1 /* $OpenBSD: diffreg.c,v 1.93 2019/06/28 13:35:00 deraadt Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-4-Clause 5 * 6 * Copyright (C) Caldera International Inc. 2001-2002. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code and documentation must retain the above 13 * copyright notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed or owned by Caldera 20 * International, Inc. 21 * 4. Neither the name of Caldera International, Inc. nor the names of other 22 * contributors may be used to endorse or promote products derived from 23 * this software without specific prior written permission. 24 * 25 * USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA 26 * INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT, 30 * INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 31 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 34 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 35 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 /*- 39 * Copyright (c) 1991, 1993 40 * The Regents of the University of California. All rights reserved. 41 * 42 * Redistribution and use in source and binary forms, with or without 43 * modification, are permitted provided that the following conditions 44 * are met: 45 * 1. Redistributions of source code must retain the above copyright 46 * notice, this list of conditions and the following disclaimer. 47 * 2. Redistributions in binary form must reproduce the above copyright 48 * notice, this list of conditions and the following disclaimer in the 49 * documentation and/or other materials provided with the distribution. 50 * 3. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * @(#)diffreg.c 8.1 (Berkeley) 6/6/93 67 */ 68 69 #include <sys/cdefs.h> 70 __FBSDID("$FreeBSD$"); 71 72 #include <sys/capsicum.h> 73 #include <sys/stat.h> 74 75 #include <capsicum_helpers.h> 76 #include <ctype.h> 77 #include <err.h> 78 #include <errno.h> 79 #include <fcntl.h> 80 #include <paths.h> 81 #include <regex.h> 82 #include <stdbool.h> 83 #include <stddef.h> 84 #include <stdint.h> 85 #include <stdio.h> 86 #include <stdlib.h> 87 #include <string.h> 88 89 #include "pr.h" 90 #include "diff.h" 91 #include "xmalloc.h" 92 93 /* 94 * diff - compare two files. 95 */ 96 97 /* 98 * Uses an algorithm due to Harold Stone, which finds 99 * a pair of longest identical subsequences in the two 100 * files. 101 * 102 * The major goal is to generate the match vector J. 103 * J[i] is the index of the line in file1 corresponding 104 * to line i file0. J[i] = 0 if there is no 105 * such line in file1. 106 * 107 * Lines are hashed so as to work in core. All potential 108 * matches are located by sorting the lines of each file 109 * on the hash (called ``value''). In particular, this 110 * collects the equivalence classes in file1 together. 111 * Subroutine equiv replaces the value of each line in 112 * file0 by the index of the first element of its 113 * matching equivalence in (the reordered) file1. 114 * To save space equiv squeezes file1 into a single 115 * array member in which the equivalence classes 116 * are simply concatenated, except that their first 117 * members are flagged by changing sign. 118 * 119 * Next the indices that point into member are unsorted into 120 * array class according to the original order of file0. 121 * 122 * The cleverness lies in routine stone. This marches 123 * through the lines of file0, developing a vector klist 124 * of "k-candidates". At step i a k-candidate is a matched 125 * pair of lines x,y (x in file0 y in file1) such that 126 * there is a common subsequence of length k 127 * between the first i lines of file0 and the first y 128 * lines of file1, but there is no such subsequence for 129 * any smaller y. x is the earliest possible mate to y 130 * that occurs in such a subsequence. 131 * 132 * Whenever any of the members of the equivalence class of 133 * lines in file1 matable to a line in file0 has serial number 134 * less than the y of some k-candidate, that k-candidate 135 * with the smallest such y is replaced. The new 136 * k-candidate is chained (via pred) to the current 137 * k-1 candidate so that the actual subsequence can 138 * be recovered. When a member has serial number greater 139 * that the y of all k-candidates, the klist is extended. 140 * At the end, the longest subsequence is pulled out 141 * and placed in the array J by unravel 142 * 143 * With J in hand, the matches there recorded are 144 * check'ed against reality to assure that no spurious 145 * matches have crept in due to hashing. If they have, 146 * they are broken, and "jackpot" is recorded--a harmless 147 * matter except that a true match for a spuriously 148 * mated line may now be unnecessarily reported as a change. 