nuclear@2: 
nuclear@2: /* pngread.c - read a PNG file
nuclear@2:  *
nuclear@2:  * Last changed in libpng 1.2.30 [August 15, 2008]
nuclear@2:  * For conditions of distribution and use, see copyright notice in png.h
nuclear@2:  * Copyright (c) 1998-2008 Glenn Randers-Pehrson
nuclear@2:  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
nuclear@2:  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
nuclear@2:  *
nuclear@2:  * This file contains routines that an application calls directly to
nuclear@2:  * read a PNG file or stream.
nuclear@2:  */
nuclear@2: 
nuclear@2: #define PNG_INTERNAL
nuclear@2: #include "png.h"
nuclear@2: #if defined(PNG_READ_SUPPORTED)
nuclear@2: 
nuclear@2: /* Create a PNG structure for reading, and allocate any memory needed. */
nuclear@2: png_structp PNGAPI
nuclear@2: png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
nuclear@2:    png_error_ptr error_fn, png_error_ptr warn_fn)
nuclear@2: {
nuclear@2: 
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
nuclear@2:       warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
nuclear@2: }
nuclear@2: 
nuclear@2: /* Alternate create PNG structure for reading, and allocate any memory needed. */
nuclear@2: png_structp PNGAPI
nuclear@2: png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
nuclear@2:    png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
nuclear@2:    png_malloc_ptr malloc_fn, png_free_ptr free_fn)
nuclear@2: {
nuclear@2: #endif /* PNG_USER_MEM_SUPPORTED */
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    volatile
nuclear@2: #endif
nuclear@2:    png_structp png_ptr;
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2: #ifdef USE_FAR_KEYWORD
nuclear@2:    jmp_buf jmpbuf;
nuclear@2: #endif
nuclear@2: #endif
nuclear@2: 
nuclear@2:    int i;
nuclear@2: 
nuclear@2:    png_debug(1, "in png_create_read_struct\n");
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
nuclear@2:       (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
nuclear@2: #else
nuclear@2:    png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
nuclear@2: #endif
nuclear@2:    if (png_ptr == NULL)
nuclear@2:       return (NULL);
nuclear@2: 
nuclear@2:    /* added at libpng-1.2.6 */
nuclear@2: #ifdef PNG_SET_USER_LIMITS_SUPPORTED
nuclear@2:    png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
nuclear@2:    png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
nuclear@2: #endif
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2: #ifdef USE_FAR_KEYWORD
nuclear@2:    if (setjmp(jmpbuf))
nuclear@2: #else
nuclear@2:    if (setjmp(png_ptr->jmpbuf))
nuclear@2: #endif
nuclear@2:    {
nuclear@2:       png_free(png_ptr, png_ptr->zbuf);
nuclear@2:       png_ptr->zbuf = NULL;
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:       png_destroy_struct_2((png_voidp)png_ptr,
nuclear@2:          (png_free_ptr)free_fn, (png_voidp)mem_ptr);
nuclear@2: #else
nuclear@2:       png_destroy_struct((png_voidp)png_ptr);
nuclear@2: #endif
nuclear@2:       return (NULL);
nuclear@2:    }
nuclear@2: #ifdef USE_FAR_KEYWORD
nuclear@2:    png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf));
nuclear@2: #endif
nuclear@2: #endif
nuclear@2: 
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
nuclear@2: #endif
nuclear@2: 
nuclear@2:    png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
nuclear@2: 
nuclear@2:    if (user_png_ver)
nuclear@2:    {
nuclear@2:      i = 0;
nuclear@2:      do
nuclear@2:      {
nuclear@2:        if (user_png_ver[i] != png_libpng_ver[i])
nuclear@2:           png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
nuclear@2:      } while (png_libpng_ver[i++]);
nuclear@2:    }
nuclear@2:    else
nuclear@2:         png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
nuclear@2:    
nuclear@2: 
nuclear@2:    if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
nuclear@2:    {
nuclear@2:      /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
nuclear@2:       * we must recompile any applications that use any older library version.
nuclear@2:       * For versions after libpng 1.0, we will be compatible, so we need
nuclear@2:       * only check the first digit.
nuclear@2:       */
nuclear@2:      if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
nuclear@2:          (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
nuclear@2:          (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
nuclear@2:      {
nuclear@2: #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
nuclear@2:         char msg[80];
nuclear@2:         if (user_png_ver)
nuclear@2:         {
nuclear@2:           png_snprintf(msg, 80,
nuclear@2:              "Application was compiled with png.h from libpng-%.20s",
nuclear@2:              user_png_ver);
nuclear@2:           png_warning(png_ptr, msg);
nuclear@2:         }
nuclear@2:         png_snprintf(msg, 80,
nuclear@2:              "Application  is  running with png.c from libpng-%.20s",
nuclear@2:            png_libpng_ver);
nuclear@2:         png_warning(png_ptr, msg);
nuclear@2: #endif
nuclear@2: #ifdef PNG_ERROR_NUMBERS_SUPPORTED
nuclear@2:         png_ptr->flags = 0;
nuclear@2: #endif
nuclear@2:         png_error(png_ptr,
nuclear@2:            "Incompatible libpng version in application and library");
nuclear@2:      }
nuclear@2:    }
nuclear@2: 
nuclear@2:    /* initialize zbuf - compression buffer */
nuclear@2:    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
nuclear@2:    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
nuclear@2:      (png_uint_32)png_ptr->zbuf_size);
nuclear@2:    png_ptr->zstream.zalloc = png_zalloc;
nuclear@2:    png_ptr->zstream.zfree = png_zfree;
nuclear@2:    png_ptr->zstream.opaque = (voidpf)png_ptr;
nuclear@2: 
nuclear@2:    switch (inflateInit(&png_ptr->zstream))
nuclear@2:    {
nuclear@2:      case Z_OK: /* Do nothing */ break;
nuclear@2:      case Z_MEM_ERROR:
nuclear@2:      case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
nuclear@2:      case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
nuclear@2:      default: png_error(png_ptr, "Unknown zlib error");
nuclear@2:    }
nuclear@2: 
nuclear@2:    png_ptr->zstream.next_out = png_ptr->zbuf;
nuclear@2:    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
nuclear@2: 
nuclear@2:    png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2: /* Applications that neglect to set up their own setjmp() and then encounter
nuclear@2:    a png_error() will longjmp here.  Since the jmpbuf is then meaningless we
nuclear@2:    abort instead of returning. */
nuclear@2: #ifdef USE_FAR_KEYWORD
nuclear@2:    if (setjmp(jmpbuf))
nuclear@2:       PNG_ABORT();
nuclear@2:    png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf));
nuclear@2: #else
nuclear@2:    if (setjmp(png_ptr->jmpbuf))
nuclear@2:       PNG_ABORT();
nuclear@2: #endif
nuclear@2: #endif
nuclear@2:    return (png_ptr);
nuclear@2: }
nuclear@2: 
nuclear@2: #if defined(PNG_1_0_X) || defined(PNG_1_2_X)
nuclear@2: /* Initialize PNG structure for reading, and allocate any memory needed.
