1/*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4#include <sys/types.h>
5#include <sys/wait.h>
6#include <signal.h>
7#include "cache.h"
8#include "diff.h"
9#include "diffcore.h"
10
11static const char *diff_opts = "-pu";
12static unsigned char null_sha1[20] = { 0, };
13
14static int reverse_diff;
15
16static const char *external_diff(void)
17{
18 static const char *external_diff_cmd = NULL;
19 static int done_preparing = 0;
20
21 if (done_preparing)
22 return external_diff_cmd;
23
24 /*
25 * Default values above are meant to match the
26 * Linux kernel development style. Examples of
27 * alternative styles you can specify via environment
28 * variables are:
29 *
30 * GIT_DIFF_OPTS="-c";
31 */
32 if (gitenv("GIT_EXTERNAL_DIFF"))
33 external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
34
35 /* In case external diff fails... */
36 diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
37
38 done_preparing = 1;
39 return external_diff_cmd;
40}
41
42/* Help to copy the thing properly quoted for the shell safety.
43 * any single quote is replaced with '\'', and the caller is
44 * expected to enclose the result within a single quote pair.
45 *
46 * E.g.
47 * original sq_expand result
48 * name ==> name ==> 'name'
49 * a b ==> a b ==> 'a b'
50 * a'b ==> a'\''b ==> 'a'\''b'
51 */
52static char *sq_expand(const char *src)
53{
54 static char *buf = NULL;
55 int cnt, c;
56 const char *cp;
57 char *bp;
58
59 /* count bytes needed to store the quoted string. */
60 for (cnt = 1, cp = src; *cp; cnt++, cp++)
61 if (*cp == '\'')
62 cnt += 3;
63
64 buf = xmalloc(cnt);
65 bp = buf;
66 while ((c = *src++)) {
67 if (c != '\'')
68 *bp++ = c;
69 else {
70 bp = strcpy(bp, "'\\''");
71 bp += 4;
72 }
73 }
74 *bp = 0;
75 return buf;
76}
77
78static struct diff_tempfile {
79 const char *name; /* filename external diff should read from */
80 char hex[41];
81 char mode[10];
82 char tmp_path[50];
83} diff_temp[2];
84
85static void builtin_diff(const char *name_a,
86 const char *name_b,
87 struct diff_tempfile *temp,
88 const char *xfrm_msg)
89{
90 int i, next_at, cmd_size;
91 const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
92 const char *diff_arg = "'%s' '%s'||:"; /* "||:" is to return 0 */
93 const char *input_name_sq[2];
94 const char *path0[2];
95 const char *path1[2];
96 const char *name_sq[2];
97 char *cmd;
98
99 name_sq[0] = sq_expand(name_a);
100 name_sq[1] = sq_expand(name_b);
101
102 /* diff_cmd and diff_arg have 6 %s in total which makes
103 * the sum of these strings 12 bytes larger than required.
104 * we use 2 spaces around diff-opts, and we need to count
105 * terminating NUL, so we subtract 9 here.
106 */
107 cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
108 strlen(diff_arg) - 9);
109 for (i = 0; i < 2; i++) {
110 input_name_sq[i] = sq_expand(temp[i].name);
111 if (!strcmp(temp[i].name, "/dev/null")) {
112 path0[i] = "/dev/null";
113 path1[i] = "";
114 } else {
115 path0[i] = i ? "b/" : "a/";
116 path1[i] = name_sq[i];
117 }
118 cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
119 strlen(input_name_sq[i]));
120 }
121
122 cmd = xmalloc(cmd_size);
123
124 next_at = 0;
125 next_at += snprintf(cmd+next_at, cmd_size-next_at,
126 diff_cmd,
127 path0[0], path1[0], path0[1], path1[1]);
128 next_at += snprintf(cmd+next_at, cmd_size-next_at,
129 " %s ", diff_opts);
130 next_at += snprintf(cmd+next_at, cmd_size-next_at,
131 diff_arg, input_name_sq[0], input_name_sq[1]);
132
133 printf("diff --git a/%s b/%s\n", name_a, name_b);
134 if (!path1[0][0])
135 printf("new file mode %s\n", temp[1].mode);
136 else if (!path1[1][0])
137 printf("deleted file mode %s\n", temp[0].mode);
138 else {
139 if (strcmp(temp[0].mode, temp[1].mode)) {
140 printf("old mode %s\n", temp[0].mode);
141 printf("new mode %s\n", temp[1].mode);
142 }
143 if (xfrm_msg && xfrm_msg[0])
144 fputs(xfrm_msg, stdout);
145
146 if (strncmp(temp[0].mode, temp[1].mode, 3))
147 /* we do not run diff between different kind
148 * of objects.
