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/event.h>
69 #include <sys/wait.h>
70
71 #include <capsicum_helpers.h>
72 #include <ctype.h>
73 #include <err.h>
74 #include <getopt.h>
75 #include <stdio.h>
76 #include <stdlib.h>
77 #include <limits.h>
78 #include <inttypes.h>
79 #include <string.h>
80 #include <unistd.h>
81
82 /*
83 * "from" is first in range of changed lines; "to" is last+1
84 * from=to=line after point of insertion for added lines.
85 */
86 struct range {
87 int from;
88 int to;
89 };
90
91 struct diff {
92 #define DIFF_TYPE1 1
93 #define DIFF_TYPE2 2
94 #define DIFF_TYPE3 3
95 int type;
96 #if DEBUG
97 char *line;
98 #endif /* DEBUG */
99
100 /* Ranges as lines */
101 struct range old;
102 struct range new;
103 };
104
105 #define EFLAG_NONE 0
106 #define EFLAG_OVERLAP 1
107 #define EFLAG_NOOVERLAP 2
108 #define EFLAG_UNMERGED 3
109
110 static size_t szchanges;
111
112 static struct diff *d13;
113 static struct diff *d23;
114 /*
115 * "de" is used to gather editing scripts. These are later spewed out in
116 * reverse order. Its first element must be all zero, the "old" and "new"
117 * components of "de" contain line positions. Array overlap indicates which
118 * sections in "de" correspond to lines that are different in all three files.
119 */
120 static struct diff *de;
121 static char *overlap;
122 static int overlapcnt;
123 static FILE *fp[3];
124 static int cline[3]; /* # of the last-read line in each file (0-2) */
125 /*
126 * The latest known correspondence between line numbers of the 3 files
127 * is stored in last[1-3];
128 */
129 static int last[4];
130 static int Aflag, eflag, iflag, mflag, Tflag;
131 static int oflag; /* indicates whether to mark overlaps (-E or -X) */
132 static int strip_cr;
133 static char *f1mark, *f2mark, *f3mark;
134 static const char *oldmark = "<<<<<<<";
135 static const char *orgmark = "|||||||";
136 static const char *newmark = ">>>>>>>";
137 static const char *divider = "=======";
138
139 static bool duplicate(struct range *, struct range *);
140 static int edit(struct diff *, bool, int, int);
141 static char *getchange(FILE *);
142 static char *get_line(FILE *, size_t *);
143 static int readin(int fd, struct diff **);
144 static int skip(int, int, const char *);
145 static void change(int, struct range *, bool);
146 static void keep(int, struct range *);
147 static void merge(int, int);
148 static void prange(struct range *, bool);
149 static void repos(int);
150 static void separate(const char *);
151 static void edscript(int) __dead2;
152 static void Ascript(int) __dead2;
153 static void mergescript(int) __dead2;
154 static void increase(void);
155 static void usage(void);
156 static void printrange(FILE *, struct range *);
157
158 static const char diff3_version[] = "FreeBSD diff3 20240925";
159
160 enum {
161 DIFFPROG_OPT,
162 STRIPCR_OPT,
163 HELP_OPT,
164 VERSION_OPT
165 };
166
167 #define DIFF_PATH "/usr/bin/diff"
168
169 #define OPTIONS "3aAeEiL:mTxX"
170 static struct option longopts[] = {
171 { "ed", no_argument, NULL, 'e' },
172 { "show-overlap", no_argument, NULL, 'E' },
173 { "overlap-only", no_argument, NULL, 'x' },
174 { "initial-tab", no_argument, NULL, 'T' },
175 { "text", no_argument, NULL, 'a' },
176 { "strip-trailing-cr", no_argument, NULL, STRIPCR_OPT },
177 { "show-all", no_argument, NULL, 'A' },
178 { "easy-only", no_argument, NULL, '3' },
179 { "merge", no_argument, NULL, 'm' },
180 { "label", required_argument, NULL, 'L' },
181 { "diff-program", required_argument, NULL, DIFFPROG_OPT },
182 { "help", no_argument, NULL, HELP_OPT},
183 { "version", no_argument, NULL, VERSION_OPT}
184 };
185
186 static void
usage(void)187 usage(void)
188 {
189 fprintf(stderr, "usage: diff3 [-3aAeEimTxX] [-L label1] [-L label2] "
190 "[-L label3] file1 file2 file3\n");
191 }
192
193 static int
strtoi(char * str,char ** end)194 strtoi(char *str, char **end)
195 {
196 intmax_t num;
197
198 errno = 0;
199 num = strtoimax(str, end, 10);
200 if ((end != NULL && *end == str) ||
201 num < 0 || num > INT_MAX ||
202 errno == EINVAL || errno == ERANGE)
203 err(1, "error in diff output");
204 return (int)num;
205 }
206
207 /*
208 * Read diff hunks into the array pointed to by *dd.
