The Tor Browser: media/libpng/pngset.c@97036ab72558 (annotated)

media/libpng/pngset.c@97036ab72558 (annotated)

media/libpng/pngset.c

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* pngset.c - storage of image information into info struct
  *
  * Last changed in libpng 1.6.8 [December 19, 2013]
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  *
  * The functions here are used during reads to store data from the file
  * into the info struct, and during writes to store application data
  * into the info struct for writing into the file.  This abstracts the
  * info struct and allows us to change the structure in the future.
  */
 #include "pngpriv.h"
 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
 #ifdef PNG_bKGD_SUPPORTED
 void PNGAPI
 png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_color_16p background)
 {
    png_debug1(1, "in %s storage function", "bKGD");
    if (png_ptr == NULL || info_ptr == NULL || background == NULL)
       return;
    info_ptr->background = *background;
    info_ptr->valid |= PNG_INFO_bKGD;
 }
 #endif
 #ifdef PNG_cHRM_SUPPORTED
 void PNGFAPI
 png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
     png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
     png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
     png_fixed_point blue_x, png_fixed_point blue_y)
 {
    png_xy xy;
    png_debug1(1, "in %s storage function", "cHRM fixed");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    xy.redx = red_x;
    xy.redy = red_y;
    xy.greenx = green_x;
    xy.greeny = green_y;
    xy.bluex = blue_x;
    xy.bluey = blue_y;
    xy.whitex = white_x;
    xy.whitey = white_y;
    if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
 /* override with app values*/))
       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
    png_colorspace_sync_info(png_ptr, info_ptr);
 }
 void PNGFAPI
 png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
     png_fixed_point int_red_X, png_fixed_point int_red_Y,
     png_fixed_point int_red_Z, png_fixed_point int_green_X,
     png_fixed_point int_green_Y, png_fixed_point int_green_Z,
     png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
     png_fixed_point int_blue_Z)
 {
    png_XYZ XYZ;
    png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    XYZ.red_X = int_red_X;
    XYZ.red_Y = int_red_Y;
    XYZ.red_Z = int_red_Z;
    XYZ.green_X = int_green_X;
    XYZ.green_Y = int_green_Y;
    XYZ.green_Z = int_green_Z;
    XYZ.blue_X = int_blue_X;
    XYZ.blue_Y = int_blue_Y;
    XYZ.blue_Z = int_blue_Z;
    if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2))
       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
    png_colorspace_sync_info(png_ptr, info_ptr);
 }
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 void PNGAPI
 png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
     double white_x, double white_y, double red_x, double red_y,
     double green_x, double green_y, double blue_x, double blue_y)
 {
    png_set_cHRM_fixed(png_ptr, info_ptr,
       png_fixed(png_ptr, white_x, "cHRM White X"),
       png_fixed(png_ptr, white_y, "cHRM White Y"),
       png_fixed(png_ptr, red_x, "cHRM Red X"),
       png_fixed(png_ptr, red_y, "cHRM Red Y"),
       png_fixed(png_ptr, green_x, "cHRM Green X"),
       png_fixed(png_ptr, green_y, "cHRM Green Y"),
       png_fixed(png_ptr, blue_x, "cHRM Blue X"),
       png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
 }
 void PNGAPI
 png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
     double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
     double blue_X, double blue_Y, double blue_Z)
 {
    png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
       png_fixed(png_ptr, red_X, "cHRM Red X"),
       png_fixed(png_ptr, red_Y, "cHRM Red Y"),
       png_fixed(png_ptr, red_Z, "cHRM Red Z"),
       png_fixed(png_ptr, green_X, "cHRM Red X"),
       png_fixed(png_ptr, green_Y, "cHRM Red Y"),
       png_fixed(png_ptr, green_Z, "cHRM Red Z"),
       png_fixed(png_ptr, blue_X, "cHRM Red X"),
       png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
       png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
 }
 #  endif /* PNG_FLOATING_POINT_SUPPORTED */
 #endif /* PNG_cHRM_SUPPORTED */
 #ifdef PNG_gAMA_SUPPORTED
 void PNGFAPI
 png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
     png_fixed_point file_gamma)
 {
    png_debug1(1, "in %s storage function", "gAMA");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma);
    png_colorspace_sync_info(png_ptr, info_ptr);
 }
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 void PNGAPI
 png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma)
 {
    png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
        "png_set_gAMA"));
 }
 #  endif
 #endif
 #ifdef PNG_hIST_SUPPORTED
 void PNGAPI
 png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_uint_16p hist)
 {
    int i;
    png_debug1(1, "in %s storage function", "hIST");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    if (info_ptr->num_palette == 0 || info_ptr->num_palette
        > PNG_MAX_PALETTE_LENGTH)
    {
       png_warning(png_ptr,
           "Invalid palette size, hIST allocation skipped");
       return;
    }
    png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
    /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
     * version 1.2.1
     */
    info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr,
        PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16))));
    if (info_ptr->hist == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for hIST chunk data");
       return;
    }
    info_ptr->free_me |= PNG_FREE_HIST;
    for (i = 0; i < info_ptr->num_palette; i++)
       info_ptr->hist[i] = hist[i];
    info_ptr->valid |= PNG_INFO_hIST;
 }
 #endif
 void PNGAPI
 png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
     png_uint_32 width, png_uint_32 height, int bit_depth,
     int color_type, int interlace_type, int compression_type,
     int filter_type)
 {
    png_debug1(1, "in %s storage function", "IHDR");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    info_ptr->width = width;
    info_ptr->height = height;
    info_ptr->bit_depth = (png_byte)bit_depth;
    info_ptr->color_type = (png_byte)color_type;
    info_ptr->compression_type = (png_byte)compression_type;
    info_ptr->filter_type = (png_byte)filter_type;
    info_ptr->interlace_type = (png_byte)interlace_type;
    png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
        info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
        info_ptr->compression_type, info_ptr->filter_type);
    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       info_ptr->channels = 1;
    else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
       info_ptr->channels = 3;
    else
       info_ptr->channels = 1;
    if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
       info_ptr->channels++;
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
    info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
 #ifdef PNG_APNG_SUPPORTED
    /* for non-animated png. this may be overwritten from an acTL chunk later */
    info_ptr->num_frames = 1;
 #endif
 }
 #ifdef PNG_oFFs_SUPPORTED
 void PNGAPI
 png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr,
     png_int_32 offset_x, png_int_32 offset_y, int unit_type)
 {
    png_debug1(1, "in %s storage function", "oFFs");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    info_ptr->x_offset = offset_x;
    info_ptr->y_offset = offset_y;
    info_ptr->offset_unit_type = (png_byte)unit_type;
    info_ptr->valid |= PNG_INFO_oFFs;
 }
 #endif
 #ifdef PNG_pCAL_SUPPORTED
 void PNGAPI
 png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
     int nparams, png_const_charp units, png_charpp params)
 {
    png_size_t length;
    int i;
    png_debug1(1, "in %s storage function", "pCAL");
    if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
       || (nparams > 0 && params == NULL))
       return;
    length = strlen(purpose) + 1;
    png_debug1(3, "allocating purpose for info (%lu bytes)",
        (unsigned long)length);
    /* TODO: validate format of calibration name and unit name */
    /* Check that the type matches the specification. */
    if (type < 0 || type > 3)
       png_error(png_ptr, "Invalid pCAL equation type");
    if (nparams < 0 || nparams > 255)
       png_error(png_ptr, "Invalid pCAL parameter count");
    /* Validate params[nparams] */
    for (i=0; i<nparams; ++i)
       if (params[i] == NULL ||
          !png_check_fp_string(params[i], strlen(params[i])))
          png_error(png_ptr, "Invalid format for pCAL parameter");
    info_ptr->pcal_purpose = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, length));
    if (info_ptr->pcal_purpose == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for pCAL purpose");
       return;
    }
    memcpy(info_ptr->pcal_purpose, purpose, length);
    png_debug(3, "storing X0, X1, type, and nparams in info");
    info_ptr->pcal_X0 = X0;
    info_ptr->pcal_X1 = X1;
    info_ptr->pcal_type = (png_byte)type;
    info_ptr->pcal_nparams = (png_byte)nparams;
    length = strlen(units) + 1;
    png_debug1(3, "allocating units for info (%lu bytes)",
      (unsigned long)length);
    info_ptr->pcal_units = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, length));
    if (info_ptr->pcal_units == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for pCAL units");
       return;
    }
    memcpy(info_ptr->pcal_units, units, length);
    info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
        (png_size_t)((nparams + 1) * (sizeof (png_charp)))));
    if (info_ptr->pcal_params == NULL)
    {
       png_warning(png_ptr, "Insufficient memory for pCAL params");
       return;
    }
    memset(info_ptr->pcal_params, 0, (nparams + 1) * (sizeof (png_charp)));
    for (i = 0; i < nparams; i++)
    {
       length = strlen(params[i]) + 1;
       png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
           (unsigned long)length);
       info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
       if (info_ptr->pcal_params[i] == NULL)
       {
          png_warning(png_ptr, "Insufficient memory for pCAL parameter");
          return;
       }
       memcpy(info_ptr->pcal_params[i], params[i], length);
    }
    info_ptr->valid |= PNG_INFO_pCAL;
    info_ptr->free_me |= PNG_FREE_PCAL;
 }
 #endif
 #ifdef PNG_sCAL_SUPPORTED
 void PNGAPI
 png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
     int unit, png_const_charp swidth, png_const_charp sheight)
 {
    png_size_t lengthw = 0, lengthh = 0;
    png_debug1(1, "in %s storage function", "sCAL");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    /* Double check the unit (should never get here with an invalid
     * unit unless this is an API call.)