nuclear@2:    This interface is deprecated in favour of the png_create_read_struct(),
nuclear@2:    and it will disappear as of libpng-1.3.0. */
nuclear@2: #undef png_read_init
nuclear@2: void PNGAPI
nuclear@2: png_read_init(png_structp png_ptr)
nuclear@2: {
nuclear@2:    /* We only come here via pre-1.0.7-compiled applications */
nuclear@2:    png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
nuclear@2: }
nuclear@2: 
nuclear@2: void PNGAPI
nuclear@2: png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
nuclear@2:    png_size_t png_struct_size, png_size_t png_info_size)
nuclear@2: {
nuclear@2:    /* We only come here via pre-1.0.12-compiled applications */
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2: #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
nuclear@2:    if (png_sizeof(png_struct) > png_struct_size ||
nuclear@2:       png_sizeof(png_info) > png_info_size)
nuclear@2:    {
nuclear@2:       char msg[80];
nuclear@2:       png_ptr->warning_fn = NULL;
nuclear@2:       if (user_png_ver)
nuclear@2:       {
nuclear@2:         png_snprintf(msg, 80,
nuclear@2:            "Application was compiled with png.h from libpng-%.20s",
nuclear@2:            user_png_ver);
nuclear@2:         png_warning(png_ptr, msg);
nuclear@2:       }
nuclear@2:       png_snprintf(msg, 80,
nuclear@2:          "Application  is  running with png.c from libpng-%.20s",
nuclear@2:          png_libpng_ver);
nuclear@2:       png_warning(png_ptr, msg);
nuclear@2:    }
nuclear@2: #endif
nuclear@2:    if (png_sizeof(png_struct) > png_struct_size)
nuclear@2:      {
nuclear@2:        png_ptr->error_fn = NULL;
nuclear@2: #ifdef PNG_ERROR_NUMBERS_SUPPORTED
nuclear@2:        png_ptr->flags = 0;
nuclear@2: #endif
nuclear@2:        png_error(png_ptr,
nuclear@2:        "The png struct allocated by the application for reading is too small.");
nuclear@2:      }
nuclear@2:    if (png_sizeof(png_info) > png_info_size)
nuclear@2:      {
nuclear@2:        png_ptr->error_fn = NULL;
nuclear@2: #ifdef PNG_ERROR_NUMBERS_SUPPORTED
nuclear@2:        png_ptr->flags = 0;
nuclear@2: #endif
nuclear@2:        png_error(png_ptr,
nuclear@2:          "The info struct allocated by application for reading is too small.");
nuclear@2:      }
nuclear@2:    png_read_init_3(&png_ptr, user_png_ver, png_struct_size);
nuclear@2: }
nuclear@2: #endif /* PNG_1_0_X || PNG_1_2_X */
nuclear@2: 
nuclear@2: void PNGAPI
nuclear@2: png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
nuclear@2:    png_size_t png_struct_size)
nuclear@2: {
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    jmp_buf tmp_jmp;  /* to save current jump buffer */
nuclear@2: #endif
nuclear@2: 
nuclear@2:    int i = 0;
nuclear@2: 
nuclear@2:    png_structp png_ptr=*ptr_ptr;
nuclear@2: 
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2: 
nuclear@2:    do
nuclear@2:    {
nuclear@2:      if (user_png_ver[i] != png_libpng_ver[i])
nuclear@2:      {
nuclear@2: #ifdef PNG_LEGACY_SUPPORTED
nuclear@2:        png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
nuclear@2: #else
nuclear@2:        png_ptr->warning_fn = NULL;
nuclear@2:        png_warning(png_ptr,
nuclear@2:         "Application uses deprecated png_read_init() and should be recompiled.");
nuclear@2:        break;
nuclear@2: #endif
nuclear@2:      }
nuclear@2:    } while (png_libpng_ver[i++]);
nuclear@2: 
nuclear@2:    png_debug(1, "in png_read_init_3\n");
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    /* save jump buffer and error functions */
nuclear@2:    png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
nuclear@2: #endif
nuclear@2: 
nuclear@2:    if (png_sizeof(png_struct) > png_struct_size)
nuclear@2:    {
nuclear@2:       png_destroy_struct(png_ptr);
nuclear@2:       *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
nuclear@2:       png_ptr = *ptr_ptr;
nuclear@2:    }
nuclear@2: 
nuclear@2:    /* reset all variables to 0 */
nuclear@2:    png_memset(png_ptr, 0, png_sizeof(png_struct));
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    /* restore jump buffer */
nuclear@2:    png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
nuclear@2: #endif
nuclear@2: 
nuclear@2:    /* added at libpng-1.2.6 */
nuclear@2: #ifdef PNG_SET_USER_LIMITS_SUPPORTED
nuclear@2:    png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
nuclear@2:    png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
nuclear@2: #endif
nuclear@2: 
nuclear@2:    /* initialize zbuf - compression buffer */
nuclear@2:    png_ptr->zbuf_size = PNG_ZBUF_SIZE;
nuclear@2:    png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
nuclear@2:      (png_uint_32)png_ptr->zbuf_size);
nuclear@2:    png_ptr->zstream.zalloc = png_zalloc;
nuclear@2:    png_ptr->zstream.zfree = png_zfree;
nuclear@2:    png_ptr->zstream.opaque = (voidpf)png_ptr;
nuclear@2: 
nuclear@2:    switch (inflateInit(&png_ptr->zstream))
nuclear@2:    {
nuclear@2:      case Z_OK: /* Do nothing */ break;
nuclear@2:      case Z_MEM_ERROR:
nuclear@2:      case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
nuclear@2:      case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
nuclear@2:      default: png_error(png_ptr, "Unknown zlib error");
nuclear@2:    }
nuclear@2: 
nuclear@2:    png_ptr->zstream.next_out = png_ptr->zbuf;
nuclear@2:    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
nuclear@2: 
nuclear@2:    png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
nuclear@2: }
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: /* Read the information before the actual image data.  This has been
nuclear@2:  * changed in v0.90 to allow reading a file that already has the magic
nuclear@2:  * bytes read from the stream.  You can tell libpng how many bytes have
nuclear@2:  * been read from the beginning of the stream (up to the maximum of 8)
nuclear@2:  * via png_set_sig_bytes(), and we will only check the remaining bytes
nuclear@2:  * here.  The application can then have access to the signature bytes we
nuclear@2:  * read if it is determined that this isn't a valid PNG file.
nuclear@2:  */
nuclear@2: void PNGAPI
nuclear@2: png_read_info(png_structp png_ptr, png_infop info_ptr)
nuclear@2: {
nuclear@2:    if (png_ptr == NULL || info_ptr == NULL) return;
nuclear@2:    png_debug(1, "in png_read_info\n");
nuclear@2:    /* If we haven't checked all of the PNG signature bytes, do so now. */
nuclear@2:    if (png_ptr->sig_bytes < 8)
nuclear@2:    {
nuclear@2:       png_size_t num_checked = png_ptr->sig_bytes,
nuclear@2:                  num_to_check = 8 - num_checked;
nuclear@2: 
nuclear@2:       png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
nuclear@2:       png_ptr->sig_bytes = 8;
nuclear@2: 
nuclear@2:       if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
nuclear@2:       {
nuclear@2:          if (num_checked < 4 &&
nuclear@2:              png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
nuclear@2:             png_error(png_ptr, "Not a PNG file");
nuclear@2:          else
nuclear@2:             png_error(png_ptr, "PNG file corrupted by ASCII conversion");
nuclear@2:       }
nuclear@2:       if (num_checked < 3)
nuclear@2:          png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
nuclear@2:    }
nuclear@2: 
nuclear@2:    for (;;)
nuclear@2:    {
nuclear@2: #ifdef PNG_USE_LOCAL_ARRAYS
nuclear@2:       PNG_CONST PNG_IHDR;
nuclear@2:       PNG_CONST PNG_IDAT;
nuclear@2:       PNG_CONST PNG_IEND;
nuclear@2:       PNG_CONST PNG_PLTE;
nuclear@2: #if defined(PNG_READ_bKGD_SUPPORTED)
nuclear@2:       PNG_CONST PNG_bKGD;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_cHRM_SUPPORTED)
nuclear@2:       PNG_CONST PNG_cHRM;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_gAMA_SUPPORTED)
nuclear@2:       PNG_CONST PNG_gAMA;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_hIST_SUPPORTED)
nuclear@2:       PNG_CONST PNG_hIST;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iCCP_SUPPORTED)
nuclear@2:       PNG_CONST PNG_iCCP;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iTXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_iTXt;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_oFFs_SUPPORTED)
nuclear@2:       PNG_CONST PNG_oFFs;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pCAL_SUPPORTED)
nuclear@2:       PNG_CONST PNG_pCAL;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pHYs_SUPPORTED)
nuclear@2:       PNG_CONST PNG_pHYs;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sBIT_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sBIT;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sCAL_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sCAL;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sPLT_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sPLT;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sRGB_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sRGB;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tEXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tEXt;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tIME_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tIME;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tRNS_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tRNS;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_zTXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_zTXt;
nuclear@2: #endif
nuclear@2: #endif /* PNG_USE_LOCAL_ARRAYS */
nuclear@2:       png_uint_32 length = png_read_chunk_header(png_ptr);
nuclear@2:       PNG_CONST png_bytep chunk_name = png_ptr->chunk_name;
nuclear@2: 
nuclear@2:       /* This should be a binary subdivision search or a hash for
nuclear@2:        * matching the chunk name rather than a linear search.
nuclear@2:        */
nuclear@2:       if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:         if (png_ptr->mode & PNG_AFTER_IDAT)
nuclear@2:           png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
nuclear@2: 
nuclear@2:       if (!png_memcmp(chunk_name, png_IHDR, 4))
nuclear@2:          png_handle_IHDR(png_ptr, info_ptr, length);
nuclear@2:       else if (!png_memcmp(chunk_name, png_IEND, 4))
nuclear@2:          png_handle_IEND(png_ptr, info_ptr, length);
nuclear@2: #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
nuclear@2:       else if (png_handle_as_unknown(png_ptr, chunk_name))
nuclear@2:       {
nuclear@2:          if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:             png_ptr->mode |= PNG_HAVE_IDAT;
nuclear@2:          png_handle_unknown(png_ptr, info_ptr, length);
nuclear@2:          if (!png_memcmp(chunk_name, png_PLTE, 4))
nuclear@2:             png_ptr->mode |= PNG_HAVE_PLTE;
nuclear@2:          else if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:          {
nuclear@2:             if (!(png_ptr->mode & PNG_HAVE_IHDR))
nuclear@2:                png_error(png_ptr, "Missing IHDR before IDAT");
nuclear@2:             else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
nuclear@2:                      !(png_ptr->mode & PNG_HAVE_PLTE))
nuclear@2:                png_error(png_ptr, "Missing PLTE before IDAT");
nuclear@2:             break;
nuclear@2:          }
nuclear@2:       }
nuclear@2: #endif
nuclear@2:       else if (!png_memcmp(chunk_name, png_PLTE, 4))
nuclear@2:          png_handle_PLTE(png_ptr, info_ptr, length);
nuclear@2:       else if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:       {
nuclear@2:          if (!(png_ptr->mode & PNG_HAVE_IHDR))
nuclear@2:             png_error(png_ptr, "Missing IHDR before IDAT");
nuclear@2:          else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
nuclear@2:                   !(png_ptr->mode & PNG_HAVE_PLTE))
nuclear@2:             png_error(png_ptr, "Missing PLTE before IDAT");
nuclear@2: 
nuclear@2:          png_ptr->idat_size = length;
nuclear@2:          png_ptr->mode |= PNG_HAVE_IDAT;
nuclear@2:          break;
nuclear@2:       }
nuclear@2: #if defined(PNG_READ_bKGD_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_bKGD, 4))
nuclear@2:          png_handle_bKGD(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_cHRM_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_cHRM, 4))
nuclear@2:          png_handle_cHRM(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_gAMA_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_gAMA, 4))
nuclear@2:          png_handle_gAMA(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_hIST_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_hIST, 4))
nuclear@2:          png_handle_hIST(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_oFFs_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_oFFs, 4))
nuclear@2:          png_handle_oFFs(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pCAL_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_pCAL, 4))
nuclear@2:          png_handle_pCAL(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sCAL_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sCAL, 4))
nuclear@2:          png_handle_sCAL(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pHYs_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_pHYs, 4))
nuclear@2:          png_handle_pHYs(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sBIT_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sBIT, 4))
nuclear@2:          png_handle_sBIT(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sRGB_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sRGB, 4))
nuclear@2:          png_handle_sRGB(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iCCP_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_iCCP, 4))
nuclear@2:          png_handle_iCCP(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sPLT_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sPLT, 4))
nuclear@2:          png_handle_sPLT(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tEXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tEXt, 4))
nuclear@2:          png_handle_tEXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tIME_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tIME, 4))
nuclear@2:          png_handle_tIME(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tRNS_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tRNS, 4))
nuclear@2:          png_handle_tRNS(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_zTXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_zTXt, 4))
nuclear@2:          png_handle_zTXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iTXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_iTXt, 4))
nuclear@2:          png_handle_iTXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2:       else
nuclear@2:          png_handle_unknown(png_ptr, info_ptr, length);
nuclear@2:    }
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: /* optional call to update the users info_ptr structure */
nuclear@2: void PNGAPI
nuclear@2: png_read_update_info(png_structp png_ptr, png_infop info_ptr)
nuclear@2: {
nuclear@2:    png_debug(1, "in png_read_update_info\n");
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
nuclear@2:       png_read_start_row(png_ptr);
nuclear@2:    else
nuclear@2:       png_warning(png_ptr,
nuclear@2:       "Ignoring extra png_read_update_info() call; row buffer not reallocated");
nuclear@2:    png_read_transform_info(png_ptr, info_ptr);
nuclear@2: }
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: /* Initialize palette, background, etc, after transformations
nuclear@2:  * are set, but before any reading takes place.  This allows
nuclear@2:  * the user to obtain a gamma-corrected palette, for example.
