source: liacs/MIR2010/Sample/cximage/png/png.c@ 93

Last change on this file since 93 was 93, checked in by Rick van der Zwet, 15 years ago

Sample implementation of professor
File size: 25.2 KB
RevLine 
[93]1
2/* png.c - location for general purpose libpng functions
3 *
4 * Last changed in libpng 1.2.17 May 15, 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
11#define PNG_INTERNAL
12#define PNG_NO_EXTERN
13#include "png.h"
14
15/* Generate a compiler error if there is an old png.h in the search path. */
16typedef version_1_2_18 Your_png_h_is_not_version_1_2_18;
17
18/* Version information for C files. This had better match the version
19 * string defined in png.h. */
20
21#ifdef PNG_USE_GLOBAL_ARRAYS
22/* png_libpng_ver was changed to a function in version 1.0.5c */
23const char png_libpng_ver[18] = PNG_LIBPNG_VER_STRING;
24
25#ifdef PNG_READ_SUPPORTED
26
27/* png_sig was changed to a function in version 1.0.5c */
28/* Place to hold the signature string for a PNG file. */
29const png_byte FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
30#endif /* PNG_READ_SUPPORTED */
31
32/* Invoke global declarations for constant strings for known chunk types */
33PNG_IHDR;
34PNG_IDAT;
35PNG_IEND;
36PNG_PLTE;
37PNG_bKGD;
38PNG_cHRM;
39PNG_gAMA;
40PNG_hIST;
41PNG_iCCP;
42PNG_iTXt;
43PNG_oFFs;
44PNG_pCAL;
45PNG_sCAL;
46PNG_pHYs;
47PNG_sBIT;
48PNG_sPLT;
49PNG_sRGB;
50PNG_tEXt;
51PNG_tIME;
52PNG_tRNS;
53PNG_zTXt;
54
55#ifdef PNG_READ_SUPPORTED
56/* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
57
58/* start of interlace block */
59const int FARDATA png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
60
61/* offset to next interlace block */
62const int FARDATA png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
63
64/* start of interlace block in the y direction */
65const int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
66
67/* offset to next interlace block in the y direction */
68const int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
69
70/* width of interlace block (used in assembler routines only) */
71#ifdef PNG_HAVE_MMX_COMBINE_ROW
72const int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
73#endif
74
75/* Height of interlace block. This is not currently used - if you need
76 * it, uncomment it here and in png.h
77const int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
78*/
79
80/* Mask to determine which pixels are valid in a pass */
81const int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
82
83/* Mask to determine which pixels to overwrite while displaying */
84const int FARDATA png_pass_dsp_mask[]
85 = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
86
87#endif /* PNG_READ_SUPPORTED */
88#endif /* PNG_USE_GLOBAL_ARRAYS */
89
90/* Tells libpng that we have already handled the first "num_bytes" bytes
91 * of the PNG file signature. If the PNG data is embedded into another
92 * stream we can set num_bytes = 8 so that libpng will not attempt to read
93 * or write any of the magic bytes before it starts on the IHDR.
94 */
95
96#ifdef PNG_READ_SUPPORTED
97void PNGAPI
98png_set_sig_bytes(png_structp png_ptr, int num_bytes)
99{
100 if(png_ptr == NULL) return;
101 png_debug(1, "in png_set_sig_bytes\n");
102 if (num_bytes > 8)
103 png_error(png_ptr, "Too many bytes for PNG signature.");
104
105 png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
106}
107
108/* Checks whether the supplied bytes match the PNG signature. We allow
109 * checking less than the full 8-byte signature so that those apps that
110 * already read the first few bytes of a file to determine the file type
111 * can simply check the remaining bytes for extra assurance. Returns
112 * an integer less than, equal to, or greater than zero if sig is found,
113 * respectively, to be less than, to match, or be greater than the correct
114 * PNG signature (this is the same behaviour as strcmp, memcmp, etc).