     */
    if (unit != 1 && unit != 2)
       png_error(png_ptr, "Invalid sCAL unit");
    if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
        swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
       png_error(png_ptr, "Invalid sCAL width");
    if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
        sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
       png_error(png_ptr, "Invalid sCAL height");
    info_ptr->scal_unit = (png_byte)unit;
    ++lengthw;
    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
    info_ptr->scal_s_width = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, lengthw));
    if (info_ptr->scal_s_width == NULL)
    {
       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
       return;
    }
    memcpy(info_ptr->scal_s_width, swidth, lengthw);
    ++lengthh;
    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
    info_ptr->scal_s_height = png_voidcast(png_charp,
       png_malloc_warn(png_ptr, lengthh));
    if (info_ptr->scal_s_height == NULL)
    {
       png_free (png_ptr, info_ptr->scal_s_width);
       info_ptr->scal_s_width = NULL;
       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
       return;
    }
    memcpy(info_ptr->scal_s_height, sheight, lengthh);
    info_ptr->valid |= PNG_INFO_sCAL;
    info_ptr->free_me |= PNG_FREE_SCAL;
 }
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 void PNGAPI
 png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
     double width, double height)
 {
    png_debug1(1, "in %s storage function", "sCAL");
    /* Check the arguments. */
    if (width <= 0)
       png_warning(png_ptr, "Invalid sCAL width ignored");
    else if (height <= 0)
       png_warning(png_ptr, "Invalid sCAL height ignored");
    else
    {
       /* Convert 'width' and 'height' to ASCII. */
       char swidth[PNG_sCAL_MAX_DIGITS+1];
       char sheight[PNG_sCAL_MAX_DIGITS+1];
       png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width,
          PNG_sCAL_PRECISION);
       png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height,
          PNG_sCAL_PRECISION);
       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
    }
 }
 #  endif
 #  ifdef PNG_FIXED_POINT_SUPPORTED
 void PNGAPI
 png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
     png_fixed_point width, png_fixed_point height)
 {
    png_debug1(1, "in %s storage function", "sCAL");
    /* Check the arguments. */
    if (width <= 0)
       png_warning(png_ptr, "Invalid sCAL width ignored");
    else if (height <= 0)
       png_warning(png_ptr, "Invalid sCAL height ignored");
    else
    {
       /* Convert 'width' and 'height' to ASCII. */
       char swidth[PNG_sCAL_MAX_DIGITS+1];
       char sheight[PNG_sCAL_MAX_DIGITS+1];
       png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width);
       png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height);
       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
    }
 }
 #  endif
 #endif
 #ifdef PNG_pHYs_SUPPORTED
 void PNGAPI
 png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr,
     png_uint_32 res_x, png_uint_32 res_y, int unit_type)
 {
    png_debug1(1, "in %s storage function", "pHYs");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    info_ptr->x_pixels_per_unit = res_x;
    info_ptr->y_pixels_per_unit = res_y;
    info_ptr->phys_unit_type = (png_byte)unit_type;
    info_ptr->valid |= PNG_INFO_pHYs;
 }
 #endif
 void PNGAPI
 png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
     png_const_colorp palette, int num_palette)
 {
    png_debug1(1, "in %s storage function", "PLTE");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
    {
       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
          png_error(png_ptr, "Invalid palette length");
       else
       {
          png_warning(png_ptr, "Invalid palette length");
          return;
       }
    }
    if ((num_palette > 0 && palette == NULL) ||
       (num_palette == 0
 #        ifdef PNG_MNG_FEATURES_SUPPORTED
             && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
 #        endif
       ))
    {
       png_error(png_ptr, "Invalid palette");
       return;
    }
    /* It may not actually be necessary to set png_ptr->palette here;
     * we do it for backward compatibility with the way the png_handle_tRNS
     * function used to do the allocation.
     *
     * 1.6.0: the above statement appears to be incorrect; something has to set
     * the palette inside png_struct on read.
     */
    png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
    /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
     * of num_palette entries, in case of an invalid PNG file that has
     * too-large sample values.
     */
    png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
        PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));
    if (num_palette > 0)
       memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
    info_ptr->palette = png_ptr->palette;
    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
    info_ptr->free_me |= PNG_FREE_PLTE;
    info_ptr->valid |= PNG_INFO_PLTE;
 }
 #ifdef PNG_sBIT_SUPPORTED
 void PNGAPI
 png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_color_8p sig_bit)
 {
    png_debug1(1, "in %s storage function", "sBIT");
    if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL)
       return;
    info_ptr->sig_bit = *sig_bit;
    info_ptr->valid |= PNG_INFO_sBIT;
 }
 #endif
 #ifdef PNG_sRGB_SUPPORTED
 void PNGAPI
 png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent)
 {
    png_debug1(1, "in %s storage function", "sRGB");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent);
    png_colorspace_sync_info(png_ptr, info_ptr);
 }
 void PNGAPI
 png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
     int srgb_intent)
 {
    png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent))
    {
       /* This causes the gAMA and cHRM to be written too */
       info_ptr->colorspace.flags |=
          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
    }
    png_colorspace_sync_info(png_ptr, info_ptr);
 }
 #endif /* sRGB */
 #ifdef PNG_iCCP_SUPPORTED
 void PNGAPI
 png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_charp name, int compression_type,
     png_const_bytep profile, png_uint_32 proflen)
 {
    png_charp new_iccp_name;
    png_bytep new_iccp_profile;
    png_size_t length;
    png_debug1(1, "in %s storage function", "iCCP");
    if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
       return;
    if (compression_type != PNG_COMPRESSION_TYPE_BASE)
       png_app_error(png_ptr, "Invalid iCCP compression method");
    /* Set the colorspace first because this validates the profile; do not
     * override previously set app cHRM or gAMA here (because likely as not the
     * application knows better than libpng what the correct values are.)  Pass
     * the info_ptr color_type field to png_colorspace_set_ICC because in the
     * write case it has not yet been stored in png_ptr.
     */
    {
       int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
          proflen, profile, info_ptr->color_type);
       png_colorspace_sync_info(png_ptr, info_ptr);
       /* Don't do any of the copying if the profile was bad, or inconsistent. */
       if (!result)
          return;
       /* But do write the gAMA and cHRM chunks from the profile. */
       info_ptr->colorspace.flags |=
          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
    }
    length = strlen(name)+1;
    new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));
    if (new_iccp_name == NULL)
    {
       png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
       return;
    }
    memcpy(new_iccp_name, name, length);
    new_iccp_profile = png_voidcast(png_bytep,
       png_malloc_warn(png_ptr, proflen));
    if (new_iccp_profile == NULL)
    {
       png_free(png_ptr, new_iccp_name);
       png_benign_error(png_ptr,
           "Insufficient memory to process iCCP profile");
       return;
    }
    memcpy(new_iccp_profile, profile, proflen);
    png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
    info_ptr->iccp_proflen = proflen;
    info_ptr->iccp_name = new_iccp_name;
    info_ptr->iccp_profile = new_iccp_profile;
    info_ptr->free_me |= PNG_FREE_ICCP;
    info_ptr->valid |= PNG_INFO_iCCP;
 }
 #endif
 #ifdef PNG_TEXT_SUPPORTED
 void PNGAPI
 png_set_text(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_textp text_ptr, int num_text)
 {
    int ret;
    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
    if (ret)
       png_error(png_ptr, "Insufficient memory to store text");
 }
 int /* PRIVATE */
 png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_textp text_ptr, int num_text)
 {
    int i;
    png_debug1(1, "in %lx storage function", png_ptr == NULL ? "unexpected" :
       (unsigned long)png_ptr->chunk_name);
    if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
       return(0);
    /* Make sure we have enough space in the "text" array in info_struct
     * to hold all of the incoming text_ptr objects.  This compare can't overflow
     * because max_text >= num_text (anyway, subtract of two positive integers
     * can't overflow in any case.)
