/contrib/cvs/diff/diff.c
C | 1266 lines | 937 code | 154 blank | 175 comment | 233 complexity | 287c8ea734c89721622e462ecbe70210 MD5 | raw file
Possible License(s): MPL-2.0-no-copyleft-exception, BSD-3-Clause, LGPL-2.0, LGPL-2.1, BSD-2-Clause, 0BSD, JSON, AGPL-1.0, GPL-2.0
1/* GNU DIFF entry routine. 2 Copyright (C) 1988, 1989, 1992, 1993, 1994, 1997, 1998 Free Software Foundation, Inc. 3 4This file is part of GNU DIFF. 5 6GNU DIFF is free software; you can redistribute it and/or modify 7it under the terms of the GNU General Public License as published by 8the Free Software Foundation; either version 2, or (at your option) 9any later version. 10 11GNU DIFF is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14GNU General Public License for more details. 15 16*/ 17 18/* GNU DIFF was written by Mike Haertel, David Hayes, 19 Richard Stallman, Len Tower, and Paul Eggert. */ 20 21#define GDIFF_MAIN 22#include "diff.h" 23#include <signal.h> 24#include "getopt.h" 25 26#ifdef HAVE_FNMATCH 27# include <fnmatch.h> /* This is supposed to be available on Posix systems */ 28#else /* HAVE_FNMATCH */ 29# include "fnmatch.h" /* Our substitute */ 30#endif /* HAVE_FNMATCH */ 31 32#ifndef DEFAULT_WIDTH 33#define DEFAULT_WIDTH 130 34#endif 35 36#ifndef GUTTER_WIDTH_MINIMUM 37#define GUTTER_WIDTH_MINIMUM 3 38#endif 39 40/* diff.c has a real initialize_main function. */ 41#ifdef initialize_main 42#undef initialize_main 43#endif 44 45static char const *filetype PARAMS((struct stat const *)); 46static char *option_list PARAMS((char **, int)); 47static int add_exclude_file PARAMS((char const *)); 48static int ck_atoi PARAMS((char const *, int *)); 49static int compare_files PARAMS((char const *, char const *, char const *, char const *, int)); 50static int specify_format PARAMS((char **, char *)); 51static void add_exclude PARAMS((char const *)); 52static void add_regexp PARAMS((struct regexp_list **, char const *)); 53static void specify_style PARAMS((enum output_style)); 54static int try_help PARAMS((char const *)); 55static void check_output PARAMS((FILE *)); 56static void usage PARAMS((void)); 57static void initialize_main PARAMS((int *, char ***)); 58 59/* Nonzero for -r: if comparing two directories, 60 compare their common subdirectories recursively. */ 61 62static int recursive; 63 64/* For debugging: don't do discard_confusing_lines. */ 65 66int no_discards; 67 68#if HAVE_SETMODE 69/* I/O mode: nonzero only if using binary input/output. */ 70static int binary_I_O; 71#endif 72 73/* Return a string containing the command options with which diff was invoked. 74 Spaces appear between what were separate ARGV-elements. 75 There is a space at the beginning but none at the end. 76 If there were no options, the result is an empty string. 77 78 Arguments: OPTIONVEC, a vector containing separate ARGV-elements, and COUNT, 79 the length of that vector. */ 80 81static char * 82option_list (optionvec, count) 83 char **optionvec; /* Was `vector', but that collides on Alliant. */ 84 int count; 85{ 86 int i; 87 size_t length = 0; 88 char *result; 89 90 for (i = 0; i < count; i++) 91 length += strlen (optionvec[i]) + 1; 92 93 result = xmalloc (length + 1); 94 result[0] = 0; 95 96 for (i = 0; i < count; i++) 97 { 98 strcat (result, " "); 99 strcat (result, optionvec[i]); 100 } 101 102 return result; 103} 104 105/* Convert STR to a positive integer, storing the result in *OUT. 106 If STR is not a valid integer, return -1 (otherwise 0). */ 107static int 108ck_atoi (str, out) 109 char const *str; 110 int *out; 111{ 112 char const *p; 113 for (p = str; *p; p++) 114 if (*p < '0' || *p > '9') 115 return -1; 116 117 *out = atoi (optarg); 118 return 0; 119} 120 121/* Keep track of excluded file name patterns. */ 122 123static char const **exclude; 124static int exclude_alloc, exclude_count; 125 126int 127excluded_filename (f) 128 char const *f; 129{ 130 int i; 131 for (i = 0; i < exclude_count; i++) 132 if (fnmatch (exclude[i], f, 0) == 0) 133 return 1; 134 return 0; 135} 136 137static void 138add_exclude (pattern) 139 char const *pattern; 140{ 141 if (exclude_alloc <= exclude_count) 142 exclude = (char const **) 143 (exclude_alloc == 0 144 ? xmalloc ((exclude_alloc = 64) * sizeof (*exclude)) 145 : xrealloc (exclude, (exclude_alloc *= 2) * sizeof (*exclude))); 146 147 exclude[exclude_count++] = pattern; 148} 149 150static int 151add_exclude_file (name) 152 char const *name; 153{ 154 struct file_data f; 155 char *p, *q, *lim; 156 157 f.name = optarg; 158 f.desc = (strcmp (optarg, "-") == 0 159 ? STDIN_FILENO 