751 lines
25 KiB
C
751 lines
25 KiB
C
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/* pngread.c - read a PNG file
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libpng 1.0 beta 6 - version 0.96
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For conditions of distribution and use, see copyright notice in png.h
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Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
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Copyright (c) 1996, 1997 Andreas Dilger
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May 12, 1997
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*/
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#define PNG_INTERNAL
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#include "png.h"
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/* Create a PNG structure for reading, and allocate any memory needed. */
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png_structp
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png_create_read_struct(png_charp user_png_ver, png_voidp error_ptr,
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png_error_ptr error_fn, png_error_ptr warn_fn)
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{
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png_structp png_ptr;
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#ifdef USE_FAR_KEYWORD
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jmp_buf jmpbuf;
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#endif
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png_debug(1, "in png_create_read_struct\n");
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if ((png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG)) == NULL)
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{
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return (png_structp)NULL;
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}
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#ifdef USE_FAR_KEYWORD
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if (setjmp(jmpbuf))
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#else
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if (setjmp(png_ptr->jmpbuf))
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#endif
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{
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png_free(png_ptr, png_ptr->zbuf);
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png_destroy_struct(png_ptr);
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return (png_structp)NULL;
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}
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#ifdef USE_FAR_KEYWORD
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png_memcpy(png_ptr->jmpbuf,jmpbuf,sizeof(jmp_buf));
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#endif
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png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
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/* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
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* we must recompile any applications that use any older library version.
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* For versions after libpng 1.0, we will be compatible, so we need
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* only check the first digit.
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*/
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if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
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(user_png_ver[0] == '0' && user_png_ver[2] < '9'))
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{
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png_error(png_ptr,
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"Incompatible libpng version in application and library");
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}
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/* initialize zbuf - compression buffer */
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png_ptr->zbuf_size = PNG_ZBUF_SIZE;
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png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
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png_ptr->zstream.zalloc = png_zalloc;
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png_ptr->zstream.zfree = png_zfree;
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png_ptr->zstream.opaque = (voidpf)png_ptr;
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switch (inflateInit(&png_ptr->zstream))
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{
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case Z_OK: /* Do nothing */ break;
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case Z_MEM_ERROR:
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case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
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case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
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default: png_error(png_ptr, "Unknown zlib error");
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}
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png_ptr->zstream.next_out = png_ptr->zbuf;
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png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
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png_set_read_fn(png_ptr, NULL, NULL);
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return (png_ptr);
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}
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/* Initialize PNG structure for reading, and allocate any memory needed.
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This interface is depreciated in favour of the png_create_read_struct(),
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and it will eventually disappear. */
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void
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png_read_init(png_structp png_ptr)
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{
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jmp_buf tmp_jmp; /* to save current jump buffer */
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png_debug(1, "in png_read_init\n");
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/* save jump buffer and error functions */
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png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
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/* reset all variables to 0 */
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png_memset(png_ptr, 0, sizeof (png_struct));
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/* restore jump buffer */
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png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
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/* initialize zbuf - compression buffer */
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png_ptr->zbuf_size = PNG_ZBUF_SIZE;
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png_ptr->zbuf = png_malloc(png_ptr, png_ptr->zbuf_size);
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png_ptr->zstream.zalloc = png_zalloc;
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png_ptr->zstream.zfree = png_zfree;
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png_ptr->zstream.opaque = (voidpf)png_ptr;
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switch (inflateInit(&png_ptr->zstream))
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{
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case Z_OK: /* Do nothing */ break;
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case Z_MEM_ERROR:
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case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
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case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
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default: png_error(png_ptr, "Unknown zlib error");
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}
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png_ptr->zstream.next_out = png_ptr->zbuf;
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png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
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png_set_read_fn(png_ptr, NULL, NULL);
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}
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/* Read the information before the actual image data. This has been
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* changed in v0.90 to allow reading a file which already has the magic
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* bytes read from the stream. You can tell libpng how many bytes have
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* been read from the beginning of the stream (up to the maxumum of 8)
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* via png_set_sig_bytes(), and we will only check the remaining bytes
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* here. The application can then have access to the signature bytes we
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* read if it is determined that this isn't a valid PNG file.