115 */
116int PNGAPI
117png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
118{
119 png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
120 if (num_to_check > 8)
121 num_to_check = 8;
122 else if (num_to_check < 1)
123 return (-1);
124
125 if (start > 7)
126 return (-1);
127
128 if (start + num_to_check > 8)
129 num_to_check = 8 - start;
130
131 return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
132}
133
134#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
135/* (Obsolete) function to check signature bytes. It does not allow one
136 * to check a partial signature. This function might be removed in the
137 * future - use png_sig_cmp(). Returns true (nonzero) if the file is a PNG.
138 */
139int PNGAPI
140png_check_sig(png_bytep sig, int num)
141{
142 return ((int)!png_sig_cmp(sig, (png_size_t)0, (png_size_t)num));
143}
144#endif
145#endif /* PNG_READ_SUPPORTED */
146
147#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
148/* Function to allocate memory for zlib and clear it to 0. */
149#ifdef PNG_1_0_X
150voidpf PNGAPI
151#else
152voidpf /* private */
153#endif
154png_zalloc(voidpf png_ptr, uInt items, uInt size)
155{
156 png_voidp ptr;
157 png_structp p=(png_structp)png_ptr;
158 png_uint_32 save_flags=p->flags;
159 png_uint_32 num_bytes;
160
161 if(png_ptr == NULL) return (NULL);
162 if (items > PNG_UINT_32_MAX/size)
163 {
164 png_warning (p, "Potential overflow in png_zalloc()");
165 return (NULL);
166 }
167 num_bytes = (png_uint_32)items * size;
168
169 p->flags|=PNG_FLAG_MALLOC_NULL_MEM_OK;
170 ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
171 p->flags=save_flags;
172
173#if defined(PNG_1_0_X) && !defined(PNG_NO_ZALLOC_ZERO)
174 if (ptr == NULL)
175 return ((voidpf)ptr);
176
177 if (num_bytes > (png_uint_32)0x8000L)
178 {
179 png_memset(ptr, 0, (png_size_t)0x8000L);
180 png_memset((png_bytep)ptr + (png_size_t)0x8000L, 0,
181 (png_size_t)(num_bytes - (png_uint_32)0x8000L));
182 }
183 else
184 {
185 png_memset(ptr, 0, (png_size_t)num_bytes);
186 }
187#endif
188 return ((voidpf)ptr);
189}
190
191/* function to free memory for zlib */
192#ifdef PNG_1_0_X
193void PNGAPI
194#else
195void /* private */
196#endif
197png_zfree(voidpf png_ptr, voidpf ptr)
198{
199 png_free((png_structp)png_ptr, (png_voidp)ptr);
200}
201
202/* Reset the CRC variable to 32 bits of 1's. Care must be taken
203 * in case CRC is > 32 bits to leave the top bits 0.
204 */
205void /* PRIVATE */
206png_reset_crc(png_structp png_ptr)
207{
208 png_ptr->crc = crc32(0, Z_NULL, 0);
209}
210
211/* Calculate the CRC over a section of data. We can only pass as
212 * much data to this routine as the largest single buffer size. We
213 * also check that this data will actually be used before going to the
214 * trouble of calculating it.
215 */
216void /* PRIVATE */
217png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length)
218{
219 int need_crc = 1;
220
221 if (png_ptr->chunk_name[0] & 0x20) /* ancillary */
222 {
223 if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
224 (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
225 need_crc = 0;
226 }
227 else /* critical */
228 {
229 if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
230 need_crc = 0;
231 }
232
233 if (need_crc)
234 png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length);
235}
236
237/* Allocate the memory for an info_struct for the application. We don't
238 * really need the png_ptr, but it could potentially be useful in the
239 * future. This should be used in favour of malloc(png_sizeof(png_info))
240 * and png_info_init() so that applications that want to use a shared
241 * libpng don't have to be recompiled if png_info changes size.
242 */
243png_infop PNGAPI
244png_create_info_struct(png_structp png_ptr)
245{
246 png_infop info_ptr;
247
248 png_debug(1, "in png_create_info_struct\n");
249 if(png_ptr == NULL) return (NULL);
250#ifdef PNG_USER_MEM_SUPPORTED
251 info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
252 png_ptr->malloc_fn, png_ptr->mem_ptr);
253#else
254 info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
255#endif
256 if (info_ptr != NULL)
257 png_info_init_3(&info_ptr, png_sizeof(png_info));
258
259 return (info_ptr);
260}
261
262/* This function frees the memory associated with a single info struct.
263 * Normally, one would use either png_destroy_read_struct() or
264 * png_destroy_write_struct() to free an info struct, but this may be
265 * useful for some applications.
266 */
267void PNGAPI
268png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
269{
270 png_infop info_ptr = NULL;
271 if(png_ptr == NULL) return;
272
273 png_debug(1, "in png_destroy_info_struct\n");
274 if (info_ptr_ptr != NULL)
275 info_ptr = *info_ptr_ptr;
276
277 if (info_ptr != NULL)
278 {
279 png_info_destroy(png_ptr, info_ptr);
280
281#ifdef PNG_USER_MEM_SUPPORTED
282 png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn,
283 png_ptr->mem_ptr);
284#else
285 png_destroy_struct((png_voidp)info_ptr);
286#endif
287 *info_ptr_ptr = NULL;
288 }
289}
290
291/* Initialize the info structure. This is now an internal function (0.89)
292 * and applications using it are urged to use png_create_info_struct()
293 * instead.
294 */
295#if defined(PNG_1_0_X) || defined(PNG_1_2_X)
296#undef png_info_init
297void PNGAPI
298png_info_init(png_infop info_ptr)
299{
300 /* We only come here via pre-1.0.12-compiled applications */
301 png_info_init_3(&info_ptr, 0);
302}
303#endif
304
305void PNGAPI
306png_info_init_3(png_infopp ptr_ptr, png_size_t png_info_struct_size)
307{
308 png_infop info_ptr = *ptr_ptr;
309
310 if(info_ptr == NULL) return;
311
312 png_debug(1, "in png_info_init_3\n");
313
314 if(png_sizeof(png_info) > png_info_struct_size)
315 {
316 png_destroy_struct(info_ptr);
317 info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO);
318 *ptr_ptr = info_ptr;
319 }
320
321 /* set everything to 0 */
322 png_memset(info_ptr, 0, png_sizeof (png_info));
323}
324
325#ifdef PNG_FREE_ME_SUPPORTED
326void PNGAPI
327png_data_freer(png_structp png_ptr, png_infop info_ptr,
328 int freer, png_uint_32 mask)
329{
330 png_debug(1, "in png_data_freer\n");
331 if (png_ptr == NULL || info_ptr == NULL)
332 return;
333 if(freer == PNG_DESTROY_WILL_FREE_DATA)
334 info_ptr->free_me |= mask;
335 else if(freer == PNG_USER_WILL_FREE_DATA)
336 info_ptr->free_me &= ~mask;
337 else
338 png_warning(png_ptr,
339 "Unknown freer parameter in png_data_freer.");
340}
341#endif
342
343void PNGAPI
344png_free_data(png_structp png_ptr, png_infop info_ptr, png_uint_32 mask,
345 int num)
346{
347 png_debug(1, "in png_free_data\n");
348 if (png_ptr == NULL || info_ptr == NULL)
349 return;
350
351#if defined(PNG_TEXT_SUPPORTED)
352/* free text item num or (if num == -1) all text items */
353#ifdef PNG_FREE_ME_SUPPORTED
