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 "attr.h"
20#include "merge-recursive.h"
21#include "dir.h"
22static struct tree *shift_tree_object(struct tree *one, struct tree *two)
24{
25 unsigned char shifted[20];
26 /*
28 * NEEDSWORK: this limits the recursion depth to hardcoded
29 * value '2' to avoid excessive overhead.
30 */
31 shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
32 if (!hashcmp(two->object.sha1, shifted))
33 return two;
34 return lookup_tree(shifted);
35}
36/*
38 * A virtual commit has (const char *)commit->util set to the name.
39 */
40static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
42{
43 struct commit *commit = xcalloc(1, sizeof(struct commit));
44 commit->tree = tree;
45 commit->util = (void*)comment;
46 /* avoid warnings */
47 commit->object.parsed = 1;
48 return commit;
49}
50/*
52 * Since we use get_tree_entry(), which does not put the read object into
53 * the object pool, we cannot rely on a == b.
54 */
55static int sha_eq(const unsigned char *a, const unsigned char *b)
56{
57 if (!a && !b)
58 return 2;
59 return a && b && hashcmp(a, b) == 0;
60}
61/*
63 * Since we want to write the index eventually, we cannot reuse the index
64 * for these (temporary) data.
65 */
66struct stage_data
67{
68 struct
69 {
70 unsigned mode;
71 unsigned char sha[20];
72 } stages[4];
73 unsigned processed:1;
74};
75static int show(struct merge_options *o, int v)
77{
78 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
79}
80static void flush_output(struct merge_options *o)
82{
83 if (o->obuf.len) {
84 fputs(o->obuf.buf, stdout);
85 strbuf_reset(&o->obuf);
86 }
87}
88static void output(struct merge_options *o, int v, const char *fmt, ...)
90{
91 int len;
92 va_list ap;
93 if (!show(o, v))
95 return;
96 strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
98 memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
99 strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
100 va_start(ap, fmt);
102 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
103 va_end(ap);
104 if (len < 0)
106 len = 0;
107 if (len >= strbuf_avail(&o->obuf)) {
108 strbuf_grow(&o->obuf, len + 2);
109 va_start(ap, fmt);
110 len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
111 va_end(ap);
112 if (len >= strbuf_avail(&o->obuf)) {
113 die("this should not happen, your snprintf is broken");
114 }
115 }
116 strbuf_setlen(&o->obuf, o->obuf.len + len);
117 strbuf_add(&o->obuf, "\n", 1);
118 if (!o->buffer_output)
119 flush_output(o);
120}
121static void output_commit_title(struct merge_options *o, struct commit *commit)
123{
124 int i;
125 flush_output(o);
126 for (i = o->call_depth; i--;)
127 fputs(" ", stdout);
128 if (commit->util)
129 printf("virtual %s\n", (char *)commit->util);
130 else {
131 printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
132 if (parse_commit(commit) != 0)
133 printf("(bad commit)\n");
134 else {
135 const char *s;
136 int len;
137 for (s = commit->buffer; *s; s++)
138 if (*s == '\n' && s[1] == '\n') {
139 s += 2;
140 break;
141 }
142 for (len = 0; s[len] && '\n' != s[len]; len++)
143 ; /* do nothing */
144 printf("%.*s\n", len, s);
145 }
146 }
147}
148static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
150 const char *path, int stage, int refresh, int options)
151{
152 struct cache_entry *ce;
153 ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
154 if (!ce)
155 return error("addinfo_cache failed for path '%s'", path);
156 return add_cache_entry(ce, options);
157}
158static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
160{
161 parse_tree(tree);
162 init_tree_desc(desc, tree->buffer, tree->size);
163}
164static int git_merge_trees(int index_only,
166 struct tree *common,
167 struct tree *head,
168 struct tree *merge)
169{
170 int rc;
171 struct tree_desc t[3];
172 struct unpack_trees_options opts;
173 memset(&opts, 0, sizeof(opts));
175 if (index_only)
176 opts.index_only = 1;
177 else
178 opts.update = 1;
179 opts.merge = 1;
180 opts.head_idx = 2;
181 opts.fn = threeway_merge;
182 opts.src_index = &the_index;
183 opts.dst_index = &the_index;
184 init_tree_desc_from_tree(t+0, common);
186 init_tree_desc_from_tree(t+1, head);
187 init_tree_desc_from_tree(t+2, merge);
188 rc = unpack_trees(3, t, &opts);
190 cache_tree_free(&active_cache_tree);
191 return rc;
192}
193struct tree *write_tree_from_memory(struct merge_options *o)
195{
196 struct tree *result = NULL;
197 if (unmerged_cache()) {
199 int i;
200 output(o, 0, "There are unmerged index entries:");
201 for (i = 0; i < active_nr; i++) {
202 struct cache_entry *ce = active_cache[i];
203 if (ce_stage(ce))
204 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
205 }
206 return NULL;
207 }
208 if (!active_cache_tree)
210 active_cache_tree = cache_tree();
211 if (!cache_tree_fully_valid(active_cache_tree) &&
213 cache_tree_update(active_cache_tree,
214 active_cache, active_nr, 0, 0) < 0)
215 die("error building trees");
216 result = lookup_tree(active_cache_tree->sha1);
218 return result;
220}
221static int save_files_dirs(const unsigned char *sha1,
223 const char *base, int baselen, const char *path,
224 unsigned int mode, int stage, void *context)
225{
226 int len = strlen(path);
227 char *newpath = xmalloc(baselen + len + 1);
228 struct merge_options *o = context;
229 memcpy(newpath, base, baselen);
231 memcpy(newpath + baselen, path, len);
232 newpath[baselen + len] = '\0';
233 if (S_ISDIR(mode))
235 string_list_insert(newpath, &o->current_directory_set);
236 else
237 string_list_insert(newpath, &o->current_file_set);
238 free(newpath);
239 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
241}
242static int get_files_dirs(struct merge_options *o, struct tree *tree)
244{
245 int n;
246 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
247 return 0;
248 n = o->current_file_set.nr + o->current_directory_set.nr;
249 return n;
250}
251/*
253 * Returns an index_entry instance which doesn't have to correspond to
254 * a real cache entry in Git's index.
