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1 | ||
2 | /* pngerror.c - stub functions for i/o and memory allocation | |
3 | * | |
4 | * Last changed in libpng 1.5.7 [December 15, 2011] | |
5 | * Copyright (c) 1998-2011 Glenn Randers-Pehrson | |
6 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) | |
7 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) | |
8 | * | |
9 | * This code is released under the libpng license. | |
10 | * For conditions of distribution and use, see the disclaimer | |
11 | * and license in png.h | |
12 | * | |
13 | * This file provides a location for all error handling. Users who | |
14 | * need special error handling are expected to write replacement functions | |
15 | * and use png_set_error_fn() to use those functions. See the instructions | |
16 | * at each function. | |
17 | */ | |
18 | ||
19 | #include "pngpriv.h" | |
20 | ||
21 | #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) | |
22 | ||
23 | static PNG_FUNCTION(void, png_default_error,PNGARG((png_structp png_ptr, | |
24 | png_const_charp error_message)),PNG_NORETURN); | |
25 | ||
26 | #ifdef PNG_WARNINGS_SUPPORTED | |
27 | static void /* PRIVATE */ | |
28 | png_default_warning PNGARG((png_structp png_ptr, | |
29 | png_const_charp warning_message)); | |
30 | #endif /* PNG_WARNINGS_SUPPORTED */ | |
31 | ||
32 | /* This function is called whenever there is a fatal error. This function | |
33 | * should not be changed. If there is a need to handle errors differently, | |
34 | * you should supply a replacement error function and use png_set_error_fn() | |
35 | * to replace the error function at run-time. | |
36 | */ | |
37 | #ifdef PNG_ERROR_TEXT_SUPPORTED | |
38 | PNG_FUNCTION(void,PNGAPI | |
39 | png_error,(png_structp png_ptr, png_const_charp error_message),PNG_NORETURN) | |
40 | { | |
41 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
42 | char msg[16]; | |
43 | if (png_ptr != NULL) | |
44 | { | |
45 | if (png_ptr->flags& | |
46 | (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) | |
47 | { | |
48 | if (*error_message == PNG_LITERAL_SHARP) | |
49 | { | |
50 | /* Strip "#nnnn " from beginning of error message. */ | |
51 | int offset; | |
52 | for (offset = 1; offset<15; offset++) | |
53 | if (error_message[offset] == ' ') | |
54 | break; | |
55 | ||
56 | if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) | |
57 | { | |
58 | int i; | |
59 | for (i = 0; i < offset - 1; i++) | |
60 | msg[i] = error_message[i + 1]; | |
61 | msg[i - 1] = '\0'; | |
62 | error_message = msg; | |
63 | } | |
64 | ||
65 | else | |
66 | error_message += offset; | |
67 | } | |
68 | ||
69 | else | |
70 | { | |
71 | if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) | |
72 | { | |
73 | msg[0] = '0'; | |
74 | msg[1] = '\0'; | |
75 | error_message = msg; | |
76 | } | |
77 | } | |
78 | } | |
79 | } | |
80 | #endif | |
81 | if (png_ptr != NULL && png_ptr->error_fn != NULL) | |
82 | (*(png_ptr->error_fn))(png_ptr, error_message); | |
83 | ||
84 | /* If the custom handler doesn't exist, or if it returns, | |
85 | use the default handler, which will not return. */ | |
86 | png_default_error(png_ptr, error_message); | |
87 | } | |
88 | #else | |
89 | PNG_FUNCTION(void,PNGAPI | |
90 | png_err,(png_structp png_ptr),PNG_NORETURN) | |
91 | { | |
92 | /* Prior to 1.5.2 the error_fn received a NULL pointer, expressed | |
93 | * erroneously as '\0', instead of the empty string "". This was | |
94 | * apparently an error, introduced in libpng-1.2.20, and png_default_error | |
95 | * will crash in this case. | |
96 | */ | |
97 | if (png_ptr != NULL && png_ptr->error_fn != NULL) | |
98 | (*(png_ptr->error_fn))(png_ptr, ""); | |
99 | ||
100 | /* If the custom handler doesn't exist, or if it returns, | |
101 | use the default handler, which will not return. */ | |
102 | png_default_error(png_ptr, ""); | |
103 | } | |
104 | #endif /* PNG_ERROR_TEXT_SUPPORTED */ | |
105 | ||
106 | /* Utility to safely appends strings to a buffer. This never errors out so | |
107 | * error checking is not required in the caller. | |
108 | */ | |
109 | size_t | |
110 | png_safecat(png_charp buffer, size_t bufsize, size_t pos, | |
111 | png_const_charp string) | |
112 | { | |
113 | if (buffer != NULL && pos < bufsize) | |
114 | { | |
115 | if (string != NULL) | |
116 | while (*string != '\0' && pos < bufsize-1) | |
117 | buffer[pos++] = *string++; | |
118 | ||
119 | buffer[pos] = '\0'; | |
120 | } | |
121 | ||
122 | return pos; | |
123 | } | |
124 | ||
125 | #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED) | |
126 | /* Utility to dump an unsigned value into a buffer, given a start pointer and | |
127 | * and end pointer (which should point just *beyond* the end of the buffer!) | |
128 | * Returns the pointer to the start of the formatted string. | |
129 | */ | |
130 | png_charp | |
131 | png_format_number(png_const_charp start, png_charp end, int format, | |
132 | png_alloc_size_t number) | |
133 | { | |
134 | int count = 0; /* number of digits output */ | |
135 | int mincount = 1; /* minimum number required */ | |
136 | int output = 0; /* digit output (for the fixed point format) */ | |
137 | ||
138 | *--end = '\0'; | |
139 | ||
140 | /* This is written so that the loop always runs at least once, even with | |
141 | * number zero. | |
142 | */ | |
143 | while (end > start && (number != 0 || count < mincount)) | |
144 | { | |
145 | ||
146 | static const char digits[] = "0123456789ABCDEF"; | |
147 | ||
148 | switch (format) | |
149 | { | |
150 | case PNG_NUMBER_FORMAT_fixed: | |
151 | /* Needs five digits (the fraction) */ | |
152 | mincount = 5; | |
153 | if (output || number % 10 != 0) | |
154 | { | |
155 | *--end = digits[number % 10]; | |
156 | output = 1; | |
157 | } | |
158 | number /= 10; | |
159 | break; | |
160 | ||
161 | case PNG_NUMBER_FORMAT_02u: | |
162 | /* Expects at least 2 digits. */ | |
163 | mincount = 2; | |
164 | /* fall through */ | |
165 | ||
166 | case PNG_NUMBER_FORMAT_u: | |
167 | *--end = digits[number % 10]; | |
168 | number /= 10; | |
169 | break; | |
170 | ||
171 | case PNG_NUMBER_FORMAT_02x: | |
172 | /* This format expects at least two digits */ | |
173 | mincount = 2; | |
174 | /* fall through */ | |
175 | ||
176 | case PNG_NUMBER_FORMAT_x: | |
177 | *--end = digits[number & 0xf]; | |
178 | number >>= 4; | |
179 | break; | |
180 | ||
181 | default: /* an error */ | |
182 | number = 0; | |
183 | break; | |
184 | } | |
185 | ||
186 | /* Keep track of the number of digits added */ | |
187 | ++count; | |
188 | ||
189 | /* Float a fixed number here: */ | |
190 | if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start) | |
191 | { | |
192 | /* End of the fraction, but maybe nothing was output? In that case | |
193 | * drop the decimal point. If the number is a true zero handle that | |
194 | * here. | |
195 | */ | |
196 | if (output) | |
197 | *--end = '.'; | |
198 | else if (number == 0) /* and !output */ | |
199 | *--end = '0'; | |
200 | } | |
201 | } | |
202 | ||
203 | return end; | |
204 | } | |
205 | #endif | |
206 | ||
207 | #ifdef PNG_WARNINGS_SUPPORTED | |
208 | /* This function is called whenever there is a non-fatal error. This function | |
209 | * should not be changed. If there is a need to handle warnings differently, | |
210 | * you should supply a replacement warning function and use | |
211 | * png_set_error_fn() to replace the warning function at run-time. | |
212 | */ | |
213 | void PNGAPI | |
214 | png_warning(png_structp png_ptr, png_const_charp warning_message) | |
215 | { | |
216 | int offset = 0; | |
217 | if (png_ptr != NULL) | |
218 | { | |
219 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
220 | if (png_ptr->flags& | |
221 | (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) | |
222 | #endif | |
223 | { | |
224 | if (*warning_message == PNG_LITERAL_SHARP) | |
225 | { | |
226 | for (offset = 1; offset < 15; offset++) | |
227 | if (warning_message[offset] == ' ') | |
228 | break; | |
229 | } | |
230 | } | |
231 | } | |
232 | if (png_ptr != NULL && png_ptr->warning_fn != NULL) | |
233 | (*(png_ptr->warning_fn))(png_ptr, warning_message + offset); | |
234 | else | |
235 | png_default_warning(png_ptr, warning_message + offset); | |
236 | } | |
237 | ||
238 | /* These functions support 'formatted' warning messages with up to | |
239 | * PNG_WARNING_PARAMETER_COUNT parameters. In the format string the parameter | |
240 | * is introduced by @<number>, where 'number' starts at 1. This follows the | |
241 | * standard established by X/Open for internationalizable error messages. | |
242 | */ | |
243 | void | |
244 | png_warning_parameter(png_warning_parameters p, int number, | |
245 | png_const_charp string) | |
246 | { | |
247 | if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT) | |
248 | (void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string); | |
249 | } | |
250 | ||
251 | void | |
252 | png_warning_parameter_unsigned(png_warning_parameters p, int number, int format, | |
253 | png_alloc_size_t value) | |
254 | { | |
255 | char buffer[PNG_NUMBER_BUFFER_SIZE]; | |
256 | png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value)); | |
257 | } | |
258 | ||
259 | void | |
260 | png_warning_parameter_signed(png_warning_parameters p, int number, int format, | |
261 | png_int_32 value) | |
262 | { | |
263 | png_alloc_size_t u; | |
264 | png_charp str; | |
265 | char buffer[PNG_NUMBER_BUFFER_SIZE]; | |
266 | ||
267 | /* Avoid overflow by doing the negate in a png_alloc_size_t: */ | |
268 | u = (png_alloc_size_t)value; | |
269 | if (value < 0) | |
270 | u = ~u + 1; | |
271 | ||
272 | str = PNG_FORMAT_NUMBER(buffer, format, u); | |
273 | ||
274 | if (value < 0 && str > buffer) | |
275 | *--str = '-'; | |
276 | ||
277 | png_warning_parameter(p, number, str); | |
278 | } | |
279 | ||
280 | void | |
281 | png_formatted_warning(png_structp png_ptr, png_warning_parameters p, | |
282 | png_const_charp message) | |
283 | { | |
284 | /* The internal buffer is just 128 bytes - enough for all our messages, | |
285 | * overflow doesn't happen because this code checks! | |
286 | */ | |
287 | size_t i; | |
288 | char msg[128]; | |
289 | ||
290 | for (i=0; i<(sizeof msg)-1 && *message != '\0'; ++i) | |
291 | { | |
292 | if (*message == '@') | |
293 | { | |
294 | int parameter = -1; | |
295 | switch (*++message) | |
296 | { | |
297 | case '1': | |
298 | parameter = 0; | |
299 | break; | |
300 | ||
301 | case '2': | |
302 | parameter = 1; | |
303 | break; | |
304 | ||
305 | case '\0': | |
306 | continue; /* To break out of the for loop above. */ | |
307 | ||
308 | default: | |
309 | break; | |
310 | } | |
311 | ||
312 | if (parameter >= 0 && parameter < PNG_WARNING_PARAMETER_COUNT) | |
313 | { | |
314 | /* Append this parameter */ | |
315 | png_const_charp parm = p[parameter]; | |
316 | png_const_charp pend = p[parameter] + (sizeof p[parameter]); | |
317 | ||
318 | /* No need to copy the trailing '\0' here, but there is no guarantee | |
319 | * that parm[] has been initialized, so there is no guarantee of a | |
320 | * trailing '\0': | |
321 | */ | |
322 | for (; i<(sizeof msg)-1 && parm != '\0' && parm < pend; ++i) | |
323 | msg[i] = *parm++; | |
324 | ||
325 | ++message; | |
326 | continue; | |
327 | } | |
328 | ||
329 | /* else not a parameter and there is a character after the @ sign; just | |
330 | * copy that. | |
331 | */ | |
332 | } | |
333 | ||
334 | /* At this point *message can't be '\0', even in the bad parameter case | |
335 | * above where there is a lone '@' at the end of the message string. | |
336 | */ | |
337 | msg[i] = *message++; | |
338 | } | |
339 | ||
340 | /* i is always less than (sizeof msg), so: */ | |
341 | msg[i] = '\0'; | |
342 | ||
343 | /* And this is the formatted message: */ | |
344 | png_warning(png_ptr, msg); | |
345 | } | |
346 | #endif /* PNG_WARNINGS_SUPPORTED */ | |
347 | ||
348 | #ifdef PNG_BENIGN_ERRORS_SUPPORTED | |
349 | void PNGAPI | |
350 | png_benign_error(png_structp png_ptr, png_const_charp error_message) | |
351 | { | |
352 | if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) | |
353 | png_warning(png_ptr, error_message); | |
354 | else | |
355 | png_error(png_ptr, error_message); | |
356 | } | |
357 | #endif | |
358 | ||
359 | /* These utilities are used internally to build an error message that relates | |
360 | * to the current chunk. The chunk name comes from png_ptr->chunk_name, | |
361 | * this is used to prefix the message. The message is limited in length | |
362 | * to 63 bytes, the name characters are output as hex digits wrapped in [] | |
363 | * if the character is invalid. | |
364 | */ | |
365 | #define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) | |
366 | static PNG_CONST char png_digit[16] = { | |
367 | '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', | |
368 | 'A', 'B', 'C', 'D', 'E', 'F' | |
369 | }; | |
370 | ||
371 | #define PNG_MAX_ERROR_TEXT 64 | |
372 | #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED) | |
373 | static void /* PRIVATE */ | |
374 | png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp | |
375 | error_message) | |
376 | { | |
377 | png_uint_32 chunk_name = png_ptr->chunk_name; | |
378 | int iout = 0, ishift = 24; | |
379 | ||
380 | while (ishift >= 0) | |
381 | { | |
382 | int c = (int)(chunk_name >> ishift) & 0xff; | |
383 | ||
384 | ishift -= 8; | |
385 | if (isnonalpha(c)) | |
386 | { | |
387 | buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET; | |
388 | buffer[iout++] = png_digit[(c & 0xf0) >> 4]; | |
389 | buffer[iout++] = png_digit[c & 0x0f]; | |
390 | buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET; | |
391 | } | |
392 | ||
393 | else | |
394 | { | |
395 | buffer[iout++] = (char)c; | |
396 | } | |
397 | } | |
398 | ||
399 | if (error_message == NULL) | |
400 | buffer[iout] = '\0'; | |
401 | ||
402 | else | |
403 | { | |
404 | int iin = 0; | |
405 | ||
406 | buffer[iout++] = ':'; | |
407 | buffer[iout++] = ' '; | |
408 | ||
409 | while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0') | |
410 | buffer[iout++] = error_message[iin++]; | |
411 | ||
412 | /* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */ | |
413 | buffer[iout] = '\0'; | |
414 | } | |
415 | } | |
416 | #endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */ | |
417 | ||
418 | #if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED) | |
419 | PNG_FUNCTION(void,PNGAPI | |
420 | png_chunk_error,(png_structp png_ptr, png_const_charp error_message), | |
421 | PNG_NORETURN) | |
422 | { | |
423 | char msg[18+PNG_MAX_ERROR_TEXT]; | |
424 | if (png_ptr == NULL) | |
425 | png_error(png_ptr, error_message); | |
426 | ||
427 | else | |
428 | { | |
429 | png_format_buffer(png_ptr, msg, error_message); | |
430 | png_error(png_ptr, msg); | |
431 | } | |
432 | } | |
433 | #endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */ | |
434 | ||
435 | #ifdef PNG_WARNINGS_SUPPORTED | |
436 | void PNGAPI | |
437 | png_chunk_warning(png_structp png_ptr, png_const_charp warning_message) | |
438 | { | |
439 | char msg[18+PNG_MAX_ERROR_TEXT]; | |
440 | if (png_ptr == NULL) | |
441 | png_warning(png_ptr, warning_message); | |
442 | ||
443 | else | |
444 | { | |
445 | png_format_buffer(png_ptr, msg, warning_message); | |
446 | png_warning(png_ptr, msg); | |
447 | } | |
448 | } | |
449 | #endif /* PNG_WARNINGS_SUPPORTED */ | |
450 | ||
451 | #ifdef PNG_READ_SUPPORTED | |
452 | #ifdef PNG_BENIGN_ERRORS_SUPPORTED | |
453 | void PNGAPI | |
454 | png_chunk_benign_error(png_structp png_ptr, png_const_charp error_message) | |
455 | { | |