     */
    if (num_text > info_ptr->max_text - info_ptr->num_text)
    {
       int old_num_text = info_ptr->num_text;
       int max_text;
       png_textp new_text = NULL;
       /* Calculate an appropriate max_text, checking for overflow. */
       max_text = old_num_text;
       if (num_text <= INT_MAX - max_text)
       {
          max_text += num_text;
          /* Round up to a multiple of 8 */
          if (max_text < INT_MAX-8)
             max_text = (max_text + 8) & ~0x7;
          else
             max_text = INT_MAX;
          /* Now allocate a new array and copy the old members in, this does all
           * the overflow checks.
           */
          new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
             info_ptr->text, old_num_text, max_text-old_num_text,
             sizeof *new_text));
       }
       if (new_text == NULL)
       {
          png_chunk_report(png_ptr, "too many text chunks",
             PNG_CHUNK_WRITE_ERROR);
          return 1;
       }
       png_free(png_ptr, info_ptr->text);
       info_ptr->text = new_text;
       info_ptr->free_me |= PNG_FREE_TEXT;
       info_ptr->max_text = max_text;
       /* num_text is adjusted below as the entries are copied in */
       png_debug1(3, "allocated %d entries for info_ptr->text", max_text);
    }
    for (i = 0; i < num_text; i++)
    {
       size_t text_length, key_len;
       size_t lang_len, lang_key_len;
       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
       if (text_ptr[i].key == NULL)
           continue;
       if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
           text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
       {
          png_chunk_report(png_ptr, "text compression mode is out of range",
             PNG_CHUNK_WRITE_ERROR);
          continue;
       }
       key_len = strlen(text_ptr[i].key);
       if (text_ptr[i].compression <= 0)
       {
          lang_len = 0;
          lang_key_len = 0;
       }
       else
 #  ifdef PNG_iTXt_SUPPORTED
       {
          /* Set iTXt data */
          if (text_ptr[i].lang != NULL)
             lang_len = strlen(text_ptr[i].lang);
          else
             lang_len = 0;
          if (text_ptr[i].lang_key != NULL)
             lang_key_len = strlen(text_ptr[i].lang_key);
          else
             lang_key_len = 0;
       }
 #  else /* PNG_iTXt_SUPPORTED */
       {
          png_chunk_report(png_ptr, "iTXt chunk not supported",
             PNG_CHUNK_WRITE_ERROR);
          continue;
       }
 #  endif
       if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
       {
          text_length = 0;
 #  ifdef PNG_iTXt_SUPPORTED
          if (text_ptr[i].compression > 0)
             textp->compression = PNG_ITXT_COMPRESSION_NONE;
          else
 #  endif
             textp->compression = PNG_TEXT_COMPRESSION_NONE;
       }
       else
       {
          text_length = strlen(text_ptr[i].text);
          textp->compression = text_ptr[i].compression;
       }
       textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr,
           key_len + text_length + lang_len + lang_key_len + 4));
       if (textp->key == NULL)
       {
          png_chunk_report(png_ptr, "text chunk: out of memory",
                PNG_CHUNK_WRITE_ERROR);
          return 1;
       }
       png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
           (unsigned long)(png_uint_32)
           (key_len + lang_len + lang_key_len + text_length + 4),
           textp->key);
       memcpy(textp->key, text_ptr[i].key, key_len);
       *(textp->key + key_len) = '\0';
       if (text_ptr[i].compression > 0)
       {
          textp->lang = textp->key + key_len + 1;
          memcpy(textp->lang, text_ptr[i].lang, lang_len);
          *(textp->lang + lang_len) = '\0';
          textp->lang_key = textp->lang + lang_len + 1;
          memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
          *(textp->lang_key + lang_key_len) = '\0';
          textp->text = textp->lang_key + lang_key_len + 1;
       }
       else
       {
          textp->lang=NULL;
          textp->lang_key=NULL;
          textp->text = textp->key + key_len + 1;
       }
       if (text_length)
          memcpy(textp->text, text_ptr[i].text, text_length);
       *(textp->text + text_length) = '\0';
 #  ifdef PNG_iTXt_SUPPORTED
       if (textp->compression > 0)
       {
          textp->text_length = 0;
          textp->itxt_length = text_length;
       }
       else
 #  endif
       {
          textp->text_length = text_length;
          textp->itxt_length = 0;
       }
       info_ptr->num_text++;
       png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
    }
    return(0);
 }
 #endif
 #ifdef PNG_tIME_SUPPORTED
 void PNGAPI
 png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
     png_const_timep mod_time)
 {
    png_debug1(1, "in %s storage function", "tIME");
    if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
        (png_ptr->mode & PNG_WROTE_tIME))
       return;
    if (mod_time->month == 0   || mod_time->month > 12  ||
        mod_time->day   == 0   || mod_time->day   > 31  ||
        mod_time->hour  > 23   || mod_time->minute > 59 ||
        mod_time->second > 60)
    {
       png_warning(png_ptr, "Ignoring invalid time value");
       return;
    }
    info_ptr->mod_time = *mod_time;
    info_ptr->valid |= PNG_INFO_tIME;
 }
 #endif
 #ifdef PNG_tRNS_SUPPORTED
 void PNGAPI
 png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
     png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
 {
    png_debug1(1, "in %s storage function", "tRNS");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    if (trans_alpha != NULL)
    {
        /* It may not actually be necessary to set png_ptr->trans_alpha here;
         * we do it for backward compatibility with the way the png_handle_tRNS
         * function used to do the allocation.