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*/
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void
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png_read_info(png_structp png_ptr, png_infop info_ptr)
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{
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png_debug(1, "in png_read_info\n");
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/* save jump buffer and error functions */
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/* If we haven't checked all of the PNG signature bytes, do so now. */
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if (png_ptr->sig_bytes < 8)
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{
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png_size_t num_checked = png_ptr->sig_bytes,
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num_to_check = 8 - num_checked;
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png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
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png_ptr->sig_bytes = 8;
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if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
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{
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if (num_checked < 4 &&
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png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
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png_error(png_ptr, "Not a PNG file");
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else
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png_error(png_ptr, "PNG file corrupted by ASCII conversion");
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}
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}
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while (1)
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{
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png_byte chunk_length[4];
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png_uint_32 length;
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png_read_data(png_ptr, chunk_length, 4);
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length = png_get_uint_32(chunk_length);
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png_reset_crc(png_ptr);
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png_crc_read(png_ptr, png_ptr->chunk_name, 4);
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png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
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/* This should be a binary subdivision search or a hash for
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* matching the chunk name rather than a linear search.
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*/
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if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
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png_handle_IHDR(png_ptr, info_ptr, length);
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else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
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png_handle_PLTE(png_ptr, info_ptr, length);
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else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
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png_handle_IEND(png_ptr, info_ptr, length);
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else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
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{
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if (!(png_ptr->mode & PNG_HAVE_IHDR))
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png_error(png_ptr, "Missing IHDR before IDAT");
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else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
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!(png_ptr->mode & PNG_HAVE_PLTE))
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png_error(png_ptr, "Missing PLTE before IDAT");
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png_ptr->idat_size = length;
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png_ptr->mode |= PNG_HAVE_IDAT;
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break;
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}
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#if defined(PNG_READ_bKGD_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
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png_handle_bKGD(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_cHRM_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
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png_handle_cHRM(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_gAMA_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
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png_handle_gAMA(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_hIST_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
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png_handle_hIST(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_oFFs_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
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png_handle_oFFs(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_pCAL_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
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png_handle_pCAL(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_pHYs_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
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png_handle_pHYs(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_sBIT_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
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png_handle_sBIT(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_tEXt_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
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png_handle_tEXt(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_tIME_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
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png_handle_tIME(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_tRNS_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
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png_handle_tRNS(png_ptr, info_ptr, length);
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#endif
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#if defined(PNG_READ_zTXt_SUPPORTED)
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else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
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png_handle_zTXt(png_ptr, info_ptr, length);
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#endif
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else
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png_handle_unknown(png_ptr, info_ptr, length);
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}
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}
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/* optional call to update the users info_ptr structure */
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void
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png_read_update_info(png_structp png_ptr, png_infop info_ptr)
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{
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png_debug(1, "in png_read_update_info\n");
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/* save jump buffer and error functions */
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if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
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png_read_start_row(png_ptr);
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png_read_transform_info(png_ptr, info_ptr);
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}
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/* initialize palette, background, etc, after transformations
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are set, but before any reading takes place. This allows
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the user to obtail a gamma corrected palette, for example.