255 */
256static struct stage_data *insert_stage_data(const char *path,
257 struct tree *o, struct tree *a, struct tree *b,
258 struct string_list *entries)
259{
260 struct string_list_item *item;
261 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
262 get_tree_entry(o->object.sha1, path,
263 e->stages[1].sha, &e->stages[1].mode);
264 get_tree_entry(a->object.sha1, path,
265 e->stages[2].sha, &e->stages[2].mode);
266 get_tree_entry(b->object.sha1, path,
267 e->stages[3].sha, &e->stages[3].mode);
268 item = string_list_insert(path, entries);
269 item->util = e;
270 return e;
271}
272/*
274 * Create a dictionary mapping file names to stage_data objects. The
275 * dictionary contains one entry for every path with a non-zero stage entry.
276 */
277static struct string_list *get_unmerged(void)
278{
279 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
280 int i;
281 unmerged->strdup_strings = 1;
283 for (i = 0; i < active_nr; i++) {
285 struct string_list_item *item;
286 struct stage_data *e;
287 struct cache_entry *ce = active_cache[i];
288 if (!ce_stage(ce))
289 continue;
290 item = string_list_lookup(ce->name, unmerged);
292 if (!item) {
293 item = string_list_insert(ce->name, unmerged);
294 item->util = xcalloc(1, sizeof(struct stage_data));
295 }
296 e = item->util;
297 e->stages[ce_stage(ce)].mode = ce->ce_mode;
298 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
299 }
300 return unmerged;
302}
303struct rename
305{
306 struct diff_filepair *pair;
307 struct stage_data *src_entry;
308 struct stage_data *dst_entry;
309 unsigned processed:1;
310};
311/*
313 * Get information of all renames which occurred between 'o_tree' and
314 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
315 * 'b_tree') to be able to associate the correct cache entries with
316 * the rename information. 'tree' is always equal to either a_tree or b_tree.
317 */
318static struct string_list *get_renames(struct merge_options *o,
319 struct tree *tree,
320 struct tree *o_tree,
321 struct tree *a_tree,
322 struct tree *b_tree,
323 struct string_list *entries)
324{
325 int i;
326 struct string_list *renames;
327 struct diff_options opts;
328 renames = xcalloc(1, sizeof(struct string_list));
330 diff_setup(&opts);
331 DIFF_OPT_SET(&opts, RECURSIVE);
332 opts.detect_rename = DIFF_DETECT_RENAME;
333 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
334 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
335 500;
336 opts.warn_on_too_large_rename = 1;
337 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
338 if (diff_setup_done(&opts) < 0)
339 die("diff setup failed");
340 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
341 diffcore_std(&opts);
342 for (i = 0; i < diff_queued_diff.nr; ++i) {
343 struct string_list_item *item;
344 struct rename *re;
345 struct diff_filepair *pair = diff_queued_diff.queue[i];
346 if (pair->status != 'R') {
347 diff_free_filepair(pair);
348 continue;
349 }
350 re = xmalloc(sizeof(*re));
351 re->processed = 0;
352 re->pair = pair;
353 item = string_list_lookup(re->pair->one->path, entries);
354 if (!item)
355 re->src_entry = insert_stage_data(re->pair->one->path,
356 o_tree, a_tree, b_tree, entries);
357 else
358 re->src_entry = item->util;
359 item = string_list_lookup(re->pair->two->path, entries);
361 if (!item)
362 re->dst_entry = insert_stage_data(re->pair->two->path,
363 o_tree, a_tree, b_tree, entries);
364 else
365 re->dst_entry = item->util;
366 item = string_list_insert(pair->one->path, renames);
367 item->util = re;
368 }
369 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
370 diff_queued_diff.nr = 0;
371 diff_flush(&opts);
372 return renames;
373}
374static int update_stages(const char *path, struct diff_filespec *o,
376 struct diff_filespec *a, struct diff_filespec *b,
377 int clear)
378{
379 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
380 if (clear)
381 if (remove_file_from_cache(path))
382 return -1;
383 if (o)
384 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
385 return -1;
386 if (a)
387 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
388 return -1;
389 if (b)
390 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
391 return -1;
392 return 0;
393}
394static int remove_file(struct merge_options *o, int clean,
396 const char *path, int no_wd)
397{
398 int update_cache = o->call_depth || clean;
399 int update_working_directory = !o->call_depth && !no_wd;
400 if (update_cache) {
402 if (remove_file_from_cache(path))
403 return -1;
404 }
405 if (update_working_directory) {
406 if (remove_path(path) && errno != ENOENT)
407 return -1;
408 }
409 return 0;
410}
411static char *unique_path(struct merge_options *o, const char *path, const char *branch)
413{
414 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