149 * 150 * Much of the complexity of the program comes simply 151 * from trying to minimize core utilization and 152 * maximize the range of doable problems by dynamically 153 * allocating what is needed and reusing what is not. 154 * The core requirements for problems larger than somewhat 155 * are (in words) 2*length(file0) + length(file1) + 156 * 3*(number of k-candidates installed), typically about 157 * 6n words for files of length n. 158 */ 159 160 struct cand { 161 int x; 162 int y; 163 int pred; 164 }; 165 166 static struct line { 167 int serial; 168 int value; 169 } *file[2]; 170 171 /* 172 * The following struct is used to record change information when 173 * doing a "context" or "unified" diff. (see routine "change" to 174 * understand the highly mnemonic field names) 175 */ 176 struct context_vec { 177 int a; /* start line in old file */ 178 int b; /* end line in old file */ 179 int c; /* start line in new file */ 180 int d; /* end line in new file */ 181 }; 182 183 enum readhash { RH_BINARY, RH_OK, RH_EOF }; 184 185 #define MIN_PAD 1 186 static FILE *opentemp(const char *); 187 static void output(char *, FILE *, char *, FILE *, int); 188 static void check(FILE *, FILE *, int); 189 static void range(int, int, const char *); 190 static void uni_range(int, int); 191 static void dump_context_vec(FILE *, FILE *, int); 192 static void dump_unified_vec(FILE *, FILE *, int); 193 static bool prepare(int, FILE *, size_t, int); 194 static void prune(void); 195 static void equiv(struct line *, int, struct line *, int, int *); 196 static void unravel(int); 197 static void unsort(struct line *, int, int *); 198 static void change(char *, FILE *, char *, FILE *, int, int, int, int, int *); 199 static void sort(struct line *, int); 200 static void print_header(const char *, const char *); 201 static void print_space(int, int, int); 202 static bool ignoreline_pattern(char *); 203 static bool ignoreline(char *, bool); 204 static int asciifile(FILE *); 205 static int fetch(long *, int, int, FILE *, int, int, int); 206 static int newcand(int, int, int); 207 static int search(int *, int, int); 208 static int skipline(FILE *); 209 static int isqrt(int); 210 static int stone(int *, int, int *, int *, int); 211 static enum readhash readhash(FILE *, int, unsigned *); 212 static int files_differ(FILE *, FILE *, int); 213 static char *match_function(const long *, int, FILE *); 214 static char *preadline(int, size_t, off_t); 215 216 static int *J; /* will be overlaid on class */ 217 static int *class; /* will be overlaid on file[0] */ 218 static int *klist; /* will be overlaid on file[0] after class */ 219 static int *member; /* will be overlaid on file[1] */ 220 static int clen; 221 static int inifdef; /* whether or not we are in a #ifdef block */ 222 static int len[2]; 223 static int pref, suff; /* length of prefix and suffix */ 224 static int slen[2]; 225 static int anychange; 226 static int hw, padding; /* half width and padding */ 227 static int edoffset; 228 static long *ixnew; /* will be overlaid on file[1] */ 229 static long *ixold; /* will be overlaid on klist */ 230 static struct cand *clist; /* merely a free storage pot for candidates */ 231 static int clistlen; /* the length of clist */ 232 static struct line *sfile[2]; /* shortened by pruning common prefix/suffix */ 233 static int (*chrtran)(int); /* translation table for case-folding */ 234 static struct context_vec *context_vec_start; 235 static struct context_vec *context_vec_end; 236 static struct context_vec *context_vec_ptr; 237 238 #define FUNCTION_CONTEXT_SIZE 55 239 static char lastbuf[FUNCTION_CONTEXT_SIZE]; 240 static int lastline; 241 static int lastmatchline; 242 243 static int 244 clow2low(int c) 245 { 246 247 return (c); 248 } 249 250 static int 251 cup2low(int c) 252 { 253 254 return tolower(c); 255 } 256 257 int 258 diffreg(char *file1, char *file2, int flags, int capsicum) 259 { 260 FILE *f1, *f2; 261 int i, rval; 262 struct pr *pr = NULL; 263 cap_rights_t rights_ro; 264 265 f1 = f2 = NULL; 266 rval = D_SAME; 267 anychange = 0; 268 lastline = 0; 269 lastmatchline = 0; 270 context_vec_ptr = context_vec_start - 1; 271 272 /* 273 * hw excludes padding and make sure when -t is not used, 274 * the second column always starts from the closest tab stop 275 */ 276 if (diff_format == D_SIDEBYSIDE) { 277 hw = width >> 1; 278 padding = tabsize - (hw % tabsize); 279 if ((flags & D_EXPANDTABS) != 0 || (padding % tabsize == 0)) 280 padding = MIN_PAD; 281 282 hw = (width >> 1) - 283 ((padding == MIN_PAD) ? (padding << 1) : padding) - 1; 284 } 285 286 287 if (flags & D_IGNORECASE) 288 chrtran = cup2low; 289 else 290 chrtran = clow2low; 291 if (S_ISDIR(stb1.st_mode) != S_ISDIR(stb2.st_mode)) 292 return (S_ISDIR(stb1.st_mode) ? D_MISMATCH1 : D_MISMATCH2); 293 if (strcmp(file1, "-") == 0 && strcmp(file2, "-") == 0) 294 goto closem; 295 296 if (flags & D_EMPTY1) 297 f1 = fopen(_PATH_DEVNULL, "r"); 298 else { 299 if (!S_ISREG(stb1.st_mode)) { 300 if ((f1 = opentemp(file1)) == NULL || 301 fstat(fileno(f1), &stb1) == -1) { 302 warn("%s", file1); 303 rval = D_ERROR; 304 status |= 2; 305 goto closem; 306 } 307 } else if (strcmp(file1, "-") == 0) 308 f1 = stdin; 309 else 310 f1 = fopen(file1, "r"); 311 } 312 if (f1 == NULL) { 313 warn("%s", file1); 314 rval = D_ERROR; 315 status |= 2; 316 goto closem; 317 } 318 319 if (flags & D_EMPTY2) 320 f2 = fopen(_PATH_DEVNULL, "r"); 321 else { 322 if (!S_ISREG(stb2.st_mode)) { 323 if ((f2 = opentemp(file2)) == NULL || 324 fstat(fileno(f2), &stb2) == -1) { 325 warn("%s", file2); 326 rval = D_ERROR; 327 status |= 2; 328 goto closem; 329 } 330 } else if (strcmp(file2, "-") == 0) 331 f2 = stdin; 332 else 333 f2 = fopen(file2, "r"); 334 } 335 if (f2 == NULL) { 336 warn("%s", file2); 337 rval = D_ERROR; 338 status |= 2; 339 goto closem; 340 } 341 342 if (lflag) 343 pr = start_pr(file1, file2); 344 345 if (capsicum) { 346 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); 347 if (caph_rights_limit(fileno(f1), &rights_ro) < 0) 348 err(2, "unable to limit rights on: %s", file1); 349 if (caph_rights_limit(fileno(f2), &rights_ro) < 0) 350 err(2, "unable to limit