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diff.c: return pattern entry pointer rather than just the hunk header pattern
[git/mjg.git] / builtin-merge-recursive.c
blob43e55bf90154c51b94527b2ab7eb7c60fe36e9ec
1 /*
2 * Recursive Merge algorithm stolen from git-merge-recursive.py by
3 * Fredrik Kuivinen.
4 * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
5 */
6 #include "cache.h"
7 #include "cache-tree.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "builtin.h"
11 #include "tree-walk.h"
12 #include "diff.h"
13 #include "diffcore.h"
14 #include "tag.h"
15 #include "unpack-trees.h"
16 #include "string-list.h"
17 #include "xdiff-interface.h"
18 #include "ll-merge.h"
19 #include "interpolate.h"
20 #include "attr.h"
21 #include "merge-recursive.h"
22
23 static int subtree_merge;
24
25 static struct tree *shift_tree_object(struct tree *one, struct tree *two)
26 {
27 unsigned char shifted[20];
28
29 /*
30 * NEEDSWORK: this limits the recursion depth to hardcoded
31 * value '2' to avoid excessive overhead.
32 */
33 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
34 if (!hashcmp(two->object.sha1, shifted))
35 return two;
36 return lookup_tree(shifted);
37 }
38
39 /*
40 * A virtual commit has
41 * - (const char *)commit->util set to the name, and
42 * - *(int *)commit->object.sha1 set to the virtual id.
43 */
44
45 static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
46 {
47 struct commit *commit = xcalloc(1, sizeof(struct commit));
48 static unsigned virtual_id = 1;
49 commit->tree = tree;
50 commit->util = (void*)comment;
51 *(int*)commit->object.sha1 = virtual_id++;
52 /* avoid warnings */
53 commit->object.parsed = 1;
54 return commit;
55 }
56
57 /*
58 * Since we use get_tree_entry(), which does not put the read object into
59 * the object pool, we cannot rely on a == b.
60 */
61 static int sha_eq(const unsigned char *a, const unsigned char *b)
62 {
63 if (!a && !b)
64 return 2;
65 return a && b && hashcmp(a, b) == 0;
66 }
67
68 /*
69 * Since we want to write the index eventually, we cannot reuse the index
70 * for these (temporary) data.
71 */
72 struct stage_data
73 {
74 struct
75 {
76 unsigned mode;
77 unsigned char sha[20];
78 } stages[4];
79 unsigned processed:1;
80 };
81
82 static struct string_list current_file_set = {NULL, 0, 0, 1};
83 static struct string_list current_directory_set = {NULL, 0, 0, 1};
84
85 static int call_depth = 0;
86 static int verbosity = 2;
87 static int diff_rename_limit = -1;
88 static int merge_rename_limit = -1;
89 static int buffer_output = 1;
90 static struct strbuf obuf = STRBUF_INIT;
91
92 static int show(int v)
93 {
94 return (!call_depth && verbosity >= v) || verbosity >= 5;
95 }
96
97 static void flush_output(void)
98 {
99 if (obuf.len) {
100 fputs(obuf.buf, stdout);
101 strbuf_reset(&obuf);
102 }
103 }
104
105 static void output(int v, const char *fmt, ...)
106 {
107 int len;
108 va_list ap;
109
110 if (!show(v))
111 return;
112
113 strbuf_grow(&obuf, call_depth * 2 + 2);
114 memset(obuf.buf + obuf.len, ' ', call_depth * 2);
115 strbuf_setlen(&obuf, obuf.len + call_depth * 2);
116
117 va_start(ap, fmt);
118 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
119 va_end(ap);
120
121 if (len < 0)
122 len = 0;
123 if (len >= strbuf_avail(&obuf)) {
124 strbuf_grow(&obuf, len + 2);
125 va_start(ap, fmt);
126 len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
127 va_end(ap);
128 if (len >= strbuf_avail(&obuf)) {
129 die("this should not happen, your snprintf is broken");
130 }
131 }
132 strbuf_setlen(&obuf, obuf.len + len);
133 strbuf_add(&obuf, "\n", 1);
134 if (!buffer_output)
135 flush_output();
136 }
137
138 static void output_commit_title(struct commit *commit)
139 {
140 int i;
141 flush_output();
142 for (i = call_depth; i--;)
143 fputs(" ", stdout);
144 if (commit->util)
145 printf("virtual %s\n", (char *)commit->util);
146 else {
147 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
148 if (parse_commit(commit) != 0)
149 printf("(bad commit)\n");
150 else {
151 const char *s;
152 int len;
153 for (s = commit->buffer; *s; s++)
154 if (*s == '\n' && s[1] == '\n') {
155 s += 2;
156 break;
157 }
158 for (len = 0; s[len] && '\n' != s[len]; len++)
159 ; /* do nothing */
160 printf("%.*s\n", len, s);
161 }
162 }
163 }
164
165 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
166 const char *path, int stage, int refresh, int options)
167 {
168 struct cache_entry *ce;
169 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
170 if (!ce)
171 return error("addinfo_cache failed for path '%s'", path);
172 return add_cache_entry(ce, options);
173 }
174
175 /*
176 * This is a global variable which is used in a number of places but
177 * only written to in the 'merge' function.
178 *
179 * index_only == 1 => Don't leave any non-stage 0 entries in the cache and
180 * don't update the working directory.
181 * 0 => Leave unmerged entries in the cache and update
182 * the working directory.
