1 /* $OpenBSD: diff3prog.c,v 1.11 2009/10/27 23:59:37 deraadt Exp $ */ 2 3 /* 4 * SPDX-License-Identifier: Caldera-no-preamble AND BSD-3-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/types.h> 68 #include <sys/capsicum.h> 69 #include <sys/procdesc.h> 70 #include <sys/wait.h> 71 72 #include <assert.h> 73 #include <capsicum_helpers.h> 74 #include <ctype.h> 75 #include <err.h> 76 #include <fcntl.h> 77 #include <getopt.h> 78 #include <inttypes.h> 79 #include <limits.h> 80 #include <spawn.h> 81 #include <stdio.h> 82 #include <stdlib.h> 83 #include <string.h> 84 #include <unistd.h> 85 86 extern char **environ; 87 /* 88 * "from" is first in range of changed lines; "to" is last+1 89 * from=to=line after point of insertion for added lines. 90 */ 91 struct range { 92 int from; 93 int to; 94 }; 95 96 enum difftype { 97 DIFF_NONE, 98 DIFF_TYPE1, 99 DIFF_TYPE2, 100 DIFF_TYPE3, 101 }; 102 103 struct diff { 104 enum difftype type; 105 106 /* Ranges as lines */ 107 struct range old; 108 struct range new; 109 }; 110 111 #define EFLAG_NONE 0 112 #define EFLAG_OVERLAP 1 113 #define EFLAG_NOOVERLAP 2 114 #define EFLAG_UNMERGED 3 115 116 static size_t szchanges; 117 118 static struct diff *d13; 119 static struct diff *d23; 120 /* 121 * "de" is used to gather editing scripts. These are later spewed out in 122 * reverse order. Its first element must be all zero, the "old" and "new" 123 * components of "de" contain line positions. Array overlap indicates which 124 * sections in "de" correspond to lines that are different in all three files. 125 */ 126 static struct diff *de; 127 static char *overlap; 128 static int *de_delta; /* file1-file3 line number delta per edit */ 129 static int overlapcnt; 130 static FILE *fp[3]; 131 static int cline[3]; /* # of the last-read line in each file (0-2) */ 132 /* 133 * The latest known correspondence between line numbers of the 3 files 134 * is stored in last[1-3]; 135 */ 136 static int last[4]; 137 static int Aflag, eflag, iflag, mflag, Tflag; 138 static int oflag; /* indicates whether to mark overlaps (-E or -X) */ 139 static int strip_cr; 140 static char *f1mark, *f2mark, *f3mark; 141 static const char *oldmark = "<<<<<<<"; 142 static const char *orgmark = "|||||||"; 143 static const char *newmark = ">>>>>>>"; 144 static const char *divider = "======="; 145 146 static bool duplicate(struct range *, struct range *); 147 static int edit(struct diff *, bool, int, enum difftype); 148 static char *getchange(FILE *); 149 static char *get_line(FILE *, size_t *); 150 static int readin(int fd, struct diff **); 151 static int skip(int, int, const char *); 152 static void change(int, struct range *, bool); 153 static void keep(int, struct range *); 154 static void merge(int, int); 155 static void prange(struct range *, bool); 156 static void repos(int); 157 static void separate(const char *); 158 static void edscript(int) __dead2; 159 static void Ascript(int) __dead2; 160 static void mergescript(int, int) __dead2; 161 static void increase(void); 162 static void usage(void); 163 static void printrange(FILE *, struct range *); 164 165 static const char diff3_version[] = "FreeBSD diff3 20260213"; 166 167 enum { 168 DIFFPROG_OPT, 169 STRIPCR_OPT, 170 HELP_OPT, 171 VERSION_OPT 172 }; 173 174 #define