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-rw-r--r--src/3rdparty/libpng/pngread.c1479
1 files changed, 1479 insertions, 0 deletions
diff --git a/src/3rdparty/libpng/pngread.c b/src/3rdparty/libpng/pngread.c
new file mode 100644
index 0000000..bd8bcd9
--- /dev/null
+++ b/src/3rdparty/libpng/pngread.c
@@ -0,0 +1,1479 @@
+
+/* pngread.c - read a PNG file
+ *
+ * Last changed in libpng 1.2.25 [February 18, 2008]
+ * For conditions of distribution and use, see copyright notice in png.h
+ * 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.)
+ *
+ * This file contains routines that an application calls directly to
+ * read a PNG file or stream.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_SUPPORTED)
+
+/* Create a PNG structure for reading, and allocate any memory needed. */
+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)
+{
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
+ warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
+}
+
+/* Alternate create PNG structure for reading, and allocate any memory needed. */
+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)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+ png_structp png_ptr;
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ jmp_buf jmpbuf;
+#endif
+#endif
+
+ int i;
+
+ png_debug(1, "in png_create_read_struct\n");
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
+ (png_malloc_ptr)malloc_fn, (png_voidp)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_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+#ifdef PNG_SETJMP_SUPPORTED
+#ifdef USE_FAR_KEYWORD
+ if (setjmp(jmpbuf))
+#else
+ if (setjmp(png_ptr->jmpbuf))
+#endif
+ {
+ 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);
+ }
+#ifdef USE_FAR_KEYWORD
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#endif
+#endif
+
+#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);
+
+ if(user_png_ver)
+ {
+ i=0;
+ do
+ {
+ if(user_png_ver[i] != png_libpng_ver[i])
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+ } while (png_libpng_ver[i++]);
+ }
+ else
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+
+
+ if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
+ {
+ /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
+ * we must recompile any applications that use any older library version.
+ * For versions after libpng 1.0, we will be compatible, so we need
+ * only check the first digit.
+ */
+ if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
+ (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
+ (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
+ {
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ char msg[80];
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+#endif
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "Incompatible libpng version in application and library");
+ }
+ }
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+ png_ptr->zstream.zalloc = png_zalloc;
+ png_ptr->zstream.zfree = png_zfree;
+ png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+ switch (inflateInit(&png_ptr->zstream))
+ {
+ case Z_OK: /* Do nothing */ break;
+ case Z_MEM_ERROR:
+ case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
+ case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
+ default: png_error(png_ptr, "Unknown zlib error");
+ }
+
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+
+#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(jmpbuf))
+ PNG_ABORT();
+ png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
+#else
+ if (setjmp(png_ptr->jmpbuf))
+ PNG_ABORT();
+#endif
+#endif
+ return (png_ptr);
+}
+
+#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
+/* Initialize PNG structure for reading, and allocate any memory needed.
+ This interface is deprecated in favour of the png_create_read_struct(),
+ and it will disappear as of libpng-1.3.0. */
+#undef png_read_init
+void PNGAPI
+png_read_init(png_structp png_ptr)
+{
+ /* We only come here via pre-1.0.7-compiled applications */
+ png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
+}
+
+void PNGAPI
+png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size, png_size_t png_info_size)
+{
+ /* We only come here via pre-1.0.12-compiled applications */
+ if(png_ptr == NULL) return;
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
