compiler/libjpeg/test/wrjpgcom.c

   1 /*
   2     $Id$
   3 */
   4
   5 /*
   6  * wrjpgcom.c
   7  *
   8  * Copyright (C) 1994-1997, Thomas G. Lane.
   9  * This file is part of the Independent JPEG Group's software.
  10  * For conditions of distribution and use, see the accompanying README file.
  11  *
  12  * This file contains a very simple stand-alone application that inserts
  13  * user-supplied text as a COM (comment) marker in a JFIF file.
  14  * This may be useful as an example of the minimum logic needed to parse
  15  * JPEG markers.
  16  */
  17
  18 #define JPEG_CJPEG_DJPEG        /* to get the command-line config symbols */
  19 #include "jinclude.h"           /* get auto-config symbols, <stdio.h> */
  20
  21 #ifndef HAVE_STDLIB_H           /* <stdlib.h> should declare malloc() */
  22 extern void * malloc ();
  23 #endif
  24 #include <ctype.h>              /* to declare isupper(), tolower() */
  25 #ifdef USE_SETMODE
  26 #include <fcntl.h>              /* to declare setmode()'s parameter macros */
  27 /* If you have setmode() but not <io.h>, just delete this line: */
  28 #include <io.h>                 /* to declare setmode() */
  29 #endif
  30
  31 #ifdef USE_CCOMMAND             /* command-line reader for Macintosh */
  32 #ifdef __MWERKS__
  33 #include <SIOUX.h>              /* Metrowerks needs this */
  34 #include <console.h>            /* ... and this */
  35 #endif
  36 #ifdef THINK_C
  37 #include <console.h>            /* Think declares it here */
  38 #endif
  39 #endif
  40
  41 #ifdef DONT_USE_B_MODE          /* define mode parameters for fopen() */
  42 #define READ_BINARY     "r"
  43 #define WRITE_BINARY    "w"
  44 #else
  45 #ifdef VMS                      /* VMS is very nonstandard */
  46 #define READ_BINARY     "rb", "ctx=stm"
  47 #define WRITE_BINARY    "wb", "ctx=stm"
  48 #else                           /* standard ANSI-compliant case */
  49 #define READ_BINARY     "rb"
  50 #define WRITE_BINARY    "wb"
  51 #endif
  52 #endif
  53
  54 #ifndef EXIT_FAILURE            /* define exit() codes if not provided */
  55 #define EXIT_FAILURE  1
  56 #endif
  57 #ifndef EXIT_SUCCESS
  58 #ifdef VMS
  59 #define EXIT_SUCCESS  1         /* VMS is very nonstandard */
  60 #else
  61 #define EXIT_SUCCESS  0
  62 #endif
  63 #endif
  64
  65 /* Reduce this value if your malloc() can't allocate blocks up to 64K.
  66  * On DOS, compiling in large model is usually a better solution.
  67  */
  68
  69 #ifndef MAX_COM_LENGTH
  70 #define MAX_COM_LENGTH 65000L   /* must be <= 65533 in any case */
  71 #endif
  72
  73
  74 /*
  75  * These macros are used to read the input file and write the output file.
  76  * To reuse this code in another application, you might need to change these.
  77  */
  78
  79 static FILE * infile;           /* input JPEG file */
  80
  81 /* Return next input byte, or EOF if no more */
  82 #define NEXTBYTE()  getc(infile)
  83
  84 static FILE * outfile;          /* output JPEG file */
  85
  86 /* Emit an output byte */
  87 #define PUTBYTE(x)  putc((x), outfile)
  88
  89
  90 /* Error exit handler */
  91 #define ERREXIT(msg)  (fprintf(stderr, "%s\n", msg), exit(EXIT_FAILURE))
  92
  93
  94 /* Read one byte, testing for EOF */
  95 static int
  96 read_1_byte (void)
  97 {
  98   int c;
  99
 100   c = NEXTBYTE();
 101   if (c == EOF)
 102     ERREXIT("Premature EOF in JPEG file");
 103   return c;
 104 }
 105
 106 /* Read 2 bytes, convert to unsigned int */
 107 /* All 2-byte quantities in JPEG markers are MSB first */
 108 static unsigned int
 109 read_2_bytes (void)
 110 {
 111   int c1, c2;
 112
 113   c1 = NEXTBYTE();
 114   if (c1 == EOF)
 115     ERREXIT("Premature EOF in JPEG file");
 116   c2 = NEXTBYTE();
 117   if (c2 == EOF)
 118     ERREXIT("Premature EOF in JPEG file");
 119   return (((unsigned int) c1) << 8) + ((unsigned int) c2);
 120 }
 121
 122
 123 /* Routines to write data to output file */
 124
 125 static void
 126 write_1_byte (int c)
 127 {
 128   PUTBYTE(c);
 129 }
 130
 131 static void
 132 write_2_bytes (unsigned int val)
 133 {
 134   PUTBYTE((val >> 8) & 0xFF);
 135   PUTBYTE(val & 0xFF);
 136 }
 137
 138 static void
 139 write_marker (int marker)
 140 {
 141   PUTBYTE(0xFF);
 142   PUTBYTE(marker);
 143 }
 144
 145 static void
 146 copy_rest_of_file (void)
 147 {
 148   int c;
 149
 150   while ((c = NEXTBYTE()) != EOF)
 151     PUTBYTE(c);
 152 }
 153
 154
 155 /*
 156  * JPEG markers consist of one or more 0xFF bytes, followed by a marker
 157  * code byte (which is not an FF).  Here are the marker codes of interest
 158  * in this program.  (See jdmarker.c for a more complete list.)