183 */
184 static int index_only = 0;
185
186 static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
187 {
188 parse_tree(tree);
189 init_tree_desc(desc, tree->buffer, tree->size);
190 }
191
192 static int git_merge_trees(int index_only,
193 struct tree *common,
194 struct tree *head,
195 struct tree *merge)
196 {
197 int rc;
198 struct tree_desc t[3];
199 struct unpack_trees_options opts;
200
201 memset(&opts, 0, sizeof(opts));
202 if (index_only)
203 opts.index_only = 1;
204 else
205 opts.update = 1;
206 opts.merge = 1;
207 opts.head_idx = 2;
208 opts.fn = threeway_merge;
209 opts.src_index = &the_index;
210 opts.dst_index = &the_index;
211
212 init_tree_desc_from_tree(t+0, common);
213 init_tree_desc_from_tree(t+1, head);
214 init_tree_desc_from_tree(t+2, merge);
215
216 rc = unpack_trees(3, t, &opts);
217 cache_tree_free(&active_cache_tree);
218 return rc;
219 }
220
221 struct tree *write_tree_from_memory(void)
222 {
223 struct tree *result = NULL;
224
225 if (unmerged_cache()) {
226 int i;
227 output(0, "There are unmerged index entries:");
228 for (i = 0; i < active_nr; i++) {
229 struct cache_entry *ce = active_cache[i];
230 if (ce_stage(ce))
231 output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
232 }
233 return NULL;
234 }
235
236 if (!active_cache_tree)
237 active_cache_tree = cache_tree();
238
239 if (!cache_tree_fully_valid(active_cache_tree) &&
240 cache_tree_update(active_cache_tree,
241 active_cache, active_nr, 0, 0) < 0)
242 die("error building trees");
243
244 result = lookup_tree(active_cache_tree->sha1);
245
246 return result;
247 }
248
249 static int save_files_dirs(const unsigned char *sha1,
250 const char *base, int baselen, const char *path,
251 unsigned int mode, int stage, void *context)
252 {
253 int len = strlen(path);
254 char *newpath = xmalloc(baselen + len + 1);
255 memcpy(newpath, base, baselen);
256 memcpy(newpath + baselen, path, len);
257 newpath[baselen + len] = '\0';
258
259 if (S_ISDIR(mode))
260 string_list_insert(newpath, &current_directory_set);
261 else
262 string_list_insert(newpath, &current_file_set);
263 free(newpath);
264
265 return READ_TREE_RECURSIVE;
266 }
267
268 static int get_files_dirs(struct tree *tree)
269 {
270 int n;
271 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, NULL))
272 return 0;
273 n = current_file_set.nr + current_directory_set.nr;
274 return n;
275 }
276
277 /*
278 * Returns an index_entry instance which doesn't have to correspond to
279 * a real cache entry in Git's index.
280 */
281 static struct stage_data *insert_stage_data(const char *path,
282 struct tree *o, struct tree *a, struct tree *b,
283 struct string_list *entries)
284 {
285 struct string_list_item *item;
286 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
287 get_tree_entry(o->object.sha1, path,
288 e->stages[1].sha, &e->stages[1].mode);
289 get_tree_entry(a->object.sha1, path,
290 e->stages[2].sha, &e->stages[2].mode);
291 get_tree_entry(b->object.sha1, path,
292 e->stages[3].sha, &e->stages[3].mode);
293 item = string_list_insert(path, entries);
294 item->util = e;
295 return e;
296 }
297
298 /*
299 * Create a dictionary mapping file names to stage_data objects. The
300 * dictionary contains one entry for every path with a non-zero stage entry.
301 */
302 static struct string_list *get_unmerged(void)
303 {
304 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
305 int i;
306
307 unmerged->strdup_strings = 1;
308
309 for (i = 0; i < active_nr; i++) {
310 struct string_list_item *item;
311 struct stage_data *e;
312 struct cache_entry *ce = active_cache[i];
313 if (!ce_stage(ce))
314 continue;
315
316 item = string_list_lookup(ce->name, unmerged);
317 if (!item) {
318 item = string_list_insert(ce->name, unmerged);
319 item->util = xcalloc(1, sizeof(struct stage_data));
320 }
321 e = item->util;
322 e->stages[ce_stage(ce)].mode = ce->ce_mode;
323 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
324 }
325
326 return unmerged;
327 }
328
329 struct rename
330 {
331 struct diff_filepair *pair;
332 struct stage_data *src_entry;
333 struct stage_data *dst_entry;
334 unsigned processed:1;
335 };
336
337 /*
338 * Get information of all renames which occurred between 'o_tree' and
339 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
340 * 'b_tree') to be able to associate the correct cache entries with
341 * the rename information. 'tree' is always equal to either a_tree or b_tree.
