_ptr->free_me & PNG_FREE_TRNS) + png_free(png_ptr, png_ptr->trans_alpha); + png_ptr->free_me &= ~PNG_FREE_TRNS; +#endif + +#ifdef PNG_READ_hIST_SUPPORTED + if (png_ptr->free_me & PNG_FREE_HIST) + png_free(png_ptr, png_ptr->hist); + png_ptr->free_me &= ~PNG_FREE_HIST; +#endif + + inflateEnd(&png_ptr->zstream); + +#ifdef PNG_PROGRESSIVE_READ_SUPPORTED + png_free(png_ptr, png_ptr->save_buffer); +#endif + + /* Save the important info out of the png_struct, in case it is + * being used again. + */ +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(tmp_jmp, png_ptr->longjmp_buffer, png_sizeof(jmp_buf)); +#endif + + error_fn = png_ptr->error_fn; +#ifdef PNG_WARNINGS_SUPPORTED + warning_fn = png_ptr->warning_fn; +#endif + error_ptr = png_ptr->error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + free_fn = png_ptr->free_fn; +#endif + + png_memset(png_ptr, 0, png_sizeof(png_struct)); + + png_ptr->error_fn = error_fn; +#ifdef PNG_WARNINGS_SUPPORTED + png_ptr->warning_fn = warning_fn; +#endif + png_ptr->error_ptr = error_ptr; +#ifdef PNG_USER_MEM_SUPPORTED + png_ptr->free_fn = free_fn; +#endif + +#ifdef PNG_SETJMP_SUPPORTED + png_memcpy(png_ptr->longjmp_buffer, tmp_jmp, png_sizeof(jmp_buf)); +#endif + +} + +void PNGAPI +png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) +{ + if (png_ptr == NULL) + return; + + png_ptr->read_row_fn = read_row_fn; +} + + +#ifdef PNG_SEQUENTIAL_READ_SUPPORTED +#ifdef PNG_INFO_IMAGE_SUPPORTED +void PNGAPI +png_read_png(png_structp png_ptr, png_infop info_ptr, + int transforms, + voidp params) +{ + int row; + + if (png_ptr == NULL || info_ptr == NULL) + return; + + /* png_read_info() gives us all of the information from the + * PNG file before the first IDAT (image data chunk). + */ + png_read_info(png_ptr, info_ptr); + if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) + png_error(png_ptr, "Image is too high to process with png_read_png()"); + + /* -------------- image transformations start here ------------------- */ + +#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED + /* Tell libpng to strip 16-bit/color files down to 8 bits per color. + */ + if (transforms & PNG_TRANSFORM_SCALE_16) + { + /* Added at libpng-1.5.4. "strip_16" produces the same result that it + * did in earlier versions, while "scale_16" is now more accurate. + */ + png_set_scale_16(png_ptr); + } +#endif + +#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED + /* If both SCALE and STRIP are required pngrtran will effectively cancel the + * latter by doing SCALE first. This is ok and allows apps not to check for + * which is supported to get the right answer. + */ + if (transforms & PNG_TRANSFORM_STRIP_16) + png_set_strip_16(png_ptr); +#endif + +#ifdef PNG_READ_STRIP_ALPHA_SUPPORTED + /* Strip alpha bytes from the input data without combining with + * the background (not recommended). + */ + if (transforms & PNG_TRANSFORM_STRIP_ALPHA) + png_set_strip_alpha(png_ptr); +#endif + +#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) + /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single + * byte into separate bytes (useful for paletted and grayscale images). + */ + if (transforms & PNG_TRANSFORM_PACKING) + png_set_packing(png_ptr); +#endif + +#ifdef PNG_READ_PACKSWAP_SUPPORTED + /* Change the order of packed pixels to least significant bit first + * (not useful if you are using png_set_packing). + */ + if (transforms & PNG_TRANSFORM_PACKSWAP) + png_set_packswap(png_ptr); +#endif + +#ifdef PNG_READ_EXPAND_SUPPORTED + /* Expand paletted colors into true RGB triplets + * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel + * Expand paletted or RGB images with transparency to full alpha + * channels so the data will be available as RGBA quartets. + */ + if (transforms & PNG_TRANSFORM_EXPAND) + if ((png_ptr->bit_depth < 8) || + (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || + (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) + png_set_expand(png_ptr); +#endif + + /* We don't handle background color or gamma transformation or quantizing. + */ + +#ifdef PNG_READ_INVERT_SUPPORTED + /* Invert monochrome files to have 0 as white and 1 as black + */ + if (transforms & PNG_TRANSFORM_INVERT_MONO) + png_set_invert_mono(png_ptr); +#endif + +#ifdef PNG_READ_SHIFT_SUPPORTED + /* If you want to shift the pixel values from the range [0,255] or + * [0,65535] to the original [0,7] or [0,31], or whatever range the + * colors were originally in: + */ + if ((transforms & PNG_TRANSFORM_SHIFT) + && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) + { + png_color_8p sig_bit; + + png_get_sBIT(png_ptr, info_ptr, &sig_bit); + png_set_shift(png_ptr, sig_bit); + } +#endif + +#ifdef PNG_READ_BGR_SUPPORTED + /* Flip the RGB pixels to BGR (or RGBA to BGRA) */ + if (transforms & PNG_TRANSFORM_BGR) + png_set_bgr(png_ptr); +#endif + +#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED + /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */ + if (transforms & PNG_TRANSFORM_SWAP_ALPHA) + png_set_swap_alpha(png_ptr); +#endif + +#ifdef PNG_READ_SWAP_SUPPORTED + /* Swap bytes of 16-bit files to least significant byte first */ + if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) + png_set_swap(png_ptr); +#endif + +/* Added at libpng-1.2.41 */ +#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED + /* Invert the alpha channel from opacity to transparency */ + if (transforms & PNG_TRANSFORM_INVERT_ALPHA) + png_set_invert_alpha(png_ptr); +#endif + +/* Added at libpng-1.2.41 */ +#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED + /* Expand grayscale image to RGB */ + if (transforms & PNG_TRANSFORM_GRAY_TO_RGB) + png_set_gray_to_rgb(png_ptr); +#endif + +/* Added at libpng-1.5.4 */ +#ifdef PNG_READ_EXPAND_16_SUPPORTED + if (transforms & PNG_TRANSFORM_EXPAND_16) + png_set_expand_16(png_ptr); +#endif + + /* We don't handle adding filler bytes */ + + /* We use png_read_image and rely on that for interlace handling, but we also + * call png_read_update_info therefore must turn on interlace handling now: + */ + (void)png_set_interlace_handling(png_ptr); + + /* Optional call to gamma correct and add the background to the palette + * and update info structure. REQUIRED if you are expecting libpng to + * update the palette for you (i.e., you selected such a transform above). + */ + png_read_update_info(png_ptr, info_ptr); + + /* -------------- image transformations end here ------------------- */ + + png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); + if (info_ptr->row_pointers == NULL) + { + png_uint_32 iptr; + + info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, + info_ptr->height * png_sizeof(png_bytep)); + for (iptr=0; iptr<info_ptr->height; iptr++) + info_ptr->row_pointers[iptr] = NULL; + + info_ptr->free_me |= PNG_FREE_ROWS; + + for (row = 0; row < (int)info_ptr->height; row++) + info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, + png_get_rowbytes(png_ptr, info_ptr)); + } + + png_read_image(png_ptr, info_ptr->row_pointers); + info_ptr->valid |= PNG_INFO_IDAT; + + /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */ + png_read_end(png_ptr, info_ptr); + + PNG_UNUSED(transforms) /* Quiet compiler warnings */ + PNG_UNUSED(params) + +} +#endif /* PNG_INFO_IMAGE_SUPPORTED */ +#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ +#endif /* PNG_READ_SUPPORTED */ |