415 int suffix = 0;
416 struct stat st;
417 char *p = newpath + strlen(path);
418 strcpy(newpath, path);
419 *(p++) = '~';
420 strcpy(p, branch);
421 for (; *p; ++p)
422 if ('/' == *p)
423 *p = '_';
424 while (string_list_has_string(&o->current_file_set, newpath) ||
425 string_list_has_string(&o->current_directory_set, newpath) ||
426 lstat(newpath, &st) == 0)
427 sprintf(p, "_%d", suffix++);
428 string_list_insert(newpath, &o->current_file_set);
430 return newpath;
431}
432static void flush_buffer(int fd, const char *buf, unsigned long size)
434{
435 while (size > 0) {
436 long ret = write_in_full(fd, buf, size);
437 if (ret < 0) {
438 /* Ignore epipe */
439 if (errno == EPIPE)
440 break;
441 die_errno("merge-recursive");
442 } else if (!ret) {
443 die("merge-recursive: disk full?");
444 }
445 size -= ret;
446 buf += ret;
447 }
448}
449static int would_lose_untracked(const char *path)
451{
452 int pos = cache_name_pos(path, strlen(path));
453 if (pos < 0)
455 pos = -1 - pos;
456 while (pos < active_nr &&
457 !strcmp(path, active_cache[pos]->name)) {
458 /*
459 * If stage #0, it is definitely tracked.
460 * If it has stage #2 then it was tracked
461 * before this merge started. All other
462 * cases the path was not tracked.
463 */
464 switch (ce_stage(active_cache[pos])) {
465 case 0:
466 case 2:
467 return 0;
468 }
469 pos++;
470 }
471 return file_exists(path);
472}
473static int make_room_for_path(const char *path)
475{
476 int status;
477 const char *msg = "failed to create path '%s'%s";
478 status = safe_create_leading_directories_const(path);
480 if (status) {
481 if (status == -3) {
482 /* something else exists */
483 error(msg, path, ": perhaps a D/F conflict?");
484 return -1;
485 }
486 die(msg, path, "");
487 }
488 /*
490 * Do not unlink a file in the work tree if we are not
491 * tracking it.
492 */
493 if (would_lose_untracked(path))
494 return error("refusing to lose untracked file at '%s'",
495 path);
496 /* Successful unlink is good.. */
498 if (!unlink(path))
499 return 0;
500 /* .. and so is no existing file */
501 if (errno == ENOENT)
502 return 0;
503 /* .. but not some other error (who really cares what?) */
504 return error(msg, path, ": perhaps a D/F conflict?");
505}
506static void update_file_flags(struct merge_options *o,
508 const unsigned char *sha,
509 unsigned mode,
510 const char *path,
511 int update_cache,
512 int update_wd)
513{
514 if (o->call_depth)
515 update_wd = 0;
516 if (update_wd) {
518 enum object_type type;
519 void *buf;
520 unsigned long size;
521 if (S_ISGITLINK(mode))
523 /*
524 * We may later decide to recursively descend into
525 * the submodule directory and update its index
526 * and/or work tree, but we do not do that now.
527 */
528 goto update_index;
529 buf = read_sha1_file(sha, &type, &size);
531 if (!buf)
532 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
533 if (type != OBJ_BLOB)
534 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
535 if (S_ISREG(mode)) {
536 struct strbuf strbuf = STRBUF_INIT;
537 if (convert_to_working_tree(path, buf, size, &strbuf)) {
538 free(buf);
539 size = strbuf.len;
540 buf = strbuf_detach(&strbuf, NULL);
541 }
542 }
543 if (make_room_for_path(path) < 0) {
545 update_wd = 0;
546 free(buf);
547 goto update_index;
548 }
549 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
550 int fd;
551 if (mode & 0100)
552 mode = 0777;
553 else
554 mode = 0666;
555 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
556 if (fd < 0)
557 die_errno("failed to open '%s'", path);
558 flush_buffer(fd, buf, size);
559 close(fd);
560 } else if (S_ISLNK(mode)) {
561 char *lnk = xmemdupz(buf, size);
562 safe_create_leading_directories_const(path);
563 unlink(path);
564 if (symlink(lnk, path))
565 die_errno("failed to symlink '%s'", path);
566 free(lnk);
567 } else
568 die("do not know what to do with %06o %s '%s'",
569 mode, sha1_to_hex(sha), path);
570 free(buf);
571 }
572 update_index:
573 if (update_cache)
574 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
575}
576static void update_file(struct merge_options *o,
578 int clean,
579 const unsigned char *sha,
580 unsigned mode,
581 const char *path)
582{
583 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
584}
585/* Low level file merging, update and removal */
587struct merge_file_info
589{
590 unsigned char sha[20];
591 unsigned mode;
592 unsigned clean:1,
593 merge:1;
594};
595static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
597{
598 unsigned long size;
599 enum object_type type;
600 if (!hashcmp(sha1, null_sha1)) {
602 mm->ptr = xstrdup("");
603 mm->size = 0;
604 return;
605 }
606 mm->ptr = read_sha1_file(sha1, &type, &size);
608 if (!mm->ptr || type != OBJ_BLOB)
609 die("unable to read blob object %s", sha1_to_hex(sha1));
610 mm->size = size;
