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 a pair of longest 99 * identical subsequences in the two files. 100 * 101 * The major goal is to generate the match vector J. J[i] is the index of 102 * the line in file1 corresponding to line i file0. J[i] = 0 if there is no 103 * such line in file1. 104 * 105 * Lines are hashed so as to work in core. All potential matches are 106 * located by sorting the lines of each file on the hash (called 107 * ``value''). In particular, this collects the equivalence classes in 108 * file1 together. Subroutine equiv replaces the value of each line in 109 * file0 by the index of the first element of its matching equivalence in 110 * (the reordered) file1. To save space equiv squeezes file1 into a single 111 * array member in which the equivalence classes are simply concatenated, 112 * except that their first members are flagged by changing sign. 113 * 114 * Next the indices that point into member are unsorted into array class 115 * according to the original order of file0. 116 * 117 * The cleverness lies in routine stone. This marches through the lines of 118 * file0, developing a vector klist of "k-candidates". At step i 119 * a k-candidate is a matched pair of lines x,y (x in file0 y in file1) 120 * such that there is a common subsequence of length k between the first 121 * i lines of file0 and the first y lines of file1, but there is no such 122 * subsequence for any smaller y. x is the earliest possible mate to y that 123 * occurs in such a subsequence. 124 * 125 * Whenever any of the members of the equivalence class of lines in file1 126 * matable to a line in file0 has serial number less than the y of some 127 * k-candidate, that k-candidate with the smallest such y is replaced. The 128 * new k-candidate is chained (via pred) to the current k-1 candidate so 129 * that the actual subsequence can be recovered. When a member has serial 130 * number greater that the y of all k-candidates, the klist is extended. At 131 * the end, the longest subsequence is pulled out and placed in the array J 132 * by unravel. 133 * 134 * With J in hand, the matches there recorded are check'ed against reality 135 * to assure that no spurious matches have crept in due to hashing. If they 136 * have, they are broken, and "jackpot" is recorded -- a harmless matter 137 * except that a true match for a spuriously mated line may now be 138 * unnecessarily reported as a change. 139 * 140 * Much of the complexity of the program comes simply from trying to 141 * minimize core utilization and maximize the range of doable problems by 142 * dynamically allocating what is needed and reusing what is not. The core 143 * requirements for problems larger than somewhat are (in words) 144 * 2*length(file0) + length(file1) + 3*(number of k-candidates installed), 145 * typically about 6n words for files of length n. 146 */ 147 148 struct cand { 149 int x; 150 int y; 151 int pred; 152 }; 153 154 static struct line { 155 int serial; 156 int value; 157 } *file[2]; 158 159 /* 160 * The following struct is used to record change information when 161 * doing a "context" or "unified" diff. (see routine "change" to 162 * understand the highly mnemonic field names) 163 */ 164 struct context_vec { 165 int a; /* start line in old file */ 166 int b; /* end line in old file */ 167 int c; /* start line in new file */ 168 int d; /* end line in new file */ 169 }; 170 171 enum readhash { RH_BINARY, RH_OK, RH_EOF }; 172 173 #define MIN_PAD 1 174 static FILE *opentemp(const char *); 175 static void output(char *, FILE *, char *, FILE *, int); 176 static void check(FILE *, FILE *, int); 177 static void range(int, int, const char *); 178 static void uni_range(int, int); 179 static void dump_context_vec(FILE *, FILE *, int); 180 static void dump_unified_vec(FILE *, FILE *, int); 181 static bool prepare(int, FILE *, size_t, int); 182 static void prune(void); 183 static void equiv(struct line *, int, struct line *, int, int *); 184 static void unravel(int); 185 static void unsort(struct line *, int, int *); 186 static void change(char *, FILE *, char *, FILE *, int, int, int, int, int *); 187 static void sort(struct line *, int); 188 static void print_header(const char *, const char *); 189 static void print_space(int, int, int); 190 static bool ignoreline_pattern(char *); 191 static bool ignoreline(char *, bool); 192 static int asciifile(FILE *); 193 static int fetch(long *, int, int, FILE *, int, int, int); 194 static int newcand(int, int, int); 195 static int search(int *, int, int); 196 static int skipline(FILE *); 197 static int isqrt(int); 198 static int stone(int *, int, int *, int *, int); 199 static enum readhash readhash(FILE *, int, unsigned *); 200 static int files_differ(FILE *, FILE *, int); 201 static char *match_function(const long *, int, FILE *); 202 static char *preadline(int, size_t, off_t); 203 204 static int *J; /* will be overlaid on class */ 205 static int *class; /* will be overlaid on file[0] */ 206 static int *klist; /* will be overlaid on file[0] after class */ 207 static int *member; /* will be overlaid on file[1] */ 208 