149 */
150 exit(0);
151 }
152 fflush(NULL);
153 execlp("/bin/sh","sh", "-c", cmd, NULL);
154}
155
156struct diff_filespec *alloc_filespec(const char *path)
157{
158 int namelen = strlen(path);
159 struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
160 spec->path = (char *)(spec + 1);
161 strcpy(spec->path, path);
162 spec->should_free = spec->should_munmap = 0;
163 spec->xfrm_flags = 0;
164 spec->size = 0;
165 spec->data = NULL;
166 spec->mode = 0;
167 memset(spec->sha1, 0, 20);
168 return spec;
169}
170
171void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
172 unsigned short mode)
173{
174 if (mode) { /* just playing defensive */
175 spec->mode = mode;
176 memcpy(spec->sha1, sha1, 20);
177 spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
178 }
179}
180
181/*
182 * Given a name and sha1 pair, if the dircache tells us the file in
183 * the work tree has that object contents, return true, so that
184 * prepare_temp_file() does not have to inflate and extract.
185 */
186static int work_tree_matches(const char *name, const unsigned char *sha1)
187{
188 struct cache_entry *ce;
189 struct stat st;
190 int pos, len;
191
192 /* We do not read the cache ourselves here, because the
193 * benchmark with my previous version that always reads cache
194 * shows that it makes things worse for diff-tree comparing
195 * two linux-2.6 kernel trees in an already checked out work
196 * tree. This is because most diff-tree comparisons deal with
197 * only a small number of files, while reading the cache is
198 * expensive for a large project, and its cost outweighs the
199 * savings we get by not inflating the object to a temporary
200 * file. Practically, this code only helps when we are used
201 * by diff-cache --cached, which does read the cache before
202 * calling us.
203 */
204 if (!active_cache)
205 return 0;
206
207 len = strlen(name);
208 pos = cache_name_pos(name, len);
209 if (pos < 0)
210 return 0;
211 ce = active_cache[pos];
212 if ((lstat(name, &st) < 0) ||
213 !S_ISREG(st.st_mode) || /* careful! */
214 ce_match_stat(ce, &st) ||
215 memcmp(sha1, ce->sha1, 20))
216 return 0;
217 /* we return 1 only when we can stat, it is a regular file,
218 * stat information matches, and sha1 recorded in the cache
219 * matches. I.e. we know the file in the work tree really is
220 * the same as the <name, sha1> pair.
221 */
222 return 1;
223}
224
225/*
226 * While doing rename detection and pickaxe operation, we may need to
227 * grab the data for the blob (or file) for our own in-core comparison.
228 * diff_filespec has data and size fields for this purpose.