209 *
210 * The output from `diff foo bar` consists of a series of hunks describing
211 * an addition (lines in bar not present in foo), change (lines in bar
212 * different from lines in foo), or deletion (lines in foo not present in
213 * bar). Each record starts with a line of the form:
214 *
215 * a[,b]xc[,d]
216 *
217 * where a, b, c, and d are nonnegative integers (b and d are printed only
218 * if they differ from a and c, respectively), and x is either 'a' for an
219 * addition, 'c' for a change, or 'd' for a deletion. This is then
220 * followed by a series of lines (which we ignore) giving the added,
221 * changed, or deleted text.
222 *
223 * For an addition, a == b is the last line in 'foo' before the addition,
224 * while c through d is the range of lines in 'bar' to be added to 'foo'.
225 *
226 * For a change, a through b is the range of lines in 'foo' to be replaced
227 * and c through d is the range of lines in 'bar' to replace them with.
228 *
229 * For a deletion, a through b is the range of lines in 'foo' to remove
230 * and c == d is the line in 'bar' which corresponds to the last line
231 * before the deletion.
232 *
233 * The observant reader will have noticed that x is not really needed and
234 * that we can fully describe any hunk using only a, b, c, and d:
235 *
236 * - an addition replaces a zero-length range in one file with a
237 * non-zero-length range from the other
238 *
239 * - a change replaces a non-zero-length range in one file with a
240 * non-zero-length range from the other
241 *
242 * - a deletion replaces a non-zero-length range in one file with a
243 * zero-length range from the other
244 */
245 static int
readin(int fd,struct diff ** dd)246 readin(int fd, struct diff **dd)
247 {
248 int a, b, c, d;
249 int i;
250 char kind, *p;
251 FILE *f;
252
253 f = fdopen(fd, "r");
254 if (f == NULL)
255 err(2, "fdopen");
256 for (i = 0; (p = getchange(f)) != NULL; i++) {
257 if ((size_t)i >= szchanges - 1)
258 increase();
259 #if DEBUG
260 (*dd)[i].line = strdup(p);
261 #endif /* DEBUG */
262
263 a = b = strtoi(p, &p);
264 if (*p == ',')
265 b = strtoi(p + 1, &p);
266 kind = *p++;
267 c = d = strtoi(p, &p);
268 if (*p == ',')
269 d = strtoi(p + 1, &p);
270 if (*p != '\n')
271 errx(1, "error in diff output");
272 if (kind == 'a')
273 a++;
274 else if (kind == 'c')
275 /* nothing */ ;
276 else if (kind == 'd')
277 c++;
278 else
279 errx(1, "error in diff output");
280 b++;
281 d++;
282 if (b < a || d < c)
283 errx(1, "error in diff output");
284 (*dd)[i].old.from = a;
285 (*dd)[i].old.to = b;
286 (*dd)[i].new.from = c;
287 (*dd)[i].new.to = d;
288 if (i > 0) {
289 if ((*dd)[i].old.from < (*dd)[i - 1].old.to ||
290 (*dd)[i].new.from < (*dd)[i - 1].new.to)
291 errx(1, "diff output out of order");
292 }
293 }
294 if (i > 0) {
295 (*dd)[i].old.from = (*dd)[i].old.to = (*dd)[i - 1].old.to;
296 (*dd)[i].new.from = (*dd)[i].new.to = (*dd)[i - 1].new.to;
297 }
298 fclose(f);
299 return (i);
300 }
301
302 static int
diffexec(const char * diffprog,char ** diffargv,int fd[])303 diffexec(const char *diffprog, char **diffargv, int fd[])
304 {
305 int pd;
306
307 switch (pdfork(&pd, PD_CLOEXEC)) {
308 case 0:
309 close(fd[0]);
310 if (dup2(fd[1], STDOUT_FILENO) == -1)