354if ((mask & PNG_FREE_TEXT) & info_ptr->free_me)
355#else
356if (mask & PNG_FREE_TEXT)
357#endif
358{
359 if (num != -1)
360 {
361 if (info_ptr->text && info_ptr->text[num].key)
362 {
363 png_free(png_ptr, info_ptr->text[num].key);
364 info_ptr->text[num].key = NULL;
365 }
366 }
367 else
368 {
369 int i;
370 for (i = 0; i < info_ptr->num_text; i++)
371 png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, i);
372 png_free(png_ptr, info_ptr->text);
373 info_ptr->text = NULL;
374 info_ptr->num_text=0;
375 }
376}
377#endif
378
379#if defined(PNG_tRNS_SUPPORTED)
380/* free any tRNS entry */
381#ifdef PNG_FREE_ME_SUPPORTED
382if ((mask & PNG_FREE_TRNS) & info_ptr->free_me)
383#else
384if ((mask & PNG_FREE_TRNS) && (png_ptr->flags & PNG_FLAG_FREE_TRNS))
385#endif
386{
387 png_free(png_ptr, info_ptr->trans);
388 info_ptr->valid &= ~PNG_INFO_tRNS;
389#ifndef PNG_FREE_ME_SUPPORTED
390 png_ptr->flags &= ~PNG_FLAG_FREE_TRNS;
391#endif
392 info_ptr->trans = NULL;
393}
394#endif
395
396#if defined(PNG_sCAL_SUPPORTED)
397/* free any sCAL entry */
398#ifdef PNG_FREE_ME_SUPPORTED
399if ((mask & PNG_FREE_SCAL) & info_ptr->free_me)
400#else
401if (mask & PNG_FREE_SCAL)
402#endif
403{
404#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
405 png_free(png_ptr, info_ptr->scal_s_width);
406 png_free(png_ptr, info_ptr->scal_s_height);
407 info_ptr->scal_s_width = NULL;
408 info_ptr->scal_s_height = NULL;
409#endif
410 info_ptr->valid &= ~PNG_INFO_sCAL;
411}
412#endif
413
414#if defined(PNG_pCAL_SUPPORTED)
415/* free any pCAL entry */
416#ifdef PNG_FREE_ME_SUPPORTED
417if ((mask & PNG_FREE_PCAL) & info_ptr->free_me)
418#else
419if (mask & PNG_FREE_PCAL)
420#endif
421{
422 png_free(png_ptr, info_ptr->pcal_purpose);
423 png_free(png_ptr, info_ptr->pcal_units);
424 info_ptr->pcal_purpose = NULL;
425 info_ptr->pcal_units = NULL;
426 if (info_ptr->pcal_params != NULL)
427 {
428 int i;
429 for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
430 {
431 png_free(png_ptr, info_ptr->pcal_params[i]);
432 info_ptr->pcal_params[i]=NULL;
433 }
434 png_free(png_ptr, info_ptr->pcal_params);
435 info_ptr->pcal_params = NULL;
436 }
437 info_ptr->valid &= ~PNG_INFO_pCAL;
438}
439#endif
440
441#if defined(PNG_iCCP_SUPPORTED)
442/* free any iCCP entry */
443#ifdef PNG_FREE_ME_SUPPORTED
444if ((mask & PNG_FREE_ICCP) & info_ptr->free_me)
445#else
446if (mask & PNG_FREE_ICCP)
447#endif
448{
449 png_free(png_ptr, info_ptr->iccp_name);
450 png_free(png_ptr, info_ptr->iccp_profile);
451 info_ptr->iccp_name = NULL;
452 info_ptr->iccp_profile = NULL;
453 info_ptr->valid &= ~PNG_INFO_iCCP;
454}
455#endif
456
457#if defined(PNG_sPLT_SUPPORTED)
458/* free a given sPLT entry, or (if num == -1) all sPLT entries */
459#ifdef PNG_FREE_ME_SUPPORTED
460if ((mask & PNG_FREE_SPLT) & info_ptr->free_me)
461#else
462if (mask & PNG_FREE_SPLT)
463#endif
464{
465 if (num != -1)
466 {
467 if(info_ptr->splt_palettes)
468 {
469 png_free(png_ptr, info_ptr->splt_palettes[num].name);
470 png_free(png_ptr, info_ptr->splt_palettes[num].entries);
471 info_ptr->splt_palettes[num].name = NULL;
472 info_ptr->splt_palettes[num].entries = NULL;
473 }
474 }