229 */
230int diff_populate_filespec(struct diff_filespec *s)
231{
232 int err = 0;
233 if (!DIFF_FILE_VALID(s))
234 die("internal error: asking to populate invalid file.");
235 if (S_ISDIR(s->mode))
236 return -1;
237
238 if (s->data)
239 return err;
240 if (!s->sha1_valid ||
241 work_tree_matches(s->path, s->sha1)) {
242 struct stat st;
243 int fd;
244 if (lstat(s->path, &st) < 0) {
245 if (errno == ENOENT) {
246 err_empty:
247 err = -1;
248 empty:
249 s->data = "";
250 s->size = 0;
251 return err;
252 }
253 }
254 s->size = st.st_size;
255 if (!s->size)
256 goto empty;
257 if (S_ISLNK(st.st_mode)) {
258 int ret;
259 s->data = xmalloc(s->size);
260 s->should_free = 1;
261 ret = readlink(s->path, s->data, s->size);
262 if (ret < 0) {
263 free(s->data);
264 goto err_empty;
265 }
266 return 0;
267 }
268 fd = open(s->path, O_RDONLY);
269 if (fd < 0)
270 goto err_empty;
271 s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
272 s->should_munmap = 1;
273 close(fd);
274 }
275 else {
276 char type[20];
277 s->data = read_sha1_file(s->sha1, type, &s->size);
278 s->should_free = 1;
279 }
280 return 0;
281}
282
283void diff_free_filespec_data(struct diff_filespec *s)
284{
285 if (s->should_free)
286 free(s->data);
287 else if (s->should_munmap)
288 munmap(s->data, s->size);
289 s->should_free = s->should_munmap = 0;
290 s->data = NULL;
291}
292
293static void prep_temp_blob(struct diff_tempfile *temp,
294 void *blob,
295 unsigned long size,
296 unsigned char *sha1,
297 int mode)
298{
299 int fd;
300
301 strcpy(temp->tmp_path, ".diff_XXXXXX");
302 fd = mkstemp(temp->tmp_path);
303 if (fd < 0)
304 die("unable to create temp-file");
305 if (write(fd, blob, size) != size)
306 die("unable to write temp-file");
307 close(fd);
308 temp->name = temp->tmp_path;
309 strcpy(temp->hex, sha1_to_hex(sha1));
310 temp->hex[40] = 0;
311 sprintf(temp->mode, "%06o", mode);
312}
313
314static void prepare_temp_file(const char *name,
315 struct diff_tempfile *temp,
316 struct diff_filespec *one)
317{
318 if (!DIFF_FILE_VALID(one)) {
319 not_a_valid_file:
320 /* A '-' entry produces this for file-2, and
321 * a '+' entry produces this for file-1.
322 */
323 temp->name = "/dev/null";
324 strcpy(temp->hex, ".");
325 strcpy(temp->mode, ".");
326 return;
327 }
328
329 if (!one->sha1_valid ||
330 work_tree_matches(name, one->sha1)) {
331 struct stat st;
332 if (lstat(name, &st) < 0) {
333 if (errno == ENOENT)
334 goto not_a_valid_file;
335 die("stat(%s): %s", name, strerror(errno));
336 }
337 if (S_ISLNK(st.st_mode)) {
338 int ret;
339 char *buf, buf_[1024];
340 buf = ((sizeof(buf_) < st.st_size) ?
341 xmalloc(st.st_size) : buf_);
342 ret = readlink(name, buf, st.st_size);
343 if (ret < 0)
344 die("readlink(%s)", name);
345 prep_temp_blob(temp, buf, st.st_size,
346 (one->sha1_valid ?
347 one->sha1 : null_sha1),
348 (one->sha1_valid ?
349 one->mode : S_IFLNK));
350 }
351 else {
352 /* we can borrow from the file in the work tree */
353 temp->name = name;
354 if (!one->sha1_valid)
355 strcpy(temp->hex, sha1_to_hex(null_sha1));
356 else
357 strcpy(temp->hex, sha1_to_hex(one->sha1));
358 sprintf(temp->mode, "%06o",
359 S_IFREG |ce_permissions(st.st_mode));
360 }
361 return;
362 }
363 else {
364 if (diff_populate_filespec(one))
365 die("cannot read data blob for %s", one->path);
366 prep_temp_blob(temp, one->data, one->size,
367 one->sha1, one->mode);
368 }
369}
370
371static void remove_tempfile(void)
372{
373 int i;
374
375 for (i = 0; i < 2; i++)
376 if (diff_temp[i].name == diff_temp[i].tmp_path) {
377 unlink(diff_temp[i].name);
378 diff_temp[i].name = NULL;
379 }
380}
381
382static void remove_tempfile_on_signal(int signo)
383{
384 remove_tempfile();
385}
386
387/* An external diff command takes:
388 *
389 * diff-cmd name infile1 infile1-sha1 infile1-mode \
390 * infile2 infile2-sha1 infile2-mode [ rename-to ]
391 *
392 */