nuclear@2:  * If the user doesn't call this, we will do it ourselves.
nuclear@2:  */
nuclear@2: void PNGAPI
nuclear@2: png_start_read_image(png_structp png_ptr)
nuclear@2: {
nuclear@2:    png_debug(1, "in png_start_read_image\n");
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
nuclear@2:       png_read_start_row(png_ptr);
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: void PNGAPI
nuclear@2: png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
nuclear@2: {
nuclear@2: #ifdef PNG_USE_LOCAL_ARRAYS
nuclear@2:    PNG_CONST PNG_IDAT;
nuclear@2:    PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
nuclear@2:       0xff};
nuclear@2:    PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
nuclear@2: #endif
nuclear@2:    int ret;
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
nuclear@2:       png_ptr->row_number, png_ptr->pass);
nuclear@2:    if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
nuclear@2:       png_read_start_row(png_ptr);
nuclear@2:    if (png_ptr->row_number == 0 && png_ptr->pass == 0)
nuclear@2:    {
nuclear@2:    /* check for transforms that have been set but were defined out */
nuclear@2: #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_INVERT_MONO)
nuclear@2:       png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_FILLER)
nuclear@2:       png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_PACKSWAP)
nuclear@2:       png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_PACK)
nuclear@2:       png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_SHIFT)
nuclear@2:       png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_BGR)
nuclear@2:       png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2: #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
nuclear@2:    if (png_ptr->transformations & PNG_SWAP_BYTES)
nuclear@2:       png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
nuclear@2: #endif
nuclear@2:    }
nuclear@2: 
nuclear@2: #if defined(PNG_READ_INTERLACING_SUPPORTED)
nuclear@2:    /* if interlaced and we do not need a new row, combine row and return */
nuclear@2:    if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
nuclear@2:    {
nuclear@2:       switch (png_ptr->pass)
nuclear@2:       {
nuclear@2:          case 0:
nuclear@2:             if (png_ptr->row_number & 0x07)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL)
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 1:
nuclear@2:             if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL)
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 2:
nuclear@2:             if ((png_ptr->row_number & 0x07) != 4)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL && (png_ptr->row_number & 4))
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 3:
nuclear@2:             if ((png_ptr->row_number & 3) || png_ptr->width < 3)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL)
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 4:
nuclear@2:             if ((png_ptr->row_number & 3) != 2)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL && (png_ptr->row_number & 2))
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 5:
nuclear@2:             if ((png_ptr->row_number & 1) || png_ptr->width < 2)
nuclear@2:             {
nuclear@2:                if (dsp_row != NULL)
nuclear@2:                   png_combine_row(png_ptr, dsp_row,
nuclear@2:                      png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:          case 6:
nuclear@2:             if (!(png_ptr->row_number & 1))
nuclear@2:             {
nuclear@2:                png_read_finish_row(png_ptr);
nuclear@2:                return;
nuclear@2:             }
nuclear@2:             break;
nuclear@2:       }
nuclear@2:    }
nuclear@2: #endif
nuclear@2: 
nuclear@2:    if (!(png_ptr->mode & PNG_HAVE_IDAT))
nuclear@2:       png_error(png_ptr, "Invalid attempt to read row data");
nuclear@2: 
nuclear@2:    png_ptr->zstream.next_out = png_ptr->row_buf;
nuclear@2:    png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
nuclear@2:    do
nuclear@2:    {
nuclear@2:       if (!(png_ptr->zstream.avail_in))
nuclear@2:       {
nuclear@2:          while (!png_ptr->idat_size)
nuclear@2:          {
nuclear@2:             png_crc_finish(png_ptr, 0);
nuclear@2: 
nuclear@2:             png_ptr->idat_size = png_read_chunk_header(png_ptr);
nuclear@2:             if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
nuclear@2:                png_error(png_ptr, "Not enough image data");
nuclear@2:          }
nuclear@2:          png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
nuclear@2:          png_ptr->zstream.next_in = png_ptr->zbuf;
nuclear@2:          if (png_ptr->zbuf_size > png_ptr->idat_size)
nuclear@2:             png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
nuclear@2:          png_crc_read(png_ptr, png_ptr->zbuf,
nuclear@2:             (png_size_t)png_ptr->zstream.avail_in);
nuclear@2:          png_ptr->idat_size -= png_ptr->zstream.avail_in;
nuclear@2:       }
nuclear@2:       ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
nuclear@2:       if (ret == Z_STREAM_END)
nuclear@2:       {
nuclear@2:          if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
nuclear@2:             png_ptr->idat_size)
nuclear@2:             png_error(png_ptr, "Extra compressed data");
nuclear@2:          png_ptr->mode |= PNG_AFTER_IDAT;
nuclear@2:          png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
nuclear@2:          break;
nuclear@2:       }
nuclear@2:       if (ret != Z_OK)
nuclear@2:          png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
nuclear@2:                    "Decompression error");
nuclear@2: 
nuclear@2:    } while (png_ptr->zstream.avail_out);
nuclear@2: 
nuclear@2:    png_ptr->row_info.color_type = png_ptr->color_type;
nuclear@2:    png_ptr->row_info.width = png_ptr->iwidth;
nuclear@2:    png_ptr->row_info.channels = png_ptr->channels;
nuclear@2:    png_ptr->row_info.bit_depth = png_ptr->bit_depth;
nuclear@2:    png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
nuclear@2:    png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
nuclear@2:        png_ptr->row_info.width);
nuclear@2: 
nuclear@2:    if (png_ptr->row_buf[0])
nuclear@2:    png_read_filter_row(png_ptr, &(png_ptr->row_info),
nuclear@2:       png_ptr->row_buf + 1, png_ptr->prev_row + 1,
nuclear@2:       (int)(png_ptr->row_buf[0]));
nuclear@2: 
nuclear@2:    png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
nuclear@2:       png_ptr->rowbytes + 1);
nuclear@2: 
nuclear@2: #if defined(PNG_MNG_FEATURES_SUPPORTED)
nuclear@2:    if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
nuclear@2:       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
nuclear@2:    {
nuclear@2:       /* Intrapixel differencing */
nuclear@2:       png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
nuclear@2:    }
nuclear@2: #endif
nuclear@2: 
nuclear@2: 
nuclear@2:    if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
nuclear@2:       png_do_read_transformations(png_ptr);
nuclear@2: 
nuclear@2: #if defined(PNG_READ_INTERLACING_SUPPORTED)
nuclear@2:    /* blow up interlaced rows to full size */
nuclear@2:    if (png_ptr->interlaced &&
nuclear@2:       (png_ptr->transformations & PNG_INTERLACE))
nuclear@2:    {
nuclear@2:       if (png_ptr->pass < 6)
nuclear@2: /*       old interface (pre-1.0.9):
nuclear@2:          png_do_read_interlace(&(png_ptr->row_info),
nuclear@2:             png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
nuclear@2:  */
nuclear@2:          png_do_read_interlace(png_ptr);
nuclear@2: 
nuclear@2:       if (dsp_row != NULL)
nuclear@2:          png_combine_row(png_ptr, dsp_row,
nuclear@2:             png_pass_dsp_mask[png_ptr->pass]);
nuclear@2:       if (row != NULL)
nuclear@2:          png_combine_row(png_ptr, row,
nuclear@2:             png_pass_mask[png_ptr->pass]);
nuclear@2:    }
nuclear@2:    else
nuclear@2: #endif
nuclear@2:    {
nuclear@2:       if (row != NULL)
nuclear@2:          png_combine_row(png_ptr, row, 0xff);
nuclear@2:       if (dsp_row != NULL)
nuclear@2:          png_combine_row(png_ptr, dsp_row, 0xff);
nuclear@2:    }
nuclear@2:    png_read_finish_row(png_ptr);
nuclear@2: 
nuclear@2:    if (png_ptr->read_row_fn != NULL)
nuclear@2:       (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: /* Read one or more rows of image data.  If the image is interlaced,
nuclear@2:  * and png_set_interlace_handling() has been called, the rows need to
nuclear@2:  * contain the contents of the rows from the previous pass.  If the
nuclear@2:  * image has alpha or transparency, and png_handle_alpha()[*] has been
nuclear@2:  * called, the rows contents must be initialized to the contents of the
nuclear@2:  * screen.
nuclear@2:  *
nuclear@2:  * "row" holds the actual image, and pixels are placed in it
nuclear@2:  * as they arrive.  If the image is displayed after each pass, it will
nuclear@2:  * appear to "sparkle" in.  "display_row" can be used to display a
nuclear@2:  * "chunky" progressive image, with finer detail added as it becomes
nuclear@2:  * available.  If you do not want this "chunky" display, you may pass
nuclear@2:  * NULL for display_row.  If you do not want the sparkle display, and
nuclear@2:  * you have not called png_handle_alpha(), you may pass NULL for rows.
nuclear@2:  * If you have called png_handle_alpha(), and the image has either an
nuclear@2:  * alpha channel or a transparency chunk, you must provide a buffer for
nuclear@2:  * rows.  In this case, you do not have to provide a display_row buffer
nuclear@2:  * also, but you may.  If the image is not interlaced, or if you have
nuclear@2:  * not called png_set_interlace_handling(), the display_row buffer will
nuclear@2:  * be ignored, so pass NULL to it.
nuclear@2:  *
nuclear@2:  * [*] png_handle_alpha() does not exist yet, as of this version of libpng
nuclear@2:  */
nuclear@2: 
nuclear@2: void PNGAPI
nuclear@2: png_read_rows(png_structp png_ptr, png_bytepp row,
nuclear@2:    png_bytepp display_row, png_uint_32 num_rows)
nuclear@2: {
nuclear@2:    png_uint_32 i;
nuclear@2:    png_bytepp rp;
nuclear@2:    png_bytepp dp;
nuclear@2: 
nuclear@2:    png_debug(1, "in png_read_rows\n");
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    rp = row;
nuclear@2:    dp = display_row;
nuclear@2:    if (rp != NULL && dp != NULL)
nuclear@2:       for (i = 0; i < num_rows; i++)
nuclear@2:       {
nuclear@2:          png_bytep rptr = *rp++;
nuclear@2:          png_bytep dptr = *dp++;
nuclear@2: 
nuclear@2:          png_read_row(png_ptr, rptr, dptr);
nuclear@2:       }
nuclear@2:    else if (rp != NULL)
nuclear@2:       for (i = 0; i < num_rows; i++)
nuclear@2:       {
nuclear@2:          png_bytep rptr = *rp;
nuclear@2:          png_read_row(png_ptr, rptr, png_bytep_NULL);
nuclear@2:          rp++;
nuclear@2:       }
nuclear@2:    else if (dp != NULL)
nuclear@2:       for (i = 0; i < num_rows; i++)
nuclear@2:       {
nuclear@2:          png_bytep dptr = *dp;
nuclear@2:          png_read_row(png_ptr, png_bytep_NULL, dptr);
nuclear@2:          dp++;
nuclear@2:       }
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: /* Read the entire image.  If the image has an alpha channel or a tRNS
nuclear@2:  * chunk, and you have called png_handle_alpha()[*], you will need to
nuclear@2:  * initialize the image to the current image that PNG will be overlaying.
nuclear@2:  * We set the num_rows again here, in case it was incorrectly set in
nuclear@2:  * png_read_start_row() by a call to png_read_update_info() or
nuclear@2:  * png_start_read_image() if png_set_interlace_handling() wasn't called
nuclear@2:  * prior to either of these functions like it should have been.  You can
nuclear@2:  * only call this function once.  If you desire to have an image for
nuclear@2:  * each pass of a interlaced image, use png_read_rows() instead.
nuclear@2:  *
nuclear@2:  * [*] png_handle_alpha() does not exist yet, as of this version of libpng
nuclear@2:  */
nuclear@2: void PNGAPI
nuclear@2: png_read_image(png_structp png_ptr, png_bytepp image)
nuclear@2: {
nuclear@2:    png_uint_32 i, image_height;
nuclear@2:    int pass, j;
nuclear@2:    png_bytepp rp;
nuclear@2: 
nuclear@2:    png_debug(1, "in png_read_image\n");
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2: 
nuclear@2: #ifdef PNG_READ_INTERLACING_SUPPORTED
nuclear@2:    pass = png_set_interlace_handling(png_ptr);
nuclear@2: #else
nuclear@2:    if (png_ptr->interlaced)
nuclear@2:       png_error(png_ptr,
nuclear@2:         "Cannot read interlaced image -- interlace handler disabled.");
nuclear@2:    pass = 1;
nuclear@2: #endif
nuclear@2: 
nuclear@2: 
nuclear@2:    image_height=png_ptr->height;
nuclear@2:    png_ptr->num_rows = image_height; /* Make sure this is set correctly */
nuclear@2: 
nuclear@2:    for (j = 0; j < pass; j++)
nuclear@2:    {
nuclear@2:       rp = image;
nuclear@2:       for (i = 0; i < image_height; i++)
nuclear@2:       {
nuclear@2:          png_read_row(png_ptr, *rp, png_bytep_NULL);
nuclear@2:          rp++;
nuclear@2:       }
nuclear@2:    }
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: /* Read the end of the PNG file.  Will not read past the end of the
nuclear@2:  * file, will verify the end is accurate, and will read any comments
nuclear@2:  * or time information at the end of the file, if info is not NULL.