311 err(2, "child could not duplicate descriptor");
312 close(fd[1]);
313 execvp(diffprog, diffargv);
314 err(2, "could not execute diff: %s", diffprog);
315 break;
316 case -1:
317 err(2, "could not fork");
318 break;
319 }
320 close(fd[1]);
321 return (pd);
322 }
323
324 static char *
getchange(FILE * b)325 getchange(FILE *b)
326 {
327 char *line;
328
329 while ((line = get_line(b, NULL)) != NULL) {
330 if (isdigit((unsigned char)line[0]))
331 return (line);
332 }
333 return (NULL);
334 }
335
336
337 static char *
get_line(FILE * b,size_t * n)338 get_line(FILE *b, size_t *n)
339 {
340 ssize_t len;
341 static char *buf = NULL;
342 static size_t bufsize = 0;
343
344 if ((len = getline(&buf, &bufsize, b)) < 0)
345 return (NULL);
346
347 if (strip_cr && len >= 2 && strcmp("\r\n", &(buf[len - 2])) == 0) {
348 buf[len - 2] = '\n';
349 buf[len - 1] = '\0';
350 len--;
351 }
352
353 if (n != NULL)
354 *n = len;
355
356 return (buf);
357 }
358
359 static void
merge(int m1,int m2)360 merge(int m1, int m2)
361 {
362 struct diff *d1, *d2, *d3;
363 int j, t1, t2;
364 bool dup = false;
365
366 d1 = d13;
367 d2 = d23;
368 j = 0;
369
370 for (;;) {
371 t1 = (d1 < d13 + m1);
372 t2 = (d2 < d23 + m2);
373 if (!t1 && !t2)
374 break;
375
376 /* first file is different from the others */
377 if (!t2 || (t1 && d1->new.to < d2->new.from)) {
378 /* stuff peculiar to 1st file */
379 if (eflag == EFLAG_NONE) {
380 separate("1");
381 change(1, &d1->old, false);
382 keep(2, &d1->new);
383 change(3, &d1->new, false);
384 } else if (eflag == EFLAG_OVERLAP) {
385 j = edit(d2, dup, j, DIFF_TYPE1);
386 }
387 d1++;
388 continue;
389 }
390 /* second file is different from others */
391 if (!t1 || (t2 && d2->new.to < d1->new.from)) {
392 if (eflag == EFLAG_NONE) {
393 separate("2");
394 keep(1, &d2->new);
395 change(3, &d2->new, false);
396 change(2, &d2->old, false);
397 } else if (Aflag || mflag) {
398 // XXX-THJ: What does it mean for the second file to differ?
399 if (eflag == EFLAG_UNMERGED)
400 j = edit(d2, dup, j, DIFF_TYPE2);
401 }
402 d2++;
403 continue;
404 }
405 /*
406 * Merge overlapping changes in first file
407 * this happens after extension (see below).
408 */
409 if (d1 + 1 < d13 + m1 && d1->new.to >= d1[1].new.from) {
410 d1[1].old.from = d1->old.from;
411 d1[1].new.from = d1->new.from;
412 d1++;
413 continue;
414 }
415
416 /* merge overlapping changes in second */
417 if (d2 + 1 < d23 + m2 && d2->new.to >= d2[1].new.from) {
418 d2[1].old.from = d2->old.from;
419 d2[1].new.from = d2->new.from;
420 d2++;
421 continue;
422 }
423 /* stuff peculiar to third file or different in all */
424 if (d1->new.from == d2->new.from && d1->new.to == d2->new.to) {
425 dup = duplicate(&d1->old, &d2->old);
426 /*
427 * dup = 0 means all files differ
428 * dup = 1 means files 1 and 2 identical
429 */
430 if (eflag == EFLAG_NONE) {
431 separate(dup ? "3" : "");
432 change(1, &d1->old, dup);
433 change(2, &d2->old, false);
434 d3 = d1->old.to > d1->old.from ? d1 : d2;
435 change(3, &d3->new, false);
436 } else {
437 j = edit(d1, dup, j, DIFF_TYPE3);
438 }
439 dup = false;
440 d1++;
441 d2++;
442 continue;
443 }
444 /*
445 * Overlapping changes from file 1 and 2; extend changes
446 * appropriately to make them coincide.
447 */
448 if (d1->new.from < d2->new.from) {
449 d2->old.from -= d2->new.from - d1->new.from;
450 d2->new.from = d1->new.from;
451 } else if (d2->new.from < d1->new.from) {
452 d1->old.from -= d1->new.from - d2->new.from;
453 d1->new.from = d2->new.from;
454 }
455 if (d1->new.to > d2->new.to) {
456 d2->old.to += d1->new.to - d2->new.to;
457 d2->new.to = d1->new.to;
458 } else if (d2->new.to > d1->new.to) {
459 d1->old.to += d2->new.to - d1->new.to;
460 d1->new.to = d2->new.to;
461 }
462 }
463
464 if (mflag)
465 mergescript(j);
466 else if (Aflag)
467 Ascript(j);
468 else if (eflag)
469 edscript(j);
470 }
471
472 static void
separate(const char * s)473 separate(const char *s)
474 {
475 printf("====%s\n", s);
476 }
477
478 /*
479 * The range of lines rold.from thru rold.to in file i is to be changed.
480 * It is to be printed only if it does not duplicate something to be
481 * printed later.
482 */
483 static void
change(int i,struct range * rold,bool dup)484 change(int i, struct range *rold, bool dup)
485 {
486
487 printf("%d:", i);
488 last[i] = rold->to;
489 prange(rold, false);
490 if (dup)
491 return;
492 i--;
493 skip(i, rold->from, NULL);
494 skip(i, rold->to, " ");
495 }
496
497 /*
498 * Print the range of line numbers, rold.from thru rold.to, as n1,n2 or
499 * n1.
500 */
501 static void
prange(struct range * rold,bool delete)502 prange(struct range *rold, bool delete)
503 {
504
505 if (rold->to <= rold->from)
506 printf("%da\n", rold->from - 1);
507 else {
508 printf("%d", rold->from);
509 if (rold->to > rold->from + 1)
510 printf(",%d", rold->to - 1);
511 if (delete)
512 printf("d\n");
513 else
514 printf("c\n");
515 }
516 }
517
518 /*
519 * No difference was reported by diff between file 1 (or 2) and file 3,
520 * and an artificial dummy difference (trange) must be ginned up to
521 * correspond to the change reported in the other file.
522 */
523 static void
keep(int i,struct range * rnew)524 keep(int i, struct range *rnew)
525 {
526 int delta;
527 struct range trange;
528
529 delta = last[3] - last[i];
530 trange.from = rnew->from - delta;
531 trange.to = rnew->to - delta;
532 change(i, &trange, true);
533 }
534
535 /*
536 * skip to just before line number from in file "i". If "pr" is non-NULL,
537 * print all skipped stuff with string pr as a prefix.
538 */
539 static int
skip(int i,int from,const char * pr)540 skip(int i, int from, const char *pr)
541 {
542 size_t j, n;
543 char *line;
544
545 for (n = 0; cline[i] < from - 1; n += j) {
546 if ((line = get_line(fp[i], &j)) == NULL)
547 errx(EXIT_FAILURE, "logic error");
548 if (pr != NULL)
549 printf("%s%s", Tflag == 1 ? "\t" : pr, line);
550 cline[i]++;
551 }
552 return ((int) n);
553 }
554
555 /*
556 * Return 1 or 0 according as the old range (in file 1) contains exactly
557 * the same data as the new range (in file 2).
558 */
559 static bool
duplicate(struct range * r1,struct range * r2)560 duplicate(struct range *r1, struct range *r2)
561 {
562 int c, d;
563 int nchar;
564 int nline;
565
566 if (r1->to-r1->from != r2->to-r2->from)
567 return (0);
568 skip(0, r1->from, NULL);
569 skip(1, r2->from, NULL);
570 nchar = 0;
571 for (nline = 0; nline < r1->to - r1->from; nline++) {
572 do {
573 c = getc(fp[0]);
574 d = getc(fp[1]);
575 if (c == -1 && d == -1)
576 break;
577 if (c == -1 || d == -1)
578 errx(EXIT_FAILURE, "logic error");
579 nchar++;
580 if (c != d) {
581 repos(nchar);
582 return (0);
583 }
584 } while (c != '\n');
585 }
586 repos(nchar);
587 return (1);
588 }
589
590 static void
repos(int nchar)591 repos(int nchar)
592 {
593 int i;
594
595 for (i = 0; i < 2; i++)
596 (void)fseek(fp[i], (long)-nchar, SEEK_CUR);
597 }
598
599 /*
600 * collect an editing script for later regurgitation
601 */
602 static int
edit(struct diff * diff,bool dup,int j,int difftype)603 edit(struct diff *diff, bool dup, int j, int difftype)
604 {
605 if (!(eflag == EFLAG_UNMERGED ||
606 (!dup && eflag == EFLAG_OVERLAP ) ||
607 (dup && eflag == EFLAG_NOOVERLAP))) {
608 return (j);
609 }
610 j++;
611 overlap[j] = !dup;
612 if (!dup)
613 overlapcnt++;
614
615 de[j].type = difftype;
616 #if DEBUG
617 de[j].line = strdup(diff->line);
618 #endif /* DEBUG */
619
620 de[j].old.from = diff->old.from;
621 de[j].old.to = diff->old.to;
622 de[j].new.from = diff->new.from;
623 de[j].new.to = diff->new.to;
624 return (j);
625 }
626
627 static void
printrange(FILE * p,struct range * r)628 printrange(FILE *p, struct range *r)
629 {
630 char *line = NULL;
631 size_t len = 0;
632 int i = 1;
633
634 /* We haven't been asked to print anything */
635 if (r->from == r->to)
636 return;
637
638 if (r->from > r->to)
639 errx(EXIT_FAILURE, "invalid print range");
640
641 /*
642 * XXX-THJ: We read through all of the file for each range printed.
643 * This duplicates work and will probably impact performance on large
644 * files with lots of ranges.
645 */
646 fseek(p, 0L, SEEK_SET);
647 while (getline(&line, &len, p) > 0) {
648 if (i >= r->from)
649 printf("%s", line);
650 if (++i > r->to - 1)
651 break;
652 }
653 free(line);
654 }
655
656 /* regurgitate */
657 static void
edscript(int n)658 edscript(int n)
659 {
660 bool delete;
661 struct range *new, *old;
662
663 for (; n > 0; n--) {
664 new = &de[n].new;
665 old = &de[n].old;
666
667 delete = (new->from == new->to);
668 if (de[n].type == DIFF_TYPE1) {
669 if (delete)
670 printf("%dd\n", new->from - 1);
671 else if (old->from == new->from && old->to == new->to) {
672 printf("%dc\n", old->from);
673 printrange(fp[2], old);
674 printf(".\n");
675 }
676 continue;
677 } else {
678 if (!oflag || !overlap[n]) {
679 prange(old, delete);
680 } else {
681 printf("%da\n", old->to - 1);
682 printf("%s\n", divider);
683 }
684 printrange(fp[2], new);
685 if (!oflag || !overlap[n]) {
686 if (!delete)
687 printf(".\n");
688 } else {
689 printf("%s %s\n.\n", newmark, f3mark);
690 printf("%da\n%s %s\n.\n", old->from - 1,
691 oldmark, f1mark);
692 }
693 }
694 }
695 if (iflag)
696 printf("w\nq\n");
697
698 exit(eflag == EFLAG_NONE ? overlapcnt : 0);
699 }
700
701 /*
702 * Output an edit script to turn mine into yours, when there is a conflict
703 * between the 3 files bracket the changes. Regurgitate the diffs in reverse
704 * order to allow the ed script to track down where the lines are as changes
705 * are made.
706 */
707 static void
Ascript(int n)708 Ascript(int n)
709 {
710 int startmark;
711 bool deletenew;
712 bool deleteold;
713
714 struct range *new, *old;
715
716 for (; n > 0; n--) {
717 new = &de[n].new;
718 old = &de[n].old;
719 deletenew = (new->from == new->to);
720 deleteold = (old->from == old->to);
721
722 if (de[n].type == DIFF_TYPE2) {
723 if (!oflag || !overlap[n]) {
724 prange(old, deletenew);
725 printrange(fp[2], new);
726 } else {
727 startmark = new->to - 1;
728
729 printf("%da\n", startmark);
730 printf("%s %s\n", newmark, f3mark);
731
732 printf(".\n");
733
734 printf("%da\n", startmark -
735 (new->to - new->from));
736 printf("%s %s\n", oldmark, f2mark);
737 if (!deleteold)
738 printrange(fp[1], old);
739 printf("%s\n.\n", divider);
740 }
741
742 } else if (de[n].type == DIFF_TYPE3) {
743 startmark = old->to - 1;
744
745 if (!oflag || !overlap[n]) {
746 prange(old, deletenew);
747 printrange(fp[2], new);
748 } else {
749 printf("%da\n", startmark);
750 printf("%s %s\n", orgmark, f2mark);
751
752 if (deleteold) {
753 struct range r;
754 r.from = old->from-1;
755 r.to = new->to;
756 printrange(fp[1], &r);
757 } else
758 printrange(fp[1], old);
759
760 printf("%s\n", divider);
761 printrange(fp[2], new);
762 }
763
764 if (!oflag || !overlap[n]) {
765 if (!deletenew)
766 printf(".\n");
767 } else {
768 printf("%s %s\n.\n", newmark, f3mark);
769
770 /*
771 * Go to the start of the conflict in original
772 * file and append lines
773 */
774 printf("%da\n%s %s\n.\n",
775 startmark - (old->to - old->from),
776 oldmark, f1mark);
777 }
778 }
779 }
780 if (iflag)
781 printf("w\nq\n");
782
783 exit(overlapcnt > 0);
784 }
785
786 /*
787 * Output the merged file directly (don't generate an ed script). When
788 * regurgitating diffs we need to walk forward through the file and print any
789 * inbetween lines.
790 */
791 static void
mergescript(int i)792 mergescript(int i)
793 {
794 struct range r, *new, *old;
795 int n;
796 bool delete = false;
797
798 r.from = 1;
799 r.to = 1;
800
801 for (n = 1; n <= i; n++) {
802 new = &de[n].new;
803 old = &de[n].old;
804
805 /*
806 * Print any lines leading up to here. If we are merging don't
807 * print deleted ranges.
808 */
809 delete = (new->from == new->to);
810 if (de[n].type == DIFF_TYPE1 && delete)
811 r.to = new->from - 1;
812 else if (de[n].type == DIFF_TYPE3 && (old->from == old->to)) {
813 r.from = old->from - 1;
814 r.to = new->from;
815 } else
816 r.to = old->from;
817
818 printrange(fp[0], &r);
819 switch (de[n].type) {
820 case DIFF_TYPE1:
821 /* If this isn't a delete print it */
822 if (!delete)
823 printrange(fp[2], new);
824 break;
825 case DIFF_TYPE2:
826 printf("%s %s\n", oldmark, f2mark);
827 printrange(fp[1], old);
828 printf("%s\n", divider);
829 printrange(fp[2], new);
830 printf("%s %s\n", newmark, f3mark);
831 break;
832 case DIFF_TYPE3:
833 if (!oflag || !overlap[n]) {
834 printrange(fp[2], new);
835 } else {
836
837 printf("%s %s\n", oldmark, f1mark);
838 printrange(fp[0], old);
839
840 if (eflag != EFLAG_OVERLAP) {
841 printf("%s %s\n", orgmark, f2mark);
842 if (old->from == old->to) {
843 struct range or;
844 or.from = old->from - 1;
845 or.to = new->to;
846 printrange(fp[1], &or);
847 } else {
848 printrange(fp[1], old);
849 }
850 }
851
852 printf("%s\n", divider);
853
854 printrange(fp[2], new);
855 printf("%s %s\n", newmark, f3mark);
856 }
857 break;
858 default:
859 printf("Error: Unhandled diff type - exiting\n");
860 exit(EXIT_FAILURE);
861 }
862
863 if (old->from == old->to)
864 r.from = new->to;
865 else
866 r.from = old->to;
867 }
868
869 /*
870 * Print from the final range to the end of 'myfile'. Any deletions or
871 * additions to this file should have been handled by now.
872 *
873 * If the ranges are the same we need to rewind a line.
874 * If the new range is 0 length (from == to), we need to use the old
875 * range.
876 */
877 new = &de[n-1].new;
878 old = &de[n-1].old;
879
880 if (old->from == new->from && old->to == new->to)
881 r.from--;
882 else if (new->from == new->to)
883 r.from = old->from;
884
885 r.to = INT_MAX;
886 printrange(fp[2], &r);
887 exit(overlapcnt > 0);
888 }
889
890 static void
increase(void)891 increase(void)
892 {
893 struct diff *p;
894 char *q;
895 size_t newsz, incr;
896
897 /* are the memset(3) calls needed? */
898 newsz = szchanges == 0 ? 64 : 2 * szchanges;
899 incr = newsz - szchanges;
900
901 p = reallocarray(d13, newsz, sizeof(*p));
902 if (p == NULL)
903 err(1, NULL);
904 memset(p + szchanges, 0, incr * sizeof(*p));
905 d13 = p;
906 p = reallocarray(d23, newsz, sizeof(*p));
907 if (p == NULL)
908 err(1, NULL);
909 memset(p + szchanges, 0, incr * sizeof(*p));
910 d23 = p;
911 p = reallocarray(de, newsz, sizeof(*p));
912 if (p == NULL)
913 err(1, NULL);
914 memset(p + szchanges, 0, incr * sizeof(*p));
915 de = p;
916 q = reallocarray(overlap, newsz, 1);
917 if (q == NULL)
918 err(1, NULL);
919 memset(q + szchanges, 0, incr * 1);
920 overlap = q;
921 szchanges = newsz;
922 }
923
924
925 int
main(int argc,char ** argv)926 main(int argc, char **argv)
927 {
928 int ch, nblabels, status, m, n, kq, nke, nleft, i;
929 char *labels[] = { NULL, NULL, NULL };
930 const char *diffprog = DIFF_PATH;
931 char *file1, *file2, *file3;
932 char *diffargv[7];
933 int diffargc = 0;
934 int fd13[2], fd23[2];
935 int pd13, pd23;
936 cap_rights_t rights_ro;
937 struct kevent *e;
938
939 nblabels = 0;
940 eflag = EFLAG_NONE;
941 oflag = 0;
942 diffargv[diffargc++] = __DECONST(char *, diffprog);
943 while ((ch = getopt_long(argc, argv, OPTIONS, longopts, NULL)) != -1) {
944 switch (ch) {
945 case '3':
946 eflag = EFLAG_NOOVERLAP;
947 break;
948 case 'a':
949 diffargv[diffargc++] = __DECONST(char *, "-a");
950 break;
951 case 'A':
952 Aflag = 1;
953 break;
954 case 'e':
955 eflag = EFLAG_UNMERGED;
956 break;
957 case 'E':
958 eflag = EFLAG_OVERLAP;
959 oflag = 1;
960 break;
961 case 'i':
962 iflag = 1;
963 break;
964 case 'L':
965 oflag = 1;
966 if (nblabels >= 3)
967 errx(2, "too many file label options");
968 labels[nblabels++] = optarg;
969 break;
970 case 'm':
971 Aflag = 1;
972 oflag = 1;
973 mflag = 1;
974 break;
975 case 'T':
976 Tflag = 1;
977 break;
978 case 'x':
979 eflag = EFLAG_OVERLAP;
980 break;
981 case 'X':
982 oflag = 1;
983 eflag = EFLAG_OVERLAP;
984 break;
985 case DIFFPROG_OPT:
986 diffprog = optarg;
987 break;
988 case STRIPCR_OPT:
989 strip_cr = 1;
990 diffargv[diffargc++] = __DECONST(char *, "--strip-trailing-cr");
991 break;
992 case HELP_OPT:
993 usage();
994 exit(0);
995 case VERSION_OPT:
996 printf("%s\n", diff3_version);
997 exit(0);
998 }
999 }
1000 argc -= optind;
1001 argv += optind;
1002
1003 if (Aflag) {
1004 if (eflag == EFLAG_NONE)
1005 eflag = EFLAG_UNMERGED;
1006 oflag = 1;
1007 }
1008
1009 if (argc != 3) {
1010 usage();
1011 exit(2);
1012 }
1013
1014 if (caph_limit_stdio() == -1)
1015 err(2, "unable to limit stdio");
1016
1017 cap_rights_init(&rights_ro, CAP_READ, CAP_FSTAT, CAP_SEEK);
1018
1019 kq = kqueue();
1020 if (kq == -1)
1021 err(2, "kqueue");
1022
1023 e = malloc(2 * sizeof(*e));
1024 if (e == NULL)
1025 err(2, "malloc");
1026
1027 /* TODO stdio */
1028 file1 = argv[0];
1029 file2 = argv[1];
1030 file3 = argv[2];
1031
1032 if (oflag) {
1033 asprintf(&f1mark, "%s",
1034 labels[0] != NULL ? labels[0] : file1);
1035 if (f1mark == NULL)
1036 err(2, "asprintf");
1037 asprintf(&f2mark, "%s",
1038 labels[1] != NULL ? labels[1] : file2);
1039 if (f2mark == NULL)
1040 err(2, "asprintf");
1041 asprintf(&f3mark, "%s",
1042 labels[2] != NULL ? labels[2] : file3);
1043 if (f3mark == NULL)
1044 err(2, "asprintf");
1045 }
1046 fp[0] = fopen(file1, "r");
1047 if (fp[0] == NULL)
1048 err(2, "Can't open %s", file1);
1049 if (caph_rights_limit(fileno(fp[0]), &rights_ro) < 0)
1050 err(2, "unable to limit rights on: %s", file1);
1051
1052 fp[1] = fopen(file2, "r");
1053 if (fp[1] == NULL)
1054 err(2, "Can't open %s", file2);
1055 if (caph_rights_limit(fileno(fp[1]), &rights_ro) < 0)
1056 err(2, "unable to limit rights on: %s", file2);
1057
1058 fp[2] = fopen(file3, "r");
1059 if (fp[2] == NULL)
1060 err(2, "Can't open %s", file3);
1061 if (caph_rights_limit(fileno(fp[2]), &rights_ro) < 0)
1062 err(2, "unable to limit rights on: %s", file3);
1063
1064 if (pipe(fd13))
1065 err(2, "pipe");
1066 if (pipe(fd23))
1067 err(2, "pipe");
1068
1069 diffargv[diffargc] = file1;
1070 diffargv[diffargc + 1] = file3;
1071 diffargv[diffargc + 2] = NULL;
1072
1073 nleft = 0;
1074 pd13 = diffexec(diffprog, diffargv, fd13);
1075 EV_SET(e + nleft , pd13, EVFILT_PROCDESC, EV_ADD, NOTE_EXIT, 0, NULL);
1076 if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1)
1077 err(2, "kevent1");
1078 nleft++;
1079
1080 diffargv[diffargc] = file2;
1081 pd23 = diffexec(diffprog, diffargv, fd23);
1082 EV_SET(e + nleft , pd23, EVFILT_PROCDESC, EV_ADD, NOTE_EXIT, 0, NULL);
1083 if (kevent(kq, e + nleft, 1, NULL, 0, NULL) == -1)
1084 err(2, "kevent2");
1085 nleft++;
1086
1087 caph_cache_catpages();
1088 if (caph_enter() < 0)
1089 err(2, "unable to enter capability mode");
1090
1091 /* parse diffs */
1092 increase();
1093 m = readin(fd13[0], &d13);
1094 n = readin(fd23[0], &d23);
1095
1096 /* waitpid cooked over pdforks */
1097 while (nleft > 0) {
1098 nke = kevent(kq, NULL, 0, e, nleft, NULL);
1099 if (nke == -1)
1100 err(2, "kevent");
1101 for (i = 0; i < nke; i++) {
1102 status = e[i].data;
1103 if (WIFEXITED(status) && WEXITSTATUS(status) >= 2)
1104 errx(2, "diff exited abnormally");
1105 else if (WIFSIGNALED(status))
1106 errx(2, "diff killed by signal %d",
1107 WTERMSIG(status));
1108 }
1109 nleft -= nke;
1110 }
1111 free(e);
1112 merge(m, n);
1113
1114 return (EXIT_SUCCESS);
1115 }
1116