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