DIFF_PATH "/usr/bin/diff" 175 176 #define OPTIONS "3aAeEiL:mTxX" 177 static struct option longopts[] = { 178 { "ed", no_argument, NULL, 'e' }, 179 { "show-overlap", no_argument, NULL, 'E' }, 180 { "overlap-only", no_argument, NULL, 'x' }, 181 { "initial-tab", no_argument, NULL, 'T' }, 182 { "text", no_argument, NULL, 'a' }, 183 { "strip-trailing-cr", no_argument, NULL, STRIPCR_OPT }, 184 { "show-all", no_argument, NULL, 'A' }, 185 { "easy-only", no_argument, NULL, '3' }, 186 { "merge", no_argument, NULL, 'm' }, 187 { "label", required_argument, NULL, 'L' }, 188 { "diff-program", required_argument, NULL, DIFFPROG_OPT }, 189 { "help", no_argument, NULL, HELP_OPT}, 190 { "version", no_argument, NULL, VERSION_OPT} 191 }; 192 193 static void 194 usage(void) 195 { 196 fprintf(stderr, "usage: diff3 [-3aAeEimTxX] [-L label1] [-L label2] " 197 "[-L label3] file1 file2 file3\n"); 198 } 199 200 static int 201 strtoi(char *str, char **end) 202 { 203 intmax_t num; 204 205 errno = 0; 206 num = strtoimax(str, end, 10); 207 if ((end != NULL && *end == str) || 208 num < 0 || num > INT_MAX || 209 errno == EINVAL || errno == ERANGE) 210 err(2, "error in diff output"); 211 return (int)num; 212 } 213 214 /* 215 * Read diff hunks into the array pointed to by *dd. 216 * 217 * The output from `diff foo bar` consists of a series of hunks describing 218 * an addition (lines in bar not present in foo), change (lines in bar 219 * different from lines in foo), or deletion (lines in foo not present in 220 * bar). Each record starts with a line of the form: 221 * 222 * a[,b]xc[,d] 223 * 224 * where a, b, c, and d are nonnegative integers (b and d are printed only 225 * if they differ from a and c, respectively), and x is either 'a' for an 226 * addition, 'c' for a change, or 'd' for a deletion. This is then 227 * followed by a series of lines (which we ignore) giving the added, 228 * changed, or deleted text. 229 * 230 * For an addition, a == b is the last line in 'foo' before the addition, 231 * while c through d is the range of lines in 'bar' to be added to 'foo'. 232 * 233 * For a change, a through b is the range of lines in 'foo' to be replaced 234 * and c through d is the range of lines in 'bar' to replace them with. 235 * 236 * For a deletion, a through b is the range of lines in 'foo' to remove 237 * and c == d is the line in 'bar' which corresponds to the last line 238 * before the deletion. 239 * 240 * The observant reader will have noticed that x is not really needed and 241 * that we can fully describe any hunk using only a, b, c, and d: 242 * 243 * - an addition replaces a zero-length range in one file with a 244 * non-zero-length range from the other 245 * 246 * - a change replaces a non-zero-length range in one file with a 247 * non-zero-length range from the other 248 * 249 * - a deletion replaces a non-zero-length range in one file with a 250 * zero-length range from the other 251 */ 252 static int 253 readin(int fd, struct diff **dd) 254 { 255 int a, b, c, d; 256 int i; 257 char kind, *p; 258 FILE *f; 259 260 f = fdopen(fd, "r"); 261 if (f == NULL) 262 err(2, "fdopen"); 263 for (i = 0; (p = getchange(f)) != NULL; i++) { 264 if ((size_t)i >= szchanges - 1) 265 increase(); 266 267 a = b = strtoi(p, &p); 268 if (*p == ',') 