         *
         * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
         * relies on png_set_tRNS storing the information in png_struct
         * (otherwise it won't be there for the code in pngrtran.c).
         */
        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
        /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
        png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
          png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
        if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
           memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
    }
    if (trans_color != NULL)
    {
       int sample_max = (1 << info_ptr->bit_depth);
       if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
           trans_color->gray > sample_max) ||
           (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
           (trans_color->red > sample_max ||
           trans_color->green > sample_max ||
           trans_color->blue > sample_max)))
          png_warning(png_ptr,
             "tRNS chunk has out-of-range samples for bit_depth");
       info_ptr->trans_color = *trans_color;
       if (num_trans == 0)
          num_trans = 1;
    }
    info_ptr->num_trans = (png_uint_16)num_trans;
    if (num_trans != 0)
    {
       info_ptr->valid |= PNG_INFO_tRNS;
       info_ptr->free_me |= PNG_FREE_TRNS;
    }
 }
 #endif
 #ifdef PNG_sPLT_SUPPORTED
 void PNGAPI
 png_set_sPLT(png_const_structrp png_ptr,
     png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)
 /*
  *  entries        - array of png_sPLT_t structures
  *                   to be added to the list of palettes
  *                   in the info structure.
  *
  *  nentries       - number of palette structures to be
  *                   added.
  */
 {
    png_sPLT_tp np;
    if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
       return;
    /* Use the internal realloc function, which checks for all the possible
     * overflows.  Notice that the parameters are (int) and (size_t)
     */
    np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr,
       info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries,
       sizeof *np));
    if (np == NULL)
    {
       /* Out of memory or too many chunks */
       png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
       return;
    }
    png_free(png_ptr, info_ptr->splt_palettes);
    info_ptr->splt_palettes = np;
    info_ptr->free_me |= PNG_FREE_SPLT;
    np += info_ptr->splt_palettes_num;
    do
    {
       png_size_t length;
       /* Skip invalid input entries */
       if (entries->name == NULL || entries->entries == NULL)
       {
          /* png_handle_sPLT doesn't do this, so this is an app error */
          png_app_error(png_ptr, "png_set_sPLT: invalid sPLT");
          /* Just skip the invalid entry */
          continue;
       }
       np->depth = entries->depth;
       /* In the even of out-of-memory just return - there's no point keeping on
        * trying to add sPLT chunks.
        */
       length = strlen(entries->name) + 1;
       np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
       if (np->name == NULL)
          break;
       memcpy(np->name, entries->name, length);
       /* IMPORTANT: we have memory now that won't get freed if something else
        * goes wrong, this code must free it.  png_malloc_array produces no
        * warnings, use a png_chunk_report (below) if there is an error.
        */
       np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
           entries->nentries, sizeof (png_sPLT_entry)));
       if (np->entries == NULL)
       {
          png_free(png_ptr, np->name);
          break;
       }
       np->nentries = entries->nentries;
       /* This multiply can't overflow because png_malloc_array has already
        * checked it when doing the allocation.
        */
       memcpy(np->entries, entries->entries,
          entries->nentries * sizeof (png_sPLT_entry));
       /* Note that 'continue' skips the advance of the out pointer and out
        * count, so an invalid entry is not added.
        */
       info_ptr->valid |= PNG_INFO_sPLT;
       ++(info_ptr->splt_palettes_num);
       ++np;
    }
    while (++entries, --nentries);
    if (nentries > 0)
       png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
 }
 #endif /* PNG_sPLT_SUPPORTED */
 #ifdef PNG_APNG_SUPPORTED
 png_uint_32 PNGAPI
 png_set_acTL(png_structp png_ptr, png_infop info_ptr,
     png_uint_32 num_frames, png_uint_32 num_plays)
 {
     png_debug1(1, "in %s storage function", "acTL");
     if (png_ptr == NULL || info_ptr == NULL)
     {
         png_warning(png_ptr,
                     "Call to png_set_acTL() with NULL png_ptr "
                     "or info_ptr ignored");
         return (0);
     }
     if (num_frames == 0)
     {
         png_warning(png_ptr,
                     "Ignoring attempt to set acTL with num_frames zero");
         return (0);
     }
     if (num_frames > PNG_UINT_31_MAX)
     {
         png_warning(png_ptr,
                     "Ignoring attempt to set acTL with num_frames > 2^31-1");
         return (0);
     }
     if (num_plays > PNG_UINT_31_MAX)
     {
         png_warning(png_ptr,
                     "Ignoring attempt to set acTL with num_plays "
                     "> 2^31-1");
         return (0);
     }
     info_ptr->num_frames = num_frames;
     info_ptr->num_plays = num_plays;
     info_ptr->valid |= PNG_INFO_acTL;
     return (1);
 }
 /* delay_num and delay_den can hold any 16-bit values including zero */
 png_uint_32 PNGAPI
 png_set_next_frame_fcTL(png_structp png_ptr, png_infop info_ptr,
     png_uint_32 width, png_uint_32 height,
     png_uint_32 x_offset, png_uint_32 y_offset,
     png_uint_16 delay_num, png_uint_16 delay_den,