+ if(png_sizeof(png_struct) > png_struct_size ||
+ png_sizeof(png_info) > png_info_size)
+ {
+ char msg[80];
+ png_ptr->warning_fn=NULL;
+ if (user_png_ver)
+ {
+ png_snprintf(msg, 80,
+ "Application was compiled with png.h from libpng-%.20s",
+ user_png_ver);
+ png_warning(png_ptr, msg);
+ }
+ png_snprintf(msg, 80,
+ "Application is running with png.c from libpng-%.20s",
+ png_libpng_ver);
+ png_warning(png_ptr, msg);
+ }
+#endif
+ if(png_sizeof(png_struct) > png_struct_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The png struct allocated by the application for reading is too small.");
+ }
+ if(png_sizeof(png_info) > png_info_size)
+ {
+ png_ptr->error_fn=NULL;
+#ifdef PNG_ERROR_NUMBERS_SUPPORTED
+ png_ptr->flags=0;
+#endif
+ png_error(png_ptr,
+ "The info struct allocated by application for reading is too small.");
+ }
+ png_read_init_3(&png_ptr, user_png_ver, png_struct_size);
+}
+#endif /* PNG_1_0_X || PNG_1_2_X */
+
+void PNGAPI
+png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
+ png_size_t png_struct_size)
+{
+#ifdef PNG_SETJMP_SUPPORTED
+ jmp_buf tmp_jmp; /* to save current jump buffer */
+#endif
+
+ int i=0;
+
+ png_structp png_ptr=*ptr_ptr;
+
+ if(png_ptr == NULL) return;
+
+ do
+ {
+ if(user_png_ver[i] != png_libpng_ver[i])
+ {
+#ifdef PNG_LEGACY_SUPPORTED
+ png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
+#else
+ png_ptr->warning_fn=NULL;
+ png_warning(png_ptr,
+ "Application uses deprecated png_read_init() and should be recompiled.");
+ break;
+#endif
+ }
+ } while (png_libpng_ver[i++]);
+
+ png_debug(1, "in png_read_init_3\n");
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* save jump buffer and error functions */
+ png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ if(png_sizeof(png_struct) > png_struct_size)
+ {
+ png_destroy_struct(png_ptr);
+ *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
+ png_ptr = *ptr_ptr;
+ }
+
+ /* reset all variables to 0 */
+ png_memset(png_ptr, 0, png_sizeof (png_struct));
+
+#ifdef PNG_SETJMP_SUPPORTED
+ /* restore jump buffer */
+ png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
+#endif
+
+ /* added at libpng-1.2.6 */
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+ png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
+ png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
+#endif
+
+ /* initialize zbuf - compression buffer */
+ png_ptr->zbuf_size = PNG_ZBUF_SIZE;
+ png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)png_ptr->zbuf_size);
+ png_ptr->zstream.zalloc = png_zalloc;
+ png_ptr->zstream.zfree = png_zfree;
+ png_ptr->zstream.opaque = (voidpf)png_ptr;
+
+ switch (inflateInit(&png_ptr->zstream))
+ {
+ case Z_OK: /* Do nothing */ break;
+ case Z_MEM_ERROR:
+ case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
+ case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
+ default: png_error(png_ptr, "Unknown zlib error");
+ }
+
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
+}
+
+#ifndef PNG_NO_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)
+{
+ if(png_ptr == NULL || info_ptr == NULL) return;
+ png_debug(1, "in png_read_info\n");
+ /* If we haven't checked all of the PNG signature bytes, do so now. */
+ if (png_ptr->sig_bytes < 8)
+ {
+ png_size_t num_checked = png_ptr->sig_bytes,
+ num_to_check = 8 - num_checked;
+
+ png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
+ png_ptr->sig_bytes = 8;
+
+ if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+ {
+ if (num_checked < 4 &&
+ png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+ png_error(png_ptr, "Not a PNG file");
+ else
+ png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+ }
+ if (num_checked < 3)
+ png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
+ }
+
+ for(;;)
+ {
+#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_sPLT_SUPPORTED)
+ PNG_CONST PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ PNG_CONST PNG_sRGB;
+#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 */
+ png_byte chunk_length[4];
+ png_uint_32 length;
+
+ png_read_data(png_ptr, chunk_length, 4);
+ 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_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name,
+ length);
+
+ /* This should be a binary subdivision search or a hash for
+ * matching the chunk name rather than a linear search.