static int clen; 209 static int inifdef; /* whether or not we are in a #ifdef block */ 210 static int len[2]; 211 static int pref, suff; /* length of prefix and suffix */ 212 static int slen[2]; 213 static int anychange; 214 static int hw, padding; /* half width and padding */ 215 static int edoffset; 216 static long *ixnew; /* will be overlaid on file[1] */ 217 static long *ixold; /* will be overlaid on klist */ 218 static struct cand *clist; /* merely a free storage pot for candidates */ 219 static int clistlen; /* the length of clist */ 220 static struct line *sfile[2]; /* shortened by pruning common prefix/suffix */ 221 static int (*chrtran)(int); /* translation table for case-folding */ 222 static struct context_vec *context_vec_start; 223 static struct context_vec *context_vec_end; 224 static struct context_vec *context_vec_ptr; 225 226 #define FUNCTION_CONTEXT_SIZE 55 227 static char lastbuf[FUNCTION_CONTEXT_SIZE]; 228 static int lastline; 229 static int lastmatchline; 230 231 static int 232 clow2low(int c) 233 { 234 235 return (c); 236 } 237 238 static int 239 cup2low(int c) 240 { 241 242 return (tolower(c)); 243 } 244 245 int 246 diffreg(char *file1, char *file2, int flags, int capsicum) 247 { 248 FILE *f1, *f2; 249 int i, rval; 250 struct pr *pr = NULL; 251 cap_rights_t rights_ro; 252 253 f1 = f2 = NULL; 254 rval = D_SAME; 255 anychange = 0; 256 lastline = 0; 257 lastmatchline = 0; 258 context_vec_ptr = context_vec_start - 1; 259 260 /* 261 * hw excludes padding and make sure when -t is not used, 262 * the second column always starts from the closest tab stop 263 */ 264 if (diff_format == D_SIDEBYSIDE) { 265 hw = width >> 1; 266 padding = tabsize - (hw % tabsize); 267 if ((flags & D_EXPANDTABS) != 0 || (padding % tabsize == 0)) 268 padding = MIN_PAD; 269 270 hw = (width >> 1) - 271 ((padding == MIN_PAD) ? (padding << 1) : padding) - 1; 272 } 273 274 275 if (flags & D_IGNORECASE) 276 chrtran = cup2low; 277 else 278 chrtran = clow2low; 279 if (S_ISDIR(stb1.st_mode) != S_ISDIR(stb2.st_mode)) 280 return (S_ISDIR(stb1.st_mode) ? D_MISMATCH1 : D_MISMATCH2); 281 if (strcmp(file1, "-") == 0 && strcmp(file2, "-") == 0) 282 goto closem; 283 284 if (flags & D_EMPTY1) 285 f1 = fopen(_PATH_DEVNULL, "r"); 286 else { 287 if (!S_ISREG(stb1.st_mode)) { 288 if ((f1 = opentemp(file1)) == NULL || 289 fstat(fileno(f1), &stb1) == -1) { 290 warn("%s", file1); 291 rval = D_ERROR; 292 status |= 2; 293 goto closem; 294 } 295 } else if (strcmp(file1, "-") == 0) 296 f1 = stdin; 297 else 298 f1 = fopen(file1, "r"); 299 } 300 if (f1 == NULL) { 301 warn("%s", file1); 302 rval = D_ERROR; 303 status |= 2; 304 goto closem; 305 } 306 307 if (flags & D_EMPTY2) 308 f2 = fopen(_PATH_DEVNULL, "r"); 309 else { 310 if (!S_ISREG(stb2.st_mode)) { 311 if ((f2 = opentemp(file2)) == NULL || 312 fstat(fileno(f2), &stb2) == -1) { 313 warn("%s", file2); 314 rval = D_ERROR; 315 status |= 2; 316 goto closem; 317 } 318 } else if (strcmp(file2, "-") == 0) 319 f2 = stdin; 320 else 321 f2 = fopen(file2, "r"); 322 } 323 if (f2 == NULL) { 324 warn("%s", file2); 325 rval = D_ERROR; 326 status |= 2; 327 goto closem; 328 } 329 330 if (lflag) 331 pr = start_pr(file1, file2); 332 333 if (capsicum) { 334 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); 335 if (caph_rights_limit(fileno(f1), &rights_ro) < 0) 336 err(2, "unable to limit rights on: %s", file1); 337 if (caph_rights_limit(fileno(f2), &rights_ro) < 0) 338 err(2, "unable to limit rights on: %s", file2); 339 if (fileno(f1) == STDIN_FILENO || fileno(f2) == STDIN_FILENO) { 340 /* stdin has already been limited */ 341 if (caph_limit_stderr() == -1) 342 err(2, "unable to limit stderr"); 343 if (caph_limit_stdout() == -1) 344 err(2, "unable to limit stdout"); 345 } else if (caph_limit_stdio() == -1) 346 err(2, "unable to limit stdio"); 347 348 caph_cache_catpages(); 349 caph_cache_tzdata(); 350 if (caph_enter() < 0) 351 err(2, "unable to enter capability mode"); 352 } 353 354 switch (files_differ(f1, f2, flags)) { 355 case 0: 356 goto closem; 357 case 1: 358 break; 359 default: 360 /* error */ 361 rval = D_ERROR; 362 status |= 2; 363 goto closem; 364 } 365 366 if (diff_format == D_BRIEF && ignore_pats == NULL && 367 (flags & (D_FOLDBLANKS|D_IGNOREBLANKS|D_IGNORECASE|D_STRIPCR)) == 0) 368 { 369 rval = D_DIFFER; 370 status |= 1; 371 goto closem; 372 } 373 if ((flags & D_FORCEASCII) != 0) { 374 (void)prepare(0, f1, stb1.st_size, flags); 375 (void)prepare(1, f2, stb2.st_size, flags); 376 } else if (!asciifile(f1) || !asciifile(f2) || 377 !prepare(0, f1, stb1.st_size, flags) || 378 !prepare(1, f2, stb2.st_size, flags)) { 379 rval = D_BINARY; 380 status |= 1; 381 goto closem; 382 } 383 384 prune(); 385 sort(sfile[0], slen[0]); 386 sort(sfile[1], slen[1]); 387 388 member = (int *)file[1]; 389 equiv(sfile[0], slen[0], sfile[1], slen[1], member); 390 member = xreallocarray(member, slen[1] + 2, sizeof(*member)); 391 392 class = (int *)file[0]; 393 unsort(sfile[0], slen[0], class); 394 class = xreallocarray(class, slen[0] + 2, sizeof(*class)); 395 396 klist = xcalloc(slen[0] + 2, sizeof(*klist)); 397 clen = 0; 398 clistlen = 100; 399 clist = xcalloc(clistlen, sizeof(*clist)); 400 i = stone(class, slen[0], member, klist, flags); 401 free(member); 402 free(class); 403 404 J = xreallocarray(J, len[0] + 2, sizeof(*J)); 405 unravel(klist[i]); 406 free(clist); 407 free(klist); 408 409 ixold = xreallocarray(ixold, len[0] + 2, sizeof(*ixold)); 410 ixnew = xreallocarray(ixnew, len[1] + 2, sizeof(*ixnew)); 411 check(f1, f2, flags); 412 output(file1, f1, file2, f2, flags); 413 414 closem: 415 if (pr != NULL) 416 stop_pr(pr); 417 if (anychange) { 418 status |= 1; 419 if (rval == D_SAME) 420 rval = D_DIFFER; 421 } 422 if (f1 != NULL) 423 fclose(f1); 424 if (f2 != NULL) 425 fclose(f2); 426 427 return (rval); 428 } 429 430 /* 431 * Check to see if the given files differ. 432 * Returns 0 if they are the same, 1 if different, and -1 on error. 433 * XXX - could use code from cmp(1) [faster] 434 */ 435 static int 436 files_differ(FILE *f1, FILE *f2, int flags) 437 { 438 char buf1[BUFSIZ], buf2[BUFSIZ]; 439 size_t i, j; 440 441 if ((flags & (D_EMPTY1|D_EMPTY2)) || stb1.st_size != stb2.st_size || 442 (stb1.st_mode & S_IFMT) != (stb2.st_mode & S_IFMT)) 443 return (1); 444 for (;;) { 445 i = fread(buf1, 1, sizeof(buf1), f1); 446 j = fread(buf2, 1, sizeof(buf2), f2); 447 if ((!i && ferror(f1)) || (!j && ferror(f2))) 448 return (-1); 449 if (i != j) 450 return (1); 451 if (i == 0) 452 return (0); 453 if (memcmp(buf1, buf2, i) != 0) 454 return (1); 455 } 456 } 457 458 static FILE * 459 opentemp(const char *f) 460 { 461 char buf[BUFSIZ], tempfile[PATH_MAX]; 462 ssize_t nread; 463 int ifd, ofd; 464 465 if (strcmp(f, "-") == 0) 466 ifd = STDIN_FILENO; 467 else if ((ifd = open(f, O_RDONLY, 0644)) == -1) 468 return (NULL); 469 470 (void)strlcpy(tempfile, _PATH_TMP "/diff.XXXXXXXX", sizeof(tempfile)); 471 472 if ((ofd = mkstemp(tempfile)) == -1) { 473 close(ifd); 474 return (NULL); 475 } 476 unlink(tempfile); 477 while ((nread = read(ifd, buf, BUFSIZ)) > 0) { 478 if (write(ofd, buf, nread) != nread) { 479 close(ifd); 480 close(ofd); 481 return (NULL); 482 } 483 } 484 close(ifd); 485 lseek(ofd, (off_t)0, SEEK_SET); 486 return (fdopen(ofd, "r")); 487 } 488 489 char * 490 splice(char *dir, char *path) 491 { 492 char *tail, *buf; 493 size_t dirlen; 494 495 dirlen = strlen(dir); 496 while (dirlen != 0 && dir[dirlen - 1] == '/') 497 dirlen--; 498 if ((tail = strrchr(path, '/')) == NULL) 499 tail = path; 500 else 501 tail++; 502 xasprintf(&buf, "%.*s/%s", (int)dirlen, dir, tail); 503 return (buf); 504 } 505 506 static bool 507 prepare(int i, FILE *fd, size_t filesize, int flags) 508 { 509 struct line *p; 510 unsigned h; 511 size_t sz, j = 0; 512 enum readhash r; 513 514 rewind(fd); 515 516 sz = MIN(filesize, SIZE_MAX) / 25; 517 if (sz < 100) 518 sz = 100; 519 520 p = xcalloc(sz + 3, sizeof(*p)); 521 while ((r = readhash(fd, flags, &h)) != RH_EOF) 522 switch (r) { 523 case RH_EOF: /* otherwise clang complains */ 524 case RH_BINARY: 525 return (false); 526 case RH_OK: 527 if (j == sz) { 528 sz = sz * 3 / 2; 529 p = xreallocarray(p, sz + 3, sizeof(*p)); 530 } 531 p[++j].value = h; 532 } 533 534 len[i] = j; 535 file[i] = p; 536 537 return (true); 538 } 539 540 static void 541 prune(void) 542 { 543 int i, j; 544 545 for (pref = 0; pref < len[0] && pref < len[1] && 546 file[0][pref + 1].value == file[1][pref + 1].value; 547 pref++) 548 ; 549 for (suff = 0; suff < len[0] - pref && suff < len[1] - pref && 550 file[0][len[0] - suff].value == file[1][len[1] - suff].value; 551 suff++) 552 ; 553 for (j = 0; j < 2; j++) { 554 sfile[j] = file[j] + pref; 555 slen[j] = len[j] - pref - suff; 556 for (i = 0; i <= slen[j]; i++) 557 sfile[j][i].serial = i; 558 } 559 } 560 561 static void 562 equiv(struct line *a, int n, struct line *b, int m, int *c) 563 { 564 int i, j; 565 566 i = j = 1; 567 while (i <= n && j <= m) { 568 if (a[i].value < b[j].value) 569 a[i++].value = 0; 570 else if (a[i].value == b[j].value) 571 a[i++].value = j; 572 else 573 j++; 574 } 575 while (i <= n) 576 a[i++].value = 0; 577 b[m + 1].value = 0; 578 j = 0; 579 while (++j <= m) { 580 c[j] = -b[j].serial; 581 while (b[j + 1].value == b[j].value) { 582 j++; 583 c[j] = b[j].serial; 584 } 585 } 586 c[j] = -1; 587 } 588 589 /* Code taken from ping.c */ 590 static int 591 isqrt(int n) 592 { 593 int y, x = 1; 594 595 if (n == 0) 596 return (0); 597 598 do { /* newton was a stinker */ 599 y = x; 600 x = n / x; 601 x += y; 602 x /= 2; 603 } while ((x - y) > 1 || (x - y) < -1); 604 605 return (x); 606 } 607 608 static int 609 stone(int *a, int n, int *b, int *c, int flags) 610 { 611 int i, k, y, j, l; 612 int oldc, tc, oldl, sq; 613 unsigned numtries, bound; 614 615 if (flags & D_MINIMAL) 616 bound = UINT_MAX; 617 else { 618 sq = isqrt(n); 619 bound = MAX(256, sq); 620 } 621 622 k = 0; 623 c[0] = newcand(0, 0, 0); 624 for (i = 1; i <= n; i++) { 625 j = a[i]; 626 if (j == 0) 627 continue; 628 y = -b[j]; 629 oldl = 0; 630 oldc = c[0]; 631 numtries = 0; 632 do { 633 if (y <= clist[oldc].y) 634 continue; 635 l = search(c, k, y); 636 if (l != oldl + 1) 637 oldc = c[l - 1]; 638 if (l <= k) { 639 if (clist[c[l]].y <= y) 640 continue; 641 tc = c[l]; 642 c[l] = newcand(i, y, oldc); 643 oldc = tc; 644 oldl = l; 645 numtries++; 646 } else { 647 c[l] = newcand(i, y, oldc); 648 k++; 649 break; 650 } 651 } while ((y = b[++j]) > 0 && numtries < bound); 652 } 653 return (k); 654 } 655 656 static int 657 newcand(int x, int y, int pred) 658 { 659 struct cand *q; 660 661 if (clen == clistlen) { 662 clistlen = clistlen * 11 / 10; 663 clist = xreallocarray(clist, clistlen, sizeof(*clist)); 664 } 665 q = clist + clen; 666 q->x = x; 667 q->y = y; 668 q->pred = pred; 669 return (clen++); 670 } 671 672 static int 673 search(int *c, int k, int y) 674 { 675 int i, j, l, t; 676 677 if (clist[c[k]].y < y) /* quick look for typical case */ 678 return (k + 1); 679 i = 0; 680 j = k + 1; 681 for (;;) { 682 l = (i + j) / 2; 683 if (l <= i) 684 break; 685 t = clist[c[l]].y; 686 if (t > y) 687 j = l; 688 else if (t < y) 689 i = l; 690 else 691 return (l); 692 } 693 return (l + 1); 694 } 695 696 static void 697 unravel(int p) 698 { 699 struct cand *q; 700 int i; 701 702 for (i = 0; i <= len[0]; i++) 703 J[i] = i <= pref ? i : 704 i > len[0] - suff ? i + len[1] - len[0] : 0; 705 for (q = clist + p; q->y != 0; q = clist + q->pred) 706 J[q->x + pref] = q->y + pref; 707 } 708 709 /* 710 * Check does double duty: 711 * 1. ferret out any fortuitous correspondences due to confounding by 712 * hashing (which result in "jackpot") 713 * 2. collect random access indexes to the two files 714 */ 715 static void 716 check(FILE *f1, FILE *f2, int flags) 717 { 718 int i, j, jackpot, c, d; 719 long ctold, ctnew; 720 721 rewind(f1); 722 rewind(f2); 723 j = 1; 724 ixold[0] = ixnew[0] = 0; 725 jackpot = 0; 726 ctold = ctnew = 0; 727 for (i = 1; i <= len[0]; i++) { 728 if (J[i] == 0) { 729 ixold[i] = ctold += skipline(f1); 730 continue; 731 } 732 while (j < J[i]) { 733 ixnew[j] = ctnew += skipline(f2); 734 j++; 735 } 736 if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS | D_IGNORECASE | D_STRIPCR)) { 737 for (;;) { 738 c = getc(f1); 739 d = getc(f2); 740 /* 741 * GNU diff ignores a missing newline 742 * in one file for -b or -w. 743 */ 744 if (flags & (D_FOLDBLANKS | D_IGNOREBLANKS)) { 745 if (c == EOF && d == '\n') { 746 ctnew++; 747 break; 748 } else if (c == '\n' && d == EOF) { 749 ctold++; 750 break; 751 } 752 } 753 ctold++; 754 ctnew++; 755 if (flags & D_STRIPCR && (c == '\r' || d == '\r')) { 756 if (c == '\r') { 757 if ((c = getc(f1)) == '\n') { 758 ctold++; 759 } else { 760 ungetc(c, f1); 761 } 762 } 763 if (d == '\r') { 764 if ((d = getc(f2)) == '\n') { 765 ctnew++; 766 } else { 767 ungetc(d, f2); 768 } 769 } 770 break; 771 } 772 if ((flags & D_FOLDBLANKS) && isspace(c) && 773 isspace(d)) { 774 do { 775 if (c == '\n') 776 break; 777 ctold++; 778 } while (isspace(c = getc(f1))); 779 do { 780 if (d == '\n') 781 break; 782 ctnew++; 783 } while (isspace(d = getc(f2))); 784 } else if (flags & D_IGNOREBLANKS) { 785 while (isspace(c) && c != '\n') { 786 c = getc(f1); 787 ctold++; 788 } 789 while (isspace(d) && d != '\n') { 790 d = getc(f2); 791 ctnew++; 792 } 793 } 794 if (chrtran(c) != chrtran(d)) { 795 jackpot++; 796 J[i] = 0; 797 if (c != '\n' && c != EOF) 798 ctold += skipline(f1); 799 if (d != '\n' && c != EOF) 800 ctnew += skipline(f2); 801 break; 802 } 803 if (c == '\n' || c == EOF) 804 break; 805 } 806 } else { 807 for (;;) { 808 ctold++; 809 ctnew++; 810 if ((c = getc(f1)) != (d = getc(f2))) { 811 /* jackpot++; */ 812 J[i] = 0; 813 if (c != '\n' && c != EOF) 814 ctold += skipline(f1); 815 if (d != '\n' && c != EOF) 816 ctnew += skipline(f2); 817 break; 818 } 819 if (c == '\n' || c == EOF) 820 break; 821 } 822 } 823 ixold[i] = ctold; 824 ixnew[j] = ctnew; 825 j++; 826 } 827 for (; j <= len[1]; j++) { 828 ixnew[j] = ctnew += skipline(f2); 829 } 830 /* 831 * if (jackpot) 832 * fprintf(stderr, "jackpot\n"); 833 */ 834 } 835 836 /* shellsort CACM #201 */ 837 static void 838 sort(struct line *a, int n) 839 { 840 struct line *ai, *aim, w; 841 int j, m = 0, k; 842 843 if (n == 0) 844 return; 845 for (j = 1; j <= n; j *= 2) 846 m = 2 * j - 1; 847 for (m /= 2; m != 0; m /= 2) { 848 k = n - m; 849 for (j = 1; j <= k; j++) { 850 for (ai = &a[j]; ai > a; ai -= m) { 851 aim = &ai[m]; 852 if (aim < ai) 853 break; /* wraparound */ 854 if (aim->value > ai[0].value || 855 (aim->value == ai[0].value && 856 aim->serial > ai[0].serial)) 857 break; 858 w.value = ai[0].value; 859 ai[0].value = aim->value; 860 aim->value = w.value; 861 w.serial = ai[0].serial; 862 ai[0].serial = aim->serial; 863 aim->serial = w.serial; 864 } 865 } 866 } 867 } 868 869 static void 870 unsort(struct line *f, int l, int *b) 871 { 872 int *a, i; 873 874 a = xcalloc(l + 1, sizeof(*a)); 875 for (i = 1; i <= l; i++) 876 a[f[i].serial] = f[i].value; 877 for (i = 1; i <= l; i++) 878 b[i] = a[i]; 879 free(a); 880 } 881 882 static int 883 skipline(FILE *f) 884 { 885 int i, c; 886 887 for (i = 1; (c = getc(f)) != '\n' && c != EOF; i++) 888 continue; 889 return (i); 890 } 891 892 static void 893 output(char *file1, FILE *f1, char *file2, FILE *f2, int flags) 894 { 895 int i, j, m, i0, i1, j0, j1, nc; 896 897 rewind(f1); 898 rewind(f2); 899 m = len[0]; 900 J[0] = 0; 901 J[m + 1] = len[1] + 1; 902 if (diff_format != D_EDIT) { 903 for (i0 = 1; i0 <= m; i0 = i1 + 1) { 904 while (i0 <= m && J[i0] == J[i0 - 1] + 1) { 905 if (diff_format == D_SIDEBYSIDE && suppress_common != 1) { 906 nc = fetch(ixold, i0, i0, f1, '\0', 1, flags); 907 print_space(nc, (hw - nc) + (padding << 1) + 1, flags); 908 fetch(ixnew, J[i0], J[i0], f2, '\0', 0, flags); 909 printf("\n"); 910 } 911 i0++; 912 } 913 j0 = J[i0 - 1] + 1; 914 i1 = i0 - 1; 915 while (i1 < m && J[i1 + 1] == 0) 916 i1++; 917 j1 = J[i1 + 1] - 1; 918 J[i1] = j1; 919 920 /* 921 * When using side-by-side, lines from both of the files are 922 * printed. The algorithm used by diff(1) identifies the ranges 923 * in which two files differ. 924 * See the change() function below. 925 * The for loop below consumes the shorter range, whereas one of 926 * the while loops deals with the longer one. 927 */ 928 if (diff_format == D_SIDEBYSIDE) { 929 for (i = i0, j = j0; i <= i1 && j <= j1; i++, j++) 930 change(file1, f1, file2, f2, i, i, j, j, &flags); 931 932 while (i <= i1) { 933 change(file1, f1, file2, f2, i, i, j + 1, j, &flags); 934 i++; 935 } 936 937 while (j <= j1) { 938 change(file1, f1, file2, f2, i + 1, i, j, j, &flags); 939 j++; 940 } 941 } else 942 change(file1, f1, file2, f2, i0, i1, j0, j1, &flags); 943 } 944 } else { 945 for (i0 = m; i0 >= 1; i0 = i1 - 1) { 946 while (i0 >= 1 && J[i0] == J[i0 + 1] - 1 && J[i0] != 0) 947 i0--; 948 j0 = J[i0 + 1] - 1; 949 i1 = i0 + 1; 950 while (i1 > 1 && J[i1 - 1] == 0) 951 i1--; 952 j1 = J[i1 - 1] + 1; 953 J[i1] = j1; 954 change(file1, f1, file2, f2, i1, i0, j1, j0, &flags); 955 } 956 } 957 if (m == 0) 958 change(file1, f1, file2, f2, 1, 0, 1, len[1], &flags); 959 if (diff_format == D_IFDEF || diff_format == D_GFORMAT) { 960 for (;;) { 961 #define c i0 962 if ((c = getc(f1)) == EOF) 963 return; 964 printf("%c", c); 965 } 966 #undef c 967 } 968 if (anychange != 0) { 969 if (diff_format == D_CONTEXT) 970 dump_context_vec(f1, f2, flags); 971 else if (diff_format == D_UNIFIED) 972 dump_unified_vec(f1, f2, flags); 973 } 974 } 975 976 static void 977 range(int a, int b, const char *separator) 978 { 979 printf("%d", a > b ? b : a); 980 if (a < b) 981 printf("%s%d", separator, b); 982 } 983 984 static void 985 uni_range(int a, int b) 986 { 987 if (a < b) 988 printf("%d,%d", a, b - a + 1); 989 else if (a == b) 990 printf("%d", b); 991 else 992 printf("%d,0", b); 993 } 994 995 static char * 996 preadline(int fd, size_t rlen, off_t off) 997 { 998 char *line; 999 ssize_t nr; 1000 1001 line = xmalloc(rlen + 1); 1002 if ((nr = pread(fd, line, rlen, off)) == -1) 1003 err(2, "preadline"); 1004 if (nr > 0 && line[nr-1] == '\n') 1005 nr--; 1006 line[nr] = '\0'; 1007 return (line); 1008 } 1009 1010 static bool 1011 ignoreline_pattern(char *line) 1012 { 1013 int ret; 1014 1015 ret = regexec(&ignore_re, line, 0, NULL, 0); 1016 free(line); 1017 return (ret == 0); /* if it matched, it should be ignored. */ 1018 } 1019 1020 static bool 1021 ignoreline(char *line, bool skip_blanks) 1022 { 1023 1024 if (ignore_pats != NULL && skip_blanks) 1025 return (ignoreline_pattern(line) || *line == '\0'); 1026 if (ignore_pats != NULL) 1027 return (ignoreline_pattern(line)); 1028 if (skip_blanks) 1029 return (*line == '\0'); 1030 /* No ignore criteria specified */ 1031 return (false); 1032 } 1033 1034 /* 1035 * Indicate that there is a difference between lines a and b of the from file 1036 * to get to lines c to d of the to file. If a is greater then b then there 1037 * are no lines in the from file involved and this means that there were 1038 * lines appended (beginning at b). If c is greater than d then there are 1039 * lines missing from the to file. 1040 */ 1041 static void 1042 change(char *file1, FILE *f1, char *file2, FILE *f2, int a, int b, int c, int d, 1043 int *pflags) 1044 { 1045 static size_t max_context = 64; 1046 long curpos; 1047 int i, nc; 1048 const char *walk; 1049 bool skip_blanks; 1050 1051 skip_blanks = (*pflags & D_SKIPBLANKLINES); 1052 restart: 1053 if ((diff_format != D_IFDEF || diff_format == D_GFORMAT) && 1054 a > b && c > d) 1055 return; 1056 if (ignore_pats != NULL || skip_blanks) { 1057 char *line; 1058 /* 1059 * All lines in the change, insert, or delete must match an ignore 1060 * pattern for the change to be ignored. 1061 */ 1062 if (a <= b) { /* Changes and deletes. */ 1063 for (i = a; i <= b; i++) { 1064 line = preadline(fileno(f1), 1065 ixold[i] - ixold[i - 1], ixold[i - 1]); 1066 if (!ignoreline(line, skip_blanks)) 1067 goto proceed; 1068 } 1069 } 1070 if (a > b || c <= d) { /* Changes and inserts. */ 1071 for (i = c; i <= d; i++) { 1072 line = preadline(fileno(f2), 1073 ixnew[i] - ixnew[i - 1], ixnew[i - 1]); 1074 if (!ignoreline(line, skip_blanks)) 1075 goto proceed; 1076 } 1077 } 1078 return; 1079 } 1080 proceed: 1081 if (*pflags & D_HEADER && diff_format != D_BRIEF) { 1082 printf("%s %s %s\n", diffargs, file1, file2); 1083 *pflags &= ~D_HEADER; 1084 } 1085 if (diff_format == D_CONTEXT || diff_format == D_UNIFIED) { 1086 /* 1087 * Allocate change records as needed. 1088 */ 1089 if (context_vec_ptr == context_vec_end - 1) { 1090 ptrdiff_t offset = context_vec_ptr - context_vec_start; 1091 max_context <<= 1; 1092 context_vec_start = xreallocarray(context_vec_start, 1093 max_context, sizeof(*context_vec_start)); 1094 context_vec_end = context_vec_start + max_context; 1095 context_vec_ptr = context_vec_start + offset; 1096 } 1097 if (anychange == 0) { 1098 /* 1099 * Print the context/unidiff header first time through. 1100 */ 1101 print_header(file1, file2); 1102 anychange = 1; 1103 } else if (a > context_vec_ptr->b + (2 * diff_context) + 1 && 1104 c > context_vec_ptr->d + (2 * diff_context) + 1) { 1105 /* 1106 * If this change is more than 'diff_context' lines from the 1107 * previous change, dump the record and reset it. 1108 */ 1109 if (diff_format == D_CONTEXT) 1110 dump_context_vec(f1, f2, *pflags); 1111 else 1112 dump_unified_vec(f1, f2, *pflags); 1113 } 1114 context_vec_ptr++; 1115 context_vec_ptr->a = a; 1116 context_vec_ptr->b = b; 1117 context_vec_ptr->c = c; 1118 context_vec_ptr->d = d; 1119 return; 1120 } 1121 if (anychange == 0) 1122 anychange = 1; 1123 switch (diff_format) { 1124 case D_BRIEF: 1125 return; 1126 case D_NORMAL: 1127 case D_EDIT: 1128 range(a, b, ","); 1129 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1130 if (diff_format == D_NORMAL) 1131 range(c, d, ","); 1132 printf("\n"); 1133 break; 1134 case D_REVERSE: 1135 printf("%c", a > b ? 'a' : c > d ? 'd' : 'c'); 1136 range(a, b, " "); 1137 printf("\n"); 1138 break; 1139 case D_NREVERSE: 1140 if (a > b) 1141 printf("a%d %d\n", b, d - c + 1); 1142 else { 1143 printf("d%d %d\n", a, b - a + 1); 1144 if (!(c > d)) 1145 /* add changed lines */ 1146 printf("a%d %d\n", b, d - c + 1); 1147 } 1148 break; 1149 } 1150 if (diff_format == D_GFORMAT) { 1151 curpos = ftell(f1); 1152 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1153 nc = ixold[a > b ? b : a - 1] - curpos; 1154 for (i = 0; i < nc; i++) 1155 printf("%c", getc(f1)); 1156 for (walk = group_format; *walk != '\0'; walk++) { 1157 if (*walk == '%') { 1158 walk++; 1159 switch (*walk) { 1160 case '<': 1161 fetch(ixold, a, b, f1, '<', 1, *pflags); 1162 break; 1163 case '>': 1164 fetch(ixnew, c, d, f2, '>', 0, *pflags); 1165 break; 1166 default: 1167 printf("%%%c", *walk); 1168 break; 1169 } 1170 continue; 1171 } 1172 printf("%c", *walk); 1173 } 1174 } 1175 if (diff_format == D_SIDEBYSIDE) { 1176 if (a > b) { 1177 print_space(0, hw + padding , *pflags); 1178 } else { 1179 nc = fetch(ixold, a, b, f1, '\0', 1, *pflags); 1180 print_space(nc, hw - nc + padding, *pflags); 1181 } 1182 printf("%c", (a > b) ? '>' : ((c > d) ? '<' : '|')); 1183 print_space(hw + padding + 1 , padding, *pflags); 1184 fetch(ixnew, c, d, f2, '\0', 0, *pflags); 1185 printf("\n"); 1186 } 1187 if (diff_format == D_NORMAL || diff_format == D_IFDEF) { 1188 fetch(ixold, a, b, f1, '<', 1, *pflags); 1189 if (a <= b && c <= d && diff_format == D_NORMAL) 1190 printf("---\n"); 1191 } 1192 if (diff_format != D_GFORMAT && diff_format != D_SIDEBYSIDE) 1193 fetch(ixnew, c, d, f2, diff_format == D_NORMAL ? '>' : '\0', 0, *pflags); 1194 if (edoffset != 0 && diff_format == D_EDIT) { 1195 /* 1196 * A non-zero edoffset value for D_EDIT indicates that the last line 1197 * printed was a bare dot (".") that has been escaped as ".." to 1198 * prevent ed(1) from misinterpreting it. We have to add a 1199 * substitute command to change this back and restart where we left 1200 * off. 1201 */ 1202 printf(".\n"); 1203 printf("%ds/.//\n", a + edoffset - 1); 1204 b = a + edoffset - 1; 1205 a = b + 1; 1206 c += edoffset; 1207 goto restart; 1208 } 1209 if ((diff_format == D_EDIT || diff_format == D_REVERSE) && c <= d) 1210 printf(".\n"); 1211 if (inifdef) { 1212 printf("#endif /* %s */\n", ifdefname); 1213 inifdef = 0; 1214 } 1215 } 1216 1217 static int 1218 fetch(long *f, int a, int b, FILE *lb, int ch, int oldfile, int flags) 1219 { 1220 int i, j, c, lastc, col, nc, newcol; 1221 1222 edoffset = 0; 1223 nc = 0; 1224 /* 1225 * When doing #ifdef's, copy down to current line 1226 * if this is the first file, so that stuff makes it to output. 1227 */ 1228 if ((diff_format == D_IFDEF) && oldfile) { 1229 long curpos = ftell(lb); 1230 /* print through if append (a>b), else to (nb: 0 vs 1 orig) */ 1231 nc = f[a > b ? b : a - 1] - curpos; 1232 for (i = 0; i < nc; i++) 1233 printf("%c", getc(lb)); 1234 } 1235 if (a > b) 1236 return (0); 1237 if (diff_format == D_IFDEF) { 1238 if (inifdef) { 1239 printf("#else /* %s%s */\n", 1240 oldfile == 1 ? "!" : "", ifdefname); 1241 } else { 1242 if (oldfile) 1243 printf("#ifndef %s\n", ifdefname); 1244 else 1245 printf("#ifdef %s\n", ifdefname); 1246 } 1247 inifdef = 1 + oldfile; 1248 } 1249 for (i = a; i <= b; i++) { 1250 fseek(lb, f[i - 1], SEEK_SET); 1251 nc = f[i] - f[i - 1]; 1252 if (diff_format == D_SIDEBYSIDE && hw < nc) 1253 nc = hw; 1254 if (diff_format != D_IFDEF && diff_format != D_GFORMAT && 1255 ch != '\0') { 1256 printf("%c", ch); 1257 if (Tflag && (diff_format == D_NORMAL || 1258 diff_format == D_CONTEXT || 1259 diff_format == D_UNIFIED)) 1260 printf("\t"); 1261 else if (diff_format != D_UNIFIED) 1262 printf(" "); 1263 } 1264 col = 0; 1265 for (j = 0, lastc = '\0'; j < nc; j++, lastc = c) { 1266 c = getc(lb); 1267 if (flags & D_STRIPCR && c == '\r') { 1268 if ((c = getc(lb)) == '\n') 1269 j++; 1270 else { 1271 ungetc(c, lb); 1272 c = '\r'; 1273 } 1274 } 1275 if (c == 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 file\n"); 1282 return (col); 1283 } 1284 /* 1285 * when using --side-by-side, col needs to be increased 1286 * in any case to keep the columns aligned 1287 */ 1288 if (c == '\t') { 1289 if (flags & D_EXPANDTABS) { 1290 newcol = ((col / tabsize) + 1) * tabsize; 1291 do { 1292 if (diff_format == D_SIDEBYSIDE) 1293 j++; 1294 printf(" "); 1295 } while (++col < newcol && j < nc); 1296 } else { 1297 if (diff_format == D_SIDEBYSIDE) { 1298 if ((j + tabsize) > nc) { 1299 printf("%*s", nc - j, ""); 1300 j = col = nc; 1301 } else { 1302 printf("\t"); 1303 col += tabsize - 1; 1304 j += tabsize - 1; 1305 } 1306 } else { 1307 printf("\t"); 1308 col++; 1309 } 1310 } 1311 } else { 1312 if (diff_format == D_EDIT && j == 1 && c == '\n' && 1313 lastc == '.') { 1314 /* 1315 * Don't print a bare "." line since that will confuse 1316 * ed(1). Print ".." instead and set the, global variable 1317 * edoffset to an offset from which to restart. The 1318 * caller must check the value of edoffset 1319 */ 1320 printf(".\n"); 1321 edoffset = i - a + 1; 1322 return (edoffset); 1323 } 1324 /* when side-by-side, do not print a newline */ 1325 if (diff_format != D_SIDEBYSIDE || c != '\n') { 1326 printf("%c", c); 1327 col++; 1328 } 1329 } 1330 } 1331 } 1332 return (col); 1333 } 1334 1335 /* 1336 * Hash function taken from Robert Sedgewick, Algorithms in C, 3d ed., p 578. 1337 */ 1338 static enum readhash 1339 readhash(FILE *f, int flags, unsigned *hash) 1340 { 1341 int i, t, space; 1342 unsigned sum; 1343 1344 sum = 1; 1345 space = 0; 1346 for (i = 0;;) { 1347 switch (t = getc(f)) { 1348 case '\0': 1349 if ((flags & D_FORCEASCII) == 0) 1350 return (RH_BINARY); 1351 case '\r': 1352 if (flags & D_STRIPCR) { 1353 t = getc(f); 1354 if (t == '\n') 1355 break; 1356 ungetc(t, f); 1357 } 1358 /* FALLTHROUGH */ 1359 case '\t': 1360 case '\v': 1361 case '\f': 1362 case ' ': 1363 if ((flags & (D_FOLDBLANKS|D_IGNOREBLANKS)) != 0) { 1364 space++; 1365 continue; 1366 } 1367 /* FALLTHROUGH */ 1368 default: 1369 if (space && (flags & D_IGNOREBLANKS) == 0) { 1370 i++; 1371 space = 0; 1372 } 1373 sum = sum * 127 + chrtran(t); 1374 i++; 1375 continue; 1376 case EOF: 1377 if (i == 0) 1378 return (RH_EOF); 1379 /* FALLTHROUGH */ 1380 case '\n': 1381 break; 1382 } 1383 break; 1384 } 1385 *hash = sum; 1386 return (RH_OK); 1387 } 1388 1389 static int 1390 asciifile(FILE *f) 1391 { 1392 unsigned char buf[BUFSIZ]; 1393 size_t cnt; 1394 1395 if (f == NULL) 1396 return (1); 1397 1398 rewind(f); 1399 cnt = fread(buf, 1, sizeof(buf), f); 1400 return (memchr(buf, '\0', cnt) == NULL); 1401 } 1402 1403 #define begins_with(s, pre) (strncmp(s, pre, sizeof(pre) - 1) == 0) 1404 1405 static char * 1406 match_function(const long *f, int pos, FILE *fp) 1407 { 1408 unsigned char buf[FUNCTION_CONTEXT_SIZE]; 1409 size_t nc; 1410 int last = lastline; 1411 const char *state = NULL; 1412 1413 lastline = pos; 1414 while (pos > last) { 1415 fseek(fp, f[pos - 1], SEEK_SET); 1416 nc = f[pos] - f[pos - 1]; 1417 if (nc >= sizeof(buf)) 1418 nc = sizeof(buf) - 1; 1419 nc = fread(buf, 1, nc, fp); 1420 if (nc > 0) { 1421 buf[nc] = '\0'; 1422 buf[strcspn(buf, "\n")] = '\0'; 1423 if (isalpha(buf[0]) || buf[0] == '_' || buf[0] == '$') { 1424 if (begins_with(buf, "private:")) { 1425 if (!state) 1426 state = " (private)"; 1427 } else if (begins_with(buf, "protected:")) { 1428 if (!state) 1429 state = " (protected)"; 1430 } else if (begins_with(buf, "public:")) { 1431 if (!state) 1432 state = " (public)"; 1433 } else { 1434 strlcpy(lastbuf, buf, sizeof(lastbuf)); 1435 if (state) 1436 strlcat(lastbuf, state, sizeof(lastbuf)); 1437 lastmatchline = pos; 1438 return (lastbuf); 1439 } 1440 } 1441 } 1442 pos--; 1443 } 1444 return (lastmatchline > 0 ? lastbuf : NULL); 1445 } 1446 1447 /* dump accumulated "context" diff changes */ 1448 static void 1449 dump_context_vec(FILE *f1, FILE *f2, int flags) 1450 { 1451 struct context_vec *cvp = context_vec_start; 1452 int lowa, upb, lowc, upd, do_output; 1453 int a, b, c, d; 1454 char ch, *f; 1455 1456 if (context_vec_start > context_vec_ptr) 1457 return; 1458 1459 b = d = 0; /* gcc */ 1460 lowa = MAX(1, cvp->a - diff_context); 1461 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1462 lowc = MAX(1, cvp->c - diff_context); 1463 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1464 1465 printf("***************"); 1466 if ((flags & D_PROTOTYPE)) { 1467 f = match_function(ixold, lowa - 1, f1); 1468 if (f != NULL) 1469 printf(" %s", f); 1470 } 1471 printf("\n*** "); 1472 range(lowa, upb, ","); 1473 printf(" ****\n"); 1474 1475 /* 1476 * Output changes to the "old" file. The first loop suppresses 1477 * output if there were no changes to the "old" file (we'll see 1478 * the "old" lines as context in the "new" list). 1479 */ 1480 do_output = 0; 1481 for (; cvp <= context_vec_ptr; cvp++) 1482 if (cvp->a <= cvp->b) { 1483 cvp = context_vec_start; 1484 do_output++; 1485 break; 1486 } 1487 if (do_output) { 1488 while (cvp <= context_vec_ptr) { 1489 a = cvp->a; 1490 b = cvp->b; 1491 c = cvp->c; 1492 d = cvp->d; 1493 1494 if (a <= b && c <= d) 1495 ch = 'c'; 1496 else 1497 ch = (a <= b) ? 'd' : 'a'; 1498 1499 if (ch == 'a') 1500 fetch(ixold, lowa, b, f1, ' ', 0, flags); 1501 else { 1502 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1503 fetch(ixold, a, b, f1, 1504 ch == 'c' ? '!' : '-', 0, flags); 1505 } 1506 lowa = b + 1; 1507 cvp++; 1508 } 1509 fetch(ixold, b + 1, upb, f1, ' ', 0, flags); 1510 } 1511 /* output changes to the "new" file */ 1512 printf("--- "); 1513 range(lowc, upd, ","); 1514 printf(" ----\n"); 1515 1516 do_output = 0; 1517 for (cvp = context_vec_start; cvp <= context_vec_ptr; cvp++) 1518 if (cvp->c <= cvp->d) { 1519 cvp = context_vec_start; 1520 do_output++; 1521 break; 1522 } 1523 if (do_output) { 1524 while (cvp <= context_vec_ptr) { 1525 a = cvp->a; 1526 b = cvp->b; 1527 c = cvp->c; 1528 d = cvp->d; 1529 1530 if (a <= b && c <= d) 1531 ch = 'c'; 1532 else 1533 ch = (a <= b) ? 'd' : 'a'; 1534 1535 if (ch == 'd') 1536 fetch(ixnew, lowc, d, f2, ' ', 0, flags); 1537 else { 1538 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1539 fetch(ixnew, c, d, f2, 1540 ch == 'c' ? '!' : '+', 0, flags); 1541 } 1542 lowc = d + 1; 1543 cvp++; 1544 } 1545 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1546 } 1547 context_vec_ptr = context_vec_start - 1; 1548 } 1549 1550 /* dump accumulated "unified" diff changes */ 1551 static void 1552 dump_unified_vec(FILE *f1, FILE *f2, int flags) 1553 { 1554 struct context_vec *cvp = context_vec_start; 1555 int lowa, upb, lowc, upd; 1556 int a, b, c, d; 1557 char ch, *f; 1558 1559 if (context_vec_start > context_vec_ptr) 1560 return; 1561 1562 b = d = 0; /* gcc */ 1563 lowa = MAX(1, cvp->a - diff_context); 1564 upb = MIN(len[0], context_vec_ptr->b + diff_context); 1565 lowc = MAX(1, cvp->c - diff_context); 1566 upd = MIN(len[1], context_vec_ptr->d + diff_context); 1567 1568 printf("@@ -"); 1569 uni_range(lowa, upb); 1570 printf(" +"); 1571 uni_range(lowc, upd); 1572 printf(" @@"); 1573 if ((flags & D_PROTOTYPE)) { 1574 f = match_function(ixold, lowa - 1, f1); 1575 if (f != NULL) 1576 printf(" %s", f); 1577 } 1578 printf("\n"); 1579 1580 /* 1581 * Output changes in "unified" diff format--the old and new lines 1582 * are printed together. 1583 */ 1584 for (; cvp <= context_vec_ptr; cvp++) { 1585 a = cvp->a; 1586 b = cvp->b; 1587 c = cvp->c; 1588 d = cvp->d; 1589 1590 /* 1591 * c: both new and old changes 1592 * d: only changes in the old file 1593 * a: only changes in the new file 1594 */ 1595 if (a <= b && c <= d) 1596 ch = 'c'; 1597 else 1598 ch = (a <= b) ? 'd' : 'a'; 1599 1600 switch (ch) { 1601 case 'c': 1602 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1603 fetch(ixold, a, b, f1, '-', 0, flags); 1604 fetch(ixnew, c, d, f2, '+', 0, flags); 1605 break; 1606 case 'd': 1607 fetch(ixold, lowa, a - 1, f1, ' ', 0, flags); 1608 fetch(ixold, a, b, f1, '-', 0, flags); 1609 break; 1610 case 'a': 1611 fetch(ixnew, lowc, c - 1, f2, ' ', 0, flags); 1612 fetch(ixnew, c, d, f2, '+', 0, flags); 1613 break; 1614 } 1615 lowa = b + 1; 1616 lowc = d + 1; 1617 } 1618 fetch(ixnew, d + 1, upd, f2, ' ', 0, flags); 1619 1620 context_vec_ptr = context_vec_start - 1; 1621 } 1622 1623 static void 1624 print_header(const char *file1, const char *file2) 1625 { 1626 const char *time_format; 1627 char buf1[256]; 1628 char buf2[256]; 1629 char end1[10]; 1630 char end2[10]; 1631 struct tm tm1, tm2, *tm_ptr1, *tm_ptr2; 1632 int nsec1 = stb1.st_mtim.tv_nsec; 1633 int nsec2 = stb2.st_mtim.tv_nsec; 1634 1635 time_format = "%Y-%m-%d %H:%M:%S"; 1636 1637 if (cflag) 1638 time_format = "%c"; 1639 tm_ptr1 = localtime_r(&stb1.st_mtime, &tm1); 1640 tm_ptr2 = localtime_r(&stb2.st_mtime, &tm2); 1641 strftime(buf1, 256, time_format, tm_ptr1); 1642 strftime(buf2, 256, time_format, tm_ptr2); 1643 if (!cflag) { 1644 strftime(end1, 10, "%z", tm_ptr1); 1645 strftime(end2, 10, "%z", tm_ptr2); 1646 sprintf(buf1, "%s.%.9d %s", buf1, nsec1, end1); 1647 sprintf(buf2, "%s.%.9d %s", buf2, nsec2, end2); 1648 } 1649 if (label[0] != NULL) 1650 printf("%s %s\n", diff_format == D_CONTEXT ? "***" : "---", 1651 label[0]); 1652 else 1653 printf("%s %s\t%s\n", diff_format == D_CONTEXT ? "***" : "---", 1654 file1, buf1); 1655 if (label[1] != NULL) 1656 printf("%s %s\n", diff_format == D_CONTEXT ? "---" : "+++", 1657 label[1]); 1658 else 1659 printf("%s %s\t%s\n", diff_format == D_CONTEXT ? "---" : "+++", 1660 file2, buf2); 1661 } 1662 1663 /* 1664 * Prints n number of space characters either by using tab 1665 * or single space characters. 1666 * nc is the preceding number of characters 1667 */ 1668 static void 1669 print_space(int nc, int n, int flags) { 1670 int i, col; 1671 1672 col = n; 1673 if ((flags & D_EXPANDTABS) == 0) { 1674 /* first tabstop may be closer than tabsize */ 1675 i = tabsize - (nc % tabsize); 1676 while (col >= tabsize) { 1677 printf("\t"); 1678 col -= i; 1679 i = tabsize; 1680 } 1681 } 1682 printf("%*s", col, ""); 1683 } 1684