393static void run_external_diff(const char *name,
394 const char *other,
395 struct diff_filespec *one,
396 struct diff_filespec *two,
397 const char *xfrm_msg)
398{
399 struct diff_tempfile *temp = diff_temp;
400 pid_t pid;
401 int status;
402 static int atexit_asked = 0;
403
404 if (one && two) {
405 prepare_temp_file(name, &temp[0], one);
406 prepare_temp_file(other ? : name, &temp[1], two);
407 if (! atexit_asked &&
408 (temp[0].name == temp[0].tmp_path ||
409 temp[1].name == temp[1].tmp_path)) {
410 atexit_asked = 1;
411 atexit(remove_tempfile);
412 }
413 signal(SIGINT, remove_tempfile_on_signal);
414 }
415
416 fflush(NULL);
417 pid = fork();
418 if (pid < 0)
419 die("unable to fork");
420 if (!pid) {
421 const char *pgm = external_diff();
422 if (pgm) {
423 if (one && two) {
424 const char *exec_arg[10];
425 const char **arg = &exec_arg[0];
426 *arg++ = pgm;
427 *arg++ = name;
428 *arg++ = temp[0].name;
429 *arg++ = temp[0].hex;
430 *arg++ = temp[0].mode;
431 *arg++ = temp[1].name;
432 *arg++ = temp[1].hex;
433 *arg++ = temp[1].mode;
434 if (other) {
435 *arg++ = other;
436 *arg++ = xfrm_msg;
437 }
438 *arg = NULL;
439 execvp(pgm, (char *const*) exec_arg);
440 }
441 else
442 execlp(pgm, pgm, name, NULL);
443 }
444 /*
445 * otherwise we use the built-in one.
446 */
447 if (one && two)
448 builtin_diff(name, other ? : name, temp, xfrm_msg);
449 else
450 printf("* Unmerged path %s\n", name);
451 exit(0);
452 }
453 if (waitpid(pid, &status, 0) < 0 ||
454 !WIFEXITED(status) || WEXITSTATUS(status)) {
455 /* Earlier we did not check the exit status because
456 * diff exits non-zero if files are different, and
457 * we are not interested in knowing that. It was a
458 * mistake which made it harder to quit a diff-*
459 * session that uses the git-apply-patch-script as
460 * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
461 * should also exit non-zero only when it wants to
462 * abort the entire diff-* session.
463 */
464 remove_tempfile();
465 fprintf(stderr, "external diff died, stopping at %s.\n", name);
466 exit(1);
467 }
468 remove_tempfile();
469}
470
471void diff_setup(int reverse_diff_)
472{
473 reverse_diff = reverse_diff_;
474}
475
476struct diff_queue_struct diff_queued_diff;
477
478void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
479{
480 if (queue->alloc <= queue->nr) {
481 queue->alloc = alloc_nr(queue->alloc);
482 queue->queue = xrealloc(queue->queue,
483 sizeof(dp) * queue->alloc);
484 }
485 queue->queue[queue->nr++] = dp;
486}
487
488struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
489 struct diff_filespec *one,
490 struct diff_filespec *two)
491{
492 struct diff_filepair *dp = xmalloc(sizeof(*dp));
493 dp->one = one;
494 dp->two = two;
495 dp->score = 0;
496 dp->orig_order = queue->nr;
497 dp->rename_rank = 0;
498 diff_q(queue, dp);
499 return dp;
500}
501
502static void diff_flush_raw(struct diff_filepair *p,
503 int line_termination,
504 int inter_name_termination)
505{
506 int two_paths;
507 char status[10];
508 switch (p->status) {
509 case 'C': case 'R':
510 two_paths = 1;
511 sprintf(status, "%c%1d", p->status, p->score);
512 break;
513 default:
514 two_paths = 0;
515 status[0] = p->status;
516 status[1] = 0;
517 break;
518 }
519 printf(":%06o %06o %s ",
520 p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
521 printf("%s %s%c%s",
522 sha1_to_hex(p->two->sha1),
523 status,
524 inter_name_termination,
525 p->one->path);
526 if (two_paths)
527 printf("%c%s", inter_name_termination, p->two->path);
528 putchar(line_termination);
529}
530
531int diff_unmodified_pair(struct diff_filepair *p)
532{
533 /* This function is written stricter than necessary to support
534 * the currently implemented transformers, but the idea is to
535 * let transformers to produce diff_filepairs any way they want,
536 * and filter and clean them up here before producing the output.
