pngpread.c
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1 
2 /* pngpread.c - read a png file in push mode
3  *
4  * Last changed in libpng 1.2.32 [September 18, 2008]
5  * For conditions of distribution and use, see copyright notice in png.h
6  * Copyright (c) 1998-2008 Glenn Randers-Pehrson
7  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
8  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
9  */
10 
11 #define PNG_INTERNAL
12 #include "png.h"
13 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
14 
15 /* push model modes */
16 #define PNG_READ_SIG_MODE 0
17 #define PNG_READ_CHUNK_MODE 1
18 #define PNG_READ_IDAT_MODE 2
19 #define PNG_SKIP_MODE 3
20 #define PNG_READ_tEXt_MODE 4
21 #define PNG_READ_zTXt_MODE 5
22 #define PNG_READ_DONE_MODE 6
23 #define PNG_READ_iTXt_MODE 7
24 #define PNG_ERROR_MODE 8
25 
26 void PNGAPI
29 {
30  if (png_ptr == NULL || info_ptr == NULL) return;
31  png_push_restore_buffer(png_ptr, buffer, buffer_size);
32 
33  while (png_ptr->buffer_size)
34  {
35  png_process_some_data(png_ptr, info_ptr);
36  }
37 }
38 
39 /* What we do with the incoming data depends on what we were previously
40  * doing before we ran out of data...
41  */
42 void /* PRIVATE */
44 {
45  if (png_ptr == NULL) return;
46  switch (png_ptr->process_mode)
47  {
48  case PNG_READ_SIG_MODE:
49  {
50  png_push_read_sig(png_ptr, info_ptr);
51  break;
52  }
54  {
55  png_push_read_chunk(png_ptr, info_ptr);
56  break;
57  }
58  case PNG_READ_IDAT_MODE:
59  {
60  png_push_read_IDAT(png_ptr);
61  break;
62  }
63 #if defined(PNG_READ_tEXt_SUPPORTED)
64  case PNG_READ_tEXt_MODE:
65  {
66  png_push_read_tEXt(png_ptr, info_ptr);
67  break;
68  }
69 #endif
70 #if defined(PNG_READ_zTXt_SUPPORTED)
71  case PNG_READ_zTXt_MODE:
72  {
73  png_push_read_zTXt(png_ptr, info_ptr);
74  break;
75  }
76 #endif
77 #if defined(PNG_READ_iTXt_SUPPORTED)
78  case PNG_READ_iTXt_MODE:
79  {
80  png_push_read_iTXt(png_ptr, info_ptr);
81  break;
82  }
83 #endif
84  case PNG_SKIP_MODE:
85  {
86  png_push_crc_finish(png_ptr);
87  break;
88  }
89  default:
90  {
91  png_ptr->buffer_size = 0;
92  break;
93  }
94  }
95 }
96 
97 /* Read any remaining signature bytes from the stream and compare them with
98  * the correct PNG signature. It is possible that this routine is called
99  * with bytes already read from the signature, either because they have been
100  * checked by the calling application, or because of multiple calls to this
101  * routine.
102  */
103 void /* PRIVATE */
105 {
106  png_size_t num_checked = png_ptr->sig_bytes,
107  num_to_check = 8 - num_checked;
108 
109  if (png_ptr->buffer_size < num_to_check)
110  {
111  num_to_check = png_ptr->buffer_size;
112  }
113 
114  png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
115  num_to_check);
116  png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes + num_to_check);
117 
118  if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
119  {
120  if (num_checked < 4 &&
121  png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
122  png_error(png_ptr, "Not a PNG file");
123  else
124  png_error(png_ptr, "PNG file corrupted by ASCII conversion");
125  }
126  else
127  {
128  if (png_ptr->sig_bytes >= 8)
129  {
130  png_ptr->process_mode = PNG_READ_CHUNK_MODE;
131  }
132  }
133 }
134 
135 void /* PRIVATE */
137 {
138 #ifdef PNG_USE_LOCAL_ARRAYS
143 #if defined(PNG_READ_bKGD_SUPPORTED)
145 #endif
146 #if defined(PNG_READ_cHRM_SUPPORTED)
148 #endif
149 #if defined(PNG_READ_gAMA_SUPPORTED)
151 #endif
152 #if defined(PNG_READ_hIST_SUPPORTED)
154 #endif
155 #if defined(PNG_READ_iCCP_SUPPORTED)
157 #endif
158 #if defined(PNG_READ_iTXt_SUPPORTED)
160 #endif
161 #if defined(PNG_READ_oFFs_SUPPORTED)
163 #endif
164 #if defined(PNG_READ_pCAL_SUPPORTED)
166 #endif
167 #if defined(PNG_READ_pHYs_SUPPORTED)
169 #endif
170 #if defined(PNG_READ_sBIT_SUPPORTED)
172 #endif
173 #if defined(PNG_READ_sCAL_SUPPORTED)
175 #endif
176 #if defined(PNG_READ_sRGB_SUPPORTED)
178 #endif
179 #if defined(PNG_READ_sPLT_SUPPORTED)
181 #endif
182 #if defined(PNG_READ_tEXt_SUPPORTED)
184 #endif
185 #if defined(PNG_READ_tIME_SUPPORTED)
187 #endif
188 #if defined(PNG_READ_tRNS_SUPPORTED)
190 #endif
191 #if defined(PNG_READ_zTXt_SUPPORTED)
193 #endif
194 #endif /* PNG_USE_LOCAL_ARRAYS */
195  /* First we make sure we have enough data for the 4 byte chunk name
196  * and the 4 byte chunk length before proceeding with decoding the
197  * chunk data. To fully decode each of these chunks, we also make
198  * sure we have enough data in the buffer for the 4 byte CRC at the
199  * end of every chunk (except IDAT, which is handled separately).
200  */
201  if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
202  {
203  png_byte chunk_length[4];
204 
205  if (png_ptr->buffer_size < 8)
206  {
207  png_push_save_buffer(png_ptr);
208  return;
209  }
210 
211  png_push_fill_buffer(png_ptr, chunk_length, 4);
212  png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
213  png_reset_crc(png_ptr);
214  png_crc_read(png_ptr, png_ptr->chunk_name, 4);
215  png_check_chunk_name(png_ptr, png_ptr->chunk_name);
216  png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
217  }
218 
219  if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
220  if (png_ptr->mode & PNG_AFTER_IDAT)
221  png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
222 
223  if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
224  {
225  if (png_ptr->push_length != 13)
226  png_error(png_ptr, "Invalid IHDR length");
227  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
228  {
229  png_push_save_buffer(png_ptr);
230  return;
231  }
232  png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
233  }
234  else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
235  {
236  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
237  {
238  png_push_save_buffer(png_ptr);
239  return;
240  }
241  png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
242 
243  png_ptr->process_mode = PNG_READ_DONE_MODE;
244  png_push_have_end(png_ptr, info_ptr);
245  }
246 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
247  else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
248  {
249  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
250  {
251  png_push_save_buffer(png_ptr);
252  return;
253  }
254  if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
255  png_ptr->mode |= PNG_HAVE_IDAT;
256  png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
257  if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
258  png_ptr->mode |= PNG_HAVE_PLTE;
259  else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
260  {
261  if (!(png_ptr->mode & PNG_HAVE_IHDR))
262  png_error(png_ptr, "Missing IHDR before IDAT");
263  else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
264  !(png_ptr->mode & PNG_HAVE_PLTE))
265  png_error(png_ptr, "Missing PLTE before IDAT");
266  }
267  }
268 #endif
269  else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
270  {
271  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
272  {
273  png_push_save_buffer(png_ptr);
274  return;
275  }
276  png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
277  }
278  else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
279  {
280  /* If we reach an IDAT chunk, this means we have read all of the
281  * header chunks, and we can start reading the image (or if this
282  * is called after the image has been read - we have an error).
