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 67#include <sys/capsicum.h> 68#include <sys/stat.h> 69 70#include <capsicum_helpers.h> 71#include <ctype.h> 72#include <err.h> 73#include <errno.h> 74#include <fcntl.h> 75#include <limits.h> 76#include <math.h> 77#include <paths.h> 78#include <regex.h> 79#include <stdbool.h> 80#include <stddef.h> 81#include <stdint.h> 82#include <stdio.h> 83#include <stdlib.h> 84#include <string.h> 85 86#include "pr.h" 87#include "diff.h" 88#include "xmalloc.h" 89 90/* 91 * diff - compare two files. 92 */ 93 94/* 95 * Uses an algorithm due to Harold Stone, which finds a pair of longest 96 * identical subsequences in the two files. 97 * 98 * The major goal is to generate the match vector J. J[i] is the index of 99 * the line in file1 corresponding to line i file0. J[i] = 0 if there is no 100 * such line in file1. 101 * 102 * Lines are hashed so as to work in core. All potential matches are 103 * located by sorting the lines of each file on the hash (called 104 * ``value''). In particular, this collects the equivalence classes in 105 * file1 together. Subroutine equiv replaces the value of each line in 106 * file0 by the index of the first element of its matching equivalence in 107 * (the reordered) file1. To save space equiv squeezes file1 into a single 108 * array member in which the equivalence classes are simply concatenated, 109 * except that their first members are flagged by changing sign. 110 * 111 * Next the indices that point into member are unsorted into array class 112 * according to the original order of file0. 113 * 114 * The cleverness lies in routine stone. This marches through the lines of 115 * file0, developing a vector klist of "k-candidates". At step i 116 * a k-candidate is a matched pair of lines x,y (x in file0 y in file1) 117 * such that there is a common subsequence of length k between the first 118 * i lines of file0 and the first y lines of file1, but there is no such 119 * subsequence for any smaller y. x is the earliest possible mate to y that 120 * occurs in such a subsequence. 121 * 122 * Whenever any of the members of the equivalence class of lines in file1 123 * matable to a line in file0 has serial number less than the y of some 124 * k-candidate, that k-candidate with the smallest such y is replaced. The 125 * new k-candidate is chained (via pred) to the current k-1 candidate so 126 * that the actual subsequence can be recovered. When a member has serial 127 * number greater that the y of all k-candidates, the klist is extended. At 128 * the end, the longest subsequence is pulled out and placed in the array J 129 * by unravel. 130 * 131 * With J in hand, the matches there recorded are check'ed against reality 132 * to assure that no spurious matches have crept in due to hashing. If they 133 * have, they are broken, and "jackpot" is recorded -- a harmless matter 134 * except that a true match for a spuriously mated line may now be 135 * unnecessarily reported as a change. 136 * 137 * Much of the complexity of the program comes simply from trying to 138 * minimize core utilization and maximize the range of doable problems by 139 * dynamically allocating what is needed and reusing what is not. The core 140 * requirements for problems larger than somewhat are (in words) 141 * 2*length(file0) + length(file1) + 3*(number of k-candidates installed), 142 * typically about 6n words for files of length n. 143 */ 144 145struct cand { 146 int x; 147 int y; 148 int pred; 149}; 150 151static struct line { 152 int serial; 153 int value; 154} *file[2]; 155 156/* 157 * The following struct is used to record change information when 158 * doing a "context" or "unified" diff. (see routine "change" to 159 * understand the highly mnemonic field names) 160 */ 161struct context_vec { 162 int a; /* start line in old file */ 163 int b; /* end line in old file */ 164 int c; /* start line in new file */ 165 int d; /* end line in new file */ 166}; 167 168enum readhash { RH_BINARY, RH_OK, RH_EOF }; 169 170static int diffreg_stone(char *, char *, int, int); 171static FILE *opentemp(const char *); 172static void output(char *, FILE *, char *, FILE *, int); 173static void check(FILE *, FILE *, int); 174static void range(int, int, const char *); 175static void uni_range(int, int); 176static void dump_context_vec(FILE *, FILE *, int); 177static void dump_unified_vec(FILE *, FILE *, int); 178static bool prepare(int, FILE *, size_t, int); 179static void prune(void); 180static void equiv(struct line *, int, struct line *, int, int *); 181static void unravel(int); 182static void unsort(struct line *, int, int *); 183static void change(char *, FILE *, char *, FILE *, int, int, int, int, int *); 184static void sort(struct line *, int); 185static void print_header(const char *, const char *); 186static void print_space(int, int, int); 187static bool ignoreline_pattern(char *); 188static bool ignoreline(char *, bool); 189static int asciifile(FILE *); 190static int fetch(long *, int, int, FILE *, int, int, int); 191static int newcand(int, int, int); 192static int search(int *, int, int); 193static int skipline(FILE *); 194static int stone(int *, int, int *, int *, int); 195static enum readhash readhash(FILE *, int, unsigned *); 196static int files_differ(FILE *, FILE *, int); 197static char *match_function(const long *, int, FILE *); 