537 */
538 struct diff_filespec *one, *two;
539
540 if (DIFF_PAIR_UNMERGED(p))
541 return 0; /* unmerged is interesting */
542
543 one = p->one;
544 two = p->two;
545
546 /* deletion, addition, mode change and renames are all interesting. */
547 if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
548 (one->mode != two->mode) ||
549 strcmp(one->path, two->path))
550 return 0;
551
552 /* both are valid and point at the same path. that is, we are
553 * dealing with a change.
554 */
555 if (one->sha1_valid && two->sha1_valid &&
556 !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
557 return 1; /* no change */
558 if (!one->sha1_valid && !two->sha1_valid)
559 return 1; /* both look at the same file on the filesystem. */
560 return 0;
561}
562
563static void diff_flush_patch(struct diff_filepair *p)
564{
565 const char *name, *other;
566 char msg_[PATH_MAX*2+200], *msg;
567
568 if (diff_unmodified_pair(p))
569 return;
570
571 name = p->one->path;
572 other = (strcmp(name, p->two->path) ? p->two->path : NULL);
573 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
574 (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
575 return; /* no tree diffs in patch format */
576
577 switch (p->status) {
578 case 'C':
579 sprintf(msg_,
580 "similarity index %d%%\n"
581 "copy from %s\n"
582 "copy to %s\n",
583 (int)(0.5 + p->score * 100.0/MAX_SCORE),
584 p->one->path, p->two->path);
585 msg = msg_;
586 break;
587 case 'R':
588 sprintf(msg_,
589 "similarity index %d%%\n"
590 "rename old %s\n"
591 "rename new %s\n",
592 (int)(0.5 + p->score * 100.0/MAX_SCORE),
593 p->one->path, p->two->path);
594 msg = msg_;
595 break;
596 default:
597 msg = NULL;
598 }
599
600 if (DIFF_PAIR_UNMERGED(p))
601 run_external_diff(name, NULL, NULL, NULL, NULL);
602 else
603 run_external_diff(name, other, p->one, p->two, msg);
604}
605
606int diff_needs_to_stay(struct diff_queue_struct *q, int i,
607 struct diff_filespec *it)
608{
609 /* If it will be used in later entry (either stay or used
610 * as the source of rename/copy), we need to copy, not rename.
611 */
612 while (i < q->nr) {
613 struct diff_filepair *p = q->queue[i++];
614 if (!DIFF_FILE_VALID(p->two))
615 continue; /* removed is fine */
616 if (strcmp(p->one->path, it->path))
617 continue; /* not relevant */
618
619 /* p has its src set to *it and it is not a delete;
620 * it will be used for in-place change, rename/copy,
621 * or just stays there. We cannot rename it out.
622 */
623 return 1;
624 }
625 return 0;
626}
627
628int diff_queue_is_empty(void)
629{
630 struct diff_queue_struct *q = &diff_queued_diff;
631 return q->nr == 0;
632}
633
634static void diff_resolve_rename_copy(void)
635{
636 int i;
637 struct diff_queue_struct *q = &diff_queued_diff;
638 for (i = 0; i < q->nr; i++) {
639 struct diff_filepair *p = q->queue[i];
640 p->status = 0;
641 if (DIFF_PAIR_UNMERGED(p))
642 p->status = 'U';
643 else if (!DIFF_FILE_VALID((p)->one))
644 p->status = 'N';
645 else if (!DIFF_FILE_VALID((p)->two)) {
646 /* maybe earlier one said 'R', meaning
647 * it will take it, in which case we do
648 * not need to keep 'D'.