283  */
284  if (!(png_ptr->mode & PNG_HAVE_IHDR))
285  png_error(png_ptr, "Missing IHDR before IDAT");
286  else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
287  !(png_ptr->mode & PNG_HAVE_PLTE))
288  png_error(png_ptr, "Missing PLTE before IDAT");
289 
290  if (png_ptr->mode & PNG_HAVE_IDAT)
291  {
292  if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
293  if (png_ptr->push_length == 0)
294  return;
295 
296  if (png_ptr->mode & PNG_AFTER_IDAT)
297  png_error(png_ptr, "Too many IDAT's found");
298  }
299 
300  png_ptr->idat_size = png_ptr->push_length;
301  png_ptr->mode |= PNG_HAVE_IDAT;
302  png_ptr->process_mode = PNG_READ_IDAT_MODE;
303  png_push_have_info(png_ptr, info_ptr);
304  png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
305  png_ptr->zstream.next_out = png_ptr->row_buf;
306  return;
307  }
308 #if defined(PNG_READ_gAMA_SUPPORTED)
309  else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
310  {
311  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
312  {
313  png_push_save_buffer(png_ptr);
314  return;
315  }
316  png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
317  }
318 #endif
319 #if defined(PNG_READ_sBIT_SUPPORTED)
320  else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
321  {
322  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
323  {
324  png_push_save_buffer(png_ptr);
325  return;
326  }
327  png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
328  }
329 #endif
330 #if defined(PNG_READ_cHRM_SUPPORTED)
331  else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
332  {
333  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
334  {
335  png_push_save_buffer(png_ptr);
336  return;
337  }
338  png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
339  }
340 #endif
341 #if defined(PNG_READ_sRGB_SUPPORTED)
342  else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
343  {
344  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
345  {
346  png_push_save_buffer(png_ptr);
347  return;
348  }
349  png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
350  }
351 #endif
352 #if defined(PNG_READ_iCCP_SUPPORTED)
353  else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
354  {
355  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
356  {
357  png_push_save_buffer(png_ptr);
358  return;
359  }
360  png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
361  }
362 #endif
363 #if defined(PNG_READ_sPLT_SUPPORTED)
364  else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
365  {
366  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
367  {
368  png_push_save_buffer(png_ptr);
369  return;
370  }
371  png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
372  }
373 #endif
374 #if defined(PNG_READ_tRNS_SUPPORTED)
375  else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
376  {
377  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
378  {
379  png_push_save_buffer(png_ptr);
380  return;
381  }
382  png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
383  }
384 #endif
385 #if defined(PNG_READ_bKGD_SUPPORTED)
386  else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
387  {
388  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
389  {
390  png_push_save_buffer(png_ptr);
391  return;
392  }
393  png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
394  }
395 #endif
396 #if defined(PNG_READ_hIST_SUPPORTED)
397  else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
398  {
399  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
400  {
401  png_push_save_buffer(png_ptr);
402  return;
403  }
404  png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
405  }
406 #endif
407 #if defined(PNG_READ_pHYs_SUPPORTED)
408  else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
409  {
410  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
411  {
412  png_push_save_buffer(png_ptr);
413  return;
414  }
415  png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
416  }
417 #endif
418 #if defined(PNG_READ_oFFs_SUPPORTED)
419  else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
420  {
421  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
422  {
423  png_push_save_buffer(png_ptr);
424  return;
425  }
426  png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
427  }
428 #endif
429 #if defined(PNG_READ_pCAL_SUPPORTED)
430  else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
431  {
432  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
433  {
434  png_push_save_buffer(png_ptr);
435  return;
436  }
437  png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
438  }
439 #endif
440 #if defined(PNG_READ_sCAL_SUPPORTED)
441  else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
442  {
443  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
444  {
445  png_push_save_buffer(png_ptr);
446  return;
447  }
448  png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
449  }
450 #endif
451 #if defined(PNG_READ_tIME_SUPPORTED)
452  else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
453  {
454  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
455  {
456  png_push_save_buffer(png_ptr);
457  return;
458  }
459  png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
460  }
461 #endif
462 #if defined(PNG_READ_tEXt_SUPPORTED)
463  else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
464  {
465  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
466  {
467  png_push_save_buffer(png_ptr);
468  return;
469  }
470  png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
471  }
472 #endif
473 #if defined(PNG_READ_zTXt_SUPPORTED)
474  else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
475  {
476  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
477  {
478  png_push_save_buffer(png_ptr);
479  return;
480  }
481  png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
482  }
483 #endif
484 #if defined(PNG_READ_iTXt_SUPPORTED)
485  else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
486  {
487  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
488  {
489  png_push_save_buffer(png_ptr);
490  return;
491  }
492  png_push_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
493  }
494 #endif
495  else
496  {
497  if (png_ptr->push_length + 4 > png_ptr->buffer_size)
498  {
499  png_push_save_buffer(png_ptr);
500  return;
501  }
502  png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
503  }
504 
505  png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
506 }
507 
508 void /* PRIVATE */