 159  */
 160
 161 #define M_SOF0  0xC0            /* Start Of Frame N */
 162 #define M_SOF1  0xC1            /* N indicates which compression process */
 163 #define M_SOF2  0xC2            /* Only SOF0-SOF2 are now in common use */
 164 #define M_SOF3  0xC3
 165 #define M_SOF5  0xC5            /* NB: codes C4 and CC are NOT SOF markers */
 166 #define M_SOF6  0xC6
 167 #define M_SOF7  0xC7
 168 #define M_SOF9  0xC9
 169 #define M_SOF10 0xCA
 170 #define M_SOF11 0xCB
 171 #define M_SOF13 0xCD
 172 #define M_SOF14 0xCE
 173 #define M_SOF15 0xCF
 174 #define M_SOI   0xD8            /* Start Of Image (beginning of datastream) */
 175 #define M_EOI   0xD9            /* End Of Image (end of datastream) */
 176 #define M_SOS   0xDA            /* Start Of Scan (begins compressed data) */
 177 #define M_COM   0xFE            /* COMment */
 178
 179
 180 /*
 181  * Find the next JPEG marker and return its marker code.
 182  * We expect at least one FF byte, possibly more if the compressor used FFs
 183  * to pad the file.  (Padding FFs will NOT be replicated in the output file.)
 184  * There could also be non-FF garbage between markers.  The treatment of such
 185  * garbage is unspecified; we choose to skip over it but emit a warning msg.
 186  * NB: this routine must not be used after seeing SOS marker, since it will
 187  * not deal correctly with FF/00 sequences in the compressed image data...
 188  */
 189
 190 static int
 191 next_marker (void)
 192 {
 193   int c;
 194   int discarded_bytes = 0;
 195
 196   /* Find 0xFF byte; count and skip any non-FFs. */
 197   c = read_1_byte();
 198   while (c != 0xFF) {
 199     discarded_bytes++;
 200     c = read_1_byte();
 201   }
 202   /* Get marker code byte, swallowing any duplicate FF bytes.  Extra FFs
 203    * are legal as pad bytes, so don't count them in discarded_bytes.
 204    */
 205   do {
 206     c = read_1_byte();
 207   } while (c == 0xFF);
 208
 209   if (discarded_bytes != 0) {
 210     fprintf(stderr, "Warning: garbage data found in JPEG file\n");
 211   }
 212
 213   return c;
 214 }
 215
 216
 217 /*
 218  * Read the initial marker, which should be SOI.
 219  * For a JFIF file, the first two bytes of the file should be literally
 220  * 0xFF M_SOI.  To be more general, we could use next_marker, but if the
 221  * input file weren't actually JPEG at all, next_marker might read the whole
 222  * file and then return a misleading error message...
 223  */
 224
 225 static int
 226 first_marker (void)
 227 {
 228   int c1, c2;
 229
 230   c1 = NEXTBYTE();
 231   c2 = NEXTBYTE();
 232   if (c1 != 0xFF || c2 != M_SOI)
 233     ERREXIT("Not a JPEG file");
 234   return c2;
 235 }
 236
 237
 238 /*
 239  * Most types of marker are followed by a variable-length parameter segment.
 240  * This routine skips over the parameters for any marker we don't otherwise
 241  * want to process.
 242  * Note that we MUST skip the parameter segment explicitly in order not to
 243  * be fooled by 0xFF bytes that might appear within the parameter segment;
 244  * such bytes do NOT introduce new markers.
 245  */
 246
 247 static void
 248 copy_variable (void)
 249 /* Copy an unknown or uninteresting variable-length marker */
 250 {
 251   unsigned int length;
 252
 253   /* Get the marker parameter length count */
 254   length = read_2_bytes();
 255   write_2_bytes(length);
 256   /* Length includes itself, so must be at least 2 */
 257   if (length < 2)
 258     ERREXIT("Erroneous JPEG marker length");
 259   length -= 2;
 260   /* Skip over the remaining bytes */
 261   while (length > 0) {
 262     write_1_byte(read_1_byte());
 263     length--;
 264   }
 265 }
 266
 267 static void
 268 skip_variable (void)
 269 /* Skip over an unknown or uninteresting variable-length marker */
 270 {
 271   unsigned int length;
 272
 273   /* Get the marker parameter length count */
 274   length = read_2_bytes();
 275   /* Length includes itself, so must be at least 2 */
 276   if (length < 2)
 277     ERREXIT("Erroneous JPEG marker length");
 278   length -= 2;
 279   /* Skip over the remaining bytes */
 280   while (length > 0) {
 281     (void) read_1_byte();
 282     length--;
 283   }
 284 }
 285
 286
 287 /*
 288  * Parse the marker stream until SOFn or EOI is seen;
 289  * copy data to output, but discard COM markers unless keep_COM is true.
 290  */
 291
 292 static int
 293 scan_JPEG_header (int keep_COM)
 294 {
 295   int marker;
 296
 297   /* Expect SOI at start of file */
 298   if (first_marker() != M_SOI)
 299     ERREXIT("Expected SOI marker first");
 300   write_marker(M_SOI);
 301
 302   /* Scan miscellaneous markers until we reach SOFn. */
 303   for (;;) {
 304     marker = next_marker();
 305     switch (marker) {
 306       /* Note that marker codes 0xC4, 0xC8, 0xCC are not, and must not be,
 307        * treated as SOFn.  C4 in particular is actually DHT.
 308        */
 309     case M_SOF0:                /* Baseline */
 310     case M_SOF1:                /* Extended sequential, Huffman */
 311     case M_SOF2:                /* Progressive, Huffman */
 312     case M_SOF3:                /* Lossless, Huffman */
 313     case M_SOF5:                /* Differential sequential, Huffman */
 314     case M_SOF6:                /* Differential progressive, Huffman */
 315     case M_SOF7:                /* Differential lossless, Huffman */
 316     case M_SOF9:                /* Extended sequential, arithmetic */
 317     case M_SOF10:               /* Progressive, arithmetic */
 318     case M_SOF11:               /* Lossless, arithmetic */
 319     case M_SOF13:               /* Differential sequential, arithmetic */
 320     case M_SOF14:               /* Differential progressive, arithmetic */
 321     case M_SOF15:               /* Differential lossless, arithmetic */
 322       return marker;
 323
 324     case M_SOS:                 /* should not see compressed data before SOF */
 325       ERREXIT("SOS without prior SOFn");
 326       break;
 327
 328     case M_EOI:                 /* in case it's a tables-only JPEG stream */
 329       return marker;
 330
 331     case M_COM:                 /* Existing COM: conditionally discard */
 332       if (keep_COM) {
 333         write_marker(marker);
 334         copy_variable();
 335       } else {
 336         skip_variable();
 337       }
 338       break;
 339
 340     default:                    /* Anything else just gets copied */
 341       write_marker(marker);
 342       copy_variable();          /* we assume it has a parameter count... */
 343       break;
 344     }
 345   } /* end loop */
 346 }
 347
 348
 349 /* Command line parsing code */
 350
 351 static const char * progname;   /* program name for error messages */
 352
 353
 354 static void
 355 usage (void)
 356 /* complain about bad command line */
 357 {
 358   fprintf(stderr, "wrjpgcom inserts a textual comment in a JPEG file.\n");
 359   fprintf(stderr, "You can add to or replace any existing comment(s).\n");
 360
 361   fprintf(stderr, "Usage: %s [switches] ", progname);
 362 #ifdef TWO_FILE_COMMANDLINE
 363   fprintf(stderr, "inputfile outputfile\n");
 364 #else
 365   fprintf(stderr, "[inputfile]\n");
 366 #endif
 367
 368   fprintf(stderr, "Switches (names may be abbreviated):\n");
 369   fprintf(stderr, "  -replace         Delete any existing comments\n");
 370   fprintf(stderr, "  -comment \"text\"  Insert comment with given text\n");
 371   fprintf(stderr, "  -cfile name      Read comment from named file\n");
 372   fprintf(stderr, "Notice that you must put quotes around the comment text\n");
 373   fprintf(stderr, "when you use -comment.\n");
 374   fprintf(stderr, "If you do not give either -comment or -cfile on the command line,\n");
 375   fprintf(stderr, "then the comment text is read from standard input.\n");
 376   fprintf(stderr, "It can be multiple lines, up to %u characters total.\n",
 377           (unsigned int) MAX_COM_LENGTH);
 378 #ifndef TWO_FILE_COMMANDLINE
 379   fprintf(stderr, "You must specify an input JPEG file name when supplying\n");
 380   fprintf(stderr, "comment text from standard input.\n");
 381 #endif
 382
 383   exit(EXIT_FAILURE);
 384 }
 385
 386
 387 static int
 388 keymatch (char * arg, const char * keyword, int minchars)
 389 /* Case-insensitive matching of (possibly abbreviated) keyword switches. */
 390 /* keyword is the constant keyword (must be lower case already), */
 391 /* minchars is length of minimum legal abbreviation. */
 392 {
 393   register int ca, ck;
 394   register int nmatched = 0;
 395
 396   while ((ca = *arg++) != '\0') {
 397     if ((ck = *keyword++) == '\0')
 398       return 0;                 /* arg longer than keyword, no good */
 399     if (isupper(ca))            /* force arg to lcase (assume ck is already) */
 400       ca = tolower(ca);
 401     if (ca != ck)
 402       return 0;                 /* no good */
 403     nmatched++;                 /* count matched characters */
 404   }
 405   /* reached end of argument; fail if it's too short for unique abbrev */
 406   if (nmatched < minchars)
 407     return 0;
 408   return 1;                     /* A-OK */
 409 }
 410
 411
 412 /*
 413  * The main program.
 414  */
 415
 416 int
 417 main (int argc, char **argv)
 418 {
 419   int argn;
 420   char * arg;
 421   int keep_COM = 1;
 422   char * comment_arg = NULL;
 423   FILE * comment_file = NULL;
 424   unsigned int comment_length = 0;
 425   int marker;
 426
 427   /* On Mac, fetch a command line. */
 428 #ifdef USE_CCOMMAND
 429   argc = ccommand(&argv);
 430 #endif
 431
 432   progname = argv[0];
 433   if (progname == NULL || progname[0] == 0)
 434     progname = "wrjpgcom";      /* in case C library doesn't provide it */
 435
 436   /* Parse switches, if any */
 437   for (argn = 1; argn < argc; argn++) {
 438     arg = argv[argn];
 439     if (arg[0] != '-')
 440       break;                    /* not switch, must be file name */
 441     arg++;                      /* advance over '-' */
 442     if (keymatch(arg, "replace", 1)) {
 443       keep_COM = 0;
 444     } else if (keymatch(arg, "cfile", 2)) {
 445       if (++argn >= argc) usage();
 446       if ((comment_file = fopen(argv[argn], "r")) == NULL) {
 447         fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
 448         exit(EXIT_FAILURE);
 449       }
 450     } else if (keymatch(arg, "comment", 1)) {
 451       if (++argn >= argc) usage();
 452       comment_arg = argv[argn];
 453       /* If the comment text starts with '"', then we are probably running
 454        * under MS-DOG and must parse out the quoted string ourselves.  Sigh.
 455        */
 456       if (comment_arg[0] == '"') {
 457         comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH);
 458         if (comment_arg == NULL)
 459           ERREXIT("Insufficient memory");
 460         strcpy(comment_arg, argv[argn]+1);
 461         for (;;) {
 462           comment_length = (unsigned int) strlen(comment_arg);
 463           if (comment_length > 0 && comment_arg[comment_length-1] == '"') {
 464             comment_arg[comment_length-1] = '\0'; /* zap terminating quote */
 465             break;
 466           }
 467           if (++argn >= argc)
 468             ERREXIT("Missing ending quote mark");
 469           strcat(comment_arg, " ");
 470           strcat(comment_arg, argv[argn]);
 471         }
 472       }
 473       comment_length = (unsigned int) strlen(comment_arg);
 474     } else
 475       usage();
 476   }
 477
 478   /* Cannot use both -comment and -cfile. */
 479   if (comment_arg != NULL && comment_file != NULL)
 480     usage();
 481   /* If there is neither -comment nor -cfile, we will read the comment text
 482    * from stdin; in this case there MUST be an input JPEG file name.
 483    */
 484   if (comment_arg == NULL && comment_file == NULL && argn >= argc)
 485     usage();
 486
 487   /* Open the input file. */
 488   if (argn < argc) {
 489     if ((infile = fopen(argv[argn], READ_BINARY)) == NULL) {
 490       fprintf(stderr, "%s: can't open %s\n", progname, argv[argn]);
 491       exit(EXIT_FAILURE);
 492     }
 493   } else {
 494     /* default input file is stdin */
 495 #ifdef USE_SETMODE              /* need to hack file mode? */
 496     setmode(fileno(stdin), O_BINARY);
 497 #endif
 498 #ifdef USE_FDOPEN               /* need to re-open in binary mode? */
 499     if ((infile = fdopen(fileno(stdin), READ_BINARY)) == NULL) {
 500       fprintf(stderr, "%s: can't open stdin\n", progname);
 501       exit(EXIT_FAILURE);
 502     }
 503 #else
 504     infile = stdin;
 505 #endif
 506   }
 507
 508   /* Open the output file. */
 509 #ifdef TWO_FILE_COMMANDLINE
 510   /* Must have explicit output file name */
 511   if (argn != argc-2) {
 512     fprintf(stderr, "%s: must name one input and one output file\n",
 513             progname);
 514     usage();
 515   }
 516   if ((outfile = fopen(argv[argn+1], WRITE_BINARY)) == NULL) {
 517     fprintf(stderr, "%s: can't open %s\n", progname, argv[argn+1]);
 518     exit(EXIT_FAILURE);
 519   }
 520 #else
 521   /* Unix style: expect zero or one file name */
 522   if (argn < argc-1) {
 523     fprintf(stderr, "%s: only one input file\n", progname);
 524     usage();
 525   }
 526   /* default output file is stdout */
 527 #ifdef USE_SETMODE              /* need to hack file mode? */
 528   setmode(fileno(stdout), O_BINARY);
 529 #endif
 530 #ifdef USE_FDOPEN               /* need to re-open in binary mode? */
 531   if ((outfile = fdopen(fileno(stdout), WRITE_BINARY)) == NULL) {
 532     fprintf(stderr, "%s: can't open stdout\n", progname);
 533     exit(EXIT_FAILURE);
 534   }
 535 #else
 536   outfile = stdout;
 537 #endif
 538 #endif /* TWO_FILE_COMMANDLINE */
 539
 540   /* Collect comment text from comment_file or stdin, if necessary */
 541   if (comment_arg == NULL) {
 542     FILE * src_file;
 543     int c;
 544
 545     comment_arg = (char *) malloc((size_t) MAX_COM_LENGTH);
 546     if (comment_arg == NULL)
 547       ERREXIT("Insufficient memory");
 548     comment_length = 0;
 549     src_file = (comment_file != NULL ? comment_file : stdin);
 550     while ((c = getc(src_file)) != EOF) {
 551       if (comment_length >= (unsigned int) MAX_COM_LENGTH) {
 552         fprintf(stderr, "Comment text may not exceed %u bytes\n",
 553                 (unsigned int) MAX_COM_LENGTH);
 554         exit(EXIT_FAILURE);
 555       }
 556       comment_arg[comment_length++] = (char) c;
 557     }
 558     if (comment_file != NULL)
 559       fclose(comment_file);
 560   }
 561
 562   /* Copy JPEG headers until SOFn marker;
 563    * we will insert the new comment marker just before SOFn.
 564    * This (a) causes the new comment to appear after, rather than before,
 565    * existing comments; and (b) ensures that comments come after any JFIF
 566    * or JFXX markers, as required by the JFIF specification.
 567    */
 568   marker = scan_JPEG_header(keep_COM);
 569   /* Insert the new COM marker, but only if nonempty text has been supplied */
 570   if (comment_length > 0) {
 571     write_marker(M_COM);
 572     write_2_bytes(comment_length + 2);
 573     while (comment_length > 0) {
 574       write_1_byte(*comment_arg++);
 575       comment_length--;
 576     }
 577   }
 578   /* Duplicate the remainder of the source file.
 579    * Note that any COM markers occuring after SOF will not be touched.
 580    */
 581   write_marker(marker);
 582   copy_rest_of_file();
 583
 584   /* All done. */
 585   exit(EXIT_SUCCESS);
 586   return 0;                     /* suppress no-return-value warnings */
 587 }