198static char *preadline(int, size_t, off_t); 199 200static int *J; /* will be overlaid on class */ 201static int *class; /* will be overlaid on file[0] */ 202static int *klist; /* will be overlaid on file[0] after class */ 203static int *member; /* will be overlaid on file[1] */ 204static int clen; 205static int inifdef; /* whether or not we are in a #ifdef block */ 206static int len[2]; 207static int pref, suff; /* length of prefix and suffix */ 208static int slen[2]; 209static int anychange; 210static int hw, lpad,rpad; /* half width and padding */ 211static int edoffset; 212static long *ixnew; /* will be overlaid on file[1] */ 213static long *ixold; /* will be overlaid on klist */ 214static struct cand *clist; /* merely a free storage pot for candidates */ 215static int clistlen; /* the length of clist */ 216static struct line *sfile[2]; /* shortened by pruning common prefix/suffix */ 217static int (*chrtran)(int); /* translation table for case-folding */ 218static struct context_vec *context_vec_start; 219static struct context_vec *context_vec_end; 220static struct context_vec *context_vec_ptr; 221 222#define FUNCTION_CONTEXT_SIZE 55 223static char lastbuf[FUNCTION_CONTEXT_SIZE]; 224static int lastline; 225static int lastmatchline; 226 227int 228diffreg(char *file1, char *file2, int flags, int capsicum) 229{ 230 /* 231 * If we have set the algorithm with -A or --algorithm use that if we 232 * can and if not print an error. 233 */ 234 if (diff_algorithm_set) { 235 if (diff_algorithm == D_DIFFMYERS || 236 diff_algorithm == D_DIFFPATIENCE) { 237 if (can_libdiff(flags)) 238 return diffreg_new(file1, file2, flags, capsicum); 239 else 240 errx(2, "cannot use Myers algorithm with selected options"); 241 } else { 242 /* Fallback to using stone. */ 243 return diffreg_stone(file1, file2, flags, capsicum); 244 } 245 } else { 246 if (can_libdiff(flags)) 247 return diffreg_new(file1, file2, flags, capsicum); 248 else 249 return diffreg_stone(file1, file2, flags, capsicum); 250 } 251} 252 253static int 254clow2low(int c) 255{ 256 257 return (c); 258} 259 260static int 261cup2low(int c) 262{ 263 264 return (tolower(c)); 265} 266 267int 268diffreg_stone(char *file1, char *file2, int flags, int capsicum) 269{ 270 FILE *f1, *f2; 271 int i, rval; 272 struct pr *pr = NULL; 273 cap_rights_t rights_ro; 274 275 f1 = f2 = NULL; 276 rval = D_SAME; 277 anychange = 0; 278 lastline = 0; 279 lastmatchline = 0; 280 281 /* 282 * In side-by-side mode, we need to print the left column, a 283 * change marker surrounded by padding, and the right column. 284 * 285 * If expanding tabs, we don't care about alignment, so we simply 286 * subtract 3 from the width and divide by two. 287 * 288 * If not expanding tabs, we need to ensure that the right column 289 * is aligned to a tab stop. We start with the same formula, then 290 * decrement until we reach a size that lets us tab-align the 291 * right column. We then adjust the width down if necessary for 292 * the padding calculation to work. 293 * 294 * Left padding is half the space left over, rounded down; right 295 * padding is whatever is needed to match the width. 296 */ 297 if (diff_format == D_SIDEBYSIDE) { 298 if (flags & D_EXPANDTABS) { 299 if (width > 3) { 300 hw = (width - 3) / 2; 301 } else { 302 /* not enough space */ 303 hw = 0; 304 } 305 } else if (width <= 3 || width <= tabsize) { 306 /* not enough space */ 307 hw = 0; 308 } else { 309 hw = (width - 3) / 2; 310 while (hw > 0 && roundup(hw + 3, tabsize) + hw > width) 311 hw--; 312 if (width - (roundup(hw + 3, tabsize) + hw) < tabsize) 313 width = roundup(hw + 3, tabsize) + hw; 314 } 315 lpad = (width - hw * 2 - 1) / 2; 316 rpad = (width - hw * 2 - 1) - lpad; 317 } 318 319 if (flags & D_IGNORECASE) 320 chrtran = cup2low; 321 else 322 chrtran = clow2low; 323 if (S_ISDIR(stb1.st_mode) != S_ISDIR(stb2.st_mode)) 324 return (S_ISDIR(stb1.st_mode) ? D_MISMATCH1 : D_MISMATCH2); 325 if (strcmp(file1, "-") == 0 && strcmp(file2, "-") == 0) 326 goto closem; 327 328 if (flags & D_EMPTY1) 329 f1 = fopen(_PATH_DEVNULL, "r"); 330 else { 331 if (!S_ISREG(stb1.st_mode)) { 332 if ((f1 = opentemp(file1)) == NULL || 333 fstat(fileno(f1), &stb1) == -1) { 334 warn("%s", file1); 335 rval = D_ERROR; 336 status |= 2; 337 goto closem; 338 } 339 } else if (strcmp(file1, "-") == 0) 340 f1 = stdin; 341 else 342 f1 = fopen(file1, "r"); 343 } 344 if (f1 == NULL) { 345 warn("%s", file1); 346 rval = D_ERROR; 347 status |= 2; 348 goto closem; 349 } 350 351 if (flags & D_EMPTY2) 352 f2 = fopen(_PATH_DEVNULL, "r"); 353 else { 354 if (!S_ISREG(stb2.st_mode)) { 355 if ((f2 = opentemp(file2)) == NULL || 356 fstat(fileno(f2), &stb2) == -1) { 357 warn("%s", file2); 358 rval = D_ERROR; 359 status |= 2; 360 goto closem; 361 } 362 } else if (strcmp(file2, "-") == 0) 363 f2 = stdin; 364 else 365 f2 = fopen(file2, "r"); 366 } 367 if (f2 == NULL) { 368 warn("%s", file2); 369 rval = D_ERROR; 370 status |= 2; 371 goto closem; 372 } 373 374 if (lflag) 375 pr = start_pr(file1, file2); 376 377 if (capsicum) { 378 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); 379 if (caph_rights_limit(fileno(f1), &rights_ro) < 0) 380 err(2, "unable to limit rights on: %s", file1); 381 if (caph_rights_limit(fileno(f2), &rights_ro) < 0) 382 err(2, "unable to limit rights on: %s", file2); 383 if (fileno(f1) == STDIN_FILENO || fileno(f2) == STDIN_FILENO) { 