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