342 */
343 static struct string_list *get_renames(struct tree *tree,
344 struct tree *o_tree,
345 struct tree *a_tree,
346 struct tree *b_tree,
347 struct string_list *entries)
348 {
349 int i;
350 struct string_list *renames;
351 struct diff_options opts;
352
353 renames = xcalloc(1, sizeof(struct string_list));
354 diff_setup(&opts);
355 DIFF_OPT_SET(&opts, RECURSIVE);
356 opts.detect_rename = DIFF_DETECT_RENAME;
357 opts.rename_limit = merge_rename_limit >= 0 ? merge_rename_limit :
358 diff_rename_limit >= 0 ? diff_rename_limit :
359 500;
360 opts.warn_on_too_large_rename = 1;
361 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
362 if (diff_setup_done(&opts) < 0)
363 die("diff setup failed");
364 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
365 diffcore_std(&opts);
366 for (i = 0; i < diff_queued_diff.nr; ++i) {
367 struct string_list_item *item;
368 struct rename *re;
369 struct diff_filepair *pair = diff_queued_diff.queue[i];
370 if (pair->status != 'R') {
371 diff_free_filepair(pair);
372 continue;
373 }
374 re = xmalloc(sizeof(*re));
375 re->processed = 0;
376 re->pair = pair;
377 item = string_list_lookup(re->pair->one->path, entries);
378 if (!item)
379 re->src_entry = insert_stage_data(re->pair->one->path,
380 o_tree, a_tree, b_tree, entries);
381 else
382 re->src_entry = item->util;
383
384 item = string_list_lookup(re->pair->two->path, entries);
385 if (!item)
386 re->dst_entry = insert_stage_data(re->pair->two->path,
387 o_tree, a_tree, b_tree, entries);
388 else
389 re->dst_entry = item->util;
390 item = string_list_insert(pair->one->path, renames);
391 item->util = re;
392 }
393 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
394 diff_queued_diff.nr = 0;
395 diff_flush(&opts);
396 return renames;
397 }
398
399 static int update_stages(const char *path, struct diff_filespec *o,
400 struct diff_filespec *a, struct diff_filespec *b,
401 int clear)
402 {
403 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
404 if (clear)
405 if (remove_file_from_cache(path))
406 return -1;
407 if (o)
408 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
409 return -1;
410 if (a)
411 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
412 return -1;
413 if (b)
414 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
415 return -1;
416 return 0;
417 }
418
419 static int remove_path(const char *name)
420 {
421 int ret;
422 char *slash, *dirs;
423
424 ret = unlink(name);
425 if (ret)
426 return ret;
427 dirs = xstrdup(name);
428 while ((slash = strrchr(name, '/'))) {
429 *slash = '\0';
430 if (rmdir(name) != 0)
431 break;
432 }
433 free(dirs);
434 return ret;
435 }
436
437 static int remove_file(int clean, const char *path, int no_wd)
438 {
439 int update_cache = index_only || clean;
440 int update_working_directory = !index_only && !no_wd;
441
442 if (update_cache) {
443 if (remove_file_from_cache(path))
444 return -1;
445 }
446 if (update_working_directory) {
447 unlink(path);
448 if (errno != ENOENT || errno != EISDIR)
449 return -1;
450 remove_path(path);
451 }
452 return 0;
453 }
454
455 static char *unique_path(const char *path, const char *branch)
456 {
457 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
458 int suffix = 0;
459 struct stat st;
460 char *p = newpath + strlen(path);
461 strcpy(newpath, path);
462 *(p++) = '~';
463 strcpy(p, branch);
464 for (; *p; ++p)
465 if ('/' == *p)
466 *p = '_';
467 while (string_list_has_string(&current_file_set, newpath) ||
468 string_list_has_string(&current_directory_set, newpath) ||
469 lstat(newpath, &st) == 0)
470 sprintf(p, "_%d", suffix++);
471
472 string_list_insert(newpath, &current_file_set);
473 return newpath;
474 }
475
476 static void flush_buffer(int fd, const char *buf, unsigned long size)
477 {
478 while (size > 0) {
479 long ret = write_in_full(fd, buf, size);
480 if (ret < 0) {
481 /* Ignore epipe */
482 if (errno == EPIPE)
483 break;
484 die("merge-recursive: %s", strerror(errno));
485 } else if (!ret) {
486 die("merge-recursive: disk full?");
487 }
488 size -= ret;
489 buf += ret;
490 }
491 }
492
493 static int make_room_for_path(const char *path)
494 {
495 int status;
496 const char *msg = "failed to create path '%s'%s";
497
498 status = safe_create_leading_directories_const(path);
499 if (status) {
500 if (status == -3) {
501 /* something else exists */
502 error(msg, path, ": perhaps a D/F conflict?");
503 return -1;
504 }
505 die(msg, path, "");
506 }
507
508 /* Successful unlink is good.. */
509 if (!unlink(path))
510 return 0;
511 /* .. and so is no existing file */
512 if (errno == ENOENT)
513 return 0;
514 /* .. but not some other error (who really cares what?) */
515 return error(msg, path, ": perhaps a D/F conflict?");
516 }
517
518 static void update_file_flags(const unsigned char *sha,
519 unsigned mode,
520 const char *path,
521 int update_cache,
522 int update_wd)
523 {
524 if (index_only)
525 update_wd = 0;
526
527 if (update_wd) {
528 enum object_type type;
529 void *buf;
530 unsigned long size;
531
532 if (S_ISGITLINK(mode))
533 die("cannot read object %s '%s': It is a submodule!",
534 sha1_to_hex(sha), path);
535
536 buf = read_sha1_file(sha, &type, &size);
537 if (!buf)
538 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
539 if (type != OBJ_BLOB)
540 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
541 if (S_ISREG(mode)) {
542 struct strbuf strbuf;
543 strbuf_init(&strbuf, 0);
544 if (convert_to_working_tree(path, buf, size, &strbuf)) {
545 free(buf);
546 size = strbuf.len;
547 buf = strbuf_detach(&strbuf, NULL);
548 }
549 }
550
551 if (make_room_for_path(path) < 0) {
552 update_wd = 0;
553 free(buf);
554 goto update_index;
555 }
556 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
557 int fd;
558 if (mode & 0100)
559 mode = 0777;
560 else
561 mode = 0666;
562 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
563 if (fd < 0)
564 die("failed to open %s: %s", path, strerror(errno));
565 flush_buffer(fd, buf, size);
566 close(fd);
567 } else if (S_ISLNK(mode)) {
568 char *lnk = xmemdupz(buf, size);
569 safe_create_leading_directories_const(path);
570 unlink(path);
571 symlink(lnk, path);
572 free(lnk);
573 } else
574 die("do not know what to do with %06o %s '%s'",
575 mode, sha1_to_hex(sha), path);
576 free(buf);
577 }
578 update_index:
579 if (update_cache)
580 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
581 }
582
583 static void update_file(int clean,
584 const unsigned char *sha,
585 unsigned mode,
586 const char *path)
587 {
588 update_file_flags(sha, mode, path, index_only || clean, !index_only);
589 }
590
591 /* Low level file merging, update and removal */
592
593 struct merge_file_info
594 {
595 unsigned char sha[20];
596 unsigned mode;
597 unsigned clean:1,
598 merge:1;
599 };
600
601 static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
602 {
603 unsigned long size;
604 enum object_type type;
605
606 if (!hashcmp(sha1, null_sha1)) {
607 mm->ptr = xstrdup("");
608 mm->size = 0;
609 return;
610 }
611
612 mm->ptr = read_sha1_file(sha1, &type, &size);
613 if (!mm->ptr || type != OBJ_BLOB)
614 die("unable to read blob object %s", sha1_to_hex(sha1));
615 mm->size = size;
616 }
617
618 static int merge_3way(mmbuffer_t *result_buf,
619 struct diff_filespec *o,
620 struct diff_filespec *a,
621 struct diff_filespec *b,
622 const char *branch1,
623 const char *branch2)
624 {
625 mmfile_t orig, src1, src2;
626 char *name1, *name2;
627 int merge_status;
628
629 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
630 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
631
632 fill_mm(o->sha1, &orig);
633 fill_mm(a->sha1, &src1);
634 fill_mm(b->sha1, &src2);
635
636 merge_status = ll_merge(result_buf, a->path, &orig,
637 &src1, name1, &src2, name2,
638 index_only);
639
640 free(name1);
641 free(name2);
642 free(orig.ptr);
643 free(src1.ptr);
644 free(src2.ptr);
645 return merge_status;
646 }
647
648 static struct merge_file_info merge_file(struct diff_filespec *o,
649 struct diff_filespec *a, struct diff_filespec *b,
650 const char *branch1, const char *branch2)
651 {
652 struct merge_file_info result;
653 result.merge = 0;
654 result.clean = 1;
655
656 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
657 result.clean = 0;
658 if (S_ISREG(a->mode)) {
659 result.mode = a->mode;
660 hashcpy(result.sha, a->sha1);
661 } else {
662 result.mode = b->mode;
663 hashcpy(result.sha, b->sha1);
664 }
665 } else {
666 if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
667 result.merge = 1;
668
669 /*
670 * Merge modes
671 */
672 if (a->mode == b->mode || a->mode == o->mode)
673 result.mode = b->mode;
674 else {
675 result.mode = a->mode;
676 if (b->mode != o->mode) {
677 result.clean = 0;
678 result.merge = 1;
679 }
680 }
681
682 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1))
683 hashcpy(result.sha, b->sha1);
684 else if (sha_eq(b->sha1, o->sha1))
685 hashcpy(result.sha, a->sha1);
686 else if (S_ISREG(a->mode)) {
687 mmbuffer_t result_buf;
688 int merge_status;
689
690 merge_status = merge_3way(&result_buf, o, a, b,
691 branch1, branch2);
692
693 if ((merge_status < 0) || !result_buf.ptr)
694 die("Failed to execute internal merge");
695
696 if (write_sha1_file(result_buf.ptr, result_buf.size,
697 blob_type, result.sha))
698 die("Unable to add %s to database",
699 a->path);
700
701 free(result_buf.ptr);
702 result.clean = (merge_status == 0);
703 } else if (S_ISGITLINK(a->mode)) {
704 result.clean = 0;
705 hashcpy(result.sha, a->sha1);
706 } else if (S_ISLNK(a->mode)) {
707 hashcpy(result.sha, a->sha1);
708
709 if (!sha_eq(a->sha1, b->sha1))
710 result.clean = 0;
711 } else {
712 die("unsupported object type in the tree");
713 }
714 }
715
716 return result;
717 }
718
719 static void conflict_rename_rename(struct rename *ren1,
720 const char *branch1,
721 struct rename *ren2,
722 const char *branch2)
723 {
724 char *del[2];
725 int delp = 0;
726 const char *ren1_dst = ren1->pair->two->path;
727 const char *ren2_dst = ren2->pair->two->path;
728 const char *dst_name1 = ren1_dst;
729 const char *dst_name2 = ren2_dst;
730 if (string_list_has_string(&current_directory_set, ren1_dst)) {
731 dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
732 output(1, "%s is a directory in %s added as %s instead",
733 ren1_dst, branch2, dst_name1);
734 remove_file(0, ren1_dst, 0);
735 }
736 if (string_list_has_string(&current_directory_set, ren2_dst)) {
737 dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
738 output(1, "%s is a directory in %s added as %s instead",
739 ren2_dst, branch1, dst_name2);
740 remove_file(0, ren2_dst, 0);
741 }
742 if (index_only) {
743 remove_file_from_cache(dst_name1);
744 remove_file_from_cache(dst_name2);
745 /*
746 * Uncomment to leave the conflicting names in the resulting tree
747 *
748 * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
749 * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
750 */
751 } else {
752 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
753 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
754 }
755 while (delp--)
756 free(del[delp]);
757 }
758
759 static void conflict_rename_dir(struct rename *ren1,
760 const char *branch1)
761 {
762 char *new_path = unique_path(ren1->pair->two->path, branch1);
763 output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
764 remove_file(0, ren1->pair->two->path, 0);
765 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
766 free(new_path);
767 }
768
769 static void conflict_rename_rename_2(struct rename *ren1,
770 const char *branch1,
771 struct rename *ren2,
772 const char *branch2)
773 {
774 char *new_path1 = unique_path(ren1->pair->two->path, branch1);
775 char *new_path2 = unique_path(ren2->pair->two->path, branch2);
776 output(1, "Renamed %s to %s and %s to %s instead",
777 ren1->pair->one->path, new_path1,
778 ren2->pair->one->path, new_path2);
779 remove_file(0, ren1->pair->two->path, 0);
780 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
781 update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
782 free(new_path2);
783 free(new_path1);
784 }
785
786 static int process_renames(struct string_list *a_renames,
787 struct string_list *b_renames,
788 const char *a_branch,
789 const char *b_branch)
790 {
791 int clean_merge = 1, i, j;
792 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
793 const struct rename *sre;
794
795 for (i = 0; i < a_renames->nr; i++) {
796 sre = a_renames->items[i].util;
797 string_list_insert(sre->pair->two->path, &a_by_dst)->util
798 = sre->dst_entry;
799 }
800 for (i = 0; i < b_renames->nr; i++) {
801 sre = b_renames->items[i].util;
802 string_list_insert(sre->pair->two->path, &b_by_dst)->util
803 = sre->dst_entry;
804 }
805
806 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
807 int compare;
808 char *src;
809 struct string_list *renames1, *renames2, *renames2Dst;
810 struct rename *ren1 = NULL, *ren2 = NULL;
811 const char *branch1, *branch2;
812 const char *ren1_src, *ren1_dst;
813
814 if (i >= a_renames->nr) {
815 compare = 1;
816 ren2 = b_renames->items[j++].util;
817 } else if (j >= b_renames->nr) {
818 compare = -1;
819 ren1 = a_renames->items[i++].util;
820 } else {
821 compare = strcmp(a_renames->items[i].string,
822 b_renames->items[j].string);
823 if (compare <= 0)
824 ren1 = a_renames->items[i++].util;
825 if (compare >= 0)
826 ren2 = b_renames->items[j++].util;
827 }
828
829 /* TODO: refactor, so that 1/2 are not needed */
830 if (ren1) {
831 renames1 = a_renames;
832 renames2 = b_renames;
833 renames2Dst = &b_by_dst;
834 branch1 = a_branch;
835 branch2 = b_branch;
836 } else {
837 struct rename *tmp;
838 renames1 = b_renames;
839 renames2 = a_renames;
840 renames2Dst = &a_by_dst;
841 branch1 = b_branch;
842 branch2 = a_branch;
843 tmp = ren2;
844 ren2 = ren1;
845 ren1 = tmp;
846 }
847 src = ren1->pair->one->path;
848
849 ren1->dst_entry->processed = 1;
850 ren1->src_entry->processed = 1;
851
852 if (ren1->processed)
853 continue;
854 ren1->processed = 1;
855
856 ren1_src = ren1->pair->one->path;
857 ren1_dst = ren1->pair->two->path;
858
859 if (ren2) {
860 const char *ren2_src = ren2->pair->one->path;
861 const char *ren2_dst = ren2->pair->two->path;
862 /* Renamed in 1 and renamed in 2 */
863 if (strcmp(ren1_src, ren2_src) != 0)
864 die("ren1.src != ren2.src");
865 ren2->dst_entry->processed = 1;
866 ren2->processed = 1;
867 if (strcmp(ren1_dst, ren2_dst) != 0) {
868 clean_merge = 0;
869 output(1, "CONFLICT (rename/rename): "
870 "Rename \"%s\"->\"%s\" in branch \"%s\" "
871 "rename \"%s\"->\"%s\" in \"%s\"%s",
872 src, ren1_dst, branch1,
873 src, ren2_dst, branch2,
874 index_only ? " (left unresolved)": "");
875 if (index_only) {
876 remove_file_from_cache(src);
877 update_file(0, ren1->pair->one->sha1,
878 ren1->pair->one->mode, src);
879 }
880 conflict_rename_rename(ren1, branch1, ren2, branch2);
881 } else {
882 struct merge_file_info mfi;
883 remove_file(1, ren1_src, 1);
884 mfi = merge_file(ren1->pair->one,
885 ren1->pair->two,
886 ren2->pair->two,
887 branch1,
888 branch2);
889 if (mfi.merge || !mfi.clean)
890 output(1, "Renamed %s->%s", src, ren1_dst);
891
892 if (mfi.merge)
893 output(2, "Auto-merged %s", ren1_dst);
894
895 if (!mfi.clean) {
896 output(1, "CONFLICT (content): merge conflict in %s",
897 ren1_dst);
898 clean_merge = 0;
899
900 if (!index_only)
901 update_stages(ren1_dst,
902 ren1->pair->one,
903 ren1->pair->two,
904 ren2->pair->two,
905 1 /* clear */);
906 }
907 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
908 }
909 } else {
910 /* Renamed in 1, maybe changed in 2 */
911 struct string_list_item *item;
912 /* we only use sha1 and mode of these */
913 struct diff_filespec src_other, dst_other;
914 int try_merge, stage = a_renames == renames1 ? 3: 2;
915
916 remove_file(1, ren1_src, index_only || stage == 3);
917
918 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
919 src_other.mode = ren1->src_entry->stages[stage].mode;
920 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
921 dst_other.mode = ren1->dst_entry->stages[stage].mode;
922
923 try_merge = 0;
924
925 if (string_list_has_string(&current_directory_set, ren1_dst)) {
926 clean_merge = 0;
927 output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
928 " directory %s added in %s",
929 ren1_src, ren1_dst, branch1,
930 ren1_dst, branch2);
931 conflict_rename_dir(ren1, branch1);
932 } else if (sha_eq(src_other.sha1, null_sha1)) {
933 clean_merge = 0;
934 output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
935 "and deleted in %s",
936 ren1_src, ren1_dst, branch1,
937 branch2);
938 update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
939 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
940 const char *new_path;
941 clean_merge = 0;
942 try_merge = 1;
943 output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
944 "%s added in %s",
945 ren1_src, ren1_dst, branch1,
946 ren1_dst, branch2);
947 new_path = unique_path(ren1_dst, branch2);
948 output(1, "Added as %s instead", new_path);
949 update_file(0, dst_other.sha1, dst_other.mode, new_path);
950 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
951 ren2 = item->util;
952 clean_merge = 0;
953 ren2->processed = 1;
954 output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
955 "Renamed %s->%s in %s",
956 ren1_src, ren1_dst, branch1,
957 ren2->pair->one->path, ren2->pair->two->path, branch2);
958 conflict_rename_rename_2(ren1, branch1, ren2, branch2);
959 } else
960 try_merge = 1;
961
962 if (try_merge) {
963 struct diff_filespec *o, *a, *b;
964 struct merge_file_info mfi;
965 src_other.path = (char *)ren1_src;
966
967 o = ren1->pair->one;
968 if (a_renames == renames1) {
969 a = ren1->pair->two;
970 b = &src_other;
971 } else {
972 b = ren1->pair->two;
973 a = &src_other;
974 }
975 mfi = merge_file(o, a, b,
976 a_branch, b_branch);
977
978 if (mfi.clean &&
979 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
980 mfi.mode == ren1->pair->two->mode)
981 /*
982 * This messaged is part of
983 * t6022 test. If you change
984 * it update the test too.
985 */
986 output(3, "Skipped %s (merged same as existing)", ren1_dst);
987 else {
988 if (mfi.merge || !mfi.clean)
989 output(1, "Renamed %s => %s", ren1_src, ren1_dst);
990 if (mfi.merge)
991 output(2, "Auto-merged %s", ren1_dst);
992 if (!mfi.clean) {
993 output(1, "CONFLICT (rename/modify): Merge conflict in %s",
994 ren1_dst);
995 clean_merge = 0;
996
997 if (!index_only)
998 update_stages(ren1_dst,
999 o, a, b, 1);
1000 }
1001 update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1002 }
1003 }
1004 }
1005 }
1006 string_list_clear(&a_by_dst, 0);
1007 string_list_clear(&b_by_dst, 0);
1008
1009 return clean_merge;
1010 }
1011
1012 static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1013 {
1014 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1015 }
1016
1017 /* Per entry merge function */
1018 static int process_entry(const char *path, struct stage_data *entry,
1019 const char *branch1,
1020 const char *branch2)
1021 {
1022 /*
1023 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1024 print_index_entry("\tpath: ", entry);
1025 */
1026 int clean_merge = 1;
1027 unsigned o_mode = entry->stages[1].mode;
1028 unsigned a_mode = entry->stages[2].mode;
1029 unsigned b_mode = entry->stages[3].mode;
1030 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1031 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1032 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1033
1034 if (o_sha && (!a_sha || !b_sha)) {
1035 /* Case A: Deleted in one */
1036 if ((!a_sha && !b_sha) ||
1037 (sha_eq(a_sha, o_sha) && !b_sha) ||
1038 (!a_sha && sha_eq(b_sha, o_sha))) {
1039 /* Deleted in both or deleted in one and
1040 * unchanged in the other */
1041 if (a_sha)
1042 output(2, "Removed %s", path);
1043 /* do not touch working file if it did not exist */
1044 remove_file(1, path, !a_sha);
1045 } else {
1046 /* Deleted in one and changed in the other */
1047 clean_merge = 0;
1048 if (!a_sha) {
1049 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1050 "and modified in %s. Version %s of %s left in tree.",
1051 path, branch1,
1052 branch2, branch2, path);
1053 update_file(0, b_sha, b_mode, path);
1054 } else {
1055 output(1, "CONFLICT (delete/modify): %s deleted in %s "
1056 "and modified in %s. Version %s of %s left in tree.",
1057 path, branch2,
1058 branch1, branch1, path);
1059 update_file(0, a_sha, a_mode, path);
1060 }
1061 }
1062
1063 } else if ((!o_sha && a_sha && !b_sha) ||
1064 (!o_sha && !a_sha && b_sha)) {
1065 /* Case B: Added in one. */
1066 const char *add_branch;
1067 const char *other_branch;
1068 unsigned mode;
1069 const unsigned char *sha;
1070 const char *conf;
1071
1072 if (a_sha) {
1073 add_branch = branch1;
1074 other_branch = branch2;
1075 mode = a_mode;
1076 sha = a_sha;
1077 conf = "file/directory";
1078 } else {
1079 add_branch = branch2;
1080 other_branch = branch1;
1081 mode = b_mode;
1082 sha = b_sha;
1083 conf = "directory/file";
1084 }
1085 if (string_list_has_string(&current_directory_set, path)) {
1086 const char *new_path = unique_path(path, add_branch);
1087 clean_merge = 0;
1088 output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
1089 "Added %s as %s",
1090 conf, path, other_branch, path, new_path);
1091 remove_file(0, path, 0);
1092 update_file(0, sha, mode, new_path);
1093 } else {
1094 output(2, "Added %s", path);
1095 update_file(1, sha, mode, path);
1096 }
1097 } else if (a_sha && b_sha) {
1098 /* Case C: Added in both (check for same permissions) and */
1099 /* case D: Modified in both, but differently. */
1100 const char *reason = "content";
1101 struct merge_file_info mfi;
1102 struct diff_filespec o, a, b;
1103
1104 if (!o_sha) {
1105 reason = "add/add";
1106 o_sha = (unsigned char *)null_sha1;
1107 }
1108 output(2, "Auto-merged %s", path);
1109 o.path = a.path = b.path = (char *)path;
1110 hashcpy(o.sha1, o_sha);
1111 o.mode = o_mode;
1112 hashcpy(a.sha1, a_sha);
1113 a.mode = a_mode;
1114 hashcpy(b.sha1, b_sha);
1115 b.mode = b_mode;
1116
1117 mfi = merge_file(&o, &a, &b,
1118 branch1, branch2);
1119
1120 clean_merge = mfi.clean;
1121 if (mfi.clean)
1122 update_file(1, mfi.sha, mfi.mode, path);
1123 else if (S_ISGITLINK(mfi.mode))
1124 output(1, "CONFLICT (submodule): Merge conflict in %s "
1125 "- needs %s", path, sha1_to_hex(b.sha1));
1126 else {
1127 output(1, "CONFLICT (%s): Merge conflict in %s",
1128 reason, path);
1129
1130 if (index_only)
1131 update_file(0, mfi.sha, mfi.mode, path);
1132 else
1133 update_file_flags(mfi.sha, mfi.mode, path,
1134 0 /* update_cache */, 1 /* update_working_directory */);
1135 }
1136 } else if (!o_sha && !a_sha && !b_sha) {
1137 /*
1138 * this entry was deleted altogether. a_mode == 0 means
1139 * we had that path and want to actively remove it.
1140 */
1141 remove_file(1, path, !a_mode);
1142 } else
1143 die("Fatal merge failure, shouldn't happen.");
1144
1145 return clean_merge;
1146 }
1147
1148 int merge_trees(struct tree *head,
1149 struct tree *merge,
1150 struct tree *common,
1151 const char *branch1,
1152 const char *branch2,
1153 struct tree **result)
1154 {
1155 int code, clean;
1156
1157 if (subtree_merge) {
1158 merge = shift_tree_object(head, merge);
1159 common = shift_tree_object(head, common);
1160 }
1161
1162 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1163 output(0, "Already uptodate!");
1164 *result = head;
1165 return 1;
1166 }
1167
1168 code = git_merge_trees(index_only, common, head, merge);
1169
1170 if (code != 0)
1171 die("merging of trees %s and %s failed",
1172 sha1_to_hex(head->object.sha1),
1173 sha1_to_hex(merge->object.sha1));
1174
1175 if (unmerged_cache()) {
1176 struct string_list *entries, *re_head, *re_merge;
1177 int i;
1178 string_list_clear(&current_file_set, 1);
1179 string_list_clear(&current_directory_set, 1);
1180 get_files_dirs(head);
1181 get_files_dirs(merge);
1182
1183 entries = get_unmerged();
1184 re_head = get_renames(head, common, head, merge, entries);
1185 re_merge = get_renames(merge, common, head, merge, entries);
1186 clean = process_renames(re_head, re_merge,
1187 branch1, branch2);
1188 for (i = 0; i < entries->nr; i++) {
1189 const char *path = entries->items[i].string;
1190 struct stage_data *e = entries->items[i].util;
1191 if (!e->processed
1192 && !process_entry(path, e, branch1, branch2))
1193 clean = 0;
1194 }
1195
1196 string_list_clear(re_merge, 0);
1197 string_list_clear(re_head, 0);
1198 string_list_clear(entries, 1);
1199
1200 }
1201 else
1202 clean = 1;
1203
1204 if (index_only)
1205 *result = write_tree_from_memory();
1206
1207 return clean;
1208 }
1209
1210 static struct commit_list *reverse_commit_list(struct commit_list *list)
1211 {
1212 struct commit_list *next = NULL, *current, *backup;
1213 for (current = list; current; current = backup) {
1214 backup = current->next;
1215 current->next = next;
1216 next = current;
1217 }
1218 return next;
1219 }
1220
1221 /*
1222 * Merge the commits h1 and h2, return the resulting virtual
1223 * commit object and a flag indicating the cleanness of the merge.
1224 */
1225 int merge_recursive(struct commit *h1,
1226 struct commit *h2,
1227 const char *branch1,
1228 const char *branch2,
1229 struct commit_list *ca,
1230 struct commit **result)
1231 {
1232 struct commit_list *iter;
1233 struct commit *merged_common_ancestors;
1234 struct tree *mrtree = mrtree;
1235 int clean;
1236
1237 if (show(4)) {
1238 output(4, "Merging:");
1239 output_commit_title(h1);
1240 output_commit_title(h2);
1241 }
1242
1243 if (!ca) {
1244 ca = get_merge_bases(h1, h2, 1);
1245 ca = reverse_commit_list(ca);
1246 }
1247
1248 if (show(5)) {
1249 output(5, "found %u common ancestor(s):", commit_list_count(ca));
1250 for (iter = ca; iter; iter = iter->next)
1251 output_commit_title(iter->item);
1252 }
1253
1254 merged_common_ancestors = pop_commit(&ca);
1255 if (merged_common_ancestors == NULL) {
1256 /* if there is no common ancestor, make an empty tree */
1257 struct tree *tree = xcalloc(1, sizeof(struct tree));
1258
1259 tree->object.parsed = 1;
1260 tree->object.type = OBJ_TREE;
1261 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1262 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1263 }
1264
1265 for (iter = ca; iter; iter = iter->next) {
1266 call_depth++;
1267 /*
1268 * When the merge fails, the result contains files
1269 * with conflict markers. The cleanness flag is
1270 * ignored, it was never actually used, as result of
1271 * merge_trees has always overwritten it: the committed
1272 * "conflicts" were already resolved.
1273 */
1274 discard_cache();
1275 merge_recursive(merged_common_ancestors, iter->item,
1276 "Temporary merge branch 1",
1277 "Temporary merge branch 2",
1278 NULL,
1279 &merged_common_ancestors);
1280 call_depth--;
1281
1282 if (!merged_common_ancestors)
1283 die("merge returned no commit");
1284 }
1285
1286 discard_cache();
1287 if (!call_depth) {
1288 read_cache();
1289 index_only = 0;
1290 } else
1291 index_only = 1;
1292
1293 clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
1294 branch1, branch2, &mrtree);
1295
1296 if (index_only) {
1297 *result = make_virtual_commit(mrtree, "merged tree");
1298 commit_list_insert(h1, &(*result)->parents);
1299 commit_list_insert(h2, &(*result)->parents->next);
1300 }
1301 flush_output();
1302 return clean;
1303 }
1304
1305 static const char *better_branch_name(const char *branch)
1306 {
1307 static char githead_env[8 + 40 + 1];
1308 char *name;
1309
1310 if (strlen(branch) != 40)
1311 return branch;
1312 sprintf(githead_env, "GITHEAD_%s", branch);
1313 name = getenv(githead_env);
1314 return name ? name : branch;
1315 }
1316
1317 static struct commit *get_ref(const char *ref)
1318 {
1319 unsigned char sha1[20];
1320 struct object *object;
1321
1322 if (get_sha1(ref, sha1))
1323 die("Could not resolve ref '%s'", ref);
1324 object = deref_tag(parse_object(sha1), ref, strlen(ref));
1325 if (!object)
1326 return NULL;
1327 if (object->type == OBJ_TREE)
1328 return make_virtual_commit((struct tree*)object,
1329 better_branch_name(ref));
1330 if (object->type != OBJ_COMMIT)
1331 return NULL;
1332 if (parse_commit((struct commit *)object))
1333 die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
1334 return (struct commit *)object;
1335 }
1336
1337 static int merge_config(const char *var, const char *value, void *cb)
1338 {
1339 if (!strcasecmp(var, "merge.verbosity")) {
1340 verbosity = git_config_int(var, value);
1341 return 0;
1342 }
1343 if (!strcasecmp(var, "diff.renamelimit")) {
1344 diff_rename_limit = git_config_int(var, value);
1345 return 0;
1346 }
1347 if (!strcasecmp(var, "merge.renamelimit")) {
1348 merge_rename_limit = git_config_int(var, value);
1349 return 0;
1350 }
1351 return git_default_config(var, value, cb);
1352 }
1353
1354 int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
1355 {
1356 static const char *bases[20];
1357 static unsigned bases_count = 0;
1358 int i, clean;
1359 const char *branch1, *branch2;
1360 struct commit *result, *h1, *h2;
1361 struct commit_list *ca = NULL;
1362 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1363 int index_fd;
1364
1365 if (argv[0]) {
1366 int namelen = strlen(argv[0]);
1367 if (8 < namelen &&
1368 !strcmp(argv[0] + namelen - 8, "-subtree"))
1369 subtree_merge = 1;
1370 }
1371
1372 git_config(merge_config, NULL);
1373 if (getenv("GIT_MERGE_VERBOSITY"))
1374 verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1375
1376 if (argc < 4)
1377 die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
1378
1379 for (i = 1; i < argc; ++i) {
1380 if (!strcmp(argv[i], "--"))
1381 break;
1382 if (bases_count < sizeof(bases)/sizeof(*bases))
1383 bases[bases_count++] = argv[i];
1384 }
1385 if (argc - i != 3) /* "--" "<head>" "<remote>" */
1386 die("Not handling anything other than two heads merge.");
1387 if (verbosity >= 5)
1388 buffer_output = 0;
1389
1390 branch1 = argv[++i];
1391 branch2 = argv[++i];
1392
1393 h1 = get_ref(branch1);
1394 h2 = get_ref(branch2);
1395
1396 branch1 = better_branch_name(branch1);
1397 branch2 = better_branch_name(branch2);
1398
1399 if (show(3))
1400 printf("Merging %s with %s\n", branch1, branch2);
1401
1402 index_fd = hold_locked_index(lock, 1);
1403
1404 for (i = 0; i < bases_count; i++) {
1405 struct commit *ancestor = get_ref(bases[i]);
1406 ca = commit_list_insert(ancestor, &ca);
1407 }
1408 clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
1409
1410 if (active_cache_changed &&
1411 (write_cache(index_fd, active_cache, active_nr) ||
1412 commit_locked_index(lock)))
1413 die ("unable to write %s", get_index_file());
1414
1415 return clean ? 0: 1;
1416 }
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