384 /* stdin has already been limited */ 385 if (caph_limit_stderr() == -1) 386 err(2, "unable to limit stderr"); 387 if (caph_limit_stdout() == -1) 388 err(2, "unable to limit stdout"); 389 } else if (caph_limit_stdio() == -1) 390 err(2, "unable to limit stdio"); 391 392 caph_cache_catpages(); 393 caph_cache_tzdata(); 394 if (caph_enter() < 0) 395 err(2, "unable to enter capability mode"); 396 } 397 398 switch (files_differ(f1, f2, flags)) { 399 case 0: 400 goto closem; 401 case 1: 402 break; 403 default: 404 /* error */ 405 rval = D_ERROR; 406 status |= 2; 407 goto closem; 408 } 409 410 if (diff_format == D_BRIEF && ignore_pats == NULL && 411 (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE| 412 D_SKIPBLANKLINES|D_STRIPCR)) == 0) 413 { 414 rval = D_DIFFER; 415 status |= 1; 416 goto closem; 417 } 418 if ((flags & D_FORCEASCII) != 0) { 419 (void)prepare(0, f1, stb1.st_size, flags); 420 (void)prepare(1, f2, stb2.st_size, flags); 421 } else if (!asciifile(f1) || !asciifile(f2) || 422 !prepare(0, f1, stb1.st_size, flags) || 423 !prepare(1, f2, stb2.st_size, flags)) { 424 rval = D_BINARY; 425 status |= 1; 426 goto closem; 427 } 428 429 prune(); 430 sort(sfile[0], slen[0]); 431 sort(sfile[1], slen[1]); 432 433 member = (int *)file[1]; 434 equiv(sfile[0], slen[0], sfile[1], slen[1], member); 435 member = xreallocarray(member, slen[1] + 2, sizeof(*member)); 436 437 class = (int *)file[0]; 438 unsort(sfile[0], slen[0], class); 439 class = xreallocarray(class, slen[0] + 2, sizeof(*class)); 440 441 klist = xcalloc(slen[0] + 2, sizeof(*klist)); 442 clen = 0; 443 clistlen = 100; 444 clist = xcalloc(clistlen, sizeof(*clist)); 445 i = stone(class, slen[0], member, klist, flags); 446 free(member); 447 free(class); 448 449 J = xreallocarray(J, len[0] + 2, sizeof(*J)); 450 unravel(klist[i]); 451 free(clist); 452 free(klist); 453 454 ixold = xreallocarray(ixold, len[0] + 2, sizeof(*ixold)); 455 ixnew = xreallocarray(ixnew, len[1] + 2, sizeof(*ixnew)); 456 check(f1, f2, flags); 457 output(file1, f1, file2, f2, flags); 458 459closem: 460 if (pr != NULL) 461 stop_pr(pr); 462 if (anychange) { 463 status |= 1; 464 if (rval == D_SAME) 465 rval = D_DIFFER; 466 } 467 if (f1 != NULL) 468 fclose(f1); 469 if (f2 != NULL) 470 fclose(f2); 471 472 return (rval); 473} 474 475/* 476 * Check to see if the given files differ. 477 * Returns 0 if they are the same, 1 if different, and -1 on error. 478 * XXX - could use code from cmp(1) [faster] 479 */ 480static int 481files_differ(FILE *f1, FILE *f2, int flags) 482{ 483 char buf1[BUFSIZ], buf2[BUFSIZ]; 484 size_t i, j; 485 486 if ((flags & (D_EMPTY1|D_EMPTY2)) || stb1.st_size != stb2.st_size || 487 (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)) 488 return (1); 489 490 if (stb1.st_dev == stb2.st_dev && stb1.st_ino == stb2.st_ino) 491 return (0); 492 493 for (;;) { 494 i = fread(buf1, 1, sizeof(buf1), f1); 495 j = fread(buf2, 1, sizeof(buf2), f2); 496 if ((!i && ferror(f1)) || (!j && ferror(f2))) 497 return (-1); 498 if (i != j) 499 return (1); 500 if (i == 0) 501 return (0); 502 if (memcmp(buf1, buf2, i) != 0) 503 return (1); 504 } 505} 506 507static FILE * 508opentemp(const char *f) 509{ 510 char buf[BUFSIZ], tempfile[PATH_MAX]; 511 ssize_t nread; 512 int ifd, ofd; 513 514 if (strcmp(f, "-") == 0) 515 ifd = STDIN_FILENO; 516 else if ((ifd = open(f, O_RDONLY, 0644)) == -1) 517 return (NULL); 518 519 (void)strlcpy(tempfile, _PATH_TMP "/diff.XXXXXXXX", sizeof(tempfile)); 520 521 if ((ofd = mkstemp(tempfile)) == -1) { 522 close(ifd); 523 return (NULL); 524 } 525 unlink(tempfile); 526 while ((nread = read(ifd, buf, BUFSIZ)) > 0) { 527 if (write(ofd, buf, nread) != nread) { 528 close(ifd); 529 close(ofd); 530 return (NULL); 531 } 532 } 533 close(ifd); 534 lseek(ofd, (off_t)0, SEEK_SET); 535 return (fdopen(ofd, "r")); 536} 537 538static bool 539prepare(int i, FILE *fd, size_t filesize, int flags) 540{ 541 struct line *p; 542 unsigned h; 543 size_t sz, j = 0; 544 enum readhash r; 545 546 rewind(fd); 547 548 sz = MIN(filesize, SIZE_MAX) / 25; 549 if (sz < 100) 550 sz = 100; 551 552 p = xcalloc(sz + 3, sizeof(*p)); 553 while ((r = readhash(fd, flags, &h)) != RH_EOF) 554 switch (r) { 555 case RH_EOF: /* otherwise clang complains */ 556 case RH_BINARY: 557 return (false); 558 case RH_OK: 559 if (j == sz) { 560 sz = sz * 3 / 2; 561 p = xreallocarray(p, sz + 3, sizeof(*p)); 562 } 563 p[++j].value = h; 564 } 565 566 len[i] = j; 567 file[i] = p; 568 569 return (true); 570} 571 572static void 573prune(void) 574{ 575 int i, j; 576 577 for (pref = 0; pref < len[0] && pref < len[1] && 578 file[0][pref + 1].value == file[1][pref + 1].value; 579 pref++) 580 ; 581 for (suff = 0; suff < len[0] - pref && suff < len[1] - pref && 582 file[0][len[0] - suff].value == file[1][len[1] - suff].value; 583 suff++) 584 ; 585 for (j = 0; j < 2; j++) { 586 sfile[j] = file[j] + pref; 587 slen[j] = len[j] - pref - suff; 588 for (i = 0; i <= slen[j]; i++) 589 sfile[j][i].serial = i; 590 } 591} 592 593static void 594equiv(struct line *a, int n, struct line *b, int m, int *c) 595{ 596 int i, j; 597 598 i = j = 1; 599 while (i <= n && j <= m) { 600 if (a[i].value < b[j].value) 601 a[i++].value = 0; 602 else if (a[i].value == b[j].value) 603 a[i++].value = j; 604 else 605 j++; 606 } 607 while (i <= n) 608 a[i++].value = 0; 609 b[m + 1].value = 0; 610 j = 0; 611 while (++j <= m) { 612 c[j] = -b[j].serial; 613 while (b[j + 1].value == b[j].value) { 614 j++; 615 c[j] = b[j].serial; 616 } 617 } 618 c[j] = -1; 619} 620 621static int 622stone(int *a, int n, int *b, int *c, int flags) 623{ 624 int i, k, y, j, l; 625 int oldc, tc, oldl, sq; 626 unsigned numtries, bound; 627 628 if (flags & D_MINIMAL) 629 bound = UINT_MAX; 630 else { 631 sq = sqrt(n); 632 bound = MAX(256, sq); 633 } 634 635 k = 0; 636 c[0] = newcand(0, 0, 0); 637 for (i = 1; i <= n; i++) { 638 j = a[i]; 639 if (j == 0) 640 continue; 641 y = -b[j]; 642 oldl = 0; 643 oldc = c[0]; 644 numtries = 0; 645 do { 646 if (y <= clist[oldc].y) 647 continue; 648 l = search(c, k, y); 649 if (l != oldl + 1) 650 oldc = c[l - 1]; 651 if (l <= k) { 652 if (clist[c[l]].y <= y) 653 continue; 654 tc = c[l]; 655 c[l] = newcand(i, y, oldc); 656 oldc = tc; 657 oldl = l; 658 numtries++; 659 } else { 660 c[l] = newcand(i, y, oldc); 661 k++; 662 break; 663 } 664 } while ((y = b[++j]) > 0 && numtries < bound); 665 } 666 return (k); 667} 668 669static int 670newcand(int x, int y, int pred) 671{ 672 struct cand *q; 673 674 if (clen == clistlen) { 675 clistlen = clistlen * 11 / 10; 676 clist = xreallocarray(clist, clistlen, sizeof(*clist)); 677 } 678 q = clist + clen; 679 q->x = x; 680 q->y = y; 681 q->pred = pred; 682 return (clen++); 683} 684 685static int 686search(int *c, int k, int y) 687{ 688 int i, j, l, t; 689 690 if (clist[c[k]].y < y) /* quick look for typical case */ 691 return (k + 1); 692 i = 0; 693 j = k + 1; 694 for (;;) { 695 l = (i + j) / 2; 696 if (l <= i) 697 break; 698 t = clist[c[l]].y; 699 if (t > y) 700 j = l; 701 else if (t < y) 702 i = l; 703 else 704 return (l); 705 } 706 return (l + 1); 707} 708 709static void 710unravel(int p) 711{ 712 struct cand *q; 713 int i; 714 715 for (i = 0; i <= len[0]; i++) 716 J[i] = i <= pref ? i : 717 i > len[0] - suff ? i + len[1] - len[0] : 0; 718 for (q = clist + p; q->y != 0; q = clist + q->pred) 719 J[q->x + pref] = q->y + pref; 720} 721 722/* 723 * Check does double duty: 724 * 1. ferret out any fortuitous correspondences due to confounding by 725 * hashing (which result in "jackpot") 726 * 2. collect random access indexes to the two files 727 */ 728static void 729check(FILE *f1, FILE *f2, int flags) 730{ 731 int i, j, /* jackpot, */ c, d; 732 long ctold, ctnew; 733 734 rewind(f1); 735 rewind(f2); 736 j = 1; 737 ixold[0] = ixnew[0] = 0; 738 /* jackpot = 0; */ 739 ctold = ctnew = 0; 740 for (i = 1; i <= len[0]; i++) { 741 if (J[i] == 0) { 742 ixold[i] = ctold += skipline(f1); 743 continue; 744 } 745 while (j < J[i]) { 746 ixnew[j] = ctnew += skipline(f2); 747 j++; 748 } 749 if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS | D_IGNORECASE | D_STRIPCR)) { 750 for (;;) { 751 c = getc(f1); 752 d = getc(f2); 753 /* 754 * GNU diff ignores a missing newline 755 * in one file for -b or -w. 756 */ 757 if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS)) { 758 if (c == EOF && isspace(d)) { 759 ctnew++; 760 break; 761 } else if (isspace(c) && d == EOF) { 762 ctold++; 763 break; 764 } 765 } 766 ctold++; 767 ctnew++; 768 if (flags & D_STRIPCR && (c == '\r' || d == '\r')) { 769 if (c == '\r') { 770 if ((c = getc(f1)) == '\n') { 771 ctold++; 772 } else { 773 ungetc(c, f1); 774 } 775 } 776 if (d == '\r') { 777 if ((d = getc(f2)) == '\n') { 778 ctnew++; 779 } else { 780 ungetc(d, f2); 781 } 782 } 783 break; 784 } 785 if ((flags & D_FOLDBLANKS) && isspace(c) && 786 isspace(d)) { 787 do { 788 if (c == '\n') 789 break; 790 ctold++; 791 } while (isspace(c = getc(f1))); 792 do { 793 if (d == '\n') 794 break; 795 ctnew++; 796 } while (isspace(d = getc(f2))); 797 } else if (flags & D_IGNOREBLANKS) { 798 while (isspace(c) && c != '\n') { 799 c = getc(f1); 800 ctold++; 801 } 802 while (isspace(d) && d != '\n') { 803 d = getc(f2); 804 ctnew++; 805 } 806 } 807 if (chrtran(c) != chrtran(d)) { 808 /* jackpot++; */ 809 J[i] = 0; 810 if (c != '\n' && c != EOF) 811 ctold += skipline(f1); 812 if (d != '\n' && c != EOF) 813 ctnew += skipline(f2); 814 break; 815 } 816 if (c == '\n' || c == EOF) 817 break; 818 } 819 } else { 820 for (;;) { 821 ctold++; 822 ctnew++; 823 if ((c = getc(f1)) != (d = getc(f2))) { 824 /* jackpot++; */ 825 J[i] = 0; 826 if (c != '\n' && c != EOF) 827 ctold += skipline(f1); 828 if (d != '\n' && c != EOF) 829 ctnew += skipline(f2); 830 break; 831 } 832 if (c == '\n' || c == EOF) 833 break; 834 } 835 } 836 ixold[i] = ctold; 837 ixnew[j] = ctnew; 838 j++; 839 } 840 for (; j <= len[1]; j++) { 841 ixnew[j] = ctnew += skipline(f2); 842 } 843 /* 844 * if (jackpot) 845 * fprintf(stderr, "jackpot\n"); 846 */ 847} 848 849/* shellsort CACM #201 */ 850static void 851sort(struct line *a, int n) 852{ 853 struct line *ai, *aim, w; 854 int j, m = 0, k; 855 856 if (n == 0) 857 return; 858 for (j = 1; j <= n; j *= 2) 859 m = 2 * j - 1; 860 for (m /= 2; m != 0; m /= 2) { 861 k = n - m; 862 for (j = 1; j <= k; j++) { 863 for (ai = &a[j]; ai > a; ai -= m) { 864 aim = &ai[m]; 865 if (aim < ai) 866 break; /* wraparound */ 867 if (aim->value > ai[0].value || 868 (aim->value == ai[0].value && 869 aim->serial > ai[0].serial)) 870 break; 871 w.value = ai[0].value; 872 ai[0].value = aim->value; 873 aim->value = w.value; 874 w.serial = ai[0].serial; 875 ai[0].serial = aim->serial; 876 aim->serial = w.serial; 877 } 878 } 879 } 880} 881 882static void 883unsort(struct line *f, int l, int *b) 884{ 885 int *a, i; 886 887 a = xcalloc(l + 1, sizeof(*a)); 888 for (i = 1; i <= l; i++) 889 a[f[i].serial] = f[i].value; 890 for (i = 1; i <= l; i++) 891 b[i] = a[i]; 892 free(a); 893} 894 895static int 896skipline(FILE *f) 897{ 898 int i, c; 899 900 for (i = 1; (c = getc(f)) != '\n' && c != EOF; i++) 901 continue; 902 return (i); 903} 904 905static void 906output(char *file1, FILE *f1, char *file2, FILE *f2, int flags) 907{ 908 int i, j, m, i0, i1, j0, j1, nc; 909 910 rewind(f1); 911 rewind(f2); 912 m = len[0]; 913 J[0] = 0; 914 J[m + 1] = len[1] + 1; 915 if (diff_format != D_EDIT) { 916 for (i0 = 1; i0 <= m; i0 = i1 + 1) { 917 while (i0 <= m && J[i0] == J[i0 - 1] + 1) { 918 if (diff_format == D_SIDEBYSIDE && suppress_common != 1) { 919 nc = fetch(ixold, i0, i0, f1, '\0', 1, flags); 920 print_space(nc, hw - nc + lpad + 1 + rpad, flags); 921 fetch(ixnew, J[i0], J[i0], f2, '\0', 0, flags); 922 printf("\n"); 923 } 924 i0++; 925 } 926 j0 = J[i0 - 1] + 1; 927 i1 = i0 - 1; 928 while (i1 < m && J[i1 + 1] == 0) 929 i1++; 930 j1 = J[i1 + 1] - 1; 931 J[i1] = j1; 932 933 /* 934 * When using side-by-side, lines from both of the files are 935 * printed. The algorithm used by diff(1) identifies the ranges 936 * in which two files differ. 937 * See the change() function below. 938 * The for loop below consumes the shorter range, whereas one of 939 * the while loops deals with the longer one. 940 */ 941 if (diff_format == D_SIDEBYSIDE) { 942 for (i = i0, j = j0; i <= i1 && j <= j1; i++, j++) 943 change(file1, f1, file2, f2, i, i, j, j, &flags); 944 945 while (i <= i1) { 946 change(file1, f1, file2, f2, i, i, j + 1, j, &flags); 947 i++; 948 } 949 950 while (j <= j1) { 951 change(file1, f1, file2, f2, i + 1, i, j, j, &flags); 952 j++; 953 } 954 } else 955 change(file1, f1, file2, f2, i0, i1, j0, j1, &flags); 956 } 957 } else { 958 for (i0 = m; i0 >= 1; i0 = i1 - 1) { 959 while (i0 >= 1 && J[i0] == J[i0 + 1] - 1 && J[i0] != 0) 960 i0--; 961 j0 = J[i0 + 1] - 1; 962 i1 = i0 + 1; 963 while (i1 > 1 && J[i1 - 1] == 0) 964 i1--; 965 j1 = J[i1 - 1] + 1; 966 J[i1] = j1; 967 change(file1, f1, file2, f2, i1, i0, j1, j0, &flags); 968 } 969 } 970 if (m == 0) 971 change(file1, f1, file2, f2, 1, 0, 1, len[1], &flags); 972 if (diff_format == D_IFDEF || diff_format == D_GFORMAT) { 973 for (;;) { 974#define c i0 975 if ((c = getc(f1)) == EOF) 976 return; 977 printf("%c", c); 978 } 979#undef c 980 } 981 if (anychange != 0) { 982 if (diff_format == D_CONTEXT) 983 dump_context_vec(f1, f2, flags); 984 else if (diff_format == D_UNIFIED) 985 dump_unified_vec(f1, f2, flags); 986 } 987} 988 989static void 990range(int a, int b, const char *separator) 991{ 992 printf("%d", a > b ? b : a); 993 if (a < b) 994 printf("%s%d", separator, b); 995} 996 997static void 998uni_range(int a, int b) 999{ 1000 if (a < b) 1001 printf("%d,%d", a, b - a + 1); 1002 else if (a == b) 1003 printf("%d", b); 1004 else 1005 printf("%d,0", b); 1006} 1007 1008static char * 1009preadline(int fd, size_t rlen, off_t off) 1010{ 1011 char *line; 1012 ssize_t nr; 1013 1014 line = xmalloc(rlen + 1); 1015 if ((nr = pread(fd, line, rlen, off)) == -1) 1016 err(2, "preadline"); 1017 if (nr > 0 && line[nr-1] == '\n') 1018 nr--; 1019 line[nr] = '\0'; 1020 return (line); 1021} 1022 1023static bool 1024ignoreline_pattern(char *line) 1025{ 1026 int ret; 1027 1028 ret = regexec(&ignore_re, line, 0, NULL, 0); 1029 return (ret == 0); /* if it matched, it should be ignored. */ 1030} 1031 1032static bool 1033ignoreline(char *line, bool skip_blanks) 1034{ 1035 1036 if (skip_blanks && *line == '\0') 1037 return (true); 1038 if (ignore_pats != NULL && ignoreline_pattern(line)) 1039 return (true); 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 */ 1050static void 1051change(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, ignore; 1059 1060 skip_blanks = (*pflags & D_SKIPBLANKLINES); 1061restart: 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 match an ignore 1069 * pattern for the change to be 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 ignore = ignoreline(line, skip_blanks); 1076 free(line); 1077 if (!ignore) 1078 goto proceed; 1079 } 1080 } 1081 if (a > b || c <= d) { /* Changes and inserts. */ 1082 for (i = c; i <= d; i++) { 1083 line = preadline(fileno(f2), 1084 ixnew[i] - ixnew[i - 1], ixnew[i - 1]); 1085 ignore = ignoreline(line, skip_blanks); 1086 free(line); 1087 if (!ignore) 1088 goto proceed; 1089 } 1090 } 1091 return; 1092 } 1093proceed: 1094 if (*pflags & D_HEADER && diff_format != D_BRIEF) { 1095 printf("%s %s %s\n", diffargs, file1, file2); 1096 *pflags &= ~D_HEADER; 1097 } 1098 if (diff_format == D_CONTEXT || diff_format == D_UNIFIED) { 1099 /* 1100 * Allocate change records as needed. 1101 */ 1102 if (context_vec_start == NULL || 1103 context_vec_ptr == context_vec_end - 1) { 1104 ptrdiff_t offset = -1; 1105 1106 if (context_vec_start != NULL) 1107 offset = context_vec_ptr - context_vec_start; 1108 max_context <<= 1; 1109 context_vec_start = xreallocarray(context_vec_start, 1110 max_context, sizeof(*context_vec_start)); 1111 context_vec_end = context_vec_start + max_context; 1112 context_vec_ptr = context_vec_start + offset; 1113 } 1114 if (anychange == 0) { 1115 /* 1116 * Print the context/unidiff header first time through. 1117 */ 1118 print_header(file1, file2); 1119 anychange = 1; 1120 } else if (a > context_vec_ptr->b + (2 * diff_context) + 1 && 1121 c > context_vec_ptr->d + (2 * diff_context) + 1) { 1122 /* 1123 * If this change is more than 'diff_context' lines from the 1124 * previous change, dump the record and reset it. 1125 */ 1126 if (diff_format == D_CONTEXT) 1127 dump_context_vec(f1, f2, *pflags); 1128 else 1129 dump_unified_vec(f1, f2, *pflags); 1130 } 1131 context_vec_ptr++; 1132 context_vec_ptr->a = a; 1133 context_vec_ptr->b = b; 1134 context_vec_ptr->c = c; 1135 context_vec_ptr->d = d; 1136 return; 1137 } 1138 if (anychange == 0) 1139 anychange = 1; 1140 switch (diff_format) { 1141 case D_BRIEF: 1142 return; 1143 case D_NORMAL: 1144 case D_EDIT: 1145 range(a, b, ","); 1146 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1147 if (diff_format == D_NORMAL) 1148 range(c, d, ","); 1149 printf("\n"); 1150 break; 1151 case D_REVERSE: 1152 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1153 range(a, b, " "); 1154 printf("\n"); 1155 break; 1156 case D_NREVERSE: 1157 if (a > b) 1158 printf("a%d %d\n", b, d - c + 1); 1159 else { 1160 printf("d%d %d\n", a, b - a + 1); 1161 if (!(c > d)) 1162 /* add changed lines */ 1163 printf("a%d %d\n", b, d - c + 1); 1164 } 1165 break; 1166 } 1167 if (diff_format == D_GFORMAT) { 1168 curpos = ftell(f1); 1169 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1170 nc = ixold[a > b ? b : a - 1] - curpos; 1171 for (i = 0; i < nc; i++) 1172 printf("%c", getc(f1)); 1173 for (walk = group_format; *walk != '\0'; walk++) { 1174 if (*walk == '%') { 1175 walk++; 1176 switch (*walk) { 1177 case '<': 1178 fetch(ixold, a, b, f1, '<', 1, *pflags); 1179 break; 1180 case '>': 1181 fetch(ixnew, c, d, f2, '>', 0, *pflags); 1182 break; 1183 default: 1184 printf("%%%c", *walk); 1185 break; 1186 } 1187 continue; 1188 } 1189 printf("%c", *walk); 1190 } 1191 } 1192 if (diff_format == D_SIDEBYSIDE) { 1193 if (color && a > b) 1194 printf("\033[%sm", add_code); 1195 else if (color && c > d) 1196 printf("\033[%sm", del_code); 1197 if (a > b) { 1198 print_space(0, hw + lpad, *pflags); 1199 } else { 1200 nc = fetch(ixold, a, b, f1, '\0', 1, *pflags); 1201 print_space(nc, hw - nc + lpad, *pflags); 1202 } 1203 if (color && a > b) 1204 printf("\033[%sm", add_code); 1205 else if (color && c > d) 1206 printf("\033[%sm", del_code); 1207 printf("%c", (a > b) ? '>' : ((c > d) ? '<' : '|')); 1208 if (color && c > d) 1209 printf("\033[m"); 1210 print_space(hw + lpad + 1, rpad, *pflags); 1211 fetch(ixnew, c, d, f2, '\0', 0, *pflags); 1212 printf("\n"); 1213 } 1214 if (diff_format == D_NORMAL || diff_format == D_IFDEF) { 1215 fetch(ixold, a, b, f1, '<', 1, *pflags); 1216 if (a <= b && c <= d && diff_format == D_NORMAL) 1217 printf("---\n"); 1218 } 1219 if (diff_format != D_GFORMAT && diff_format != D_SIDEBYSIDE) 1220 fetch(ixnew, c, d, f2, diff_format == D_NORMAL ? '>' : '\0', 0, *pflags); 1221 if (edoffset != 0 && diff_format == D_EDIT) { 1222 /* 1223 * A non-zero edoffset value for D_EDIT indicates that the last line 1224 * printed was a bare dot (".") that has been escaped as ".." to 1225 * prevent ed(1) from misinterpreting it. We have to add a 1226 * substitute command to change this back and restart where we left 1227 * off. 1228 */ 1229 printf(".\n"); 1230 printf("%ds/.//\n", a + edoffset - 1); 1231 b = a + edoffset - 1; 1232 a = b + 1; 1233 c += edoffset; 1234 goto restart; 1235 } 1236 if ((diff_format == D_EDIT || diff_format == D_REVERSE) && c <= d) 1237 printf(".\n"); 1238 if (inifdef) { 1239 printf("#endif /* %s */\n", ifdefname); 1240 inifdef = 0; 1241 } 1242} 1243 1244static int 1245fetch(long *f, int a, int b, FILE *lb, int ch, int oldfile, int flags) 1246{ 1247 int i, j, c, lastc, col, nc, newcol; 1248 1249 edoffset = 0; 1250 nc = 0; 1251 col = 0; 1252 /* 1253 * When doing #ifdef's, copy down to current line 1254 * if this is the first file, so that stuff makes it to output. 1255 */ 1256 if ((diff_format == D_IFDEF) && oldfile) { 1257 long curpos = ftell(lb); 1258 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1259 nc = f[a > b ? b : a - 1] - curpos; 1260 for (i = 0; i < nc; i++) 1261 printf("%c", getc(lb)); 1262 } 1263 if (a > b) 1264 return (0); 1265 if (diff_format == D_IFDEF) { 1266 if (inifdef) { 1267 printf("#else /* %s%s */\n", 1268 oldfile == 1 ? "!" : "", ifdefname); 1269 } else { 1270 if (oldfile) 1271 printf("#ifndef %s\n", ifdefname); 1272 else 1273 printf("#ifdef %s\n", ifdefname); 1274 } 1275 inifdef = 1 + oldfile; 1276 } 1277 for (i = a; i <= b; i++) { 1278 fseek(lb, f[i - 1], SEEK_SET); 1279 nc = f[i] - f[i - 1]; 1280 if (diff_format == D_SIDEBYSIDE && hw < nc) 1281 nc = hw; 1282 if (diff_format != D_IFDEF && diff_format != D_GFORMAT && 1283 ch != '\0') { 1284 if (color && (ch == '>' || ch == '+')) 1285 printf("\033[%sm", add_code); 1286 else if (color && (ch == '<' || ch == '-')) 1287 printf("\033[%sm", del_code); 1288 printf("%c", ch); 1289 if (Tflag && (diff_format == D_NORMAL || 1290 diff_format == D_CONTEXT || 1291 diff_format == D_UNIFIED)) 1292 printf("\t"); 1293 else if (diff_format != D_UNIFIED) 1294 printf(" "); 1295 } 1296 col = j = 0; 1297 lastc = '\0'; 1298 while (j < nc && (hw == 0 || col < hw)) { 1299 c = getc(lb); 1300 if (flags & D_STRIPCR && c == '\r') { 1301 if ((c = getc(lb)) == '\n') 1302 j++; 1303 else { 1304 ungetc(c, lb); 1305 c = '\r'; 1306 } 1307 } 1308 if (c == EOF) { 1309 if (diff_format == D_EDIT || 1310 diff_format == D_REVERSE || 1311 diff_format == D_NREVERSE) 1312 warnx("No newline at end of file"); 1313 else 1314 printf("\n\\ No newline at end of file\n"); 1315 return (col); 1316 } 1317 /* 1318 * when using --side-by-side, col needs to be increased 1319 * in any case to keep the columns aligned 1320 */ 1321 if (c == '\t') { 1322 /* 1323 * Calculate where the tab would bring us. 1324 * If it would take us to the end of the 1325 * column, either clip it (if expanding 1326 * tabs) or return right away (if not). 1327 */ 1328 newcol = roundup(col + 1, tabsize); 1329 if ((flags & D_EXPANDTABS) == 0) { 1330 if (hw > 0 && newcol >= hw) 1331 return (col); 1332 printf("\t"); 1333 } else { 1334 if (hw > 0 && newcol > hw) 1335 newcol = hw; 1336 printf("%*s", newcol - col, ""); 1337 } 1338 col = newcol; 1339 } else { 1340 if (diff_format == D_EDIT && j == 1 && c == '\n' && 1341 lastc == '.') { 1342 /* 1343 * Don't print a bare "." line since that will confuse 1344 * ed(1). Print ".." instead and set the, global variable 1345 * edoffset to an offset from which to restart. The 1346 * caller must check the value of edoffset 1347 */ 1348 printf(".\n"); 1349 edoffset = i - a + 1; 1350 return (edoffset); 1351 } 1352 /* when side-by-side, do not print a newline */ 1353 if (diff_format != D_SIDEBYSIDE || c != '\n') { 1354 if (color && c == '\n') 1355 printf("\033[m%c", c); 1356 else 1357 printf("%c", c); 1358 col++; 1359 } 1360 } 1361 1362 j++; 1363 lastc = c; 1364 } 1365 } 1366 if (color && diff_format == D_SIDEBYSIDE) 1367 printf("\033[m"); 1368 return (col); 1369} 1370 1371/* 1372 * Hash function taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. 1373 */ 1374static enum readhash 1375readhash(FILE *f, int flags, unsigned *hash) 1376{ 1377 int i, t, space; 1378 unsigned sum; 1379 1380 sum = 1; 1381 space = 0; 1382 for (i = 0;;) { 1383 switch (t = getc(f)) { 1384 case '\0': 1385 if ((flags & D_FORCEASCII) == 0) 1386 return (RH_BINARY); 1387 goto hashchar; 1388 case '\r': 1389 if (flags & D_STRIPCR) { 1390 t = getc(f); 1391 if (t == '\n') 1392 break; 1393 ungetc(t, f); 1394 } 1395 /* FALLTHROUGH */ 1396 case '\t': 1397 case '\v': 1398 case '\f': 1399 case ' ': 1400 if ((flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) != 0) { 1401 space++; 1402 continue; 1403 } 1404 /* FALLTHROUGH */ 1405 default: 1406 hashchar: 1407 if (space && (flags & D_IGNOREBLANKS) == 0) { 1408 i++; 1409 space = 0; 1410 } 1411 sum = sum * 127 + chrtran(t); 1412 i++; 1413 continue; 1414 case EOF: 1415 if (i == 0) 1416 return (RH_EOF); 1417 /* FALLTHROUGH */ 1418 case '\n': 1419 break; 1420 } 1421 break; 1422 } 1423 *hash = sum; 1424 return (RH_OK); 1425} 1426 1427static int 1428asciifile(FILE *f) 1429{ 1430 unsigned char buf[BUFSIZ]; 1431 size_t cnt; 1432 1433 if (f == NULL) 1434 return (1); 1435 1436 rewind(f); 1437 cnt = fread(buf, 1, sizeof(buf), f); 1438 return (memchr(buf, '\0', cnt) == NULL); 1439} 1440 1441#define begins_with(s, pre) (strncmp(s, pre, sizeof(pre) - 1) == 0) 1442 1443static char * 1444match_function(const long *f, int pos, FILE *fp) 1445{ 1446 unsigned char buf[FUNCTION_CONTEXT_SIZE]; 1447 size_t nc; 1448 int last = lastline; 1449 const char *state = NULL; 1450 1451 lastline = pos; 1452 for (; pos > last; pos--) { 1453 fseek(fp, f[pos - 1], SEEK_SET); 1454 nc = f[pos] - f[pos - 1]; 1455 if (nc >= sizeof(buf)) 1456 nc = sizeof(buf) - 1; 1457 nc = fread(buf, 1, nc, fp); 1458 if (nc == 0) 1459 continue; 1460 buf[nc] = '\0'; 1461 buf[strcspn(buf, "\n")] = '\0'; 1462 if (most_recent_pat != NULL) { 1463 int ret = regexec(&most_recent_re, buf, 0, NULL, 0); 1464 1465 if (ret != 0) 1466 continue; 1467 strlcpy(lastbuf, buf, sizeof(lastbuf)); 1468 lastmatchline = pos; 1469 return (lastbuf); 1470 } else if (isalpha(buf[0]) || buf[0] == '_' || buf[0] == '$' 1471 || buf[0] == '-' || buf[0] == '+') { 1472 if (begins_with(buf, "private:")) { 1473 if (!state) 1474 state = " (private)"; 1475 } else if (begins_with(buf, "protected:")) { 1476 if (!state) 1477 state = " (protected)"; 1478 } else if (begins_with(buf, "public:")) { 1479 if (!state) 1480 state = " (public)"; 1481 } else { 1482 strlcpy(lastbuf, buf, sizeof(lastbuf)); 1483 if (state) 1484 strlcat(lastbuf, state, sizeof(lastbuf)); 1485 lastmatchline = pos; 1486 return (lastbuf); 1487 } 1488 } 1489 } 1490 return (lastmatchline > 0 ? lastbuf : NULL); 1491} 1492 1493/* dump accumulated "context" diff changes */ 1494static void 1495dump_context_vec(FILE *f1, FILE *f2, int flags) 1496{ 1497 struct context_vec *cvp = context_vec_start; 1498 int lowa, upb, lowc, upd, do_output; 1499 int a, b, c, d; 1500 char ch, *f; 1501 1502 if (context_vec_start > context_vec_ptr) 1503 return; 1504 1505 b = d = 0; /* gcc */ 1506 lowa = MAX(1, cvp->a - diff_context); 1507 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1508 lowc = MAX(1, cvp->c - diff_context); 1509 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1510 1511 printf("***************"); 1512 if (flags & (D_PROTOTYPE | D_MATCHLAST)) { 1513 f = match_function(ixold, cvp->a - 1, f1); 1514 if (f != NULL) 1515 printf(" %s", f); 1516 } 1517 printf("\n*** "); 1518 range(lowa, upb, ","); 1519 printf(" ****\n"); 1520 1521 /* 1522 * Output changes to the "old" file. The first loop suppresses 1523 * output if there were no changes to the "old" file (we'll see 1524 * the "old" lines as context in the "new" list). 1525 */ 1526 do_output = 0; 1527 for (; cvp <= context_vec_ptr; cvp++) 1528 if (cvp->a <= cvp->b) { 1529 cvp = context_vec_start; 1530 do_output++; 1531 break; 1532 } 1533 if (do_output) { 1534 while (cvp <= context_vec_ptr) { 1535 a = cvp->a; 1536 b = cvp->b; 1537 c = cvp->c; 1538 d = cvp->d; 1539 1540 if (a <= b && c <= d) 1541 ch = 'c'; 1542 else 1543 ch = (a <= b) ? 'd' : 'a'; 1544 1545 if (ch == 'a') 1546 fetch(ixold, lowa, b, f1, ' ', 0, flags); 1547 else { 1548 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1549 fetch(ixold, a, b, f1, 1550 ch == 'c' ? '!' : '-', 0, flags); 1551 } 1552 lowa = b + 1; 1553 cvp++; 1554 } 1555 fetch(ixold, b + 1, upb, f1, ' ', 0, flags); 1556 } 1557 /* output changes to the "new" file */ 1558 printf("--- "); 1559 range(lowc, upd, ","); 1560 printf(" ----\n"); 1561 1562 do_output = 0; 1563 for (cvp = context_vec_start; cvp <= context_vec_ptr; cvp++) 1564 if (cvp->c <= cvp->d) { 1565 cvp = context_vec_start; 1566 do_output++; 1567 break; 1568 } 1569 if (do_output) { 1570 while (cvp <= context_vec_ptr) { 1571 a = cvp->a; 1572 b = cvp->b; 1573 c = cvp->c; 1574 d = cvp->d; 1575 1576 if (a <= b && c <= d) 1577 ch = 'c'; 1578 else 1579 ch = (a <= b) ? 'd' : 'a'; 1580 1581 if (ch == 'd') 1582 fetch(ixnew, lowc, d, f2, ' ', 0, flags); 1583 else { 1584 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1585 fetch(ixnew, c, d, f2, 1586 ch == 'c' ? '!' : '+', 0, flags); 1587 } 1588 lowc = d + 1; 1589 cvp++; 1590 } 1591 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1592 } 1593 context_vec_ptr = context_vec_start - 1; 1594} 1595 1596/* dump accumulated "unified" diff changes */ 1597static void 1598dump_unified_vec(FILE *f1, FILE *f2, int flags) 1599{ 1600 struct context_vec *cvp = context_vec_start; 1601 int lowa, upb, lowc, upd; 1602 int a, b, c, d; 1603 char ch, *f; 1604 1605 if (context_vec_start > context_vec_ptr) 1606 return; 1607 1608 b = d = 0; /* gcc */ 1609 lowa = MAX(1, cvp->a - diff_context); 1610 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1611 lowc = MAX(1, cvp->c - diff_context); 1612 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1613 1614 printf("@@ -"); 1615 uni_range(lowa, upb); 1616 printf(" +"); 1617 uni_range(lowc, upd); 1618 printf(" @@"); 1619 if (flags & (D_PROTOTYPE | D_MATCHLAST)) { 1620 f = match_function(ixold, cvp->a - 1, f1); 1621 if (f != NULL) 1622 printf(" %s", f); 1623 } 1624 printf("\n"); 1625 1626 /* 1627 * Output changes in "unified" diff format--the old and new lines 1628 * are printed together. 1629 */ 1630 for (; cvp <= context_vec_ptr; cvp++) { 1631 a = cvp->a; 1632 b = cvp->b; 1633 c = cvp->c; 1634 d = cvp->d; 1635 1636 /* 1637 * c: both new and old changes 1638 * d: only changes in the old file 1639 * a: only changes in the new file 1640 */ 1641 if (a <= b && c <= d) 1642 ch = 'c'; 1643 else 1644 ch = (a <= b) ? 'd' : 'a'; 1645 1646 switch (ch) { 1647 case 'c': 1648 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1649 fetch(ixold, a, b, f1, '-', 0, flags); 1650 fetch(ixnew, c, d, f2, '+', 0, flags); 1651 break; 1652 case 'd': 1653 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1654 fetch(ixold, a, b, f1, '-', 0, flags); 1655 break; 1656 case 'a': 1657 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1658 fetch(ixnew, c, d, f2, '+', 0, flags); 1659 break; 1660 } 1661 lowa = b + 1; 1662 lowc = d + 1; 1663 } 1664 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1665 1666 context_vec_ptr = context_vec_start - 1; 1667} 1668 1669static void 1670print_header(const char *file1, const char *file2) 1671{ 1672 const char *time_format; 1673 char buf[256]; 1674 struct tm tm1, tm2, *tm_ptr1, *tm_ptr2; 1675 int nsec1 = stb1.st_mtim.tv_nsec; 1676 int nsec2 = stb2.st_mtim.tv_nsec; 1677 1678 time_format = "%Y-%m-%d %H:%M:%S"; 1679 1680 if (cflag) 1681 time_format = "%c"; 1682 tm_ptr1 = localtime_r(&stb1.st_mtime, &tm1); 1683 tm_ptr2 = localtime_r(&stb2.st_mtime, &tm2); 1684 if (label[0] != NULL) 1685 printf("%s %s\n", diff_format == D_CONTEXT ? "***" : "---", 1686 label[0]); 1687 else { 1688 strftime(buf, sizeof(buf), time_format, tm_ptr1); 1689 printf("%s %s\t%s", diff_format == D_CONTEXT ? "***" : "---", 1690 file1, buf); 1691 if (!cflag) { 1692 strftime(buf, sizeof(buf), "%z", tm_ptr1); 1693 printf(".%.9d %s", nsec1, buf); 1694 } 1695 printf("\n"); 1696 } 1697 if (label[1] != NULL) 1698 printf("%s %s\n", diff_format == D_CONTEXT ? "---" : "+++", 1699 label[1]); 1700 else { 1701 strftime(buf, sizeof(buf), time_format, tm_ptr2); 1702 printf("%s %s\t%s", diff_format == D_CONTEXT ? "---" : "+++", 1703 file2, buf); 1704 if (!cflag) { 1705 strftime(buf, sizeof(buf), "%z", tm_ptr2); 1706 printf(".%.9d %s", nsec2, buf); 1707 } 1708 printf("\n"); 1709 } 1710} 1711 1712/* 1713 * Prints n number of space characters either by using tab 1714 * or single space characters. 1715 * nc is the preceding number of characters 1716 */ 1717static void 1718print_space(int nc, int n, int flags) 1719{ 1720 int col, newcol, tabstop; 1721 1722 col = nc; 1723 newcol = nc + n; 1724 /* first, use tabs if allowed */ 1725 if ((flags & D_EXPANDTABS) == 0) { 1726 while ((tabstop = roundup(col + 1, tabsize)) <= newcol) { 1727 printf("\t"); 1728 col = tabstop; 1729 } 1730 } 1731 /* finish with spaces */ 1732 printf("%*s", newcol - col, ""); 1733} 1734