475 else
476 {
477 if(info_ptr->splt_palettes_num)
478 {
479 int i;
480 for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
481 png_free_data(png_ptr, info_ptr, PNG_FREE_SPLT, i);
482
483 png_free(png_ptr, info_ptr->splt_palettes);
484 info_ptr->splt_palettes = NULL;
485 info_ptr->splt_palettes_num = 0;
486 }
487 info_ptr->valid &= ~PNG_INFO_sPLT;
488 }
489}
490#endif
491
492#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
493 if(png_ptr->unknown_chunk.data)
494 {
495 png_free(png_ptr, png_ptr->unknown_chunk.data);
496 png_ptr->unknown_chunk.data = NULL;
497 }
498#ifdef PNG_FREE_ME_SUPPORTED
499if ((mask & PNG_FREE_UNKN) & info_ptr->free_me)
500#else
501if (mask & PNG_FREE_UNKN)
502#endif
503{
504 if (num != -1)
505 {
506 if(info_ptr->unknown_chunks)
507 {
508 png_free(png_ptr, info_ptr->unknown_chunks[num].data);
509 info_ptr->unknown_chunks[num].data = NULL;
510 }
511 }
512 else
513 {
514 int i;
515
516 if(info_ptr->unknown_chunks_num)
517 {
518 for (i = 0; i < (int)info_ptr->unknown_chunks_num; i++)
519 png_free_data(png_ptr, info_ptr, PNG_FREE_UNKN, i);
520
521 png_free(png_ptr, info_ptr->unknown_chunks);
522 info_ptr->unknown_chunks = NULL;
523 info_ptr->unknown_chunks_num = 0;
524 }
525 }
526}
527#endif
528
529#if defined(PNG_hIST_SUPPORTED)
530/* free any hIST entry */
531#ifdef PNG_FREE_ME_SUPPORTED
532if ((mask & PNG_FREE_HIST) & info_ptr->free_me)
533#else
534if ((mask & PNG_FREE_HIST) && (png_ptr->flags & PNG_FLAG_FREE_HIST))
535#endif
536{
537 png_free(png_ptr, info_ptr->hist);
538 info_ptr->hist = NULL;
539 info_ptr->valid &= ~PNG_INFO_hIST;
540#ifndef PNG_FREE_ME_SUPPORTED
541 png_ptr->flags &= ~PNG_FLAG_FREE_HIST;
542#endif
543}
544#endif
545
546/* free any PLTE entry that was internally allocated */
547#ifdef PNG_FREE_ME_SUPPORTED
548if ((mask & PNG_FREE_PLTE) & info_ptr->free_me)
549#else
550if ((mask & PNG_FREE_PLTE) && (png_ptr->flags & PNG_FLAG_FREE_PLTE))
551#endif
552{
553 png_zfree(png_ptr, info_ptr->palette);
554 info_ptr->palette = NULL;
555 info_ptr->valid &= ~PNG_INFO_PLTE;
556#ifndef PNG_FREE_ME_SUPPORTED
557 png_ptr->flags &= ~PNG_FLAG_FREE_PLTE;
558#endif
559 info_ptr->num_palette = 0;
560}
561
562#if defined(PNG_INFO_IMAGE_SUPPORTED)
563/* free any image bits attached to the info structure */
564#ifdef PNG_FREE_ME_SUPPORTED
565if ((mask & PNG_FREE_ROWS) & info_ptr->free_me)
566#else
567if (mask & PNG_FREE_ROWS)
568#endif
569{
570 if(info_ptr->row_pointers)
571 {
572 int row;
573 for (row = 0; row < (int)info_ptr->height; row++)
574 {
575 png_free(png_ptr, info_ptr->row_pointers[row]);
576 info_ptr->row_pointers[row]=NULL;
577 }
578 png_free(png_ptr, info_ptr->row_pointers);
579 info_ptr->row_pointers=NULL;
580 }
581 info_ptr->valid &= ~PNG_INFO_IDAT;
582}
583#endif
584
585#ifdef PNG_FREE_ME_SUPPORTED
586 if(num == -1)
587 info_ptr->free_me &= ~mask;
588 else
589 info_ptr->free_me &= ~(mask & ~PNG_FREE_MUL);
590#endif
591}
592
593/* This is an internal routine to free any memory that the info struct is
594 * pointing to before re-using it or freeing the struct itself. Recall
595 * that png_free() checks for NULL pointers for us.