+ */
+ 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))
+ png_handle_IHDR(png_ptr, info_ptr, length);
+ else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+ png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+ {
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ png_handle_unknown(png_ptr, info_ptr, 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");
+ break;
+ }
+ }
+#endif
+ 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_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");
+
+ png_ptr->idat_size = length;
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ break;
+ }
+#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_sCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+ png_handle_sCAL(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_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+ png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+ png_handle_sPLT(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
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+ png_handle_iTXt(png_ptr, info_ptr, length);
+#endif
+ else
+ png_handle_unknown(png_ptr, info_ptr, length);
+ }
+}
+#endif /* PNG_NO_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\n");
+ if(png_ptr == NULL) return;
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+ else
+ png_warning(png_ptr,
+ "Ignoring extra png_read_update_info() call; row buffer not reallocated");
+ png_read_transform_info(png_ptr, info_ptr);
+}
+
+#ifndef PNG_NO_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\n");
+ if(png_ptr == NULL) return;
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+void PNGAPI
+png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
+{
+#ifdef PNG_USE_LOCAL_ARRAYS
+ PNG_CONST PNG_IDAT;
+ PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
+ 0xff};
+ PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+#endif
+ int ret;
+ if(png_ptr == NULL) return;
+ png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
+ png_ptr->row_number, png_ptr->pass);
+ if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+ png_read_start_row(png_ptr);
+ 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
+ }
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ /* if interlaced and we do not need a new row, combine row and return */
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ 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,
+ png_pass_dsp_mask[png_ptr->pass]);
+ png_read_finish_row(png_ptr);
+ return;
+ }
+ break;
+ 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_ptr->irowbytes;
+ do
+ {
+ if (!(png_ptr->zstream.avail_in))
+ {
+ while (!png_ptr->idat_size)
+ {
+ png_byte chunk_length[4];
+
+ png_crc_finish(png_ptr, 0);
+
+ png_read_data(png_ptr, chunk_length, 4);
+ png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length);
+
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ 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_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);
+
+ png_ptr->row_info.color_type = png_ptr->color_type;
+ png_ptr->row_info.width = png_ptr->iwidth;
+ png_ptr->row_info.channels = png_ptr->channels;
+ 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_ROWBYTES(png_ptr->row_info.pixel_depth,
+ png_ptr->row_info.width);
+
+ if(png_ptr->row_buf[0])
+ png_read_filter_row(png_ptr, &(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+ (int)(png_ptr->row_buf[0]));
+
+ png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+ png_ptr->rowbytes + 1);
+
+#if defined(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(&(png_ptr->row_info), png_ptr->row_buf + 1);
+ }
+#endif
+
+
+ if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
+ png_do_read_transformations(png_ptr);
+
+#if defined(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)
+/* 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);
+
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row,
+ png_pass_dsp_mask[png_ptr->pass]);
+ if (row != NULL)
+ png_combine_row(png_ptr, row,
+ png_pass_mask[png_ptr->pass]);
+ }
+ else
+#endif
+ {
+ if (row != NULL)
+ png_combine_row(png_ptr, row, 0xff);
+ if (dsp_row != NULL)
+ png_combine_row(png_ptr, dsp_row, 0xff);
+ }
+ 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_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_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\n");
+ 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, png_bytep_NULL);
+ rp++;
+ }
+ else if(dp != NULL)
+ for (i = 0; i < num_rows; i++)
+ {
+ png_bytep dptr = *dp;
+ png_read_row(png_ptr, png_bytep_NULL, dptr);
+ dp++;
+ }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_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\n");
+ if(png_ptr == NULL) return;
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+ 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;
+ png_ptr->num_rows = image_height; /* Make sure this is set correctly */
+
+ for (j = 0; j < pass; j++)
+ {
+ rp = image;
+ for (i = 0; i < image_height; i++)
+ {
+ png_read_row(png_ptr, *rp, png_bytep_NULL);
+ rp++;
+ }
+ }
+}
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+
+#ifndef PNG_NO_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_byte chunk_length[4];
+ png_uint_32 length;
+
+ png_debug(1, "in png_read_end\n");
+ if(png_ptr == NULL) return;
+ png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
+
+ do
+ {
+#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_sPLT_SUPPORTED)
+ PNG_CONST PNG_sPLT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ PNG_CONST PNG_sRGB;
+#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 */
+
+ png_read_data(png_ptr, chunk_length, 4);
+ 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_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_IEND, 4))
+ png_handle_IEND(png_ptr, info_ptr, length);
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+ else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
+ {
+ if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+ png_error(png_ptr, "Too many IDAT's found");
+ }
+ png_handle_unknown(png_ptr, info_ptr, length);
+ if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_ptr->mode |= PNG_HAVE_PLTE;
+ }
+#endif
+ 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_HAVE_CHUNK_AFTER_IDAT))
+ png_error(png_ptr, "Too many IDAT's found");
+ png_crc_finish(png_ptr, length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ png_handle_PLTE(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_sCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
+ png_handle_sCAL(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_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ png_handle_sRGB(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_iCCP_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
+ png_handle_iCCP(png_ptr, info_ptr, length);
+#endif
+#if defined(PNG_READ_sPLT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
+ png_handle_sPLT(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
+#if defined(PNG_READ_iTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
+ 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_NO_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\n");
+ 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)
+ {
+#if defined(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)
+ {
+#if defined(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;
+ }
+
+#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;
+ png_error_ptr warning_fn;
+ png_voidp error_ptr;
+#ifdef PNG_USER_MEM_SUPPORTED
+ png_free_ptr free_fn;
+#endif
+
+ png_debug(1, "in png_read_destroy\n");
+ 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->big_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
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_PLTE)
+ png_zfree(png_ptr, png_ptr->palette);
+ png_ptr->free_me &= ~PNG_FREE_PLTE;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_PLTE)
+ png_zfree(png_ptr, png_ptr->palette);
+ png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
+#endif
+#if defined(PNG_tRNS_SUPPORTED) || \
+ defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_TRNS)
+ png_free(png_ptr, png_ptr->trans);
+ png_ptr->free_me &= ~PNG_FREE_TRNS;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_TRNS)
+ png_free(png_ptr, png_ptr->trans);
+ png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
+#endif
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+#ifdef PNG_FREE_ME_SUPPORTED
+ if (png_ptr->free_me & PNG_FREE_HIST)
+ png_free(png_ptr, png_ptr->hist);
+ png_ptr->free_me &= ~PNG_FREE_HIST;
+#else
+ if (png_ptr->flags & PNG_FLAG_FREE_HIST)
+ png_free(png_ptr, png_ptr->hist);
+ png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
+#endif
+#endif
+#if defined(PNG_READ_GAMMA_SUPPORTED)
+ if (png_ptr->gamma_16_table != NULL)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; i++)
+ {
+ png_free(png_ptr, png_ptr->gamma_16_table[i]);
+ }
+ png_free(png_ptr, png_ptr->gamma_16_table);
+ }
+#if defined(PNG_READ_BACKGROUND_SUPPORTED)
+ if (png_ptr->gamma_16_from_1 != NULL)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; 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)
+ {
+ int i;
+ int istop = (1 << (8 - png_ptr->gamma_shift));
+ for (i = 0; i < istop; i++)
+ {
+ png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
+ }
+ png_free(png_ptr, png_ptr->gamma_16_to_1);
+ }
+#endif
+#endif
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+ png_free(png_ptr, png_ptr->time_buffer);
+#endif
+
+ inflateEnd(&png_ptr->zstream);
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+ png_free(png_ptr, png_ptr->save_buffer);
+#endif
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+#ifdef PNG_TEXT_SUPPORTED
+ png_free(png_ptr, png_ptr->current_text);
+#endif /* PNG_TEXT_SUPPORTED */
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
+ /* 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->jmpbuf, png_sizeof (jmp_buf));
+#endif
+
+ error_fn = png_ptr->error_fn;
+ warning_fn = png_ptr->warning_fn;
+ 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;
+ png_ptr->warning_fn = warning_fn;
+ 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->jmpbuf, 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;
+}
+
+
+#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
+#if defined(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) return;
+#if defined(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
+
+ /* 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 ------------------- */
+
+#if defined(PNG_READ_16_TO_8_SUPPORTED)
+ /* tell libpng to strip 16 bit/color files down to 8 bits per color
+ */
+ if (transforms & PNG_TRANSFORM_STRIP_16)
+ png_set_strip_16(png_ptr);
+#endif
+
+#if defined(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
+
+#if defined(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
+
+#if defined(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 dithering.
+ */
+
+#if defined(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
+
+#if defined(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
+
+#if defined(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
+
+#if defined(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
+
+#if defined(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
+
+ /* We don't handle adding filler bytes */
+
+ /* 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 ------------------- */
+
+#ifdef PNG_FREE_ME_SUPPORTED
+ png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+#endif
+ if(info_ptr->row_pointers == NULL)
+ {
+ info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
+ info_ptr->height * png_sizeof(png_bytep));
+#ifdef PNG_FREE_ME_SUPPORTED
+ info_ptr->free_me |= PNG_FREE_ROWS;
+#endif
+ 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);
+
+ transforms = transforms; /* quiet compiler warnings */
+ params = params;
+
+}
+#endif /* PNG_INFO_IMAGE_SUPPORTED */
+#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED */