diff options
Diffstat (limited to 'libraries/irrlicht-1.8/source/Irrlicht/jpeglib/wrjpgcom.c')
-rw-r--r-- | libraries/irrlicht-1.8/source/Irrlicht/jpeglib/wrjpgcom.c | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/wrjpgcom.c b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/wrjpgcom.c new file mode 100644 index 0000000..7d10ee6 --- /dev/null +++ b/libraries/irrlicht-1.8/source/Irrlicht/jpeglib/wrjpgcom.c | |||
@@ -0,0 +1,583 @@ | |||
1 | /* | ||
2 | * wrjpgcom.c | ||
3 | * | ||
4 | * Copyright (C) 1994-1997, Thomas G. Lane. | ||
5 | * This file is part of the Independent JPEG Group's software. | ||
6 | * For conditions of distribution and use, see the accompanying README file. | ||
7 | * | ||
8 | * This file contains a very simple stand-alone application that inserts | ||
9 | * user-supplied text as a COM (comment) marker in a JFIF file. | ||
10 | * This may be useful as an example of the minimum logic needed to parse | ||
11 | * JPEG markers. | ||
12 | */ | ||
13 | |||
14 | #define JPEG_CJPEG_DJPEG /* to get the command-line config symbols */ | ||
15 | #include "jinclude.h" /* get auto-config symbols, <stdio.h> */ | ||
16 | |||
17 | #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc() */ | ||
18 | extern void * malloc (); | ||
19 | #endif | ||
20 | #include <ctype.h> /* to declare isupper(), tolower() */ | ||
21 | #ifdef USE_SETMODE | ||
22 | #include <fcntl.h> /* to declare setmode()'s parameter macros */ | ||
23 | /* If you have setmode() but not <io.h>, just delete this line: */ | ||
24 | #include <io.h> /* to declare setmode() */ | ||
25 | #endif | ||
26 | |||
27 | #ifdef USE_CCOMMAND /* command-line reader for Macintosh */ | ||
28 | #ifdef __MWERKS__ | ||
29 | #include <SIOUX.h> /* Metrowerks needs this */ | ||
30 | #include <console.h> /* ... and this */ | ||
31 | #endif | ||
32 | #ifdef THINK_C | ||
33 | #include <console.h> /* Think declares it here */ | ||
34 | #endif | ||
35 | #endif | ||
36 | |||
37 | #ifdef DONT_USE_B_MODE /* define mode parameters for fopen() */ | ||
38 | #define READ_BINARY "r" | ||
39 | #define WRITE_BINARY "w" | ||
40 | #else | ||
41 | #ifdef VMS /* VMS is very nonstandard */ | ||
42 | #define READ_BINARY "rb", "ctx=stm" | ||
43 | #define WRITE_BINARY "wb", "ctx=stm" | ||
44 | #else /* standard ANSI-compliant case */ | ||
45 | #define READ_BINARY "rb" | ||
46 | #define WRITE_BINARY "wb" | ||
47 | #endif | ||
48 | #endif | ||
49 | |||
50 | #ifndef EXIT_FAILURE /* define exit() codes if not provided */ | ||
51 | #define EXIT_FAILURE 1 | ||
52 | #endif | ||
53 | #ifndef EXIT_SUCCESS | ||
54 | #ifdef VMS | ||
55 | #define EXIT_SUCCESS 1 /* VMS is very nonstandard */ | ||
56 | #else | ||
57 | #define EXIT_SUCCESS 0 | ||
58 | #endif | ||
59 | #endif | ||
60 | |||
61 | /* Reduce this value if your malloc() can't allocate blocks up to 64K. | ||
62 | * On DOS, compiling in large model is usually a better solution. | ||
63 | */ | ||
64 | |||
65 | #ifndef MAX_COM_LENGTH | ||
66 | #define MAX_COM_LENGTH 65000L /* must be <= 65533 in any case */ | ||
67 | #endif | ||
68 | |||
69 | |||
70 | /* | ||
71 | * These macros are used to read the input file and write the output file. | ||
72 | * To reuse this code in another application, you might need to change these. | ||
73 | */ | ||
74 | |||
75 | static FILE * infile; /* input JPEG file */ | ||
76 | |||
77 | /* Return next input byte, or EOF if no more */ | ||
78 | #define NEXTBYTE() getc(infile) | ||
79 | |||
80 | static FILE * outfile; /* output JPEG file */ | ||
81 | |||
82 | /* Emit an output byte */ | ||
83 | #define PUTBYTE(x) putc((x), outfile) | ||
84 | |||
85 | |||
86 | /* Error exit handler */ | ||
87 | #define ERREXIT(msg) (fprintf(stderr, "%s\n", msg), exit(EXIT_FAILURE)) | ||
88 | |||
89 | |||
90 | /* Read one byte, testing for EOF */ | ||
91 | static int | ||
92 | read_1_byte (void) | ||
93 | { | ||
94 | int c; | ||
95 | |||
96 | c = NEXTBYTE(); | ||
97 | if (c == EOF) | ||
98 | ERREXIT("Premature EOF in JPEG file"); | ||
99 | return c; | ||
100 | } | ||
101 | |||
102 | /* Read 2 bytes, convert to unsigned int */ | ||
103 | /* All 2-byte quantities in JPEG markers are MSB first */ | ||
104 | static unsigned int | ||
105 | read_2_bytes (void) | ||
106 | { | ||
107 | int c1, c2; | ||
108 | |||
109 | c1 = NEXTBYTE(); | ||
110 | if (c1 == EOF) | ||
111 | ERREXIT("Premature EOF in JPEG file"); | ||
112 | c2 = NEXTBYTE(); | ||
113 | if (c2 == EOF) | ||
114 | ERREXIT("Premature EOF in JPEG file"); | ||
115 | return (((unsigned int) c1) << 8) + ((unsigned int) c2); | ||
116 | } | ||
117 | |||
118 | |||
119 | /* Routines to write data to output file */ | ||
120 | |||
121 | static void | ||
122 | write_1_byte (int c) | ||
123 | { | ||
124 | PUTBYTE(c); | ||
125 | } | ||
126 | |||
127 | static void | ||
128 | write_2_bytes (unsigned int val) | ||
129 | { | ||
130 | PUTBYTE((val >> 8) & 0xFF); | ||
131 | PUTBYTE(val & 0xFF); | ||
132 | } | ||
133 | |||
134 | static void | ||
135 | write_marker (int marker) | ||
136 | { | ||
137 | PUTBYTE(0xFF); | ||
138 | PUTBYTE(marker); | ||
139 | } | ||
140 | |||
141 | static void | ||
142 | copy_rest_of_file (void) | ||
143 | { | ||
144 | int c; | ||
145 | |||
146 | while ((c = NEXTBYTE()) != EOF) | ||
147 | PUTBYTE(c); | ||
148 | } | ||
149 | |||
150 | |||
151 | /* | ||
152 | * JPEG markers consist of one or more 0xFF bytes, followed by a marker | ||
153 | * code byte (which is not an FF). Here are the marker codes of interest | ||
154 | * in this program. (See jdmarker.c for a more complete list.) | ||
155 | */ | ||
156 | |||
157 | #define M_SOF0 0xC0 /* Start Of Frame N */ | ||
158 | #define M_SOF1 0xC1 /* N indicates which compression process */ | ||
159 | #define M_SOF2 0xC2 /* Only SOF0-SOF2 are now in common use */ | ||
160 | #define M_SOF3 0xC3 | ||
161 | #define M_SOF5 0xC5 /* NB: codes C4 and CC are NOT SOF markers */ | ||
162 | #define M_SOF6 0xC6 | ||
163 | #define M_SOF7 0xC7 | ||
164 | #define M_SOF9 0xC9 | ||
165 | #define M_SOF10 0xCA | ||
166 | #define M_SOF11 0xCB | ||
167 | #define M_SOF13 0xCD | ||
168 | #define M_SOF14 0xCE | ||
169 | #define M_SOF15 0xCF | ||
170 | #define M_SOI 0xD8 /* Start Of Image (beginning of datastream) */ | ||
171 | #define M_EOI 0xD9 /* End Of Image (end of datastream) */ | ||
172 | #define M_SOS 0xDA /* Start Of Scan (begins compressed data) */ | ||
173 | #define M_COM 0xFE /* COMment */ | ||
174 | |||
175 | |||
176 | /* | ||
177 | * Find the next JPEG marker and return its marker code. | ||
178 | * We expect at least one FF byte, possibly more if the compressor used FFs | ||
179 | * to pad the file. (Padding FFs will NOT be replicated in the output file.) | ||
180 | * There could also be non-FF garbage between markers. The treatment of such | ||
181 | * garbage is unspecified; we choose to skip over it but emit a warning msg. | ||
182 | * NB: this routine must not be used after seeing SOS marker, since it will | ||
183 | * not deal correctly with FF/00 sequences in the compressed image data... | ||
184 | */ | ||
185 | |||
186 | static int | ||
187 | next_marker (void) | ||
188 | { | ||
189 | int c; | ||
190 | int discarded_bytes = 0; | ||
191 | |||
192 | /* Find 0xFF byte; count and skip any non-FFs. */ | ||
193 | c = read_1_byte(); | ||
194 | while (c != 0xFF) { | ||
195 | discarded_bytes++; | ||
196 | c = read_1_byte(); | ||
197 | } | ||
198 | /* Get marker code byte, swallowing any duplicate FF bytes. Extra FFs | ||
199 | * are legal as pad bytes, so don't count them in discarded_bytes. | ||
200 | */ | ||
201 | do { | ||
202 | c = read_1_byte(); | ||
203 | } while (c == 0xFF); | ||
204 | |||
205 | if (discarded_bytes != 0) { | ||
206 | fprintf(stderr, "Warning: garbage data found in JPEG file\n"); | ||
207 | } | ||
208 | |||
209 | return c; | ||
210 | } | ||
211 | |||
212 | |||
213 | /* | ||
214 | * Read the initial marker, which should be SOI. | ||
215 | * For a JFIF file, the first two bytes of the file should be literally | ||
216 | * 0xFF M_SOI. To be more general, we could use next_marker, but if the | ||
217 | * input file weren't actually JPEG at all, next_marker might read the whole | ||
218 | * file and then return a misleading error message... | ||
219 | */ | ||
220 | |||
221 | static int | ||
222 | first_marker (void) | ||
223 | { | ||
224 | int c1, c2; | ||
225 | |||
226 | c1 = NEXTBYTE(); | ||
227 | c2 = NEXTBYTE(); | ||
228 | if (c1 != 0xFF || c2 != M_SOI) | ||
229 | ERREXIT("Not a JPEG file"); | ||
230 | return c2; | ||
231 | } | ||
232 | |||
233 | |||
234 | /* | ||
235 | * Most types of marker are followed by a variable-length parameter segment. | ||
236 | * This routine skips over the parameters for any marker we don't otherwise | ||
237 | * want to process. | ||
238 | * Note that we MUST skip the parameter segment explicitly in order not to | ||
239 | * be fooled by 0xFF bytes that might appear within the parameter segment; | ||
240 | * such bytes do NOT introduce new markers. | ||
241 | */ | ||
242 | |||
243 | static void | ||
244 | copy_variable (void) | ||
245 | /* Copy an unknown or uninteresting variable-length marker */ | ||
246 | { | ||
247 | unsigned int length; | ||
248 | |||
249 | /* Get the marker parameter length count */ | ||
250 | length = read_2_bytes(); | ||
251 | write_2_bytes(length); | ||
252 | /* Length includes itself, so must be at least 2 */ | ||
253 | if (length < 2) | ||
254 | ERREXIT("Erroneous JPEG marker length"); | ||
255 | length -= 2; | ||
256 | /* Skip over the remaining bytes */ | ||
257 | while (length > 0) { | ||
258 | write_1_byte(read_1_byte()); | ||
259 | length--; | ||
260 | } | ||
261 | } | ||
262 | |||
263 | static void | ||
264 | skip_variable (void) | ||
265 | /* Skip over an unknown or uninteresting variable-length marker */ | ||
266 | { | ||
267 | unsigned int length; | ||
268 | |||
269 | /* Get the marker parameter length count */ | ||
270 | length = read_2_bytes(); | ||
271 | /* Length includes itself, so must be at least 2 */ | ||
272 | if (length < 2) | ||
273 | ERREXIT("Erroneous JPEG marker length"); | ||
274 | length -= 2; | ||
275 | /* Skip over the remaining bytes */ | ||
276 | while (length > 0) { | ||
277 | (void) read_1_byte(); | ||
278 | length--; | ||
279 | } | ||
280 | } | ||
281 | |||
282 | |||
283 | /* | ||
284 | * Parse the marker stream until SOFn or EOI is seen; | ||
285 | * copy data to output, but discard COM markers unless keep_COM is true. | ||
286 | */ | ||
287 | |||
288 | static int | ||
289 | scan_JPEG_header (int keep_COM) | ||
290 | { | ||
291 | int marker; | ||
292 | |||
293 | /* Expect SOI at start of file */ | ||
294 | if (first_marker() != M_SOI) | ||
295 | ERREXIT("Expected SOI marker first"); | ||
296 | write_marker(M_SOI); | ||
297 | |||
298 | /* Scan miscellaneous markers until we reach SOFn. */ | ||
299 | for (;;) { | ||
300 | marker = next_marker(); | ||
301 | switch (marker) { | ||
302 | /* Note that marker codes 0xC4, 0xC8, 0xCC are not, and must not be, | ||
303 | * treated as SOFn. C4 in particular is actually DHT. | ||
304 | */ | ||
305 | case M_SOF0: /* Baseline */ | ||
306 | case M_SOF1: /* Extended sequential, Huffman */ | ||
307 | case M_SOF2: /* Progressive, Huffman */ | ||
308 | case M_SOF3: /* Lossless, Huffman */ | ||
309 | case M_SOF5: /* Differential sequential, Huffman */ | ||
310 | case M_SOF6: /* Differential progressive, Huffman */ | ||
311 | case M_SOF7: /* Differential lossless, Huffman */ | ||
312 | case M_SOF9: /* Extended sequential, arithmetic */ | ||
313 | case M_SOF10: /* Progressive, arithmetic */ | ||
314 | case M_SOF11: /* Lossless, arithmetic */ | ||
315 | case M_SOF13: /* Differential sequential, arithmetic */ | ||
316 | case M_SOF14: /* Differential progressive, arithmetic */ | ||
317 | case M_SOF15: /* Differential lossless, arithmetic */ | ||
318 | return marker; | ||
319 | |||
320 | case M_SOS: /* should not see compressed data before SOF */ | ||
321 | ERREXIT("SOS without prior SOFn"); | ||
322 | break; | ||
323 | |||
324 | case M_EOI: /* in case it's a tables-only JPEG stream */ | ||
325 | return marker; | ||
326 | |||
327 | case M_COM: /* Existing COM: conditionally discard */ | ||
328 | if (keep_COM) { | ||
329 | write_marker(marker); | ||
330 | copy_variable(); | ||
331 | } else { | ||
332 | skip_variable(); | ||
333 | } | ||
334 | break; | ||
335 | |||
336 | default: /* Anything else just gets copied */ | ||
337 | write_marker(marker); | ||
338 | copy_variable(); /* we assume it has a parameter count... */ | ||
339 | break; | ||
340 | } | ||
341 | } /* end loop */ | ||
342 | } | ||
343 | |||
344 | |||
345 | /* Command line parsing code */ | ||
346 | |||
347 | static const char * progname; /* program name for error messages */ | ||
348 | |||
349 | |||
350 | static void | ||
351 | usage (void) | ||
352 | /* complain about bad command line */ | ||
353 | { | ||
354 | fprintf(stderr, "wrjpgcom inserts a textual comment in a JPEG file.\n"); | ||
355 | fprintf(stderr, "You can add to or replace any existing comment(s).\n"); | ||
356 | |||
357 | fprintf(stderr, "Usage: %s [switches] ", progname); | ||
358 | #ifdef TWO_FILE_COMMANDLINE | ||
359 | fprintf(stderr, "inputfile outputfile\n"); | ||
360 | #else | ||
361 | fprintf(stderr, "[inputfile]\n"); | ||
362 | #endif | ||
363 | |||
364 | fprintf(stderr, "Switches (names may be abbreviated):\n"); | ||
365 | fprintf(stderr, " -replace Delete any existing comments\n"); | ||
366 | fprintf(stderr, " -comment \"text\" Insert comment with given text\n"); | ||
367 | fprintf(stderr, " -cfile name Read comment from named file\n"); | ||
368 | fprintf(stderr, "Notice that you must put quotes around the comment text\n"); | ||
369 | fprintf(stderr, "when you use -comment.\n"); | ||
370 | fprintf(stderr, "If you do not give either -comment or -cfile on the command line,\n"); | ||
371 | fprintf(stderr, "then the comment text is read from standard input.\n"); | ||
372 | fprintf(stderr, "It can be multiple lines, up to %u characters total.\n", | ||
373 | (unsigned int) MAX_COM_LENGTH); | ||
374 | #ifndef TWO_FILE_COMMANDLINE | ||
375 | fprintf(stderr, "You must specify an input JPEG file name when supplying\n"); | ||
376 | fprintf(stderr, "comment text from standard input.\n"); | ||
377 | #endif | ||
378 | |||
379 | exit(EXIT_FAILURE); | ||
380 | } | ||
381 | |||
382 | |||
383 | static int | ||
384 | keymatch (char * arg, const char * keyword, int minchars) | ||
385 | /* Case-insensitive matching of (possibly abbreviated) keyword switches. */ | ||
386 | /* keyword is the constant keyword (must be lower case already), */ | ||
387 | /* minchars is length of minimum legal abbreviation. */ | ||
388 | { | ||
389 | register int ca, ck; | ||
390 | register int nmatched = 0; | ||
391 | |||
392 | while ((ca = *arg++) != '\0') { | ||
393 | if ((ck = *keyword++) == '\0') | ||
394 | return 0; /* arg longer than keyword, no good */ | ||
395 | if (isupper(ca)) /* force arg to lcase (assume ck is already) */ | ||
396 | ca = tolower(ca); | ||
397 | if (ca != ck) | ||
398 | return 0; /* no good */ | ||
399 | nmatched++; /* count matched characters */ | ||
400 | } | ||
401 | /* reached end of argument; fail if it's too short for unique abbrev */ | ||
402 | if (nmatched < minchars) | ||
403 | return 0; | ||
404 | return 1; /* A-OK */ | ||
405 | } | ||
406 | |||
407 | |||
408 | /* | ||
409 | * The main program. | ||
410 | */ | ||
411 | |||
412 | int | ||
413 | main (int argc, char **argv) | ||
414 | { | ||
415 | int argn; | ||
416 | char * arg; | ||
417 | int keep_COM = 1; | ||
418 | char * comment_arg = NULL; | ||
419 | FILE * comment_file = NULL; | ||
420 | unsigned int comment_length = 0; | ||
421 | int marker; | ||
422 | |||
423 | /* On Mac, fetch a command line. */ | ||
424 | #ifdef USE_CCOMMAND | ||
425 | argc = ccommand(&argv); | ||
426 | #endif | ||
427 | |||
428 | progname = argv[0]; | ||
429 | if (progname == NULL || progname[0] == 0) | ||
430 | progname = "wrjpgcom"; /* in case C library doesn't provide it */ | ||
431 | |||
432 | /* Parse switches, if any */ | ||
433 | for (argn = 1; argn < argc; argn++) { | ||
434 | arg = argv[argn]; | ||
435 | if (arg[0] != '-') | ||
436 | break; /* not switch, must be file name */ | ||
437 | arg++; /* advance over '-' */ | ||
438 | if (keymatch(arg, "replace", 1)) { | ||
439 | keep_COM = 0; | ||
440 | } else if (keymatch(arg, "cfile", 2)) { | ||
441 | if (++argn >= argc) usage(); | ||
442 | if ((comment_file = fopen(argv[argn], "r")) == NULL) { | ||
443 | fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]); | ||
444 | exit(EXIT_FAILURE); | ||
445 | } | ||
446 | } else if (keymatch(arg, "comment", 1)) { | ||
447 | if (++argn >= argc) usage(); | ||
448 | comment_arg = argv[argn]; | ||
449 | /* If the comment text starts with '"', then we are probably running | ||
450 | * under MS-DOG and must parse out the quoted string ourselves. Sigh. | ||
451 | */ | ||
452 | if (comment_arg[0] == '"') { | ||
453 | comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH); | ||
454 | if (comment_arg == NULL) | ||
455 | ERREXIT("Insufficient memory"); | ||
456 | strcpy(comment_arg, argv[argn]+1); | ||
457 | for (;;) { | ||
458 | comment_length = (unsigned int) strlen(comment_arg); | ||
459 | if (comment_length > 0 && comment_arg[comment_length-1] == '"') { | ||
460 | comment_arg[comment_length-1] = '\0'; /* zap terminating quote */ | ||
461 | break; | ||
462 | } | ||
463 | if (++argn >= argc) | ||
464 | ERREXIT("Missing ending quote mark"); | ||
465 | strcat(comment_arg, " "); | ||
466 | strcat(comment_arg, argv[argn]); | ||
467 | } | ||
468 | } | ||
469 | comment_length = (unsigned int) strlen(comment_arg); | ||
470 | } else | ||
471 | usage(); | ||
472 | } | ||
473 | |||
474 | /* Cannot use both -comment and -cfile. */ | ||
475 | if (comment_arg != NULL && comment_file != NULL) | ||
476 | usage(); | ||
477 | /* If there is neither -comment nor -cfile, we will read the comment text | ||
478 | * from stdin; in this case there MUST be an input JPEG file name. | ||
479 | */ | ||
480 | if (comment_arg == NULL && comment_file == NULL && argn >= argc) | ||
481 | usage(); | ||
482 | |||
483 | /* Open the input file. */ | ||
484 | if (argn < argc) { | ||
485 | if ((infile = fopen(argv[argn], READ_BINARY)) == NULL) { | ||
486 | fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]); | ||
487 | exit(EXIT_FAILURE); | ||
488 | } | ||
489 | } else { | ||
490 | /* default input file is stdin */ | ||
491 | #ifdef USE_SETMODE /* need to hack file mode? */ | ||
492 | setmode(fileno(stdin), O_BINARY); | ||
493 | #endif | ||
494 | #ifdef USE_FDOPEN /* need to re-open in binary mode? */ | ||
495 | if ((infile = fdopen(fileno(stdin), READ_BINARY)) == NULL) { | ||
496 | fprintf(stderr, "%s: can't open stdin\n", progname); | ||
497 | exit(EXIT_FAILURE); | ||
498 | } | ||
499 | #else | ||
500 | infile = stdin; | ||
501 | #endif | ||
502 | } | ||
503 | |||
504 | /* Open the output file. */ | ||
505 | #ifdef TWO_FILE_COMMANDLINE | ||
506 | /* Must have explicit output file name */ | ||
507 | if (argn != argc-2) { | ||
508 | fprintf(stderr, "%s: must name one input and one output file\n", | ||
509 | progname); | ||
510 | usage(); | ||
511 | } | ||
512 | if ((outfile = fopen(argv[argn+1], WRITE_BINARY)) == NULL) { | ||
513 | fprintf(stderr, "%s: can't open %s\n", progname, argv[argn+1]); | ||
514 | exit(EXIT_FAILURE); | ||
515 | } | ||
516 | #else | ||
517 | /* Unix style: expect zero or one file name */ | ||
518 | if (argn < argc-1) { | ||
519 | fprintf(stderr, "%s: only one input file\n", progname); | ||
520 | usage(); | ||
521 | } | ||
522 | /* default output file is stdout */ | ||
523 | #ifdef USE_SETMODE /* need to hack file mode? */ | ||
524 | setmode(fileno(stdout), O_BINARY); | ||
525 | #endif | ||
526 | #ifdef USE_FDOPEN /* need to re-open in binary mode? */ | ||
527 | if ((outfile = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) { | ||
528 | fprintf(stderr, "%s: can't open stdout\n", progname); | ||
529 | exit(EXIT_FAILURE); | ||
530 | } | ||
531 | #else | ||
532 | outfile = stdout; | ||
533 | #endif | ||
534 | #endif /* TWO_FILE_COMMANDLINE */ | ||
535 | |||
536 | /* Collect comment text from comment_file or stdin, if necessary */ | ||
537 | if (comment_arg == NULL) { | ||
538 | FILE * src_file; | ||
539 | int c; | ||
540 | |||
541 | comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH); | ||
542 | if (comment_arg == NULL) | ||
543 | ERREXIT("Insufficient memory"); | ||
544 | comment_length = 0; | ||
545 | src_file = (comment_file != NULL ? comment_file : stdin); | ||
546 | while ((c = getc(src_file)) != EOF) { | ||
547 | if (comment_length >= (unsigned int) MAX_COM_LENGTH) { | ||
548 | fprintf(stderr, "Comment text may not exceed %u bytes\n", | ||
549 | (unsigned int) MAX_COM_LENGTH); | ||
550 | exit(EXIT_FAILURE); | ||
551 | } | ||
552 | comment_arg[comment_length++] = (char) c; | ||
553 | } | ||
554 | if (comment_file != NULL) | ||
555 | fclose(comment_file); | ||
556 | } | ||
557 | |||
558 | /* Copy JPEG headers until SOFn marker; | ||
559 | * we will insert the new comment marker just before SOFn. | ||
560 | * This (a) causes the new comment to appear after, rather than before, | ||
561 | * existing comments; and (b) ensures that comments come after any JFIF | ||
562 | * or JFXX markers, as required by the JFIF specification. | ||
563 | */ | ||
564 | marker = scan_JPEG_header(keep_COM); | ||
565 | /* Insert the new COM marker, but only if nonempty text has been supplied */ | ||
566 | if (comment_length > 0) { | ||
567 | write_marker(M_COM); | ||
568 | write_2_bytes(comment_length + 2); | ||
569 | while (comment_length > 0) { | ||
570 | write_1_byte(*comment_arg++); | ||
571 | comment_length--; | ||
572 | } | ||
573 | } | ||
574 | /* Duplicate the remainder of the source file. | ||
575 | * Note that any COM markers occuring after SOF will not be touched. | ||
576 | */ | ||
577 | write_marker(marker); | ||
578 | copy_rest_of_file(); | ||
579 | |||
580 | /* All done. */ | ||
581 | exit(EXIT_SUCCESS); | ||
582 | return 0; /* suppress no-return-value warnings */ | ||
583 | } | ||