510 {
511  png_ptr->process_mode = PNG_SKIP_MODE;
512  png_ptr->skip_length = skip;
513 }
514 
515 void /* PRIVATE */
517 {
518  if (png_ptr->skip_length && png_ptr->save_buffer_size)
519  {
520  png_size_t save_size;
521 
522  if (png_ptr->skip_length < (png_uint_32)png_ptr->save_buffer_size)
523  save_size = (png_size_t)png_ptr->skip_length;
524  else
525  save_size = png_ptr->save_buffer_size;
526 
527  png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
528 
529  png_ptr->skip_length -= save_size;
530  png_ptr->buffer_size -= save_size;
531  png_ptr->save_buffer_size -= save_size;
532  png_ptr->save_buffer_ptr += save_size;
533  }
534  if (png_ptr->skip_length && png_ptr->current_buffer_size)
535  {
536  png_size_t save_size;
537 
538  if (png_ptr->skip_length < (png_uint_32)png_ptr->current_buffer_size)
539  save_size = (png_size_t)png_ptr->skip_length;
540  else
541  save_size = png_ptr->current_buffer_size;
542 
543  png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
544 
545  png_ptr->skip_length -= save_size;
546  png_ptr->buffer_size -= save_size;
547  png_ptr->current_buffer_size -= save_size;
548  png_ptr->current_buffer_ptr += save_size;
549  }
550  if (!png_ptr->skip_length)
551  {
552  if (png_ptr->buffer_size < 4)
553  {
554  png_push_save_buffer(png_ptr);
555  return;
556  }
557 
558  png_crc_finish(png_ptr, 0);
559  png_ptr->process_mode = PNG_READ_CHUNK_MODE;
560  }
561 }
562 
563 void PNGAPI
565 {
566  png_bytep ptr;
567 
568  if (png_ptr == NULL) return;
569  ptr = buffer;
570  if (png_ptr->save_buffer_size)
571  {
572  png_size_t save_size;
573 
574  if (length < png_ptr->save_buffer_size)
575  save_size = length;
576  else
577  save_size = png_ptr->save_buffer_size;
578 
579  png_memcpy(ptr, png_ptr->save_buffer_ptr, save_size);
580  length -= save_size;
581  ptr += save_size;
582  png_ptr->buffer_size -= save_size;
583  png_ptr->save_buffer_size -= save_size;
584  png_ptr->save_buffer_ptr += save_size;
585  }
586  if (length && png_ptr->current_buffer_size)
587  {
588  png_size_t save_size;
589 
590  if (length < png_ptr->current_buffer_size)
591  save_size = length;
592  else
593  save_size = png_ptr->current_buffer_size;
594 
595  png_memcpy(ptr, png_ptr->current_buffer_ptr, save_size);
596  png_ptr->buffer_size -= save_size;
597  png_ptr->current_buffer_size -= save_size;
598  png_ptr->current_buffer_ptr += save_size;
599  }
600 }
601 
602 void /* PRIVATE */
604 {
605  if (png_ptr->save_buffer_size)
606  {
607  if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
608  {
609  png_size_t i, istop;
610  png_bytep sp;
611  png_bytep dp;
612 
613  istop = png_ptr->save_buffer_size;
614  for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
615  i < istop; i++, sp++, dp++)
616  {
617  *dp = *sp;
618  }
619  }
620  }
621  if (png_ptr->save_buffer_size + png_ptr->current_buffer_size >
622  png_ptr->save_buffer_max)
623  {
624  png_size_t new_max;
625  png_bytep old_buffer;
626 
627  if (png_ptr->save_buffer_size > PNG_SIZE_MAX -
628  (png_ptr->current_buffer_size + 256))
629  {
630  png_error(png_ptr, "Potential overflow of save_buffer");
631  }
632  new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
633  old_buffer = png_ptr->save_buffer;
634  png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr,
635  (png_uint_32)new_max);
636  png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
637  png_free(png_ptr, old_buffer);
638  png_ptr->save_buffer_max = new_max;
639  }
640  if (png_ptr->current_buffer_size)
641  {
642  png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size,
643  png_ptr->current_buffer_ptr, png_ptr->current_buffer_size);
644  png_ptr->save_buffer_size += png_ptr->current_buffer_size;
645  png_ptr->current_buffer_size = 0;
646  }
647  png_ptr->save_buffer_ptr = png_ptr->save_buffer;
648  png_ptr->buffer_size = 0;
649 }
650 
651 void /* PRIVATE */
653  png_size_t buffer_length)
654 {
655  png_ptr->current_buffer = buffer;
656  png_ptr->current_buffer_size = buffer_length;
657  png_ptr->buffer_size = buffer_length + png_ptr->save_buffer_size;
658  png_ptr->current_buffer_ptr = png_ptr->current_buffer;
659 }
660 
661 void /* PRIVATE */
663 {
664 #ifdef PNG_USE_LOCAL_ARRAYS
666 #endif
667  if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
668  {
669  png_byte chunk_length[4];
670 
671  if (png_ptr->buffer_size < 8)
672  {
673  png_push_save_buffer(png_ptr);
674  return;
675  }
676 
677  png_push_fill_buffer(png_ptr, chunk_length, 4);
678  png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
679  png_reset_crc(png_ptr);
680  png_crc_read(png_ptr, png_ptr->chunk_name, 4);
681  png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
682 
683  if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
684  {
685  png_ptr->process_mode = PNG_READ_CHUNK_MODE;
686  if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
687  png_error(png_ptr, "Not enough compressed data");
688  return;
689  }
690 
691  png_ptr->idat_size = png_ptr->push_length;
692  }
693  if (png_ptr->idat_size && png_ptr->save_buffer_size)
694  {
695  png_size_t save_size;
696 
697  if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
698  {
699  save_size = (png_size_t)png_ptr->idat_size;
700  /* check for overflow */
701  if ((png_uint_32)save_size != png_ptr->idat_size)
702  png_error(png_ptr, "save_size overflowed in pngpread");
703  }
704  else
705  save_size = png_ptr->save_buffer_size;
706 
707  png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
708  if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
709  png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
710  png_ptr->idat_size -= save_size;
711  png_ptr->buffer_size -= save_size;
712  png_ptr->save_buffer_size -= save_size;
713  png_ptr->save_buffer_ptr += save_size;
714  }
715  if (png_ptr->idat_size && png_ptr->current_buffer_size)
716  {
717  png_size_t save_size;
718 
719  if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
720  {
721  save_size = (png_size_t)png_ptr->idat_size;
722  /* check for overflow */
723  if ((png_uint_32)save_size != png_ptr->idat_size)
724  png_error(png_ptr, "save_size overflowed in pngpread");
725  }
726  else
727  save_size = png_ptr->current_buffer_size;
728 
729  png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
730  if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
731  png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
732 
733  png_ptr->idat_size -= save_size;
734  png_ptr->buffer_size -= save_size;