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If the user doesn't call this, we will do it ourselves. */
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void
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png_start_read_image(png_structp png_ptr)
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{
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png_debug(1, "in png_start_read_image\n");
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/* save jump buffer and error functions */
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if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
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png_read_start_row(png_ptr);
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}
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void
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png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
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{
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int ret;
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png_debug2(1, "in png_read_row (row %d, pass %d)\n",
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png_ptr->row_number, png_ptr->pass);
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/* save jump buffer and error functions */
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if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
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png_read_start_row(png_ptr);
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#if defined(PNG_READ_INTERLACING_SUPPORTED)
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/* if interlaced and we do not need a new row, combine row and return */
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if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
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{
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switch (png_ptr->pass)
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{
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case 0:
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if (png_ptr->row_number & 7)
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{
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 1:
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if ((png_ptr->row_number & 7) || png_ptr->width < 5)
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{
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 2:
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if ((png_ptr->row_number & 7) != 4)
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{
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if (dsp_row != NULL && (png_ptr->row_number & 4))
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 3:
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if ((png_ptr->row_number & 3) || png_ptr->width < 3)
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{
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 4:
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if ((png_ptr->row_number & 3) != 2)
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{
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if (dsp_row != NULL && (png_ptr->row_number & 2))
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 5:
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if ((png_ptr->row_number & 1) || png_ptr->width < 2)
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{
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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case 6:
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if (!(png_ptr->row_number & 1))
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{
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png_read_finish_row(png_ptr);
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return;
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}
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break;
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}
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}
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#endif
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if (!(png_ptr->mode & PNG_HAVE_IDAT))
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png_error(png_ptr, "Invalid attempt to read row data");
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png_ptr->zstream.next_out = png_ptr->row_buf;
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png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
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do
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{
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if (!(png_ptr->zstream.avail_in))
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{
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while (!png_ptr->idat_size)
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{
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png_byte chunk_length[4];
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png_crc_finish(png_ptr, 0);
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png_read_data(png_ptr, chunk_length, 4);
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png_ptr->idat_size = png_get_uint_32(chunk_length);
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png_reset_crc(png_ptr);
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png_crc_read(png_ptr, png_ptr->chunk_name, 4);
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if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
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png_error(png_ptr, "Not enough image data");
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}
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png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
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png_ptr->zstream.next_in = png_ptr->zbuf;
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if (png_ptr->zbuf_size > png_ptr->idat_size)
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png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
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png_crc_read(png_ptr, png_ptr->zbuf,
