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      1 
      2 /* pngset.c - storage of image information into info struct
      3  *
      4  * Last changed in libpng 1.6.24 [August 4, 2016]
      5  * Copyright (c) 1998-2016 Glenn Randers-Pehrson
      6  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
      7  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
      8  *
      9  * This code is released under the libpng license.
     10  * For conditions of distribution and use, see the disclaimer
     11  * and license in png.h
     12  *
     13  * The functions here are used during reads to store data from the file
     14  * into the info struct, and during writes to store application data
     15  * into the info struct for writing into the file.  This abstracts the
     16  * info struct and allows us to change the structure in the future.
     17  */
     18 
     19 #include "pngpriv.h"
     20 
     21 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
     22 
     23 #ifdef PNG_bKGD_SUPPORTED
     24 void PNGAPI
     25 png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
     26     png_const_color_16p background)
     27 {
     28    png_debug1(1, "in %s storage function", "bKGD");
     29 
     30    if (png_ptr == NULL || info_ptr == NULL || background == NULL)
     31       return;
     32 
     33    info_ptr->background = *background;
     34    info_ptr->valid |= PNG_INFO_bKGD;
     35 }
     36 #endif
     37 
     38 #ifdef PNG_cHRM_SUPPORTED
     39 void PNGFAPI
     40 png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
     41     png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
     42     png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
     43     png_fixed_point blue_x, png_fixed_point blue_y)
     44 {
     45    png_xy xy;
     46 
     47    png_debug1(1, "in %s storage function", "cHRM fixed");
     48 
     49    if (png_ptr == NULL || info_ptr == NULL)
     50       return;
     51 
     52    xy.redx = red_x;
     53    xy.redy = red_y;
     54    xy.greenx = green_x;
     55    xy.greeny = green_y;
     56    xy.bluex = blue_x;
     57    xy.bluey = blue_y;
     58    xy.whitex = white_x;
     59    xy.whitey = white_y;
     60 
     61    if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
     62        2/* override with app values*/) != 0)
     63       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
     64 
     65    png_colorspace_sync_info(png_ptr, info_ptr);
     66 }
     67 
     68 void PNGFAPI
     69 png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
     70     png_fixed_point int_red_X, png_fixed_point int_red_Y,
     71     png_fixed_point int_red_Z, png_fixed_point int_green_X,
     72     png_fixed_point int_green_Y, png_fixed_point int_green_Z,
     73     png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
     74     png_fixed_point int_blue_Z)
     75 {
     76    png_XYZ XYZ;
     77 
     78    png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
     79 
     80    if (png_ptr == NULL || info_ptr == NULL)
     81       return;
     82 
     83    XYZ.red_X = int_red_X;
     84    XYZ.red_Y = int_red_Y;
     85    XYZ.red_Z = int_red_Z;
     86    XYZ.green_X = int_green_X;
     87    XYZ.green_Y = int_green_Y;
     88    XYZ.green_Z = int_green_Z;
     89    XYZ.blue_X = int_blue_X;
     90    XYZ.blue_Y = int_blue_Y;
     91    XYZ.blue_Z = int_blue_Z;
     92 
     93    if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace,
     94        &XYZ, 2) != 0)
     95       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
     96 
     97    png_colorspace_sync_info(png_ptr, info_ptr);
     98 }
     99 
    100 #  ifdef PNG_FLOATING_POINT_SUPPORTED
    101 void PNGAPI
    102 png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
    103     double white_x, double white_y, double red_x, double red_y,
    104     double green_x, double green_y, double blue_x, double blue_y)
    105 {
    106    png_set_cHRM_fixed(png_ptr, info_ptr,
    107        png_fixed(png_ptr, white_x, "cHRM White X"),
    108        png_fixed(png_ptr, white_y, "cHRM White Y"),
    109        png_fixed(png_ptr, red_x, "cHRM Red X"),
    110        png_fixed(png_ptr, red_y, "cHRM Red Y"),
    111        png_fixed(png_ptr, green_x, "cHRM Green X"),
    112        png_fixed(png_ptr, green_y, "cHRM Green Y"),
    113        png_fixed(png_ptr, blue_x, "cHRM Blue X"),
    114        png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
    115 }
    116 
    117 void PNGAPI
    118 png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
    119     double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
    120     double blue_X, double blue_Y, double blue_Z)
    121 {
    122    png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
    123        png_fixed(png_ptr, red_X, "cHRM Red X"),
    124        png_fixed(png_ptr, red_Y, "cHRM Red Y"),
    125        png_fixed(png_ptr, red_Z, "cHRM Red Z"),
    126        png_fixed(png_ptr, green_X, "cHRM Green X"),
    127        png_fixed(png_ptr, green_Y, "cHRM Green Y"),
    128        png_fixed(png_ptr, green_Z, "cHRM Green Z"),
    129        png_fixed(png_ptr, blue_X, "cHRM Blue X"),
    130        png_fixed(png_ptr, blue_Y, "cHRM Blue Y"),
    131        png_fixed(png_ptr, blue_Z, "cHRM Blue Z"));
    132 }
    133 #  endif /* FLOATING_POINT */
    134 
    135 #endif /* cHRM */
    136 
    137 #ifdef PNG_gAMA_SUPPORTED
    138 void PNGFAPI
    139 png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    140     png_fixed_point file_gamma)
    141 {
    142    png_debug1(1, "in %s storage function", "gAMA");
    143 
    144    if (png_ptr == NULL || info_ptr == NULL)
    145       return;
    146 
    147    png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma);
    148    png_colorspace_sync_info(png_ptr, info_ptr);
    149 }
    150 
    151 #  ifdef PNG_FLOATING_POINT_SUPPORTED
    152 void PNGAPI
    153 png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma)
    154 {
    155    png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
    156        "png_set_gAMA"));
    157 }
    158 #  endif
    159 #endif
    160 
    161 #ifdef PNG_hIST_SUPPORTED
    162 void PNGAPI
    163 png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
    164     png_const_uint_16p hist)
    165 {
    166    int i;
    167 
    168    png_debug1(1, "in %s storage function", "hIST");
    169 
    170    if (png_ptr == NULL || info_ptr == NULL)
    171       return;
    172 
    173    if (info_ptr->num_palette == 0 || info_ptr->num_palette
    174        > PNG_MAX_PALETTE_LENGTH)
    175    {
    176       png_warning(png_ptr,
    177           "Invalid palette size, hIST allocation skipped");
    178 
    179       return;
    180    }
    181 
    182    png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
    183 
    184    /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