nuclear@2:  */
nuclear@2: void PNGAPI
nuclear@2: png_read_end(png_structp png_ptr, png_infop info_ptr)
nuclear@2: {
nuclear@2:    png_debug(1, "in png_read_end\n");
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
nuclear@2: 
nuclear@2:    do
nuclear@2:    {
nuclear@2: #ifdef PNG_USE_LOCAL_ARRAYS
nuclear@2:       PNG_CONST PNG_IHDR;
nuclear@2:       PNG_CONST PNG_IDAT;
nuclear@2:       PNG_CONST PNG_IEND;
nuclear@2:       PNG_CONST PNG_PLTE;
nuclear@2: #if defined(PNG_READ_bKGD_SUPPORTED)
nuclear@2:       PNG_CONST PNG_bKGD;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_cHRM_SUPPORTED)
nuclear@2:       PNG_CONST PNG_cHRM;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_gAMA_SUPPORTED)
nuclear@2:       PNG_CONST PNG_gAMA;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_hIST_SUPPORTED)
nuclear@2:       PNG_CONST PNG_hIST;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iCCP_SUPPORTED)
nuclear@2:       PNG_CONST PNG_iCCP;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iTXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_iTXt;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_oFFs_SUPPORTED)
nuclear@2:       PNG_CONST PNG_oFFs;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pCAL_SUPPORTED)
nuclear@2:       PNG_CONST PNG_pCAL;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pHYs_SUPPORTED)
nuclear@2:       PNG_CONST PNG_pHYs;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sBIT_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sBIT;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sCAL_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sCAL;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sPLT_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sPLT;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sRGB_SUPPORTED)
nuclear@2:       PNG_CONST PNG_sRGB;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tEXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tEXt;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tIME_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tIME;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tRNS_SUPPORTED)
nuclear@2:       PNG_CONST PNG_tRNS;
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_zTXt_SUPPORTED)
nuclear@2:       PNG_CONST PNG_zTXt;
nuclear@2: #endif
nuclear@2: #endif /* PNG_USE_LOCAL_ARRAYS */
nuclear@2:       png_uint_32 length = png_read_chunk_header(png_ptr);
nuclear@2:       PNG_CONST png_bytep chunk_name = png_ptr->chunk_name;
nuclear@2: 
nuclear@2:       if (!png_memcmp(chunk_name, png_IHDR, 4))
nuclear@2:          png_handle_IHDR(png_ptr, info_ptr, length);
nuclear@2:       else if (!png_memcmp(chunk_name, png_IEND, 4))
nuclear@2:          png_handle_IEND(png_ptr, info_ptr, length);
nuclear@2: #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
nuclear@2:       else if (png_handle_as_unknown(png_ptr, chunk_name))
nuclear@2:       {
nuclear@2:          if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:          {
nuclear@2:             if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
nuclear@2:                png_error(png_ptr, "Too many IDAT's found");
nuclear@2:          }
nuclear@2:          png_handle_unknown(png_ptr, info_ptr, length);
nuclear@2:          if (!png_memcmp(chunk_name, png_PLTE, 4))
nuclear@2:             png_ptr->mode |= PNG_HAVE_PLTE;
nuclear@2:       }
nuclear@2: #endif
nuclear@2:       else if (!png_memcmp(chunk_name, png_IDAT, 4))
nuclear@2:       {
nuclear@2:          /* Zero length IDATs are legal after the last IDAT has been
nuclear@2:           * read, but not after other chunks have been read.
nuclear@2:           */
nuclear@2:          if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
nuclear@2:             png_error(png_ptr, "Too many IDAT's found");
nuclear@2:          png_crc_finish(png_ptr, length);
nuclear@2:       }
nuclear@2:       else if (!png_memcmp(chunk_name, png_PLTE, 4))
nuclear@2:          png_handle_PLTE(png_ptr, info_ptr, length);
nuclear@2: #if defined(PNG_READ_bKGD_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_bKGD, 4))
nuclear@2:          png_handle_bKGD(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_cHRM_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_cHRM, 4))
nuclear@2:          png_handle_cHRM(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_gAMA_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_gAMA, 4))
nuclear@2:          png_handle_gAMA(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_hIST_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_hIST, 4))
nuclear@2:          png_handle_hIST(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_oFFs_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_oFFs, 4))
nuclear@2:          png_handle_oFFs(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pCAL_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_pCAL, 4))
nuclear@2:          png_handle_pCAL(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sCAL_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sCAL, 4))
nuclear@2:          png_handle_sCAL(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_pHYs_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_pHYs, 4))
nuclear@2:          png_handle_pHYs(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sBIT_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sBIT, 4))
nuclear@2:          png_handle_sBIT(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sRGB_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sRGB, 4))
nuclear@2:          png_handle_sRGB(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iCCP_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_iCCP, 4))
nuclear@2:          png_handle_iCCP(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_sPLT_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_sPLT, 4))
nuclear@2:          png_handle_sPLT(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tEXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tEXt, 4))
nuclear@2:          png_handle_tEXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tIME_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tIME, 4))
nuclear@2:          png_handle_tIME(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_tRNS_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_tRNS, 4))
nuclear@2:          png_handle_tRNS(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_zTXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_zTXt, 4))
nuclear@2:          png_handle_zTXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_iTXt_SUPPORTED)
nuclear@2:       else if (!png_memcmp(chunk_name, png_iTXt, 4))
nuclear@2:          png_handle_iTXt(png_ptr, info_ptr, length);
nuclear@2: #endif
nuclear@2:       else
nuclear@2:          png_handle_unknown(png_ptr, info_ptr, length);
nuclear@2:    } while (!(png_ptr->mode & PNG_HAVE_IEND));
nuclear@2: }
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: 
nuclear@2: /* free all memory used by the read */
nuclear@2: void PNGAPI
nuclear@2: png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
nuclear@2:    png_infopp end_info_ptr_ptr)
nuclear@2: {
nuclear@2:    png_structp png_ptr = NULL;
nuclear@2:    png_infop info_ptr = NULL, end_info_ptr = NULL;
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    png_free_ptr free_fn = NULL;
nuclear@2:    png_voidp mem_ptr = NULL;
nuclear@2: #endif
nuclear@2: 
nuclear@2:    png_debug(1, "in png_destroy_read_struct\n");
nuclear@2:    if (png_ptr_ptr != NULL)
nuclear@2:       png_ptr = *png_ptr_ptr;
nuclear@2:    if (png_ptr == NULL)
nuclear@2:       return;
nuclear@2: 
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    free_fn = png_ptr->free_fn;
nuclear@2:    mem_ptr = png_ptr->mem_ptr;
nuclear@2: #endif
nuclear@2: 
nuclear@2:    if (info_ptr_ptr != NULL)
nuclear@2:       info_ptr = *info_ptr_ptr;
nuclear@2: 
nuclear@2:    if (end_info_ptr_ptr != NULL)
nuclear@2:       end_info_ptr = *end_info_ptr_ptr;
nuclear@2: 
nuclear@2:    png_read_destroy(png_ptr, info_ptr, end_info_ptr);
nuclear@2: 
nuclear@2:    if (info_ptr != NULL)
nuclear@2:    {
nuclear@2: #if defined(PNG_TEXT_SUPPORTED)
nuclear@2:       png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:       png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
nuclear@2:           (png_voidp)mem_ptr);
nuclear@2: #else
nuclear@2:       png_destroy_struct((png_voidp)info_ptr);
nuclear@2: #endif
nuclear@2:       *info_ptr_ptr = NULL;
nuclear@2:    }
nuclear@2: 
nuclear@2:    if (end_info_ptr != NULL)
nuclear@2:    {
nuclear@2: #if defined(PNG_READ_TEXT_SUPPORTED)
nuclear@2:       png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1);
nuclear@2: #endif
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:       png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn,
nuclear@2:          (png_voidp)mem_ptr);
nuclear@2: #else
nuclear@2:       png_destroy_struct((png_voidp)end_info_ptr);
nuclear@2: #endif
nuclear@2:       *end_info_ptr_ptr = NULL;
nuclear@2:    }
nuclear@2: 
nuclear@2:    if (png_ptr != NULL)
nuclear@2:    {
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:       png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
nuclear@2:           (png_voidp)mem_ptr);
nuclear@2: #else
nuclear@2:       png_destroy_struct((png_voidp)png_ptr);
nuclear@2: #endif
nuclear@2:       *png_ptr_ptr = NULL;
nuclear@2:    }
nuclear@2: }
nuclear@2: 
nuclear@2: /* free all memory used by the read (old method) */
nuclear@2: void /* PRIVATE */
nuclear@2: png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
nuclear@2: {
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    jmp_buf tmp_jmp;
nuclear@2: #endif
nuclear@2:    png_error_ptr error_fn;
nuclear@2:    png_error_ptr warning_fn;
nuclear@2:    png_voidp error_ptr;
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    png_free_ptr free_fn;
nuclear@2: #endif
nuclear@2: 
nuclear@2:    png_debug(1, "in png_read_destroy\n");
nuclear@2:    if (info_ptr != NULL)
nuclear@2:       png_info_destroy(png_ptr, info_ptr);
nuclear@2: 
nuclear@2:    if (end_info_ptr != NULL)
nuclear@2:       png_info_destroy(png_ptr, end_info_ptr);
nuclear@2: 
nuclear@2:    png_free(png_ptr, png_ptr->zbuf);
nuclear@2:    png_free(png_ptr, png_ptr->big_row_buf);
nuclear@2:    png_free(png_ptr, png_ptr->prev_row);
nuclear@2:    png_free(png_ptr, png_ptr->chunkdata);
nuclear@2: #if defined(PNG_READ_DITHER_SUPPORTED)
nuclear@2:    png_free(png_ptr, png_ptr->palette_lookup);
nuclear@2:    png_free(png_ptr, png_ptr->dither_index);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_GAMMA_SUPPORTED)
nuclear@2:    png_free(png_ptr, png_ptr->gamma_table);
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_BACKGROUND_SUPPORTED)
nuclear@2:    png_free(png_ptr, png_ptr->gamma_from_1);
nuclear@2:    png_free(png_ptr, png_ptr->gamma_to_1);
nuclear@2: #endif
nuclear@2: #ifdef PNG_FREE_ME_SUPPORTED
nuclear@2:    if (png_ptr->free_me & PNG_FREE_PLTE)
nuclear@2:       png_zfree(png_ptr, png_ptr->palette);
nuclear@2:    png_ptr->free_me &= ~PNG_FREE_PLTE;
nuclear@2: #else
nuclear@2:    if (png_ptr->flags & PNG_FLAG_FREE_PLTE)
nuclear@2:       png_zfree(png_ptr, png_ptr->palette);
nuclear@2:    png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
nuclear@2: #endif
nuclear@2: #if defined(PNG_tRNS_SUPPORTED) || \
nuclear@2:     defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
nuclear@2: #ifdef PNG_FREE_ME_SUPPORTED
nuclear@2:    if (png_ptr->free_me & PNG_FREE_TRNS)
nuclear@2:       png_free(png_ptr, png_ptr->trans);
nuclear@2:    png_ptr->free_me &= ~PNG_FREE_TRNS;
nuclear@2: #else
nuclear@2:    if (png_ptr->flags & PNG_FLAG_FREE_TRNS)
nuclear@2:       png_free(png_ptr, png_ptr->trans);
nuclear@2:    png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
nuclear@2: #endif
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_hIST_SUPPORTED)
nuclear@2: #ifdef PNG_FREE_ME_SUPPORTED
nuclear@2:    if (png_ptr->free_me & PNG_FREE_HIST)
nuclear@2:       png_free(png_ptr, png_ptr->hist);
nuclear@2:    png_ptr->free_me &= ~PNG_FREE_HIST;
nuclear@2: #else
nuclear@2:    if (png_ptr->flags & PNG_FLAG_FREE_HIST)
nuclear@2:       png_free(png_ptr, png_ptr->hist);
nuclear@2:    png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
nuclear@2: #endif
nuclear@2: #endif
nuclear@2: #if defined(PNG_READ_GAMMA_SUPPORTED)
nuclear@2:    if (png_ptr->gamma_16_table != NULL)
nuclear@2:    {
nuclear@2:       int i;
nuclear@2:       int istop = (1 << (8 - png_ptr->gamma_shift));
nuclear@2:       for (i = 0; i < istop; i++)
nuclear@2:       {
nuclear@2:          png_free(png_ptr, png_ptr->gamma_16_table[i]);
nuclear@2:       }
nuclear@2:    png_free(png_ptr, png_ptr->gamma_16_table);
nuclear@2:    }
nuclear@2: #if defined(PNG_READ_BACKGROUND_SUPPORTED)
nuclear@2:    if (png_ptr->gamma_16_from_1 != NULL)
nuclear@2:    {
nuclear@2:       int i;
nuclear@2:       int istop = (1 << (8 - png_ptr->gamma_shift));
nuclear@2:       for (i = 0; i < istop; i++)
nuclear@2:       {
nuclear@2:          png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
nuclear@2:       }
nuclear@2:    png_free(png_ptr, png_ptr->gamma_16_from_1);
nuclear@2:    }
nuclear@2:    if (png_ptr->gamma_16_to_1 != NULL)
nuclear@2:    {
nuclear@2:       int i;
nuclear@2:       int istop = (1 << (8 - png_ptr->gamma_shift));
nuclear@2:       for (i = 0; i < istop; i++)
nuclear@2:       {
nuclear@2:          png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
nuclear@2:       }
nuclear@2:    png_free(png_ptr, png_ptr->gamma_16_to_1);
nuclear@2:    }
nuclear@2: #endif
nuclear@2: #endif
nuclear@2: #if defined(PNG_TIME_RFC1123_SUPPORTED)
nuclear@2:    png_free(png_ptr, png_ptr->time_buffer);
nuclear@2: #endif
nuclear@2: 
nuclear@2:    inflateEnd(&png_ptr->zstream);
nuclear@2: #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
nuclear@2:    png_free(png_ptr, png_ptr->save_buffer);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
nuclear@2: #ifdef PNG_TEXT_SUPPORTED
nuclear@2:    png_free(png_ptr, png_ptr->current_text);
nuclear@2: #endif /* PNG_TEXT_SUPPORTED */
nuclear@2: #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
nuclear@2: 
nuclear@2:    /* Save the important info out of the png_struct, in case it is
nuclear@2:     * being used again.
nuclear@2:     */
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf));
nuclear@2: #endif
nuclear@2: 
nuclear@2:    error_fn = png_ptr->error_fn;
nuclear@2:    warning_fn = png_ptr->warning_fn;
nuclear@2:    error_ptr = png_ptr->error_ptr;
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    free_fn = png_ptr->free_fn;
nuclear@2: #endif
nuclear@2: 
nuclear@2:    png_memset(png_ptr, 0, png_sizeof(png_struct));
nuclear@2: 
nuclear@2:    png_ptr->error_fn = error_fn;
nuclear@2:    png_ptr->warning_fn = warning_fn;
nuclear@2:    png_ptr->error_ptr = error_ptr;
nuclear@2: #ifdef PNG_USER_MEM_SUPPORTED
nuclear@2:    png_ptr->free_fn = free_fn;
nuclear@2: #endif
nuclear@2: 
nuclear@2: #ifdef PNG_SETJMP_SUPPORTED
nuclear@2:    png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf));
nuclear@2: #endif
nuclear@2: 
nuclear@2: }
nuclear@2: 
nuclear@2: void PNGAPI
nuclear@2: png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
nuclear@2: {
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2:    png_ptr->read_row_fn = read_row_fn;
nuclear@2: }
nuclear@2: 
nuclear@2: 
nuclear@2: #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
nuclear@2: #if defined(PNG_INFO_IMAGE_SUPPORTED)
nuclear@2: void PNGAPI
nuclear@2: png_read_png(png_structp png_ptr, png_infop info_ptr,
nuclear@2:                            int transforms,
nuclear@2:                            voidp params)
nuclear@2: {
nuclear@2:    int row;
nuclear@2: 
nuclear@2:    if (png_ptr == NULL) return;
nuclear@2: #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
nuclear@2:    /* invert the alpha channel from opacity to transparency
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
nuclear@2:        png_set_invert_alpha(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2:    /* png_read_info() gives us all of the information from the
nuclear@2:     * PNG file before the first IDAT (image data chunk).
nuclear@2:     */
nuclear@2:    png_read_info(png_ptr, info_ptr);
nuclear@2:    if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
nuclear@2:       png_error(png_ptr, "Image is too high to process with png_read_png()");
nuclear@2: 
nuclear@2:    /* -------------- image transformations start here ------------------- */
nuclear@2: 
nuclear@2: #if defined(PNG_READ_16_TO_8_SUPPORTED)
nuclear@2:    /* tell libpng to strip 16 bit/color files down to 8 bits per color
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_STRIP_16)
nuclear@2:        png_set_strip_16(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
nuclear@2:    /* Strip alpha bytes from the input data without combining with
nuclear@2:     * the background (not recommended).
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
nuclear@2:        png_set_strip_alpha(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
nuclear@2:    /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
nuclear@2:     * byte into separate bytes (useful for paletted and grayscale images).
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_PACKING)
nuclear@2:        png_set_packing(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_PACKSWAP_SUPPORTED)
nuclear@2:    /* Change the order of packed pixels to least significant bit first
nuclear@2:     * (not useful if you are using png_set_packing).
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_PACKSWAP)
nuclear@2:        png_set_packswap(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_EXPAND_SUPPORTED)
nuclear@2:    /* Expand paletted colors into true RGB triplets
nuclear@2:     * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
nuclear@2:     * Expand paletted or RGB images with transparency to full alpha
nuclear@2:     * channels so the data will be available as RGBA quartets.
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_EXPAND)
nuclear@2:        if ((png_ptr->bit_depth < 8) ||
nuclear@2:            (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
nuclear@2:            (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
nuclear@2:          png_set_expand(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2:    /* We don't handle background color or gamma transformation or dithering.
nuclear@2:     */
nuclear@2: 
nuclear@2: #if defined(PNG_READ_INVERT_SUPPORTED)
nuclear@2:    /* invert monochrome files to have 0 as white and 1 as black
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_INVERT_MONO)
nuclear@2:        png_set_invert_mono(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_SHIFT_SUPPORTED)
nuclear@2:    /* If you want to shift the pixel values from the range [0,255] or
nuclear@2:     * [0,65535] to the original [0,7] or [0,31], or whatever range the
nuclear@2:     * colors were originally in:
nuclear@2:     */
nuclear@2:    if ((transforms & PNG_TRANSFORM_SHIFT)
nuclear@2:        && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
nuclear@2:    {
nuclear@2:       png_color_8p sig_bit;
nuclear@2: 
nuclear@2:       png_get_sBIT(png_ptr, info_ptr, &sig_bit);
nuclear@2:       png_set_shift(png_ptr, sig_bit);
nuclear@2:    }
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_BGR_SUPPORTED)
nuclear@2:    /* flip the RGB pixels to BGR (or RGBA to BGRA)
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_BGR)
nuclear@2:        png_set_bgr(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
nuclear@2:    /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
nuclear@2:        png_set_swap_alpha(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2: #if defined(PNG_READ_SWAP_SUPPORTED)
nuclear@2:    /* swap bytes of 16 bit files to least significant byte first
nuclear@2:     */
nuclear@2:    if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
nuclear@2:        png_set_swap(png_ptr);
nuclear@2: #endif
nuclear@2: 
nuclear@2:    /* We don't handle adding filler bytes */
nuclear@2: 
nuclear@2:    /* Optional call to gamma correct and add the background to the palette
nuclear@2:     * and update info structure.  REQUIRED if you are expecting libpng to
nuclear@2:     * update the palette for you (i.e., you selected such a transform above).
nuclear@2:     */
nuclear@2:    png_read_update_info(png_ptr, info_ptr);
nuclear@2: 
nuclear@2:    /* -------------- image transformations end here ------------------- */
nuclear@2: 
nuclear@2: #ifdef PNG_FREE_ME_SUPPORTED
nuclear@2:    png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
nuclear@2: #endif
nuclear@2:    if (info_ptr->row_pointers == NULL)
nuclear@2:    {
nuclear@2:       info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
nuclear@2:          info_ptr->height * png_sizeof(png_bytep));
nuclear@2: #ifdef PNG_FREE_ME_SUPPORTED
nuclear@2:       info_ptr->free_me |= PNG_FREE_ROWS;
nuclear@2: #endif
nuclear@2:       for (row = 0; row < (int)info_ptr->height; row++)
nuclear@2:       {
nuclear@2:          info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
nuclear@2:             png_get_rowbytes(png_ptr, info_ptr));
nuclear@2:       }
nuclear@2:    }
nuclear@2: 
nuclear@2:    png_read_image(png_ptr, info_ptr->row_pointers);
nuclear@2:    info_ptr->valid |= PNG_INFO_IDAT;
nuclear@2: 
nuclear@2:    /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
nuclear@2:    png_read_end(png_ptr, info_ptr);
nuclear@2: 
nuclear@2:    transforms = transforms; /* quiet compiler warnings */
nuclear@2:    params = params;
nuclear@2: 
nuclear@2: }
nuclear@2: #endif /* PNG_INFO_IMAGE_SUPPORTED */
nuclear@2: #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
nuclear@2: #endif /* PNG_READ_SUPPORTED */