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(png_size_t)png_ptr->zstream.avail_in);
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png_ptr->idat_size -= png_ptr->zstream.avail_in;
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}
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ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
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if (ret == Z_STREAM_END)
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{
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if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
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png_ptr->idat_size)
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png_error(png_ptr, "Extra compressed data");
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png_ptr->mode |= PNG_AFTER_IDAT;
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png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
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break;
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}
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if (ret != Z_OK)
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png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
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"Decompression error");
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} while (png_ptr->zstream.avail_out);
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png_ptr->row_info.color_type = png_ptr->color_type;
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png_ptr->row_info.width = png_ptr->iwidth;
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png_ptr->row_info.channels = png_ptr->channels;
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png_ptr->row_info.bit_depth = png_ptr->bit_depth;
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png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
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png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
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(png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
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png_read_filter_row(png_ptr, &(png_ptr->row_info),
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png_ptr->row_buf + 1, png_ptr->prev_row + 1,
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(int)(png_ptr->row_buf[0]));
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png_memcpy(png_ptr->prev_row, png_ptr->row_buf, png_ptr->rowbytes + 1);
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if (png_ptr->transformations)
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png_do_read_transformations(png_ptr);
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#if defined(PNG_READ_INTERLACING_SUPPORTED)
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/* blow up interlaced rows to full size */
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if (png_ptr->interlaced &&
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(png_ptr->transformations & PNG_INTERLACE))
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{
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if (png_ptr->pass < 6)
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png_do_read_interlace(&(png_ptr->row_info),
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png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row,
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png_pass_dsp_mask[png_ptr->pass]);
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if (row != NULL)
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png_combine_row(png_ptr, row,
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png_pass_mask[png_ptr->pass]);
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}
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else
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#endif
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{
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if (row != NULL)
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png_combine_row(png_ptr, row, 0xff);
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if (dsp_row != NULL)
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png_combine_row(png_ptr, dsp_row, 0xff);
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}
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png_read_finish_row(png_ptr);
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}
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/* Read one or more rows of image data. If the image is interlaced,
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and png_set_interlace_handling() has been called, the rows need to
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to contain the contents of the rows from the previous pass. If
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the image has alpha or transparency, and png_handle_alpha() has been
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called, the rows contents must be initialized to the contents of the
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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. */
|
|
|
|
void
|
|
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\n");
|
|
/* save jump buffer and error functions */
|
|
rp = row;
|
|
dp = display_row;
|
|
for (i = 0; i < num_rows; i++)
|
|
{
|
|
png_bytep rptr;
|
|
png_bytep dptr;
|
|
|
|
if (rp != NULL)
|
|
rptr = *rp;
|
|
else
|
|
rptr = NULL;
|
|
if (dp != NULL)
|
|
dptr = *dp;
|
|
else
|
|
dptr = NULL;
|
|
png_read_row(png_ptr, rptr, dptr);
|
|
if (row != NULL)
|
|
rp++;
|
|
if (display_row != NULL)
|
|
dp++;
|
|
}
|
|
}
|
|
|
|
/* 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 */
|
|
void
|
|
png_read_image(png_structp png_ptr, png_bytepp image)
|
|
{
|
|
png_uint_32 i;
|
|
int pass, j;
|
|
png_bytepp rp;
|
|
|
|
png_debug(1, "in png_read_image\n");
|
|
/* save jump buffer and error functions */
|
|
pass = png_set_interlace_handling(png_ptr);
|
|
|
|
png_ptr->num_rows = png_ptr->height; /* Make sure this is set correctly */
|
|
|
|
for (j = 0; j < pass; j++)
|
|
{
|
|
rp = image;
|
|
for (i = 0; i < png_ptr->height; i++)
|
|
{
|
|
png_read_row(png_ptr, *rp, NULL);
|
|
rp++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* 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
|
|
png_read_end(png_structp png_ptr, png_infop info_ptr)
|
|
{
|
|
png_byte chunk_length[4];
|
|
png_uint_32 length;
|
|
|
|
png_debug(1, "in png_read_end\n");
|
|
/* save jump buffer and error functions */
|
|
png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
|
|
|
|
do
|
|
{
|
|
png_read_data(png_ptr, chunk_length, 4);
|
|
length = png_get_uint_32(chunk_length);
|
|
|
|
png_reset_crc(png_ptr);
|
|
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
|
|
|
|
png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
|
|
|
|
if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
|
|
png_handle_IHDR(png_ptr, info_ptr, length);
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
|
|
{
|
|
/* 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_AFTER_IDAT)
|
|
png_error(png_ptr, "Too many IDAT's found");
|
|
else
|
|
png_crc_finish(png_ptr, 0);
|
|
}
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
|
|
png_handle_PLTE(png_ptr, info_ptr, length);
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
|
|
png_handle_IEND(png_ptr, info_ptr, length);
|
|
#if defined(PNG_READ_bKGD_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
|
|
png_handle_bKGD(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_cHRM_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
|
|
png_handle_cHRM(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_gAMA_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
|
|
png_handle_gAMA(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_hIST_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
|
|
png_handle_hIST(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_oFFs_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
|
|
png_handle_oFFs(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_pCAL_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
|
|
png_handle_pCAL(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_pHYs_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
|
|
png_handle_pHYs(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_sBIT_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
|
|
png_handle_sBIT(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_tEXt_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
|
|
png_handle_tEXt(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_tIME_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
|
|
png_handle_tIME(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_tRNS_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
|
|
png_handle_tRNS(png_ptr, info_ptr, length);
|
|
#endif
|
|
#if defined(PNG_READ_zTXt_SUPPORTED)
|
|
else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
|
|
png_handle_zTXt(png_ptr, info_ptr, length);
|
|
#endif
|
|
else
|
|
png_handle_unknown(png_ptr, info_ptr, length);
|
|
} while (!(png_ptr->mode & PNG_HAVE_IEND));
|
|
}
|
|
|
|
/* free all memory used by the read */
|
|
void
|
|
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;
|
|
|
|
png_debug(1, "in png_destroy_read_struct\n");
|
|
/* save jump buffer and error functions */
|
|
if (png_ptr_ptr != NULL)
|
|
png_ptr = *png_ptr_ptr;
|
|
|
|
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)
|
|
{
|
|
png_destroy_struct((png_voidp)info_ptr);
|
|
*info_ptr_ptr = (png_infop)NULL;
|
|
}
|
|
|
|
if (end_info_ptr != NULL)
|
|
{
|
|
png_destroy_struct((png_voidp)end_info_ptr);
|
|
*end_info_ptr_ptr = (png_infop)NULL;
|
|
}
|
|
|
|
if (png_ptr != NULL)
|
|
{
|
|
png_destroy_struct((png_voidp)png_ptr);
|
|
*png_ptr_ptr = (png_structp)NULL;
|
|
}
|
|
}
|
|
|
|
/* free all memory used by the read (old method) */
|
|
void
|
|
png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
|
|
{
|
|
int i;
|
|
jmp_buf tmp_jmp;
|
|
png_error_ptr error_fn;
|
|
png_error_ptr warning_fn;
|
|
png_voidp error_ptr;
|
|
|
|
png_debug(1, "in png_read_destroy\n");
|
|
/* save jump buffer and error functions */
|
|
if (info_ptr != NULL)
|
|
png_info_destroy(png_ptr, info_ptr);
|
|
|
|
if (end_info_ptr != NULL)
|
|
png_info_destroy(png_ptr, end_info_ptr);
|
|
|
|
png_free(png_ptr, png_ptr->zbuf);
|
|
png_free(png_ptr, png_ptr->row_buf);
|
|
png_free(png_ptr, png_ptr->prev_row);
|
|
#if defined(PNG_READ_DITHER_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->palette_lookup);
|
|
png_free(png_ptr, png_ptr->dither_index);
|
|
#endif
|
|
#if defined(PNG_READ_GAMMA_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_table);
|
|
#endif
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_from_1);
|
|
png_free(png_ptr, png_ptr->gamma_to_1);
|
|
#endif
|
|
if (png_ptr->flags & PNG_FLAG_FREE_PALETTE)
|
|
png_free(png_ptr, png_ptr->palette);
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED) && defined(PNG_READ_bKGD_SUPPORTED)
|
|
if (png_ptr->flags & PNG_FLAG_FREE_TRANS)
|
|
png_free(png_ptr, png_ptr->trans);
|
|
#endif
|
|
#if defined(PNG_READ_hIST_SUPPORTED)
|
|
if (png_ptr->flags & PNG_FLAG_FREE_HIST)
|
|
png_free(png_ptr, png_ptr->hist);
|
|
#endif
|
|
#if defined(PNG_READ_GAMMA_SUPPORTED)
|
|
if (png_ptr->gamma_16_table != NULL)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_table[i]);
|
|
}
|
|
}
|
|
#endif
|
|
#if defined(PNG_READ_BACKGROUND_SUPPORTED)
|
|
png_free(png_ptr, png_ptr->gamma_16_table);
|
|
if (png_ptr->gamma_16_from_1 != NULL)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
|
|
}
|
|
}
|
|
png_free(png_ptr, png_ptr->gamma_16_from_1);
|
|
if (png_ptr->gamma_16_to_1 != NULL)
|
|
{
|
|
for (i = 0; i < (1 << (8 - png_ptr->gamma_shift)); i++)
|
|
{
|
|
png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
|
|
}
|
|
}
|
|
png_free(png_ptr, png_ptr->gamma_16_to_1);
|
|
#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.
|
|
*/
|
|
png_memcpy(tmp_jmp, png_ptr->jmpbuf, sizeof (jmp_buf));
|
|
|
|
error_fn = png_ptr->error_fn;
|
|
warning_fn = png_ptr->warning_fn;
|
|
error_ptr = png_ptr->error_ptr;
|
|
|
|
png_memset(png_ptr, 0, sizeof (png_struct));
|
|
|
|
png_ptr->error_fn = error_fn;
|
|
png_ptr->warning_fn = warning_fn;
|
|
png_ptr->error_ptr = error_ptr;
|
|
|
|
png_memcpy(png_ptr->jmpbuf, tmp_jmp, sizeof (jmp_buf));
|
|
}
|