    185     * version 1.2.1
    186     */
    187    info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr,
    188        PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16))));
    189 
    190    if (info_ptr->hist == NULL)
    191    {
    192       png_warning(png_ptr, "Insufficient memory for hIST chunk data");
    193 
    194       return;
    195    }
    196 
    197    info_ptr->free_me |= PNG_FREE_HIST;
    198 
    199    for (i = 0; i < info_ptr->num_palette; i++)
    200       info_ptr->hist[i] = hist[i];
    201 
    202    info_ptr->valid |= PNG_INFO_hIST;
    203 }
    204 #endif
    205 
    206 void PNGAPI
    207 png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
    208     png_uint_32 width, png_uint_32 height, int bit_depth,
    209     int color_type, int interlace_type, int compression_type,
    210     int filter_type)
    211 {
    212    png_debug1(1, "in %s storage function", "IHDR");
    213 
    214    if (png_ptr == NULL || info_ptr == NULL)
    215       return;
    216 
    217    info_ptr->width = width;
    218    info_ptr->height = height;
    219    info_ptr->bit_depth = (png_byte)bit_depth;
    220    info_ptr->color_type = (png_byte)color_type;
    221    info_ptr->compression_type = (png_byte)compression_type;
    222    info_ptr->filter_type = (png_byte)filter_type;
    223    info_ptr->interlace_type = (png_byte)interlace_type;
    224 
    225    png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
    226        info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
    227        info_ptr->compression_type, info_ptr->filter_type);
    228 
    229    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
    230       info_ptr->channels = 1;
    231 
    232    else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
    233       info_ptr->channels = 3;
    234 
    235    else
    236       info_ptr->channels = 1;
    237 
    238    if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
    239       info_ptr->channels++;
    240 
    241    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
    242 
    243    info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
    244 }
    245 
    246 #ifdef PNG_oFFs_SUPPORTED
    247 void PNGAPI
    248 png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr,
    249     png_int_32 offset_x, png_int_32 offset_y, int unit_type)
    250 {
    251    png_debug1(1, "in %s storage function", "oFFs");
    252 
    253    if (png_ptr == NULL || info_ptr == NULL)
    254       return;
    255 
    256    info_ptr->x_offset = offset_x;
    257    info_ptr->y_offset = offset_y;
    258    info_ptr->offset_unit_type = (png_byte)unit_type;
    259    info_ptr->valid |= PNG_INFO_oFFs;
    260 }
    261 #endif
    262 
    263 #ifdef PNG_pCAL_SUPPORTED
    264 void PNGAPI
    265 png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
    266     png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
    267     int nparams, png_const_charp units, png_charpp params)
    268 {
    269    png_size_t length;
    270    int i;
    271 
    272    png_debug1(1, "in %s storage function", "pCAL");
    273 
    274    if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
    275        || (nparams > 0 && params == NULL))
    276       return;
    277 
    278    length = strlen(purpose) + 1;
    279    png_debug1(3, "allocating purpose for info (%lu bytes)",
    280        (unsigned long)length);
    281 
    282    /* TODO: validate format of calibration name and unit name */
    283 
    284    /* Check that the type matches the specification. */
    285    if (type < 0 || type > 3)
    286       png_error(png_ptr, "Invalid pCAL equation type");
    287 
    288    if (nparams < 0 || nparams > 255)
    289       png_error(png_ptr, "Invalid pCAL parameter count");
    290 
    291    /* Validate params[nparams] */
    292    for (i=0; i<nparams; ++i)
    293    {
    294       if (params[i] == NULL ||
    295           !png_check_fp_string(params[i], strlen(params[i])))
    296          png_error(png_ptr, "Invalid format for pCAL parameter");
    297    }
    298 
    299    info_ptr->pcal_purpose = png_voidcast(png_charp,
    300        png_malloc_warn(png_ptr, length));
    301 
    302    if (info_ptr->pcal_purpose == NULL)
    303    {
    304       png_warning(png_ptr, "Insufficient memory for pCAL purpose");
    305 
    306       return;
    307    }
    308 
    309    memcpy(info_ptr->pcal_purpose, purpose, length);
    310 
    311    png_debug(3, "storing X0, X1, type, and nparams in info");
    312    info_ptr->pcal_X0 = X0;
    313    info_ptr->pcal_X1 = X1;
    314    info_ptr->pcal_type = (png_byte)type;
    315    info_ptr->pcal_nparams = (png_byte)nparams;
    316 
    317    length = strlen(units) + 1;
    318    png_debug1(3, "allocating units for info (%lu bytes)",
    319        (unsigned long)length);
    320 
    321    info_ptr->pcal_units = png_voidcast(png_charp,
    322        png_malloc_warn(png_ptr, length));
    323 
    324    if (info_ptr->pcal_units == NULL)
    325    {
    326       png_warning(png_ptr, "Insufficient memory for pCAL units");
    327 
    328       return;
    329    }
    330 
    331    memcpy(info_ptr->pcal_units, units, length);
    332 
    333    info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
    334        (png_size_t)((nparams + 1) * (sizeof (png_charp)))));
    335 
    336    if (info_ptr->pcal_params == NULL)
    337    {
    338       png_warning(png_ptr, "Insufficient memory for pCAL params");
    339 
    340       return;
    341    }
    342 
    343    memset(info_ptr->pcal_params, 0, (nparams + 1) * (sizeof (png_charp)));
    344 
    345    for (i = 0; i < nparams; i++)
    346    {
    347       length = strlen(params[i]) + 1;
    348       png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
    349           (unsigned long)length);
    350 
    351       info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
    352 
    353       if (info_ptr->pcal_params[i] == NULL)
    354       {
    355          png_warning(png_ptr, "Insufficient memory for pCAL parameter");
    356 
    357          return;
    358       }
    359 
    360       memcpy(info_ptr->pcal_params[i], params[i], length);
    361    }
    362 
    363    info_ptr->valid |= PNG_INFO_pCAL;
    364    info_ptr->free_me |= PNG_FREE_PCAL;
    365 }
    366 #endif
    367 
    368 #ifdef PNG_sCAL_SUPPORTED
    369 void PNGAPI
    370 png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
    371     int unit, png_const_charp swidth, png_const_charp sheight)
    372 {
    373    png_size_t lengthw = 0, lengthh = 0;
    374 
    375    png_debug1(1, "in %s storage function", "sCAL");
    376 
    377    if (png_ptr == NULL || info_ptr == NULL)
    378       return;
    379 
    380    /* Double check the unit (should never get here with an invalid
    381     * unit unless this is an API call.)
    382     */
    383    if (unit != 1 && unit != 2)
    384       png_error(png_ptr, "Invalid sCAL unit");
    385 
    386    if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
    387        swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
    388       png_error(png_ptr, "Invalid sCAL width");
    389 
    390    if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
    391        sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
    392       png_error(png_ptr, "Invalid sCAL height");
    393 
    394    info_ptr->scal_unit = (png_byte)unit;
    395 
    396    ++lengthw;
    397 
    398    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
    399 
    400    info_ptr->scal_s_width = png_voidcast(png_charp,
    401        png_malloc_warn(png_ptr, lengthw));
    402 
    403    if (info_ptr->scal_s_width == NULL)
    404    {
    405       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
    406 
    407       return;
    408    }
    409 
    410    memcpy(info_ptr->scal_s_width, swidth, lengthw);
    411 
    412    ++lengthh;
    413 
    414    png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
    415 
    416    info_ptr->scal_s_height = png_voidcast(png_charp,
    417        png_malloc_warn(png_ptr, lengthh));
    418 
    419    if (info_ptr->scal_s_height == NULL)
    420    {
    421       png_free (png_ptr, info_ptr->scal_s_width);
    422       info_ptr->scal_s_width = NULL;
    423 
    424       png_warning(png_ptr, "Memory allocation failed while processing sCAL");
    425 
    426       return;
    427    }
    428 
    429    memcpy(info_ptr->scal_s_height, sheight, lengthh);
    430 
    431    info_ptr->valid |= PNG_INFO_sCAL;
    432    info_ptr->free_me |= PNG_FREE_SCAL;
    433 }
    434 
    435 #  ifdef PNG_FLOATING_POINT_SUPPORTED
    436 void PNGAPI
    437 png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
    438     double width, double height)
    439 {
    440    png_debug1(1, "in %s storage function", "sCAL");
    441 
    442    /* Check the arguments. */
    443    if (width <= 0)
    444       png_warning(png_ptr, "Invalid sCAL width ignored");
    445 
    446    else if (height <= 0)
    447       png_warning(png_ptr, "Invalid sCAL height ignored");
    448 
    449    else
    450    {
    451       /* Convert 'width' and 'height' to ASCII. */
    452       char swidth[PNG_sCAL_MAX_DIGITS+1];
    453       char sheight[PNG_sCAL_MAX_DIGITS+1];
    454 
    455       png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width,
    456           PNG_sCAL_PRECISION);
    457       png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height,
    458           PNG_sCAL_PRECISION);
    459 
    460       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
    461    }
    462 }
    463 #  endif
    464 
    465 #  ifdef PNG_FIXED_POINT_SUPPORTED
    466 void PNGAPI
    467 png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
    468     png_fixed_point width, png_fixed_point height)
    469 {
    470    png_debug1(1, "in %s storage function", "sCAL");
    471 
    472    /* Check the arguments. */
    473    if (width <= 0)
    474       png_warning(png_ptr, "Invalid sCAL width ignored");
    475 
    476    else if (height <= 0)
    477       png_warning(png_ptr, "Invalid sCAL height ignored");
    478 
    479    else
    480    {
    481       /* Convert 'width' and 'height' to ASCII. */
    482       char swidth[PNG_sCAL_MAX_DIGITS+1];
    483       char sheight[PNG_sCAL_MAX_DIGITS+1];
    484 
    485       png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width);
    486       png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height);
    487 
    488       png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
    489    }
    490 }
    491 #  endif
    492 #endif
    493 
    494 #ifdef PNG_pHYs_SUPPORTED
    495 void PNGAPI
    496 png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr,
    497     png_uint_32 res_x, png_uint_32 res_y, int unit_type)
    498 {
    499    png_debug1(1, "in %s storage function", "pHYs");
    500 
    501    if (png_ptr == NULL || info_ptr == NULL)
    502       return;
    503 
    504    info_ptr->x_pixels_per_unit = res_x;
    505    info_ptr->y_pixels_per_unit = res_y;
    506    info_ptr->phys_unit_type = (png_byte)unit_type;
    507    info_ptr->valid |= PNG_INFO_pHYs;
    508 }
    509 #endif
    510 
    511 void PNGAPI
    512 png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
    513     png_const_colorp palette, int num_palette)
    514 {
    515 
    516    png_uint_32 max_palette_length;
    517 
    518    png_debug1(1, "in %s storage function", "PLTE");
    519 
    520    if (png_ptr == NULL || info_ptr == NULL)
    521       return;
    522 
    523    max_palette_length = (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
    524       (1 << info_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;
    525 
    526    if (num_palette < 0 || num_palette > (int) max_palette_length)
    527    {
    528       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
    529          png_error(png_ptr, "Invalid palette length");
    530 
    531       else
    532       {
    533          png_warning(png_ptr, "Invalid palette length");
    534 
    535          return;
    536       }
    537    }
    538 
    539    if ((num_palette > 0 && palette == NULL) ||
    540       (num_palette == 0
    541 #        ifdef PNG_MNG_FEATURES_SUPPORTED
    542             && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0
    543 #        endif
    544       ))
    545    {
    546       png_error(png_ptr, "Invalid palette");
    547    }
    548 
    549    /* It may not actually be necessary to set png_ptr->palette here;
    550     * we do it for backward compatibility with the way the png_handle_tRNS
    551     * function used to do the allocation.
    552     *
    553     * 1.6.0: the above statement appears to be incorrect; something has to set
    554     * the palette inside png_struct on read.
    555     */
    556    png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
    557 
    558    /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
    559     * of num_palette entries, in case of an invalid PNG file or incorrect
    560     * call to png_set_PLTE() with too-large sample values.
    561     */
    562    png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
    563        PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));
    564 
    565    if (num_palette > 0)
    566       memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
    567    info_ptr->palette = png_ptr->palette;
    568    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
    569 
    570    info_ptr->free_me |= PNG_FREE_PLTE;
    571 
    572    info_ptr->valid |= PNG_INFO_PLTE;
    573 }
    574 
    575 #ifdef PNG_sBIT_SUPPORTED
    576 void PNGAPI
    577 png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
    578     png_const_color_8p sig_bit)
    579 {
    580    png_debug1(1, "in %s storage function", "sBIT");
    581 
    582    if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL)
    583       return;
    584 
    585    info_ptr->sig_bit = *sig_bit;
    586    info_ptr->valid |= PNG_INFO_sBIT;
    587 }
    588 #endif
    589 
    590 #ifdef PNG_sRGB_SUPPORTED
    591 void PNGAPI
    592 png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent)
    593 {
    594    png_debug1(1, "in %s storage function", "sRGB");
    595 
    596    if (png_ptr == NULL || info_ptr == NULL)
    597       return;
    598 
    599    (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent);
    600    png_colorspace_sync_info(png_ptr, info_ptr);
    601 }
    602 
    603 void PNGAPI
    604 png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
    605     int srgb_intent)
    606 {
    607    png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
    608 
    609    if (png_ptr == NULL || info_ptr == NULL)
    610       return;
    611 
    612    if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace,
    613        srgb_intent) != 0)
    614    {
    615       /* This causes the gAMA and cHRM to be written too */
    616       info_ptr->colorspace.flags |=
    617          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
    618    }
    619 
    620    png_colorspace_sync_info(png_ptr, info_ptr);
    621 }
    622 #endif /* sRGB */
    623 
    624 
    625 #ifdef PNG_iCCP_SUPPORTED
    626 void PNGAPI
    627 png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
    628     png_const_charp name, int compression_type,
    629     png_const_bytep profile, png_uint_32 proflen)
    630 {
    631    png_charp new_iccp_name;
    632    png_bytep new_iccp_profile;
    633    png_size_t length;
    634 
    635    png_debug1(1, "in %s storage function", "iCCP");
    636 
    637    if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
    638       return;
    639 
    640    if (compression_type != PNG_COMPRESSION_TYPE_BASE)
    641       png_app_error(png_ptr, "Invalid iCCP compression method");
    642 
    643    /* Set the colorspace first because this validates the profile; do not
    644     * override previously set app cHRM or gAMA here (because likely as not the
    645     * application knows better than libpng what the correct values are.)  Pass
    646     * the info_ptr color_type field to png_colorspace_set_ICC because in the
    647     * write case it has not yet been stored in png_ptr.
    648     */
    649    {
    650       int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
    651           proflen, profile, info_ptr->color_type);
    652 
    653       png_colorspace_sync_info(png_ptr, info_ptr);
    654 
    655       /* Don't do any of the copying if the profile was bad, or inconsistent. */
    656       if (result == 0)
    657          return;
    658 
    659       /* But do write the gAMA and cHRM chunks from the profile. */
    660       info_ptr->colorspace.flags |=
    661          PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
    662    }
    663 
    664    length = strlen(name)+1;
    665    new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));
    666 
    667    if (new_iccp_name == NULL)
    668    {
    669       png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
    670 
    671       return;
    672    }
    673 
    674    memcpy(new_iccp_name, name, length);
    675    new_iccp_profile = png_voidcast(png_bytep,
    676        png_malloc_warn(png_ptr, proflen));
    677 
    678    if (new_iccp_profile == NULL)
    679    {
    680       png_free(png_ptr, new_iccp_name);
    681       png_benign_error(png_ptr,
    682           "Insufficient memory to process iCCP profile");
    683 
    684       return;
    685    }
    686 
    687    memcpy(new_iccp_profile, profile, proflen);
    688 
    689    png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
    690 
    691    info_ptr->iccp_proflen = proflen;
    692    info_ptr->iccp_name = new_iccp_name;
    693    info_ptr->iccp_profile = new_iccp_profile;
    694    info_ptr->free_me |= PNG_FREE_ICCP;
    695    info_ptr->valid |= PNG_INFO_iCCP;
    696 }
    697 #endif
    698 
    699 #ifdef PNG_TEXT_SUPPORTED
    700 void PNGAPI
    701 png_set_text(png_const_structrp png_ptr, png_inforp info_ptr,
    702     png_const_textp text_ptr, int num_text)
    703 {
    704    int ret;
    705    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
    706 
    707    if (ret != 0)
    708       png_error(png_ptr, "Insufficient memory to store text");
    709 }
    710 
    711 int /* PRIVATE */
    712 png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
    713     png_const_textp text_ptr, int num_text)
    714 {
    715    int i;
    716 
    717    png_debug1(1, "in %lx storage function", png_ptr == NULL ? 0xabadca11U :
    718       (unsigned long)png_ptr->chunk_name);
    719 
    720    if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
    721       return(0);
    722 
    723    /* Make sure we have enough space in the "text" array in info_struct
    724     * to hold all of the incoming text_ptr objects.  This compare can't overflow
    725     * because max_text >= num_text (anyway, subtract of two positive integers
    726     * can't overflow in any case.)
    727     */
    728    if (num_text > info_ptr->max_text - info_ptr->num_text)
    729    {
    730       int old_num_text = info_ptr->num_text;
    731       int max_text;
    732       png_textp new_text = NULL;
    733 
    734       /* Calculate an appropriate max_text, checking for overflow. */
    735       max_text = old_num_text;
    736       if (num_text <= INT_MAX - max_text)
    737       {
    738          max_text += num_text;
    739 
    740          /* Round up to a multiple of 8 */
    741          if (max_text < INT_MAX-8)
    742             max_text = (max_text + 8) & ~0x7;
    743 
    744          else
    745             max_text = INT_MAX;
    746 
    747          /* Now allocate a new array and copy the old members in; this does all
    748           * the overflow checks.
    749           */
    750          new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
    751              info_ptr->text, old_num_text, max_text-old_num_text,
    752              sizeof *new_text));
    753       }
    754 
    755       if (new_text == NULL)
    756       {
    757          png_chunk_report(png_ptr, "too many text chunks",
    758              PNG_CHUNK_WRITE_ERROR);
    759 
    760          return 1;
    761       }
    762 
    763       png_free(png_ptr, info_ptr->text);
    764 
    765       info_ptr->text = new_text;
    766       info_ptr->free_me |= PNG_FREE_TEXT;
    767       info_ptr->max_text = max_text;
    768       /* num_text is adjusted below as the entries are copied in */
    769 
    770       png_debug1(3, "allocated %d entries for info_ptr->text", max_text);
    771    }
    772 
    773    for (i = 0; i < num_text; i++)
    774    {
    775       size_t text_length, key_len;
    776       size_t lang_len, lang_key_len;
    777       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
    778 
    779       if (text_ptr[i].key == NULL)
    780           continue;
    781 
    782       if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
    783           text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
    784       {
    785          png_chunk_report(png_ptr, "text compression mode is out of range",
    786              PNG_CHUNK_WRITE_ERROR);
    787          continue;
    788       }
    789 
    790       key_len = strlen(text_ptr[i].key);
    791 
    792       if (text_ptr[i].compression <= 0)
    793       {
    794          lang_len = 0;
    795          lang_key_len = 0;
    796       }
    797 
    798       else
    799 #  ifdef PNG_iTXt_SUPPORTED
    800       {
    801          /* Set iTXt data */
    802 
    803          if (text_ptr[i].lang != NULL)
    804             lang_len = strlen(text_ptr[i].lang);
    805 
    806          else
    807             lang_len = 0;
    808 
    809          if (text_ptr[i].lang_key != NULL)
    810             lang_key_len = strlen(text_ptr[i].lang_key);
    811 
    812          else
    813             lang_key_len = 0;
    814       }
    815 #  else /* iTXt */
    816       {
    817          png_chunk_report(png_ptr, "iTXt chunk not supported",
    818              PNG_CHUNK_WRITE_ERROR);
    819          continue;
    820       }
    821 #  endif
    822 
    823       if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
    824       {
    825          text_length = 0;
    826 #  ifdef PNG_iTXt_SUPPORTED
    827          if (text_ptr[i].compression > 0)
    828             textp->compression = PNG_ITXT_COMPRESSION_NONE;
    829 
    830          else
    831 #  endif
    832             textp->compression = PNG_TEXT_COMPRESSION_NONE;
    833       }
    834 
    835       else
    836       {
    837          text_length = strlen(text_ptr[i].text);
    838          textp->compression = text_ptr[i].compression;
    839       }
    840 
    841       textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr,
    842           key_len + text_length + lang_len + lang_key_len + 4));
    843 
    844       if (textp->key == NULL)
    845       {
    846          png_chunk_report(png_ptr, "text chunk: out of memory",
    847              PNG_CHUNK_WRITE_ERROR);
    848 
    849          return 1;
    850       }
    851 
    852       png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
    853           (unsigned long)(png_uint_32)
    854           (key_len + lang_len + lang_key_len + text_length + 4),
    855           textp->key);
    856 
    857       memcpy(textp->key, text_ptr[i].key, key_len);
    858       *(textp->key + key_len) = '\0';
    859 
    860       if (text_ptr[i].compression > 0)
    861       {
    862          textp->lang = textp->key + key_len + 1;
    863          memcpy(textp->lang, text_ptr[i].lang, lang_len);
    864          *(textp->lang + lang_len) = '\0';
    865          textp->lang_key = textp->lang + lang_len + 1;
    866          memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
    867          *(textp->lang_key + lang_key_len) = '\0';
    868          textp->text = textp->lang_key + lang_key_len + 1;
    869       }
    870 
    871       else
    872       {
    873          textp->lang=NULL;
    874          textp->lang_key=NULL;
    875          textp->text = textp->key + key_len + 1;
    876       }
    877 
    878       if (text_length != 0)
    879          memcpy(textp->text, text_ptr[i].text, text_length);
    880 
    881       *(textp->text + text_length) = '\0';
    882 
    883 #  ifdef PNG_iTXt_SUPPORTED
    884       if (textp->compression > 0)
    885       {
    886          textp->text_length = 0;
    887          textp->itxt_length = text_length;
    888       }
    889 
    890       else
    891 #  endif
    892       {
    893          textp->text_length = text_length;
    894          textp->itxt_length = 0;
    895       }
    896 
    897       info_ptr->num_text++;
    898       png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
    899    }
    900 
    901    return(0);
    902 }
    903 #endif
    904 
    905 #ifdef PNG_tIME_SUPPORTED
    906 void PNGAPI
    907 png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
    908     png_const_timep mod_time)
    909 {
    910    png_debug1(1, "in %s storage function", "tIME");
    911 
    912    if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
    913        (png_ptr->mode & PNG_WROTE_tIME) != 0)
    914       return;
    915 
    916    if (mod_time->month == 0   || mod_time->month > 12  ||
    917        mod_time->day   == 0   || mod_time->day   > 31  ||
    918        mod_time->hour  > 23   || mod_time->minute > 59 ||
    919        mod_time->second > 60)
    920    {
    921       png_warning(png_ptr, "Ignoring invalid time value");
    922 
    923       return;
    924    }
    925 
    926    info_ptr->mod_time = *mod_time;
    927    info_ptr->valid |= PNG_INFO_tIME;
    928 }
    929 #endif
    930 
    931 #ifdef PNG_tRNS_SUPPORTED
    932 void PNGAPI
    933 png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
    934     png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
    935 {
    936    png_debug1(1, "in %s storage function", "tRNS");
    937 
    938    if (png_ptr == NULL || info_ptr == NULL)
    939 
    940       return;
    941 
    942    if (trans_alpha != NULL)
    943    {
    944        /* It may not actually be necessary to set png_ptr->trans_alpha here;
    945         * we do it for backward compatibility with the way the png_handle_tRNS
    946         * function used to do the allocation.
    947         *
    948         * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
    949         * relies on png_set_tRNS storing the information in png_struct
    950         * (otherwise it won't be there for the code in pngrtran.c).
    951         */
    952 
    953        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
    954 
    955        if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
    956        {
    957          /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
    958           info_ptr->trans_alpha = png_voidcast(png_bytep,
    959               png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
    960           memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
    961        }
    962        png_ptr->trans_alpha = info_ptr->trans_alpha;
    963    }
    964 
    965    if (trans_color != NULL)
    966    {
    967 #ifdef PNG_WARNINGS_SUPPORTED
    968       if (info_ptr->bit_depth < 16)
    969       {
    970          int sample_max = (1 << info_ptr->bit_depth) - 1;
    971 
    972          if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
    973              trans_color->gray > sample_max) ||
    974              (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
    975              (trans_color->red > sample_max ||
    976              trans_color->green > sample_max ||
    977              trans_color->blue > sample_max)))
    978             png_warning(png_ptr,
    979                 "tRNS chunk has out-of-range samples for bit_depth");
    980       }
    981 #endif
    982 
    983       info_ptr->trans_color = *trans_color;
    984 
    985       if (num_trans == 0)
    986          num_trans = 1;
    987    }
    988 
    989    info_ptr->num_trans = (png_uint_16)num_trans;
    990 
    991    if (num_trans != 0)
    992    {
    993       info_ptr->valid |= PNG_INFO_tRNS;
    994       info_ptr->free_me |= PNG_FREE_TRNS;
    995    }
    996 }
    997 #endif
    998 
    999 #ifdef PNG_sPLT_SUPPORTED
   1000 void PNGAPI
   1001 png_set_sPLT(png_const_structrp png_ptr,
   1002     png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)
   1003 /*
   1004  *  entries        - array of png_sPLT_t structures
   1005  *                   to be added to the list of palettes
   1006  *                   in the info structure.
   1007  *
   1008  *  nentries       - number of palette structures to be
   1009  *                   added.
   1010  */
   1011 {
   1012    png_sPLT_tp np;
   1013 
   1014    if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
   1015       return;
   1016 
   1017    /* Use the internal realloc function, which checks for all the possible
   1018     * overflows.  Notice that the parameters are (int) and (size_t)
   1019     */
   1020    np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr,
   1021        info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries,
   1022        sizeof *np));
   1023 
   1024    if (np == NULL)
   1025    {
   1026       /* Out of memory or too many chunks */
   1027       png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
   1028 
   1029       return;
   1030    }
   1031 
   1032    png_free(png_ptr, info_ptr->splt_palettes);
   1033    info_ptr->splt_palettes = np;
   1034    info_ptr->free_me |= PNG_FREE_SPLT;
   1035 
   1036    np += info_ptr->splt_palettes_num;
   1037 
   1038    do
   1039    {
   1040       png_size_t length;
   1041 
   1042       /* Skip invalid input entries */
   1043       if (entries->name == NULL || entries->entries == NULL)
   1044       {
   1045          /* png_handle_sPLT doesn't do this, so this is an app error */
   1046          png_app_error(png_ptr, "png_set_sPLT: invalid sPLT");
   1047          /* Just skip the invalid entry */
   1048          continue;
   1049       }
   1050 
   1051       np->depth = entries->depth;
   1052 
   1053       /* In the event of out-of-memory just return - there's no point keeping
   1054        * on trying to add sPLT chunks.
   1055        */
   1056       length = strlen(entries->name) + 1;
   1057       np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
   1058 
   1059       if (np->name == NULL)
   1060          break;
   1061 
   1062       memcpy(np->name, entries->name, length);
   1063 
   1064       /* IMPORTANT: we have memory now that won't get freed if something else
   1065        * goes wrong; this code must free it.  png_malloc_array produces no
   1066        * warnings; use a png_chunk_report (below) if there is an error.
   1067        */
   1068       np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
   1069           entries->nentries, sizeof (png_sPLT_entry)));
   1070 
   1071       if (np->entries == NULL)
   1072       {
   1073          png_free(png_ptr, np->name);
   1074          np->name = NULL;
   1075          break;
   1076       }
   1077 
   1078       np->nentries = entries->nentries;
   1079       /* This multiply can't overflow because png_malloc_array has already
   1080        * checked it when doing the allocation.
   1081        */
   1082       memcpy(np->entries, entries->entries,
   1083           entries->nentries * sizeof (png_sPLT_entry));
   1084 
   1085       /* Note that 'continue' skips the advance of the out pointer and out
   1086        * count, so an invalid entry is not added.
   1087        */
   1088       info_ptr->valid |= PNG_INFO_sPLT;
   1089       ++(info_ptr->splt_palettes_num);
   1090       ++np;
   1091    }
   1092    while (++entries, --nentries);
   1093 
   1094    if (nentries > 0)
   1095       png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
   1096 }
   1097 #endif /* sPLT */
   1098 
   1099 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
   1100 static png_byte
   1101 check_location(png_const_structrp png_ptr, int location)
   1102 {
   1103    location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
   1104 
   1105    /* New in 1.6.0; copy the location and check it.  This is an API
   1106     * change; previously the app had to use the
   1107     * png_set_unknown_chunk_location API below for each chunk.
   1108     */
   1109    if (location == 0 && (png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   1110    {
   1111       /* Write struct, so unknown chunks come from the app */
   1112       png_app_warning(png_ptr,
   1113           "png_set_unknown_chunks now expects a valid location");
   1114       /* Use the old behavior */
   1115       location = (png_byte)(png_ptr->mode &
   1116           (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT));
   1117    }
   1118 
   1119    /* This need not be an internal error - if the app calls
   1120     * png_set_unknown_chunks on a read pointer it must get the location right.
   1121     */
   1122    if (location == 0)
   1123       png_error(png_ptr, "invalid location in png_set_unknown_chunks");
   1124 
   1125    /* Now reduce the location to the top-most set bit by removing each least
   1126     * significant bit in turn.
   1127     */
   1128    while (location != (location & -location))
   1129       location &= ~(location & -location);
   1130 
   1131    /* The cast is safe because 'location' is a bit mask and only the low four
   1132     * bits are significant.
   1133     */
   1134    return (png_byte)location;
   1135 }
   1136 
   1137 void PNGAPI
   1138 png_set_unknown_chunks(png_const_structrp png_ptr,
   1139     png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
   1140 {
   1141    png_unknown_chunkp np;
   1142 
   1143    if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
   1144        unknowns == NULL)
   1145       return;
   1146 
   1147    /* Check for the failure cases where support has been disabled at compile
   1148     * time.  This code is hardly ever compiled - it's here because
   1149     * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this
   1150     * code) but may be meaningless if the read or write handling of unknown
   1151     * chunks is not compiled in.
   1152     */
   1153 #  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
   1154       defined(PNG_READ_SUPPORTED)
   1155       if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
   1156       {
   1157          png_app_error(png_ptr, "no unknown chunk support on read");
   1158 
   1159          return;
   1160       }
   1161 #  endif
   1162 #  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
   1163       defined(PNG_WRITE_SUPPORTED)
   1164       if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   1165       {
   1166          png_app_error(png_ptr, "no unknown chunk support on write");
   1167 
   1168          return;
   1169       }
   1170 #  endif
   1171 
   1172    /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that
   1173     * unknown critical chunks could be lost with just a warning resulting in
   1174     * undefined behavior.  Now png_chunk_report is used to provide behavior
   1175     * appropriate to read or write.
   1176     */
   1177    np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr,
   1178        info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns,
   1179        sizeof *np));
   1180 
   1181    if (np == NULL)
   1182    {
   1183       png_chunk_report(png_ptr, "too many unknown chunks",
   1184           PNG_CHUNK_WRITE_ERROR);
   1185 
   1186       return;
   1187    }
   1188 
   1189    png_free(png_ptr, info_ptr->unknown_chunks);
   1190    info_ptr->unknown_chunks = np; /* safe because it is initialized */
   1191    info_ptr->free_me |= PNG_FREE_UNKN;
   1192 
   1193    np += info_ptr->unknown_chunks_num;
   1194 
   1195    /* Increment unknown_chunks_num each time round the loop to protect the
   1196     * just-allocated chunk data.
   1197     */
   1198    for (; num_unknowns > 0; --num_unknowns, ++unknowns)
   1199    {
   1200       memcpy(np->name, unknowns->name, (sizeof np->name));
   1201       np->name[(sizeof np->name)-1] = '\0';
   1202       np->location = check_location(png_ptr, unknowns->location);
   1203 
   1204       if (unknowns->size == 0)
   1205       {
   1206          np->data = NULL;
   1207          np->size = 0;
   1208       }
   1209 
   1210       else
   1211       {
   1212          np->data = png_voidcast(png_bytep,
   1213              png_malloc_base(png_ptr, unknowns->size));
   1214 
   1215          if (np->data == NULL)
   1216          {
   1217             png_chunk_report(png_ptr, "unknown chunk: out of memory",
   1218                 PNG_CHUNK_WRITE_ERROR);
   1219             /* But just skip storing the unknown chunk */
   1220             continue;
   1221          }
   1222 
   1223          memcpy(np->data, unknowns->data, unknowns->size);
   1224          np->size = unknowns->size;
   1225       }
   1226 
   1227       /* These increments are skipped on out-of-memory for the data - the
   1228        * unknown chunk entry gets overwritten if the png_chunk_report returns.
   1229        * This is correct in the read case (the chunk is just dropped.)
   1230        */
   1231       ++np;
   1232       ++(info_ptr->unknown_chunks_num);
   1233    }
   1234 }
   1235 
   1236 void PNGAPI
   1237 png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
   1238     int chunk, int location)
   1239 {
   1240    /* This API is pretty pointless in 1.6.0 because the location can be set
   1241     * before the call to png_set_unknown_chunks.
   1242     *
   1243     * TODO: add a png_app_warning in 1.7
   1244     */
   1245    if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
   1246       chunk < info_ptr->unknown_chunks_num)
   1247    {
   1248       if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0)
   1249       {
   1250          png_app_error(png_ptr, "invalid unknown chunk location");
   1251          /* Fake out the pre 1.6.0 behavior: */
   1252          if ((location & PNG_HAVE_IDAT) != 0) /* undocumented! */
   1253             location = PNG_AFTER_IDAT;
   1254 
   1255          else
   1256             location = PNG_HAVE_IHDR; /* also undocumented */
   1257       }
   1258 
   1259       info_ptr->unknown_chunks[chunk].location =
   1260          check_location(png_ptr, location);
   1261    }
   1262 }
   1263 #endif /* STORE_UNKNOWN_CHUNKS */
   1264 
   1265 #ifdef PNG_MNG_FEATURES_SUPPORTED
   1266 png_uint_32 PNGAPI
   1267 png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
   1268 {
   1269    png_debug(1, "in png_permit_mng_features");
   1270 
   1271    if (png_ptr == NULL)
   1272       return 0;
   1273 
   1274    png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES;
   1275 
   1276    return png_ptr->mng_features_permitted;
   1277 }
   1278 #endif
   1279 
   1280 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
   1281 static unsigned int
   1282 add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
   1283 {
   1284    unsigned int i;
   1285 
   1286    /* Utility function: update the 'keep' state of a chunk if it is already in
   1287     * the list, otherwise add it to the list.
   1288     */
   1289    for (i=0; i<count; ++i, list += 5)
   1290    {
   1291       if (memcmp(list, add, 4) == 0)
   1292       {
   1293          list[4] = (png_byte)keep;
   1294 
   1295          return count;
   1296       }
   1297    }
   1298 
   1299    if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
   1300    {
   1301       ++count;
   1302       memcpy(list, add, 4);
   1303       list[4] = (png_byte)keep;
   1304    }
   1305 
   1306    return count;
   1307 }
   1308 
   1309 void PNGAPI
   1310 png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
   1311     png_const_bytep chunk_list, int num_chunks_in)
   1312 {
   1313    png_bytep new_list;
   1314    unsigned int num_chunks, old_num_chunks;
   1315 
   1316    if (png_ptr == NULL)
   1317       return;
   1318 
   1319    if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
   1320    {
   1321       png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");
   1322 
   1323       return;
   1324    }
   1325 
   1326    if (num_chunks_in <= 0)
   1327    {
   1328       png_ptr->unknown_default = keep;
   1329 
   1330       /* '0' means just set the flags, so stop here */
   1331       if (num_chunks_in == 0)
   1332         return;
   1333    }
   1334 
   1335    if (num_chunks_in < 0)
   1336    {
   1337       /* Ignore all unknown chunks and all chunks recognized by
   1338        * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
   1339        */
   1340       static PNG_CONST png_byte chunks_to_ignore[] = {
   1341          98,  75,  71,  68, '\0',  /* bKGD */
   1342          99,  72,  82,  77, '\0',  /* cHRM */
   1343         103,  65,  77,  65, '\0',  /* gAMA */
   1344         104,  73,  83,  84, '\0',  /* hIST */
   1345         105,  67,  67,  80, '\0',  /* iCCP */
   1346         105,  84,  88, 116, '\0',  /* iTXt */
   1347         111,  70,  70, 115, '\0',  /* oFFs */
   1348         112,  67,  65,  76, '\0',  /* pCAL */
   1349         112,  72,  89, 115, '\0',  /* pHYs */
   1350         115,  66,  73,  84, '\0',  /* sBIT */
   1351         115,  67,  65,  76, '\0',  /* sCAL */
   1352         115,  80,  76,  84, '\0',  /* sPLT */
   1353         115,  84,  69,  82, '\0',  /* sTER */
   1354         115,  82,  71,  66, '\0',  /* sRGB */
   1355         116,  69,  88, 116, '\0',  /* tEXt */
   1356         116,  73,  77,  69, '\0',  /* tIME */
   1357         122,  84,  88, 116, '\0'   /* zTXt */
   1358       };
   1359 
   1360       chunk_list = chunks_to_ignore;
   1361       num_chunks = (unsigned int)/*SAFE*/(sizeof chunks_to_ignore)/5U;
   1362    }
   1363 
   1364    else /* num_chunks_in > 0 */
   1365    {
   1366       if (chunk_list == NULL)
   1367       {
   1368          /* Prior to 1.6.0 this was silently ignored, now it is an app_error
   1369           * which can be switched off.
   1370           */
   1371          png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");
   1372 
   1373          return;
   1374       }
   1375 
   1376       num_chunks = num_chunks_in;
   1377    }
   1378 
   1379    old_num_chunks = png_ptr->num_chunk_list;
   1380    if (png_ptr->chunk_list == NULL)
   1381       old_num_chunks = 0;
   1382 
   1383    /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow.
   1384     */
   1385    if (num_chunks + old_num_chunks > UINT_MAX/5)
   1386    {
   1387       png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");
   1388 
   1389       return;
   1390    }
   1391 
   1392    /* If these chunks are being reset to the default then no more memory is
   1393     * required because add_one_chunk above doesn't extend the list if the 'keep'
   1394     * parameter is the default.
   1395     */
   1396    if (keep != 0)
   1397    {
   1398       new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
   1399           5 * (num_chunks + old_num_chunks)));
   1400 
   1401       if (old_num_chunks > 0)
   1402          memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks);
   1403    }
   1404 
   1405    else if (old_num_chunks > 0)
   1406       new_list = png_ptr->chunk_list;
   1407 
   1408    else
   1409       new_list = NULL;
   1410 
   1411    /* Add the new chunks together with each one's handling code.  If the chunk
   1412     * already exists the code is updated, otherwise the chunk is added to the
   1413     * end.  (In libpng 1.6.0 order no longer matters because this code enforces
   1414     * the earlier convention that the last setting is the one that is used.)
   1415     */
   1416    if (new_list != NULL)
   1417    {
   1418       png_const_bytep inlist;
   1419       png_bytep outlist;
   1420       unsigned int i;
   1421 
   1422       for (i=0; i<num_chunks; ++i)
   1423       {
   1424          old_num_chunks = add_one_chunk(new_list, old_num_chunks,
   1425              chunk_list+5*i, keep);
   1426       }
   1427 
   1428       /* Now remove any spurious 'default' entries. */
   1429       num_chunks = 0;
   1430       for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
   1431       {
   1432          if (inlist[4])
   1433          {
   1434             if (outlist != inlist)
   1435                memcpy(outlist, inlist, 5);
   1436             outlist += 5;
   1437             ++num_chunks;
   1438          }
   1439       }
   1440 
   1441       /* This means the application has removed all the specialized handling. */
   1442       if (num_chunks == 0)
   1443       {
   1444          if (png_ptr->chunk_list != new_list)
   1445             png_free(png_ptr, new_list);
   1446 
   1447          new_list = NULL;
   1448       }
   1449    }
   1450 
   1451    else
   1452       num_chunks = 0;
   1453 
   1454    png_ptr->num_chunk_list = num_chunks;
   1455 
   1456    if (png_ptr->chunk_list != new_list)
   1457    {
   1458       if (png_ptr->chunk_list != NULL)
   1459          png_free(png_ptr, png_ptr->chunk_list);
   1460 
   1461       png_ptr->chunk_list = new_list;
   1462    }
   1463 }
   1464 #endif
   1465 
   1466 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
   1467 void PNGAPI
   1468 png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr,
   1469     png_user_chunk_ptr read_user_chunk_fn)
   1470 {
   1471    png_debug(1, "in png_set_read_user_chunk_fn");
   1472 
   1473    if (png_ptr == NULL)
   1474       return;
   1475 
   1476    png_ptr->read_user_chunk_fn = read_user_chunk_fn;
   1477    png_ptr->user_chunk_ptr = user_chunk_ptr;
   1478 }
   1479 #endif
   1480 
   1481 #ifdef PNG_INFO_IMAGE_SUPPORTED
   1482 void PNGAPI
   1483 png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
   1484     png_bytepp row_pointers)
   1485 {
   1486    png_debug1(1, "in %s storage function", "rows");
   1487 
   1488    if (png_ptr == NULL || info_ptr == NULL)
   1489       return;
   1490 
   1491    if (info_ptr->row_pointers != NULL &&
   1492        (info_ptr->row_pointers != row_pointers))
   1493       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
   1494 
   1495    info_ptr->row_pointers = row_pointers;
   1496 
   1497    if (row_pointers != NULL)
   1498       info_ptr->valid |= PNG_INFO_IDAT;
   1499 }
   1500 #endif
   1501 
   1502 void PNGAPI
   1503 png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
   1504 {
   1505    if (png_ptr == NULL)
   1506       return;
   1507 
   1508    if (size == 0 || size > PNG_UINT_31_MAX)
   1509       png_error(png_ptr, "invalid compression buffer size");
   1510 
   1511 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
   1512    if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
   1513    {
   1514       png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
   1515       return;
   1516    }
   1517 #  endif
   1518 
   1519 #  ifdef PNG_WRITE_SUPPORTED
   1520    if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   1521    {
   1522       if (png_ptr->zowner != 0)
   1523       {
   1524          png_warning(png_ptr,
   1525              "Compression buffer size cannot be changed because it is in use");
   1526 
   1527          return;
   1528       }
   1529 
   1530 #ifndef __COVERITY__
   1531       /* Some compilers complain that this is always false.  However, it
   1532        * can be true when integer overflow happens.
   1533        */
   1534       if (size > ZLIB_IO_MAX)
   1535       {
   1536          png_warning(png_ptr,
   1537              "Compression buffer size limited to system maximum");
   1538          size = ZLIB_IO_MAX; /* must fit */
   1539       }
   1540 #endif
   1541 
   1542       if (size < 6)
   1543       {
   1544          /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
   1545           * if this is permitted.
   1546           */
   1547          png_warning(png_ptr,
   1548              "Compression buffer size cannot be reduced below 6");
   1549 
   1550          return;
   1551       }
   1552 
   1553       if (png_ptr->zbuffer_size != size)
   1554       {
   1555          png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
   1556          png_ptr->zbuffer_size = (uInt)size;
   1557       }
   1558    }
   1559 #  endif
   1560 }
   1561 
   1562 void PNGAPI
   1563 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
   1564 {
   1565    if (png_ptr != NULL && info_ptr != NULL)
   1566       info_ptr->valid &= ~mask;
   1567 }
   1568 
   1569 
   1570 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
   1571 /* This function was added to libpng 1.2.6 */
   1572 void PNGAPI
   1573 png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
   1574     png_uint_32 user_height_max)
   1575 {
   1576    /* Images with dimensions larger than these limits will be
   1577     * rejected by png_set_IHDR().  To accept any PNG datastream
   1578     * regardless of dimensions, set both limits to 0x7fffffff.
   1579     */
   1580    if (png_ptr == NULL)
   1581       return;
   1582 
   1583    png_ptr->user_width_max = user_width_max;
   1584    png_ptr->user_height_max = user_height_max;
   1585 }
   1586 
   1587 /* This function was added to libpng 1.4.0 */
   1588 void PNGAPI
   1589 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
   1590 {
   1591    if (png_ptr != NULL)
   1592       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
   1593 }
   1594 
   1595 /* This function was added to libpng 1.4.1 */
   1596 void PNGAPI
   1597 png_set_chunk_malloc_max (png_structrp png_ptr,
   1598     png_alloc_size_t user_chunk_malloc_max)
   1599 {
   1600    if (png_ptr != NULL)
   1601       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
   1602 }
   1603 #endif /* ?SET_USER_LIMITS */
   1604 
   1605 
   1606 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
   1607 void PNGAPI
   1608 png_set_benign_errors(png_structrp png_ptr, int allowed)
   1609 {
   1610    png_debug(1, "in png_set_benign_errors");
   1611 
   1612    /* If allowed is 1, png_benign_error() is treated as a warning.
   1613     *
   1614     * If allowed is 0, png_benign_error() is treated as an error (which
   1615     * is the default behavior if png_set_benign_errors() is not called).
   1616     */
   1617 
   1618    if (allowed != 0)
   1619       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
   1620          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;
   1621 
   1622    else
   1623       png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
   1624          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
   1625 }
   1626 #endif /* BENIGN_ERRORS */
   1627 
   1628 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
   1629    /* Whether to report invalid palette index; added at libng-1.5.10.
   1630     * It is possible for an indexed (color-type==3) PNG file to contain
   1631     * pixels with invalid (out-of-range) indexes if the PLTE chunk has
   1632     * fewer entries than the image's bit-depth would allow. We recover
   1633     * from this gracefully by filling any incomplete palette with zeros
   1634     * (opaque black).  By default, when this occurs libpng will issue
   1635     * a benign error.  This API can be used to override that behavior.
   1636     */
   1637 void PNGAPI
   1638 png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
   1639 {
   1640    png_debug(1, "in png_set_check_for_invalid_index");
   1641 
   1642    if (allowed > 0)
   1643       png_ptr->num_palette_max = 0;
   1644 
   1645    else
   1646       png_ptr->num_palette_max = -1;
   1647 }
   1648 #endif
   1649 
   1650 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) || \
   1651     defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
   1652 /* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification,
   1653  * and if invalid, correct the keyword rather than discarding the entire
   1654  * chunk.  The PNG 1.0 specification requires keywords 1-79 characters in
   1655  * length, forbids leading or trailing whitespace, multiple internal spaces,
   1656  * and the non-break space (0x80) from ISO 8859-1.  Returns keyword length.
   1657  *
   1658  * The 'new_key' buffer must be 80 characters in size (for the keyword plus a
   1659  * trailing '\0').  If this routine returns 0 then there was no keyword, or a
   1660  * valid one could not be generated, and the caller must png_error.
   1661  */
   1662 png_uint_32 /* PRIVATE */
   1663 png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
   1664 {
   1665 #ifdef PNG_WARNINGS_SUPPORTED
   1666    png_const_charp orig_key = key;
   1667 #endif
   1668    png_uint_32 key_len = 0;
   1669    int bad_character = 0;
   1670    int space = 1;
   1671 
   1672    png_debug(1, "in png_check_keyword");
   1673 
   1674    if (key == NULL)
   1675    {
   1676       *new_key = 0;
   1677       return 0;
   1678    }
   1679 
   1680    while (*key && key_len < 79)
   1681    {
   1682       png_byte ch = (png_byte)*key++;
   1683 
   1684       if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
   1685          *new_key++ = ch, ++key_len, space = 0;
   1686 
   1687       else if (space == 0)
   1688       {
   1689          /* A space or an invalid character when one wasn't seen immediately
   1690           * before; output just a space.
   1691           */
   1692          *new_key++ = 32, ++key_len, space = 1;
   1693 
   1694          /* If the character was not a space then it is invalid. */
   1695          if (ch != 32)
   1696             bad_character = ch;
   1697       }
   1698 
   1699       else if (bad_character == 0)
   1700          bad_character = ch; /* just skip it, record the first error */
   1701    }
   1702 
   1703    if (key_len > 0 && space != 0) /* trailing space */
   1704    {
   1705       --key_len, --new_key;
   1706       if (bad_character == 0)
   1707          bad_character = 32;
   1708    }
   1709 
   1710    /* Terminate the keyword */
   1711    *new_key = 0;
   1712 
   1713    if (key_len == 0)
   1714       return 0;
   1715 
   1716 #ifdef PNG_WARNINGS_SUPPORTED
   1717    /* Try to only output one warning per keyword: */
   1718    if (*key != 0) /* keyword too long */
   1719       png_warning(png_ptr, "keyword truncated");
   1720 
   1721    else if (bad_character != 0)
   1722    {
   1723       PNG_WARNING_PARAMETERS(p)
   1724 
   1725       png_warning_parameter(p, 1, orig_key);
   1726       png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character);
   1727 
   1728       png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
   1729    }
   1730 #else /* !WARNINGS */
   1731    PNG_UNUSED(png_ptr)
   1732 #endif /* !WARNINGS */
   1733 
   1734    return key_len;
   1735 }
   1736 #endif /* TEXT || pCAL || iCCP || sPLT */
   1737 #endif /* READ || WRITE */
   1738