rights on: %s", file2); 351 if (fileno(f1) == STDIN_FILENO || fileno(f2) == STDIN_FILENO) { 352 /* stdin has already been limited */ 353 if (caph_limit_stderr() == -1) 354 err(2, "unable to limit stderr"); 355 if (caph_limit_stdout() == -1) 356 err(2, "unable to limit stdout"); 357 } else if (caph_limit_stdio() == -1) 358 err(2, "unable to limit stdio"); 359 360 caph_cache_catpages(); 361 caph_cache_tzdata(); 362 if (caph_enter() < 0) 363 err(2, "unable to enter capability mode"); 364 } 365 366 switch (files_differ(f1, f2, flags)) { 367 case 0: 368 goto closem; 369 case 1: 370 break; 371 default: 372 /* error */ 373 rval = D_ERROR; 374 status |= 2; 375 goto closem; 376 } 377 378 if (diff_format == D_BRIEF && ignore_pats == NULL && 379 (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE|D_STRIPCR)) == 0) 380 { 381 rval = D_DIFFER; 382 status |= 1; 383 goto closem; 384 } 385 if ((flags & D_FORCEASCII) != 0) { 386 (void)prepare(0, f1, stb1.st_size, flags); 387 (void)prepare(1, f2, stb2.st_size, flags); 388 } else if (!asciifile(f1) || !asciifile(f2) || 389 !prepare(0, f1, stb1.st_size, flags) || 390 !prepare(1, f2, stb2.st_size, flags)) { 391 rval = D_BINARY; 392 status |= 1; 393 goto closem; 394 } 395 396 prune(); 397 sort(sfile[0], slen[0]); 398 sort(sfile[1], slen[1]); 399 400 member = (int *)file[1]; 401 equiv(sfile[0], slen[0], sfile[1], slen[1], member); 402 member = xreallocarray(member, slen[1] + 2, sizeof(*member)); 403 404 class = (int *)file[0]; 405 unsort(sfile[0], slen[0], class); 406 class = xreallocarray(class, slen[0] + 2, sizeof(*class)); 407 408 klist = xcalloc(slen[0] + 2, sizeof(*klist)); 409 clen = 0; 410 clistlen = 100; 411 clist = xcalloc(clistlen, sizeof(*clist)); 412 i = stone(class, slen[0], member, klist, flags); 413 free(member); 414 free(class); 415 416 J = xreallocarray(J, len[0] + 2, sizeof(*J)); 417 unravel(klist[i]); 418 free(clist); 419 free(klist); 420 421 ixold = xreallocarray(ixold, len[0] + 2, sizeof(*ixold)); 422 ixnew = xreallocarray(ixnew, len[1] + 2, sizeof(*ixnew)); 423 check(f1, f2, flags); 424 output(file1, f1, file2, f2, flags); 425 426 closem: 427 if (pr != NULL) 428 stop_pr(pr); 429 if (anychange) { 430 status |= 1; 431 if (rval == D_SAME) 432 rval = D_DIFFER; 433 } 434 if (f1 != NULL) 435 fclose(f1); 436 if (f2 != NULL) 437 fclose(f2); 438 439 return (rval); 440 } 441 442 /* 443 * Check to see if the given files differ. 444 * Returns 0 if they are the same, 1 if different, and -1 on error. 445 * XXX - could use code from cmp(1) [faster] 446 */ 447 static int 448 files_differ(FILE *f1, FILE *f2, int flags) 449 { 450 char buf1[BUFSIZ], buf2[BUFSIZ]; 451 size_t i, j; 452 453 if ((flags & (D_EMPTY1|D_EMPTY2)) || stb1.st_size != stb2.st_size || 454 (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)) 455 return (1); 456 for (;;) { 457 i = fread(buf1, 1, sizeof(buf1), f1); 458 j = fread(buf2, 1, sizeof(buf2), f2); 459 if ((!i && ferror(f1)) || (!j && ferror(f2))) 460 return (-1); 461 if (i != j) 462 return (1); 463 if (i == 0) 464 return (0); 465 if (memcmp(buf1, buf2, i) != 0) 466 return (1); 467 } 468 } 469 470 static FILE * 471 opentemp(const char *f) 472 { 473 char buf[BUFSIZ], tempfile[PATH_MAX]; 474 ssize_t nread; 475 int ifd, ofd; 476 477 if (strcmp(f, "-") == 0) 478 ifd = STDIN_FILENO; 479 else if ((ifd = open(f, O_RDONLY, 0644)) == -1) 480 return (NULL); 481 482 (void)strlcpy(tempfile, _PATH_TMP "/diff.XXXXXXXX", sizeof(tempfile)); 483 484 if ((ofd = mkstemp(tempfile)) == -1) { 485 close(ifd); 486 return (NULL); 487 } 488 unlink(tempfile); 489 while ((nread = read(ifd, buf, BUFSIZ)) > 0) { 490 if (write(ofd, buf, nread) != nread) { 491 close(ifd); 492 close(ofd); 493 return (NULL); 494 } 495 } 496 close(ifd); 497 lseek(ofd, (off_t)0, SEEK_SET); 498 return (fdopen(ofd, "r")); 499 } 500 501 char * 502 splice(char *dir, char *path) 503 { 504 char *tail, *buf; 505 size_t dirlen; 506 507 dirlen = strlen(dir); 508 while (dirlen != 0 && dir[dirlen - 1] == '/') 509 dirlen--; 510 if ((tail = strrchr(path, '/')) == NULL) 511 tail = path; 512 else 513 tail++; 514 xasprintf(&buf, "%.*s/%s", (int)dirlen, dir, tail); 515 return (buf); 516 } 517 518 static bool 519 prepare(int i, FILE *fd, size_t filesize, int flags) 520 { 521 struct line *p; 522 unsigned h; 523 size_t sz, j = 0; 524 enum readhash r; 525 526 rewind(fd); 527 528 sz = MIN(filesize, SIZE_MAX) / 25; 529 if (sz < 100) 530 sz = 100; 531 532 p = xcalloc(sz + 3, sizeof(*p)); 533 while ((r = readhash(fd, flags, &h)) != RH_EOF) 534 switch (r) { 535 case RH_EOF: /* otherwise clang complains */ 536 case RH_BINARY: 537 return (false); 538 case RH_OK: 539 if (j == sz) { 540 sz = sz * 3 / 2; 541 p = xreallocarray(p, sz + 3, sizeof(*p)); 542 } 543 p[++j].value = h; 544 } 545 546 len[i] = j; 547 file[i] = p; 548 549 return (true); 550 } 551 552 static void 553 prune(void) 554 { 555 int i, j; 556 557 for (pref = 0; pref < len[0] && pref < len[1] && 558 file[0][pref + 1].value == file[1][pref + 1].value; 559 pref++) 560 ; 561 for (suff = 0; suff < len[0] - pref && suff < len[1] - pref && 562 file[0][len[0] - suff].value == file[1][len[1] - suff].value; 563 suff++) 564 ; 565 for (j = 0; j < 2; j++) { 566 sfile[j] = file[j] + pref; 567 slen[j] = len[j] - pref - suff; 568 for (i = 0; i <= slen[j]; i++) 569 sfile[j][i].serial = i; 570 } 571 } 572 573 static void 574 equiv(struct line *a, int n, struct line *b, int m, int *c) 575 { 576 int i, j; 577 578 i = j = 1; 579 while (i <= n && j <= m) { 580 if (a[i].value < b[j].value) 581 a[i++].value = 0; 582 else if (a[i].value == b[j].value) 583 a[i++].value = j; 584 else 585 j++; 586 } 587 while (i <= n) 588 a[i++].value = 0; 589 b[m + 1].value = 0; 590 j = 0; 591 while (++j <= m) { 592 c[j] = -b[j].serial; 593 while (b[j + 1].value == b[j].value) { 594 j++; 595 c[j] = b[j].serial; 596 } 597 } 598 c[j] = -1; 599 } 600 601 /* Code taken from ping.c */ 602 static int 603 isqrt(int n) 604 { 605 int y, x = 1; 606 607 if (n == 0) 608 return (0); 609 610 do { /* newton was a stinker */ 611 y = x; 612 x = n / x; 613 x += y; 614 x /= 2; 615 } while ((x - y) > 1 || (x - y) < -1); 616 617 return (x); 618 } 619 620 static int 621 stone(int *a, int n, int *b, int *c, int flags) 622 { 623 int i, k, y, j, l; 624 int oldc, tc, oldl, sq; 625 u_int numtries, bound; 626 627 if (flags & D_MINIMAL) 628 bound = UINT_MAX; 629 else { 630 sq = isqrt(n); 631 bound = MAX(256, sq); 632 } 633 634 k = 0; 635 c[0] = newcand(0, 0, 0); 636 for (i = 1; i <= n; i++) { 637 j = a[i]; 638 if (j == 0) 639 continue; 640 y = -b[j]; 641 oldl = 0; 642 oldc = c[0]; 643 numtries = 0; 644 do { 645 if (y <= clist[oldc].y) 646 continue; 647 l = search(c, k, y); 648 if (l != oldl + 1) 649 oldc = c[l - 1]; 650 if (l <= k) { 651 if (clist[c[l]].y <= y) 652 continue; 653 tc = c[l]; 654 c[l] = newcand(i, y, oldc); 655 oldc = tc; 656 oldl = l; 657 numtries++; 658 } else { 659 c[l] = newcand(i, y, oldc); 660 k++; 661 break; 662 } 663 } while ((y = b[++j]) > 0 && numtries < bound); 664 } 665 return (k); 666 } 667 668 static int 669 newcand(int x, int y, int pred) 670 { 671 struct cand *q; 672 673 if (clen == clistlen) { 674 clistlen = clistlen * 11 / 10; 675 clist = xreallocarray(clist, clistlen, sizeof(*clist)); 676 } 677 q = clist + clen; 678 q->x = x; 679 q->y = y; 680 q->pred = pred; 681 return (clen++); 682 } 683 684 static int 685 search(int *c, int k, int y) 686 { 687 int i, j, l, t; 688 689 if (clist[c[k]].y < y) /* quick look for typical case */ 690 return (k + 1); 691 i = 0; 692 j = k + 1; 693 for (;;) { 694 l = (i + j) / 2; 695 if (l <= i) 696 break; 697 t = clist[c[l]].y; 698 if (t > y) 699 j = l; 700 else if (t < y) 701 i = l; 702 else 703 return (l); 704 } 705 return (l + 1); 706 } 707 708 static void 709 unravel(int p) 710 { 711 struct cand *q; 712 int i; 713 714 for (i = 0; i <= len[0]; i++) 715 J[i] = i <= pref ? i : 716 i > len[0] - suff ? i + len[1] - len[0] : 0; 717 for (q = clist + p; q->y != 0; q = clist + q->pred) 718 J[q->x + pref] = q->y + pref; 719 } 720 721 /* 722 * Check does double duty: 723 * 1. ferret out any fortuitous correspondences due 724 * to confounding by hashing (which result in "jackpot") 725 * 2. collect random access indexes to the two files 726 */ 727 static void 728 check(FILE *f1, FILE *f2, int flags) 729 { 730 int i, j, jackpot, c, d; 731 long ctold, ctnew; 732 733 rewind(f1); 734 rewind(f2); 735 j = 1; 736 ixold[0] = ixnew[0] = 0; 737 jackpot = 0; 738 ctold = ctnew = 0; 739 for (i = 1; i <= len[0]; i++) { 740 if (J[i] == 0) { 741 ixold[i] = ctold += skipline(f1); 742 continue; 743 } 744 while (j < J[i]) { 745 ixnew[j] = ctnew += skipline(f2); 746 j++; 747 } 748 if (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE|D_STRIPCR)) { 749 for (;;) { 750 c = getc(f1); 751 d = getc(f2); 752 /* 753 * GNU diff ignores a missing newline 754 * in one file for -b or -w. 755 */ 756 if (flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) { 757 if (c == EOF && d == '\n') { 758 ctnew++; 759 break; 760 } else if (c == '\n' && d == EOF) { 761 ctold++; 762 break; 763 } 764 } 765 ctold++; 766 ctnew++; 767 if (flags & D_STRIPCR && (c == '\r' || d == '\r')) { 768 if (c == '\r') { 769 if ((c = getc(f1)) == '\n') { 770 ctold++; 771 } else { 772 ungetc(c, f1); 773 } 774 } 775 if (d == '\r') { 776 if ((d = getc(f2)) == '\n') { 777 ctnew++; 778 } else { 779 ungetc(d, f2); 780 } 781 } 782 break; 783 } 784 if ((flags & D_FOLDBLANKS) && isspace(c) && 785 isspace(d)) { 786 do { 787 if (c == '\n') 788 break; 789 ctold++; 790 } while (isspace(c = getc(f1))); 791 do { 792 if (d == '\n') 793 break; 794 ctnew++; 795 } while (isspace(d = getc(f2))); 796 } else if ((flags & D_IGNOREBLANKS)) { 797 while (isspace(c) && c != '\n') { 798 c = getc(f1); 799 ctold++; 800 } 801 while (isspace(d) && d != '\n') { 802 d = getc(f2); 803 ctnew++; 804 } 805 } 806 if (chrtran(c) != chrtran(d)) { 807 jackpot++; 808 J[i] = 0; 809 if (c != '\n' && c != EOF) 810 ctold += skipline(f1); 811 if (d != '\n' && c != EOF) 812 ctnew += skipline(f2); 813 break; 814 } 815 if (c == '\n' || c == EOF) 816 break; 817 } 818 } else { 819 for (;;) { 820 ctold++; 821 ctnew++; 822 if ((c = getc(f1)) != (d = getc(f2))) { 823 /* jackpot++; */ 824 J[i] = 0; 825 if (c != '\n' && c != EOF) 826 ctold += skipline(f1); 827 if (d != '\n' && c != EOF) 828 ctnew += skipline(f2); 829 break; 830 } 831 if (c == '\n' || c == EOF) 832 break; 833 } 834 } 835 ixold[i] = ctold; 836 ixnew[j] = ctnew; 837 j++; 838 } 839 for (; j <= len[1]; j++) { 840 ixnew[j] = ctnew += skipline(f2); 841 } 842 /* 843 * if (jackpot) 844 * fprintf(stderr, "jackpot\n"); 845 */ 846 } 847 848 /* shellsort CACM #201 */ 849 static void 850 sort(struct line *a, int n) 851 { 852 struct line *ai, *aim, w; 853 int j, m = 0, k; 854 855 if (n == 0) 856 return; 857 for (j = 1; j <= n; j *= 2) 858 m = 2 * j - 1; 859 for (m /= 2; m != 0; m /= 2) { 860 k = n - m; 861 for (j = 1; j <= k; j++) { 862 for (ai = &a[j]; ai > a; ai -= m) { 863 aim = &ai[m]; 864 if (aim < ai) 865 break; /* wraparound */ 866 if (aim->value > ai[0].value || 867 (aim->value == ai[0].value && 868 aim->serial > ai[0].serial)) 869 break; 870 w.value = ai[0].value; 871 ai[0].value = aim->value; 872 aim->value = w.value; 873 w.serial = ai[0].serial; 874 ai[0].serial = aim->serial; 875 aim->serial = w.serial; 876 } 877 } 878 } 879 } 880 881 static void 882 unsort(struct line *f, int l, int *b) 883 { 884 int *a, i; 885 886 a = xcalloc(l + 1, sizeof(*a)); 887 for (i = 1; i <= l; i++) 888 a[f[i].serial] = f[i].value; 889 for (i = 1; i <= l; i++) 890 b[i] = a[i]; 891 free(a); 892 } 893 894 static int 895 skipline(FILE *f) 896 { 897 int i, c; 898 899 for (i = 1; (c = getc(f)) != '\n' && c != EOF; i++) 900 continue; 901 return (i); 902 } 903 904 static void 905 output(char *file1, FILE *f1, char *file2, FILE *f2, int flags) 906 { 907 int i, j, m, i0, i1, j0, j1, nc; 908 909 rewind(f1); 910 rewind(f2); 911 m = len[0]; 912 J[0] = 0; 913 J[m + 1] = len[1] + 1; 914 if (diff_format != D_EDIT) { 915 for (i0 = 1; i0 <= m; i0 = i1 + 1) { 916 while (i0 <= m && J[i0] == J[i0 - 1] + 1){ 917 if (diff_format == D_SIDEBYSIDE && 918 suppress_common != 1) { 919 nc = fetch(ixold, i0, i0, f1, '\0', 920 1, flags); 921 print_space(nc, 922 (hw - nc) + (padding << 1) + 1, 923 flags); 924 fetch(ixnew, J[i0], J[i0], f2, '\0', 925 0, flags); 926 printf("\n"); 927 } 928 i0++; 929 } 930 j0 = J[i0 - 1] + 1; 931 i1 = i0 - 1; 932 while (i1 < m && J[i1 + 1] == 0) 933 i1++; 934 j1 = J[i1 + 1] - 1; 935 J[i1] = j1; 936 937 /* 938 * When using side-by-side, lines from both of the 939 * files are printed. The algorithm used by diff(1) 940 * identifies the ranges in which two files differ. 941 * See the change() function below. 942 * The for loop below consumes the shorter range, 943 * whereas one of the while loops deals with the 944 * longer one. 945 */ 946 if (diff_format == D_SIDEBYSIDE) { 947 for (i=i0, j=j0; i<=i1 && j<=j1; i++, j++) 948 change(file1, f1, file2, f2, i, i, 949 j, j, &flags); 950 951 while (i <= i1) { 952 change(file1, f1, file2, f2, 953 i, i, j+1, j, &flags); 954 i++; 955 } 956 957 while (j <= j1) { 958 change(file1, f1, file2, f2, 959 i+1, i, j, j, &flags); 960 j++; 961 } 962 } else 963 change(file1, f1, file2, f2, i0, i1, j0, 964 j1, &flags); 965 } 966 } else { 967 for (i0 = m; i0 >= 1; i0 = i1 - 1) { 968 while (i0 >= 1 && J[i0] == J[i0 + 1] - 1 && J[i0] != 0) 969 i0--; 970 j0 = J[i0 + 1] - 1; 971 i1 = i0 + 1; 972 while (i1 > 1 && J[i1 - 1] == 0) 973 i1--; 974 j1 = J[i1 - 1] + 1; 975 J[i1] = j1; 976 change(file1, f1, file2, f2, i1, i0, j1, j0, &flags); 977 } 978 } 979 if (m == 0) 980 change(file1, f1, file2, f2, 1, 0, 1, len[1], &flags); 981 if (diff_format == D_IFDEF || diff_format == D_GFORMAT) { 982 for (;;) { 983 #define c i0 984 if ((c = getc(f1)) == EOF) 985 return; 986 printf("%c", c); 987 } 988 #undef c 989 } 990 if (anychange != 0) { 991 if (diff_format == D_CONTEXT) 992 dump_context_vec(f1, f2, flags); 993 else if (diff_format == D_UNIFIED) 994 dump_unified_vec(f1, f2, flags); 995 } 996 } 997 998 static void 999 range(int a, int b, const char *separator) 1000 { 1001 printf("%d", a > b ? b : a); 1002 if (a < b) 1003 printf("%s%d", separator, b); 1004 } 1005 1006 static void 1007 uni_range(int a, int b) 1008 { 1009 if (a < b) 1010 printf("%d,%d", a, b - a + 1); 1011 else if (a == b) 1012 printf("%d", b); 1013 else 1014 printf("%d,0", b); 1015 } 1016 1017 static char * 1018 preadline(int fd, size_t rlen, off_t off) 1019 { 1020 char *line; 1021 ssize_t nr; 1022 1023 line = xmalloc(rlen + 1); 1024 if ((nr = pread(fd, line, rlen, off)) == -1) 1025 err(2, "preadline"); 1026 if (nr > 0 && line[nr-1] == '\n') 1027 nr--; 1028 line[nr] = '\0'; 1029 return (line); 1030 } 1031 1032 static bool 1033 ignoreline_pattern(char *line) 1034 { 1035 int ret; 1036 1037 ret = regexec(&ignore_re, line, 0, NULL, 0); 1038 free(line); 1039 return (ret == 0); /* if it matched, it should be ignored. */ 1040 } 1041 1042 static bool 1043 ignoreline(char *line, bool skip_blanks) 1044 { 1045 1046 if (ignore_pats != NULL && skip_blanks) 1047 return (ignoreline_pattern(line) || *line == '\0'); 1048 if (ignore_pats != NULL) 1049 return (ignoreline_pattern(line)); 1050 if (skip_blanks) 1051 return (*line == '\0'); 1052 /* No ignore criteria specified */ 1053 return (false); 1054 } 1055 1056 /* 1057 * Indicate that there is a difference between lines a and b of the from file 1058 * to get to lines c to d of the to file. If a is greater then b then there 1059 * are no lines in the from file involved and this means that there were 1060 * lines appended (beginning at b). If c is greater than d then there are 1061 * lines missing from the to file. 1062 */ 1063 static void 1064 change(char *file1, FILE *f1, char *file2, FILE *f2, int a, int b, int c, int d, 1065 int *pflags) 1066 { 1067 static size_t max_context = 64; 1068 long curpos; 1069 int i, nc; 1070 const char *walk; 1071 bool skip_blanks; 1072 1073 skip_blanks = (*pflags & D_SKIPBLANKLINES); 1074 restart: 1075 if ((diff_format != D_IFDEF || diff_format == D_GFORMAT) && 1076 a > b && c > d) 1077 return; 1078 if (ignore_pats != NULL || skip_blanks) { 1079 char *line; 1080 /* 1081 * All lines in the change, insert, or delete must 1082 * match an ignore pattern for the change to be 1083 * ignored. 