735  png_ptr->current_buffer_size -= save_size;
736  png_ptr->current_buffer_ptr += save_size;
737  }
738  if (!png_ptr->idat_size)
739  {
740  if (png_ptr->buffer_size < 4)
741  {
742  png_push_save_buffer(png_ptr);
743  return;
744  }
745 
746  png_crc_finish(png_ptr, 0);
747  png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
748  png_ptr->mode |= PNG_AFTER_IDAT;
749  }
750 }
751 
752 void /* PRIVATE */
754  png_size_t buffer_length)
755 {
756  int ret;
757 
758  if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length)
759  png_error(png_ptr, "Extra compression data");
760 
761  png_ptr->zstream.next_in = buffer;
762  png_ptr->zstream.avail_in = (uInt)buffer_length;
763  for (;;)
764  {
765  ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
766  if (ret != Z_OK)
767  {
768  if (ret == Z_STREAM_END)
769  {
770  if (png_ptr->zstream.avail_in)
771  png_error(png_ptr, "Extra compressed data");
772  if (!(png_ptr->zstream.avail_out))
773  {
774  png_push_process_row(png_ptr);
775  }
776 
777  png_ptr->mode |= PNG_AFTER_IDAT;
778  png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
779  break;
780  }
781  else if (ret == Z_BUF_ERROR)
782  break;
783  else
784  png_error(png_ptr, "Decompression Error");
785  }
786  if (!(png_ptr->zstream.avail_out))
787  {
788  if ((
790  png_ptr->interlaced && png_ptr->pass > 6) ||
791  (!png_ptr->interlaced &&
792 #endif
793  png_ptr->row_number == png_ptr->num_rows))
794  {
795  if (png_ptr->zstream.avail_in)
796  png_warning(png_ptr, "Too much data in IDAT chunks");
797  png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
798  break;
799  }
800  png_push_process_row(png_ptr);
801  png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
802  png_ptr->zstream.next_out = png_ptr->row_buf;
803  }
804  else
805  break;
806  }
807 }
808 
809 void /* PRIVATE */
811 {
812  png_ptr->row_info.color_type = png_ptr->color_type;
813  png_ptr->row_info.width = png_ptr->iwidth;
814  png_ptr->row_info.channels = png_ptr->channels;
815  png_ptr->row_info.bit_depth = png_ptr->bit_depth;
816  png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
817 
818  png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
819  png_ptr->row_info.width);
820 
821  png_read_filter_row(png_ptr, &(png_ptr->row_info),
822  png_ptr->row_buf + 1, png_ptr->prev_row + 1,
823  (int)(png_ptr->row_buf[0]));
824 
825  png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
826  png_ptr->rowbytes + 1);
827 
828  if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
830 
831 #if defined(PNG_READ_INTERLACING_SUPPORTED)
832  /* blow up interlaced rows to full size */
833  if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
834  {
835  if (png_ptr->pass < 6)
836 /* old interface (pre-1.0.9):
837  png_do_read_interlace(&(png_ptr->row_info),
838  png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
839  */
840  png_do_read_interlace(png_ptr);
841 
842  switch (png_ptr->pass)
843  {
844  case 0:
845  {
846  int i;
847  for (i = 0; i < 8 && png_ptr->pass == 0; i++)
848  {
849  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
850  png_read_push_finish_row(png_ptr); /* updates png_ptr->pass */
851  }
852  if (png_ptr->pass == 2) /* pass 1 might be empty */
853  {
854  for (i = 0; i < 4 && png_ptr->pass == 2; i++)
855  {
857  png_read_push_finish_row(png_ptr);
858  }
859  }
860  if (png_ptr->pass == 4 && png_ptr->height <= 4)
861  {
862  for (i = 0; i < 2 && png_ptr->pass == 4; i++)
863  {
865  png_read_push_finish_row(png_ptr);
866  }
867  }
868  if (png_ptr->pass == 6 && png_ptr->height <= 4)
869  {
871  png_read_push_finish_row(png_ptr);
872  }
873  break;
874  }
875  case 1:
876  {
877  int i;
878  for (i = 0; i < 8 && png_ptr->pass == 1; i++)
879  {
880  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
881  png_read_push_finish_row(png_ptr);
882  }
883  if (png_ptr->pass == 2) /* skip top 4 generated rows */
884  {
885  for (i = 0; i < 4 && png_ptr->pass == 2; i++)
886  {
888  png_read_push_finish_row(png_ptr);
889  }
890  }
891  break;
892  }
893  case 2:
894  {
895  int i;
896  for (i = 0; i < 4 && png_ptr->pass == 2; i++)
897  {
898  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
899  png_read_push_finish_row(png_ptr);
900  }
901  for (i = 0; i < 4 && png_ptr->pass == 2; i++)
902  {
904  png_read_push_finish_row(png_ptr);
905  }
906  if (png_ptr->pass == 4) /* pass 3 might be empty */
907  {
908  for (i = 0; i < 2 && png_ptr->pass == 4; i++)
909  {
911  png_read_push_finish_row(png_ptr);
912  }
913  }
914  break;
915  }
916  case 3:
917  {
918  int i;
919  for (i = 0; i < 4 && png_ptr->pass == 3; i++)
920  {
921  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
922  png_read_push_finish_row(png_ptr);
923  }
924  if (png_ptr->pass == 4) /* skip top two generated rows */
925  {
926  for (i = 0; i < 2 && png_ptr->pass == 4; i++)
927  {
929  png_read_push_finish_row(png_ptr);
930  }
931  }
932  break;
933  }
934  case 4:
935  {
936  int i;
937  for (i = 0; i < 2 && png_ptr->pass == 4; i++)
938  {
939  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
940  png_read_push_finish_row(png_ptr);
941  }
942  for (i = 0; i < 2 && png_ptr->pass == 4; i++)
943  {
945  png_read_push_finish_row(png_ptr);
946  }
947  if (png_ptr->pass == 6) /* pass 5 might be empty */
948  {
950  png_read_push_finish_row(png_ptr);
951  }
952  break;
953  }
954  case 5:
955  {
956  int i;
957  for (i = 0; i < 2 && png_ptr->pass == 5; i++)
958  {
959  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
960  png_read_push_finish_row(png_ptr);
961  }
962  if (png_ptr->pass == 6) /* skip top generated row */
963  {
965  png_read_push_finish_row(png_ptr);
966  }
967  break;
968  }
969  case 6:
970  {
971  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
972  png_read_push_finish_row(png_ptr);
973  if (png_ptr->pass != 6)
974  break;
976  png_read_push_finish_row(png_ptr);
977  }
978  }
979  }
980  else
981 #endif
982  {
983  png_push_have_row(png_ptr, png_ptr->row_buf + 1);
984  png_read_push_finish_row(png_ptr);
985  }
986 }
987 
988 void /* PRIVATE */
990 {
991 #ifdef PNG_USE_LOCAL_ARRAYS
992  /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
993 
994  /* start of interlace block */
995  PNG_CONST int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
996 
997  /* offset to next interlace block */
998  PNG_CONST int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
999 
1000  /* start of interlace block in the y direction */
1001  PNG_CONST int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
1002 
1003  /* offset to next interlace block in the y direction */
1004  PNG_CONST int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
1005 
1006  /* Height of interlace block. This is not currently used - if you need
1007  * it, uncomment it here and in png.h
1008  PNG_CONST int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
1009  */
1010 #endif
1011 
1012  png_ptr->row_number++;
1013  if (png_ptr->row_number < png_ptr->num_rows)
1014  return;
1015 
1016  if (png_ptr->interlaced)
1017  {
1018  png_ptr->row_number = 0;
1019  png_memset_check(png_ptr, png_ptr->prev_row, 0,
1020  png_ptr->rowbytes + 1);
1021  do
1022  {
1023  png_ptr->pass++;
1024  if ((png_ptr->pass == 1 && png_ptr->width < 5) ||
1025  (png_ptr->pass == 3 && png_ptr->width < 3) ||
1026  (png_ptr->pass == 5 && png_ptr->width < 2))
1027  png_ptr->pass++;
1028 
1029  if (png_ptr->pass > 7)
1030  png_ptr->pass--;
1031  if (png_ptr->pass >= 7)
1032  break;
1033 
1034  png_ptr->iwidth = (png_ptr->width +
1035  png_pass_inc[png_ptr->pass] - 1 -
1036  png_pass_start[png_ptr->pass]) /
1037  png_pass_inc[png_ptr->pass];
1038 
1039  png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,
1040  png_ptr->iwidth) + 1;
1041 
1042  if (png_ptr->transformations & PNG_INTERLACE)
1043  break;
1044 
1045  png_ptr->num_rows = (png_ptr->height +
1046  png_pass_yinc[png_ptr->pass] - 1 -
1047  png_pass_ystart[png_ptr->pass]) /
1048  png_pass_yinc[png_ptr->pass];
1049 
1050  } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
1051  }
1052 }
1053 
1054 #if defined(PNG_READ_tEXt_SUPPORTED)
1055 void /* PRIVATE */
1057  length)
1058 {
1059  if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
1060  {
1061  png_error(png_ptr, "Out of place tEXt");
1062  info_ptr = info_ptr; /* to quiet some compiler warnings */
1063  }
1064 
1065 #ifdef PNG_MAX_MALLOC_64K
1066  png_ptr->skip_length = 0; /* This may not be necessary */
1067 
1068  if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
1069  {
1070  png_warning(png_ptr, "tEXt chunk too large to fit in memory");
1071  png_ptr->skip_length = length - (png_uint_32)65535L;
1072  length = (png_uint_32)65535L;
1073  }
1074 #endif
1075 
1076  png_ptr->current_text = (png_charp)png_malloc(png_ptr,
1077  (png_uint_32)(length + 1));
1078  png_ptr->current_text[length] = '\0';
1079  png_ptr->current_text_ptr = png_ptr->current_text;
1080  png_ptr->current_text_size = (png_size_t)length;
1081  png_ptr->current_text_left = (png_size_t)length;
1082  png_ptr->process_mode = PNG_READ_tEXt_MODE;
1083 }
1084 
1085 void /* PRIVATE */
1087 {
1088  if (png_ptr->buffer_size && png_ptr->current_text_left)
1089  {
1090  png_size_t text_size;
1091 
1092  if (png_ptr->buffer_size < png_ptr->current_text_left)
1093  text_size = png_ptr->buffer_size;
1094  else
1095  text_size = png_ptr->current_text_left;
1096  png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
1097  png_ptr->current_text_left -= text_size;
1098  png_ptr->current_text_ptr += text_size;
1099  }
1100  if (!(png_ptr->current_text_left))
1101  {
1103  png_charp text;
1104  png_charp key;
1105  int ret;
1106 
1107  if (png_ptr->buffer_size < 4)
1108  {
1109  png_push_save_buffer(png_ptr);
1110  return;
1111  }
1112 
1113  png_push_crc_finish(png_ptr);
1114 
1115 #if defined(PNG_MAX_MALLOC_64K)
1116  if (png_ptr->skip_length)
1117  return;
1118 #endif
1119 
1120  key = png_ptr->current_text;
1121 
1122  for (text = key; *text; text++)
1123  /* empty loop */ ;
1124 
1125  if (text < key + png_ptr->current_text_size)
1126  text++;
1127 
1128  text_ptr = (png_textp)png_malloc(png_ptr,
1130  text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
1131  text_ptr->key = key;
1132 #ifdef PNG_iTXt_SUPPORTED
1133  text_ptr->lang = NULL;
1134  text_ptr->lang_key = NULL;
1135 #endif
1136  text_ptr->text = text;
1137 
1138  ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
1139 
1140  png_free(png_ptr, key);
1141  png_free(png_ptr, text_ptr);
1142  png_ptr->current_text = NULL;
1143 
1144  if (ret)
1145  png_warning(png_ptr, "Insufficient memory to store text chunk.");
1146  }
1147 }
1148 #endif
1149 
1150 #if defined(PNG_READ_zTXt_SUPPORTED)
1151 void /* PRIVATE */
1153  length)
1154 {
1155  if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
1156  {
1157  png_error(png_ptr, "Out of place zTXt");
1158  info_ptr = info_ptr; /* to quiet some compiler warnings */
1159  }
1160 
1161 #ifdef PNG_MAX_MALLOC_64K
1162  /* We can't handle zTXt chunks > 64K, since we don't have enough space
1163  * to be able to store the uncompressed data. Actually, the threshold
1164  * is probably around 32K, but it isn't as definite as 64K is.
1165  */
1166  if (length > (png_uint_32)65535L)
1167  {
1168  png_warning(png_ptr, "zTXt chunk too large to fit in memory");
1169  png_push_crc_skip(png_ptr, length);
1170  return;
1171  }
1172 #endif
1173 
1174  png_ptr->current_text = (png_charp)png_malloc(png_ptr,
1175  (png_uint_32)(length + 1));
1176  png_ptr->current_text[length] = '\0';
1177  png_ptr->current_text_ptr = png_ptr->current_text;
1178  png_ptr->current_text_size = (png_size_t)length;
1179  png_ptr->current_text_left = (png_size_t)length;
1180  png_ptr->process_mode = PNG_READ_zTXt_MODE;
1181 }
1182 
1183 void /* PRIVATE */
1185 {
1186  if (png_ptr->buffer_size && png_ptr->current_text_left)
1187  {
1188  png_size_t text_size;
1189 
1190  if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
1191  text_size = png_ptr->buffer_size;
1192  else
1193  text_size = png_ptr->current_text_left;
1194  png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
1195  png_ptr->current_text_left -= text_size;
1196  png_ptr->current_text_ptr += text_size;
1197  }
1198  if (!(png_ptr->current_text_left))
1199  {
1201  png_charp text;
1202  png_charp key;
1203  int ret;
1204  png_size_t text_size, key_size;
1205 
1206  if (png_ptr->buffer_size < 4)
1207  {
1208  png_push_save_buffer(png_ptr);
1209  return;
1210  }
1211 
1212  png_push_crc_finish(png_ptr);
1213 
1214  key = png_ptr->current_text;
1215 
1216  for (text = key; *text; text++)
1217  /* empty loop */ ;
1218 
1219  /* zTXt can't have zero text */
1220  if (text >= key + png_ptr->current_text_size)
1221  {
1222  png_ptr->current_text = NULL;
1223  png_free(png_ptr, key);
1224  return;
1225  }
1226 
1227  text++;
1228 
1229  if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
1230  {