269 b = strtoi(p + 1, &p); 270 kind = *p++; 271 c = d = strtoi(p, &p); 272 if (*p == ',') 273 d = strtoi(p + 1, &p); 274 if (*p != '\n') 275 errx(2, "error in diff output"); 276 if (kind == 'a') 277 a++; 278 else if (kind == 'c') 279 /* nothing */ ; 280 else if (kind == 'd') 281 c++; 282 else 283 errx(2, "error in diff output"); 284 b++; 285 d++; 286 if (b < a || d < c) 287 errx(2, "error in diff output"); 288 (*dd)[i].old.from = a; 289 (*dd)[i].old.to = b; 290 (*dd)[i].new.from = c; 291 (*dd)[i].new.to = d; 292 if (i > 0) { 293 if ((*dd)[i].old.from < (*dd)[i - 1].old.to || 294 (*dd)[i].new.from < (*dd)[i - 1].new.to) 295 errx(2, "diff output out of order"); 296 } 297 } 298 if (i > 0) { 299 (*dd)[i].old.from = (*dd)[i].old.to = (*dd)[i - 1].old.to; 300 (*dd)[i].new.from = (*dd)[i].new.to = (*dd)[i - 1].new.to; 301 } 302 fclose(f); 303 return (i); 304 } 305 306 static int 307 diffexec(char **diffargv, int fd[]) 308 { 309 posix_spawnattr_t sa; 310 posix_spawn_file_actions_t fa; 311 pid_t pid; 312 int pd, error; 313 314 if ((error = posix_spawnattr_init(&sa)) != 0) 315 errc(2, error, "posix_spawnattr_init"); 316 if ((error = posix_spawn_file_actions_init(&fa)) != 0) 317 errc(2, error, "posix_spawn_file_actions_init"); 318 319 posix_spawnattr_setprocdescp_np(&sa, &pd, 0); 320 posix_spawn_file_actions_adddup2(&fa, fd[1], STDOUT_FILENO); 321 322 error = posix_spawn(&pid, diffargv[0], &fa, &sa, diffargv, environ); 323 if (error != 0) 324 errc(2, error, "could not spawn diff"); 325 326 posix_spawn_file_actions_destroy(&fa); 327 posix_spawnattr_destroy(&sa); 328 close(fd[1]); 329 return (pd); 330 } 331 332 static char * 333 getchange(FILE *b) 334 { 335 char *line; 336 337 while ((line = get_line(b, NULL)) != NULL) { 338 if (isdigit((unsigned char)line[0])) 339 return (line); 340 } 341 return (NULL); 342 } 343 344 345 static char * 346 get_line(FILE *b, size_t *n) 347 { 348 ssize_t len; 349 static char *buf = NULL; 350 static size_t bufsize = 0; 351 352 if ((len = getline(&buf, &bufsize, b)) < 0) 353 return (NULL); 354 355 if (strip_cr && len >= 2 && strcmp("\r\n", &(buf[len - 2])) == 0) { 356 buf[len - 2] = '\n'; 357 buf[len - 1] = '\0'; 358 len--; 359 } 360 361 if (n != NULL) 362 *n = len; 363 364 return (buf); 365 } 366 367 static void 368 merge(int m1, int m2) 369 { 370 struct diff *d1, *d2, *d3; 371 int j, t1, t2; 372 int f1f3delta; 373 bool dup = false; 374 375 d1 = d13; 376 d2 = d23; 377 j = 0; 378 f1f3delta = 0; 379 380 for (;;) { 381 t1 = (d1 < d13 + m1); 382 t2 = (d2 < d23 + m2); 383 if (!t1 && !t2) 384 break; 385 386 /* first file is different from the others */ 387 if (!t2 || (t1 && d1->new.to < d2->new.from)) { 388 /* stuff peculiar to 1st file */ 389 if (eflag == EFLAG_NONE) { 390 separate("1"); 391 change(1, &d1->old, false); 392 keep(2, &d1->new); 393 change(3, &d1->new, false); 394 } else if (mflag) { 395 j++; 396 de[j].type = DIFF_TYPE1; 397 de[j].old = d1->old; 398 de[j].new = d1->new; 399 overlap[j] = 0; 400 } else if (eflag == EFLAG_OVERLAP) { 401 j = edit(d2, dup, j, DIFF_TYPE1); 402 } 403 f1f3delta += (d1->old.to - d1->old.from) - 404 (d1->new.to - d1->new.from); 405 d1++; 406 continue; 407 } 408 /* second file is different from others */ 409 if (!t1 || (t2 && d2->new.to < d1->new.from)) { 410 if (eflag == EFLAG_NONE) { 411 separate("2"); 412 keep(1, &d2->new); 413 change(3, &d2->new, false); 414 change(2, &d2->old, false); 415 } else if (Aflag || mflag) { 416 if (eflag == EFLAG_UNMERGED) { 417 j = edit(d2, dup, j, DIFF_TYPE2); 418 de_delta[j] = f1f3delta; 419 } 420 } 421 d2++; 422 continue; 423 } 424 /* 425 * Merge overlapping changes in first file 426 * this happens after extension (see below). 