1
2/* pngread.c - read a PNG file
3 *
4 * Last changed in libpng 1.2.24 December 14, 2007
5 * For conditions of distribution and use, see copyright notice in png.h
6 * Copyright (c) 1998-2007 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 * This file contains routines that an application calls directly to
11 * read a PNG file or stream.
12 */
13
14#define PNG_INTERNAL
15#include "png.h"
16
17#if defined(PNG_READ_SUPPORTED)
18
19/* Create a PNG structure for reading, and allocate any memory needed. */
20png_structp PNGAPI
21png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr,
22 png_error_ptr error_fn, png_error_ptr warn_fn)
23{
24
25#ifdef PNG_USER_MEM_SUPPORTED
26 return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn,
27 warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL));
28}
29
30/* Alternate create PNG structure for reading, and allocate any memory needed. */
31png_structp PNGAPI
32png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr,
33 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr,
34 png_malloc_ptr malloc_fn, png_free_ptr free_fn)
35{
36#endif /* PNG_USER_MEM_SUPPORTED */
37
38 png_structp png_ptr;
39
40#ifdef PNG_SETJMP_SUPPORTED
41#ifdef USE_FAR_KEYWORD
42 jmp_buf jmpbuf;
43#endif
44#endif
45
46 int i;
47
48 png_debug(1, "in png_create_read_struct\n");
49#ifdef PNG_USER_MEM_SUPPORTED
50 png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG,
51 (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr);
52#else
53 png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
54#endif
55 if (png_ptr == NULL)
56 return (NULL);
57
58 /* added at libpng-1.2.6 */
59#ifdef PNG_SET_USER_LIMITS_SUPPORTED
60 png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
61 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
62#endif
63
64#ifdef PNG_SETJMP_SUPPORTED
65#ifdef USE_FAR_KEYWORD
66 if (setjmp(jmpbuf))
67#else
68 if (setjmp(png_ptr->jmpbuf))
69#endif
70 {
71 png_free(png_ptr, png_ptr->zbuf);
72 png_ptr->zbuf=NULL;
73#ifdef PNG_USER_MEM_SUPPORTED
74 png_destroy_struct_2((png_voidp)png_ptr,
75 (png_free_ptr)free_fn, (png_voidp)mem_ptr);
76#else
77 png_destroy_struct((png_voidp)png_ptr);
78#endif
79 return (NULL);
80 }
81#ifdef USE_FAR_KEYWORD
82 png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
83#endif
84#endif
85
86#ifdef PNG_USER_MEM_SUPPORTED
87 png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn);
88#endif
89
90 png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn);
91
92 i=0;
93 do
94 {
95 if(user_png_ver[i] != png_libpng_ver[i])
96 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
97 } while (png_libpng_ver[i++]);
98
99 if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH)
100 {
101 /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so
102 * we must recompile any applications that use any older library version.
103 * For versions after libpng 1.0, we will be compatible, so we need
104 * only check the first digit.
105 */
106 if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] ||
107 (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) ||
108 (user_png_ver[0] == '0' && user_png_ver[2] < '9'))
109 {
110#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
111 char msg[80];
112 if (user_png_ver)
113 {
114 png_snprintf(msg, 80,
115 "Application was compiled with png.h from libpng-%.20s",
116 user_png_ver);
117 png_warning(png_ptr, msg);
118 }
119 png_snprintf(msg, 80,
120 "Application is running with png.c from libpng-%.20s",
121 png_libpng_ver);
122 png_warning(png_ptr, msg);
123#endif
124#ifdef PNG_ERROR_NUMBERS_SUPPORTED
125 png_ptr->flags=0;
126#endif
127 png_error(png_ptr,
128 "Incompatible libpng version in application and library");
129 }
130 }
131
132 /* initialize zbuf - compression buffer */
133 png_ptr->zbuf_size = PNG_ZBUF_SIZE;
134 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
135 (png_uint_32)png_ptr->zbuf_size);
136 png_ptr->zstream.zalloc = png_zalloc;
137 png_ptr->zstream.zfree = png_zfree;
138 png_ptr->zstream.opaque = (voidpf)png_ptr;
139
140 switch (inflateInit(&png_ptr->zstream))
141 {
142 case Z_OK: /* Do nothing */ break;
143 case Z_MEM_ERROR:
144 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break;
145 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break;
146 default: png_error(png_ptr, "Unknown zlib error");
147 }
148
149 png_ptr->zstream.next_out = png_ptr->zbuf;
150 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
151
152 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
153
154#ifdef PNG_SETJMP_SUPPORTED
155/* Applications that neglect to set up their own setjmp() and then encounter
156 a png_error() will longjmp here. Since the jmpbuf is then meaningless we
157 abort instead of returning. */
158#ifdef USE_FAR_KEYWORD
159 if (setjmp(jmpbuf))
160 PNG_ABORT();
161 png_memcpy(png_ptr->jmpbuf,jmpbuf,png_sizeof(jmp_buf));
162#else
163 if (setjmp(png_ptr->jmpbuf))
164 PNG_ABORT();
165#endif
166#endif
167 return (png_ptr);
168}
169
170#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
171/* Initialize PNG structure for reading, and allocate any memory needed.