1231  png_ptr->current_text = NULL;
1232  png_free(png_ptr, key);
1233  return;
1234  }
1235 
1236  text++;
1237 
1238  png_ptr->zstream.next_in = (png_bytep )text;
1239  png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
1240  (text - key));
1241  png_ptr->zstream.next_out = png_ptr->zbuf;
1242  png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
1243 
1244  key_size = text - key;
1245  text_size = 0;
1246  text = NULL;
1247  ret = Z_STREAM_END;
1248 
1249  while (png_ptr->zstream.avail_in)
1250  {
1251  ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
1252  if (ret != Z_OK && ret != Z_STREAM_END)
1253  {
1254  inflateReset(&png_ptr->zstream);
1255  png_ptr->zstream.avail_in = 0;
1256  png_ptr->current_text = NULL;
1257  png_free(png_ptr, key);
1258  png_free(png_ptr, text);
1259  return;
1260  }
1261  if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
1262  {
1263  if (text == NULL)
1264  {
1265  text = (png_charp)png_malloc(png_ptr,
1266  (png_uint_32)(png_ptr->zbuf_size
1267  - png_ptr->zstream.avail_out + key_size + 1));
1268  png_memcpy(text + key_size, png_ptr->zbuf,
1269  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
1270  png_memcpy(text, key, key_size);
1271  text_size = key_size + png_ptr->zbuf_size -
1272  png_ptr->zstream.avail_out;
1273  *(text + text_size) = '\0';
1274  }
1275  else
1276  {
1277  png_charp tmp;
1278 
1279  tmp = text;
1280  text = (png_charp)png_malloc(png_ptr, text_size +
1281  (png_uint_32)(png_ptr->zbuf_size
1282  - png_ptr->zstream.avail_out + 1));
1283  png_memcpy(text, tmp, text_size);
1284  png_free(png_ptr, tmp);
1285  png_memcpy(text + text_size, png_ptr->zbuf,
1286  png_ptr->zbuf_size - png_ptr->zstream.avail_out);
1287  text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
1288  *(text + text_size) = '\0';
1289  }
1290  if (ret != Z_STREAM_END)
1291  {
1292  png_ptr->zstream.next_out = png_ptr->zbuf;
1293  png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
1294  }
1295  }
1296  else
1297  {
1298  break;
1299  }
1300 
1301  if (ret == Z_STREAM_END)
1302  break;
1303  }
1304 
1305  inflateReset(&png_ptr->zstream);
1306  png_ptr->zstream.avail_in = 0;
1307 
1308  if (ret != Z_STREAM_END)
1309  {
1310  png_ptr->current_text = NULL;
1311  png_free(png_ptr, key);
1312  png_free(png_ptr, text);
1313  return;
1314  }
1315 
1316  png_ptr->current_text = NULL;
1317  png_free(png_ptr, key);
1318  key = text;
1319  text += key_size;
1320 
1321  text_ptr = (png_textp)png_malloc(png_ptr,
1323  text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
1324  text_ptr->key = key;
1325 #ifdef PNG_iTXt_SUPPORTED
1326  text_ptr->lang = NULL;
1327  text_ptr->lang_key = NULL;
1328 #endif
1329  text_ptr->text = text;
1330 
1331  ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
1332 
1333  png_free(png_ptr, key);
1334  png_free(png_ptr, text_ptr);
1335 
1336  if (ret)
1337  png_warning(png_ptr, "Insufficient memory to store text chunk.");
1338  }
1339 }
1340 #endif
1341 
1342 #if defined(PNG_READ_iTXt_SUPPORTED)
1343 void /* PRIVATE */
1344 png_push_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32
1345  length)
1346 {
1347  if (!(png_ptr->mode & PNG_HAVE_IHDR) || (png_ptr->mode & PNG_HAVE_IEND))
1348  {
1349  png_error(png_ptr, "Out of place iTXt");
1350  info_ptr = info_ptr; /* to quiet some compiler warnings */
1351  }
1352 
1353 #ifdef PNG_MAX_MALLOC_64K
1354  png_ptr->skip_length = 0; /* This may not be necessary */
1355 
1356  if (length > (png_uint_32)65535L) /* Can't hold entire string in memory */
1357  {
1358  png_warning(png_ptr, "iTXt chunk too large to fit in memory");
1359  png_ptr->skip_length = length - (png_uint_32)65535L;
1360  length = (png_uint_32)65535L;
1361  }
1362 #endif
1363 
1364  png_ptr->current_text = (png_charp)png_malloc(png_ptr,
1365  (png_uint_32)(length + 1));
1366  png_ptr->current_text[length] = '\0';
1367  png_ptr->current_text_ptr = png_ptr->current_text;
1368  png_ptr->current_text_size = (png_size_t)length;
1369  png_ptr->current_text_left = (png_size_t)length;
1370  png_ptr->process_mode = PNG_READ_iTXt_MODE;
1371 }
1372 
1373 void /* PRIVATE */
1374 png_push_read_iTXt(png_structp png_ptr, png_infop info_ptr)
1375 {
1376 
1377  if (png_ptr->buffer_size && png_ptr->current_text_left)
1378  {
1379  png_size_t text_size;
1380 
1381  if (png_ptr->buffer_size < png_ptr->current_text_left)
1382  text_size = png_ptr->buffer_size;
1383  else
1384  text_size = png_ptr->current_text_left;
1385  png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
1386  png_ptr->current_text_left -= text_size;
1387  png_ptr->current_text_ptr += text_size;
1388  }
1389  if (!(png_ptr->current_text_left))
1390  {
1392  png_charp key;
1393  int comp_flag;
1394  png_charp lang;
1395  png_charp lang_key;
1396  png_charp text;
1397  int ret;
1398 
1399  if (png_ptr->buffer_size < 4)
1400  {
1401  png_push_save_buffer(png_ptr);
1402  return;
1403  }
1404 
1405  png_push_crc_finish(png_ptr);
1406 
1407 #if defined(PNG_MAX_MALLOC_64K)
1408  if (png_ptr->skip_length)
1409  return;
1410 #endif
1411 
1412  key = png_ptr->current_text;
1413 
1414  for (lang = key; *lang; lang++)
1415  /* empty loop */ ;
1416 
1417  if (lang < key + png_ptr->current_text_size - 3)
1418  lang++;
1419 
1420  comp_flag = *lang++;
1421  lang++; /* skip comp_type, always zero */
1422 
1423  for (lang_key = lang; *lang_key; lang_key++)
1424  /* empty loop */ ;
1425  lang_key++; /* skip NUL separator */
1426 
1427  text=lang_key;
1428  if (lang_key < key + png_ptr->current_text_size - 1)
1429  {
1430  for (; *text; text++)
1431  /* empty loop */ ;
1432  }
1433 
1434  if (text < key + png_ptr->current_text_size)
1435  text++;
1436 
1437  text_ptr = (png_textp)png_malloc(png_ptr,
1439  text_ptr->compression = comp_flag + 2;
1440  text_ptr->key = key;
1441  text_ptr->lang = lang;
1442  text_ptr->lang_key = lang_key;
1443  text_ptr->text = text;
1444  text_ptr->text_length = 0;
1445  text_ptr->itxt_length = png_strlen(text);
1446 
1447  ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
1448 
1449  png_ptr->current_text = NULL;
1450 
1451  png_free(png_ptr, text_ptr);
1452  if (ret)
1453  png_warning(png_ptr, "Insufficient memory to store iTXt chunk.");
1454  }
1455 }
1456 #endif
1457 
1458 /* This function is called when we haven't found a handler for this
1459  * chunk. If there isn't a problem with the chunk itself (ie a bad chunk
1460  * name or a critical chunk), the chunk is (currently) silently ignored.