160 : open (optarg, O_RDONLY, 0)); 161 if (f.desc < 0 || fstat (f.desc, &f.stat) != 0) 162 return -1; 163 164 sip (&f, 1); 165 slurp (&f); 166 167 for (p = f.buffer, lim = p + f.buffered_chars; p < lim; p = q) 168 { 169 q = (char *) memchr (p, '\n', lim - p); 170 if (!q) 171 q = lim; 172 *q++ = 0; 173 add_exclude (p); 174 } 175 176 return close (f.desc); 177} 178 179/* The numbers 129- that appear in the fourth element of some entries 180 tell the big switch in `diff_run' how to process those options. */ 181 182static struct option const longopts[] = 183{ 184 {"ignore-blank-lines", 0, 0, 'B'}, 185 {"context", 2, 0, 'C'}, 186 {"ifdef", 1, 0, 'D'}, 187 {"show-function-line", 1, 0, 'F'}, 188 {"speed-large-files", 0, 0, 'H'}, 189 {"ignore-matching-lines", 1, 0, 'I'}, 190 {"label", 1, 0, 'L'}, 191 {"file-label", 1, 0, 'L'}, /* An alias, no longer recommended */ 192 {"new-file", 0, 0, 'N'}, 193 {"entire-new-file", 0, 0, 'N'}, /* An alias, no longer recommended */ 194 {"unidirectional-new-file", 0, 0, 'P'}, 195 {"starting-file", 1, 0, 'S'}, 196 {"initial-tab", 0, 0, 'T'}, 197 {"width", 1, 0, 'W'}, 198 {"text", 0, 0, 'a'}, 199 {"ascii", 0, 0, 'a'}, /* An alias, no longer recommended */ 200 {"ignore-space-change", 0, 0, 'b'}, 201 {"minimal", 0, 0, 'd'}, 202 {"ed", 0, 0, 'e'}, 203 {"forward-ed", 0, 0, 'f'}, 204 {"ignore-case", 0, 0, 'i'}, 205 {"paginate", 0, 0, 'l'}, 206 {"print", 0, 0, 'l'}, /* An alias, no longer recommended */ 207 {"rcs", 0, 0, 'n'}, 208 {"show-c-function", 0, 0, 'p'}, 209 {"brief", 0, 0, 'q'}, 210 {"recursive", 0, 0, 'r'}, 211 {"report-identical-files", 0, 0, 's'}, 212 {"expand-tabs", 0, 0, 't'}, 213 {"version", 0, 0, 'v'}, 214 {"ignore-all-space", 0, 0, 'w'}, 215 {"exclude", 1, 0, 'x'}, 216 {"exclude-from", 1, 0, 'X'}, 217 {"side-by-side", 0, 0, 'y'}, 218 {"unified", 2, 0, 'U'}, 219 {"left-column", 0, 0, 129}, 220 {"suppress-common-lines", 0, 0, 130}, 221 {"sdiff-merge-assist", 0, 0, 131}, 222 {"old-line-format", 1, 0, 132}, 223 {"new-line-format", 1, 0, 133}, 224 {"unchanged-line-format", 1, 0, 134}, 225 {"line-format", 1, 0, 135}, 226 {"old-group-format", 1, 0, 136}, 227 {"new-group-format", 1, 0, 137}, 228 {"unchanged-group-format", 1, 0, 138}, 229 {"changed-group-format", 1, 0, 139}, 230 {"horizon-lines", 1, 0, 140}, 231 {"help", 0, 0, 141}, 232 {"binary", 0, 0, 142}, 233 {0, 0, 0, 0} 234}; 235 236 237 238int 239diff_run (argc, argv, out, callbacks_arg) 240 int argc; 241 char *argv[]; 242 const char *out; 243 const struct diff_callbacks *callbacks_arg; 244{ 245 int val; 246 int c; 247 int prev = -1; 248 int width = DEFAULT_WIDTH; 249 int show_c_function = 0; 250 int optind_old; 251 int opened_file = 0; 252 253 callbacks = callbacks_arg; 254 255 /* Do our initializations. */ 256 initialize_main (&argc, &argv); 257 optind_old = optind; 258 optind = 0; 259 260 /* Set the jump buffer, so that diff may abort execution without 261 terminating the process. */ 262 val = setjmp (diff_abort_buf); 263 if (val != 0) 264 { 265 optind = optind_old; 266 if (opened_file) 267 fclose (outfile); 268 return val; 269 } 270 271 /* Decode the options. */ 272 while ((c = getopt_long (argc, argv, 273 "0123456789abBcC:dD:efF:hHiI:lL:nNpPqrsS:tTuU:vwW:x:X:y", 274 longopts, 0)) != EOF) 275 { 276 switch (c) 277 { 278 /* All digits combine in decimal to specify the context-size. */ 279 case '1': 280 case '2': 281 case '3': 282 case '4': 283 case '5': 284 case '6': 285 case '7': 286 case '8': 287 case '9': 288 case '0': 289 if (context == -1) 290 context = 0; 291 /* If a context length has already been specified, 292 more digits allowed only if they follow right after the others. 293 Reject two separate runs of digits, or digits after -C. */ 294 else if (prev < '0' || prev > '9') 295 fatal ("context length specified twice"); 296 297 context = context * 10 + c - '0'; 298 break; 299 300 case 'a': 301 /* Treat all files as text files; never treat as binary. */ 302 always_text_flag = 1; 303 break; 304 305 case 'b': 306 /* Ignore changes in amount of white space. */ 307 ignore_space_change_flag = 1; 308 ignore_some_changes = 1; 309 ignore_some_line_changes = 1; 310 break; 311 312 case 'B': 313 /* Ignore changes affecting only blank lines. */ 314 ignore_blank_lines_flag = 1; 315 ignore_some_changes = 1; 316 break; 317 318 case 'C': /* +context[=lines] */ 319 case 'U': /* +unified[=lines] */ 320 if (optarg) 321 { 322 if (context >= 0) 323 fatal ("context length specified twice"); 324 325 if (ck_atoi (optarg, &context)) 326 fatal ("invalid context length argument"); 327 } 328 