611}
612static int merge_3way(struct merge_options *o,
614 mmbuffer_t *result_buf,
615 struct diff_filespec *one,
616 struct diff_filespec *a,
617 struct diff_filespec *b,
618 const char *branch1,
619 const char *branch2)
620{
621 mmfile_t orig, src1, src2;
622 char *name1, *name2;
623 int merge_status;
624 if (strcmp(a->path, b->path)) {
626 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
627 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
628 } else {
629 name1 = xstrdup(mkpath("%s", branch1));
630 name2 = xstrdup(mkpath("%s", branch2));
631 }
632 fill_mm(one->sha1, &orig);
634 fill_mm(a->sha1, &src1);
635 fill_mm(b->sha1, &src2);
636 merge_status = ll_merge(result_buf, a->path, &orig,
638 &src1, name1, &src2, name2,
639 o->call_depth);
640 free(name1);
642 free(name2);
643 free(orig.ptr);
644 free(src1.ptr);
645 free(src2.ptr);
646 return merge_status;
647}
648static struct merge_file_info merge_file(struct merge_options *o,
650 struct diff_filespec *one,
651 struct diff_filespec *a,
652 struct diff_filespec *b,
653 const char *branch1,
654 const char *branch2)
655{
656 struct merge_file_info result;
657 result.merge = 0;
658 result.clean = 1;
659 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
661 result.clean = 0;
662 if (S_ISREG(a->mode)) {
663 result.mode = a->mode;
664 hashcpy(result.sha, a->sha1);
665 } else {
666 result.mode = b->mode;
667 hashcpy(result.sha, b->sha1);
668 }
669 } else {
670 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
671 result.merge = 1;
672 /*
674 * Merge modes
675 */
676 if (a->mode == b->mode || a->mode == one->mode)
677 result.mode = b->mode;
678 else {
679 result.mode = a->mode;
680 if (b->mode != one->mode) {
681 result.clean = 0;
682 result.merge = 1;
683 }
684 }
685 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
687 hashcpy(result.sha, b->sha1);
688 else if (sha_eq(b->sha1, one->sha1))
689 hashcpy(result.sha, a->sha1);
690 else if (S_ISREG(a->mode)) {
691 mmbuffer_t result_buf;
692 int merge_status;
693 merge_status = merge_3way(o, &result_buf, one, a, b,
695 branch1, branch2);
696 if ((merge_status < 0) || !result_buf.ptr)
698 die("Failed to execute internal merge");
699 if (write_sha1_file(result_buf.ptr, result_buf.size,
701 blob_type, result.sha))
702 die("Unable to add %s to database",
703 a->path);
704 free(result_buf.ptr);
706 result.clean = (merge_status == 0);
707 } else if (S_ISGITLINK(a->mode)) {
708 result.clean = 0;
709 hashcpy(result.sha, a->sha1);
710 } else if (S_ISLNK(a->mode)) {
711 hashcpy(result.sha, a->sha1);
712 if (!sha_eq(a->sha1, b->sha1))
714 result.clean = 0;
715 } else {
716 die("unsupported object type in the tree");
717 }
718 }
719 return result;
721}
722static void conflict_rename_rename(struct merge_options *o,
724 struct rename *ren1,
725 const char *branch1,
726 struct rename *ren2,
727 const char *branch2)
728{
729 char *del[2];
730 int delp = 0;
731 const char *ren1_dst = ren1->pair->two->path;
732 const char *ren2_dst = ren2->pair->two->path;
733 const char *dst_name1 = ren1_dst;
734 const char *dst_name2 = ren2_dst;
735 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
736 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
737 output(o, 1, "%s is a directory in %s adding as %s instead",
738 ren1_dst, branch2, dst_name1);
739 remove_file(o, 0, ren1_dst, 0);
740 }
741 if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
742 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
743 output(o, 1, "%s is a directory in %s adding as %s instead",
744 ren2_dst, branch1, dst_name2);
745 remove_file(o, 0, ren2_dst, 0);
746 }
747 if (o->call_depth) {
748 remove_file_from_cache(dst_name1);
749 remove_file_from_cache(dst_name2);
750 /*
751 * Uncomment to leave the conflicting names in the resulting tree
752 *
753 * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
754 * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
755 */
756 } else {
757 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
758 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
759 }
760 while (delp--)
761 free(del[delp]);
762}
763static void conflict_rename_dir(struct merge_options *o,
765 struct rename *ren1,
766 const char *branch1)
767{
768 char *new_path = unique_path(o, ren1->pair->two->path, branch1);
769 output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
770 remove_file(o, 0, ren1->pair->two->path, 0);
771 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
772 free(new_path);
773}
774static void conflict_rename_rename_2(struct merge_options *o,
776 struct rename *ren1,
777 const char *branch1,
778 struct rename *ren2,
779 const char *branch2)
780{
781 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
782 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
783 output(o, 1, "Renaming %s to %s and %s to %s instead",
784 ren1->pair->one->path, new_path1,
785 ren2->pair->one->path, new_path2);
786 remove_file(o, 0, ren1->pair->two->path, 0);
787 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
788 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
789 free(new_path2);
790 free(new_path1);
791}
792static int process_renames(struct merge_options *o,
794 struct string_list *a_renames,
795 struct string_list *b_renames)
796{
797 int clean_merge = 1, i, j;
798 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
799 const struct rename *sre;
800 for (i = 0; i < a_renames->nr; i++) {
802 sre = a_renames->items[i].util;
803 string_list_insert(sre->pair->two->path, &a_by_dst)->util
804 = sre->dst_entry;
805 }
806 for (i = 0; i < b_renames->nr; i++) {
807 sre = b_renames->items[i].util;
808 string_list_insert(sre->pair->two->path, &b_by_dst)->util
809 = sre->dst_entry;
810 }
811 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
813 char *src;
814 struct string_list *renames1, *renames2Dst;
815 struct rename *ren1 = NULL, *ren2 = NULL;
816 const char *branch1, *branch2;
817 const char *ren1_src, *ren1_dst;
818 if (i >= a_renames->nr) {
820 ren2 = b_renames->items[j++].util;
821 } else if (j >= b_renames->nr) {
822 ren1 = a_renames->items[i++].util;
823 } else {
824 int compare = strcmp(a_renames->items[i].string,
825 b_renames->items[j].string);
826 if (compare <= 0)
827 ren1 = a_renames->items[i++].util;
828 if (compare >= 0)
829 ren2 = b_renames->items[j++].util;
830 }
831 /* TODO: refactor, so that 1/2 are not needed */
833 if (ren1) {
834 renames1 = a_renames;
835 renames2Dst = &b_by_dst;
836 branch1 = o->branch1;
837 branch2 = o->branch2;
838 } else {
839 struct rename *tmp;
840 renames1 = b_renames;
841 renames2Dst = &a_by_dst;
842 branch1 = o->branch2;
843 branch2 = o->branch1;
844 tmp = ren2;
845 ren2 = ren1;
846 ren1 = tmp;
847 }
848 src = ren1->pair->one->path;
849 ren1->dst_entry->processed = 1;
851 ren1->src_entry->processed = 1;
852 if (ren1->processed)
854 continue;
855 ren1->processed = 1;
856 ren1_src = ren1->pair->one->path;
858 ren1_dst = ren1->pair->two->path;
859 if (ren2) {
861 const char *ren2_src = ren2->pair->one->path;
862 const char *ren2_dst = ren2->pair->two->path;
863 /* Renamed in 1 and renamed in 2 */
864 if (strcmp(ren1_src, ren2_src) != 0)
865 die("ren1.src != ren2.src");
866 ren2->dst_entry->processed = 1;
867 ren2->processed = 1;
868 if (strcmp(ren1_dst, ren2_dst) != 0) {
869 clean_merge = 0;
870 output(o, 1, "CONFLICT (rename/rename): "
871 "Rename \"%s\"->\"%s\" in branch \"%s\" "
872 "rename \"%s\"->\"%s\" in \"%s\"%s",
873 src, ren1_dst, branch1,
874 src, ren2_dst, branch2,
875 o->call_depth ? " (left unresolved)": "");
876 if (o->call_depth) {
877 remove_file_from_cache(src);
878 update_file(o, 0, ren1->pair->one->sha1,
879 ren1->pair->one->mode, src);
880 }
881 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
882 } else {
883 struct merge_file_info mfi;
884 remove_file(o, 1, ren1_src, 1);
885 mfi = merge_file(o,
886 ren1->pair->one,
887 ren1->pair->two,
888 ren2->pair->two,
889 branch1,
890 branch2);
891 if (mfi.merge || !mfi.clean)
892 output(o, 1, "Renaming %s->%s", src, ren1_dst);
893 if (mfi.merge)
895 output(o, 2, "Auto-merging %s", ren1_dst);
896 if (!mfi.clean) {
898 output(o, 1, "CONFLICT (content): merge conflict in %s",
899 ren1_dst);
900 clean_merge = 0;
901 if (!o->call_depth)
903 update_stages(ren1_dst,
904 ren1->pair->one,
905 ren1->pair->two,
906 ren2->pair->two,
907 1 /* clear */);
908 }
909 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
910 }
911 } else {
912 /* Renamed in 1, maybe changed in 2 */
913 struct string_list_item *item;
914 /* we only use sha1 and mode of these */
915 struct diff_filespec src_other, dst_other;
916 int try_merge, stage = a_renames == renames1 ? 3: 2;
917 remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
919 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
921 src_other.mode = ren1->src_entry->stages[stage].mode;
922 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
923 dst_other.mode = ren1->dst_entry->stages[stage].mode;
924 try_merge = 0;
926 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
928 clean_merge = 0;
929 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
930 " directory %s added in %s",
931 ren1_src, ren1_dst, branch1,
932 ren1_dst, branch2);
933 conflict_rename_dir(o, ren1, branch1);
934 } else if (sha_eq(src_other.sha1, null_sha1)) {
935 clean_merge = 0;
936 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
937 "and deleted in %s",
938 ren1_src, ren1_dst, branch1,
939 branch2);
940 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
941 if (!o->call_depth)
942 update_stages(ren1_dst, NULL,
943 branch1 == o->branch1 ?
944 ren1->pair->two : NULL,
945 branch1 == o->branch1 ?
946 NULL : ren1->pair->two, 1);
947 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
948 const char *new_path;
949 clean_merge = 0;
950 try_merge = 1;
951 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
952 "%s added in %s",
953 ren1_src, ren1_dst, branch1,
954 ren1_dst, branch2);
955 if (o->call_depth) {
956 struct merge_file_info mfi;
957 struct diff_filespec one, a, b;
958 one.path = a.path = b.path =
960 (char *)ren1_dst;
961 hashcpy(one.sha1, null_sha1);
962 one.mode = 0;
963 hashcpy(a.sha1, ren1->pair->two->sha1);
964 a.mode = ren1->pair->two->mode;
965 hashcpy(b.sha1, dst_other.sha1);
966 b.mode = dst_other.mode;
967 mfi = merge_file(o, &one, &a, &b,
968 branch1,
969 branch2);
970 output(o, 1, "Adding merged %s", ren1_dst);
971 update_file(o, 0,
972 mfi.sha,
973 mfi.mode,
974 ren1_dst);
975 } else {
976 new_path = unique_path(o, ren1_dst, branch2);
977 output(o, 1, "Adding as %s instead", new_path);
978 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
979 }
980 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
981 ren2 = item->util;
982 clean_merge = 0;
983 ren2->processed = 1;
984 output(o, 1, "CONFLICT (rename/rename): "
985 "Rename %s->%s in %s. "
986 "Rename %s->%s in %s",
987 ren1_src, ren1_dst, branch1,
988 ren2->pair->one->path, ren2->pair->two->path, branch2);
989 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
990 } else
991 try_merge = 1;
992 if (try_merge) {
994 struct diff_filespec *one, *a, *b;
995 struct merge_file_info mfi;
996 src_other.path = (char *)ren1_src;
997 one = ren1->pair->one;
999 if (a_renames == renames1) {
1000 a = ren1->pair->two;
1001 b = &src_other;
1002 } else {
1003 b = ren1->pair->two;
1004 a = &src_other;
1005 }
1006 mfi = merge_file(o, one, a, b,
1007 o->branch1, o->branch2);
1008 if (mfi.clean &&
1010 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1011 mfi.mode == ren1->pair->two->mode)
1012 /*
1013 * This messaged is part of
1014 * t6022 test. If you change
1015 * it update the test too.
1016 */
1017 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
1018 else {
1019 if (mfi.merge || !mfi.clean)
1020 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
1021 if (mfi.merge)
1022 output(o, 2, "Auto-merging %s", ren1_dst);
1023 if (!mfi.clean) {
1024 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
1025 ren1_dst);
1026 clean_merge = 0;
1027 if (!o->call_depth)
1029 update_stages(ren1_dst,
1030 one, a, b, 1);
1031 }
1032 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1033 }
1034 }
1035 }
1036 }
1037 string_list_clear(&a_by_dst, 0);
1038 string_list_clear(&b_by_dst, 0);
1039 return clean_merge;
1041}
1042static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1044{
1045 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1046}
1047/* Per entry merge function */
1049static int process_entry(struct merge_options *o,
1050 const char *path, struct stage_data *entry)
1051{
1052 /*
1053 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1054 print_index_entry("\tpath: ", entry);
1055 */
1056 int clean_merge = 1;
1057 unsigned o_mode = entry->stages[1].mode;
1058 unsigned a_mode = entry->stages[2].mode;
1059 unsigned b_mode = entry->stages[3].mode;
1060 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1061 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1062 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1063 if (o_sha && (!a_sha || !b_sha)) {
1065 /* Case A: Deleted in one */
1066 if ((!a_sha && !b_sha) ||
1067 (sha_eq(a_sha, o_sha) && !b_sha) ||
1068 (!a_sha && sha_eq(b_sha, o_sha))) {
1069 /* Deleted in both or deleted in one and
1070 * unchanged in the other */
1071 if (a_sha)
1072 output(o, 2, "Removing %s", path);
1073 /* do not touch working file if it did not exist */
1074 remove_file(o, 1, path, !a_sha);
1075 } else {
1076 /* Deleted in one and changed in the other */
1077 clean_merge = 0;
1078 if (!a_sha) {
1079 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1080 "and modified in %s. Version %s of %s left in tree.",
1081 path, o->branch1,
1082 o->branch2, o->branch2, path);
1083 update_file(o, 0, b_sha, b_mode, path);
1084 } else {
1085 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1086 "and modified in %s. Version %s of %s left in tree.",
1087 path, o->branch2,
1088 o->branch1, o->branch1, path);
1089 update_file(o, 0, a_sha, a_mode, path);
1090 }
1091 }
1092 } else if ((!o_sha && a_sha && !b_sha) ||
1094 (!o_sha && !a_sha && b_sha)) {
1095 /* Case B: Added in one. */
1096 const char *add_branch;
1097 const char *other_branch;
1098 unsigned mode;
1099 const unsigned char *sha;
1100 const char *conf;
1101 if (a_sha) {
1103 add_branch = o->branch1;
1104 other_branch = o->branch2;
1105 mode = a_mode;
1106 sha = a_sha;
1107 conf = "file/directory";
1108 } else {
1109 add_branch = o->branch2;
1110 other_branch = o->branch1;
1111 mode = b_mode;
1112 sha = b_sha;
1113 conf = "directory/file";
1114 }
1115 if (string_list_has_string(&o->current_directory_set, path)) {
1116 const char *new_path = unique_path(o, path, add_branch);
1117 clean_merge = 0;
1118 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1119 "Adding %s as %s",
1120 conf, path, other_branch, path, new_path);
1121 remove_file(o, 0, path, 0);
1122 update_file(o, 0, sha, mode, new_path);
1123 } else {
1124 output(o, 2, "Adding %s", path);
1125 update_file(o, 1, sha, mode, path);
1126 }
1127 } else if (a_sha && b_sha) {
1128 /* Case C: Added in both (check for same permissions) and */
1129 /* case D: Modified in both, but differently. */
1130 const char *reason = "content";
1131 struct merge_file_info mfi;
1132 struct diff_filespec one, a, b;
1133 if (!o_sha) {
1135 reason = "add/add";
1136 o_sha = (unsigned char *)null_sha1;
1137 }
1138 output(o, 2, "Auto-merging %s", path);
1139 one.path = a.path = b.path = (char *)path;
1140 hashcpy(one.sha1, o_sha);
1141 one.mode = o_mode;
1142 hashcpy(a.sha1, a_sha);
1143 a.mode = a_mode;
1144 hashcpy(b.sha1, b_sha);
1145 b.mode = b_mode;
1146 mfi = merge_file(o, &one, &a, &b,
1148 o->branch1, o->branch2);
1149 clean_merge = mfi.clean;
1151 if (!mfi.clean) {
1152 if (S_ISGITLINK(mfi.mode))
1153 reason = "submodule";
1154 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1155 reason, path);
1156 }
1157 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1158 } else if (!o_sha && !a_sha && !b_sha) {
1159 /*
1160 * this entry was deleted altogether. a_mode == 0 means
1161 * we had that path and want to actively remove it.
1162 */
1163 remove_file(o, 1, path, !a_mode);
1164 } else
1165 die("Fatal merge failure, shouldn't happen.");
1166 return clean_merge;
1168}
1169int merge_trees(struct merge_options *o,
1171 struct tree *head,
1172 struct tree *merge,
1173 struct tree *common,
1174 struct tree **result)
1175{
1176 int code, clean;
1177 if (o->subtree_merge) {
1179 merge = shift_tree_object(head, merge);
1180 common = shift_tree_object(head, common);
1181 }
1182 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1184 output(o, 0, "Already uptodate!");
1185 *result = head;
1186 return 1;
1187 }
1188 code = git_merge_trees(o->call_depth, common, head, merge);
1190 if (code != 0)
1192 die("merging of trees %s and %s failed",
1193 sha1_to_hex(head->object.sha1),
1194 sha1_to_hex(merge->object.sha1));
1195 if (unmerged_cache()) {
1197 struct string_list *entries, *re_head, *re_merge;
1198 int i;
1199 string_list_clear(&o->current_file_set, 1);
1200 string_list_clear(&o->current_directory_set, 1);
1201 get_files_dirs(o, head);
1202 get_files_dirs(o, merge);
1203 entries = get_unmerged();
1205 re_head = get_renames(o, head, common, head, merge, entries);
1206 re_merge = get_renames(o, merge, common, head, merge, entries);
1207 clean = process_renames(o, re_head, re_merge);
1208 for (i = 0; i < entries->nr; i++) {
1209 const char *path = entries->items[i].string;
1210 struct stage_data *e = entries->items[i].util;
1211 if (!e->processed
1212 && !process_entry(o, path, e))
1213 clean = 0;
1214 }
1215 string_list_clear(re_merge, 0);
1217 string_list_clear(re_head, 0);
1218 string_list_clear(entries, 1);
1219 }
1221 else
1222 clean = 1;
1223 if (o->call_depth)
1225 *result = write_tree_from_memory(o);
1226 return clean;
1228}
1229static struct commit_list *reverse_commit_list(struct commit_list *list)
1231{
1232 struct commit_list *next = NULL, *current, *backup;
1233 for (current = list; current; current = backup) {
1234 backup = current->next;
1235 current->next = next;
1236 next = current;
1237 }
1238 return next;
1239}
1240/*
1242 * Merge the commits h1 and h2, return the resulting virtual
1243 * commit object and a flag indicating the cleanness of the merge.
1244 */
1245int merge_recursive(struct merge_options *o,
1246 struct commit *h1,
1247 struct commit *h2,
1248 struct commit_list *ca,
1249 struct commit **result)
1250{
1251 struct commit_list *iter;
1252 struct commit *merged_common_ancestors;
1253 struct tree *mrtree = mrtree;
1254 int clean;
1255 if (show(o, 4)) {
1257 output(o, 4, "Merging:");
1258 output_commit_title(o, h1);
1259 output_commit_title(o, h2);
1260 }
1261 if (!ca) {
1263 ca = get_merge_bases(h1, h2, 1);
1264 ca = reverse_commit_list(ca);
1265 }
1266 if (show(o, 5)) {
1268 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1269 for (iter = ca; iter; iter = iter->next)
1270 output_commit_title(o, iter->item);
1271 }
1272 merged_common_ancestors = pop_commit(&ca);
1274 if (merged_common_ancestors == NULL) {
1275 /* if there is no common ancestor, make an empty tree */
1276 struct tree *tree = xcalloc(1, sizeof(struct tree));
1277 tree->object.parsed = 1;
1279 tree->object.type = OBJ_TREE;
1280 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1281 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1282 }
1283 for (iter = ca; iter; iter = iter->next) {
1285 const char *saved_b1, *saved_b2;
1286 o->call_depth++;
1287 /*
1288 * When the merge fails, the result contains files
1289 * with conflict markers. The cleanness flag is
1290 * ignored, it was never actually used, as result of
1291 * merge_trees has always overwritten it: the committed
1292 * "conflicts" were already resolved.
1293 */
1294 discard_cache();
1295 saved_b1 = o->branch1;
1296 saved_b2 = o->branch2;
1297 o->branch1 = "Temporary merge branch 1";
1298 o->branch2 = "Temporary merge branch 2";
1299 merge_recursive(o, merged_common_ancestors, iter->item,
1300 NULL, &merged_common_ancestors);
1301 o->branch1 = saved_b1;
1302 o->branch2 = saved_b2;
1303 o->call_depth--;
1304 if (!merged_common_ancestors)
1306 die("merge returned no commit");
1307 }
1308 discard_cache();
1310 if (!o->call_depth)
1311 read_cache();
1312 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1314 &mrtree);
1315 if (o->call_depth) {
1317 *result = make_virtual_commit(mrtree, "merged tree");
1318 commit_list_insert(h1, &(*result)->parents);
1319 commit_list_insert(h2, &(*result)->parents->next);
1320 }
1321 flush_output(o);
1322 return clean;
1323}
1324static struct commit *get_ref(const unsigned char *sha1, const char *name)
1326{
1327 struct object *object;
1328 object = deref_tag(parse_object(sha1), name, strlen(name));
1330 if (!object)
1331 return NULL;
1332 if (object->type == OBJ_TREE)
1333 return make_virtual_commit((struct tree*)object, name);
1334 if (object->type != OBJ_COMMIT)
1335 return NULL;
1336 if (parse_commit((struct commit *)object))
1337 return NULL;
1338 return (struct commit *)object;
1339}
1340int merge_recursive_generic(struct merge_options *o,
1342 const unsigned char *head,
1343 const unsigned char *merge,
1344 int num_base_list,
1345 const unsigned char **base_list,
1346 struct commit **result)
1347{
1348 int clean, index_fd;
1349 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1350 struct commit *head_commit = get_ref(head, o->branch1);
1351 struct commit *next_commit = get_ref(merge, o->branch2);
1352 struct commit_list *ca = NULL;
1353 if (base_list) {
1355 int i;
1356 for (i = 0; i < num_base_list; ++i) {
1357 struct commit *base;
1358 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1359 return error("Could not parse object '%s'",
1360 sha1_to_hex(base_list[i]));
1361 commit_list_insert(base, &ca);
1362 }
1363 }
1364 index_fd = hold_locked_index(lock, 1);
1366 clean = merge_recursive(o, head_commit, next_commit, ca,
1367 result);
1368 if (active_cache_changed &&
1369 (write_cache(index_fd, active_cache, active_nr) ||
1370 commit_locked_index(lock)))
1371 return error("Unable to write index.");
1372 return clean ? 0 : 1;
1374}
1375static int merge_recursive_config(const char *var, const char *value, void *cb)
1377{
1378 struct merge_options *o = cb;
1379 if (!strcasecmp(var, "merge.verbosity")) {
1380 o->verbosity = git_config_int(var, value);
1381 return 0;
1382 }
1383 if (!strcasecmp(var, "diff.renamelimit")) {
1384 o->diff_rename_limit = git_config_int(var, value);
1385 return 0;
1386 }
1387 if (!strcasecmp(var, "merge.renamelimit")) {
1388 o->merge_rename_limit = git_config_int(var, value);
1389 return 0;
1390 }
1391 return git_xmerge_config(var, value, cb);
1392}
1393void init_merge_options(struct merge_options *o)
1395{
1396 memset(o, 0, sizeof(struct merge_options));
1397 o->verbosity = 2;
1398 o->buffer_output = 1;
1399 o->diff_rename_limit = -1;
1400 o->merge_rename_limit = -1;
1401 git_config(merge_recursive_config, o);
1402 if (getenv("GIT_MERGE_VERBOSITY"))
1403 o->verbosity =
1404 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1405 if (o->verbosity >= 5)
1406 o->buffer_output = 0;
1407 strbuf_init(&o->obuf, 0);
1408 memset(&o->current_file_set, 0, sizeof(struct string_list));
1409 o->current_file_set.strdup_strings = 1;
1410 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1411 o->current_directory_set.strdup_strings = 1;
1412}