427 */ 428 if (d1 + 1 < d13 + m1 && d1->new.to >= d1[1].new.from) { 429 d1[1].old.from = d1->old.from; 430 d1[1].new.from = d1->new.from; 431 d1++; 432 continue; 433 } 434 435 /* merge overlapping changes in second */ 436 if (d2 + 1 < d23 + m2 && d2->new.to >= d2[1].new.from) { 437 d2[1].old.from = d2->old.from; 438 d2[1].new.from = d2->new.from; 439 d2++; 440 continue; 441 } 442 /* stuff peculiar to third file or different in all */ 443 if (d1->new.from == d2->new.from && d1->new.to == d2->new.to) { 444 dup = duplicate(&d1->old, &d2->old); 445 /* 446 * dup = 0 means all files differ 447 * dup = 1 means files 1 and 2 identical 448 */ 449 if (eflag == EFLAG_NONE) { 450 separate(dup ? "3" : ""); 451 change(1, &d1->old, dup); 452 change(2, &d2->old, false); 453 d3 = d1->old.to > d1->old.from ? d1 : d2; 454 change(3, &d3->new, false); 455 } else if (mflag) { 456 j++; 457 de[j].type = DIFF_TYPE3; 458 de[j].old = d1->old; 459 de[j].new = d1->new; 460 overlap[j] = !dup; 461 if (!dup) 462 overlapcnt++; 463 } else { 464 j = edit(d1, dup, j, DIFF_TYPE3); 465 } 466 dup = false; 467 f1f3delta += (d1->old.to - d1->old.from) - 468 (d1->new.to - d1->new.from); 469 d1++; 470 d2++; 471 continue; 472 } 473 /* 474 * Overlapping changes from file 1 and 2; extend changes 475 * appropriately to make them coincide. 476 */ 477 if (d1->new.from < d2->new.from) { 478 d2->old.from -= d2->new.from - d1->new.from; 479 d2->new.from = d1->new.from; 480 } else if (d2->new.from < d1->new.from) { 481 d1->old.from -= d1->new.from - d2->new.from; 482 d1->new.from = d2->new.from; 483 } 484 if (d1->new.to > d2->new.to) { 485 d2->old.to += d1->new.to - d2->new.to; 486 d2->new.to = d1->new.to; 487 } else if (d2->new.to > d1->new.to) { 488 d1->old.to += d2->new.to - d1->new.to; 489 d1->new.to = d2->new.to; 490 } 491 } 492 493 if (mflag) 494 mergescript(j, f1f3delta); 495 else if (Aflag) 496 Ascript(j); 497 else if (eflag) 498 edscript(j); 499 } 500 501 static void 502 separate(const char *s) 503 { 504 printf("====%s\n", s); 505 } 506 507 /* 508 * The range of lines rold.from thru rold.to in file i is to be changed. 509 * It is to be printed only if it does not duplicate something to be 510 * printed later. 511 */ 512 static void 513 change(int i, struct range *rold, bool dup) 514 { 515 516 printf("%d:", i); 517 last[i] = rold->to; 518 prange(rold, false); 519 if (dup) 520 return; 521 i--; 522 skip(i, rold->from, NULL); 523 skip(i, rold->to, " "); 524 } 525 526 /* 527 * Print the range of line numbers, rold.from thru rold.to, as n1,n2 or 528 * n1. 529 */ 530 static void 531 prange(struct range *rold, bool delete) 532 { 533 534 if (rold->to <= rold->from) 535 printf("%da\n", rold->from - 1); 536 else { 537 printf("%d", rold->from); 538 if (rold->to > rold->from + 1) 539 printf(",%d", rold->to - 1); 540 if (delete) 541 printf("d\n"); 542 else 543 printf("c\n"); 544 } 545 } 546 547 /* 548 * No difference was reported by diff between file 1 (or 2) and file 3, 549 * and an artificial dummy difference (trange) must be ginned up to 550 * correspond to the change reported in the other file. 551 */ 552 static void 553 keep(int i, struct range *rnew) 554 { 555 int delta; 556 struct range trange; 557 558 delta = last[3] - last[i]; 559 trange.from = rnew->from - delta; 560 trange.to = rnew->to - delta; 561 change(i, &trange, true); 562 } 563 564 /* 565 * skip to just before line number from in file "i". If "pr" is non-NULL, 566 * print all skipped stuff with string pr as a prefix. 567 */ 568 static int 569 skip(int i, int from, const char *pr) 570 { 571 size_t j, n; 572 char *line; 573 574 for (n = 0; cline[i] < from - 1; n += j) { 575 if ((line = get_line(fp[i], &j)) == NULL) 576 errx(2, "logic error"); 577 if (pr != NULL) 578 printf("%s%s", Tflag == 1 ? "\t" : pr, line); 579 cline[i]++; 580 } 581 return ((int) n); 582 } 583 584 /* 585 * Return 1 or 0 according as the old range (in file 1) contains exactly 586 * the same data as the new range (in file 2). 587 */ 588 static bool 589 duplicate(struct range *r1, struct range *r2) 590 { 591 int c, d; 592 int nchar; 593 int nline; 594 595 if (r1->to-r1->from != r2->to-r2->from) 596 return (0); 597 skip(0, r1->from, NULL); 598 skip(1, r2->from, NULL); 599 nchar = 0; 600 for (nline = 0; nline < r1->to - r1->from; nline++) { 601 do { 602 c = getc(fp[0]); 603 d = getc(fp[1]); 604 if (c == -1 && d == -1) 605 break; 606 if (c == -1 || d == -1) 607 errx(2, "logic error"); 608 nchar++; 609 if (c != d) { 610 repos(nchar); 611 return (0); 612 } 613 } while (c != '\n'); 614 } 615 repos(nchar); 616 return (1); 617 } 618 619 static void 620 repos(int nchar) 621 { 622 int i; 623 624 for (i = 0; i < 2; i++) 625 (void)fseek(fp[i], (long)-nchar, SEEK_CUR); 626 } 627 628 /* 629 * collect an editing script for later regurgitation 630 */ 631 static int 632 edit(struct diff *diff, bool dup, int j, enum difftype difftype) 633 { 634 if (!(eflag == EFLAG_UNMERGED || 635 (!dup && eflag == EFLAG_OVERLAP ) || 636 (dup && eflag == EFLAG_NOOVERLAP))) { 637 return (j); 638 } 639 j++; 640 overlap[j] = !dup; 641 if (!dup) 642 overlapcnt++; 643 644 de[j].type = difftype; 645 de[j].old.from = diff->old.from; 646 de[j].old.to = diff->old.to; 647 de[j].new.from = diff->new.from; 648 de[j].new.to = diff->new.to; 649 return (j); 650 } 651 652 static void 653 printrange(FILE *p, struct range *r) 654 { 655 char *line = NULL; 656 size_t len = 0; 657 int i = 1; 658 659 /* We haven't been asked to print anything */ 660 if (r->from == r->to) 661 return; 662 663 if (r->from > r->to) 664 errx(2, "invalid print range"); 665 666 /* 667 * XXX-THJ: We read through all of the file for each range printed. 668 * This duplicates work and will probably impact performance on large 669 * files with lots of ranges. 670 */ 671 fseek(p, 0L, SEEK_SET); 672 while (getline(&line, &len, p) > 0) { 673 if (i >= r->from) 674 printf("%s", line); 675 if (++i > r->to - 1) 676 break; 677 } 678 free(line); 679 } 680 681 /* regurgitate */ 682 static void 683 edscript(int n) 684 { 685 bool delete; 686 struct range *new, *old; 687 688 for (; n > 0; n--) { 689 new = &de[n].new; 690 old = &de[n].old; 691 692 delete = (new->from == new->to); 693 if (de[n].type == DIFF_TYPE1) { 694 if (delete) 695 printf("%dd\n", new->from - 1); 696 else if (old->from == new->from && old->to == new->to) { 697 printf("%dc\n", old->from); 698 printrange(fp[2], old); 699 printf(".\n"); 700 } 701 continue; 702 } else { 703 if (!oflag || !overlap[n]) { 704 prange(old, delete); 705 } else { 706 printf("%da\n", old->to - 1); 707 printf("%s\n", divider); 708 } 709 printrange(fp[2], new); 710 if (!oflag || !overlap[n]) { 711 if (!delete) 712 printf(".\n"); 713 } else { 714 printf("%s %s\n.\n", newmark, f3mark); 715 printf("%da\n%s %s\n.\n", old->from - 1, 716 oldmark, f1mark); 717 } 718 } 719 } 720 if (iflag) 721 printf("w\nq\n"); 722 723 exit(oflag ? overlapcnt > 0 : 0); 724 } 725 726 /* 727 * Output an edit script to turn mine into yours, when there is a conflict 728 * between the 3 files bracket the changes. Regurgitate the diffs in reverse 729 * order to allow the ed script to track down where the lines are as changes 730 * are made. 731 */ 732 static void 733 Ascript(int n) 734 { 735 int startmark; 736 bool deletenew; 737 bool deleteold; 738 739 struct range *new, *old; 740 741 for (; n > 0; n--) { 742 new = &de[n].new; 743 old = &de[n].old; 744 deletenew = (new->from == new->to); 745 deleteold = (old->from == old->to); 746 747 if (de[n].type == DIFF_TYPE2) { 748 if (!oflag || !overlap[n]) { 749 prange(old, deletenew); 750 printrange(fp[2], new); 751 } else { 752 startmark = new->to - 1 + de_delta[n]; 753 754 printf("%da\n", startmark); 755 printf("%s %s\n", newmark, f3mark); 756 757 printf(".\n"); 758 759 printf("%da\n", startmark - 760 (new->to - new->from)); 761 printf("%s %s\n", oldmark, f2mark); 762 if (!deleteold) 763 printrange(fp[1], old); 764 printf("%s\n.\n", divider); 765 } 766 767 } else if (de[n].type == DIFF_TYPE3) { 768 startmark = old->to - 1; 769 770 if (!oflag || !overlap[n]) { 771 prange(old, deletenew); 772 printrange(fp[2], new); 773 } else { 774 printf("%da\n", startmark); 775 printf("%s %s\n", orgmark, f2mark); 776 777 if (deleteold) { 778 struct range r; 779 r.from = old->from-1; 780 r.to = new->to; 781 printrange(fp[1], &r); 782 } else 783 printrange(fp[1], old); 784 785 printf("%s\n", divider); 786 printrange(fp[2], new); 787 } 788 789 if (!oflag || !overlap[n]) { 790 if (!deletenew) 791 printf(".\n"); 792 } else { 793 printf("%s %s\n.\n", newmark, f3mark); 794 795 /* 796 * Go to the start of the conflict in original 797 * file and append lines 798 */ 799 printf("%da\n%s %s\n.\n", 800 startmark - (old->to - old->from), 801 oldmark, f1mark); 802 } 803 } 804 } 805 if (iflag) 806 printf("w\nq\n"); 807 808 exit(overlapcnt > 0); 809 } 810 811 /* 812 * Output the merged file directly (don't generate an ed script). When 813 * regurgitating diffs we need to walk forward through the file and print any 814 * inbetween lines. 815 */ 816 static void 817 mergescript(int i, int f1f3delta) 818 { 819 struct range r, *new, *old; 820 int n; 821 822 r.from = 1; 823 r.to = 1; 824 825 for (n = 1; n <= i; n++) { 826 new = &de[n].new; 827 old = &de[n].old; 828 829 /* 830 * Print any lines leading up to here. If we are merging don't 831 * print deleted ranges. 832 */ 833 if (de[n].type == DIFF_TYPE1) 834 r.to = old->to; 835 else if (de[n].type == DIFF_TYPE2) 836 r.to = new->from + de_delta[n]; 837 else 838 r.to = old->from; 839 840 printrange(fp[0], &r); 841 switch (de[n].type) { 842 case DIFF_TYPE1: 843 /* Content included in "between" printing from fp[0] */ 844 break; 845 case DIFF_TYPE2: 846 printf("%s %s\n", oldmark, f2mark); 847 printrange(fp[1], old); 848 printf("%s\n", divider); 849 printrange(fp[2], new); 850 printf("%s %s\n", newmark, f3mark); 851 break; 852 case DIFF_TYPE3: 853 if (!oflag || !overlap[n]) { 854 printrange(fp[2], new); 855 } else { 856 857 printf("%s %s\n", oldmark, f1mark); 858 printrange(fp[0], old); 859 860 if (eflag != EFLAG_OVERLAP) { 861 printf("%s %s\n", orgmark, f2mark); 862 if (old->from == old->to) { 863 struct range or; 864 or.from = old->from - 1; 865 or.to = new->to; 866 printrange(fp[1], &or); 867 } else { 868 printrange(fp[1], old); 869 } 870 } 871 872 printf("%s\n", divider); 873 874 printrange(fp[2], new); 875 printf("%s %s\n", newmark, f3mark); 876 } 877 break; 878 default: 879 __assert_unreachable(); 880 } 881 882 if (de[n].type == DIFF_TYPE2) 883 r.from = new->to + de_delta[n]; 884 else 885 r.from = old->to; 886 } 887 888 /* 889 * Print from the final range to the end of 'myfile'. Any deletions or 890 * additions to this file should have been handled by now. 891 */ 892 r.from -= f1f3delta; 893 r.to = INT_MAX; 894 printrange(fp[2], &r); 895 exit(overlapcnt > 0); 896 } 897 898 static void 899 increase(void) 900 { 901 struct diff *p; 902 char *q; 903 int *s; 904 size_t newsz, incr; 905 906 /* are the memset(3) calls needed? */ 907 newsz = szchanges == 0 ? 64 : 2 * szchanges; 908 incr = newsz - szchanges; 909 910 p = reallocarray(d13, newsz, sizeof(*p)); 911 if (p == NULL) 912 err(2, NULL); 913 memset(p + szchanges, 0, incr * sizeof(*p)); 914 d13 = p; 915 p = reallocarray(d23, newsz, sizeof(*p)); 916 if (p == NULL) 917 err(2, NULL); 918 memset(p + szchanges, 0, incr * sizeof(*p)); 919 d23 = p; 920 p = reallocarray(de, newsz, sizeof(*p)); 921 if (p == NULL) 922 err(2, NULL); 923 memset(p + szchanges, 0, incr * sizeof(*p)); 924 de = p; 925 q = reallocarray(overlap, newsz, 1); 926 if (q == NULL) 927 err(2, NULL); 928 memset(q + szchanges, 0, incr * 1); 929 overlap = q; 930 s = reallocarray(de_delta, newsz, sizeof(*s)); 931 if (s == NULL) 932 err(2, NULL); 933 memset(s + szchanges, 0, incr * sizeof(*s)); 934 de_delta = s; 935 szchanges = newsz; 936 } 937 938 static void 939 wait_and_check(int pd) 940 { 941 int status; 942 943 while (pdwait(pd, &status, WEXITED, NULL, NULL) == -1) { 944 if (errno != EINTR) 945 err(2, "pdwait"); 946 } 947 close(pd); 948 949 if (WIFEXITED(status) && WEXITSTATUS(status) >= 2) 950 errx(2, "diff exited abnormally"); 951 if (WIFSIGNALED(status)) 952 errx(2, "diff killed by signal %d", WTERMSIG(status)); 953 } 954 955 int 956 main(int argc, char **argv) 957 { 958 int ch, nblabels, m, n; 959 char *labels[] = { NULL, NULL, NULL }; 960 const char *diffprog = DIFF_PATH; 961 char *file1, *file2, *file3; 962 char *diffargv[7]; 963 int diffargc = 0; 964 int fd13[2], fd23[2]; 965 int pd13, pd23; 966 cap_rights_t rights_ro; 967 968 nblabels = 0; 969 eflag = EFLAG_NONE; 970 oflag = 0; 971 diffargv[diffargc++] = __DECONST(char *, diffprog); 972 while ((ch = getopt_long(argc, argv, OPTIONS, longopts, NULL)) != -1) { 973 switch (ch) { 974 case '3': 975 eflag = EFLAG_NOOVERLAP; 976 break; 977 case 'a': 978 diffargv[diffargc++] = __DECONST(char *, "-a"); 979 break; 980 case 'A': 981 Aflag = 1; 982 break; 983 case 'e': 984 eflag = EFLAG_UNMERGED; 985 break; 986 case 'E': 987 eflag = EFLAG_OVERLAP; 988 oflag = 1; 989 break; 990 case 'i': 991 iflag = 1; 992 break; 993 case 'L': 994 oflag = 1; 995 if (nblabels >= 3) 996 errx(2, "too many file label options"); 997 labels[nblabels++] = optarg; 998 break; 999 case 'm': 1000 Aflag = 1; 1001 oflag = 1; 1002 mflag = 1; 1003 break; 1004 case 'T': 1005 Tflag = 1; 1006 break; 1007 case 'x': 1008 eflag = EFLAG_OVERLAP; 1009 break; 1010 case 'X': 1011 oflag = 1; 1012 eflag = EFLAG_OVERLAP; 1013 break; 1014 case DIFFPROG_OPT: 1015 diffargv[0] = optarg; 1016 break; 1017 case STRIPCR_OPT: 1018 strip_cr = 1; 1019 diffargv[diffargc++] = __DECONST(char *, "--strip-trailing-cr"); 1020 break; 1021 case HELP_OPT: 1022 usage(); 1023 exit(0); 1024 case VERSION_OPT: 1025 printf("%s\n", diff3_version); 1026 exit(0); 1027 } 1028 } 1029 argc -= optind; 1030 argv += optind; 1031 1032 if (Aflag) { 1033 if (eflag == EFLAG_NONE) 1034 eflag = EFLAG_UNMERGED; 1035 oflag = 1; 1036 } 1037 1038 if (argc != 3) { 1039 usage(); 1040 exit(2); 1041 } 1042 1043 if (caph_limit_stdio() == -1) 1044 err(2, "unable to limit stdio"); 1045 1046 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK); 1047 1048 /* TODO stdio */ 1049 file1 = argv[0]; 1050 file2 = argv[1]; 1051 file3 = argv[2]; 1052 1053 if (oflag) { 1054 asprintf(&f1mark, "%s", 1055 labels[0] != NULL ? labels[0] : file1); 1056 if (f1mark == NULL) 1057 err(2, "asprintf"); 1058 asprintf(&f2mark, "%s", 1059 labels[1] != NULL ? labels[1] : file2); 1060 if (f2mark == NULL) 1061 err(2, "asprintf"); 1062 asprintf(&f3mark, "%s", 1063 labels[2] != NULL ? labels[2] : file3); 1064 if (f3mark == NULL) 1065 err(2, "asprintf"); 1066 } 1067 fp[0] = fopen(file1, "r"); 1068 if (fp[0] == NULL) 1069 err(2, "Can't open %s", file1); 1070 if (caph_rights_limit(fileno(fp[0]), &rights_ro) < 0) 1071 err(2, "unable to limit rights on: %s", file1); 1072 1073 fp[1] = fopen(file2, "r"); 1074 if (fp[1] == NULL) 1075 err(2, "Can't open %s", file2); 1076 if (caph_rights_limit(fileno(fp[1]), &rights_ro) < 0) 1077 err(2, "unable to limit rights on: %s", file2); 1078 1079 fp[2] = fopen(file3, "r"); 1080 if (fp[2] == NULL) 1081 err(2, "Can't open %s", file3); 1082 if (caph_rights_limit(fileno(fp[2]), &rights_ro) < 0) 1083 err(2, "unable to limit rights on: %s", file3); 1084 1085 if (pipe2(fd13, O_CLOEXEC)) 1086 err(2, "pipe"); 1087 if (pipe2(fd23, O_CLOEXEC)) 1088 err(2, "pipe"); 1089 1090 diffargv[diffargc] = file1; 1091 diffargv[diffargc + 1] = file3; 1092 diffargv[diffargc + 2] = NULL; 1093 pd13 = diffexec(diffargv, fd13); 1094 1095 diffargv[diffargc] = file2; 1096 pd23 = diffexec(diffargv, fd23); 1097 1098 caph_cache_catpages(); 1099 if (caph_enter() < 0) 1100 err(2, "unable to enter capability mode"); 1101 1102 /* parse diffs */ 1103 increase(); 1104 m = readin(fd13[0], &d13); 1105 n = readin(fd23[0], &d23); 1106 1107 wait_and_check(pd13); 1108 wait_and_check(pd23); 1109 1110 merge(m, n); 1111 1112 exit(0); 1113 } 1114