649 */
650 int j;
651 for (j = 0; j < i; j++) {
652 struct diff_filepair *pp = q->queue[j];
653 if (pp->status == 'R' &&
654 !strcmp(pp->one->path, p->one->path))
655 break;
656 }
657 if (j < i)
658 continue;
659 p->status = 'D';
660 }
661 else if (strcmp(p->one->path, p->two->path)) {
662 /* This is rename or copy. Which one is it? */
663 if (diff_needs_to_stay(q, i+1, p->one))
664 p->status = 'C';
665 else
666 p->status = 'R';
667 }
668 else if (memcmp(p->one->sha1, p->two->sha1, 20))
669 p->status = 'M';
670 else {
671 /* we do not need this one */
672 p->status = 0;
673 }
674 }
675}
676
677void diff_flush(int diff_output_style, int resolve_rename_copy)
678{
679 struct diff_queue_struct *q = &diff_queued_diff;
680 int i;
681 int line_termination = '\n';
682 int inter_name_termination = '\t';
683
684 if (diff_output_style == DIFF_FORMAT_MACHINE)
685 line_termination = inter_name_termination = 0;
686 if (resolve_rename_copy)
687 diff_resolve_rename_copy();
688
689 for (i = 0; i < q->nr; i++) {
690 struct diff_filepair *p = q->queue[i];
691 if (p->status == 0)
692 continue;
693 switch (diff_output_style) {
694 case DIFF_FORMAT_PATCH:
695 diff_flush_patch(p);
696 break;
697 case DIFF_FORMAT_HUMAN:
698 case DIFF_FORMAT_MACHINE:
699 diff_flush_raw(p, line_termination,
700 inter_name_termination);
701 break;
702 }
703 }
704 for (i = 0; i < q->nr; i++) {
705 struct diff_filepair *p = q->queue[i];
706 diff_free_filespec_data(p->one);
707 diff_free_filespec_data(p->two);
708 free(p);
709 }
710 free(q->queue);
711 q->queue = NULL;
712 q->nr = q->alloc = 0;
713}
714
715void diff_addremove(int addremove, unsigned mode,
716 const unsigned char *sha1,
717 const char *base, const char *path)
718{
719 char concatpath[PATH_MAX];
720 struct diff_filespec *one, *two;
721
722 /* This may look odd, but it is a preparation for
723 * feeding "there are unchanged files which should
724 * not produce diffs, but when you are doing copy
725 * detection you would need them, so here they are"
726 * entries to the diff-core. They will be prefixed
727 * with something like '=' or '*' (I haven't decided
728 * which but should not make any difference).
729 * Feeding the same new and old to diff_change()
730 * also has the same effect.
731 * Before the final output happens, they are pruned after
732 * merged into rename/copy pairs as appropriate.
733 */
734 if (reverse_diff)
735 addremove = (addremove == '+' ? '-' :
736 addremove == '-' ? '+' : addremove);
737
738 if (!path) path = "";
739 sprintf(concatpath, "%s%s", base, path);
740 one = alloc_filespec(concatpath);
741 two = alloc_filespec(concatpath);
742
743 if (addremove != '+')
744 fill_filespec(one, sha1, mode);
745 if (addremove != '-')
746 fill_filespec(two, sha1, mode);
747
748 diff_queue(&diff_queued_diff, one, two);
749}
750
751void diff_helper_input(unsigned old_mode,
752 unsigned new_mode,
753 const unsigned char *old_sha1,
754 const unsigned char *new_sha1,
755 const char *old_path,
756 int status,
757 int score,
758 const char *new_path)
759{
760 struct diff_filespec *one, *two;
761 struct diff_filepair *dp;
762
763 one = alloc_filespec(old_path);
764 two = alloc_filespec(new_path);
765 if (old_mode)
766 fill_filespec(one, old_sha1, old_mode);
767 if (new_mode)
768 fill_filespec(two, new_sha1, new_mode);
769 dp = diff_queue(&diff_queued_diff, one, two);
770 dp->score = score;
771 dp->status = status;
772}
773
774void diff_change(unsigned old_mode, unsigned new_mode,
775 const unsigned char *old_sha1,
776 const unsigned char *new_sha1,
777 const char *base, const char *path)
778{
779 char concatpath[PATH_MAX];
780 struct diff_filespec *one, *two;
781
782 if (reverse_diff) {
783 unsigned tmp;
784 const unsigned char *tmp_c;
785 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
786 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
787 }
788 if (!path) path = "";
789 sprintf(concatpath, "%s%s", base, path);
790 one = alloc_filespec(concatpath);
791 two = alloc_filespec(concatpath);
792 fill_filespec(one, old_sha1, old_mode);
793 fill_filespec(two, new_sha1, new_mode);
794
795 diff_queue(&diff_queued_diff, one, two);
796}
797
798void diff_unmerge(const char *path)
799{
800 struct diff_filespec *one, *two;
801 one = alloc_filespec(path);
802 two = alloc_filespec(path);
803 diff_queue(&diff_queued_diff, one, two);
804}