172 This interface is deprecated in favour of the png_create_read_struct(),
173 and it will disappear as of libpng-1.3.0. */
174#undef png_read_init
175void PNGAPI
176png_read_init(png_structp png_ptr)
177{
178 /* We only come here via pre-1.0.7-compiled applications */
179 png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0);
180}
181
182void PNGAPI
183png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver,
184 png_size_t png_struct_size, png_size_t png_info_size)
185{
186 /* We only come here via pre-1.0.12-compiled applications */
187 if(png_ptr == NULL) return;
188#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)
189 if(png_sizeof(png_struct) > png_struct_size ||
190 png_sizeof(png_info) > png_info_size)
191 {
192 char msg[80];
193 png_ptr->warning_fn=NULL;
194 if (user_png_ver)
195 {
196 png_snprintf(msg, 80,
197 "Application was compiled with png.h from libpng-%.20s",
198 user_png_ver);
199 png_warning(png_ptr, msg);
200 }
201 png_snprintf(msg, 80,
202 "Application is running with png.c from libpng-%.20s",
203 png_libpng_ver);
204 png_warning(png_ptr, msg);
205 }
206#endif
207 if(png_sizeof(png_struct) > png_struct_size)
208 {
209 png_ptr->error_fn=NULL;
210#ifdef PNG_ERROR_NUMBERS_SUPPORTED
211 png_ptr->flags=0;
212#endif
213 png_error(png_ptr,
214 "The png struct allocated by the application for reading is too small.");
215 }
216 if(png_sizeof(png_info) > png_info_size)
217 {
218 png_ptr->error_fn=NULL;
219#ifdef PNG_ERROR_NUMBERS_SUPPORTED
220 png_ptr->flags=0;
221#endif
222 png_error(png_ptr,
223 "The info struct allocated by application for reading is too small.");
224 }
225 png_read_init_3(&png_ptr, user_png_ver, png_struct_size);
226}
227#endif /* PNG_1_0_X || PNG_1_2_X */
228
229void PNGAPI
230png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver,
231 png_size_t png_struct_size)
232{
233#ifdef PNG_SETJMP_SUPPORTED
234 jmp_buf tmp_jmp; /* to save current jump buffer */
235#endif
236
237 int i=0;
238
239 png_structp png_ptr=*ptr_ptr;
240
241 if(png_ptr == NULL) return;
242
243 do
244 {
245 if(user_png_ver[i] != png_libpng_ver[i])
246 {
247#ifdef PNG_LEGACY_SUPPORTED
248 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH;
249#else
250 png_ptr->warning_fn=NULL;
251 png_warning(png_ptr,
252 "Application uses deprecated png_read_init() and should be recompiled.");
253 break;
254#endif
255 }
256 } while (png_libpng_ver[i++]);
257
258 png_debug(1, "in png_read_init_3\n");
259
260#ifdef PNG_SETJMP_SUPPORTED
261 /* save jump buffer and error functions */
262 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
263#endif
264
265 if(png_sizeof(png_struct) > png_struct_size)
266 {
267 png_destroy_struct(png_ptr);
268 *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG);
269 png_ptr = *ptr_ptr;
270 }
271
272 /* reset all variables to 0 */
273 png_memset(png_ptr, 0, png_sizeof (png_struct));
274
275#ifdef PNG_SETJMP_SUPPORTED
276 /* restore jump buffer */
277 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
278#endif
279
280 /* added at libpng-1.2.6 */
281#ifdef PNG_SET_USER_LIMITS_SUPPORTED
282 png_ptr->user_width_max=PNG_USER_WIDTH_MAX;
283 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX;
284#endif
285
286 /* initialize zbuf - compression buffer */
287 png_ptr->zbuf_size = PNG_ZBUF_SIZE;
288 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr,
289 (png_uint_32)png_ptr->zbuf_size);
290 png_ptr->zstream.zalloc = png_zalloc;
291 png_ptr->zstream.zfree = png_zfree;
292 png_ptr->zstream.opaque = (voidpf)png_ptr;
293
294 switch (inflateInit(&png_ptr->zstream))
295 {
296 case Z_OK: /* Do nothing */ break;
297 case Z_MEM_ERROR:
298 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break;
299 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break;
300 default: png_error(png_ptr, "Unknown zlib error");
301 }
302
303 png_ptr->zstream.next_out = png_ptr->zbuf;
304 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
305
306 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL);
307}
308
309#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
310/* Read the information before the actual image data. This has been
311 * changed in v0.90 to allow reading a file that already has the magic
312 * bytes read from the stream. You can tell libpng how many bytes have
313 * been read from the beginning of the stream (up to the maximum of 8)
314 * via png_set_sig_bytes(), and we will only check the remaining bytes
315 * here. The application can then have access to the signature bytes we
316 * read if it is determined that this isn't a valid PNG file.
317 */
318void PNGAPI
319png_read_info(png_structp png_ptr, png_infop info_ptr)
320{
321 if(png_ptr == NULL) return;
322 png_debug(1, "in png_read_info\n");
323 /* If we haven't checked all of the PNG signature bytes, do so now. */
324 if (png_ptr->sig_bytes < 8)
325 {
326 png_size_t num_checked = png_ptr->sig_bytes,
327 num_to_check = 8 - num_checked;
328
329 png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check);
330 png_ptr->sig_bytes = 8;
331
332 if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
333 {
334 if (num_checked < 4 &&
335 png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
336 png_error(png_ptr, "Not a PNG file");
337 else
338 png_error(png_ptr, "PNG file corrupted by ASCII conversion");
339 }
340 if (num_checked < 3)
341 png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
342 }
343
344 for(;;)
345 {
346#ifdef PNG_USE_LOCAL_ARRAYS
347 PNG_CONST PNG_IHDR;
348 PNG_CONST PNG_IDAT;
349 PNG_CONST PNG_IEND;
350 PNG_CONST PNG_PLTE;
351#if defined(PNG_READ_bKGD_SUPPORTED)
352 PNG_CONST PNG_bKGD;
353#endif
354#if defined(PNG_READ_cHRM_SUPPORTED)
355 PNG_CONST PNG_cHRM;
356#endif
357#if defined(PNG_READ_gAMA_SUPPORTED)
358 PNG_CONST PNG_gAMA;
359#endif
360#if defined(PNG_READ_hIST_SUPPORTED)
361 PNG_CONST PNG_hIST;
362#endif
363#if defined(PNG_READ_iCCP_SUPPORTED)
364 PNG_CONST PNG_iCCP;
365#endif
366#if defined(PNG_READ_iTXt_SUPPORTED)
367 PNG_CONST PNG_iTXt;
368#endif
369#if defined(PNG_READ_oFFs_SUPPORTED)
370 PNG_CONST PNG_oFFs;
371#endif
372#if defined(PNG_READ_pCAL_SUPPORTED)
373 PNG_CONST PNG_pCAL;
374#endif
375#if defined(PNG_READ_pHYs_SUPPORTED)
376 PNG_CONST PNG_pHYs;
377#endif
378#if defined(PNG_READ_sBIT_SUPPORTED)
379 PNG_CONST PNG_sBIT;
380#endif
381#if defined(PNG_READ_sCAL_SUPPORTED)
382 PNG_CONST PNG_sCAL;
383#endif
384#if defined(PNG_READ_sPLT_SUPPORTED)
385 PNG_CONST PNG_sPLT;
386#endif
387#if defined(PNG_READ_sRGB_SUPPORTED)
388 PNG_CONST PNG_sRGB;
389#endif
390#if defined(PNG_READ_tEXt_SUPPORTED)
391 PNG_CONST PNG_tEXt;
392#endif
393#if defined(PNG_READ_tIME_SUPPORTED)
394 PNG_CONST PNG_tIME;
395#endif
396#if defined(PNG_READ_tRNS_SUPPORTED)
397 PNG_CONST PNG_tRNS;
398#endif
399#if defined(PNG_READ_zTXt_SUPPORTED)
400 PNG_CONST PNG_zTXt;
401#endif
402#endif /* PNG_USE_LOCAL_ARRAYS */
403 png_byte chunk_length[4];
404 png_uint_32 length;
405
406 png_read_data(png_ptr, chunk_length, 4);
407 length = png_get_uint_31(png_ptr,chunk_length);
408
409 png_reset_crc(png_ptr);
410 png_crc_read(png_ptr, png_ptr->chunk_name, 4);
411
412 png_debug2(0, "Reading %s chunk, length=%lu.\n", png_ptr->chunk_name,
413 length);
414
415 /* This should be a binary subdivision search or a hash for
416 * matching the chunk name rather than a linear search.
417 */
418 if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
419 if(png_ptr->mode & PNG_AFTER_IDAT)
420 png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
421
422 if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
423 png_handle_IHDR(png_ptr, info_ptr, length);
424 else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
425 png_handle_IEND(png_ptr, info_ptr, length);
426#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
427 else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
428 {
429 if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
430 png_ptr->mode |= PNG_HAVE_IDAT;
431 png_handle_unknown(png_ptr, info_ptr, length);
432 if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
433 png_ptr->mode |= PNG_HAVE_PLTE;
434 else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
435 {
436 if (!(png_ptr->mode & PNG_HAVE_IHDR))
437 png_error(png_ptr, "Missing IHDR before IDAT");
438 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
439 !(png_ptr->mode & PNG_HAVE_PLTE))
440 png_error(png_ptr, "Missing PLTE before IDAT");
441 break;
442 }
443 }
444#endif
445 else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
446 png_handle_PLTE(png_ptr, info_ptr, length);
447 else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
448 {
449 if (!(png_ptr->mode & PNG_HAVE_IHDR))
450 png_error(png_ptr, "Missing IHDR before IDAT");
451 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
452 !(png_ptr->mode & PNG_HAVE_PLTE))
453 png_error(png_ptr, "Missing PLTE before IDAT");
454
455 png_ptr->idat_size = length;
456 png_ptr->mode |= PNG_HAVE_IDAT;
457 break;
458 }
459#if defined(PNG_READ_bKGD_SUPPORTED)
460 else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
461 png_handle_bKGD(png_ptr, info_ptr, length);
462#endif
463#if defined(PNG_READ_cHRM_SUPPORTED)
464 else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
465 png_handle_cHRM(png_ptr, info_ptr, length);
466#endif
467#if defined(PNG_READ_gAMA_SUPPORTED)
468 else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
469 png_handle_gAMA(png_ptr, info_ptr, length);
470#endif
471#if defined(PNG_READ_hIST_SUPPORTED)
472 else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
473 png_handle_hIST(png_ptr, info_ptr, length);
474#endif
475#if defined(PNG_READ_oFFs_SUPPORTED)
476 else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
477 png_handle_oFFs(png_ptr, info_ptr, length);
478#endif
479#if defined(PNG_READ_pCAL_SUPPORTED)
480 else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
481 png_handle_pCAL(png_ptr, info_ptr, length);
482#endif
483#if defined(PNG_READ_sCAL_SUPPORTED)
484 else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
485 png_handle_sCAL(png_ptr, info_ptr, length);
486#endif
487#if defined(PNG_READ_pHYs_SUPPORTED)
488 else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
489 png_handle_pHYs(png_ptr, info_ptr, length);
490#endif
491#if defined(PNG_READ_sBIT_SUPPORTED)
492 else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
493 png_handle_sBIT(png_ptr, info_ptr, length);
494#endif
495#if defined(PNG_READ_sRGB_SUPPORTED)
496 else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
497 png_handle_sRGB(png_ptr, info_ptr, length);
498#endif
499#if defined(PNG_READ_iCCP_SUPPORTED)
500 else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
501 png_handle_iCCP(png_ptr, info_ptr, length);
502#endif
503#if defined(PNG_READ_sPLT_SUPPORTED)
504 else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
505 png_handle_sPLT(png_ptr, info_ptr, length);
506#endif
507#if defined(PNG_READ_tEXt_SUPPORTED)
508 else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
509 png_handle_tEXt(png_ptr, info_ptr, length);
510#endif
511#if defined(PNG_READ_tIME_SUPPORTED)
512 else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
513 png_handle_tIME(png_ptr, info_ptr, length);
514#endif
515#if defined(PNG_READ_tRNS_SUPPORTED)
516 else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
517 png_handle_tRNS(png_ptr, info_ptr, length);
518#endif
519#if defined(PNG_READ_zTXt_SUPPORTED)
520 else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
521 png_handle_zTXt(png_ptr, info_ptr, length);
522#endif
523#if defined(PNG_READ_iTXt_SUPPORTED)
524 else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
525 png_handle_iTXt(png_ptr, info_ptr, length);
526#endif
527 else
528 png_handle_unknown(png_ptr, info_ptr, length);
529 }
530}
531#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
532
533/* optional call to update the users info_ptr structure */
534void PNGAPI
535png_read_update_info(png_structp png_ptr, png_infop info_ptr)
536{
537 png_debug(1, "in png_read_update_info\n");
538 if(png_ptr == NULL) return;
539 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
540 png_read_start_row(png_ptr);
541 else
542 png_warning(png_ptr,
543 "Ignoring extra png_read_update_info() call; row buffer not reallocated");
544 png_read_transform_info(png_ptr, info_ptr);
545}
546
547#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
548/* Initialize palette, background, etc, after transformations
549 * are set, but before any reading takes place. This allows
550 * the user to obtain a gamma-corrected palette, for example.
551 * If the user doesn't call this, we will do it ourselves.
552 */
553void PNGAPI
554png_start_read_image(png_structp png_ptr)
555{
556 png_debug(1, "in png_start_read_image\n");
557 if(png_ptr == NULL) return;
558 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
559 png_read_start_row(png_ptr);
560}
561#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
562
563#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
564void PNGAPI
565png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
566{
567#ifdef PNG_USE_LOCAL_ARRAYS
568 PNG_CONST PNG_IDAT;
569 PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55,
570 0xff};
571 PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
572#endif
573 int ret;
574 if(png_ptr == NULL) return;
575 png_debug2(1, "in png_read_row (row %lu, pass %d)\n",
576 png_ptr->row_number, png_ptr->pass);
577 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
578 png_read_start_row(png_ptr);
579 if (png_ptr->row_number == 0 && png_ptr->pass == 0)
580 {
581 /* check for transforms that have been set but were defined out */
582#if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
583 if (png_ptr->transformations & PNG_INVERT_MONO)
584 png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined.");
585#endif
586#if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
587 if (png_ptr->transformations & PNG_FILLER)
588 png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined.");
589#endif
590#if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED)
591 if (png_ptr->transformations & PNG_PACKSWAP)
592 png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined.");
593#endif
594#if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
595 if (png_ptr->transformations & PNG_PACK)
596 png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined.");
597#endif
598#if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
599 if (png_ptr->transformations & PNG_SHIFT)
600 png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined.");
601#endif
602#if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
603 if (png_ptr->transformations & PNG_BGR)
604 png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined.");
605#endif
606#if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
607 if (png_ptr->transformations & PNG_SWAP_BYTES)
608 png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined.");
609#endif
610 }
611
612#if defined(PNG_READ_INTERLACING_SUPPORTED)
613 /* if interlaced and we do not need a new row, combine row and return */
614 if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
615 {
616 switch (png_ptr->pass)
617 {
618 case 0:
619 if (png_ptr->row_number & 0x07)
620 {
621 if (dsp_row != NULL)
622 png_combine_row(png_ptr, dsp_row,
623 png_pass_dsp_mask[png_ptr->pass]);
624 png_read_finish_row(png_ptr);
625 return;
626 }
627 break;
628 case 1:
629 if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
630 {
631 if (dsp_row != NULL)
632 png_combine_row(png_ptr, dsp_row,
633 png_pass_dsp_mask[png_ptr->pass]);
634 png_read_finish_row(png_ptr);
635 return;
636 }
637 break;
638 case 2:
639 if ((png_ptr->row_number & 0x07) != 4)
640 {
641 if (dsp_row != NULL && (png_ptr->row_number & 4))
642 png_combine_row(png_ptr, dsp_row,
643 png_pass_dsp_mask[png_ptr->pass]);
644 png_read_finish_row(png_ptr);
645 return;
646 }
647 break;
648 case 3:
649 if ((png_ptr->row_number & 3) || png_ptr->width < 3)
650 {
651 if (dsp_row != NULL)
652 png_combine_row(png_ptr, dsp_row,
653 png_pass_dsp_mask[png_ptr->pass]);
654 png_read_finish_row(png_ptr);
655 return;
656 }
657 break;
658 case 4:
659 if ((png_ptr->row_number & 3) != 2)
660 {
661 if (dsp_row != NULL && (png_ptr->row_number & 2))
662 png_combine_row(png_ptr, dsp_row,
663 png_pass_dsp_mask[png_ptr->pass]);
664 png_read_finish_row(png_ptr);
665 return;
666 }
667 break;
668 case 5:
669 if ((png_ptr->row_number & 1) || png_ptr->width < 2)
670 {
671 if (dsp_row != NULL)
672 png_combine_row(png_ptr, dsp_row,
673 png_pass_dsp_mask[png_ptr->pass]);
674 png_read_finish_row(png_ptr);
675 return;
676 }
677 break;
678 case 6:
679 if (!(png_ptr->row_number & 1))
680 {
681 png_read_finish_row(png_ptr);
682 return;
683 }
684 break;
685 }
686 }
687#endif
688
689 if (!(png_ptr->mode & PNG_HAVE_IDAT))
690 png_error(png_ptr, "Invalid attempt to read row data");
691
692 png_ptr->zstream.next_out = png_ptr->row_buf;
693 png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
694 do
695 {
696 if (!(png_ptr->zstream.avail_in))
697 {
698 while (!png_ptr->idat_size)
699 {
700 png_byte chunk_length[4];
701
702 png_crc_finish(png_ptr, 0);
703
704 png_read_data(png_ptr, chunk_length, 4);
705 png_ptr->idat_size = png_get_uint_31(png_ptr,chunk_length);
706
707 png_reset_crc(png_ptr);
708 png_crc_read(png_ptr, png_ptr->chunk_name, 4);
709 if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
710 png_error(png_ptr, "Not enough image data");
711 }
712 png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
713 png_ptr->zstream.next_in = png_ptr->zbuf;
714 if (png_ptr->zbuf_size > png_ptr->idat_size)
715 png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
716 png_crc_read(png_ptr, png_ptr->zbuf,
717 (png_size_t)png_ptr->zstream.avail_in);
718 png_ptr->idat_size -= png_ptr->zstream.avail_in;
719 }
720 ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
721 if (ret == Z_STREAM_END)
722 {
723 if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in ||
724 png_ptr->idat_size)
725 png_error(png_ptr, "Extra compressed data");
726 png_ptr->mode |= PNG_AFTER_IDAT;
727 png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
728 break;
729 }
730 if (ret != Z_OK)
731 png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
732 "Decompression error");
733
734 } while (png_ptr->zstream.avail_out);
735
736 png_ptr->row_info.color_type = png_ptr->color_type;
737 png_ptr->row_info.width = png_ptr->iwidth;
738 png_ptr->row_info.channels = png_ptr->channels;
739 png_ptr->row_info.bit_depth = png_ptr->bit_depth;
740 png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
741 png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth,
742 png_ptr->row_info.width);
743
744 if(png_ptr->row_buf[0])
745 png_read_filter_row(png_ptr, &(png_ptr->row_info),
746 png_ptr->row_buf + 1, png_ptr->prev_row + 1,
747 (int)(png_ptr->row_buf[0]));
748
749 png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
750 png_ptr->rowbytes + 1);
751
752#if defined(PNG_MNG_FEATURES_SUPPORTED)
753 if((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
754 (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
755 {
756 /* Intrapixel differencing */
757 png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1);
758 }
759#endif
760
761
762 if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA))
763 png_do_read_transformations(png_ptr);
764
765#if defined(PNG_READ_INTERLACING_SUPPORTED)
766 /* blow up interlaced rows to full size */
767 if (png_ptr->interlaced &&
768 (png_ptr->transformations & PNG_INTERLACE))
769 {
770 if (png_ptr->pass < 6)
771/* old interface (pre-1.0.9):
772 png_do_read_interlace(&(png_ptr->row_info),
773 png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
774 */
775 png_do_read_interlace(png_ptr);
776
777 if (dsp_row != NULL)
778 png_combine_row(png_ptr, dsp_row,
779 png_pass_dsp_mask[png_ptr->pass]);
780 if (row != NULL)
781 png_combine_row(png_ptr, row,
782 png_pass_mask[png_ptr->pass]);
783 }
784 else
785#endif
786 {
787 if (row != NULL)
788 png_combine_row(png_ptr, row, 0xff);
789 if (dsp_row != NULL)
790 png_combine_row(png_ptr, dsp_row, 0xff);
791 }
792 png_read_finish_row(png_ptr);
793
794 if (png_ptr->read_row_fn != NULL)
795 (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);
796}
797#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
798
799#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
800/* Read one or more rows of image data. If the image is interlaced,
801 * and png_set_interlace_handling() has been called, the rows need to
802 * contain the contents of the rows from the previous pass. If the
803 * image has alpha or transparency, and png_handle_alpha()[*] has been
804 * called, the rows contents must be initialized to the contents of the
805 * screen.
806 *
807 * "row" holds the actual image, and pixels are placed in it
808 * as they arrive. If the image is displayed after each pass, it will
809 * appear to "sparkle" in. "display_row" can be used to display a
810 * "chunky" progressive image, with finer detail added as it becomes
811 * available. If you do not want this "chunky" display, you may pass
812 * NULL for display_row. If you do not want the sparkle display, and
813 * you have not called png_handle_alpha(), you may pass NULL for rows.
814 * If you have called png_handle_alpha(), and the image has either an
815 * alpha channel or a transparency chunk, you must provide a buffer for
816 * rows. In this case, you do not have to provide a display_row buffer
817 * also, but you may. If the image is not interlaced, or if you have
818 * not called png_set_interlace_handling(), the display_row buffer will
819 * be ignored, so pass NULL to it.
820 *
821 * [*] png_handle_alpha() does not exist yet, as of this version of libpng
822 */
823
824void PNGAPI
825png_read_rows(png_structp png_ptr, png_bytepp row,
826 png_bytepp display_row, png_uint_32 num_rows)
827{
828 png_uint_32 i;
829 png_bytepp rp;
830 png_bytepp dp;
831
832 png_debug(1, "in png_read_rows\n");
833 if(png_ptr == NULL) return;
834 rp = row;
835 dp = display_row;
836 if (rp != NULL && dp != NULL)
837 for (i = 0; i < num_rows; i++)
838 {
839 png_bytep rptr = *rp++;
840 png_bytep dptr = *dp++;
841
842 png_read_row(png_ptr, rptr, dptr);
843 }
844 else if(rp != NULL)
845 for (i = 0; i < num_rows; i++)
846 {
847 png_bytep rptr = *rp;
848 png_read_row(png_ptr, rptr, png_bytep_NULL);
849 rp++;
850 }
851 else if(dp != NULL)
852 for (i = 0; i < num_rows; i++)
853 {
854 png_bytep dptr = *dp;
855 png_read_row(png_ptr, png_bytep_NULL, dptr);
856 dp++;
857 }
858}
859#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
860
861#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
862/* Read the entire image. If the image has an alpha channel or a tRNS
863 * chunk, and you have called png_handle_alpha()[*], you will need to
864 * initialize the image to the current image that PNG will be overlaying.
865 * We set the num_rows again here, in case it was incorrectly set in
866 * png_read_start_row() by a call to png_read_update_info() or
867 * png_start_read_image() if png_set_interlace_handling() wasn't called
868 * prior to either of these functions like it should have been. You can
869 * only call this function once. If you desire to have an image for
870 * each pass of a interlaced image, use png_read_rows() instead.
871 *
872 * [*] png_handle_alpha() does not exist yet, as of this version of libpng
873 */
874void PNGAPI
875png_read_image(png_structp png_ptr, png_bytepp image)
876{
877 png_uint_32 i,image_height;
878 int pass, j;
879 png_bytepp rp;
880
881 png_debug(1, "in png_read_image\n");
882 if(png_ptr == NULL) return;
883
884#ifdef PNG_READ_INTERLACING_SUPPORTED
885 pass = png_set_interlace_handling(png_ptr);
886#else
887 if (png_ptr->interlaced)
888 png_error(png_ptr,
889 "Cannot read interlaced image -- interlace handler disabled.");
890 pass = 1;
891#endif
892
893
894 image_height=png_ptr->height;
895 png_ptr->num_rows = image_height; /* Make sure this is set correctly */
896
897 for (j = 0; j < pass; j++)
898 {
899 rp = image;
900 for (i = 0; i < image_height; i++)
901 {
902 png_read_row(png_ptr, *rp, png_bytep_NULL);
903 rp++;
904 }
905 }
906}
907#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
908
909#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
910/* Read the end of the PNG file. Will not read past the end of the
911 * file, will verify the end is accurate, and will read any comments
912 * or time information at the end of the file, if info is not NULL.
913 */
914void PNGAPI
915png_read_end(png_structp png_ptr, png_infop info_ptr)
916{
917 png_byte chunk_length[4];
918 png_uint_32 length;
919
920 png_debug(1, "in png_read_end\n");
921 if(png_ptr == NULL) return;
922 png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */
923
924 do
925 {
926#ifdef PNG_USE_LOCAL_ARRAYS
927 PNG_CONST PNG_IHDR;
928 PNG_CONST PNG_IDAT;
929 PNG_CONST PNG_IEND;
930 PNG_CONST PNG_PLTE;
931#if defined(PNG_READ_bKGD_SUPPORTED)
932 PNG_CONST PNG_bKGD;
933#endif
934#if defined(PNG_READ_cHRM_SUPPORTED)
935 PNG_CONST PNG_cHRM;
936#endif
937#if defined(PNG_READ_gAMA_SUPPORTED)
938 PNG_CONST PNG_gAMA;
939#endif
940#if defined(PNG_READ_hIST_SUPPORTED)
941 PNG_CONST PNG_hIST;
942#endif
943#if defined(PNG_READ_iCCP_SUPPORTED)
944 PNG_CONST PNG_iCCP;
945#endif
946#if defined(PNG_READ_iTXt_SUPPORTED)
947 PNG_CONST PNG_iTXt;
948#endif
949#if defined(PNG_READ_oFFs_SUPPORTED)
950 PNG_CONST PNG_oFFs;
951#endif
952#if defined(PNG_READ_pCAL_SUPPORTED)
953 PNG_CONST PNG_pCAL;
954#endif
955#if defined(PNG_READ_pHYs_SUPPORTED)
956 PNG_CONST PNG_pHYs;
957#endif
958#if defined(PNG_READ_sBIT_SUPPORTED)
959 PNG_CONST PNG_sBIT;
960#endif
961#if defined(PNG_READ_sCAL_SUPPORTED)
962 PNG_CONST PNG_sCAL;
963#endif
964#if defined(PNG_READ_sPLT_SUPPORTED)
965 PNG_CONST PNG_sPLT;
966#endif
967#if defined(PNG_READ_sRGB_SUPPORTED)
968 PNG_CONST PNG_sRGB;
969#endif
970#if defined(PNG_READ_tEXt_SUPPORTED)
971 PNG_CONST PNG_tEXt;
972#endif
973#if defined(PNG_READ_tIME_SUPPORTED)
974 PNG_CONST PNG_tIME;
975#endif
976#if defined(PNG_READ_tRNS_SUPPORTED)
977 PNG_CONST PNG_tRNS;
978#endif
979#if defined(PNG_READ_zTXt_SUPPORTED)
980 PNG_CONST PNG_zTXt;
981#endif
982#endif /* PNG_USE_LOCAL_ARRAYS */
983
984 png_read_data(png_ptr, chunk_length, 4);
985 length = png_get_uint_31(png_ptr,chunk_length);
986
987 png_reset_crc(png_ptr);
988 png_crc_read(png_ptr, png_ptr->chunk_name, 4);
989
990 png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
991
992 if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
993 png_handle_IHDR(png_ptr, info_ptr, length);
994 else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
995 png_handle_IEND(png_ptr, info_ptr, length);
996#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
997 else if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name))
998 {
999 if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
1000 {
1001 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
1002 png_error(png_ptr, "Too many IDAT's found");
1003 }
1004 png_handle_unknown(png_ptr, info_ptr, length);
1005 if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
1006 png_ptr->mode |= PNG_HAVE_PLTE;
1007 }
1008#endif
1009 else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
1010 {
1011 /* Zero length IDATs are legal after the last IDAT has been
1012 * read, but not after other chunks have been read.
1013 */
1014 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
1015 png_error(png_ptr, "Too many IDAT's found");
1016 png_crc_finish(png_ptr, length);
1017 }
1018 else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
1019 png_handle_PLTE(png_ptr, info_ptr, length);
1020#if defined(PNG_READ_bKGD_SUPPORTED)
1021 else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
1022 png_handle_bKGD(png_ptr, info_ptr, length);
1023#endif
1024#if defined(PNG_READ_cHRM_SUPPORTED)
1025 else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
1026 png_handle_cHRM(png_ptr, info_ptr, length);
1027#endif
1028#if defined(PNG_READ_gAMA_SUPPORTED)
1029 else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
1030 png_handle_gAMA(png_ptr, info_ptr, length);
1031#endif
1032#if defined(PNG_READ_hIST_SUPPORTED)
1033 else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
1034 png_handle_hIST(png_ptr, info_ptr, length);
1035#endif
1036#if defined(PNG_READ_oFFs_SUPPORTED)
1037 else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
1038 png_handle_oFFs(png_ptr, info_ptr, length);
1039#endif
1040#if defined(PNG_READ_pCAL_SUPPORTED)
1041 else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
1042 png_handle_pCAL(png_ptr, info_ptr, length);
1043#endif
1044#if defined(PNG_READ_sCAL_SUPPORTED)
1045 else if (!png_memcmp(png_ptr->chunk_name, png_sCAL, 4))
1046 png_handle_sCAL(png_ptr, info_ptr, length);
1047#endif
1048#if defined(PNG_READ_pHYs_SUPPORTED)
1049 else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
1050 png_handle_pHYs(png_ptr, info_ptr, length);
1051#endif
1052#if defined(PNG_READ_sBIT_SUPPORTED)
1053 else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
1054 png_handle_sBIT(png_ptr, info_ptr, length);
1055#endif
1056#if defined(PNG_READ_sRGB_SUPPORTED)
1057 else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
1058 png_handle_sRGB(png_ptr, info_ptr, length);
1059#endif
1060#if defined(PNG_READ_iCCP_SUPPORTED)
1061 else if (!png_memcmp(png_ptr->chunk_name, png_iCCP, 4))
1062 png_handle_iCCP(png_ptr, info_ptr, length);
1063#endif
1064#if defined(PNG_READ_sPLT_SUPPORTED)
1065 else if (!png_memcmp(png_ptr->chunk_name, png_sPLT, 4))
1066 png_handle_sPLT(png_ptr, info_ptr, length);
1067#endif
1068#if defined(PNG_READ_tEXt_SUPPORTED)
1069 else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
1070 png_handle_tEXt(png_ptr, info_ptr, length);
1071#endif
1072#if defined(PNG_READ_tIME_SUPPORTED)
1073 else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
1074 png_handle_tIME(png_ptr, info_ptr, length);
1075#endif
1076#if defined(PNG_READ_tRNS_SUPPORTED)
1077 else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
1078 png_handle_tRNS(png_ptr, info_ptr, length);
1079#endif
1080#if defined(PNG_READ_zTXt_SUPPORTED)
1081 else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
1082 png_handle_zTXt(png_ptr, info_ptr, length);
1083#endif
1084#if defined(PNG_READ_iTXt_SUPPORTED)
1085 else if (!png_memcmp(png_ptr->chunk_name, png_iTXt, 4))
1086 png_handle_iTXt(png_ptr, info_ptr, length);
1087#endif
1088 else
1089 png_handle_unknown(png_ptr, info_ptr, length);
1090 } while (!(png_ptr->mode & PNG_HAVE_IEND));
1091}
1092#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
1093
1094/* free all memory used by the read */
1095void PNGAPI
1096png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr,
1097 png_infopp end_info_ptr_ptr)
1098{
1099 png_structp png_ptr = NULL;
1100 png_infop info_ptr = NULL, end_info_ptr = NULL;
1101#ifdef PNG_USER_MEM_SUPPORTED
1102 png_free_ptr free_fn = NULL;
1103 png_voidp mem_ptr = NULL;
1104#endif
1105
1106 png_debug(1, "in png_destroy_read_struct\n");
1107 if (png_ptr_ptr != NULL)
1108 {
1109 png_ptr = *png_ptr_ptr;
1110#ifdef PNG_USER_MEM_SUPPORTED
1111 free_fn = png_ptr->free_fn;
1112 mem_ptr = png_ptr->mem_ptr;
1113#endif
1114 }
1115
1116 if (info_ptr_ptr != NULL)
1117 info_ptr = *info_ptr_ptr;
1118
1119 if (end_info_ptr_ptr != NULL)
1120 end_info_ptr = *end_info_ptr_ptr;
1121
1122 png_read_destroy(png_ptr, info_ptr, end_info_ptr);
1123
1124 if (info_ptr != NULL)
1125 {
1126#if defined(PNG_TEXT_SUPPORTED)
1127 png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1);
1128#endif
1129
1130#ifdef PNG_USER_MEM_SUPPORTED
1131 png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn,
1132 (png_voidp)mem_ptr);
1133#else
1134 png_destroy_struct((png_voidp)info_ptr);
1135#endif
1136 *info_ptr_ptr = NULL;
1137 }
1138
1139 if (end_info_ptr != NULL)
1140 {
1141#if defined(PNG_READ_TEXT_SUPPORTED)
1142 png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1);
1143#endif
1144#ifdef PNG_USER_MEM_SUPPORTED
1145 png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn,
1146 (png_voidp)mem_ptr);
1147#else
1148 png_destroy_struct((png_voidp)end_info_ptr);
1149#endif
1150 *end_info_ptr_ptr = NULL;
1151 }
1152
1153 if (png_ptr != NULL)
1154 {
1155#ifdef PNG_USER_MEM_SUPPORTED
1156 png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn,
1157 (png_voidp)mem_ptr);
1158#else
1159 png_destroy_struct((png_voidp)png_ptr);
1160#endif
1161 *png_ptr_ptr = NULL;
1162 }
1163}
1164
1165/* free all memory used by the read (old method) */
1166void /* PRIVATE */
1167png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr)
1168{
1169#ifdef PNG_SETJMP_SUPPORTED
1170 jmp_buf tmp_jmp;
1171#endif
1172 png_error_ptr error_fn;
1173 png_error_ptr warning_fn;
1174 png_voidp error_ptr;
1175#ifdef PNG_USER_MEM_SUPPORTED
1176 png_free_ptr free_fn;
1177#endif
1178
1179 png_debug(1, "in png_read_destroy\n");
1180 if (info_ptr != NULL)
1181 png_info_destroy(png_ptr, info_ptr);
1182
1183 if (end_info_ptr != NULL)
1184 png_info_destroy(png_ptr, end_info_ptr);
1185
1186 png_free(png_ptr, png_ptr->zbuf);
1187 png_free(png_ptr, png_ptr->big_row_buf);
1188 png_free(png_ptr, png_ptr->prev_row);
1189#if defined(PNG_READ_DITHER_SUPPORTED)
1190 png_free(png_ptr, png_ptr->palette_lookup);
1191 png_free(png_ptr, png_ptr->dither_index);
1192#endif
1193#if defined(PNG_READ_GAMMA_SUPPORTED)
1194 png_free(png_ptr, png_ptr->gamma_table);
1195#endif
1196#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1197 png_free(png_ptr, png_ptr->gamma_from_1);
1198 png_free(png_ptr, png_ptr->gamma_to_1);
1199#endif
1200#ifdef PNG_FREE_ME_SUPPORTED
1201 if (png_ptr->free_me & PNG_FREE_PLTE)
1202 png_zfree(png_ptr, png_ptr->palette);
1203 png_ptr->free_me &= ~PNG_FREE_PLTE;
1204#else
1205 if (png_ptr->flags & PNG_FLAG_FREE_PLTE)
1206 png_zfree(png_ptr, png_ptr->palette);
1207 png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
1208#endif
1209#if defined(PNG_tRNS_SUPPORTED) || \
1210 defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
1211#ifdef PNG_FREE_ME_SUPPORTED
1212 if (png_ptr->free_me & PNG_FREE_TRNS)
1213 png_free(png_ptr, png_ptr->trans);
1214 png_ptr->free_me &= ~PNG_FREE_TRNS;
1215#else
1216 if (png_ptr->flags & PNG_FLAG_FREE_TRNS)
1217 png_free(png_ptr, png_ptr->trans);
1218 png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
1219#endif
1220#endif
1221#if defined(PNG_READ_hIST_SUPPORTED)
1222#ifdef PNG_FREE_ME_SUPPORTED
1223 if (png_ptr->free_me & PNG_FREE_HIST)
1224 png_free(png_ptr, png_ptr->hist);
1225 png_ptr->free_me &= ~PNG_FREE_HIST;
1226#else
1227 if (png_ptr->flags & PNG_FLAG_FREE_HIST)
1228 png_free(png_ptr, png_ptr->hist);
1229 png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
1230#endif
1231#endif
1232#if defined(PNG_READ_GAMMA_SUPPORTED)
1233 if (png_ptr->gamma_16_table != NULL)
1234 {
1235 int i;
1236 int istop = (1 << (8 - png_ptr->gamma_shift));
1237 for (i = 0; i < istop; i++)
1238 {
1239 png_free(png_ptr, png_ptr->gamma_16_table[i]);
1240 }
1241 png_free(png_ptr, png_ptr->gamma_16_table);
1242 }
1243#if defined(PNG_READ_BACKGROUND_SUPPORTED)
1244 if (png_ptr->gamma_16_from_1 != NULL)
1245 {
1246 int i;
1247 int istop = (1 << (8 - png_ptr->gamma_shift));
1248 for (i = 0; i < istop; i++)
1249 {
1250 png_free(png_ptr, png_ptr->gamma_16_from_1[i]);
1251 }
1252 png_free(png_ptr, png_ptr->gamma_16_from_1);
1253 }
1254 if (png_ptr->gamma_16_to_1 != NULL)
1255 {
1256 int i;
1257 int istop = (1 << (8 - png_ptr->gamma_shift));
1258 for (i = 0; i < istop; i++)
1259 {
1260 png_free(png_ptr, png_ptr->gamma_16_to_1[i]);
1261 }
1262 png_free(png_ptr, png_ptr->gamma_16_to_1);
1263 }
1264#endif
1265#endif
1266#if defined(PNG_TIME_RFC1123_SUPPORTED)
1267 png_free(png_ptr, png_ptr->time_buffer);
1268#endif
1269
1270 inflateEnd(&png_ptr->zstream);
1271#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1272 png_free(png_ptr, png_ptr->save_buffer);
1273#endif
1274
1275#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1276#ifdef PNG_TEXT_SUPPORTED
1277 png_free(png_ptr, png_ptr->current_text);
1278#endif /* PNG_TEXT_SUPPORTED */
1279#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1280
1281 /* Save the important info out of the png_struct, in case it is
1282 * being used again.
1283 */
1284#ifdef PNG_SETJMP_SUPPORTED
1285 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof (jmp_buf));
1286#endif
1287
1288 error_fn = png_ptr->error_fn;
1289 warning_fn = png_ptr->warning_fn;
1290 error_ptr = png_ptr->error_ptr;
1291#ifdef PNG_USER_MEM_SUPPORTED
1292 free_fn = png_ptr->free_fn;
1293#endif
1294
1295 png_memset(png_ptr, 0, png_sizeof (png_struct));
1296
1297 png_ptr->error_fn = error_fn;
1298 png_ptr->warning_fn = warning_fn;
1299 png_ptr->error_ptr = error_ptr;
1300#ifdef PNG_USER_MEM_SUPPORTED
1301 png_ptr->free_fn = free_fn;
1302#endif
1303
1304#ifdef PNG_SETJMP_SUPPORTED
1305 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof (jmp_buf));
1306#endif
1307
1308}
1309
1310void PNGAPI
1311png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn)
1312{
1313 if(png_ptr == NULL) return;
1314 png_ptr->read_row_fn = read_row_fn;
1315}
1316
1317
1318#ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED
1319#if defined(PNG_INFO_IMAGE_SUPPORTED)
1320void PNGAPI
1321png_read_png(png_structp png_ptr, png_infop info_ptr,
1322 int transforms,
1323 voidp params)
1324{
1325 int row;
1326
1327 if(png_ptr == NULL) return;
1328#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED)
1329 /* invert the alpha channel from opacity to transparency
1330 */
1331 if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
1332 png_set_invert_alpha(png_ptr);
1333#endif
1334
1335 /* png_read_info() gives us all of the information from the
1336 * PNG file before the first IDAT (image data chunk).
1337 */
1338 png_read_info(png_ptr, info_ptr);
1339 if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep))
1340 png_error(png_ptr,"Image is too high to process with png_read_png()");
1341
1342 /* -------------- image transformations start here ------------------- */
1343
1344#if defined(PNG_READ_16_TO_8_SUPPORTED)
1345 /* tell libpng to strip 16 bit/color files down to 8 bits per color
1346 */
1347 if (transforms & PNG_TRANSFORM_STRIP_16)
1348 png_set_strip_16(png_ptr);
1349#endif
1350
1351#if defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1352 /* Strip alpha bytes from the input data without combining with
1353 * the background (not recommended).
1354 */
1355 if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
1356 png_set_strip_alpha(png_ptr);
1357#endif
1358
1359#if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED)
1360 /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
1361 * byte into separate bytes (useful for paletted and grayscale images).
1362 */
1363 if (transforms & PNG_TRANSFORM_PACKING)
1364 png_set_packing(png_ptr);
1365#endif
1366
1367#if defined(PNG_READ_PACKSWAP_SUPPORTED)
1368 /* Change the order of packed pixels to least significant bit first
1369 * (not useful if you are using png_set_packing).
1370 */
1371 if (transforms & PNG_TRANSFORM_PACKSWAP)
1372 png_set_packswap(png_ptr);
1373#endif
1374
1375#if defined(PNG_READ_EXPAND_SUPPORTED)
1376 /* Expand paletted colors into true RGB triplets
1377 * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel
1378 * Expand paletted or RGB images with transparency to full alpha
1379 * channels so the data will be available as RGBA quartets.
1380 */
1381 if (transforms & PNG_TRANSFORM_EXPAND)
1382 if ((png_ptr->bit_depth < 8) ||
1383 (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ||
1384 (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)))
1385 png_set_expand(png_ptr);
1386#endif
1387
1388 /* We don't handle background color or gamma transformation or dithering.
1389 */
1390
1391#if defined(PNG_READ_INVERT_SUPPORTED)
1392 /* invert monochrome files to have 0 as white and 1 as black
1393 */
1394 if (transforms & PNG_TRANSFORM_INVERT_MONO)
1395 png_set_invert_mono(png_ptr);
1396#endif
1397
1398#if defined(PNG_READ_SHIFT_SUPPORTED)
1399 /* If you want to shift the pixel values from the range [0,255] or
1400 * [0,65535] to the original [0,7] or [0,31], or whatever range the
1401 * colors were originally in:
1402 */
1403 if ((transforms & PNG_TRANSFORM_SHIFT)
1404 && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
1405 {
1406 png_color_8p sig_bit;
1407
1408 png_get_sBIT(png_ptr, info_ptr, &sig_bit);
1409 png_set_shift(png_ptr, sig_bit);
1410 }
1411#endif
1412
1413#if defined(PNG_READ_BGR_SUPPORTED)
1414 /* flip the RGB pixels to BGR (or RGBA to BGRA)
1415 */
1416 if (transforms & PNG_TRANSFORM_BGR)
1417 png_set_bgr(png_ptr);
1418#endif
1419
1420#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED)
1421 /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR)
1422 */
1423 if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
1424 png_set_swap_alpha(png_ptr);
1425#endif
1426
1427#if defined(PNG_READ_SWAP_SUPPORTED)
1428 /* swap bytes of 16 bit files to least significant byte first
1429 */
1430 if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
1431 png_set_swap(png_ptr);
1432#endif
1433
1434 /* We don't handle adding filler bytes */
1435
1436 /* Optional call to gamma correct and add the background to the palette
1437 * and update info structure. REQUIRED if you are expecting libpng to
1438 * update the palette for you (i.e., you selected such a transform above).
1439 */
1440 png_read_update_info(png_ptr, info_ptr);
1441
1442 /* -------------- image transformations end here ------------------- */
1443
1444#ifdef PNG_FREE_ME_SUPPORTED
1445 png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
1446#endif
1447 if(info_ptr->row_pointers == NULL)
1448 {
1449 info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr,
1450 info_ptr->height * png_sizeof(png_bytep));
1451#ifdef PNG_FREE_ME_SUPPORTED
1452 info_ptr->free_me |= PNG_FREE_ROWS;
1453#endif
1454 for (row = 0; row < (int)info_ptr->height; row++)
1455 {
1456 info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr,
1457 png_get_rowbytes(png_ptr, info_ptr));
1458 }
1459 }
1460
1461 png_read_image(png_ptr, info_ptr->row_pointers);
1462 info_ptr->valid |= PNG_INFO_IDAT;
1463
1464 /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
1465 png_read_end(png_ptr, info_ptr);
1466
1467 transforms = transforms; /* quiet compiler warnings */
1468 params = params;
1469
1470}
1471#endif /* PNG_INFO_IMAGE_SUPPORTED */
1472#endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */
1473#endif /* PNG_READ_SUPPORTED */
1474