329 /* Falls through. */ 330 case 'c': 331 /* Make context-style output. */ 332 specify_style (c == 'U' ? OUTPUT_UNIFIED : OUTPUT_CONTEXT); 333 break; 334 335 case 'd': 336 /* Don't discard lines. This makes things slower (sometimes much 337 slower) but will find a guaranteed minimal set of changes. */ 338 no_discards = 1; 339 break; 340 341 case 'D': 342 /* Make merged #ifdef output. */ 343 specify_style (OUTPUT_IFDEF); 344 { 345 int i, err = 0; 346 static char const C_ifdef_group_formats[] = 347 "#ifndef %s\n%%<#endif /* not %s */\n%c#ifdef %s\n%%>#endif /* %s */\n%c%%=%c#ifndef %s\n%%<#else /* %s */\n%%>#endif /* %s */\n"; 348 char *b = xmalloc (sizeof (C_ifdef_group_formats) 349 + 7 * strlen(optarg) - 14 /* 7*"%s" */ 350 - 8 /* 5*"%%" + 3*"%c" */); 351 sprintf (b, C_ifdef_group_formats, 352 optarg, optarg, 0, 353 optarg, optarg, 0, 0, 354 optarg, optarg, optarg); 355 for (i = 0; i < 4; i++) 356 { 357 err |= specify_format (&group_format[i], b); 358 b += strlen (b) + 1; 359 } 360 if (err) 361 diff_error ("conflicting #ifdef formats", 0, 0); 362 } 363 break; 364 365 case 'e': 366 /* Make output that is a valid `ed' script. */ 367 specify_style (OUTPUT_ED); 368 break; 369 370 case 'f': 371 /* Make output that looks vaguely like an `ed' script 372 but has changes in the order they appear in the file. */ 373 specify_style (OUTPUT_FORWARD_ED); 374 break; 375 376 case 'F': 377 /* Show, for each set of changes, the previous line that 378 matches the specified regexp. Currently affects only 379 context-style output. */ 380 add_regexp (&function_regexp_list, optarg); 381 break; 382 383 case 'h': 384 /* Split the files into chunks of around 1500 lines 385 for faster processing. Usually does not change the result. 386 387 This currently has no effect. */ 388 break; 389 390 case 'H': 391 /* Turn on heuristics that speed processing of large files 392 with a small density of changes. */ 393 heuristic = 1; 394 break; 395 396 case 'i': 397 /* Ignore changes in case. */ 398 ignore_case_flag = 1; 399 ignore_some_changes = 1; 400 ignore_some_line_changes = 1; 401 break; 402 403 case 'I': 404 /* Ignore changes affecting only lines that match the 405 specified regexp. */ 406 add_regexp (&ignore_regexp_list, optarg); 407 ignore_some_changes = 1; 408 break; 409 410 case 'l': 411 /* Pass the output through `pr' to paginate it. */ 412 paginate_flag = 1; 413#if !defined(SIGCHLD) && defined(SIGCLD) 414#define SIGCHLD SIGCLD 415#endif 416#ifdef SIGCHLD 417 /* Pagination requires forking and waiting, and 418 System V fork+wait does not work if SIGCHLD is ignored. */ 419 signal (SIGCHLD, SIG_DFL); 420#endif 421 break; 422 423 case 'L': 424 /* Specify file labels for `-c' output headers. */ 425 if (!file_label[0]) 426 file_label[0] = optarg; 427 else if (!file_label[1]) 428 file_label[1] = optarg; 429 else 430 fatal ("too many file label options"); 431 break; 432 433 case 'n': 434 /* Output RCS-style diffs, like `-f' except that each command 435 specifies the number of lines affected. */ 436 specify_style (OUTPUT_RCS); 437 break; 438 439 case 'N': 440 /* When comparing directories, if a file appears only in one 441 directory, treat it as present but empty in the other. */ 442 entire_new_file_flag = 1; 443 break; 444 445 case 'p': 446 /* Make context-style output and show name of last C function. */ 447 show_c_function = 1; 448 add_regexp (&function_regexp_list, "^[_a-zA-Z$]"); 449 break; 450 451 case 'P': 452 /* When comparing directories, if a file appears only in 453 the second directory of the two, 454 treat it as present but empty in the other. */ 455 unidirectional_new_file_flag = 1; 456 break; 457 458 case 'q': 459 no_details_flag = 1; 460 break; 461 462 case 'r': 463 /* When comparing directories, 464 recursively compare any subdirectories found. */ 465 recursive = 1; 466 break; 467 468 case 's': 469 /* Print a message if the files are the same. */ 470 print_file_same_flag = 1; 471 break; 472 473 case 'S': 474 /* When comparing directories, start with the specified 475 file name. This is used for resuming an aborted comparison. */ 476 dir_start_file = optarg; 477 break; 478 479 case 't': 480 /* Expand tabs to spaces in the output so that it preserves 481 the alignment of the input files. */ 482 tab_expand_flag = 1; 483 break; 484 485 case 'T': 486 /* Use a tab in the output, rather than a space, before the 487 text of an input line, so as to keep the proper alignment 488 in the input line without changing the characters in it. */ 489 tab_align_flag = 1; 490 break; 491 492 case 'u': 493 /* Output the context diff in unidiff format. */ 494 specify_style (OUTPUT_UNIFIED); 495 break; 496 497 case 'v': 498 if (callbacks && callbacks->write_stdout) 499 { 500 (*callbacks->write_stdout) ("diff - GNU diffutils version "); 501 (*callbacks->write_stdout) (diff_version_string); 502 (*callbacks->write_stdout) ("\n"); 503 } 504 else 505 printf ("diff - GNU diffutils version %s\n", diff_version_string); 506 return 0; 507 508 case 'w': 509 /* Ignore horizontal white space when comparing lines. */ 510 ignore_all_space_flag = 1; 511 ignore_some_changes = 1; 512 ignore_some_line_changes = 1; 513 break; 514 515 case 'x': 516 add_exclude (optarg); 517 break; 518 519 case 'X': 520 if (add_exclude_file (optarg) != 0) 521 pfatal_with_name (optarg); 522 break; 523 524 case 'y': 525 /* Use side-by-side (sdiff-style) columnar output. */ 526 specify_style (OUTPUT_SDIFF); 527 break; 528 529 case 'W': 530 /* Set the line width for OUTPUT_SDIFF. */ 531 if (ck_atoi (optarg, &width) || width <= 0) 532 fatal ("column width must be a positive integer"); 533 break; 534 535 case 129: 536 sdiff_left_only = 1; 537 break; 538 539 case 130: 540 sdiff_skip_common_lines = 1; 541 break; 542 543 case 131: 544 /* sdiff-style columns output. */ 545 specify_style (OUTPUT_SDIFF); 546 sdiff_help_sdiff = 1; 547 break; 548 549 case 132: 550 case 133: 551 case 134: 552 specify_style (OUTPUT_IFDEF); 553 if (specify_format (&line_format[c - 132], optarg) != 0) 554 diff_error ("conflicting line format", 0, 0); 555 break; 556 557 case 135: 558 specify_style (OUTPUT_IFDEF); 559 { 560 int i, err = 0; 561 for (i = 0; i < sizeof (line_format) / sizeof (*line_format); i++) 562 err |= specify_format (&line_format[i], optarg); 563 if (err) 564 diff_error ("conflicting line format", 0, 0); 565 } 566 break; 567 568 case 136: 569 case 137: 570 case 138: 571 case 139: 572 specify_style (OUTPUT_IFDEF); 573 if (specify_format (&group_format[c - 136], optarg) != 0) 574 diff_error ("conflicting group format", 0, 0); 575 break; 576 577 case 140: 578 if (ck_atoi (optarg, &horizon_lines) || horizon_lines < 0) 579 fatal ("horizon must be a nonnegative integer"); 580 break; 581 582 case 141: 583 usage (); 584 if (! callbacks || ! callbacks->write_stdout) 585 check_output (stdout); 586 return 0; 587 588 case 142: 589 /* Use binary I/O when reading and writing data. 590 On Posix hosts, this has no effect. */ 591#if HAVE_SETMODE 592 binary_I_O = 1; 593# if 0 594 /* Because this code is leftover from pre-library days, 595 there is no way to set stdout back to the default mode 596 when we are done. As it turns out, I think the only 597 parts of CVS that pass out == NULL, and thus cause diff 598 to write to stdout, are "cvs diff" and "cvs rdiff". So 599 I'm not going to worry about this too much yet. */ 600 setmode (STDOUT_FILENO, O_BINARY); 601# else 602 if (out == NULL) 603 error (0, 0, "warning: did not set stdout to binary mode"); 604# endif 605#endif 606 break; 607 608 default: 609 return try_help (0); 610 } 611 prev = c; 612 } 613 614 if (argc - optind != 2) 615 return try_help (argc - optind < 2 ? "missing operand" : "extra operand"); 616 617 { 618 /* 619 * We maximize first the half line width, and then the gutter width, 620 * according to the following constraints: 621 * 1. Two half lines plus a gutter must fit in a line. 622 * 2. If the half line width is nonzero: 623 * a. The gutter width is at least GUTTER_WIDTH_MINIMUM. 624 * b. If tabs are not expanded to spaces, 625 * a half line plus a gutter is an integral number of tabs, 626 * so that tabs in the right column line up. 627 */ 628 int t = tab_expand_flag ? 1 : TAB_WIDTH; 629 int off = (width + t + GUTTER_WIDTH_MINIMUM) / (2*t) * t; 630 sdiff_half_width = max (0, min (off - GUTTER_WIDTH_MINIMUM, width - off)), 631 sdiff_column2_offset = sdiff_half_width ? off : width; 632 } 633 634 if (show_c_function && output_style != OUTPUT_UNIFIED) 635 specify_style (OUTPUT_CONTEXT); 636 637 if (output_style != OUTPUT_CONTEXT && output_style != OUTPUT_UNIFIED) 638 context = 0; 639 else if (context == -1) 640 /* Default amount of context for -c. */ 641 context = 3; 642 643 if (output_style == OUTPUT_IFDEF) 644 { 645 /* Format arrays are char *, not char const *, 646 because integer formats are temporarily modified. 647 But it is safe to assign a constant like "%=" to a format array, 648 since "%=" does not format any integers. */ 649 int i; 650 for (i = 0; i < sizeof (line_format) / sizeof (*line_format); i++) 651 if (!line_format[i]) 652 line_format[i] = "%l\n"; 653 if (!group_format[OLD]) 654 group_format[OLD] 655 = group_format[UNCHANGED] ? group_format[UNCHANGED] : "%<"; 656 if (!group_format[NEW]) 657 group_format[NEW] 658 = group_format[UNCHANGED] ? group_format[UNCHANGED] : "%>"; 659 if (!group_format[UNCHANGED]) 660 group_format[UNCHANGED] = "%="; 661 if (!group_format[CHANGED]) 662 group_format[CHANGED] = concat (group_format[OLD], 663 group_format[NEW], ""); 664 } 665 666 no_diff_means_no_output = 667 (output_style == OUTPUT_IFDEF ? 668 (!*group_format[UNCHANGED] 669 || (strcmp (group_format[UNCHANGED], "%=") == 0 670 && !*line_format[UNCHANGED])) 671 : output_style == OUTPUT_SDIFF ? sdiff_skip_common_lines : 1); 672 673 switch_string = option_list (argv + 1, optind - 1); 674 675 if (callbacks && callbacks->write_output) 676 { 677 if (out != NULL) 678 { 679 diff_error ("write callback with output file", 0, 0); 680 return 2; 681 } 682 } 683 else 684 { 685 if (out == NULL) 686 outfile = stdout; 687 else 688 { 689#if HAVE_SETMODE 690 /* A diff which is full of ^Z and such isn't going to work 691 very well in text mode. */ 692 if (binary_I_O) 693 outfile = fopen (out, "wb"); 694 else 695#endif 696 outfile = fopen (out, "w"); 697 if (outfile == NULL) 698 { 699 perror_with_name ("could not open output file"); 700 return 2; 701 } 702 opened_file = 1; 703 } 704 } 705 706 val = compare_files (0, argv[optind], 0, argv[optind + 1], 0); 707 708 /* Print any messages that were saved up for last. */ 709 print_message_queue (); 710 711 free (switch_string); 712 713 optind = optind_old; 714 715 if (! callbacks || ! callbacks->write_output) 716 check_output (outfile); 717 718 if (opened_file) 719 if (fclose (outfile) != 0) 720 perror_with_name ("close error on output file"); 721 722 return val; 723} 724 725/* Add the compiled form of regexp PATTERN to REGLIST. */ 726 727static void 728add_regexp (reglist, pattern) 729 struct regexp_list **reglist; 730 char const *pattern; 731{ 732 struct regexp_list *r; 733 char const *m; 734 735 r = (struct regexp_list *) xmalloc (sizeof (*r)); 736 bzero (r, sizeof (*r)); 737 r->buf.fastmap = xmalloc (256); 738 m = re_compile_pattern (pattern, strlen (pattern), &r->buf); 739 if (m != 0) 740 diff_error ("%s: %s", pattern, m); 741 742 /* Add to the start of the list, since it's easier than the end. */ 743 r->next = *reglist; 744 *reglist = r; 745} 746 747static int 748try_help (reason) 749 char const *reason; 750{ 751 if (reason) 752 diff_error ("%s", reason, 0); 753 diff_error ("Try `%s --help' for more information.", diff_program_name, 0); 754 return 2; 755} 756 757static void 758check_output (file) 759 FILE *file; 760{ 761 if (ferror (file) || fflush (file) != 0) 762 fatal ("write error"); 763} 764 765static char const * const option_help[] = { 766"-i --ignore-case Consider upper- and lower-case to be the same.", 767"-w --ignore-all-space Ignore all white space.", 768"-b --ignore-space-change Ignore changes in the amount of white space.", 769"-B --ignore-blank-lines Ignore changes whose lines are all blank.", 770"-I RE --ignore-matching-lines=RE Ignore changes whose lines all match RE.", 771#if HAVE_SETMODE 772"--binary Read and write data in binary mode.", 773#endif 774"-a --text Treat all files as text.\n", 775"-c -C NUM --context[=NUM] Output NUM (default 2) lines of copied context.", 776"-u -U NUM --unified[=NUM] Output NUM (default 2) lines of unified context.", 777" -NUM Use NUM context lines.", 778" -L LABEL --label LABEL Use LABEL instead of file name.", 779" -p --show-c-function Show which C function each change is in.", 780" -F RE --show-function-line=RE Show the most recent line matching RE.", 781"-q --brief Output only whether files differ.", 782"-e --ed Output an ed script.", 783"-n --rcs Output an RCS format diff.", 784"-y --side-by-side Output in two columns.", 785" -W NUM --width=NUM Output at most NUM (default 130) characters per line.", 786" --left-column Output only the left column of common lines.", 787" --suppress-common-lines Do not output common lines.", 788"-DNAME --ifdef=NAME Output merged file to show `#ifdef NAME' diffs.", 789"--GTYPE-group-format=GFMT Similar, but format GTYPE input groups with GFMT.", 790"--line-format=LFMT Similar, but format all input lines with LFMT.", 791"--LTYPE-line-format=LFMT Similar, but format LTYPE input lines with LFMT.", 792" LTYPE is `old', `new', or `unchanged'. GTYPE is LTYPE or `changed'.", 793" GFMT may contain:", 794" %< lines from FILE1", 795" %> lines from FILE2", 796" %= lines common to FILE1 and FILE2", 797" %[-][WIDTH][.[PREC]]{doxX}LETTER printf-style spec for LETTER", 798" LETTERs are as follows for new group, lower case for old group:", 799" F first line number", 800" L last line number", 801" N number of lines = L-F+1", 802" E F-1", 803" M L+1", 804" LFMT may contain:", 805" %L contents of line", 806" %l contents of line, excluding any trailing newline", 807" %[-][WIDTH][.[PREC]]{doxX}n printf-style spec for input line number", 808" Either GFMT or LFMT may contain:", 809" %% %", 810" %c'C' the single character C", 811" %c'\\OOO' the character with octal code OOO\n", 812"-l --paginate Pass the output through `pr' to paginate it.", 813"-t --expand-tabs Expand tabs to spaces in output.", 814"-T --initial-tab Make tabs line up by prepending a tab.\n", 815"-r --recursive Recursively compare any subdirectories found.", 816"-N --new-file Treat absent files as empty.", 817"-P --unidirectional-new-file Treat absent first files as empty.", 818"-s --report-identical-files Report when two files are the same.", 819"-x PAT --exclude=PAT Exclude files that match PAT.", 820"-X FILE --exclude-from=FILE Exclude files that match any pattern in FILE.", 821"-S FILE --starting-file=FILE Start with FILE when comparing directories.\n", 822"--horizon-lines=NUM Keep NUM lines of the common prefix and suffix.", 823"-d --minimal Try hard to find a smaller set of changes.", 824"-H --speed-large-files Assume large files and many scattered small changes.\n", 825"-v --version Output version info.", 826"--help Output this help.", 8270 828}; 829 830static void 831usage () 832{ 833 char const * const *p; 834 835 if (callbacks && callbacks->write_stdout) 836 { 837 (*callbacks->write_stdout) ("Usage: "); 838 (*callbacks->write_stdout) (diff_program_name); 839 (*callbacks->write_stdout) (" [OPTION]... FILE1 FILE2\n\n"); 840 for (p = option_help; *p; p++) 841 { 842 (*callbacks->write_stdout) (" "); 843 (*callbacks->write_stdout) (*p); 844 (*callbacks->write_stdout) ("\n"); 845 } 846 (*callbacks->write_stdout) 847 ("\nIf FILE1 or FILE2 is `-', read standard input.\n"); 848 } 849 else 850 { 851 printf ("Usage: %s [OPTION]... FILE1 FILE2\n\n", diff_program_name); 852 for (p = option_help; *p; p++) 853 printf (" %s\n", *p); 854 printf ("\nIf FILE1 or FILE2 is `-', read standard input.\n"); 855 } 856} 857 858static int 859specify_format (var, value) 860 char **var; 861 char *value; 862{ 863 int err = *var ? strcmp (*var, value) : 0; 864 *var = value; 865 return err; 866} 867 868static void 869specify_style (style) 870 enum output_style style; 871{ 872 if (output_style != OUTPUT_NORMAL 873 && output_style != style) 874 diff_error ("conflicting specifications of output style", 0, 0); 875 output_style = style; 876} 877 878static char const * 879filetype (st) 880 struct stat const *st; 881{ 882 /* See Posix.2 section 4.17.6.1.1 and Table 5-1 for these formats. 883 To keep diagnostics grammatical, the returned string must start 884 with a consonant. */ 885 886 if (S_ISREG (st->st_mode)) 887 { 888 if (st->st_size == 0) 889 return "regular empty file"; 890 /* Posix.2 section 5.14.2 seems to suggest that we must read the file 891 and guess whether it's C, Fortran, etc., but this is somewhat useless 892 and doesn't reflect historical practice. We're allowed to guess 893 wrong, so we don't bother to read the file. */ 894 return "regular file"; 895 } 896 if (S_ISDIR (st->st_mode)) return "directory"; 897 898 /* other Posix.1 file types */ 899#ifdef S_ISBLK 900 if (S_ISBLK (st->st_mode)) return "block special file"; 901#endif 902#ifdef S_ISCHR 903 if (S_ISCHR (st->st_mode)) return "character special file"; 904#endif 905#ifdef S_ISFIFO 906 if (S_ISFIFO (st->st_mode)) return "fifo"; 907#endif 908 909 /* other Posix.1b file types */ 910#ifdef S_TYPEISMQ 911 if (S_TYPEISMQ (st)) return "message queue"; 912#endif 913#ifdef S_TYPEISSEM 914 if (S_TYPEISSEM (st)) return "semaphore"; 915#endif 916#ifdef S_TYPEISSHM 917 if (S_TYPEISSHM (st)) return "shared memory object"; 918#endif 919 920 /* other popular file types */ 921 /* S_ISLNK is impossible with `fstat' and `stat'. */ 922#ifdef S_ISSOCK 923 if (S_ISSOCK (st->st_mode)) return "socket"; 924#endif 925 926 return "weird file"; 927} 928 929/* Compare two files (or dirs) with specified names 930 DIR0/NAME0 and DIR1/NAME1, at level DEPTH in directory recursion. 931 (if DIR0 is 0, then the name is just NAME0, etc.) 932 This is self-contained; it opens the files and closes them. 933 934 Value is 0 if files are the same, 1 if different, 935 2 if there is a problem opening them. */ 936 937static int 938compare_files (dir0, name0, dir1, name1, depth) 939 char const *dir0, *dir1; 940 char const *name0, *name1; 941 int depth; 942{ 943 struct file_data inf[2]; 944 register int i; 945 int val; 946 int same_files; 947 int failed = 0; 948 char *free0 = 0, *free1 = 0; 949 950 /* If this is directory comparison, perhaps we have a file 951 that exists only in one of the directories. 952 If so, just print a message to that effect. */ 953 954 if (! ((name0 != 0 && name1 != 0) 955 || (unidirectional_new_file_flag && name1 != 0) 956 || entire_new_file_flag)) 957 { 958 char const *name = name0 == 0 ? name1 : name0; 959 char const *dir = name0 == 0 ? dir1 : dir0; 960 message ("Only in %s: %s\n", dir, name); 961 /* Return 1 so that diff_dirs will return 1 ("some files differ"). */ 962 return 1; 963 } 964 965 bzero (inf, sizeof (inf)); 966 967 /* Mark any nonexistent file with -1 in the desc field. */ 968 /* Mark unopened files (e.g. directories) with -2. */ 969 970 inf[0].desc = name0 == 0 ? -1 : -2; 971 inf[1].desc = name1 == 0 ? -1 : -2; 972 973 /* Now record the full name of each file, including nonexistent ones. */ 974 975 if (name0 == 0) 976 name0 = name1; 977 if (name1 == 0) 978 name1 = name0; 979 980 inf[0].name = dir0 == 0 ? name0 : (free0 = dir_file_pathname (dir0, name0)); 981 inf[1].name = dir1 == 0 ? name1 : (free1 = dir_file_pathname (dir1, name1)); 982 983 /* Stat the files. Record whether they are directories. */ 984 985 for (i = 0; i <= 1; i++) 986 { 987 if (inf[i].desc != -1) 988 { 989 int stat_result; 990 991 if (i && filename_cmp (inf[i].name, inf[0].name) == 0) 992 { 993 inf[i].stat = inf[0].stat; 994 stat_result = 0; 995 } 996 else if (strcmp (inf[i].name, "-") == 0) 997 { 998 inf[i].desc = STDIN_FILENO; 999 stat_result = fstat (STDIN_FILENO, &inf[i].stat); 1000 if (stat_result == 0 && S_ISREG (inf[i].stat.st_mode)) 1001 { 1002 off_t pos = lseek (STDIN_FILENO, (off_t) 0, SEEK_CUR); 1003 if (pos == -1) 1004 stat_result = -1; 1005 else 1006 { 1007 if (pos <= inf[i].stat.st_size) 1008 inf[i].stat.st_size -= pos; 1009 else 1010 inf[i].stat.st_size = 0; 1011 /* Posix.2 4.17.6.1.4 requires current time for stdin. */ 1012 time (&inf[i].stat.st_mtime); 1013 } 1014 } 1015 } 1016 else 1017 stat_result = stat (inf[i].name, &inf[i].stat); 1018 1019 if (stat_result != 0) 1020 { 1021 perror_with_name (inf[i].name); 1022 failed = 1; 1023 } 1024 else 1025 { 1026 inf[i].dir_p = S_ISDIR (inf[i].stat.st_mode) && inf[i].desc != 0; 1027 if (inf[1 - i].desc == -1) 1028 { 1029 inf[1 - i].dir_p = inf[i].dir_p; 1030 inf[1 - i].stat.st_mode = inf[i].stat.st_mode; 1031 } 1032 } 1033 } 1034 } 1035 1036 if (! failed && depth == 0 && inf[0].dir_p != inf[1].dir_p) 1037 { 1038 /* If one is a directory, and it was specified in the command line, 1039 use the file in that dir with the other file's basename. */ 1040 1041 int fnm_arg = inf[0].dir_p; 1042 int dir_arg = 1 - fnm_arg; 1043 char const *fnm = inf[fnm_arg].name; 1044 char const *dir = inf[dir_arg].name; 1045 char const *p = filename_lastdirchar (fnm); 1046 char const *filename = inf[dir_arg].name 1047 = dir_file_pathname (dir, p ? p + 1 : fnm); 1048 1049 if (strcmp (fnm, "-") == 0) 1050 fatal ("can't compare - to a directory"); 1051 1052 if (stat (filename, &inf[dir_arg].stat) != 0) 1053 { 1054 perror_with_name (filename); 1055 failed = 1; 1056 } 1057 else 1058 inf[dir_arg].dir_p = S_ISDIR (inf[dir_arg].stat.st_mode); 1059 } 1060 1061 if (failed) 1062 { 1063 1064 /* If either file should exist but does not, return 2. */ 1065 1066 val = 2; 1067 1068 } 1069 else if ((same_files = inf[0].desc != -1 && inf[1].desc != -1 1070 && 0 < same_file (&inf[0].stat, &inf[1].stat)) 1071 && no_diff_means_no_output) 1072 { 1073 /* The two named files are actually the same physical file. 1074 We know they are identical without actually reading them. */ 1075 1076 val = 0; 1077 } 1078 else if (inf[0].dir_p & inf[1].dir_p) 1079 { 1080 if (output_style == OUTPUT_IFDEF) 1081 fatal ("-D option not supported with directories"); 1082 1083 /* If both are directories, compare the files in them. */ 1084 1085 if (depth > 0 && !recursive) 1086 { 1087 /* But don't compare dir contents one level down 1088 unless -r was specified. */ 1089 message ("Common subdirectories: %s and %s\n", 1090 inf[0].name, inf[1].name); 1091 val = 0; 1092 } 1093 else 1094 { 1095 val = diff_dirs (inf, compare_files, depth); 1096 } 1097 1098 } 1099 else if ((inf[0].dir_p | inf[1].dir_p) 1100 || (depth > 0 1101 && (! S_ISREG (inf[0].stat.st_mode) 1102 || ! S_ISREG (inf[1].stat.st_mode)))) 1103 { 1104 /* Perhaps we have a subdirectory that exists only in one directory. 1105 If so, just print a message to that effect. */ 1106 1107 if (inf[0].desc == -1 || inf[1].desc == -1) 1108 { 1109 if ((inf[0].dir_p | inf[1].dir_p) 1110 && recursive 1111 && (entire_new_file_flag 1112 || (unidirectional_new_file_flag && inf[0].desc == -1))) 1113 val = diff_dirs (inf, compare_files, depth); 1114 else 1115 { 1116 char const *dir = (inf[0].desc == -1) ? dir1 : dir0; 1117 /* See Posix.2 section 4.17.6.1.1 for this format. */ 1118 message ("Only in %s: %s\n", dir, name0); 1119 val = 1; 1120 } 1121 } 1122 else 1123 { 1124 /* We have two files that are not to be compared. */ 1125 1126 /* See Posix.2 section 4.17.6.1.1 for this format. */ 1127 message5 ("File %s is a %s while file %s is a %s\n", 1128 inf[0].name, filetype (&inf[0].stat), 1129 inf[1].name, filetype (&inf[1].stat)); 1130 1131 /* This is a difference. */ 1132 val = 1; 1133 } 1134 } 1135 else if ((no_details_flag & ~ignore_some_changes) 1136 && inf[0].stat.st_size != inf[1].stat.st_size 1137 && (inf[0].desc == -1 || S_ISREG (inf[0].stat.st_mode)) 1138 && (inf[1].desc == -1 || S_ISREG (inf[1].stat.st_mode))) 1139 { 1140 message ("Files %s and %s differ\n", inf[0].name, inf[1].name); 1141 val = 1; 1142 } 1143 else 1144 { 1145 /* Both exist and neither is a directory. */ 1146 1147 /* Open the files and record their descriptors. */ 1148 1149 if (inf[0].desc == -2) 1150 if ((inf[0].desc = open (inf[0].name, O_RDONLY, 0)) < 0) 1151 { 1152 perror_with_name (inf[0].name); 1153 failed = 1; 1154 } 1155 if (inf[1].desc == -2) 1156 { 1157 if (same_files) 1158 inf[1].desc = inf[0].desc; 1159 else if ((inf[1].desc = open (inf[1].name, O_RDONLY, 0)) < 0) 1160 { 1161 perror_with_name (inf[1].name); 1162 failed = 1; 1163 } 1164 } 1165 1166#if HAVE_SETMODE 1167 if (binary_I_O) 1168 for (i = 0; i <= 1; i++) 1169 if (0 <= inf[i].desc) 1170 setmode (inf[i].desc, O_BINARY); 1171#endif 1172 1173 /* Compare the files, if no error was found. */ 1174 1175 val = failed ? 2 : diff_2_files (inf, depth); 1176 1177 /* Close the file descriptors. */ 1178 1179 if (inf[0].desc >= 0 && close (inf[0].desc) != 0) 1180 { 1181 perror_with_name (inf[0].name); 1182 val = 2; 1183 } 1184 if (inf[1].desc >= 0 && inf[0].desc != inf[1].desc 1185 && close (inf[1].desc) != 0) 1186 { 1187 perror_with_name (inf[1].name); 1188 val = 2; 1189 } 1190 } 1191 1192 /* Now the comparison has been done, if no error prevented it, 1193 and VAL is the value this function will return. */ 1194 1195 if (val == 0 && !inf[0].dir_p) 1196 { 1197 if (print_file_same_flag) 1198 message ("Files %s and %s are identical\n", 1199 inf[0].name, inf[1].name); 1200 } 1201 else 1202 flush_output (); 1203 1204 if (free0) 1205 free (free0); 1206 if (free1) 1207 free (free1); 1208 1209 return val; 1210} 1211 1212/* Initialize status variables and flag variables used in libdiff, 1213 to permit repeated calls to diff_run. */ 1214 1215static void 1216initialize_main (argcp, argvp) 1217 int *argcp; 1218 char ***argvp; 1219{ 1220 /* These variables really must be reset each time diff_run is called. */ 1221 output_style = OUTPUT_NORMAL; 1222 context = -1; 1223 file_label[0] = NULL; 1224 file_label[1] = NULL; 1225 diff_program_name = (*argvp)[0]; 1226 outfile = NULL; 1227 1228 /* Reset these also, just for safety's sake. (If one invocation turns 1229 on ignore_case_flag, it must be turned off before diff_run is called 1230 again. But it is possible to make many diffs before encountering 1231 such a problem. */ 1232 recursive = 0; 1233 no_discards = 0; 1234#if HAVE_SETMODE 1235 binary_I_O = 0; 1236#endif 1237 no_diff_means_no_output = 0; 1238 always_text_flag = 0; 1239 horizon_lines = 0; 1240 ignore_space_change_flag = 0; 1241 ignore_all_space_flag = 0; 1242 ignore_blank_lines_flag = 0; 1243 ignore_some_line_changes = 0; 1244 ignore_some_changes = 0; 1245 ignore_case_flag = 0; 1246 function_regexp_list = NULL; 1247 ignore_regexp_list = NULL; 1248 no_details_flag = 0; 1249 print_file_same_flag = 0; 1250 tab_align_flag = 0; 1251 tab_expand_flag = 0; 1252 dir_start_file = NULL; 1253 entire_new_file_flag = 0; 1254 unidirectional_new_file_flag = 0; 1255 paginate_flag = 0; 1256 bzero (group_format, sizeof (group_format)); 1257 bzero (line_format, sizeof (line_format)); 1258 sdiff_help_sdiff = 0; 1259 sdiff_left_only = 0; 1260 sdiff_skip_common_lines = 0; 1261 sdiff_half_width = 0; 1262 sdiff_column2_offset = 0; 1263 switch_string = NULL; 1264 heuristic = 0; 1265 bzero (files, sizeof (files)); 1266}