1084 */ 1085 if (a <= b) { /* Changes and deletes. */ 1086 for (i = a; i <= b; i++) { 1087 line = preadline(fileno(f1), 1088 ixold[i] - ixold[i - 1], ixold[i - 1]); 1089 if (!ignoreline(line, skip_blanks)) 1090 goto proceed; 1091 } 1092 } 1093 if (a > b || c <= d) { /* Changes and inserts. */ 1094 for (i = c; i <= d; i++) { 1095 line = preadline(fileno(f2), 1096 ixnew[i] - ixnew[i - 1], ixnew[i - 1]); 1097 if (!ignoreline(line, skip_blanks)) 1098 goto proceed; 1099 } 1100 } 1101 return; 1102 } 1103 proceed: 1104 if (*pflags & D_HEADER && diff_format != D_BRIEF) { 1105 printf("%s %s %s\n", diffargs, file1, file2); 1106 *pflags &= ~D_HEADER; 1107 } 1108 if (diff_format == D_CONTEXT || diff_format == D_UNIFIED) { 1109 /* 1110 * Allocate change records as needed. 1111 */ 1112 if (context_vec_ptr == context_vec_end - 1) { 1113 ptrdiff_t offset = context_vec_ptr - context_vec_start; 1114 max_context <<= 1; 1115 context_vec_start = xreallocarray(context_vec_start, 1116 max_context, sizeof(*context_vec_start)); 1117 context_vec_end = context_vec_start + max_context; 1118 context_vec_ptr = context_vec_start + offset; 1119 } 1120 if (anychange == 0) { 1121 /* 1122 * Print the context/unidiff header first time through. 1123 */ 1124 print_header(file1, file2); 1125 anychange = 1; 1126 } else if (a > context_vec_ptr->b + (2 * diff_context) + 1 && 1127 c > context_vec_ptr->d + (2 * diff_context) + 1) { 1128 /* 1129 * If this change is more than 'diff_context' lines from the 1130 * previous change, dump the record and reset it. 1131 */ 1132 if (diff_format == D_CONTEXT) 1133 dump_context_vec(f1, f2, *pflags); 1134 else 1135 dump_unified_vec(f1, f2, *pflags); 1136 } 1137 context_vec_ptr++; 1138 context_vec_ptr->a = a; 1139 context_vec_ptr->b = b; 1140 context_vec_ptr->c = c; 1141 context_vec_ptr->d = d; 1142 return; 1143 } 1144 if (anychange == 0) 1145 anychange = 1; 1146 switch (diff_format) { 1147 case D_BRIEF: 1148 return; 1149 case D_NORMAL: 1150 case D_EDIT: 1151 range(a, b, ","); 1152 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1153 if (diff_format == D_NORMAL) 1154 range(c, d, ","); 1155 printf("\n"); 1156 break; 1157 case D_REVERSE: 1158 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1159 range(a, b, " "); 1160 printf("\n"); 1161 break; 1162 case D_NREVERSE: 1163 if (a > b) 1164 printf("a%d %d\n", b, d - c + 1); 1165 else { 1166 printf("d%d %d\n", a, b - a + 1); 1167 if (!(c > d)) 1168 /* add changed lines */ 1169 printf("a%d %d\n", b, d - c + 1); 1170 } 1171 break; 1172 } 1173 if (diff_format == D_GFORMAT) { 1174 curpos = ftell(f1); 1175 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1176 nc = ixold[a > b ? b : a - 1] - curpos; 1177 for (i = 0; i < nc; i++) 1178 printf("%c", getc(f1)); 1179 for (walk = group_format; *walk != '\0'; walk++) { 1180 if (*walk == '%') { 1181 walk++; 1182 switch (*walk) { 1183 case '<': 1184 fetch(ixold, a, b, f1, '<', 1, *pflags); 1185 break; 1186 case '>': 1187 fetch(ixnew, c, d, f2, '>', 0, *pflags); 1188 break; 1189 default: 1190 printf("%%%c", *walk); 1191 break; 1192 } 1193 continue; 1194 } 1195 printf("%c", *walk); 1196 } 1197 } 1198 if (diff_format == D_SIDEBYSIDE) { 1199 if (a > b) { 1200 print_space(0, hw + padding , *pflags); 1201 } else { 1202 nc = fetch(ixold, a, b, f1, '\0', 1, *pflags); 1203 print_space(nc, hw - nc + padding, *pflags); 1204 } 1205 printf("%c", (a>b)? '>' : ((c>d)? '<' : '|')); 1206 print_space(hw + padding + 1 , padding, *pflags); 1207 fetch(ixnew, c, d, f2, '\0', 0, *pflags); 1208 printf("\n"); 1209 } 1210 if (diff_format == D_NORMAL || diff_format == D_IFDEF) { 1211 fetch(ixold, a, b, f1, '<', 1, *pflags); 1212 if (a <= b && c <= d && diff_format == D_NORMAL) 1213 printf("---\n"); 1214 } 1215 if (diff_format != D_GFORMAT && diff_format != D_SIDEBYSIDE) 1216 fetch(ixnew, c, d, f2, diff_format == D_NORMAL ? '>' : '\0', 0, *pflags); 1217 if (edoffset != 0 && diff_format == D_EDIT) { 1218 /* 1219 * A non-zero edoffset value for D_EDIT indicates that the 1220 * last line printed was a bare dot (".") that has been 1221 * escaped as ".." to prevent ed(1) from misinterpreting 1222 * it. We have to add a substitute command to change this 1223 * back and restart where we left off. 1224 */ 1225 printf(".\n"); 1226 printf("%ds/.//\n", a + edoffset - 1); 1227 b = a + edoffset - 1; 1228 a = b + 1; 1229 c += edoffset; 1230 goto restart; 1231 } 1232 if ((diff_format == D_EDIT || diff_format == D_REVERSE) && c <= d) 1233 printf(".\n"); 1234 if (inifdef) { 1235 printf("#endif /* %s */\n", ifdefname); 1236 inifdef = 0; 1237 } 1238 } 1239 1240 static int 1241 fetch(long *f, int a, int b, FILE *lb, int ch, int oldfile, int flags) 1242 { 1243 int i, j, c, lastc, col, nc, newcol; 1244 1245 edoffset = 0; 1246 nc = 0; 1247 /* 1248 * When doing #ifdef's, copy down to current line 1249 * if this is the first file, so that stuff makes it to output. 1250 */ 1251 if ((diff_format == D_IFDEF) && oldfile) { 1252 long curpos = ftell(lb); 1253 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1254 nc = f[a > b ? b : a - 1] - curpos; 1255 for (i = 0; i < nc; i++) 1256 printf("%c", getc(lb)); 1257 } 1258 if (a > b) 1259 return (0); 1260 if (diff_format == D_IFDEF) { 1261 if (inifdef) { 1262 printf("#else /* %s%s */\n", 1263 oldfile == 1 ? "!" : "", ifdefname); 1264 } else { 1265 if (oldfile) 1266 printf("#ifndef %s\n", ifdefname); 1267 else 1268 printf("#ifdef %s\n", ifdefname); 1269 } 1270 inifdef = 1 + oldfile; 1271 } 1272 for (i = a; i <= b; i++) { 1273 fseek(lb, f[i - 1], SEEK_SET); 1274 nc = (f[i] - f[i - 1]); 1275 if (diff_format == D_SIDEBYSIDE && hw < nc) 1276 nc = hw; 1277 if ((diff_format != D_IFDEF && diff_format != D_GFORMAT) && 1278 ch != '\0') { 1279 printf("%c", ch); 1280 if (Tflag && (diff_format == D_NORMAL || 1281 diff_format == D_CONTEXT || 1282 diff_format == D_UNIFIED)) 1283 printf("\t"); 1284 else if (diff_format != D_UNIFIED) 1285 printf(" "); 1286 } 1287 col = 0; 1288 for (j = 0, lastc = '\0'; j < nc; j++, lastc = c) { 1289 c = getc(lb); 1290 if (flags & D_STRIPCR && c == '\r') { 1291 if ((c = getc(lb)) == '\n') 1292 j++; 1293 else { 1294 ungetc(c, lb); 1295 c = '\r'; 1296 } 1297 } 1298 if (c == EOF) { 1299 if (diff_format == D_EDIT || 1300 diff_format == D_REVERSE || 1301 diff_format == D_NREVERSE) 1302 warnx("No newline at end of file"); 1303 else 1304 printf("\n\\ No newline at end of " 1305 "file\n"); 1306 return col; 1307 } 1308 /* 1309 * when using --side-by-side, col needs to be increased 1310 * in any case to keep the columns aligned 1311 */ 1312 if (c == '\t') { 1313 if (flags & D_EXPANDTABS) { 1314 newcol = ((col/tabsize)+1)*tabsize; 1315 do { 1316 if (diff_format == D_SIDEBYSIDE) 1317 j++; 1318 printf(" "); 1319 } while (++col < newcol && j < nc); 1320 } else { 1321 if (diff_format == D_SIDEBYSIDE) { 1322 if ((j + tabsize) > nc) { 1323 printf("%*s", 1324 nc - j,""); 1325 j = col = nc; 1326 } else { 1327 printf("\t"); 1328 col += tabsize - 1; 1329 j += tabsize - 1; 1330 } 1331 } else { 1332 printf("\t"); 1333 col++; 1334 } 1335 } 1336 } else { 1337 if (diff_format == D_EDIT && j == 1 && c == '\n' 1338 && lastc == '.') { 1339 /* 1340 * Don't print a bare "." line 1341 * since that will confuse ed(1). 1342 * Print ".." instead and set the, 1343 * global variable edoffset to an 1344 * offset from which to restart. 1345 * The caller must check the value 1346 * of edoffset 1347 */ 1348 printf(".\n"); 1349 edoffset = i - a + 1; 1350 return edoffset; 1351 } 1352 /* when side-by-side, do not print a newline */ 1353 if (diff_format != D_SIDEBYSIDE || c != '\n') { 1354 printf("%c", c); 1355 col++; 1356 } 1357 } 1358 } 1359 } 1360 return col; 1361 } 1362 1363 /* 1364 * Hash function taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. 1365 */ 1366 static enum readhash 1367 readhash(FILE *f, int flags, unsigned *hash) 1368 { 1369 int i, t, space; 1370 unsigned sum; 1371 1372 sum = 1; 1373 space = 0; 1374 for (i = 0;;) { 1375 switch (t = getc(f)) { 1376 case '\0': 1377 if ((flags & D_FORCEASCII) == 0) 1378 return (RH_BINARY); 1379 case '\r': 1380 if (flags & D_STRIPCR) { 1381 t = getc(f); 1382 if (t == '\n') 1383 break; 1384 ungetc(t, f); 1385 } 1386 /* FALLTHROUGH */ 1387 case '\t': 1388 case '\v': 1389 case '\f': 1390 case ' ': 1391 if ((flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) != 0) { 1392 space++; 1393 continue; 1394 } 1395 /* FALLTHROUGH */ 1396 default: 1397 if (space && (flags & D_IGNOREBLANKS) == 0) { 1398 i++; 1399 space = 0; 1400 } 1401 sum = sum * 127 + chrtran(t); 1402 i++; 1403 continue; 1404 case EOF: 1405 if (i == 0) 1406 return (RH_EOF); 1407 /* FALLTHROUGH */ 1408 case '\n': 1409 break; 1410 } 1411 break; 1412 } 1413 *hash = sum; 1414 return (RH_OK); 1415 } 1416 1417 static int 1418 asciifile(FILE *f) 1419 { 1420 unsigned char buf[BUFSIZ]; 1421 size_t cnt; 1422 1423 if (f == NULL) 1424 return (1); 1425 1426 rewind(f); 1427 cnt = fread(buf, 1, sizeof(buf), f); 1428 return (memchr(buf, '\0', cnt) == NULL); 1429 } 1430 1431 #define begins_with(s, pre) (strncmp(s, pre, sizeof(pre)-1) == 0) 1432 1433 static char * 1434 match_function(const long *f, int pos, FILE *fp) 1435 { 1436 unsigned char buf[FUNCTION_CONTEXT_SIZE]; 1437 size_t nc; 1438 int last = lastline; 1439 const char *state = NULL; 1440 1441 lastline = pos; 1442 while (pos > last) { 1443 fseek(fp, f[pos - 1], SEEK_SET); 1444 nc = f[pos] - f[pos - 1]; 1445 if (nc >= sizeof(buf)) 1446 nc = sizeof(buf) - 1; 1447 nc = fread(buf, 1, nc, fp); 1448 if (nc > 0) { 1449 buf[nc] = '\0'; 1450 buf[strcspn(buf, "\n")] = '\0'; 1451 if (isalpha(buf[0]) || buf[0] == '_' || buf[0] == '$') { 1452 if (begins_with(buf, "private:")) { 1453 if (!state) 1454 state = " (private)"; 1455 } else if (begins_with(buf, "protected:")) { 1456 if (!state) 1457 state = " (protected)"; 1458 } else if (begins_with(buf, "public:")) { 1459 if (!state) 1460 state = " (public)"; 1461 } else { 1462 strlcpy(lastbuf, buf, sizeof lastbuf); 1463 if (state) 1464 strlcat(lastbuf, state, 1465 sizeof lastbuf); 1466 lastmatchline = pos; 1467 return lastbuf; 1468 } 1469 } 1470 } 1471 pos--; 1472 } 1473 return lastmatchline > 0 ? lastbuf : NULL; 1474 } 1475 1476 /* dump accumulated "context" diff changes */ 1477 static void 1478 dump_context_vec(FILE *f1, FILE *f2, int flags) 1479 { 1480 struct context_vec *cvp = context_vec_start; 1481 int lowa, upb, lowc, upd, do_output; 1482 int a, b, c, d; 1483 char ch, *f; 1484 1485 if (context_vec_start > context_vec_ptr) 1486 return; 1487 1488 b = d = 0; /* gcc */ 1489 lowa = MAX(1, cvp->a - diff_context); 1490 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1491 lowc = MAX(1, cvp->c - diff_context); 1492 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1493 1494 printf("***************"); 1495 if ((flags & D_PROTOTYPE)) { 1496 f = match_function(ixold, lowa-1, f1); 1497 if (f != NULL) 1498 printf(" %s", f); 1499 } 1500 printf("\n*** "); 1501 range(lowa, upb, ","); 1502 printf(" ****\n"); 1503 1504 /* 1505 * Output changes to the "old" file. The first loop suppresses 1506 * output if there were no changes to the "old" file (we'll see 1507 * the "old" lines as context in the "new" list). 1508 */ 1509 do_output = 0; 1510 for (; cvp <= context_vec_ptr; cvp++) 1511 if (cvp->a <= cvp->b) { 1512 cvp = context_vec_start; 1513 do_output++; 1514 break; 1515 } 1516 if (do_output) { 1517 while (cvp <= context_vec_ptr) { 1518 a = cvp->a; 1519 b = cvp->b; 1520 c = cvp->c; 1521 d = cvp->d; 1522 1523 if (a <= b && c <= d) 1524 ch = 'c'; 1525 else 1526 ch = (a <= b) ? 'd' : 'a'; 1527 1528 if (ch == 'a') 1529 fetch(ixold, lowa, b, f1, ' ', 0, flags); 1530 else { 1531 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1532 fetch(ixold, a, b, f1, 1533 ch == 'c' ? '!' : '-', 0, flags); 1534 } 1535 lowa = b + 1; 1536 cvp++; 1537 } 1538 fetch(ixold, b + 1, upb, f1, ' ', 0, flags); 1539 } 1540 /* output changes to the "new" file */ 1541 printf("--- "); 1542 range(lowc, upd, ","); 1543 printf(" ----\n"); 1544 1545 do_output = 0; 1546 for (cvp = context_vec_start; cvp <= context_vec_ptr; cvp++) 1547 if (cvp->c <= cvp->d) { 1548 cvp = context_vec_start; 1549 do_output++; 1550 break; 1551 } 1552 if (do_output) { 1553 while (cvp <= context_vec_ptr) { 1554 a = cvp->a; 1555 b = cvp->b; 1556 c = cvp->c; 1557 d = cvp->d; 1558 1559 if (a <= b && c <= d) 1560 ch = 'c'; 1561 else 1562 ch = (a <= b) ? 'd' : 'a'; 1563 1564 if (ch == 'd') 1565 fetch(ixnew, lowc, d, f2, ' ', 0, flags); 1566 else { 1567 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1568 fetch(ixnew, c, d, f2, 1569 ch == 'c' ? '!' : '+', 0, flags); 1570 } 1571 lowc = d + 1; 1572 cvp++; 1573 } 1574 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1575 } 1576 context_vec_ptr = context_vec_start - 1; 1577 } 1578 1579 /* dump accumulated "unified" diff changes */ 1580 static void 1581 dump_unified_vec(FILE *f1, FILE *f2, int flags) 1582 { 1583 struct context_vec *cvp = context_vec_start; 1584 int lowa, upb, lowc, upd; 1585 int a, b, c, d; 1586 char ch, *f; 1587 1588 if (context_vec_start > context_vec_ptr) 1589 return; 1590 1591 b = d = 0; /* gcc */ 1592 lowa = MAX(1, cvp->a - diff_context); 1593 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1594 lowc = MAX(1, cvp->c - diff_context); 1595 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1596 1597 printf("@@ -"); 1598 uni_range(lowa, upb); 1599 printf(" +"); 1600 uni_range(lowc, upd); 1601 printf(" @@"); 1602 if ((flags & D_PROTOTYPE)) { 1603 f = match_function(ixold, lowa-1, f1); 1604 if (f != NULL) 1605 printf(" %s", f); 1606 } 1607 printf("\n"); 1608 1609 /* 1610 * Output changes in "unified" diff format--the old and new lines 1611 * are printed together. 1612 */ 1613 for (; cvp <= context_vec_ptr; cvp++) { 1614 a = cvp->a; 1615 b = cvp->b; 1616 c = cvp->c; 1617 d = cvp->d; 1618 1619 /* 1620 * c: both new and old changes 1621 * d: only changes in the old file 1622 * a: only changes in the new file 1623 */ 1624 if (a <= b && c <= d) 1625 ch = 'c'; 1626 else 1627 ch = (a <= b) ? 'd' : 'a'; 1628 1629 switch (ch) { 1630 case 'c': 1631 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1632 fetch(ixold, a, b, f1, '-', 0, flags); 1633 fetch(ixnew, c, d, f2, '+', 0, flags); 1634 break; 1635 case 'd': 1636 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1637 fetch(ixold, a, b, f1, '-', 0, flags); 1638 break; 1639 case 'a': 1640 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1641 fetch(ixnew, c, d, f2, '+', 0, flags); 1642 break; 1643 } 1644 lowa = b + 1; 1645 lowc = d + 1; 1646 } 1647 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1648 1649 context_vec_ptr = context_vec_start - 1; 1650 } 1651 1652 static void 1653 print_header(const char *file1, const char *file2) 1654 { 1655 const char *time_format; 1656 char buf1[256]; 1657 char buf2[256]; 1658 char end1[10]; 1659 char end2[10]; 1660 struct tm tm1, tm2, *tm_ptr1, *tm_ptr2; 1661 int nsec1 = stb1.st_mtim.tv_nsec; 1662 int nsec2 = stb2.st_mtim.tv_nsec; 1663 1664 time_format = "%Y-%m-%d %H:%M:%S"; 1665 1666 if (cflag) 1667 time_format = "%c"; 1668 tm_ptr1 = localtime_r(&stb1.st_mtime, &tm1); 1669 tm_ptr2 = localtime_r(&stb2.st_mtime, &tm2); 1670 strftime(buf1, 256, time_format, tm_ptr1); 1671 strftime(buf2, 256, time_format, tm_ptr2); 1672 if (!cflag) { 1673 strftime(end1, 10, "%z", tm_ptr1); 1674 strftime(end2, 10, "%z", tm_ptr2); 1675 sprintf(buf1, "%s.%.9d %s", buf1, nsec1, end1); 1676 sprintf(buf2, "%s.%.9d %s", buf2, nsec2, end2); 1677 } 1678 if (label[0] != NULL) 1679 printf("%s %s\n", diff_format == D_CONTEXT ? "***" : "---", 1680 label[0]); 1681 else 1682 printf("%s %s\t%s\n", diff_format == D_CONTEXT ? "***" : "---", 1683 file1, buf1); 1684 if (label[1] != NULL) 1685 printf("%s %s\n", diff_format == D_CONTEXT ? "---" : "+++", 1686 label[1]); 1687 else 1688 printf("%s %s\t%s\n", diff_format == D_CONTEXT ? "---" : "+++", 1689 file2, buf2); 1690 } 1691 1692 /* 1693 * Prints n number of space characters either by using tab 1694 * or single space characters. 1695 * nc is the preceding number of characters 1696 */ 1697 static void 1698 print_space(int nc, int n, int flags) { 1699 int i, col; 1700 1701 col = n; 1702 if ((flags & D_EXPANDTABS) == 0) { 1703 /* first tabstop may be closer than tabsize */ 1704 i = tabsize - (nc % tabsize); 1705 while (col >= tabsize) { 1706 printf("\t"); 1707 col -= i; 1708 i = tabsize; 1709 } 1710 } 1711 printf("%*s", col, ""); 1712 } 1713