1461  */
1462 void /* PRIVATE */
1464  length)
1465 {
1466  png_uint_32 skip = 0;
1467 
1468  if (!(png_ptr->chunk_name[0] & 0x20))
1469  {
1470 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
1471  if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
1473 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
1474  && png_ptr->read_user_chunk_fn == NULL
1475 #endif
1476  )
1477 #endif
1478  png_chunk_error(png_ptr, "unknown critical chunk");
1479 
1480  info_ptr = info_ptr; /* to quiet some compiler warnings */
1481  }
1482 
1483 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
1484  if (png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
1485  {
1486 #ifdef PNG_MAX_MALLOC_64K
1487  if (length > (png_uint_32)65535L)
1488  {
1489  png_warning(png_ptr, "unknown chunk too large to fit in memory");
1490  skip = length - (png_uint_32)65535L;
1491  length = (png_uint_32)65535L;
1492  }
1493 #endif
1494  png_memcpy((png_charp)png_ptr->unknown_chunk.name,
1495  (png_charp)png_ptr->chunk_name,
1496  png_sizeof(png_ptr->unknown_chunk.name));
1497  png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name) - 1]
1498  = '\0';
1499 
1500  png_ptr->unknown_chunk.size = (png_size_t)length;
1501  if (length == 0)
1502  png_ptr->unknown_chunk.data = NULL;
1503  else
1504  {
1505  png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr,
1506  (png_uint_32)length);
1507  png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
1508  }
1509 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
1510  if (png_ptr->read_user_chunk_fn != NULL)
1511  {
1512  /* callback to user unknown chunk handler */
1513  int ret;
1514  ret = (*(png_ptr->read_user_chunk_fn))
1515  (png_ptr, &png_ptr->unknown_chunk);
1516  if (ret < 0)
1517  png_chunk_error(png_ptr, "error in user chunk");
1518  if (ret == 0)
1519  {
1520  if (!(png_ptr->chunk_name[0] & 0x20))
1521  if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
1523  png_chunk_error(png_ptr, "unknown critical chunk");
1524  png_set_unknown_chunks(png_ptr, info_ptr,
1525  &png_ptr->unknown_chunk, 1);
1526  }
1527  }
1528  else
1529 #endif
1530  png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
1531  png_free(png_ptr, png_ptr->unknown_chunk.data);
1532  png_ptr->unknown_chunk.data = NULL;
1533  }
1534  else
1535 #endif
1536  skip=length;
1537  png_push_crc_skip(png_ptr, skip);
1538 }
1539 
1540 void /* PRIVATE */
1542 {
1543  if (png_ptr->info_fn != NULL)
1544  (*(png_ptr->info_fn))(png_ptr, info_ptr);
1545 }
1546 
1547 void /* PRIVATE */
1549 {
1550  if (png_ptr->end_fn != NULL)
1551  (*(png_ptr->end_fn))(png_ptr, info_ptr);
1552 }
1553 
1554 void /* PRIVATE */
1556 {
1557  if (png_ptr->row_fn != NULL)
1558  (*(png_ptr->row_fn))(png_ptr, row, png_ptr->row_number,
1559  (int)png_ptr->pass);
1560 }
1561 
1562 void PNGAPI
1565 {
1566 #ifdef PNG_USE_LOCAL_ARRAYS
1568  {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
1569 #endif
1570  if (png_ptr == NULL) return;
1571  if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */
1572  png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
1573 }
1574 
1575 void PNGAPI
1577  png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
1578  png_progressive_end_ptr end_fn)
1579 {
1580  if (png_ptr == NULL) return;
1581  png_ptr->info_fn = info_fn;
1582  png_ptr->row_fn = row_fn;
1583  png_ptr->end_fn = end_fn;
1584 
1585  png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
1586 }
1587 
1590 {
1591  if (png_ptr == NULL) return (NULL);
1592  return png_ptr->io_ptr;
1593 }
1594 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
void png_push_read_IDAT(png_structp png_ptr)
Definition: pngpread.c:662
#define PNG_READ_INTERLACING_SUPPORTED
Definition: pngconf.h:613
PNG_tRNS
Definition: png.c:52
PNG_CONST int FARDATA png_pass_start[]
Definition: png.c:59
png_bytep png_bytep new_row
Definition: png.h:2048
void png_push_have_row(png_structp png_ptr, png_bytep row)
Definition: pngpread.c:1555
void png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:597
PNG_PLTE
Definition: png.c:36
#define PNG_READ_DONE_MODE
Definition: pngpread.c:22
int ZEXPORT inflateReset(z_streamp strm)
Definition: inflate.c:103
PNG_sRGB
Definition: png.c:49
void PNGAPI png_process_data(png_structp png_ptr, png_infop info_ptr, png_bytep buffer, png_size_t buffer_size)
Definition: pngpread.c:27
#define png_strlen
Definition: pngconf.h:1463
png_infop png_textp * text_ptr
Definition: png.h:2407
void png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:104
void png_push_have_end(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:1548
png_voidp ptr
Definition: png.h:2063
PNG_sPLT
Definition: png.c:48
#define Z_PARTIAL_FLUSH
Definition: zlib.h:163
png_voidp progressive_ptr
Definition: png.h:2032
#define png_memcmp
Definition: pngconf.h:1464
void PNGAPI png_set_unknown_chunks(png_structp png_ptr, png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
Definition: pngset.c:1048
png_byte FAR * png_bytep
Definition: pngconf.h:1197
char FAR * png_charp
Definition: pngconf.h:1203
#define PNG_COLOR_TYPE_PALETTE
Definition: png.h:1004
void png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:388
PNG_CONST int FARDATA png_pass_yinc[]
Definition: png.c:68
void png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1128
png_size_t png_size_t num_to_check
Definition: png.h:1496
void PNGAPI png_progressive_combine_row(png_structp png_ptr, png_bytep old_row, png_bytep new_row)
Definition: pngpread.c:1563
RTC::ReturnCode_t ret(RTC::Local::ReturnCode_t r)
png_voidp png_progressive_info_ptr png_progressive_row_ptr row_fn
Definition: png.h:2032
PNG_bKGD
Definition: png.c:37
#define PNG_HAVE_PLTE
Definition: png.h:2760
void png_do_read_transformations(png_structp png_ptr)
Definition: pngrtran.c:1269
int PNGAPI png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name)
Definition: png.c:742
PNG_sCAL
Definition: png.c:45
PNG_cHRM
Definition: png.c:38
void png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
Definition: pngrutil.c:133
PNG_CONST int FARDATA png_pass_ystart[]
Definition: png.c:65
png_voidp png_progressive_info_ptr info_fn
Definition: png.h:2032
void png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1731
png_bytep png_bytep png_size_t length
Definition: png.h:1541
png_uint_32 i
Definition: png.h:2735
png_text FAR * png_textp
Definition: png.h:654
png_voidp PNGAPI png_get_progressive_ptr(png_structp png_ptr)
Definition: pngpread.c:1589
#define PNG_READ_IDAT_MODE
Definition: pngpread.c:18
void png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:136
PNG_zTXt
Definition: png.c:53
#define PNG_READ_zTXt_MODE
Definition: pngpread.c:21
void png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length)