     png_byte dispose_op, png_byte blend_op)
 {
     png_debug1(1, "in %s storage function", "fcTL");
     if (png_ptr == NULL || info_ptr == NULL)
     {
         png_warning(png_ptr,
                     "Call to png_set_fcTL() with NULL png_ptr or info_ptr "
                     "ignored");
         return (0);
     }
     png_ensure_fcTL_is_valid(png_ptr, width, height, x_offset, y_offset,
                              delay_num, delay_den, dispose_op, blend_op);
     if (blend_op == PNG_BLEND_OP_OVER)
     {
         if (!(png_ptr->color_type & PNG_COLOR_MASK_ALPHA) &&
             !(png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
         {
           png_warning(png_ptr, "PNG_BLEND_OP_OVER is meaningless "
                                "and wasteful for opaque images, ignored");
           blend_op = PNG_BLEND_OP_SOURCE;
         }
     }
     info_ptr->next_frame_width = width;
     info_ptr->next_frame_height = height;
     info_ptr->next_frame_x_offset = x_offset;
     info_ptr->next_frame_y_offset = y_offset;
     info_ptr->next_frame_delay_num = delay_num;
     info_ptr->next_frame_delay_den = delay_den;
     info_ptr->next_frame_dispose_op = dispose_op;
     info_ptr->next_frame_blend_op = blend_op;
     info_ptr->valid |= PNG_INFO_fcTL;
     return (1);
 }
 void /* PRIVATE */
 png_ensure_fcTL_is_valid(png_structp png_ptr,
     png_uint_32 width, png_uint_32 height,
     png_uint_32 x_offset, png_uint_32 y_offset,
     png_uint_16 delay_num, png_uint_16 delay_den,
     png_byte dispose_op, png_byte blend_op)
 {
     if (width > PNG_UINT_31_MAX)
         png_error(png_ptr, "invalid width in fcTL (> 2^31-1)");
     if (height > PNG_UINT_31_MAX)
         png_error(png_ptr, "invalid height in fcTL (> 2^31-1)");
     if (x_offset > PNG_UINT_31_MAX)
         png_error(png_ptr, "invalid x_offset in fcTL (> 2^31-1)");
     if (y_offset > PNG_UINT_31_MAX)
         png_error(png_ptr, "invalid y_offset in fcTL (> 2^31-1)");
     if (width + x_offset > png_ptr->first_frame_width ||
         height + y_offset > png_ptr->first_frame_height)
         png_error(png_ptr, "dimensions of a frame are greater than"
                            "the ones in IHDR");
     if (dispose_op != PNG_DISPOSE_OP_NONE &&
         dispose_op != PNG_DISPOSE_OP_BACKGROUND &&
         dispose_op != PNG_DISPOSE_OP_PREVIOUS)
         png_error(png_ptr, "invalid dispose_op in fcTL");
     if (blend_op != PNG_BLEND_OP_SOURCE &&
         blend_op != PNG_BLEND_OP_OVER)
         png_error(png_ptr, "invalid blend_op in fcTL");
     PNG_UNUSED(delay_num)
     PNG_UNUSED(delay_den)
 }
 png_uint_32 PNGAPI
 png_set_first_frame_is_hidden(png_structp png_ptr, png_infop info_ptr,
                               png_byte is_hidden)
 {
     png_debug(1, "in png_first_frame_is_hidden()");
     if (png_ptr == NULL)
         return 0;
     if (is_hidden)
         png_ptr->apng_flags |= PNG_FIRST_FRAME_HIDDEN;
     else
         png_ptr->apng_flags &= ~PNG_FIRST_FRAME_HIDDEN;
     PNG_UNUSED(info_ptr)
     return 1;
 }
 #endif /* PNG_APNG_SUPPORTED */
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_byte
 check_location(png_const_structrp png_ptr, int location)
 {
    location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
    /* New in 1.6.0; copy the location and check it.  This is an API
     * change, previously the app had to use the
     * png_set_unknown_chunk_location API below for each chunk.
     */
    if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
    {
       /* Write struct, so unknown chunks come from the app */
       png_app_warning(png_ptr,
          "png_set_unknown_chunks now expects a valid location");
       /* Use the old behavior */
       location = (png_byte)(png_ptr->mode &
          (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT));
    }
    /* This need not be an internal error - if the app calls
     * png_set_unknown_chunks on a read pointer it must get the location right.
     */
    if (location == 0)
       png_error(png_ptr, "invalid location in png_set_unknown_chunks");
    /* Now reduce the location to the top-most set bit by removing each least
     * significant bit in turn.
     */
    while (location != (location & -location))
       location &= ~(location & -location);
    /* The cast is safe because 'location' is a bit mask and only the low four
     * bits are significant.
     */
    return (png_byte)location;
 }
 void PNGAPI
 png_set_unknown_chunks(png_const_structrp png_ptr,
    png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
 {
    png_unknown_chunkp np;
    if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
       unknowns == NULL)
       return;
    /* Check for the failure cases where support has been disabled at compile
     * time.  This code is hardly ever compiled - it's here because
     * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this
     * code) but may be meaningless if the read or write handling of unknown
     * chunks is not compiled in.
     */
 #  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
       defined(PNG_READ_SUPPORTED)
       if (png_ptr->mode & PNG_IS_READ_STRUCT)
       {
          png_app_error(png_ptr, "no unknown chunk support on read");
          return;
       }
 #  endif
 #  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
       defined(PNG_WRITE_SUPPORTED)
       if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
       {
          png_app_error(png_ptr, "no unknown chunk support on write");
          return;
       }
 #  endif
    /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that
     * unknown critical chunks could be lost with just a warning resulting in
     * undefined behavior.  Now png_chunk_report is used to provide behavior
     * appropriate to read or write.
     */
    np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr,
          info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns,
          sizeof *np));
    if (np == NULL)
    {
       png_chunk_report(png_ptr, "too many unknown chunks",
          PNG_CHUNK_WRITE_ERROR);
       return;
    }
    png_free(png_ptr, info_ptr->unknown_chunks);
    info_ptr->unknown_chunks = np; /* safe because it is initialized */
    info_ptr->free_me |= PNG_FREE_UNKN;
    np += info_ptr->unknown_chunks_num;
    /* Increment unknown_chunks_num each time round the loop to protect the
     * just-allocated chunk data.
     */
    for (; num_unknowns > 0; --num_unknowns, ++unknowns)
    {
       memcpy(np->name, unknowns->name, (sizeof np->name));
       np->name[(sizeof np->name)-1] = '\0';
       np->location = check_location(png_ptr, unknowns->location);
       if (unknowns->size == 0)
       {
          np->data = NULL;
          np->size = 0;
       }
       else
       {
          np->data = png_voidcast(png_bytep,
             png_malloc_base(png_ptr, unknowns->size));
          if (np->data == NULL)
          {
             png_chunk_report(png_ptr, "unknown chunk: out of memory",
                PNG_CHUNK_WRITE_ERROR);
             /* But just skip storing the unknown chunk */
             continue;
          }
          memcpy(np->data, unknowns->data, unknowns->size);
          np->size = unknowns->size;
       }
       /* These increments are skipped on out-of-memory for the data - the
        * unknown chunk entry gets overwritten if the png_chunk_report returns.
        * This is correct in the read case (the chunk is just dropped.)
        */
       ++np;
       ++(info_ptr->unknown_chunks_num);
    }
 }
 void PNGAPI
 png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
     int chunk, int location)
 {
    /* This API is pretty pointless in 1.6.0 because the location can be set
     * before the call to png_set_unknown_chunks.
     *
     * TODO: add a png_app_warning in 1.7
     */
    if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
       chunk < info_ptr->unknown_chunks_num)
    {
       if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0)
       {
          png_app_error(png_ptr, "invalid unknown chunk location");
          /* Fake out the pre 1.6.0 behavior: */
          if ((location & PNG_HAVE_IDAT)) /* undocumented! */
             location = PNG_AFTER_IDAT;
          else
             location = PNG_HAVE_IHDR; /* also undocumented */
       }
       info_ptr->unknown_chunks[chunk].location =
          check_location(png_ptr, location);
    }
 }
 #endif
 #ifdef PNG_MNG_FEATURES_SUPPORTED
 png_uint_32 PNGAPI
 png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
 {
    png_debug(1, "in png_permit_mng_features");
    if (png_ptr == NULL)
       return 0;
    png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES;
    return png_ptr->mng_features_permitted;
 }
 #endif
 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 static unsigned int
 add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
 {
    unsigned int i;
    /* Utility function: update the 'keep' state of a chunk if it is already in
     * the list, otherwise add it to the list.
     */
    for (i=0; i<count; ++i, list += 5) if (memcmp(list, add, 4) == 0)
    {
       list[4] = (png_byte)keep;
       return count;
    }
    if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
    {
       ++count;
       memcpy(list, add, 4);
       list[4] = (png_byte)keep;
    }
    return count;
 }
 void PNGAPI
 png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
     png_const_bytep chunk_list, int num_chunks_in)
 {
    png_bytep new_list;
    unsigned int num_chunks, old_num_chunks;
    if (png_ptr == NULL)
       return;
    if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
    {
       png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");
       return;
    }
    if (num_chunks_in <= 0)
    {
       png_ptr->unknown_default = keep;
       /* '0' means just set the flags, so stop here */
       if (num_chunks_in == 0)
         return;
    }
    if (num_chunks_in < 0)
    {
       /* Ignore all unknown chunks and all chunks recognized by
        * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
        */
       static PNG_CONST png_byte chunks_to_ignore[] = {
 ,  75,  71,  68, '\0',  /* bKGD */
 ,  72,  82,  77, '\0',  /* cHRM */
 ,  65,  77,  65, '\0',  /* gAMA */
 ,  73,  83,  84, '\0',  /* hIST */
 ,  67,  67,  80, '\0',  /* iCCP */
 ,  84,  88, 116, '\0',  /* iTXt */
 ,  70,  70, 115, '\0',  /* oFFs */
 ,  67,  65,  76, '\0',  /* pCAL */
 ,  72,  89, 115, '\0',  /* pHYs */
 ,  66,  73,  84, '\0',  /* sBIT */
 ,  67,  65,  76, '\0',  /* sCAL */
 ,  80,  76,  84, '\0',  /* sPLT */
 ,  84,  69,  82, '\0',  /* sTER */
 ,  82,  71,  66, '\0',  /* sRGB */
 ,  69,  88, 116, '\0',  /* tEXt */
 ,  73,  77,  69, '\0',  /* tIME */
 ,  84,  88, 116, '\0'   /* zTXt */
       };
       chunk_list = chunks_to_ignore;
       num_chunks = (sizeof chunks_to_ignore)/5;
    }
    else /* num_chunks_in > 0 */
    {
       if (chunk_list == NULL)
       {
          /* Prior to 1.6.0 this was silently ignored, now it is an app_error
           * which can be switched off.
           */
          png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");
          return;
       }
       num_chunks = num_chunks_in;
    }
    old_num_chunks = png_ptr->num_chunk_list;
    if (png_ptr->chunk_list == NULL)
       old_num_chunks = 0;
    /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow.
     */
    if (num_chunks + old_num_chunks > UINT_MAX/5)
    {
       png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");
       return;
    }
    /* If these chunks are being reset to the default then no more memory is
     * required because add_one_chunk above doesn't extend the list if the 'keep'
     * parameter is the default.
