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