456 | if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) | |
457 | png_chunk_warning(png_ptr, error_message); | |
458 | ||
459 | else | |
460 | png_chunk_error(png_ptr, error_message); | |
461 | } | |
462 | #endif | |
463 | #endif /* PNG_READ_SUPPORTED */ | |
464 | ||
465 | #ifdef PNG_ERROR_TEXT_SUPPORTED | |
466 | #ifdef PNG_FLOATING_POINT_SUPPORTED | |
467 | PNG_FUNCTION(void, | |
468 | png_fixed_error,(png_structp png_ptr, png_const_charp name),PNG_NORETURN) | |
469 | { | |
470 | # define fixed_message "fixed point overflow in " | |
471 | # define fixed_message_ln ((sizeof fixed_message)-1) | |
472 | int iin; | |
473 | char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT]; | |
474 | png_memcpy(msg, fixed_message, fixed_message_ln); | |
475 | iin = 0; | |
476 | if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0) | |
477 | { | |
478 | msg[fixed_message_ln + iin] = name[iin]; | |
479 | ++iin; | |
480 | } | |
481 | msg[fixed_message_ln + iin] = 0; | |
482 | png_error(png_ptr, msg); | |
483 | } | |
484 | #endif | |
485 | #endif | |
486 | ||
487 | #ifdef PNG_SETJMP_SUPPORTED | |
488 | /* This API only exists if ANSI-C style error handling is used, | |
489 | * otherwise it is necessary for png_default_error to be overridden. | |
490 | */ | |
491 | jmp_buf* PNGAPI | |
492 | png_set_longjmp_fn(png_structp png_ptr, png_longjmp_ptr longjmp_fn, | |
493 | size_t jmp_buf_size) | |
494 | { | |
495 | if (png_ptr == NULL || jmp_buf_size != png_sizeof(jmp_buf)) | |
496 | return NULL; | |
497 | ||
498 | png_ptr->longjmp_fn = longjmp_fn; | |
499 | return &png_ptr->longjmp_buffer; | |
500 | } | |
501 | #endif | |
502 | ||
503 | /* This is the default error handling function. Note that replacements for | |
504 | * this function MUST NOT RETURN, or the program will likely crash. This | |
505 | * function is used by default, or if the program supplies NULL for the | |
506 | * error function pointer in png_set_error_fn(). | |
507 | */ | |
508 | static PNG_FUNCTION(void /* PRIVATE */, | |
509 | png_default_error,(png_structp png_ptr, png_const_charp error_message), | |
510 | PNG_NORETURN) | |
511 | { | |
512 | #ifdef PNG_CONSOLE_IO_SUPPORTED | |
513 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
514 | /* Check on NULL only added in 1.5.4 */ | |
515 | if (error_message != NULL && *error_message == PNG_LITERAL_SHARP) | |
516 | { | |
517 | /* Strip "#nnnn " from beginning of error message. */ | |
518 | int offset; | |
519 | char error_number[16]; | |
520 | for (offset = 0; offset<15; offset++) | |
521 | { | |
522 | error_number[offset] = error_message[offset + 1]; | |
523 | if (error_message[offset] == ' ') | |
524 | break; | |
525 | } | |
526 | ||
527 | if ((offset > 1) && (offset < 15)) | |
528 | { | |
529 | error_number[offset - 1] = '\0'; | |
530 | fprintf(stderr, "libpng error no. %s: %s", | |
531 | error_number, error_message + offset + 1); | |
532 | fprintf(stderr, PNG_STRING_NEWLINE); | |
533 | } | |
534 | ||
535 | else | |
536 | { | |
537 | fprintf(stderr, "libpng error: %s, offset=%d", | |
538 | error_message, offset); | |
539 | fprintf(stderr, PNG_STRING_NEWLINE); | |
540 | } | |
541 | } | |
542 | else | |
543 | #endif | |
544 | { | |
545 | fprintf(stderr, "libpng error: %s", error_message ? error_message : | |
546 | "undefined"); | |
547 | fprintf(stderr, PNG_STRING_NEWLINE); | |
548 | } | |
549 | #else | |
550 | PNG_UNUSED(error_message) /* Make compiler happy */ | |
551 | #endif | |
552 | png_longjmp(png_ptr, 1); | |
553 | } | |
554 | ||
555 | PNG_FUNCTION(void,PNGAPI | |
556 | png_longjmp,(png_structp png_ptr, int val),PNG_NORETURN) | |
557 | { | |
558 | #ifdef PNG_SETJMP_SUPPORTED | |
559 | if (png_ptr && png_ptr->longjmp_fn) | |
560 | { | |
561 | # ifdef USE_FAR_KEYWORD | |
562 | { | |
563 | jmp_buf tmp_jmpbuf; | |
564 | png_memcpy(tmp_jmpbuf, png_ptr->longjmp_buffer, png_sizeof(jmp_buf)); | |
