1 /* $OpenBSD: diff3prog.c,v 1.11 2009/10/27 23:59:37 deraadt Exp $ */
2
3 /*
4 * Copyright (C) Caldera International Inc. 2001-2002.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code and documentation must retain the above
11 * copyright notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed or owned by Caldera
18 * International, Inc.
19 * 4. Neither the name of Caldera International, Inc. nor the names of other
20 * contributors may be used to endorse or promote products derived from
21 * this software without specific prior written permission.
22 *
23 * USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
24 * INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
28 * INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
30 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
32 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
33 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36 /*-
37 * Copyright (c) 1991, 1993
38 * The Regents of the University of California. All rights reserved.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 3. Neither the name of the University nor the names of its contributors
49 * may be used to endorse or promote products derived from this software
50 * without specific prior written permission.
51 *
52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62 * SUCH DAMAGE.
63 */
64
65 #include <sys/capsicum.h>
66 #include <sys/procdesc.h>
67 #include <sys/types.h>
68 #include <sys/wait.h>
69
70 #include <capsicum_helpers.h>
71 #include <ctype.h>
72 #include <err.h>
73 #include <getopt.h>
74 #include <stdio.h>
75 #include <stdlib.h>
76 #include <limits.h>
77 #include <inttypes.h>
78 #include <string.h>
79 #include <unistd.h>
80
81 /*
82 * "from" is first in range of changed lines; "to" is last+1
83 * from=to=line after point of insertion for added lines.
84 */
85 struct range {
86 int from;
87 int to;
88 };
89
90 struct diff {
91 #define DIFF_TYPE1 1
92 #define DIFF_TYPE2 2
93 #define DIFF_TYPE3 3
94 int type;
95 #if DEBUG
96 char *line;
97 #endif /* DEBUG */
98
99 /* Ranges as lines */
100 struct range old;
101 struct range new;
102 };
103
104 #define EFLAG_NONE 0
105 #define EFLAG_OVERLAP 1
106 #define EFLAG_NOOVERLAP 2
107 #define EFLAG_UNMERGED 3
108
109 static size_t szchanges;
110
111 static struct diff *d13;
112 static struct diff *d23;
113 /*
114 * "de" is used to gather editing scripts. These are later spewed out in
115 * reverse order. Its first element must be all zero, the "old" and "new"
116 * components of "de" contain line positions. Array overlap indicates which
117 * sections in "de" correspond to lines that are different in all three files.
118 */
119 static struct diff *de;
120 static char *overlap;
121 static int overlapcnt;
122 static FILE *fp[3];
123 static int cline[3]; /* # of the last-read line in each file (0-2) */
124 /*
125 * The latest known correspondence between line numbers of the 3 files
126 * is stored in last[1-3];
127 */
128 static int last[4];
129 static int Aflag, eflag, iflag, mflag, Tflag;
130 static int oflag; /* indicates whether to mark overlaps (-E or -X) */
131 static int strip_cr;
132 static char *f1mark, *f2mark, *f3mark;
133 static const char *oldmark = "<<<<<<<";
134 static const char *orgmark = "|||||||";
135 static const char *newmark = ">>>>>>>";
136 static const char *divider = "=======";
137
138 static bool duplicate(struct range *, struct range *);
139 static int edit(struct diff *, bool, int, int);
140 static char *getchange(FILE *);
141 static char *get_line(FILE *, size_t *);
142 static int readin(int fd, struct diff **);
143 static int skip(int, int, const char *);
144 static void change(int, struct range *, bool);
145 static void keep(int, struct range *);
146 static void merge(int, int);
147 static void prange(struct range *, bool);
148 static void repos(int);
149 static void separate(const char *);
150 static void edscript(int) __dead2;
151 static void Ascript(int) __dead2;
152 static void mergescript(int) __dead2;
153 static void increase(void);
154 static void usage(void);
155 static void printrange(FILE *, struct range *);
156
157 static const char diff3_version[] = "FreeBSD diff3 20240925";
158
159 enum {
160 DIFFPROG_OPT,
161 STRIPCR_OPT,
162 HELP_OPT,
163 VERSION_OPT
164 };
165
166 #define DIFF_PATH "/usr/bin/diff"
167
168 #define OPTIONS "3aAeEiL:mTxX"
169 static struct option longopts[] = {
170 { "ed", no_argument, NULL, 'e' },
171 { "show-overlap", no_argument, NULL, 'E' },
172 { "overlap-only", no_argument, NULL, 'x' },
173 { "initial-tab", no_argument, NULL, 'T' },
174 { "text", no_argument, NULL, 'a' },
175 { "strip-trailing-cr", no_argument, NULL, STRIPCR_OPT },
176 { "show-all", no_argument, NULL, 'A' },
177 { "easy-only", no_argument, NULL, '3' },
178 { "merge", no_argument, NULL, 'm' },
179 { "label", required_argument, NULL, 'L' },
180 { "diff-program", required_argument, NULL, DIFFPROG_OPT },
181 { "help", no_argument, NULL, HELP_OPT},
182 { "version", no_argument, NULL, VERSION_OPT}
183 };
184
185 static void
usage(void)186 usage(void)
187 {
188 fprintf(stderr, "usage: diff3 [-3aAeEimTxX] [-L label1] [-L label2] "
189 "[-L label3] file1 file2 file3\n");
190 }
191
192 static int
strtoi(char * str,char ** end)193 strtoi(char *str, char **end)
194 {
195 intmax_t num;
196
197 errno = 0;
198 num = strtoimax(str, end, 10);
199 if ((end != NULL && *end == str) ||
200 num < 0 || num > INT_MAX ||
201 errno == EINVAL || errno == ERANGE)
202 err(1, "error in diff output");
203 return (int)num;
204 }
205
206 /*
207 * Read diff hunks into the array pointed to by *dd.
208 *
209 * The output from `diff foo bar` consists of a series of hunks describing
210 * an addition (lines in bar not present in foo), change (lines in bar
211 * different from lines in foo), or deletion (lines in foo not present in
212 * bar). Each record starts with a line of the form:
213 *
214 * a[,b]xc[,d]
215 *
216 * where a, b, c, and d are nonnegative integers (b and d are printed only
217 * if they differ from a and c, respectively), and x is either 'a' for an
218 * addition, 'c' for a change, or 'd' for a deletion. This is then
219 * followed by a series of lines (which we ignore) giving the added,
220 * changed, or deleted text.
221 *
222 * For an addition, a == b is the last line in 'foo' before the addition,
223 * while c through d is the range of lines in 'bar' to be added to 'foo'.
224 *
225 * For a change, a through b is the range of lines in 'foo' to be replaced
226 * and c through d is the range of lines in 'bar' to replace them with.
227 *
228 * For a deletion, a through b is the range of lines in 'foo' to remove
229 * and c == d is the line in 'bar' which corresponds to the last line
230 * before the deletion.
231 *
232 * The observant reader will have noticed that x is not really needed and
233 * that we can fully describe any hunk using only a, b, c, and d:
234 *
235 * - an addition replaces a zero-length range in one file with a
236 * non-zero-length range from the other
237 *
238 * - a change replaces a non-zero-length range in one file with a
239 * non-zero-length range from the other
240 *
241 * - a deletion replaces a non-zero-length range in one file with a
242 * zero-length range from the other
243 */
244 static int
readin(int fd,struct diff ** dd)245 readin(int fd, struct diff **dd)
246 {
247 int a, b, c, d;
248 int i;
249 char kind, *p;
250 FILE *f;
251
252 f = fdopen(fd, "r");
253 if (f == NULL)
254 err(2, "fdopen");
255 for (i = 0; (p = getchange(f)) != NULL; i++) {
256 if ((size_t)i >= szchanges - 1)
257 increase();
258 #if DEBUG
259 (*dd)[i].line = strdup(p);
260 #endif /* DEBUG */
261
262 a = b = strtoi(p, &p);
263 if (*p == ',')
264 b = strtoi(p + 1, &p);
265 kind = *p++;
266 c = d = strtoi(p, &p);
267 if (*p == ',')
268 d = strtoi(p + 1, &p);
269 if (*p != '\n')
270 errx(1, "error in diff output");
271 if (kind == 'a')
272 a++;
273 else if (kind == 'c')
274 /* nothing */ ;
275 else if (kind == 'd')
276 c++;
277 else
278 errx(1, "error in diff output");
279 b++;
280 d++;
281 if (b < a || d < c)
282 errx(1, "error in diff output");
283 (*dd)[i].old.from = a;
284 (*dd)[i].old.to = b;
285 (*dd)[i].new.from = c;
286 (*dd)[i].new.to = d;
287 if (i > 0) {
288 if ((*dd)[i].old.from < (*dd)[i - 1].old.to ||
289 (*dd)[i].new.from < (*dd)[i - 1].new.to)
290 errx(1, "diff output out of order");
291 }
292 }
293 if (i > 0) {
294 (*dd)[i].old.from = (*dd)[i].old.to = (*dd)[i - 1].old.to;
295 (*dd)[i].new.from = (*dd)[i].new.to = (*dd)[i - 1].new.to;
296 }
297 fclose(f);
298 return (i);
299 }
300
301 static int
diffexec(const char * diffprog,char ** diffargv,int fd[])302 diffexec(const char *diffprog, char **diffargv, int fd[])
303 {
304 int pd;
305
306 switch (pdfork(&pd, PD_CLOEXEC)) {
307 case 0:
308 close(fd[0]);
309 if (dup2(fd[1], STDOUT_FILENO) == -1)
310 err(2, "child could not duplicate descriptor");
311 close(fd[1]);
312 execvp(diffprog, diffargv);
313 err(2, "could not execute diff: %s", diffprog);
314 break;
315 case -1:
316 err(2, "could not fork");
317 break;
318 }
319 close(fd[1]);
320 return (pd);
321 }
322
323 static char *
getchange(FILE * b)324 getchange(FILE *b)
325 {
326 char *line;
327
328 while ((line = get_line(b, NULL)) != NULL) {
329 if (isdigit((unsigned char)line[0]))
330 return (line);
331 }
332 return (NULL);
333 }
334
335
336 static char *
get_line(FILE * b,size_t * n)337 get_line(FILE *b, size_t *n)
338 {
339 ssize_t len;
340 static char *buf = NULL;
341 static size_t bufsize = 0;
342
343 if ((len = getline(&buf, &bufsize, b)) < 0)
344 return (NULL);
345
346 if (strip_cr && len >= 2 && strcmp("\r\n", &(buf[len - 2])) == 0) {
347 buf[len - 2] = '\n';
348 buf[len - 1] = '\0';
349 len--;
350 }
351
352 if (n != NULL)
353 *n = len;
354
355 return (buf);
356 }
357
358 static void
merge(int m1,int m2)359 merge(int m1, int m2)
360 {
361 struct diff *d1, *d2, *d3;
362 int j, t1, t2;
363 bool dup = false;
364
365 d1 = d13;
366 d2 = d23;
367 j = 0;
368
369 for (;;) {
370 t1 = (d1 < d13 + m1);
371 t2 = (d2 < d23 + m2);
372 if (!t1 && !t2)
373 break;
374
375 /* first file is different from the others */
376 if (!t2 || (t1 && d1->new.to < d2->new.from)) {
377 /* stuff peculiar to 1st file */
378 if (eflag == EFLAG_NONE) {
379 separate("1");
380 change(1, &d1->old, false);
381 keep(2, &d1->new);
382 change(3, &d1->new, false);
383 } else if (eflag == EFLAG_OVERLAP) {
384 j = edit(d2, dup, j, DIFF_TYPE1);
385 }
386 d1++;
387 continue;
388 }
389 /* second file is different from others */
390 if (!t1 || (t2 && d2->new.to < d1->new.from)) {
391 if (eflag == EFLAG_NONE) {
392 separate("2");
393 keep(1, &d2->new);
394 change(3, &d2->new, false);
395 change(2, &d2->old, false);
396 } else if (Aflag || mflag) {
397 // XXX-THJ: What does it mean for the second file to differ?
398 if (eflag == EFLAG_UNMERGED)
399 j = edit(d2, dup, j, DIFF_TYPE2);
400 }
401 d2++;
402 continue;
403 }
404 /*
405 * Merge overlapping changes in first file
406 * this happens after extension (see below).
407 */
408 if (d1 + 1 < d13 + m1 && d1->new.to >= d1[1].new.from) {
409 d1[1].old.from = d1->old.from;
410 d1[1].new.from = d1->new.from;
411 d1++;
412 continue;
413 }
414
415 /* merge overlapping changes in second */
416 if (d2 + 1 < d23 + m2 && d2->new.to >= d2[1].new.from) {
417 d2[1].old.from = d2->old.from;
418 d2[1].new.from = d2->new.from;
419 d2++;
420 continue;
421 }
422 /* stuff peculiar to third file or different in all */
423 if (d1->new.from == d2->new.from && d1->new.to == d2->new.to) {
424 dup = duplicate(&d1->old, &d2->old);
425 /*
426 * dup = 0 means all files differ
427 * dup = 1 means files 1 and 2 identical
428 */
429 if (eflag == EFLAG_NONE) {
430 separate(dup ? "3" : "");
431 change(1, &d1->old, dup);
432 change(2, &d2->old, false);
433 d3 = d1->old.to > d1->old.from ? d1 : d2;
434 change(3, &d3->new, false);
435 } else {
436 j = edit(d1, dup, j, DIFF_TYPE3);
437 }
438 dup = false;
439 d1++;
440 d2++;
441 continue;
442 }
443 /*
444 * Overlapping changes from file 1 and 2; extend changes
445 * appropriately to make them coincide.
446 */
447 if (d1->new.from < d2->new.from) {
448 d2->old.from -= d2->new.from - d1->new.from;
449 d2->new.from = d1->new.from;
450 } else if (d2->new.from < d1->new.from) {
451 d1->old.from -= d1->new.from - d2->new.from;
452 d1->new.from = d2->new.from;
453 }
454 if (d1->new.to > d2->new.to) {
455 d2->old.to += d1->new.to - d2->new.to;
456 d2->new.to = d1->new.to;
457 } else if (d2->new.to > d1->new.to) {
458 d1->old.to += d2->new.to - d1->new.to;
459 d1->new.to = d2->new.to;
460 }
461 }
462
463 if (mflag)
464 mergescript(j);
465 else if (Aflag)
466 Ascript(j);
467 else if (eflag)
468 edscript(j);
469 }
470
471 static void
separate(const char * s)472 separate(const char *s)
473 {
474 printf("====%s\n", s);
475 }
476
477 /*
478 * The range of lines rold.from thru rold.to in file i is to be changed.
479 * It is to be printed only if it does not duplicate something to be
480 * printed later.
481 */
482 static void
change(int i,struct range * rold,bool dup)483 change(int i, struct range *rold, bool dup)
484 {
485
486 printf("%d:", i);
487 last[i] = rold->to;
488 prange(rold, false);
489 if (dup)
490 return;
491 i--;
492 skip(i, rold->from, NULL);
493 skip(i, rold->to, " ");
494 }
495
496 /*
497 * Print the range of line numbers, rold.from thru rold.to, as n1,n2 or
498 * n1.
499 */
500 static void
prange(struct range * rold,bool delete)501 prange(struct range *rold, bool delete)
502 {
503
504 if (rold->to <= rold->from)
505 printf("%da\n", rold->from - 1);
506 else {
507 printf("%d", rold->from);
508 if (rold->to > rold->from + 1)
509 printf(",%d", rold->to - 1);
510 if (delete)
511 printf("d\n");
512 else
513 printf("c\n");
514 }
515 }
516
517 /*
518 * No difference was reported by diff between file 1 (or 2) and file 3,
519 * and an artificial dummy difference (trange) must be ginned up to
520 * correspond to the change reported in the other file.
521 */
522 static void
keep(int i,struct range * rnew)523 keep(int i, struct range *rnew)
524 {
525 int delta;
526 struct range trange;
527
528 delta = last[3] - last[i];
529 trange.from = rnew->from - delta;
530 trange.to = rnew->to - delta;
531 change(i, &trange, true);
532 }
533
534 /*
535 * skip to just before line number from in file "i". If "pr" is non-NULL,
536 * print all skipped stuff with string pr as a prefix.
537 */
538 static int
skip(int i,int from,const char * pr)539 skip(int i, int from, const char *pr)
540 {
541 size_t j, n;
542 char *line;
543
544 for (n = 0; cline[i] < from - 1; n += j) {
545 if ((line = get_line(fp[i], &j)) == NULL)
546 errx(EXIT_FAILURE, "logic error");
547 if (pr != NULL)
548 printf("%s%s", Tflag == 1 ? "\t" : pr, line);
549 cline[i]++;
550 }
551 return ((int) n);
552 }
553
554 /*
555 * Return 1 or 0 according as the old range (in file 1) contains exactly
556 * the same data as the new range (in file 2).
557 */
558 static bool
duplicate(struct range * r1,struct range * r2)559 duplicate(struct range *r1, struct range *r2)
560 {
561 int c, d;
562 int nchar;
563 int nline;
564
565 if (r1->to-r1->from != r2->to-r2->from)
566 return (0);
567 skip(0, r1->from, NULL);
568 skip(1, r2->from, NULL);
569 nchar = 0;
570 for (nline = 0; nline < r1->to - r1->from; nline++) {
571 do {
572 c = getc(fp[0]);
573 d = getc(fp[1]);
574 if (c == -1 && d == -1)
575 break;
576 if (c == -1 || d == -1)
577 errx(EXIT_FAILURE, "logic error");
578 nchar++;
579 if (c != d) {
580 repos(nchar);
581 return (0);
582 }
583 } while (c != '\n');
584 }
585 repos(nchar);
586 return (1);
587 }
588
589 static void
repos(int nchar)590 repos(int nchar)
591 {
592 int i;
593
594 for (i = 0; i < 2; i++)
595 (void)fseek(fp[i], (long)-nchar, SEEK_CUR);
596 }
597
598 /*
599 * collect an editing script for later regurgitation
600 */
601 static int
edit(struct diff * diff,bool dup,int j,int difftype)602 edit(struct diff *diff, bool dup, int j, int difftype)
603 {
604 if (!(eflag == EFLAG_UNMERGED ||
605 (!dup && eflag == EFLAG_OVERLAP ) ||
606 (dup && eflag == EFLAG_NOOVERLAP))) {
607 return (j);
608 }
609 j++;
610 overlap[j] = !dup;
611 if (!dup)
612 overlapcnt++;
613
614 de[j].type = difftype;
615 #if DEBUG
616 de[j].line = strdup(diff->line);
617 #endif /* DEBUG */
618
619 de[j].old.from = diff->old.from;
620 de[j].old.to = diff->old.to;
621 de[j].new.from = diff->new.from;
622 de[j].new.to = diff->new.to;
623 return (j);
624 }
625
626 static void
printrange(FILE * p,struct range * r)627 printrange(FILE *p, struct range *r)
628 {
629 char *line = NULL;
630 size_t len = 0;
631 int i = 1;
632
633 /* We haven't been asked to print anything */
634 if (r->from == r->to)
635 return;
636
637 if (r->from > r->to)
638 errx(EXIT_FAILURE, "invalid print range");
639
640 /*
641 * XXX-THJ: We read through all of the file for each range printed.
642 * This duplicates work and will probably impact performance on large
643 * files with lots of ranges.
644 */
645 fseek(p, 0L, SEEK_SET);
646 while (getline(&line, &len, p) > 0) {
647 if (i >= r->from)
648 printf("%s", line);
649 if (++i > r->to - 1)
650 break;
651 }
652 free(line);
653 }
654
655 /* regurgitate */
656 static void
edscript(int n)657 edscript(int n)
658 {
659 bool delete;
660 struct range *new, *old;
661
662 for (; n > 0; n--) {
663 new = &de[n].new;
664 old = &de[n].old;
665
666 delete = (new->from == new->to);
667 if (de[n].type == DIFF_TYPE1) {
668 if (delete)
669 printf("%dd\n", new->from - 1);
670 else if (old->from == new->from && old->to == new->to) {
671 printf("%dc\n", old->from);
672 printrange(fp[2], old);
673 printf(".\n");
674 }
675 continue;
676 } else {
677 if (!oflag || !overlap[n]) {
678 prange(old, delete);
679 } else {
680 printf("%da\n", old->to - 1);
681 printf("%s\n", divider);
682 }
683 printrange(fp[2], new);
684 if (!oflag || !overlap[n]) {
685 if (!delete)
686 printf(".\n");
687 } else {
688 printf("%s %s\n.\n", newmark, f3mark);
689 printf("%da\n%s %s\n.\n", old->from - 1,
690 oldmark, f1mark);
691 }
692 }
693 }
694 if (iflag)
695 printf("w\nq\n");
696
697 exit(eflag == EFLAG_NONE ? overlapcnt : 0);
698 }
699
700 /*
701 * Output an edit script to turn mine into yours, when there is a conflict
702 * between the 3 files bracket the changes. Regurgitate the diffs in reverse
703 * order to allow the ed script to track down where the lines are as changes
704 * are made.
705 */
706 static void
Ascript(int n)707 Ascript(int n)
708 {
709 int startmark;
710 bool deletenew;
711 bool deleteold;
712
713 struct range *new, *old;
714
715 for (; n > 0; n--) {
716 new = &de[n].new;
717 old = &de[n].old;
718 deletenew = (new->from == new->to);
719 deleteold = (old->from == old->to);
720
721 if (de[n].type == DIFF_TYPE2) {
722 if (!oflag || !overlap[n]) {
723 prange(old, deletenew);
724 printrange(fp[2], new);
725 } else {
726 startmark = new->to - 1;
727
728 printf("%da\n", startmark);
729 printf("%s %s\n", newmark, f3mark);
730
731 printf(".\n");
732
733 printf("%da\n", startmark -
734 (new->to - new->from));
735 printf("%s %s\n", oldmark, f2mark);
736 if (!deleteold)
737 printrange(fp[1], old);
738 printf("%s\n.\n", divider);
739 }
740
741 } else if (de[n].type == DIFF_TYPE3) {
742 startmark = old->to - 1;
743
744 if (!oflag || !overlap[n]) {
745 prange(old, deletenew);
746 printrange(fp[2], new);
747 } else {
748 printf("%da\n", startmark);
749 printf("%s %s\n", orgmark, f2mark);
750
751 if (deleteold) {
752 struct range r;
753 r.from = old->from-1;
754 r.to = new->to;
755 printrange(fp[1], &r);
756 } else
757 printrange(fp[1], old);
758
759 printf("%s\n", divider);
760 printrange(fp[2], new);
761 }
762
763 if (!oflag || !overlap[n]) {
764 if (!deletenew)
765 printf(".\n");
766 } else {
767 printf("%s %s\n.\n", newmark, f3mark);
768
769 /*
770 * Go to the start of the conflict in original
771 * file and append lines
772 */
773 printf("%da\n%s %s\n.\n",
774 startmark - (old->to - old->from),
775 oldmark, f1mark);
776 }
777 }
778 }
779 if (iflag)
780 printf("w\nq\n");
781
782 exit(overlapcnt > 0);
783 }
784
785 /*
786 * Output the merged file directly (don't generate an ed script). When
787 * regurgitating diffs we need to walk forward through the file and print any
788 * inbetween lines.
789 */
790 static void
mergescript(int i)791 mergescript(int i)
792 {
793 struct range r, *new, *old;
794 int n;
795 bool delete = false;
796
797 r.from = 1;
798 r.to = 1;
799
800 for (n = 1; n <= i; n++) {
801 new = &de[n].new;
802 old = &de[n].old;
803
804 /*
805 * Print any lines leading up to here. If we are merging don't
806 * print deleted ranges.
807 */
808 delete = (new->from == new->to);
809 if (de[n].type == DIFF_TYPE1 && delete)
810 r.to = new->from - 1;
811 else if (de[n].type == DIFF_TYPE3 && (old->from == old->to)) {
812 r.from = old->from - 1;
813 r.to = new->from;
814 } else
815 r.to = old->from;
816
817 printrange(fp[0], &r);
818 switch (de[n].type) {
819 case DIFF_TYPE1:
820 /* If this isn't a delete print it */
821 if (!delete)
822 printrange(fp[2], new);
823 break;
824 case DIFF_TYPE2:
825 printf("%s %s\n", oldmark, f2mark);
826 printrange(fp[1], old);
827 printf("%s\n", divider);
828 printrange(fp[2], new);
829 printf("%s %s\n", newmark, f3mark);
830 break;
831 case DIFF_TYPE3:
832 if (!oflag || !overlap[n]) {
833 printrange(fp[2], new);
834 } else {
835
836 printf("%s %s\n", oldmark, f1mark);
837 printrange(fp[0], old);
838
839 if (eflag != EFLAG_OVERLAP) {
840 printf("%s %s\n", orgmark, f2mark);
841 if (old->from == old->to) {
842 struct range or;
843 or.from = old->from - 1;
844 or.to = new->to;
845 printrange(fp[1], &or);
846 } else {
847 printrange(fp[1], old);
848 }
849 }
850
851 printf("%s\n", divider);
852
853 printrange(fp[2], new);
854 printf("%s %s\n", newmark, f3mark);
855 }
856 break;
857 default:
858 printf("Error: Unhandled diff type - exiting\n");
859 exit(EXIT_FAILURE);
860 }
861
862 if (old->from == old->to)
863 r.from = new->to;
864 else
865 r.from = old->to;
866 }
867
868 /*
869 * Print from the final range to the end of 'myfile'. Any deletions or
870 * additions to this file should have been handled by now.
871 *
872 * If the ranges are the same we need to rewind a line.
873 * If the new range is 0 length (from == to), we need to use the old
874 * range.
875 */
876 new = &de[n-1].new;
877 old = &de[n-1].old;
878
879 if (old->from == new->from && old->to == new->to)
880 r.from--;
881 else if (new->from == new->to)
882 r.from = old->from;
883
884 r.to = INT_MAX;
885 printrange(fp[2], &r);
886 exit(overlapcnt > 0);
887 }
888
889 static void
increase(void)890 increase(void)
891 {
892 struct diff *p;
893 char *q;
894 size_t newsz, incr;
895
896 /* are the memset(3) calls needed? */
897 newsz = szchanges == 0 ? 64 : 2 * szchanges;
898 incr = newsz - szchanges;
899
900 p = reallocarray(d13, newsz, sizeof(*p));
901 if (p == NULL)
902 err(1, NULL);
903 memset(p + szchanges, 0, incr * sizeof(*p));
904 d13 = p;
905 p = reallocarray(d23, newsz, sizeof(*p));
906 if (p == NULL)
907 err(1, NULL);
908 memset(p + szchanges, 0, incr * sizeof(*p));
909 d23 = p;
910 p = reallocarray(de, newsz, sizeof(*p));
911 if (p == NULL)
912 err(1, NULL);
913 memset(p + szchanges, 0, incr * sizeof(*p));
914 de = p;
915 q = reallocarray(overlap, newsz, 1);
916 if (q == NULL)
917 err(1, NULL);
918 memset(q + szchanges, 0, incr * 1);
919 overlap = q;
920 szchanges = newsz;
921 }
922
923 static void
wait_and_check(int pd)924 wait_and_check(int pd)
925 {
926 int status;
927
928 while (pdwait(pd, &status, WEXITED, NULL, NULL) == -1) {
929 if (errno != EINTR)
930 err(2, "pdwait");
931 }
932
933 if (WIFEXITED(status) && WEXITSTATUS(status) >= 2)
934 errx(2, "diff exited abnormally");
935 if (WIFSIGNALED(status))
936 errx(2, "diff killed by signal %d", WTERMSIG(status));
937 }
938
939 int
main(int argc,char ** argv)940 main(int argc, char **argv)
941 {
942 int ch, nblabels, m, n;
943 char *labels[] = { NULL, NULL, NULL };
944 const char *diffprog = DIFF_PATH;
945 char *file1, *file2, *file3;
946 char *diffargv[7];
947 int diffargc = 0;
948 int fd13[2], fd23[2];
949 int pd13, pd23;
950 cap_rights_t rights_ro;
951
952 nblabels = 0;
953 eflag = EFLAG_NONE;
954 oflag = 0;
955 diffargv[diffargc++] = __DECONST(char *, diffprog);
956 while ((ch = getopt_long(argc, argv, OPTIONS, longopts, NULL)) != -1) {
957 switch (ch) {
958 case '3':
959 eflag = EFLAG_NOOVERLAP;
960 break;
961 case 'a':
962 diffargv[diffargc++] = __DECONST(char *, "-a");
963 break;
964 case 'A':
965 Aflag = 1;
966 break;
967 case 'e':
968 eflag = EFLAG_UNMERGED;
969 break;
970 case 'E':
971 eflag = EFLAG_OVERLAP;
972 oflag = 1;
973 break;
974 case 'i':
975 iflag = 1;
976 break;
977 case 'L':
978 oflag = 1;
979 if (nblabels >= 3)
980 errx(2, "too many file label options");
981 labels[nblabels++] = optarg;
982 break;
983 case 'm':
984 Aflag = 1;
985 oflag = 1;
986 mflag = 1;
987 break;
988 case 'T':
989 Tflag = 1;
990 break;
991 case 'x':
992 eflag = EFLAG_OVERLAP;
993 break;
994 case 'X':
995 oflag = 1;
996 eflag = EFLAG_OVERLAP;
997 break;
998 case DIFFPROG_OPT:
999 diffprog = optarg;
1000 break;
1001 case STRIPCR_OPT:
1002 strip_cr = 1;
1003 diffargv[diffargc++] = __DECONST(char *, "--strip-trailing-cr");
1004 break;
1005 case HELP_OPT:
1006 usage();
1007 exit(0);
1008 case VERSION_OPT:
1009 printf("%s\n", diff3_version);
1010 exit(0);
1011 }
1012 }
1013 argc -= optind;
1014 argv += optind;
1015
1016 if (Aflag) {
1017 if (eflag == EFLAG_NONE)
1018 eflag = EFLAG_UNMERGED;
1019 oflag = 1;
1020 }
1021
1022 if (argc != 3) {
1023 usage();
1024 exit(2);
1025 }
1026
1027 if (caph_limit_stdio() == -1)
1028 err(2, "unable to limit stdio");
1029
1030 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK);
1031
1032 /* TODO stdio */
1033 file1 = argv[0];
1034 file2 = argv[1];
1035 file3 = argv[2];
1036
1037 if (oflag) {
1038 asprintf(&f1mark, "%s",
1039 labels[0] != NULL ? labels[0] : file1);
1040 if (f1mark == NULL)
1041 err(2, "asprintf");
1042 asprintf(&f2mark, "%s",
1043 labels[1] != NULL ? labels[1] : file2);
1044 if (f2mark == NULL)
1045 err(2, "asprintf");
1046 asprintf(&f3mark, "%s",
1047 labels[2] != NULL ? labels[2] : file3);
1048 if (f3mark == NULL)
1049 err(2, "asprintf");
1050 }
1051 fp[0] = fopen(file1, "r");
1052 if (fp[0] == NULL)
1053 err(2, "Can't open %s", file1);
1054 if (caph_rights_limit(fileno(fp[0]), &rights_ro) < 0)
1055 err(2, "unable to limit rights on: %s", file1);
1056
1057 fp[1] = fopen(file2, "r");
1058 if (fp[1] == NULL)
1059 err(2, "Can't open %s", file2);
1060 if (caph_rights_limit(fileno(fp[1]), &rights_ro) < 0)
1061 err(2, "unable to limit rights on: %s", file2);
1062
1063 fp[2] = fopen(file3, "r");
1064 if (fp[2] == NULL)
1065 err(2, "Can't open %s", file3);
1066 if (caph_rights_limit(fileno(fp[2]), &rights_ro) < 0)
1067 err(2, "unable to limit rights on: %s", file3);
1068
1069 if (pipe(fd13))
1070 err(2, "pipe");
1071 if (pipe(fd23))
1072 err(2, "pipe");
1073
1074 diffargv[diffargc] = file1;
1075 diffargv[diffargc + 1] = file3;
1076 diffargv[diffargc + 2] = NULL;
1077 pd13 = diffexec(diffprog, diffargv, fd13);
1078
1079 diffargv[diffargc] = file2;
1080 pd23 = diffexec(diffprog, diffargv, fd23);
1081
1082 caph_cache_catpages();
1083 if (caph_enter() < 0)
1084 err(2, "unable to enter capability mode");
1085
1086 /* parse diffs */
1087 increase();
1088 m = readin(fd13[0], &d13);
1089 n = readin(fd23[0], &d23);
1090
1091 wait_and_check(pd13);
1092 wait_and_check(pd23);
1093
1094 merge(m, n);
1095
1096 return (EXIT_SUCCESS);
1097 }
1098