596 */
597void /* PRIVATE */
598png_info_destroy(png_structp png_ptr, png_infop info_ptr)
599{
600 png_debug(1, "in png_info_destroy\n");
601
602 png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
603
604#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
605 if (png_ptr->num_chunk_list)
606 {
607 png_free(png_ptr, png_ptr->chunk_list);
608 png_ptr->chunk_list=NULL;
609 png_ptr->num_chunk_list=0;
610 }
611#endif
612
613 png_info_init_3(&info_ptr, png_sizeof(png_info));
614}
615#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
616
617/* This function returns a pointer to the io_ptr associated with the user
618 * functions. The application should free any memory associated with this
619 * pointer before png_write_destroy() or png_read_destroy() are called.
620 */
621png_voidp PNGAPI
622png_get_io_ptr(png_structp png_ptr)
623{
624 if(png_ptr == NULL) return (NULL);
625 return (png_ptr->io_ptr);
626}
627
628#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
629#if !defined(PNG_NO_STDIO)
630/* Initialize the default input/output functions for the PNG file. If you
631 * use your own read or write routines, you can call either png_set_read_fn()
632 * or png_set_write_fn() instead of png_init_io(). If you have defined
633 * PNG_NO_STDIO, you must use a function of your own because "FILE *" isn't
634 * necessarily available.
635 */
636void PNGAPI
637png_init_io(png_structp png_ptr, png_FILE_p fp)
638{
639 png_debug(1, "in png_init_io\n");
640 if(png_ptr == NULL) return;
641 png_ptr->io_ptr = (png_voidp)fp;
642}
643#endif
644
645#if defined(PNG_TIME_RFC1123_SUPPORTED)
646/* Convert the supplied time into an RFC 1123 string suitable for use in
647 * a "Creation Time" or other text-based time string.
648 */
649png_charp PNGAPI
650png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
651{
652 static PNG_CONST char short_months[12][4] =
653 {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
654 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
655
656 if(png_ptr == NULL) return (NULL);
657 if (png_ptr->time_buffer == NULL)
658 {
659 png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
660 png_sizeof(char)));
661 }
662
663#if defined(_WIN32_WCE)
664 {
665 wchar_t time_buf[29];
666 wsprintf(time_buf, TEXT("%d %S %d %02d:%02d:%02d +0000"),
667 ptime->day % 32, short_months[(ptime->month - 1) % 12],
668 ptime->year, ptime->hour % 24, ptime->minute % 60,
669 ptime->second % 61);
670 WideCharToMultiByte(CP_ACP, 0, time_buf, -1, png_ptr->time_buffer, 29,
671 NULL, NULL);
672 }
673#else
674#ifdef USE_FAR_KEYWORD
675 {
676 char near_time_buf[29];
677 sprintf(near_time_buf, "%d %s %d %02d:%02d:%02d +0000",
678 ptime->day % 32, short_months[(ptime->month - 1) % 12],
679 ptime->year, ptime->hour % 24, ptime->minute % 60,
680 ptime->second % 61);
681 png_memcpy(png_ptr->time_buffer, near_time_buf,
682 29*png_sizeof(char));
683 }
684#else
685 sprintf(png_ptr->time_buffer, "%d %s %d %02d:%02d:%02d +0000",
686 ptime->day % 32, short_months[(ptime->month - 1) % 12],
687 ptime->year, ptime->hour % 24, ptime->minute % 60,
688 ptime->second % 61);
689#endif
690#endif /* _WIN32_WCE */
691 return ((png_charp)png_ptr->time_buffer);
692}
693#endif /* PNG_TIME_RFC1123_SUPPORTED */
694
695#if 0
696/* Signature string for a PNG file. */
697png_bytep PNGAPI
698png_sig_bytes(void)
699{
700 return ((png_bytep)"\211\120\116\107\015\012\032\012");
701}
702#endif
703#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
704
705png_charp PNGAPI
706png_get_copyright(png_structp png_ptr)
707{
708 if (&png_ptr != NULL) /* silence compiler warning about unused png_ptr */
709 return ((png_charp) "\n libpng version 1.2.18 - May 15, 2007\n\
710 Copyright (c) 1998-2007 Glenn Randers-Pehrson\n\
711 Copyright (c) 1996-1997 Andreas Dilger\n\
712 Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.\n");
713 return ((png_charp) "");
714}
715
716/* The following return the library version as a short string in the
717 * format 1.0.0 through 99.99.99zz. To get the version of *.h files
718 * used with your application, print out PNG_LIBPNG_VER_STRING, which
719 * is defined in png.h.
720 * Note: now there is no difference between png_get_libpng_ver() and
721 * png_get_header_ver(). Due to the version_nn_nn_nn typedef guard,
722 * it is guaranteed that png.c uses the correct version of png.h.
723 */
724png_charp PNGAPI
725png_get_libpng_ver(png_structp png_ptr)
726{
727 /* Version of *.c files used when building libpng */
728 if (&png_ptr != NULL) /* silence compiler warning about unused png_ptr */
729 return ((png_charp) PNG_LIBPNG_VER_STRING);
730 return ((png_charp) "");
731}
732
733png_charp PNGAPI
734png_get_header_ver(png_structp png_ptr)
735{
736 /* Version of *.h files used when building libpng */
737 if (&png_ptr != NULL) /* silence compiler warning about unused png_ptr */
738 return ((png_charp) PNG_LIBPNG_VER_STRING);
739 return ((png_charp) "");
740}
741
742png_charp PNGAPI
743png_get_header_version(png_structp png_ptr)
744{
745 /* Returns longer string containing both version and date */
746 if (&png_ptr != NULL) /* silence compiler warning about unused png_ptr */
747 return ((png_charp) PNG_HEADER_VERSION_STRING);
748 return ((png_charp) "");
749}
750
751#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
752#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
753int PNGAPI
754png_handle_as_unknown(png_structp png_ptr, png_bytep chunk_name)
755{
756 /* check chunk_name and return "keep" value if it's on the list, else 0 */
757 int i;
758 png_bytep p;
759 if((png_ptr == NULL && chunk_name == NULL) || png_ptr->num_chunk_list<=0)
760 return 0;
761 p=png_ptr->chunk_list+png_ptr->num_chunk_list*5-5;
762 for (i = png_ptr->num_chunk_list; i; i--, p-=5)
763 if (!png_memcmp(chunk_name, p, 4))
764 return ((int)*(p+4));
765 return 0;
766}
767#endif
768
769/* This function, added to libpng-1.0.6g, is untested. */
770int PNGAPI
771png_reset_zstream(png_structp png_ptr)
772{
773 if (png_ptr == NULL) return Z_STREAM_ERROR;
774 return (inflateReset(&png_ptr->zstream));
775}
776#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
777
778/* This function was added to libpng-1.0.7 */
779png_uint_32 PNGAPI
780png_access_version_number(void)
781{
782 /* Version of *.c files used when building libpng */
783 return((png_uint_32) PNG_LIBPNG_VER);
784}
785
786
787#if defined(PNG_READ_SUPPORTED) && defined(PNG_ASSEMBLER_CODE_SUPPORTED)
788#if !defined(PNG_1_0_X)
789#if defined(PNG_MMX_CODE_SUPPORTED)
790/* this INTERNAL function was added to libpng 1.2.0 */
791void /* PRIVATE */
792png_init_mmx_flags (png_structp png_ptr)
793{
794 if(png_ptr == NULL) return;
795 png_ptr->mmx_rowbytes_threshold = 0;
796 png_ptr->mmx_bitdepth_threshold = 0;
797
798# if (defined(PNG_USE_PNGVCRD) || defined(PNG_USE_PNGGCCRD))
799
800 png_ptr->asm_flags |= PNG_ASM_FLAG_MMX_SUPPORT_COMPILED;
801
802 if (png_mmx_support() > 0) {
803 png_ptr->asm_flags |= PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU
804# ifdef PNG_HAVE_MMX_COMBINE_ROW
805 | PNG_ASM_FLAG_MMX_READ_COMBINE_ROW
806# endif
807# ifdef PNG_HAVE_MMX_READ_INTERLACE
808 | PNG_ASM_FLAG_MMX_READ_INTERLACE
809# endif
810# ifndef PNG_HAVE_MMX_READ_FILTER_ROW
811 ;
812# else
813 | PNG_ASM_FLAG_MMX_READ_FILTER_SUB
814 | PNG_ASM_FLAG_MMX_READ_FILTER_UP
815 | PNG_ASM_FLAG_MMX_READ_FILTER_AVG
816 | PNG_ASM_FLAG_MMX_READ_FILTER_PAETH ;
817
818 png_ptr->mmx_rowbytes_threshold = PNG_MMX_ROWBYTES_THRESHOLD_DEFAULT;
819 png_ptr->mmx_bitdepth_threshold = PNG_MMX_BITDEPTH_THRESHOLD_DEFAULT;
820# endif
821 } else {
822 png_ptr->asm_flags &= ~( PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU
823 | PNG_MMX_READ_FLAGS
824 | PNG_MMX_WRITE_FLAGS );
825 }
826
827# else /* !(PNGVCRD || PNGGCCRD) */
828
829 /* clear all MMX flags; no support is compiled in */
830 png_ptr->asm_flags &= ~( PNG_MMX_FLAGS );
831
832# endif /* ?(PNGVCRD || PNGGCCRD) */
833}
834
835#endif /* !(PNG_MMX_CODE_SUPPORTED) */
836
837/* this function was added to libpng 1.2.0 */
838#if !defined(PNG_USE_PNGGCCRD) && \
839 !(defined(PNG_MMX_CODE_SUPPORTED) && defined(PNG_USE_PNGVCRD))
840int PNGAPI
841png_mmx_support(void)
842{
843 return -1;
844}
845#endif
846#endif /* PNG_1_0_X && PNG_ASSEMBLER_CODE_SUPPORTED */
847#endif /* PNG_READ_SUPPORTED */
848
849#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
850#ifdef PNG_SIZE_T
851/* Added at libpng version 1.2.6 */
852 PNG_EXTERN png_size_t PNGAPI png_convert_size PNGARG((size_t size));
853png_size_t PNGAPI
854png_convert_size(size_t size)
855{
856 if (size > (png_size_t)-1)
857 PNG_ABORT(); /* We haven't got access to png_ptr, so no png_error() */
858 return ((png_size_t)size);
859}
860#endif /* PNG_SIZE_T */
861#endif /* defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) */
Note: See TracBrowser for help on using the repository browser.