565 | png_ptr->longjmp_fn(tmp_jmpbuf, val); | |
566 | } | |
567 | ||
568 | # else | |
569 | png_ptr->longjmp_fn(png_ptr->longjmp_buffer, val); | |
570 | # endif | |
571 | } | |
572 | #endif | |
573 | /* Here if not setjmp support or if png_ptr is null. */ | |
574 | PNG_ABORT(); | |
575 | } | |
576 | ||
577 | #ifdef PNG_WARNINGS_SUPPORTED | |
578 | /* This function is called when there is a warning, but the library thinks | |
579 | * it can continue anyway. Replacement functions don't have to do anything | |
580 | * here if you don't want them to. In the default configuration, png_ptr is | |
581 | * not used, but it is passed in case it may be useful. | |
582 | */ | |
583 | static void /* PRIVATE */ | |
584 | png_default_warning(png_structp png_ptr, png_const_charp warning_message) | |
585 | { | |
586 | #ifdef PNG_CONSOLE_IO_SUPPORTED | |
587 | # ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
588 | if (*warning_message == PNG_LITERAL_SHARP) | |
589 | { | |
590 | int offset; | |
591 | char warning_number[16]; | |
592 | for (offset = 0; offset < 15; offset++) | |
593 | { | |
594 | warning_number[offset] = warning_message[offset + 1]; | |
595 | if (warning_message[offset] == ' ') | |
596 | break; | |
597 | } | |
598 | ||
599 | if ((offset > 1) && (offset < 15)) | |
600 | { | |
601 | warning_number[offset + 1] = '\0'; | |
602 | fprintf(stderr, "libpng warning no. %s: %s", | |
603 | warning_number, warning_message + offset); | |
604 | fprintf(stderr, PNG_STRING_NEWLINE); | |
605 | } | |
606 | ||
607 | else | |
608 | { | |
609 | fprintf(stderr, "libpng warning: %s", | |
610 | warning_message); | |
611 | fprintf(stderr, PNG_STRING_NEWLINE); | |
612 | } | |
613 | } | |
614 | else | |
615 | # endif | |
616 | ||
617 | { | |
618 | fprintf(stderr, "libpng warning: %s", warning_message); | |
619 | fprintf(stderr, PNG_STRING_NEWLINE); | |
620 | } | |
621 | #else | |
622 | PNG_UNUSED(warning_message) /* Make compiler happy */ | |
623 | #endif | |
624 | PNG_UNUSED(png_ptr) /* Make compiler happy */ | |
625 | } | |
626 | #endif /* PNG_WARNINGS_SUPPORTED */ | |
627 | ||
628 | /* This function is called when the application wants to use another method | |
629 | * of handling errors and warnings. Note that the error function MUST NOT | |
630 | * return to the calling routine or serious problems will occur. The return | |
631 | * method used in the default routine calls longjmp(png_ptr->longjmp_buffer, 1) | |
632 | */ | |
633 | void PNGAPI | |
634 | png_set_error_fn(png_structp png_ptr, png_voidp error_ptr, | |
635 | png_error_ptr error_fn, png_error_ptr warning_fn) | |
636 | { | |
637 | if (png_ptr == NULL) | |
638 | return; | |
639 | ||
640 | png_ptr->error_ptr = error_ptr; | |
641 | png_ptr->error_fn = error_fn; | |
642 | #ifdef PNG_WARNINGS_SUPPORTED | |
643 | png_ptr->warning_fn = warning_fn; | |
644 | #else | |
645 | PNG_UNUSED(warning_fn) | |
646 | #endif | |
647 | } | |
648 | ||
649 | ||
650 | /* This function returns a pointer to the error_ptr associated with the user | |
651 | * functions. The application should free any memory associated with this | |
652 | * pointer before png_write_destroy and png_read_destroy are called. | |
653 | */ | |
654 | png_voidp PNGAPI | |
655 | png_get_error_ptr(png_const_structp png_ptr) | |
656 | { | |
657 | if (png_ptr == NULL) | |
658 | return NULL; | |
659 | ||
660 | return ((png_voidp)png_ptr->error_ptr); | |
661 | } | |
662 | ||
663 | ||
664 | #ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
665 | void PNGAPI | |
666 | png_set_strip_error_numbers(png_structp png_ptr, png_uint_32 strip_mode) | |
667 | { | |
668 | if (png_ptr != NULL) | |
669 | { | |
670 | png_ptr->flags &= | |
671 | ((~(PNG_FLAG_STRIP_ERROR_NUMBERS | | |
672 | PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode); | |
673 | } | |
674 | } | |
675 | #endif | |
676 | #endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ |