1 /* $OpenBSD: diffreg.c,v 1.91 2016/03/01 20:57:35 natano 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 #define diff_output printf 184 static FILE *opentemp(const char *); 185 static void output(char *, FILE *, char *, FILE *, int); 186 static void check(FILE *, FILE *, int); 187 static void range(int, int, const char *); 188 static void uni_range(int, int); 189 static void dump_context_vec(FILE *, FILE *, int); 190 static void dump_unified_vec(FILE *, FILE *, int); 191 static void prepare(int, FILE *, size_t, int); 192 static void prune(void); 193 static void equiv(struct line *, int, struct line *, int, int *); 194 static void unravel(int); 195 static void unsort(struct line *, int, int *); 196 static void change(char *, FILE *, char *, FILE *, int, int, int, int, int *); 197 static void sort(struct line *, int); 198 static void print_header(const char *, const char *); 199 static bool ignoreline_pattern(char *); 200 static bool ignoreline(char *, bool); 201 static int asciifile(FILE *); 202 static int fetch(long *, int, int, FILE *, int, int, int); 203 static int newcand(int, int, int); 204 static int search(int *, int, int); 205 static int skipline(FILE *); 206 static int isqrt(int); 207 static int stone(int *, int, int *, int *, int); 208 static int readhash(FILE *, int); 209 static int files_differ(FILE *, FILE *, int); 210 static char *match_function(const long *, int, FILE *); 211 static char *preadline(int, size_t, off_t); 212 213 static int *J; /* will be overlaid on class */ 214 static int *class; /* will be overlaid on file[0] */ 215 static int *klist; /* will be overlaid on file[0] after class */ 216 static int *member; /* will be overlaid on file[1] */ 217 static int clen; 218 static int inifdef; /* whether or not we are in a #ifdef block */ 219 static int len[2]; 220 static int pref, suff; /* length of prefix and suffix */ 221 static int slen[2]; 222 static int anychange; 223 static long *ixnew; /* will be overlaid on file[1] */ 224 static long *ixold; /* will be overlaid on klist */ 225 static struct cand *clist; /* merely a free storage pot for candidates */ 226 static int clistlen; /* the length of clist */ 227 static struct line *sfile[2]; /* shortened by pruning common prefix/suffix */ 228 static int (*chrtran)(int); /* translation table for case-folding */ 229 static struct context_vec *context_vec_start; 230 static struct context_vec *context_vec_end; 231 static struct context_vec *context_vec_ptr; 232 233 #define FUNCTION_CONTEXT_SIZE 55 234 static char lastbuf[FUNCTION_CONTEXT_SIZE]; 235 static int lastline; 236 static int lastmatchline; 237 238 static int 239 clow2low(int c) 240 { 241 242 return (c); 243 } 244 245 static int 246 cup2low(int c) 247 { 248 249 return tolower(c); 250 } 251 252 int 253 diffreg(char *file1, char *file2, int flags, int capsicum) 254 { 255 FILE *f1, *f2; 256 int i, rval; 257 struct pr *pr = NULL; 258 cap_rights_t rights_ro; 259 260 f1 = f2 = NULL; 261 rval = D_SAME; 262 anychange = 0; 263 lastline = 0; 264 lastmatchline = 0; 265 context_vec_ptr = context_vec_start - 1; 266 if (flags & D_IGNORECASE) 267 chrtran = cup2low; 268 else 269 chrtran = clow2low; 270 if (S_ISDIR(stb1.st_mode) != S_ISDIR(stb2.st_mode)) 271 return (S_ISDIR(stb1.st_mode) ? D_MISMATCH1 : D_MISMATCH2); 272 if (strcmp(file1, "-") == 0 && strcmp(file2, "-") == 0) 273 goto closem; 274 275 if (flags & D_EMPTY1) 276 f1 = fopen(_PATH_DEVNULL, "r"); 277 else { 278 if (!S_ISREG(stb1.st_mode)) { 279 if ((f1 = opentemp(file1)) == NULL || 280 fstat(fileno(f1), &stb1) < 0) { 281 warn("%s", file1); 282 status |= 2; 283 goto closem; 284 } 285 } else if (strcmp(file1, "-") == 0) 286 f1 = stdin; 287 else 288 f1 = fopen(file1, "r"); 289 } 290 if (f1 == NULL) { 291 warn("%s", file1); 292 status |= 2; 293 goto closem; 294 } 295 296 if (flags & D_EMPTY2) 297 f2 = fopen(_PATH_DEVNULL, "r"); 298 else { 299 if (!S_ISREG(stb2.st_mode)) { 300 if ((f2 = opentemp(file2)) == NULL || 301 fstat(fileno(f2), &stb2) < 0) { 302 warn("%s", file2); 303 status |= 2; 304 goto closem; 305 } 306 } else if (strcmp(file2, "-") == 0) 307 f2 = stdin; 308 else 309 f2 = fopen(file2, "r"); 310 } 311 if (f2 == NULL) { 312 warn("%s", file2); 313 status |= 2; 314 goto closem; 315 } 316 317 if (lflag) 318 pr = start_pr(file1, file2); 319 320 if (capsicum) { 321 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); 322 if (cap_rights_limit(fileno(f1), &rights_ro) < 0 323 && errno != ENOSYS) 324 err(2, "unable to limit rights on: %s", file1); 325 if (cap_rights_limit(fileno(f2), &rights_ro) < 0 && 326 errno != ENOSYS) 327 err(2, "unable to limit rights on: %s", file2); 328 if (fileno(f1) == STDIN_FILENO || fileno(f2) == STDIN_FILENO) { 329 /* stding has already been limited */ 330 if (caph_limit_stderr() == -1) 331 err(2, "unable to limit stderr"); 332 if (caph_limit_stdout() == -1) 333 err(2, "unable to limit stdout"); 334 } else if (caph_limit_stdio() == -1) 335 err(2, "unable to limit stdio"); 336 337 caph_cache_catpages(); 338 caph_cache_tzdata(); 339 if (caph_enter() < 0) 340 err(2, "unable to enter capability mode"); 341 } 342 343 switch (files_differ(f1, f2, flags)) { 344 case 0: 345 goto closem; 346 case 1: 347 break; 348 default: 349 /* error */ 350 status |= 2; 351 goto closem; 352 } 353 354 if ((flags & D_FORCEASCII) == 0 && 355 (!asciifile(f1) || !asciifile(f2))) { 356 rval = D_BINARY; 357 status |= 1; 358 goto closem; 359 } 360 prepare(0, f1, stb1.st_size, flags); 361 prepare(1, f2, stb2.st_size, flags); 362 363 prune(); 364 sort(sfile[0], slen[0]); 365 sort(sfile[1], slen[1]); 366 367 member = (int *)file[1]; 368 equiv(sfile[0], slen[0], sfile[1], slen[1], member); 369 member = xreallocarray(member, slen[1] + 2, sizeof(*member)); 370 371 class = (int *)file[0]; 372 unsort(sfile[0], slen[0], class); 373 class = xreallocarray(class, slen[0] + 2, sizeof(*class)); 374 375 klist = xcalloc(slen[0] + 2, sizeof(*klist)); 376 clen = 0; 377 clistlen = 100; 378 clist = xcalloc(clistlen, sizeof(*clist)); 379 i = stone(class, slen[0], member, klist, flags); 380 free(member); 381 free(class); 382 383 J = xreallocarray(J, len[0] + 2, sizeof(*J)); 384 unravel(klist[i]); 385 free(clist); 386 free(klist); 387 388 ixold = xreallocarray(ixold, len[0] + 2, sizeof(*ixold)); 389 ixnew = xreallocarray(ixnew, len[1] + 2, sizeof(*ixnew)); 390 check(f1, f2, flags); 391 output(file1, f1, file2, f2, flags); 392 if (pr != NULL) 393 stop_pr(pr); 394 395 closem: 396 if (anychange) { 397 status |= 1; 398 if (rval == D_SAME) 399 rval = D_DIFFER; 400 } 401 if (f1 != NULL) 402 fclose(f1); 403 if (f2 != NULL) 404 fclose(f2); 405 406 return (rval); 407 } 408 409 /* 410 * Check to see if the given files differ. 411 * Returns 0 if they are the same, 1 if different, and -1 on error. 412 * XXX - could use code from cmp(1) [faster] 413 */ 414 static int 415 files_differ(FILE *f1, FILE *f2, int flags) 416 { 417 char buf1[BUFSIZ], buf2[BUFSIZ]; 418 size_t i, j; 419 420 if ((flags & (D_EMPTY1|D_EMPTY2)) || stb1.st_size != stb2.st_size || 421 (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)) 422 return (1); 423 for (;;) { 424 i = fread(buf1, 1, sizeof(buf1), f1); 425 j = fread(buf2, 1, sizeof(buf2), f2); 426 if ((!i && ferror(f1)) || (!j && ferror(f2))) 427 return (-1); 428 if (i != j) 429 return (1); 430 if (i == 0) 431 return (0); 432 if (memcmp(buf1, buf2, i) != 0) 433 return (1); 434 } 435 } 436 437 static FILE * 438 opentemp(const char *f) 439 { 440 char buf[BUFSIZ], tempfile[PATH_MAX]; 441 ssize_t nread; 442 int ifd, ofd; 443 444 if (strcmp(f, "-") == 0) 445 ifd = STDIN_FILENO; 446 else if ((ifd = open(f, O_RDONLY, 0644)) < 0) 447 return (NULL); 448 449 (void)strlcpy(tempfile, _PATH_TMP "/diff.XXXXXXXX", sizeof(tempfile)); 450 451 if ((ofd = mkstemp(tempfile)) < 0) { 452 close(ifd); 453 return (NULL); 454 } 455 unlink(tempfile); 456 while ((nread = read(ifd, buf, BUFSIZ)) > 0) { 457 if (write(ofd, buf, nread) != nread) { 458 close(ifd); 459 close(ofd); 460 return (NULL); 461 } 462 } 463 close(ifd); 464 lseek(ofd, (off_t)0, SEEK_SET); 465 return (fdopen(ofd, "r")); 466 } 467 468 char * 469 splice(char *dir, char *path) 470 { 471 char *tail, *buf; 472 size_t dirlen; 473 474 dirlen = strlen(dir); 475 while (dirlen != 0 && dir[dirlen - 1] == '/') 476 dirlen--; 477 if ((tail = strrchr(path, '/')) == NULL) 478 tail = path; 479 else 480 tail++; 481 xasprintf(&buf, "%.*s/%s", (int)dirlen, dir, tail); 482 return (buf); 483 } 484 485 static void 486 prepare(int i, FILE *fd, size_t filesize, int flags) 487 { 488 struct line *p; 489 int h; 490 size_t sz, j; 491 492 rewind(fd); 493 494 sz = MIN(filesize, SIZE_MAX) / 25; 495 if (sz < 100) 496 sz = 100; 497 498 p = xcalloc(sz + 3, sizeof(*p)); 499 for (j = 0; (h = readhash(fd, flags));) { 500 if (j == sz) { 501 sz = sz * 3 / 2; 502 p = xreallocarray(p, sz + 3, sizeof(*p)); 503 } 504 p[++j].value = h; 505 } 506 len[i] = j; 507 file[i] = p; 508 } 509 510 static void 511 prune(void) 512 { 513 int i, j; 514 515 for (pref = 0; pref < len[0] && pref < len[1] && 516 file[0][pref + 1].value == file[1][pref + 1].value; 517 pref++) 518 ; 519 for (suff = 0; suff < len[0] - pref && suff < len[1] - pref && 520 file[0][len[0] - suff].value == file[1][len[1] - suff].value; 521 suff++) 522 ; 523 for (j = 0; j < 2; j++) { 524 sfile[j] = file[j] + pref; 525 slen[j] = len[j] - pref - suff; 526 for (i = 0; i <= slen[j]; i++) 527 sfile[j][i].serial = i; 528 } 529 } 530 531 static void 532 equiv(struct line *a, int n, struct line *b, int m, int *c) 533 { 534 int i, j; 535 536 i = j = 1; 537 while (i <= n && j <= m) { 538 if (a[i].value < b[j].value) 539 a[i++].value = 0; 540 else if (a[i].value == b[j].value) 541 a[i++].value = j; 542 else 543 j++; 544 } 545 while (i <= n) 546 a[i++].value = 0; 547 b[m + 1].value = 0; 548 j = 0; 549 while (++j <= m) { 550 c[j] = -b[j].serial; 551 while (b[j + 1].value == b[j].value) { 552 j++; 553 c[j] = b[j].serial; 554 } 555 } 556 c[j] = -1; 557 } 558 559 /* Code taken from ping.c */ 560 static int 561 isqrt(int n) 562 { 563 int y, x = 1; 564 565 if (n == 0) 566 return (0); 567 568 do { /* newton was a stinker */ 569 y = x; 570 x = n / x; 571 x += y; 572 x /= 2; 573 } while ((x - y) > 1 || (x - y) < -1); 574 575 return (x); 576 } 577 578 static int 579 stone(int *a, int n, int *b, int *c, int flags) 580 { 581 int i, k, y, j, l; 582 int oldc, tc, oldl, sq; 583 u_int numtries, bound; 584 585 if (flags & D_MINIMAL) 586 bound = UINT_MAX; 587 else { 588 sq = isqrt(n); 589 bound = MAX(256, sq); 590 } 591 592 k = 0; 593 c[0] = newcand(0, 0, 0); 594 for (i = 1; i <= n; i++) { 595 j = a[i]; 596 if (j == 0) 597 continue; 598 y = -b[j]; 599 oldl = 0; 600 oldc = c[0]; 601 numtries = 0; 602 do { 603 if (y <= clist[oldc].y) 604 continue; 605 l = search(c, k, y); 606 if (l != oldl + 1) 607 oldc = c[l - 1]; 608 if (l <= k) { 609 if (clist[c[l]].y <= y) 610 continue; 611 tc = c[l]; 612 c[l] = newcand(i, y, oldc); 613 oldc = tc; 614 oldl = l; 615 numtries++; 616 } else { 617 c[l] = newcand(i, y, oldc); 618 k++; 619 break; 620 } 621 } while ((y = b[++j]) > 0 && numtries < bound); 622 } 623 return (k); 624 } 625 626 static int 627 newcand(int x, int y, int pred) 628 { 629 struct cand *q; 630 631 if (clen == clistlen) { 632 clistlen = clistlen * 11 / 10; 633 clist = xreallocarray(clist, clistlen, sizeof(*clist)); 634 } 635 q = clist + clen; 636 q->x = x; 637 q->y = y; 638 q->pred = pred; 639 return (clen++); 640 } 641 642 static int 643 search(int *c, int k, int y) 644 { 645 int i, j, l, t; 646 647 if (clist[c[k]].y < y) /* quick look for typical case */ 648 return (k + 1); 649 i = 0; 650 j = k + 1; 651 for (;;) { 652 l = (i + j) / 2; 653 if (l <= i) 654 break; 655 t = clist[c[l]].y; 656 if (t > y) 657 j = l; 658 else if (t < y) 659 i = l; 660 else 661 return (l); 662 } 663 return (l + 1); 664 } 665 666 static void 667 unravel(int p) 668 { 669 struct cand *q; 670 int i; 671 672 for (i = 0; i <= len[0]; i++) 673 J[i] = i <= pref ? i : 674 i > len[0] - suff ? i + len[1] - len[0] : 0; 675 for (q = clist + p; q->y != 0; q = clist + q->pred) 676 J[q->x + pref] = q->y + pref; 677 } 678 679 /* 680 * Check does double duty: 681 * 1. ferret out any fortuitous correspondences due 682 * to confounding by hashing (which result in "jackpot") 683 * 2. collect random access indexes to the two files 684 */ 685 static void 686 check(FILE *f1, FILE *f2, int flags) 687 { 688 int i, j, jackpot, c, d; 689 long ctold, ctnew; 690 691 rewind(f1); 692 rewind(f2); 693 j = 1; 694 ixold[0] = ixnew[0] = 0; 695 jackpot = 0; 696 ctold = ctnew = 0; 697 for (i = 1; i <= len[0]; i++) { 698 if (J[i] == 0) { 699 ixold[i] = ctold += skipline(f1); 700 continue; 701 } 702 while (j < J[i]) { 703 ixnew[j] = ctnew += skipline(f2); 704 j++; 705 } 706 if (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE|D_STRIPCR)) { 707 for (;;) { 708 c = getc(f1); 709 d = getc(f2); 710 /* 711 * GNU diff ignores a missing newline 712 * in one file for -b or -w. 713 */ 714 if (flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) { 715 if (c == EOF && d == '\n') { 716 ctnew++; 717 break; 718 } else if (c == '\n' && d == EOF) { 719 ctold++; 720 break; 721 } 722 } 723 ctold++; 724 ctnew++; 725 if (flags & D_STRIPCR && (c == '\r' || d == '\r')) { 726 if (c == '\r') { 727 if ((c = getc(f1)) == '\n') { 728 ctold++; 729 } else { 730 ungetc(c, f1); 731 } 732 } 733 if (d == '\r') { 734 if ((d = getc(f2)) == '\n') { 735 ctnew++; 736 } else { 737 ungetc(d, f2); 738 } 739 } 740 break; 741 } 742 if ((flags & D_FOLDBLANKS) && isspace(c) && 743 isspace(d)) { 744 do { 745 if (c == '\n') 746 break; 747 ctold++; 748 } while (isspace(c = getc(f1))); 749 do { 750 if (d == '\n') 751 break; 752 ctnew++; 753 } while (isspace(d = getc(f2))); 754 } else if ((flags & D_IGNOREBLANKS)) { 755 while (isspace(c) && c != '\n') { 756 c = getc(f1); 757 ctold++; 758 } 759 while (isspace(d) && d != '\n') { 760 d = getc(f2); 761 ctnew++; 762 } 763 } 764 if (chrtran(c) != chrtran(d)) { 765 jackpot++; 766 J[i] = 0; 767 if (c != '\n' && c != EOF) 768 ctold += skipline(f1); 769 if (d != '\n' && c != EOF) 770 ctnew += skipline(f2); 771 break; 772 } 773 if (c == '\n' || c == EOF) 774 break; 775 } 776 } else { 777 for (;;) { 778 ctold++; 779 ctnew++; 780 if ((c = getc(f1)) != (d = getc(f2))) { 781 /* jackpot++; */ 782 J[i] = 0; 783 if (c != '\n' && c != EOF) 784 ctold += skipline(f1); 785 if (d != '\n' && c != EOF) 786 ctnew += skipline(f2); 787 break; 788 } 789 if (c == '\n' || c == EOF) 790 break; 791 } 792 } 793 ixold[i] = ctold; 794 ixnew[j] = ctnew; 795 j++; 796 } 797 for (; j <= len[1]; j++) { 798 ixnew[j] = ctnew += skipline(f2); 799 } 800 /* 801 * if (jackpot) 802 * fprintf(stderr, "jackpot\n"); 803 */ 804 } 805 806 /* shellsort CACM #201 */ 807 static void 808 sort(struct line *a, int n) 809 { 810 struct line *ai, *aim, w; 811 int j, m = 0, k; 812 813 if (n == 0) 814 return; 815 for (j = 1; j <= n; j *= 2) 816 m = 2 * j - 1; 817 for (m /= 2; m != 0; m /= 2) { 818 k = n - m; 819 for (j = 1; j <= k; j++) { 820 for (ai = &a[j]; ai > a; ai -= m) { 821 aim = &ai[m]; 822 if (aim < ai) 823 break; /* wraparound */ 824 if (aim->value > ai[0].value || 825 (aim->value == ai[0].value && 826 aim->serial > ai[0].serial)) 827 break; 828 w.value = ai[0].value; 829 ai[0].value = aim->value; 830 aim->value = w.value; 831 w.serial = ai[0].serial; 832 ai[0].serial = aim->serial; 833 aim->serial = w.serial; 834 } 835 } 836 } 837 } 838 839 static void 840 unsort(struct line *f, int l, int *b) 841 { 842 int *a, i; 843 844 a = xcalloc(l + 1, sizeof(*a)); 845 for (i = 1; i <= l; i++) 846 a[f[i].serial] = f[i].value; 847 for (i = 1; i <= l; i++) 848 b[i] = a[i]; 849 free(a); 850 } 851 852 static int 853 skipline(FILE *f) 854 { 855 int i, c; 856 857 for (i = 1; (c = getc(f)) != '\n' && c != EOF; i++) 858 continue; 859 return (i); 860 } 861 862 static void 863 output(char *file1, FILE *f1, char *file2, FILE *f2, int flags) 864 { 865 int m, i0, i1, j0, j1; 866 867 rewind(f1); 868 rewind(f2); 869 m = len[0]; 870 J[0] = 0; 871 J[m + 1] = len[1] + 1; 872 if (diff_format != D_EDIT) { 873 for (i0 = 1; i0 <= m; i0 = i1 + 1) { 874 while (i0 <= m && J[i0] == J[i0 - 1] + 1) 875 i0++; 876 j0 = J[i0 - 1] + 1; 877 i1 = i0 - 1; 878 while (i1 < m && J[i1 + 1] == 0) 879 i1++; 880 j1 = J[i1 + 1] - 1; 881 J[i1] = j1; 882 change(file1, f1, file2, f2, i0, i1, j0, j1, &flags); 883 } 884 } else { 885 for (i0 = m; i0 >= 1; i0 = i1 - 1) { 886 while (i0 >= 1 && J[i0] == J[i0 + 1] - 1 && J[i0] != 0) 887 i0--; 888 j0 = J[i0 + 1] - 1; 889 i1 = i0 + 1; 890 while (i1 > 1 && J[i1 - 1] == 0) 891 i1--; 892 j1 = J[i1 - 1] + 1; 893 J[i1] = j1; 894 change(file1, f1, file2, f2, i1, i0, j1, j0, &flags); 895 } 896 } 897 if (m == 0) 898 change(file1, f1, file2, f2, 1, 0, 1, len[1], &flags); 899 if (diff_format == D_IFDEF || diff_format == D_GFORMAT) { 900 for (;;) { 901 #define c i0 902 if ((c = getc(f1)) == EOF) 903 return; 904 diff_output("%c", c); 905 } 906 #undef c 907 } 908 if (anychange != 0) { 909 if (diff_format == D_CONTEXT) 910 dump_context_vec(f1, f2, flags); 911 else if (diff_format == D_UNIFIED) 912 dump_unified_vec(f1, f2, flags); 913 } 914 } 915 916 static void 917 range(int a, int b, const char *separator) 918 { 919 diff_output("%d", a > b ? b : a); 920 if (a < b) 921 diff_output("%s%d", separator, b); 922 } 923 924 static void 925 uni_range(int a, int b) 926 { 927 if (a < b) 928 diff_output("%d,%d", a, b - a + 1); 929 else if (a == b) 930 diff_output("%d", b); 931 else 932 diff_output("%d,0", b); 933 } 934 935 static char * 936 preadline(int fd, size_t rlen, off_t off) 937 { 938 char *line; 939 ssize_t nr; 940 941 line = xmalloc(rlen + 1); 942 if ((nr = pread(fd, line, rlen, off)) < 0) 943 err(2, "preadline"); 944 if (nr > 0 && line[nr-1] == '\n') 945 nr--; 946 line[nr] = '\0'; 947 return (line); 948 } 949 950 static bool 951 ignoreline_pattern(char *line) 952 { 953 int ret; 954 955 ret = regexec(&ignore_re, line, 0, NULL, 0); 956 free(line); 957 return (ret == 0); /* if it matched, it should be ignored. */ 958 } 959 960 static bool 961 ignoreline(char *line, bool skip_blanks) 962 { 963 964 if (ignore_pats != NULL && skip_blanks) 965 return (ignoreline_pattern(line) || *line == '\0'); 966 if (ignore_pats != NULL) 967 return (ignoreline_pattern(line)); 968 if (skip_blanks) 969 return (*line == '\0'); 970 /* No ignore criteria specified */ 971 return (false); 972 } 973 974 /* 975 * Indicate that there is a difference between lines a and b of the from file 976 * to get to lines c to d of the to file. If a is greater then b then there 977 * are no lines in the from file involved and this means that there were 978 * lines appended (beginning at b). If c is greater than d then there are 979 * lines missing from the to file. 980 */ 981 static void 982 change(char *file1, FILE *f1, char *file2, FILE *f2, int a, int b, int c, int d, 983 int *pflags) 984 { 985 static size_t max_context = 64; 986 long curpos; 987 int i, nc, f; 988 const char *walk; 989 bool skip_blanks; 990 991 skip_blanks = (*pflags & D_SKIPBLANKLINES); 992 restart: 993 if ((diff_format != D_IFDEF || diff_format == D_GFORMAT) && 994 a > b && c > d) 995 return; 996 if (ignore_pats != NULL || skip_blanks) { 997 char *line; 998 /* 999 * All lines in the change, insert, or delete must 1000 * match an ignore pattern for the change to be 1001 * ignored. 1002 */ 1003 if (a <= b) { /* Changes and deletes. */ 1004 for (i = a; i <= b; i++) { 1005 line = preadline(fileno(f1), 1006 ixold[i] - ixold[i - 1], ixold[i - 1]); 1007 if (!ignoreline(line, skip_blanks)) 1008 goto proceed; 1009 } 1010 } 1011 if (a > b || c <= d) { /* Changes and inserts. */ 1012 for (i = c; i <= d; i++) { 1013 line = preadline(fileno(f2), 1014 ixnew[i] - ixnew[i - 1], ixnew[i - 1]); 1015 if (!ignoreline(line, skip_blanks)) 1016 goto proceed; 1017 } 1018 } 1019 return; 1020 } 1021 proceed: 1022 if (*pflags & D_HEADER && diff_format != D_BRIEF) { 1023 diff_output("%s %s %s\n", diffargs, file1, file2); 1024 *pflags &= ~D_HEADER; 1025 } 1026 if (diff_format == D_CONTEXT || diff_format == D_UNIFIED) { 1027 /* 1028 * Allocate change records as needed. 1029 */ 1030 if (context_vec_ptr == context_vec_end - 1) { 1031 ptrdiff_t offset = context_vec_ptr - context_vec_start; 1032 max_context <<= 1; 1033 context_vec_start = xreallocarray(context_vec_start, 1034 max_context, sizeof(*context_vec_start)); 1035 context_vec_end = context_vec_start + max_context; 1036 context_vec_ptr = context_vec_start + offset; 1037 } 1038 if (anychange == 0) { 1039 /* 1040 * Print the context/unidiff header first time through. 1041 */ 1042 print_header(file1, file2); 1043 anychange = 1; 1044 } else if (a > context_vec_ptr->b + (2 * diff_context) + 1 && 1045 c > context_vec_ptr->d + (2 * diff_context) + 1) { 1046 /* 1047 * If this change is more than 'diff_context' lines from the 1048 * previous change, dump the record and reset it. 1049 */ 1050 if (diff_format == D_CONTEXT) 1051 dump_context_vec(f1, f2, *pflags); 1052 else 1053 dump_unified_vec(f1, f2, *pflags); 1054 } 1055 context_vec_ptr++; 1056 context_vec_ptr->a = a; 1057 context_vec_ptr->b = b; 1058 context_vec_ptr->c = c; 1059 context_vec_ptr->d = d; 1060 return; 1061 } 1062 if (anychange == 0) 1063 anychange = 1; 1064 switch (diff_format) { 1065 case D_BRIEF: 1066 return; 1067 case D_NORMAL: 1068 case D_EDIT: 1069 range(a, b, ","); 1070 diff_output("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1071 if (diff_format == D_NORMAL) 1072 range(c, d, ","); 1073 diff_output("\n"); 1074 break; 1075 case D_REVERSE: 1076 diff_output("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1077 range(a, b, " "); 1078 diff_output("\n"); 1079 break; 1080 case D_NREVERSE: 1081 if (a > b) 1082 diff_output("a%d %d\n", b, d - c + 1); 1083 else { 1084 diff_output("d%d %d\n", a, b - a + 1); 1085 if (!(c > d)) 1086 /* add changed lines */ 1087 diff_output("a%d %d\n", b, d - c + 1); 1088 } 1089 break; 1090 } 1091 if (diff_format == D_GFORMAT) { 1092 curpos = ftell(f1); 1093 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1094 nc = ixold[a > b ? b : a - 1] - curpos; 1095 for (i = 0; i < nc; i++) 1096 diff_output("%c", getc(f1)); 1097 for (walk = group_format; *walk != '\0'; walk++) { 1098 if (*walk == '%') { 1099 walk++; 1100 switch (*walk) { 1101 case '<': 1102 fetch(ixold, a, b, f1, '<', 1, *pflags); 1103 break; 1104 case '>': 1105 fetch(ixnew, c, d, f2, '>', 0, *pflags); 1106 break; 1107 default: 1108 diff_output("%%%c", *walk); 1109 break; 1110 } 1111 continue; 1112 } 1113 diff_output("%c", *walk); 1114 } 1115 } 1116 if (diff_format == D_NORMAL || diff_format == D_IFDEF) { 1117 fetch(ixold, a, b, f1, '<', 1, *pflags); 1118 if (a <= b && c <= d && diff_format == D_NORMAL) 1119 diff_output("---\n"); 1120 } 1121 f = 0; 1122 if (diff_format != D_GFORMAT) 1123 f = fetch(ixnew, c, d, f2, diff_format == D_NORMAL ? '>' : '\0', 0, *pflags); 1124 if (f != 0 && diff_format == D_EDIT) { 1125 /* 1126 * A non-zero return value for D_EDIT indicates that the 1127 * last line printed was a bare dot (".") that has been 1128 * escaped as ".." to prevent ed(1) from misinterpreting 1129 * it. We have to add a substitute command to change this 1130 * back and restart where we left off. 1131 */ 1132 diff_output(".\n"); 1133 diff_output("%ds/.//\n", a + f - 1); 1134 b = a + f - 1; 1135 a = b + 1; 1136 c += f; 1137 goto restart; 1138 } 1139 if ((diff_format == D_EDIT || diff_format == D_REVERSE) && c <= d) 1140 diff_output(".\n"); 1141 if (inifdef) { 1142 diff_output("#endif /* %s */\n", ifdefname); 1143 inifdef = 0; 1144 } 1145 } 1146 1147 static int 1148 fetch(long *f, int a, int b, FILE *lb, int ch, int oldfile, int flags) 1149 { 1150 int i, j, c, lastc, col, nc; 1151 int newcol; 1152 1153 /* 1154 * When doing #ifdef's, copy down to current line 1155 * if this is the first file, so that stuff makes it to output. 1156 */ 1157 if ((diff_format == D_IFDEF) && oldfile) { 1158 long curpos = ftell(lb); 1159 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1160 nc = f[a > b ? b : a - 1] - curpos; 1161 for (i = 0; i < nc; i++) 1162 diff_output("%c", getc(lb)); 1163 } 1164 if (a > b) 1165 return (0); 1166 if (diff_format == D_IFDEF) { 1167 if (inifdef) { 1168 diff_output("#else /* %s%s */\n", 1169 oldfile == 1 ? "!" : "", ifdefname); 1170 } else { 1171 if (oldfile) 1172 diff_output("#ifndef %s\n", ifdefname); 1173 else 1174 diff_output("#ifdef %s\n", ifdefname); 1175 } 1176 inifdef = 1 + oldfile; 1177 } 1178 for (i = a; i <= b; i++) { 1179 fseek(lb, f[i - 1], SEEK_SET); 1180 nc = f[i] - f[i - 1]; 1181 if ((diff_format != D_IFDEF && diff_format != D_GFORMAT) && 1182 ch != '\0') { 1183 diff_output("%c", ch); 1184 if (Tflag && (diff_format == D_NORMAL || diff_format == D_CONTEXT 1185 || diff_format == D_UNIFIED)) 1186 diff_output("\t"); 1187 else if (diff_format != D_UNIFIED) 1188 diff_output(" "); 1189 } 1190 col = 0; 1191 for (j = 0, lastc = '\0'; j < nc; j++, lastc = c) { 1192 if ((c = getc(lb)) == EOF) { 1193 if (diff_format == D_EDIT || diff_format == D_REVERSE || 1194 diff_format == D_NREVERSE) 1195 warnx("No newline at end of file"); 1196 else 1197 diff_output("\n\\ No newline at end of " 1198 "file\n"); 1199 return (0); 1200 } 1201 if (c == '\t' && (flags & D_EXPANDTABS)) { 1202 newcol = ((col/tabsize)+1)*tabsize; 1203 do { 1204 diff_output(" "); 1205 } while (++col < newcol); 1206 } else { 1207 if (diff_format == D_EDIT && j == 1 && c == '\n' 1208 && lastc == '.') { 1209 /* 1210 * Don't print a bare "." line 1211 * since that will confuse ed(1). 1212 * Print ".." instead and return, 1213 * giving the caller an offset 1214 * from which to restart. 1215 */ 1216 diff_output(".\n"); 1217 return (i - a + 1); 1218 } 1219 diff_output("%c", c); 1220 col++; 1221 } 1222 } 1223 } 1224 return (0); 1225 } 1226 1227 /* 1228 * Hash function taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. 1229 */ 1230 static int 1231 readhash(FILE *f, int flags) 1232 { 1233 int i, t, space; 1234 int sum; 1235 1236 sum = 1; 1237 space = 0; 1238 if ((flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) == 0) { 1239 if (flags & D_IGNORECASE) 1240 for (i = 0; (t = getc(f)) != '\n'; i++) { 1241 if (flags & D_STRIPCR && t == '\r') { 1242 t = getc(f); 1243 if (t == '\n') 1244 break; 1245 ungetc(t, f); 1246 } 1247 if (t == EOF) { 1248 if (i == 0) 1249 return (0); 1250 break; 1251 } 1252 sum = sum * 127 + chrtran(t); 1253 } 1254 else 1255 for (i = 0; (t = getc(f)) != '\n'; i++) { 1256 if (flags & D_STRIPCR && t == '\r') { 1257 t = getc(f); 1258 if (t == '\n') 1259 break; 1260 ungetc(t, f); 1261 } 1262 if (t == EOF) { 1263 if (i == 0) 1264 return (0); 1265 break; 1266 } 1267 sum = sum * 127 + t; 1268 } 1269 } else { 1270 for (i = 0;;) { 1271 switch (t = getc(f)) { 1272 case '\r': 1273 case '\t': 1274 case '\v': 1275 case '\f': 1276 case ' ': 1277 space++; 1278 continue; 1279 default: 1280 if (space && (flags & D_IGNOREBLANKS) == 0) { 1281 i++; 1282 space = 0; 1283 } 1284 sum = sum * 127 + chrtran(t); 1285 i++; 1286 continue; 1287 case EOF: 1288 if (i == 0) 1289 return (0); 1290 /* FALLTHROUGH */ 1291 case '\n': 1292 break; 1293 } 1294 break; 1295 } 1296 } 1297 /* 1298 * There is a remote possibility that we end up with a zero sum. 1299 * Zero is used as an EOF marker, so return 1 instead. 1300 */ 1301 return (sum == 0 ? 1 : sum); 1302 } 1303 1304 static int 1305 asciifile(FILE *f) 1306 { 1307 unsigned char buf[BUFSIZ]; 1308 size_t cnt; 1309 1310 if (f == NULL) 1311 return (1); 1312 1313 rewind(f); 1314 cnt = fread(buf, 1, sizeof(buf), f); 1315 return (memchr(buf, '\0', cnt) == NULL); 1316 } 1317 1318 #define begins_with(s, pre) (strncmp(s, pre, sizeof(pre)-1) == 0) 1319 1320 static char * 1321 match_function(const long *f, int pos, FILE *fp) 1322 { 1323 unsigned char buf[FUNCTION_CONTEXT_SIZE]; 1324 size_t nc; 1325 int last = lastline; 1326 const char *state = NULL; 1327 1328 lastline = pos; 1329 while (pos > last) { 1330 fseek(fp, f[pos - 1], SEEK_SET); 1331 nc = f[pos] - f[pos - 1]; 1332 if (nc >= sizeof(buf)) 1333 nc = sizeof(buf) - 1; 1334 nc = fread(buf, 1, nc, fp); 1335 if (nc > 0) { 1336 buf[nc] = '\0'; 1337 buf[strcspn(buf, "\n")] = '\0'; 1338 if (isalpha(buf[0]) || buf[0] == '_' || buf[0] == '$') { 1339 if (begins_with(buf, "private:")) { 1340 if (!state) 1341 state = " (private)"; 1342 } else if (begins_with(buf, "protected:")) { 1343 if (!state) 1344 state = " (protected)"; 1345 } else if (begins_with(buf, "public:")) { 1346 if (!state) 1347 state = " (public)"; 1348 } else { 1349 strlcpy(lastbuf, buf, sizeof lastbuf); 1350 if (state) 1351 strlcat(lastbuf, state, 1352 sizeof lastbuf); 1353 lastmatchline = pos; 1354 return lastbuf; 1355 } 1356 } 1357 } 1358 pos--; 1359 } 1360 return lastmatchline > 0 ? lastbuf : NULL; 1361 } 1362 1363 /* dump accumulated "context" diff changes */ 1364 static void 1365 dump_context_vec(FILE *f1, FILE *f2, int flags) 1366 { 1367 struct context_vec *cvp = context_vec_start; 1368 int lowa, upb, lowc, upd, do_output; 1369 int a, b, c, d; 1370 char ch, *f; 1371 1372 if (context_vec_start > context_vec_ptr) 1373 return; 1374 1375 b = d = 0; /* gcc */ 1376 lowa = MAX(1, cvp->a - diff_context); 1377 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1378 lowc = MAX(1, cvp->c - diff_context); 1379 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1380 1381 diff_output("***************"); 1382 if ((flags & D_PROTOTYPE)) { 1383 f = match_function(ixold, lowa-1, f1); 1384 if (f != NULL) 1385 diff_output(" %s", f); 1386 } 1387 diff_output("\n*** "); 1388 range(lowa, upb, ","); 1389 diff_output(" ****\n"); 1390 1391 /* 1392 * Output changes to the "old" file. The first loop suppresses 1393 * output if there were no changes to the "old" file (we'll see 1394 * the "old" lines as context in the "new" list). 1395 */ 1396 do_output = 0; 1397 for (; cvp <= context_vec_ptr; cvp++) 1398 if (cvp->a <= cvp->b) { 1399 cvp = context_vec_start; 1400 do_output++; 1401 break; 1402 } 1403 if (do_output) { 1404 while (cvp <= context_vec_ptr) { 1405 a = cvp->a; 1406 b = cvp->b; 1407 c = cvp->c; 1408 d = cvp->d; 1409 1410 if (a <= b && c <= d) 1411 ch = 'c'; 1412 else 1413 ch = (a <= b) ? 'd' : 'a'; 1414 1415 if (ch == 'a') 1416 fetch(ixold, lowa, b, f1, ' ', 0, flags); 1417 else { 1418 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1419 fetch(ixold, a, b, f1, 1420 ch == 'c' ? '!' : '-', 0, flags); 1421 } 1422 lowa = b + 1; 1423 cvp++; 1424 } 1425 fetch(ixold, b + 1, upb, f1, ' ', 0, flags); 1426 } 1427 /* output changes to the "new" file */ 1428 diff_output("--- "); 1429 range(lowc, upd, ","); 1430 diff_output(" ----\n"); 1431 1432 do_output = 0; 1433 for (cvp = context_vec_start; cvp <= context_vec_ptr; cvp++) 1434 if (cvp->c <= cvp->d) { 1435 cvp = context_vec_start; 1436 do_output++; 1437 break; 1438 } 1439 if (do_output) { 1440 while (cvp <= context_vec_ptr) { 1441 a = cvp->a; 1442 b = cvp->b; 1443 c = cvp->c; 1444 d = cvp->d; 1445 1446 if (a <= b && c <= d) 1447 ch = 'c'; 1448 else 1449 ch = (a <= b) ? 'd' : 'a'; 1450 1451 if (ch == 'd') 1452 fetch(ixnew, lowc, d, f2, ' ', 0, flags); 1453 else { 1454 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1455 fetch(ixnew, c, d, f2, 1456 ch == 'c' ? '!' : '+', 0, flags); 1457 } 1458 lowc = d + 1; 1459 cvp++; 1460 } 1461 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1462 } 1463 context_vec_ptr = context_vec_start - 1; 1464 } 1465 1466 /* dump accumulated "unified" diff changes */ 1467 static void 1468 dump_unified_vec(FILE *f1, FILE *f2, int flags) 1469 { 1470 struct context_vec *cvp = context_vec_start; 1471 int lowa, upb, lowc, upd; 1472 int a, b, c, d; 1473 char ch, *f; 1474 1475 if (context_vec_start > context_vec_ptr) 1476 return; 1477 1478 b = d = 0; /* gcc */ 1479 lowa = MAX(1, cvp->a - diff_context); 1480 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1481 lowc = MAX(1, cvp->c - diff_context); 1482 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1483 1484 diff_output("@@ -"); 1485 uni_range(lowa, upb); 1486 diff_output(" +"); 1487 uni_range(lowc, upd); 1488 diff_output(" @@"); 1489 if ((flags & D_PROTOTYPE)) { 1490 f = match_function(ixold, lowa-1, f1); 1491 if (f != NULL) 1492 diff_output(" %s", f); 1493 } 1494 diff_output("\n"); 1495 1496 /* 1497 * Output changes in "unified" diff format--the old and new lines 1498 * are printed together. 1499 */ 1500 for (; cvp <= context_vec_ptr; cvp++) { 1501 a = cvp->a; 1502 b = cvp->b; 1503 c = cvp->c; 1504 d = cvp->d; 1505 1506 /* 1507 * c: both new and old changes 1508 * d: only changes in the old file 1509 * a: only changes in the new file 1510 */ 1511 if (a <= b && c <= d) 1512 ch = 'c'; 1513 else 1514 ch = (a <= b) ? 'd' : 'a'; 1515 1516 switch (ch) { 1517 case 'c': 1518 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1519 fetch(ixold, a, b, f1, '-', 0, flags); 1520 fetch(ixnew, c, d, f2, '+', 0, flags); 1521 break; 1522 case 'd': 1523 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1524 fetch(ixold, a, b, f1, '-', 0, flags); 1525 break; 1526 case 'a': 1527 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1528 fetch(ixnew, c, d, f2, '+', 0, flags); 1529 break; 1530 } 1531 lowa = b + 1; 1532 lowc = d + 1; 1533 } 1534 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1535 1536 context_vec_ptr = context_vec_start - 1; 1537 } 1538 1539 static void 1540 print_header(const char *file1, const char *file2) 1541 { 1542 const char *time_format; 1543 char buf1[256]; 1544 char buf2[256]; 1545 char end1[10]; 1546 char end2[10]; 1547 struct tm tm1, tm2, *tm_ptr1, *tm_ptr2; 1548 int nsec1 = stb1.st_mtim.tv_nsec; 1549 int nsec2 = stb2.st_mtim.tv_nsec; 1550 1551 time_format = "%Y-%m-%d %H:%M:%S"; 1552 1553 if (cflag) 1554 time_format = "%c"; 1555 tm_ptr1 = localtime_r(&stb1.st_mtime, &tm1); 1556 tm_ptr2 = localtime_r(&stb2.st_mtime, &tm2); 1557 strftime(buf1, 256, time_format, tm_ptr1); 1558 strftime(buf2, 256, time_format, tm_ptr2); 1559 if (!cflag) { 1560 strftime(end1, 10, "%z", tm_ptr1); 1561 strftime(end2, 10, "%z", tm_ptr2); 1562 sprintf(buf1, "%s.%.9d %s", buf1, nsec1, end1); 1563 sprintf(buf2, "%s.%.9d %s", buf2, nsec2, end2); 1564 } 1565 if (label[0] != NULL) 1566 diff_output("%s %s\n", diff_format == D_CONTEXT ? "***" : "---", 1567 label[0]); 1568 else 1569 diff_output("%s %s\t%s\n", diff_format == D_CONTEXT ? "***" : "---", 1570 file1, buf1); 1571 if (label[1] != NULL) 1572 diff_output("%s %s\n", diff_format == D_CONTEXT ? "---" : "+++", 1573 label[1]); 1574 else 1575 diff_output("%s %s\t%s\n", diff_format == D_CONTEXT ? "---" : "+++", 1576 file2, buf2); 1577 } 1578