     */
    if (keep)
    {
       new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
 * (num_chunks + old_num_chunks)));
       if (old_num_chunks > 0)
          memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks);
    }
    else if (old_num_chunks > 0)
       new_list = png_ptr->chunk_list;
    else
       new_list = NULL;
    /* Add the new chunks together with each one's handling code.  If the chunk
     * already exists the code is updated, otherwise the chunk is added to the
     * end.  (In libpng 1.6.0 order no longer matters because this code enforces
     * the earlier convention that the last setting is the one that is used.)
     */
    if (new_list != NULL)
    {
       png_const_bytep inlist;
       png_bytep outlist;
       unsigned int i;
       for (i=0; i<num_chunks; ++i)
          old_num_chunks = add_one_chunk(new_list, old_num_chunks,
             chunk_list+5*i, keep);
       /* Now remove any spurious 'default' entries. */
       num_chunks = 0;
       for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
          if (inlist[4])
          {
             if (outlist != inlist)
                memcpy(outlist, inlist, 5);
             outlist += 5;
             ++num_chunks;
          }
       /* This means the application has removed all the specialized handling. */
       if (num_chunks == 0)
       {
          if (png_ptr->chunk_list != new_list)
             png_free(png_ptr, new_list);
          new_list = NULL;
       }
    }
    else
       num_chunks = 0;
    png_ptr->num_chunk_list = num_chunks;
    if (png_ptr->chunk_list != new_list)
    {
       if (png_ptr->chunk_list != NULL)
          png_free(png_ptr, png_ptr->chunk_list);
       png_ptr->chunk_list = new_list;
    }
 }
 #endif
 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
 void PNGAPI
 png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr,
     png_user_chunk_ptr read_user_chunk_fn)
 {
    png_debug(1, "in png_set_read_user_chunk_fn");
    if (png_ptr == NULL)
       return;
    png_ptr->read_user_chunk_fn = read_user_chunk_fn;
    png_ptr->user_chunk_ptr = user_chunk_ptr;
 }
 #endif
 #ifdef PNG_INFO_IMAGE_SUPPORTED
 void PNGAPI
 png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
     png_bytepp row_pointers)
 {
    png_debug1(1, "in %s storage function", "rows");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
    if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
    info_ptr->row_pointers = row_pointers;
    if (row_pointers)
       info_ptr->valid |= PNG_INFO_IDAT;
 }
 #endif
 void PNGAPI
 png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 {
     if (png_ptr == NULL)
        return;
     if (size == 0 || size > PNG_UINT_31_MAX)
        png_error(png_ptr, "invalid compression buffer size");
 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
       if (png_ptr->mode & PNG_IS_READ_STRUCT)
       {
          png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
          return;
       }
 #  endif
 #  ifdef PNG_WRITE_SUPPORTED
       if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
       {
          if (png_ptr->zowner != 0)
          {
             png_warning(png_ptr,
               "Compression buffer size cannot be changed because it is in use");
             return;
          }
          if (size > ZLIB_IO_MAX)
          {
             png_warning(png_ptr,
                "Compression buffer size limited to system maximum");
             size = ZLIB_IO_MAX; /* must fit */
          }
          else if (size < 6)
          {
             /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
              * if this is permitted.
              */
             png_warning(png_ptr,
                "Compression buffer size cannot be reduced below 6");
             return;
          }
          if (png_ptr->zbuffer_size != size)
          {
             png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
             png_ptr->zbuffer_size = (uInt)size;
          }
       }
 #  endif
 }
 void PNGAPI
 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
 {
    if (png_ptr && info_ptr)
       info_ptr->valid &= ~mask;
 }
 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
 /* This function was added to libpng 1.2.6 */
 void PNGAPI
 png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
     png_uint_32 user_height_max)
 {
    /* Images with dimensions larger than these limits will be
     * rejected by png_set_IHDR().  To accept any PNG datastream
     * regardless of dimensions, set both limits to 0x7ffffffL.
     */
    if (png_ptr == NULL)
       return;
    png_ptr->user_width_max = user_width_max;
    png_ptr->user_height_max = user_height_max;
 }
 /* This function was added to libpng 1.4.0 */
 void PNGAPI
 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
 {
     if (png_ptr)
        png_ptr->user_chunk_cache_max = user_chunk_cache_max;
 }
 /* This function was added to libpng 1.4.1 */
 void PNGAPI
 png_set_chunk_malloc_max (png_structrp png_ptr,
     png_alloc_size_t user_chunk_malloc_max)
 {
    if (png_ptr)
       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 void PNGAPI
 png_set_benign_errors(png_structrp png_ptr, int allowed)
 {
    png_debug(1, "in png_set_benign_errors");
    /* If allowed is 1, png_benign_error() is treated as a warning.
     *
     * If allowed is 0, png_benign_error() is treated as an error (which
     * is the default behavior if png_set_benign_errors() is not called).
     */
    if (allowed)
       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;
    else
       png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
 }
 #endif /* PNG_BENIGN_ERRORS_SUPPORTED */
 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
    /* Whether to report invalid palette index; added at libng-1.5.10.
     * It is possible for an indexed (color-type==3) PNG file to contain
     * pixels with invalid (out-of-range) indexes if the PLTE chunk has
     * fewer entries than the image's bit-depth would allow. We recover
     * from this gracefully by filling any incomplete palette with zeroes
     * (opaque black).  By default, when this occurs libpng will issue
     * a benign error.  This API can be used to override that behavior.
     */
 void PNGAPI
 png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
 {
    png_debug(1, "in png_set_check_for_invalid_index");
    if (allowed > 0)
       png_ptr->num_palette_max = 0;
    else
       png_ptr->num_palette_max = -1;
 }
 #endif
 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */

The Tor Browser / annotate

media/libpng/pngset.c@97036ab72558 (annotated)

media/libpng/pngset.c