Definition: png.c:212
#define PNG_TEXT_COMPRESSION_zTXt
Definition: png.h:663
PNG_IDAT
Definition: png.c:34
void png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:766
#define PNG_HAVE_IHDR
Definition: png.h:2759
void png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1456
void png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngpread.c:1152
void png_push_save_buffer(png_structp png_ptr)
Definition: pngpread.c:603
#define PNG_TEXT_COMPRESSION_NONE
Definition: png.h:662
#define PNGAPI
Definition: pngconf.h:1386
png_struct FAR * png_structp
Definition: png.h:1108
#define PNG_HANDLE_CHUNK_ALWAYS
Definition: png.h:2579
#define PNG_SKIP_MODE
Definition: pngpread.c:19
PNG_pHYs
Definition: png.c:46
PNG_tEXt
Definition: png.c:50
void PNGAPI png_error(png_structp png_ptr, png_const_charp error_message)
Definition: pngerror.c:36
#define PNG_CONST
Definition: pngconf.h:445
PNG_sBIT
Definition: png.c:47
void png_push_crc_finish(png_structp png_ptr)
Definition: pngpread.c:516
PNG_IHDR
Definition: png.c:33
unsigned char png_byte
Definition: pngconf.h:1120
#define PNG_READ_iTXt_MODE
Definition: pngpread.c:23
#define png_memcpy
Definition: pngconf.h:1465
void png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1597
void png_do_read_interlace(png_structp png_ptr)
Definition: pngrutil.c:2554
#define PNG_SIZE_MAX
Definition: png.h:990
void PNGAPI png_warning(png_structp png_ptr, png_const_charp warning_message)
Definition: pngerror.c:102
void png_combine_row(png_structp png_ptr, png_bytep row, int mask)
Definition: pngrutil.c:2348
PNG_CONST int FARDATA png_pass_dsp_mask[]
Definition: png.c:80
#define Z_STREAM_END
Definition: zlib.h:171
PNG_IEND
Definition: png.c:35
png_bytepp row
Definition: png.h:1759
void png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngpread.c:1056
void png_push_crc_skip(png_structp png_ptr, png_uint_32 skip)
Definition: pngpread.c:509
#define PNG_READ_USER_CHUNKS_SUPPORTED
Definition: pngconf.h:939
void png_process_IDAT_data(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length)
Definition: pngpread.c:753
void png_read_push_finish_row(png_structp png_ptr)
Definition: pngpread.c:989
png_voidp png_progressive_info_ptr png_progressive_row_ptr png_progressive_end_ptr end_fn
Definition: png.h:2032
void png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:2229
int PNGAPI png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
Definition: png.c:112
#define PNG_HAVE_IDAT
Definition: png.h:2761
#define PNG_READ_CHUNK_MODE
Definition: pngpread.c:17
#define PNG_AFTER_IDAT
Definition: png.h:2762
int png_crc_finish(png_structp png_ptr, png_uint_32 skip)
Definition: pngrutil.c:145
PNG_tIME
Definition: png.c:51
PNG_gAMA
Definition: png.c:39
void PNGAPI png_chunk_error(png_structp png_ptr, png_const_charp error_message)
Definition: pngerror.c:178
void PNGAPI png_set_read_fn(png_structp png_ptr, png_voidp io_ptr, png_rw_ptr read_data_fn)
Definition: pngrio.c:137
int png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr, int num_text)
Definition: pngset.c:741
#define FARDATA
Definition: pngconf.h:1188
png_uint_32 PNGAPI png_get_uint_31(png_structp png_ptr, png_bytep buf)
Definition: pngrutil.c:49
png_bytep old_row
Definition: png.h:2048
void png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1272
void png_push_restore_buffer(png_structp png_ptr, png_bytep buffer, png_size_t buffer_length)
Definition: pngpread.c:652
void png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:911
PNG_hIST
Definition: png.c:40
PNG_iTXt
Definition: png.c:42
#define PNG_READ_tEXt_MODE
Definition: pngpread.c:20
typedef int
Definition: png.h:1113
PNG_CONST int FARDATA png_pass_inc[]
Definition: png.c:62
void png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row, png_bytep prev_row, int filter)
Definition: pngrutil.c:2776
#define png_bytep_NULL
Definition: png.h:501
png_voidp PNGAPI png_memcpy_check(png_structp png_ptr, png_voidp s1, png_voidp s2, png_uint_32 length)
Definition: pngmem.c:556
png_infop png_bytep png_size_t buffer_size
Definition: png.h:2042
png_infop png_bytep buffer
Definition: png.h:2042
void png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1873
void png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1553
#define Z_BUF_ERROR
Definition: zlib.h:177
void png_process_some_data(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:43
void FAR * png_voidp
Definition: pngconf.h:1196
void PNGAPI png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
Definition: pngpread.c:564
void png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1367
png_voidp PNGAPI png_memset_check(png_structp png_ptr, png_voidp s1, int value, png_uint_32 length)
Definition: pngmem.c:569
#define Z_OK
Definition: zlib.h:170
void png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:619
size_t png_size_t
Definition: pngconf.h:1128
PNG_pCAL
Definition: png.c:44
void png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:700
void png_push_process_row(png_structp png_ptr)
Definition: pngpread.c:810
int ZEXPORT inflate(z_streamp strm, int flush)
Definition: inflate.c:554
void png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngpread.c:1463
void png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1009
void PNGAPI png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr, png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn, png_progressive_end_ptr end_fn)
Definition: pngpread.c:1576
png_infop info_ptr
Definition: png.h:1571
unsigned long png_uint_32
Definition: pngconf.h:1116
PNG_iCCP
Definition: png.c:41
#define PNG_READ_SIG_MODE
Definition: pngpread.c:16
void png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:459
void PNGAPI png_free(png_structp png_ptr, png_voidp ptr)
Definition: pngmem.c:498
void png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:1086
void png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:1184
void png_push_have_info(png_structp png_ptr, png_infop info_ptr)
Definition: pngpread.c:1541
void png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
Definition: pngrutil.c:1510
void png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)
Definition: pngrutil.c:2326
png_voidp PNGAPI png_malloc(png_structp png_ptr, png_uint_32 size)
Definition: pngmem.c:429
void png_reset_crc(png_structp png_ptr)
Definition: png.c:201
PNG_oFFs
Definition: png.c:43
unsigned int uInt
Definition: zconf.h:263
#define PNG_HAVE_IEND
Definition: png.h:2763
#define png_sizeof(x)
Definition: pngconf.h:1129
png_info FAR * png_infop
Definition: png.h:984


openhrp3
Author(s): AIST, General Robotix Inc., Nakamura Lab of Dept. of Mechano Informatics at University of Tokyo
autogenerated on Thu Sep 8 2022 02:24:05