2 /* pngset.c - storage of image information into info struct
4 * Last changed in libpng 1.6.0 [February 14, 2013]
5 * Copyright (c) 1998-2013 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.)
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
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.
21 #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
23 #ifdef PNG_bKGD_SUPPORTED
25 png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
26 png_const_color_16p background)
28 png_debug1(1, "in %s storage function", "bKGD");
30 if (png_ptr == NULL || info_ptr == NULL || background == NULL)
33 info_ptr->background = *background;
34 info_ptr->valid |= PNG_INFO_bKGD;
38 #ifdef PNG_cHRM_SUPPORTED
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)
47 png_debug1(1, "in %s storage function", "cHRM fixed");
49 if (png_ptr == NULL || info_ptr == NULL)
61 if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
62 2/* override with app values*/))
63 info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
65 png_colorspace_sync_info(png_ptr, info_ptr);
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)
78 png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
80 if (png_ptr == NULL || info_ptr == NULL)
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;
93 if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2))
94 info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
96 png_colorspace_sync_info(png_ptr, info_ptr);
99 # ifdef PNG_FLOATING_POINT_SUPPORTED
101 png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
102 double white_x, double white_y, double red_x, double red_y,
103 double green_x, double green_y, double blue_x, double blue_y)
105 png_set_cHRM_fixed(png_ptr, info_ptr,
106 png_fixed(png_ptr, white_x, "cHRM White X"),
107 png_fixed(png_ptr, white_y, "cHRM White Y"),
108 png_fixed(png_ptr, red_x, "cHRM Red X"),
109 png_fixed(png_ptr, red_y, "cHRM Red Y"),
110 png_fixed(png_ptr, green_x, "cHRM Green X"),
111 png_fixed(png_ptr, green_y, "cHRM Green Y"),
112 png_fixed(png_ptr, blue_x, "cHRM Blue X"),
113 png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
117 png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
118 double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
119 double blue_X, double blue_Y, double blue_Z)
121 png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
122 png_fixed(png_ptr, red_X, "cHRM Red X"),
123 png_fixed(png_ptr, red_Y, "cHRM Red Y"),
124 png_fixed(png_ptr, red_Z, "cHRM Red Z"),
125 png_fixed(png_ptr, green_X, "cHRM Red X"),
126 png_fixed(png_ptr, green_Y, "cHRM Red Y"),
127 png_fixed(png_ptr, green_Z, "cHRM Red Z"),
128 png_fixed(png_ptr, blue_X, "cHRM Red X"),
129 png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
130 png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
132 # endif /* PNG_FLOATING_POINT_SUPPORTED */
134 #endif /* PNG_cHRM_SUPPORTED */
136 #ifdef PNG_gAMA_SUPPORTED
138 png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
139 png_fixed_point file_gamma)
141 png_debug1(1, "in %s storage function", "gAMA");
143 if (png_ptr == NULL || info_ptr == NULL)
146 png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma);
147 png_colorspace_sync_info(png_ptr, info_ptr);
150 # ifdef PNG_FLOATING_POINT_SUPPORTED
152 png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma)
154 png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
160 #ifdef PNG_hIST_SUPPORTED
162 png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
163 png_const_uint_16p hist)
167 png_debug1(1, "in %s storage function", "hIST");
169 if (png_ptr == NULL || info_ptr == NULL)
172 if (info_ptr->num_palette == 0 || info_ptr->num_palette
173 > PNG_MAX_PALETTE_LENGTH)
176 "Invalid palette size, hIST allocation skipped");
181 png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
183 /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
186 info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr,
187 PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16))));
189 if (info_ptr->hist == NULL)
191 png_warning(png_ptr, "Insufficient memory for hIST chunk data");
195 info_ptr->free_me |= PNG_FREE_HIST;
197 for (i = 0; i < info_ptr->num_palette; i++)
198 info_ptr->hist[i] = hist[i];
200 info_ptr->valid |= PNG_INFO_hIST;
205 png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
206 png_uint_32 width, png_uint_32 height, int bit_depth,
207 int color_type, int interlace_type, int compression_type,
210 png_debug1(1, "in %s storage function", "IHDR");
212 if (png_ptr == NULL || info_ptr == NULL)
215 info_ptr->width = width;
216 info_ptr->height = height;
217 info_ptr->bit_depth = (png_byte)bit_depth;
218 info_ptr->color_type = (png_byte)color_type;
219 info_ptr->compression_type = (png_byte)compression_type;
220 info_ptr->filter_type = (png_byte)filter_type;
221 info_ptr->interlace_type = (png_byte)interlace_type;
223 png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
224 info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
225 info_ptr->compression_type, info_ptr->filter_type);
227 if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
228 info_ptr->channels = 1;
230 else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
231 info_ptr->channels = 3;
234 info_ptr->channels = 1;
236 if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
237 info_ptr->channels++;
239 info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
241 /* Check for potential overflow */
243 (PNG_UINT_32_MAX >> 3) /* 8-byte RRGGBBAA pixels */
244 - 48 /* bigrowbuf hack */
245 - 1 /* filter byte */
246 - 7*8 /* rounding of width to multiple of 8 pixels */
247 - 8) /* extra max_pixel_depth pad */
248 info_ptr->rowbytes = 0;
250 info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
253 #ifdef PNG_oFFs_SUPPORTED
255 png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr,
256 png_int_32 offset_x, png_int_32 offset_y, int unit_type)
258 png_debug1(1, "in %s storage function", "oFFs");
260 if (png_ptr == NULL || info_ptr == NULL)
263 info_ptr->x_offset = offset_x;
264 info_ptr->y_offset = offset_y;
265 info_ptr->offset_unit_type = (png_byte)unit_type;
266 info_ptr->valid |= PNG_INFO_oFFs;
270 #ifdef PNG_pCAL_SUPPORTED
272 png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
273 png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
274 int nparams, png_const_charp units, png_charpp params)
279 png_debug1(1, "in %s storage function", "pCAL");
281 if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
282 || (nparams > 0 && params == NULL))
285 length = strlen(purpose) + 1;
286 png_debug1(3, "allocating purpose for info (%lu bytes)",
287 (unsigned long)length);
289 /* TODO: validate format of calibration name and unit name */
291 /* Check that the type matches the specification. */
292 if (type < 0 || type > 3)
293 png_error(png_ptr, "Invalid pCAL equation type");
295 if (nparams < 0 || nparams > 255)
296 png_error(png_ptr, "Invalid pCAL parameter count");
298 /* Validate params[nparams] */
299 for (i=0; i<nparams; ++i)
300 if (params[i] == NULL ||
301 !png_check_fp_string(params[i], strlen(params[i])))
302 png_error(png_ptr, "Invalid format for pCAL parameter");
304 info_ptr->pcal_purpose = png_voidcast(png_charp,
305 png_malloc_warn(png_ptr, length));
307 if (info_ptr->pcal_purpose == NULL)
309 png_warning(png_ptr, "Insufficient memory for pCAL purpose");
313 memcpy(info_ptr->pcal_purpose, purpose, length);
315 png_debug(3, "storing X0, X1, type, and nparams in info");
316 info_ptr->pcal_X0 = X0;
317 info_ptr->pcal_X1 = X1;
318 info_ptr->pcal_type = (png_byte)type;
319 info_ptr->pcal_nparams = (png_byte)nparams;
321 length = strlen(units) + 1;
322 png_debug1(3, "allocating units for info (%lu bytes)",
323 (unsigned long)length);
325 info_ptr->pcal_units = png_voidcast(png_charp,
326 png_malloc_warn(png_ptr, length));
328 if (info_ptr->pcal_units == NULL)
330 png_warning(png_ptr, "Insufficient memory for pCAL units");
334 memcpy(info_ptr->pcal_units, units, length);
336 info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr,
337 (png_size_t)((nparams + 1) * (sizeof (png_charp)))));
339 if (info_ptr->pcal_params == NULL)
341 png_warning(png_ptr, "Insufficient memory for pCAL params");
345 memset(info_ptr->pcal_params, 0, (nparams + 1) * (sizeof (png_charp)));
347 for (i = 0; i < nparams; i++)
349 length = strlen(params[i]) + 1;
350 png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
351 (unsigned long)length);
353 info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
355 if (info_ptr->pcal_params[i] == NULL)
357 png_warning(png_ptr, "Insufficient memory for pCAL parameter");
361 memcpy(info_ptr->pcal_params[i], params[i], length);
364 info_ptr->valid |= PNG_INFO_pCAL;
365 info_ptr->free_me |= PNG_FREE_PCAL;
369 #ifdef PNG_sCAL_SUPPORTED
371 png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
372 int unit, png_const_charp swidth, png_const_charp sheight)
374 png_size_t lengthw = 0, lengthh = 0;
376 png_debug1(1, "in %s storage function", "sCAL");
378 if (png_ptr == NULL || info_ptr == NULL)
381 /* Double check the unit (should never get here with an invalid
382 * unit unless this is an API call.)
384 if (unit != 1 && unit != 2)
385 png_error(png_ptr, "Invalid sCAL unit");
387 if (swidth == NULL || (lengthw = strlen(swidth)) == 0 ||
388 swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
389 png_error(png_ptr, "Invalid sCAL width");
391 if (sheight == NULL || (lengthh = strlen(sheight)) == 0 ||
392 sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
393 png_error(png_ptr, "Invalid sCAL height");
395 info_ptr->scal_unit = (png_byte)unit;
399 png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
401 info_ptr->scal_s_width = png_voidcast(png_charp,
402 png_malloc_warn(png_ptr, lengthw));
404 if (info_ptr->scal_s_width == NULL)
406 png_warning(png_ptr, "Memory allocation failed while processing sCAL");
410 memcpy(info_ptr->scal_s_width, swidth, lengthw);
414 png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
416 info_ptr->scal_s_height = png_voidcast(png_charp,
417 png_malloc_warn(png_ptr, lengthh));
419 if (info_ptr->scal_s_height == NULL)
421 png_free (png_ptr, info_ptr->scal_s_width);
422 info_ptr->scal_s_width = NULL;
424 png_warning(png_ptr, "Memory allocation failed while processing sCAL");
428 memcpy(info_ptr->scal_s_height, sheight, lengthh);
430 info_ptr->valid |= PNG_INFO_sCAL;
431 info_ptr->free_me |= PNG_FREE_SCAL;
434 # ifdef PNG_FLOATING_POINT_SUPPORTED
436 png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
437 double width, double height)
439 png_debug1(1, "in %s storage function", "sCAL");
441 /* Check the arguments. */
443 png_warning(png_ptr, "Invalid sCAL width ignored");
445 else if (height <= 0)
446 png_warning(png_ptr, "Invalid sCAL height ignored");
450 /* Convert 'width' and 'height' to ASCII. */
451 char swidth[PNG_sCAL_MAX_DIGITS+1];
452 char sheight[PNG_sCAL_MAX_DIGITS+1];
454 png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width,
456 png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height,
459 png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
464 # ifdef PNG_FIXED_POINT_SUPPORTED
466 png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit,
467 png_fixed_point width, png_fixed_point height)
469 png_debug1(1, "in %s storage function", "sCAL");
471 /* Check the arguments. */
473 png_warning(png_ptr, "Invalid sCAL width ignored");
475 else if (height <= 0)
476 png_warning(png_ptr, "Invalid sCAL height ignored");
480 /* Convert 'width' and 'height' to ASCII. */
481 char swidth[PNG_sCAL_MAX_DIGITS+1];
482 char sheight[PNG_sCAL_MAX_DIGITS+1];
484 png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width);
485 png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height);
487 png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
493 #ifdef PNG_pHYs_SUPPORTED
495 png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr,
496 png_uint_32 res_x, png_uint_32 res_y, int unit_type)
498 png_debug1(1, "in %s storage function", "pHYs");
500 if (png_ptr == NULL || info_ptr == NULL)
503 info_ptr->x_pixels_per_unit = res_x;
504 info_ptr->y_pixels_per_unit = res_y;
505 info_ptr->phys_unit_type = (png_byte)unit_type;
506 info_ptr->valid |= PNG_INFO_pHYs;
511 png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
512 png_const_colorp palette, int num_palette)
515 png_debug1(1, "in %s storage function", "PLTE");
517 if (png_ptr == NULL || info_ptr == NULL || palette == NULL)
520 if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
522 if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
523 png_error(png_ptr, "Invalid palette length");
527 png_warning(png_ptr, "Invalid palette length");
532 /* It may not actually be necessary to set png_ptr->palette here;
533 * we do it for backward compatibility with the way the png_handle_tRNS
534 * function used to do the allocation.
536 * 1.6.0: the above statement appears to be incorrect; something has to set
537 * the palette inside png_struct on read.
539 png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
541 /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
542 * of num_palette entries, in case of an invalid PNG file that has
543 * too-large sample values.
545 png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr,
546 PNG_MAX_PALETTE_LENGTH * (sizeof (png_color))));
548 memcpy(png_ptr->palette, palette, num_palette * (sizeof (png_color)));
549 info_ptr->palette = png_ptr->palette;
550 info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
552 info_ptr->free_me |= PNG_FREE_PLTE;
554 info_ptr->valid |= PNG_INFO_PLTE;
557 #ifdef PNG_sBIT_SUPPORTED
559 png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
560 png_const_color_8p sig_bit)
562 png_debug1(1, "in %s storage function", "sBIT");
564 if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL)
567 info_ptr->sig_bit = *sig_bit;
568 info_ptr->valid |= PNG_INFO_sBIT;
572 #ifdef PNG_sRGB_SUPPORTED
574 png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent)
576 png_debug1(1, "in %s storage function", "sRGB");
578 if (png_ptr == NULL || info_ptr == NULL)
581 (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent);
582 png_colorspace_sync_info(png_ptr, info_ptr);
586 png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
589 png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
591 if (png_ptr == NULL || info_ptr == NULL)
594 if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent))
596 /* This causes the gAMA and cHRM to be written too */
597 info_ptr->colorspace.flags |=
598 PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
601 png_colorspace_sync_info(png_ptr, info_ptr);
606 #ifdef PNG_iCCP_SUPPORTED
608 png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
609 png_const_charp name, int compression_type,
610 png_const_bytep profile, png_uint_32 proflen)
612 png_charp new_iccp_name;
613 png_bytep new_iccp_profile;
616 png_debug1(1, "in %s storage function", "iCCP");
618 if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
621 if (compression_type != PNG_COMPRESSION_TYPE_BASE)
622 png_app_error(png_ptr, "Invalid iCCP compression method");
624 /* Set the colorspace first because this validates the profile; do not
625 * override previously set app cHRM or gAMA here (because likely as not the
626 * application knows better than libpng what the correct values are.) Pass
627 * the info_ptr color_type field to png_colorspace_set_ICC because in the
628 * write case it has not yet been stored in png_ptr.
631 int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name,
632 proflen, profile, info_ptr->color_type);
634 png_colorspace_sync_info(png_ptr, info_ptr);
636 /* Don't do any of the copying if the profile was bad, or inconsistent. */
640 /* But do write the gAMA and cHRM chunks from the profile. */
641 info_ptr->colorspace.flags |=
642 PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM;
645 length = strlen(name)+1;
646 new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length));
648 if (new_iccp_name == NULL)
650 png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
654 memcpy(new_iccp_name, name, length);
655 new_iccp_profile = png_voidcast(png_bytep,
656 png_malloc_warn(png_ptr, proflen));
658 if (new_iccp_profile == NULL)
660 png_free(png_ptr, new_iccp_name);
661 png_benign_error(png_ptr,
662 "Insufficient memory to process iCCP profile");
666 memcpy(new_iccp_profile, profile, proflen);
668 png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
670 info_ptr->iccp_proflen = proflen;
671 info_ptr->iccp_name = new_iccp_name;
672 info_ptr->iccp_profile = new_iccp_profile;
673 info_ptr->free_me |= PNG_FREE_ICCP;
674 info_ptr->valid |= PNG_INFO_iCCP;
678 #ifdef PNG_TEXT_SUPPORTED
680 png_set_text(png_const_structrp png_ptr, png_inforp info_ptr,
681 png_const_textp text_ptr, int num_text)
684 ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
687 png_error(png_ptr, "Insufficient memory to store text");
691 png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
692 png_const_textp text_ptr, int num_text)
696 png_debug1(1, "in %lx storage function", png_ptr == NULL ? "unexpected" :
697 (unsigned long)png_ptr->chunk_name);
699 if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL)
702 /* Make sure we have enough space in the "text" array in info_struct
703 * to hold all of the incoming text_ptr objects. This compare can't overflow
704 * because max_text >= num_text (anyway, subtract of two positive integers
705 * can't overflow in any case.)
707 if (num_text > info_ptr->max_text - info_ptr->num_text)
709 int old_num_text = info_ptr->num_text;
711 png_textp new_text = NULL;
713 /* Calculate an appropriate max_text, checking for overflow. */
714 max_text = old_num_text;
715 if (num_text <= INT_MAX - max_text)
717 max_text += num_text;
719 /* Round up to a multiple of 8 */
720 if (max_text < INT_MAX-8)
721 max_text = (max_text + 8) & ~0x7;
726 /* Now allocate a new array and copy the old members in, this does all
727 * the overflow checks.
729 new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
730 info_ptr->text, old_num_text, max_text-old_num_text,
734 if (new_text == NULL)
736 png_chunk_report(png_ptr, "too many text chunks",
737 PNG_CHUNK_WRITE_ERROR);
741 png_free(png_ptr, info_ptr->text);
743 info_ptr->text = new_text;
744 info_ptr->free_me |= PNG_FREE_TEXT;
745 info_ptr->max_text = max_text;
746 /* num_text is adjusted below as the entries are copied in */
748 png_debug1(3, "allocated %d entries for info_ptr->text", max_text);
751 for (i = 0; i < num_text; i++)
753 size_t text_length, key_len;
754 size_t lang_len, lang_key_len;
755 png_textp textp = &(info_ptr->text[info_ptr->num_text]);
757 if (text_ptr[i].key == NULL)
760 if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
761 text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
763 png_chunk_report(png_ptr, "text compression mode is out of range",
764 PNG_CHUNK_WRITE_ERROR);
768 key_len = strlen(text_ptr[i].key);
770 if (text_ptr[i].compression <= 0)
777 # ifdef PNG_iTXt_SUPPORTED
781 if (text_ptr[i].lang != NULL)
782 lang_len = strlen(text_ptr[i].lang);
787 if (text_ptr[i].lang_key != NULL)
788 lang_key_len = strlen(text_ptr[i].lang_key);
793 # else /* PNG_iTXt_SUPPORTED */
795 png_chunk_report(png_ptr, "iTXt chunk not supported",
796 PNG_CHUNK_WRITE_ERROR);
801 if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
804 # ifdef PNG_iTXt_SUPPORTED
805 if (text_ptr[i].compression > 0)
806 textp->compression = PNG_ITXT_COMPRESSION_NONE;
810 textp->compression = PNG_TEXT_COMPRESSION_NONE;
815 text_length = strlen(text_ptr[i].text);
816 textp->compression = text_ptr[i].compression;
819 textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr,
820 key_len + text_length + lang_len + lang_key_len + 4));
822 if (textp->key == NULL)
824 png_chunk_report(png_ptr, "text chunk: out of memory",
825 PNG_CHUNK_WRITE_ERROR);
829 png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
830 (unsigned long)(png_uint_32)
831 (key_len + lang_len + lang_key_len + text_length + 4),
834 memcpy(textp->key, text_ptr[i].key, key_len);
835 *(textp->key + key_len) = '\0';
837 if (text_ptr[i].compression > 0)
839 textp->lang = textp->key + key_len + 1;
840 memcpy(textp->lang, text_ptr[i].lang, lang_len);
841 *(textp->lang + lang_len) = '\0';
842 textp->lang_key = textp->lang + lang_len + 1;
843 memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
844 *(textp->lang_key + lang_key_len) = '\0';
845 textp->text = textp->lang_key + lang_key_len + 1;
851 textp->lang_key=NULL;
852 textp->text = textp->key + key_len + 1;
856 memcpy(textp->text, text_ptr[i].text, text_length);
858 *(textp->text + text_length) = '\0';
860 # ifdef PNG_iTXt_SUPPORTED
861 if (textp->compression > 0)
863 textp->text_length = 0;
864 textp->itxt_length = text_length;
870 textp->text_length = text_length;
871 textp->itxt_length = 0;
874 info_ptr->num_text++;
875 png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
882 #ifdef PNG_tIME_SUPPORTED
884 png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
885 png_const_timep mod_time)
887 png_debug1(1, "in %s storage function", "tIME");
889 if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
890 (png_ptr->mode & PNG_WROTE_tIME))
893 if (mod_time->month == 0 || mod_time->month > 12 ||
894 mod_time->day == 0 || mod_time->day > 31 ||
895 mod_time->hour > 23 || mod_time->minute > 59 ||
896 mod_time->second > 60)
898 png_warning(png_ptr, "Ignoring invalid time value");
902 info_ptr->mod_time = *mod_time;
903 info_ptr->valid |= PNG_INFO_tIME;
907 #ifdef PNG_tRNS_SUPPORTED
909 png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
910 png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
912 png_debug1(1, "in %s storage function", "tRNS");
914 if (png_ptr == NULL || info_ptr == NULL)
917 if (trans_alpha != NULL)
919 /* It may not actually be necessary to set png_ptr->trans_alpha here;
920 * we do it for backward compatibility with the way the png_handle_tRNS
921 * function used to do the allocation.
923 * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively
924 * relies on png_set_tRNS storing the information in png_struct
925 * (otherwise it won't be there for the code in pngrtran.c).
928 png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
930 /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
931 png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
932 png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
934 if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
935 memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
938 if (trans_color != NULL)
940 int sample_max = (1 << info_ptr->bit_depth);
942 if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
943 trans_color->gray > sample_max) ||
944 (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
945 (trans_color->red > sample_max ||
946 trans_color->green > sample_max ||
947 trans_color->blue > sample_max)))
949 "tRNS chunk has out-of-range samples for bit_depth");
951 info_ptr->trans_color = *trans_color;
957 info_ptr->num_trans = (png_uint_16)num_trans;
961 info_ptr->valid |= PNG_INFO_tRNS;
962 info_ptr->free_me |= PNG_FREE_TRNS;
967 #ifdef PNG_sPLT_SUPPORTED
969 png_set_sPLT(png_const_structrp png_ptr,
970 png_inforp info_ptr, png_const_sPLT_tp entries, int nentries)
972 * entries - array of png_sPLT_t structures
973 * to be added to the list of palettes
974 * in the info structure.
976 * nentries - number of palette structures to be
982 if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL)
985 /* Use the internal realloc function, which checks for all the possible
986 * overflows. Notice that the parameters are (int) and (size_t)
988 np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr,
989 info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries,
994 /* Out of memory or too many chunks */
995 png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
999 png_free(png_ptr, info_ptr->splt_palettes);
1000 info_ptr->splt_palettes = np;
1001 info_ptr->free_me |= PNG_FREE_SPLT;
1003 np += info_ptr->splt_palettes_num;
1009 /* Skip invalid input entries */
1010 if (entries->name == NULL || entries->entries == NULL)
1012 /* png_handle_sPLT doesn't do this, so this is an app error */
1013 png_app_error(png_ptr, "png_set_sPLT: invalid sPLT");
1014 /* Just skip the invalid entry */
1018 np->depth = entries->depth;
1020 /* In the even of out-of-memory just return - there's no point keeping on
1021 * trying to add sPLT chunks.
1023 length = strlen(entries->name) + 1;
1024 np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
1026 if (np->name == NULL)
1029 memcpy(np->name, entries->name, length);
1031 /* IMPORTANT: we have memory now that won't get freed if something else
1032 * goes wrong, this code must free it. png_malloc_array produces no
1033 * warnings, use a png_chunk_report (below) if there is an error.
1035 np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
1036 entries->nentries, sizeof (png_sPLT_entry)));
1038 if (np->entries == NULL)
1040 png_free(png_ptr, np->name);
1044 np->nentries = entries->nentries;
1045 /* This multiply can't overflow because png_malloc_array has already
1046 * checked it when doing the allocation.
1048 memcpy(np->entries, entries->entries,
1049 entries->nentries * sizeof (png_sPLT_entry));
1051 /* Note that 'continue' skips the advance of the out pointer and out
1052 * count, so an invalid entry is not added.
1054 info_ptr->valid |= PNG_INFO_sPLT;
1055 ++(info_ptr->splt_palettes_num);
1058 while (++entries, --nentries);
1061 png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
1063 #endif /* PNG_sPLT_SUPPORTED */
1065 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
1067 check_location(png_const_structrp png_ptr, int location)
1069 location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
1071 /* New in 1.6.0; copy the location and check it. This is an API
1072 * change, previously the app had to use the
1073 * png_set_unknown_chunk_location API below for each chunk.
1075 if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
1077 /* Write struct, so unknown chunks come from the app */
1078 png_app_warning(png_ptr,
1079 "png_set_unknown_chunks now expects a valid location");
1080 /* Use the old behavior */
1081 location = (png_byte)(png_ptr->mode &
1082 (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT));
1085 /* This need not be an internal error - if the app calls
1086 * png_set_unknown_chunks on a read pointer it must get the location right.
1089 png_error(png_ptr, "invalid location in png_set_unknown_chunks");
1091 /* Now reduce the location to the top-most set bit by removing each least
1092 * significant bit in turn.
1094 while (location != (location & -location))
1095 location &= ~(location & -location);
1097 /* The cast is safe because 'location' is a bit mask and only the low four
1098 * bits are significant.
1100 return (png_byte)location;
1104 png_set_unknown_chunks(png_const_structrp png_ptr,
1105 png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
1107 png_unknown_chunkp np;
1109 if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
1113 /* Check for the failure cases where support has been disabled at compile
1114 * time. This code is hardly ever compiled - it's here because
1115 * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this
1116 * code) but may be meaningless if the read or write handling of unknown
1117 * chunks is not compiled in.
1119 # if !(defined PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
1120 (defined PNG_READ_SUPPORTED)
1121 if (png_ptr->mode & PNG_IS_READ_STRUCT)
1123 png_app_error(png_ptr, "no unknown chunk support on read");
1127 # if !(defined PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
1128 (defined PNG_WRITE_SUPPORTED)
1129 if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
1131 png_app_error(png_ptr, "no unknown chunk support on write");
1136 /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that
1137 * unknown critical chunks could be lost with just a warning resulting in
1138 * undefined behavior. Now png_chunk_report is used to provide behavior
1139 * appropriate to read or write.
1141 np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr,
1142 info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns,
1147 png_chunk_report(png_ptr, "too many unknown chunks",
1148 PNG_CHUNK_WRITE_ERROR);
1152 png_free(png_ptr, info_ptr->unknown_chunks);
1153 info_ptr->unknown_chunks = np; /* safe because it is initialized */
1154 info_ptr->free_me |= PNG_FREE_UNKN;
1156 np += info_ptr->unknown_chunks_num;
1158 /* Increment unknown_chunks_num each time round the loop to protect the
1159 * just-allocated chunk data.
1161 for (; num_unknowns > 0; --num_unknowns, ++unknowns)
1163 memcpy(np->name, unknowns->name, (sizeof np->name));
1164 np->name[(sizeof np->name)-1] = '\0';
1165 np->location = check_location(png_ptr, unknowns->location);
1167 if (unknowns->size == 0)
1175 np->data = png_voidcast(png_bytep,
1176 png_malloc_base(png_ptr, unknowns->size));
1178 if (np->data == NULL)
1180 png_chunk_report(png_ptr, "unknown chunk: out of memory",
1181 PNG_CHUNK_WRITE_ERROR);
1182 /* But just skip storing the unknown chunk */
1186 memcpy(np->data, unknowns->data, unknowns->size);
1187 np->size = unknowns->size;
1190 /* These increments are skipped on out-of-memory for the data - the
1191 * unknown chunk entry gets overwritten if the png_chunk_report returns.
1192 * This is correct in the read case (the chunk is just dropped.)
1195 ++(info_ptr->unknown_chunks_num);
1200 png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
1201 int chunk, int location)
1203 /* This API is pretty pointless in 1.6.0 because the location can be set
1204 * before the call to png_set_unknown_chunks.
1206 * TODO: add a png_app_warning in 1.7
1208 if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
1209 chunk < info_ptr->unknown_chunks_num)
1211 if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0)
1213 png_app_error(png_ptr, "invalid unknown chunk location");
1214 /* Fake out the pre 1.6.0 behavior: */
1215 if ((location & PNG_HAVE_IDAT)) /* undocumented! */
1216 location = PNG_AFTER_IDAT;
1219 location = PNG_HAVE_IHDR; /* also undocumented */
1222 info_ptr->unknown_chunks[chunk].location =
1223 check_location(png_ptr, location);
1229 #ifdef PNG_MNG_FEATURES_SUPPORTED
1231 png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features)
1233 png_debug(1, "in png_permit_mng_features");
1235 if (png_ptr == NULL)
1238 png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES;
1240 return png_ptr->mng_features_permitted;
1244 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
1246 add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
1250 /* Utility function: update the 'keep' state of a chunk if it is already in
1251 * the list, otherwise add it to the list.
1253 for (i=0; i<count; ++i, list += 5) if (memcmp(list, add, 4) == 0)
1255 list[4] = (png_byte)keep;
1259 if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
1262 memcpy(list, add, 4);
1263 list[4] = (png_byte)keep;
1270 png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
1271 png_const_bytep chunk_list, int num_chunks_in)
1274 unsigned int num_chunks, old_num_chunks;
1276 if (png_ptr == NULL)
1279 if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
1281 png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");
1285 if (num_chunks_in <= 0)
1287 png_ptr->unknown_default = keep;
1289 /* '0' means just set the flags, so stop here */
1290 if (num_chunks_in == 0)
1294 if (num_chunks_in < 0)
1296 /* Ignore all unknown chunks and all chunks recognized by
1297 * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND
1299 static PNG_CONST png_byte chunks_to_ignore[] = {
1300 98, 75, 71, 68, '\0', /* bKGD */
1301 99, 72, 82, 77, '\0', /* cHRM */
1302 103, 65, 77, 65, '\0', /* gAMA */
1303 104, 73, 83, 84, '\0', /* hIST */
1304 105, 67, 67, 80, '\0', /* iCCP */
1305 105, 84, 88, 116, '\0', /* iTXt */
1306 111, 70, 70, 115, '\0', /* oFFs */
1307 112, 67, 65, 76, '\0', /* pCAL */
1308 112, 72, 89, 115, '\0', /* pHYs */
1309 115, 66, 73, 84, '\0', /* sBIT */
1310 115, 67, 65, 76, '\0', /* sCAL */
1311 115, 80, 76, 84, '\0', /* sPLT */
1312 115, 84, 69, 82, '\0', /* sTER */
1313 115, 82, 71, 66, '\0', /* sRGB */
1314 116, 69, 88, 116, '\0', /* tEXt */
1315 116, 73, 77, 69, '\0', /* tIME */
1316 122, 84, 88, 116, '\0' /* zTXt */
1319 chunk_list = chunks_to_ignore;
1320 num_chunks = (sizeof chunks_to_ignore)/5;
1323 else /* num_chunks_in > 0 */
1325 if (chunk_list == NULL)
1327 /* Prior to 1.6.0 this was silently ignored, now it is an app_error
1328 * which can be switched off.
1330 png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");
1334 num_chunks = num_chunks_in;
1337 old_num_chunks = png_ptr->num_chunk_list;
1338 if (png_ptr->chunk_list == NULL)
1341 /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow.
1343 if (num_chunks + old_num_chunks > UINT_MAX/5)
1345 png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");
1349 /* If these chunks are being reset to the default then no more memory is
1350 * required because add_one_chunk above doesn't extend the list if the 'keep'
1351 * parameter is the default.
1355 new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
1356 5 * (num_chunks + old_num_chunks)));
1358 if (old_num_chunks > 0)
1359 memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks);
1362 else if (old_num_chunks > 0)
1363 new_list = png_ptr->chunk_list;
1368 /* Add the new chunks together with each one's handling code. If the chunk
1369 * already exists the code is updated, otherwise the chunk is added to the
1370 * end. (In libpng 1.6.0 order no longer matters because this code enforces
1371 * the earlier convention that the last setting is the one that is used.)
1373 if (new_list != NULL)
1375 png_const_bytep inlist;
1379 for (i=0; i<num_chunks; ++i)
1380 old_num_chunks = add_one_chunk(new_list, old_num_chunks,
1381 chunk_list+5*i, keep);
1383 /* Now remove any spurious 'default' entries. */
1385 for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
1388 if (outlist != inlist)
1389 memcpy(outlist, inlist, 5);
1394 /* This means the application has removed all the specialized handling. */
1395 if (num_chunks == 0)
1397 if (png_ptr->chunk_list != new_list)
1398 png_free(png_ptr, new_list);
1407 png_ptr->num_chunk_list = num_chunks;
1409 if (png_ptr->chunk_list != new_list)
1411 if (png_ptr->chunk_list != NULL)
1412 png_free(png_ptr, png_ptr->chunk_list);
1414 png_ptr->chunk_list = new_list;
1419 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
1421 png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr,
1422 png_user_chunk_ptr read_user_chunk_fn)
1424 png_debug(1, "in png_set_read_user_chunk_fn");
1426 if (png_ptr == NULL)
1429 png_ptr->read_user_chunk_fn = read_user_chunk_fn;
1430 png_ptr->user_chunk_ptr = user_chunk_ptr;
1434 #ifdef PNG_INFO_IMAGE_SUPPORTED
1436 png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
1437 png_bytepp row_pointers)
1439 png_debug1(1, "in %s storage function", "rows");
1441 if (png_ptr == NULL || info_ptr == NULL)
1444 if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
1445 png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
1447 info_ptr->row_pointers = row_pointers;
1450 info_ptr->valid |= PNG_INFO_IDAT;
1455 png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
1457 if (png_ptr == NULL)
1460 if (size == 0 || size > PNG_UINT_31_MAX)
1461 png_error(png_ptr, "invalid compression buffer size");
1463 # ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1464 if (png_ptr->mode & PNG_IS_READ_STRUCT)
1466 png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
1471 # ifdef PNG_WRITE_SUPPORTED
1472 if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
1474 if (png_ptr->zowner != 0)
1476 png_warning(png_ptr,
1477 "Compression buffer size cannot be changed because it is in use");
1481 if (size > ZLIB_IO_MAX)
1483 png_warning(png_ptr,
1484 "Compression buffer size limited to system maximum");
1485 size = ZLIB_IO_MAX; /* must fit */
1490 /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
1491 * if this is permitted.
1493 png_warning(png_ptr,
1494 "Compression buffer size cannot be reduced below 6");
1498 if (png_ptr->zbuffer_size != size)
1500 png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
1501 png_ptr->zbuffer_size = (uInt)size;
1508 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
1510 if (png_ptr && info_ptr)
1511 info_ptr->valid &= ~mask;
1515 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
1516 /* This function was added to libpng 1.2.6 */
1518 png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
1519 png_uint_32 user_height_max)
1521 /* Images with dimensions larger than these limits will be
1522 * rejected by png_set_IHDR(). To accept any PNG datastream
1523 * regardless of dimensions, set both limits to 0x7ffffffL.
1525 if (png_ptr == NULL)
1528 png_ptr->user_width_max = user_width_max;
1529 png_ptr->user_height_max = user_height_max;
1532 /* This function was added to libpng 1.4.0 */
1534 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
1537 png_ptr->user_chunk_cache_max = user_chunk_cache_max;
1540 /* This function was added to libpng 1.4.1 */
1542 png_set_chunk_malloc_max (png_structrp png_ptr,
1543 png_alloc_size_t user_chunk_malloc_max)
1546 png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
1548 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
1551 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1553 png_set_benign_errors(png_structrp png_ptr, int allowed)
1555 png_debug(1, "in png_set_benign_errors");
1557 /* If allowed is 1, png_benign_error() is treated as a warning.
1559 * If allowed is 0, png_benign_error() is treated as an error (which
1560 * is the default behavior if png_set_benign_errors() is not called).
1564 png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
1565 PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;
1568 png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
1569 PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
1571 #endif /* PNG_BENIGN_ERRORS_SUPPORTED */
1573 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
1574 /* Whether to report invalid palette index; added at libng-1.5.10.
1575 * It is possible for an indexed (color-type==3) PNG file to contain
1576 * pixels with invalid (out-of-range) indexes if the PLTE chunk has
1577 * fewer entries than the image's bit-depth would allow. We recover
1578 * from this gracefully by filling any incomplete palette with zeroes
1579 * (opaque black). By default, when this occurs libpng will issue
1580 * a benign error. This API can be used to override that behavior.
1583 png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
1585 png_debug(1, "in png_set_check_for_invalid_index");
1588 png_ptr->num_palette_max = 0;
1591 png_ptr->num_palette_max = -1;
1594 #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */