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 static const struct unpack_trees_error_msgs msgs = {
174 /* would_overwrite */
175 "Your local changes to '%s' would be overwritten by merge. Aborting.",
176 /* not_uptodate_file */
177 "Your local changes to '%s' would be overwritten by merge. Aborting.",
178 /* not_uptodate_dir */
179 "Updating '%s' would lose untracked files in it. Aborting.",
180 /* would_lose_untracked */
181 "Untracked working tree file '%s' would be %s by merge. Aborting",
182 /* bind_overlap -- will not happen here */
183 NULL,
184 };
185 memset(&opts, 0, sizeof(opts));
187 if (index_only)
188 opts.index_only = 1;
189 else
190 opts.update = 1;
191 opts.merge = 1;
192 opts.head_idx = 2;
193 opts.fn = threeway_merge;
194 opts.src_index = &the_index;
195 opts.dst_index = &the_index;
196 opts.msgs = msgs;
197 init_tree_desc_from_tree(t+0, common);
199 init_tree_desc_from_tree(t+1, head);
200 init_tree_desc_from_tree(t+2, merge);
201 rc = unpack_trees(3, t, &opts);
203 cache_tree_free(&active_cache_tree);
204 return rc;
205}
206struct tree *write_tree_from_memory(struct merge_options *o)
208{
209 struct tree *result = NULL;
210 if (unmerged_cache()) {
212 int i;
213 output(o, 0, "There are unmerged index entries:");
214 for (i = 0; i < active_nr; i++) {
215 struct cache_entry *ce = active_cache[i];
216 if (ce_stage(ce))
217 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
218 }
219 return NULL;
220 }
221 if (!active_cache_tree)
223 active_cache_tree = cache_tree();
224 if (!cache_tree_fully_valid(active_cache_tree) &&
226 cache_tree_update(active_cache_tree,
227 active_cache, active_nr, 0, 0) < 0)
228 die("error building trees");
229 result = lookup_tree(active_cache_tree->sha1);
231 return result;
233}
234static int save_files_dirs(const unsigned char *sha1,
236 const char *base, int baselen, const char *path,
237 unsigned int mode, int stage, void *context)
238{
239 int len = strlen(path);
240 char *newpath = xmalloc(baselen + len + 1);
241 struct merge_options *o = context;
242 memcpy(newpath, base, baselen);
244 memcpy(newpath + baselen, path, len);
245 newpath[baselen + len] = '\0';
246 if (S_ISDIR(mode))
248 string_list_insert(newpath, &o->current_directory_set);
249 else
250 string_list_insert(newpath, &o->current_file_set);
251 free(newpath);
252 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
254}
255static int get_files_dirs(struct merge_options *o, struct tree *tree)
257{
258 int n;
259 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
260 return 0;
261 n = o->current_file_set.nr + o->current_directory_set.nr;
262 return n;
263}
264/*
266 * Returns an index_entry instance which doesn't have to correspond to
267 * a real cache entry in Git's index.
268 */
269static struct stage_data *insert_stage_data(const char *path,
270 struct tree *o, struct tree *a, struct tree *b,
271 struct string_list *entries)
272{
273 struct string_list_item *item;
274 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
275 get_tree_entry(o->object.sha1, path,
276 e->stages[1].sha, &e->stages[1].mode);
277 get_tree_entry(a->object.sha1, path,
278 e->stages[2].sha, &e->stages[2].mode);
279 get_tree_entry(b->object.sha1, path,
280 e->stages[3].sha, &e->stages[3].mode);
281 item = string_list_insert(path, entries);
282 item->util = e;
283 return e;
284}
285/*
287 * Create a dictionary mapping file names to stage_data objects. The
288 * dictionary contains one entry for every path with a non-zero stage entry.
289 */
290static struct string_list *get_unmerged(void)
291{
292 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
293 int i;
294 unmerged->strdup_strings = 1;
296 for (i = 0; i < active_nr; i++) {
298 struct string_list_item *item;
299 struct stage_data *e;
300 struct cache_entry *ce = active_cache[i];
301 if (!ce_stage(ce))
302 continue;
303 item = string_list_lookup(ce->name, unmerged);
305 if (!item) {
306 item = string_list_insert(ce->name, unmerged);
307 item->util = xcalloc(1, sizeof(struct stage_data));
308 }
309 e = item->util;
310 e->stages[ce_stage(ce)].mode = ce->ce_mode;
311 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
312 }
313 return unmerged;
315}
316struct rename
318{
319 struct diff_filepair *pair;
320 struct stage_data *src_entry;
321 struct stage_data *dst_entry;
322 unsigned processed:1;
323};
324/*
326 * Get information of all renames which occurred between 'o_tree' and
327 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
328 * 'b_tree') to be able to associate the correct cache entries with
329 * the rename information. 'tree' is always equal to either a_tree or b_tree.
330 */
331static struct string_list *get_renames(struct merge_options *o,
332 struct tree *tree,
333 struct tree *o_tree,
334 struct tree *a_tree,
335 struct tree *b_tree,
336 struct string_list *entries)
337{
338 int i;
339 struct string_list *renames;
340 struct diff_options opts;
341 renames = xcalloc(1, sizeof(struct string_list));
343 diff_setup(&opts);
344 DIFF_OPT_SET(&opts, RECURSIVE);
345 opts.detect_rename = DIFF_DETECT_RENAME;
346 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
347 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
348 500;
349 opts.warn_on_too_large_rename = 1;
350 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
351 if (diff_setup_done(&opts) < 0)
352 die("diff setup failed");
353 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
354 diffcore_std(&opts);
355 for (i = 0; i < diff_queued_diff.nr; ++i) {
356 struct string_list_item *item;
357 struct rename *re;
358 struct diff_filepair *pair = diff_queued_diff.queue[i];
359 if (pair->status != 'R') {
360 diff_free_filepair(pair);
361 continue;
362 }
363 re = xmalloc(sizeof(*re));
364 re->processed = 0;
365 re->pair = pair;
366 item = string_list_lookup(re->pair->one->path, entries);
367 if (!item)
368 re->src_entry = insert_stage_data(re->pair->one->path,
369 o_tree, a_tree, b_tree, entries);
370 else
371 re->src_entry = item->util;
372 item = string_list_lookup(re->pair->two->path, entries);
374 if (!item)
375 re->dst_entry = insert_stage_data(re->pair->two->path,
376 o_tree, a_tree, b_tree, entries);
377 else
378 re->dst_entry = item->util;
379 item = string_list_insert(pair->one->path, renames);
380 item->util = re;
381 }
382 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
383 diff_queued_diff.nr = 0;
384 diff_flush(&opts);
385 return renames;
386}
387static int update_stages(const char *path, struct diff_filespec *o,
389 struct diff_filespec *a, struct diff_filespec *b,
390 int clear)
391{
392 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
393 if (clear)
394 if (remove_file_from_cache(path))
395 return -1;
396 if (o)
397 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
398 return -1;
399 if (a)
400 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
401 return -1;
402 if (b)
403 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
404 return -1;
405 return 0;
406}
407static int remove_file(struct merge_options *o, int clean,
409 const char *path, int no_wd)
410{
411 int update_cache = o->call_depth || clean;
412 int update_working_directory = !o->call_depth && !no_wd;
413 if (update_cache) {
415 if (remove_file_from_cache(path))
416 return -1;
417 }
418 if (update_working_directory) {
419 if (remove_path(path) && errno != ENOENT)
420 return -1;
421 }
422 return 0;
423}
424static char *unique_path(struct merge_options *o, const char *path, const char *branch)
426{
427 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
428 int suffix = 0;
429 struct stat st;
430 char *p = newpath + strlen(path);
431 strcpy(newpath, path);
432 *(p++) = '~';
433 strcpy(p, branch);
434 for (; *p; ++p)
435 if ('/' == *p)
436 *p = '_';
437 while (string_list_has_string(&o->current_file_set, newpath) ||
438 string_list_has_string(&o->current_directory_set, newpath) ||
439 lstat(newpath, &st) == 0)
440 sprintf(p, "_%d", suffix++);
441 string_list_insert(newpath, &o->current_file_set);
443 return newpath;
444}
445static void flush_buffer(int fd, const char *buf, unsigned long size)
447{
448 while (size > 0) {
449 long ret = write_in_full(fd, buf, size);
450 if (ret < 0) {
451 /* Ignore epipe */
452 if (errno == EPIPE)
453 break;
454 die_errno("merge-recursive");
455 } else if (!ret) {
456 die("merge-recursive: disk full?");
457 }
458 size -= ret;
459 buf += ret;
460 }
461}
462static int would_lose_untracked(const char *path)
464{
465 int pos = cache_name_pos(path, strlen(path));
466 if (pos < 0)
468 pos = -1 - pos;
469 while (pos < active_nr &&
470 !strcmp(path, active_cache[pos]->name)) {
471 /*
472 * If stage #0, it is definitely tracked.
473 * If it has stage #2 then it was tracked
474 * before this merge started. All other
475 * cases the path was not tracked.
476 */
477 switch (ce_stage(active_cache[pos])) {
478 case 0:
479 case 2:
480 return 0;
481 }
482 pos++;
483 }
484 return file_exists(path);
485}
486static int make_room_for_path(const char *path)
488{
489 int status;
490 const char *msg = "failed to create path '%s'%s";
491 status = safe_create_leading_directories_const(path);
493 if (status) {
494 if (status == -3) {
495 /* something else exists */
496 error(msg, path, ": perhaps a D/F conflict?");
497 return -1;
498 }
499 die(msg, path, "");
500 }
501 /*
503 * Do not unlink a file in the work tree if we are not
504 * tracking it.
505 */
506 if (would_lose_untracked(path))
507 return error("refusing to lose untracked file at '%s'",
508 path);
509 /* Successful unlink is good.. */
511 if (!unlink(path))
512 return 0;
513 /* .. and so is no existing file */
514 if (errno == ENOENT)
515 return 0;
516 /* .. but not some other error (who really cares what?) */
517 return error(msg, path, ": perhaps a D/F conflict?");
518}
519static void update_file_flags(struct merge_options *o,
521 const unsigned char *sha,
522 unsigned mode,
523 const char *path,
524 int update_cache,
525 int update_wd)
526{
527 if (o->call_depth)
528 update_wd = 0;
529 if (update_wd) {
531 enum object_type type;
532 void *buf;
533 unsigned long size;
534 if (S_ISGITLINK(mode))
536 /*
537 * We may later decide to recursively descend into
538 * the submodule directory and update its index
539 * and/or work tree, but we do not do that now.
540 */
541 goto update_index;
542 buf = read_sha1_file(sha, &type, &size);
544 if (!buf)
545 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
546 if (type != OBJ_BLOB)
547 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
548 if (S_ISREG(mode)) {
549 struct strbuf strbuf = STRBUF_INIT;
550 if (convert_to_working_tree(path, buf, size, &strbuf)) {
551 free(buf);
552 size = strbuf.len;
553 buf = strbuf_detach(&strbuf, NULL);
554 }
555 }
556 if (make_room_for_path(path) < 0) {
558 update_wd = 0;
559 free(buf);
560 goto update_index;
561 }
562 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
563 int fd;
564 if (mode & 0100)
565 mode = 0777;
566 else
567 mode = 0666;
568 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
569 if (fd < 0)
570 die_errno("failed to open '%s'", path);
571 flush_buffer(fd, buf, size);
572 close(fd);
573 } else if (S_ISLNK(mode)) {
574 char *lnk = xmemdupz(buf, size);
575 safe_create_leading_directories_const(path);
576 unlink(path);
577 if (symlink(lnk, path))
578 die_errno("failed to symlink '%s'", path);
579 free(lnk);
580 } else
581 die("do not know what to do with %06o %s '%s'",
582 mode, sha1_to_hex(sha), path);
583 free(buf);
584 }
585 update_index:
586 if (update_cache)
587 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
588}
589static void update_file(struct merge_options *o,
591 int clean,
592 const unsigned char *sha,
593 unsigned mode,
594 const char *path)
595{
596 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
597}
598/* Low level file merging, update and removal */
600struct merge_file_info
602{
603 unsigned char sha[20];
604 unsigned mode;
605 unsigned clean:1,
606 merge:1;
607};
608static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
610{
611 unsigned long size;
612 enum object_type type;
613 if (!hashcmp(sha1, null_sha1)) {
615 mm->ptr = xstrdup("");
616 mm->size = 0;
617 return;
618 }
619 mm->ptr = read_sha1_file(sha1, &type, &size);
621 if (!mm->ptr || type != OBJ_BLOB)
622 die("unable to read blob object %s", sha1_to_hex(sha1));
623 mm->size = size;
624}
625static int merge_3way(struct merge_options *o,
627 mmbuffer_t *result_buf,
628 struct diff_filespec *one,
629 struct diff_filespec *a,
630 struct diff_filespec *b,
631 const char *branch1,
632 const char *branch2)
633{
634 mmfile_t orig, src1, src2;
635 char *name1, *name2;
636 int merge_status;
637 if (strcmp(a->path, b->path)) {
639 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
640 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
641 } else {
642 name1 = xstrdup(mkpath("%s", branch1));
643 name2 = xstrdup(mkpath("%s", branch2));
644 }
645 fill_mm(one->sha1, &orig);
647 fill_mm(a->sha1, &src1);
648 fill_mm(b->sha1, &src2);
649 merge_status = ll_merge(result_buf, a->path, &orig,
651 &src1, name1, &src2, name2,
652 o->call_depth);
653 free(name1);
655 free(name2);
656 free(orig.ptr);
657 free(src1.ptr);
658 free(src2.ptr);
659 return merge_status;
660}
661static struct merge_file_info merge_file(struct merge_options *o,
663 struct diff_filespec *one,
664 struct diff_filespec *a,
665 struct diff_filespec *b,
666 const char *branch1,
667 const char *branch2)
668{
669 struct merge_file_info result;
670 result.merge = 0;
671 result.clean = 1;
672 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
674 result.clean = 0;
675 if (S_ISREG(a->mode)) {
676 result.mode = a->mode;
677 hashcpy(result.sha, a->sha1);
678 } else {
679 result.mode = b->mode;
680 hashcpy(result.sha, b->sha1);
681 }
682 } else {
683 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
684 result.merge = 1;
685 /*
687 * Merge modes
688 */
689 if (a->mode == b->mode || a->mode == one->mode)
690 result.mode = b->mode;
691 else {
692 result.mode = a->mode;
693 if (b->mode != one->mode) {
694 result.clean = 0;
695 result.merge = 1;
696 }
697 }
698 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
700 hashcpy(result.sha, b->sha1);
701 else if (sha_eq(b->sha1, one->sha1))
702 hashcpy(result.sha, a->sha1);
703 else if (S_ISREG(a->mode)) {
704 mmbuffer_t result_buf;
705 int merge_status;
706 merge_status = merge_3way(o, &result_buf, one, a, b,
708 branch1, branch2);
709 if ((merge_status < 0) || !result_buf.ptr)
711 die("Failed to execute internal merge");
712 if (write_sha1_file(result_buf.ptr, result_buf.size,
714 blob_type, result.sha))
715 die("Unable to add %s to database",
716 a->path);
717 free(result_buf.ptr);
719 result.clean = (merge_status == 0);
720 } else if (S_ISGITLINK(a->mode)) {
721 result.clean = 0;
722 hashcpy(result.sha, a->sha1);
723 } else if (S_ISLNK(a->mode)) {
724 hashcpy(result.sha, a->sha1);
725 if (!sha_eq(a->sha1, b->sha1))
727 result.clean = 0;
728 } else {
729 die("unsupported object type in the tree");
730 }
731 }
732 return result;
734}
735static void conflict_rename_rename(struct merge_options *o,
737 struct rename *ren1,
738 const char *branch1,
739 struct rename *ren2,
740 const char *branch2)
741{
742 char *del[2];
743 int delp = 0;
744 const char *ren1_dst = ren1->pair->two->path;
745 const char *ren2_dst = ren2->pair->two->path;
746 const char *dst_name1 = ren1_dst;
747 const char *dst_name2 = ren2_dst;
748 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
749 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
750 output(o, 1, "%s is a directory in %s adding as %s instead",
751 ren1_dst, branch2, dst_name1);
752 remove_file(o, 0, ren1_dst, 0);
753 }
754 if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
755 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
756 output(o, 1, "%s is a directory in %s adding as %s instead",
757 ren2_dst, branch1, dst_name2);
758 remove_file(o, 0, ren2_dst, 0);
759 }
760 if (o->call_depth) {
761 remove_file_from_cache(dst_name1);
762 remove_file_from_cache(dst_name2);
763 /*
764 * Uncomment to leave the conflicting names in the resulting tree
765 *
766 * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
767 * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
768 */
769 } else {
770 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
771 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
772 }
773 while (delp--)
774 free(del[delp]);
775}
776static void conflict_rename_dir(struct merge_options *o,
778 struct rename *ren1,
779 const char *branch1)
780{
781 char *new_path = unique_path(o, ren1->pair->two->path, branch1);
782 output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
783 remove_file(o, 0, ren1->pair->two->path, 0);
784 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
785 free(new_path);
786}
787static void conflict_rename_rename_2(struct merge_options *o,
789 struct rename *ren1,
790 const char *branch1,
791 struct rename *ren2,
792 const char *branch2)
793{
794 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
795 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
796 output(o, 1, "Renaming %s to %s and %s to %s instead",
797 ren1->pair->one->path, new_path1,
798 ren2->pair->one->path, new_path2);
799 remove_file(o, 0, ren1->pair->two->path, 0);
800 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
801 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
802 free(new_path2);
803 free(new_path1);
804}
805static int process_renames(struct merge_options *o,
807 struct string_list *a_renames,
808 struct string_list *b_renames)
809{
810 int clean_merge = 1, i, j;
811 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
812 const struct rename *sre;
813 for (i = 0; i < a_renames->nr; i++) {
815 sre = a_renames->items[i].util;
816 string_list_insert(sre->pair->two->path, &a_by_dst)->util
817 = sre->dst_entry;
818 }
819 for (i = 0; i < b_renames->nr; i++) {
820 sre = b_renames->items[i].util;
821 string_list_insert(sre->pair->two->path, &b_by_dst)->util
822 = sre->dst_entry;
823 }
824 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
826 char *src;
827 struct string_list *renames1, *renames2Dst;
828 struct rename *ren1 = NULL, *ren2 = NULL;
829 const char *branch1, *branch2;
830 const char *ren1_src, *ren1_dst;
831 if (i >= a_renames->nr) {
833 ren2 = b_renames->items[j++].util;
834 } else if (j >= b_renames->nr) {
835 ren1 = a_renames->items[i++].util;
836 } else {
837 int compare = strcmp(a_renames->items[i].string,
838 b_renames->items[j].string);
839 if (compare <= 0)
840 ren1 = a_renames->items[i++].util;
841 if (compare >= 0)
842 ren2 = b_renames->items[j++].util;
843 }
844 /* TODO: refactor, so that 1/2 are not needed */
846 if (ren1) {
847 renames1 = a_renames;
848 renames2Dst = &b_by_dst;
849 branch1 = o->branch1;
850 branch2 = o->branch2;
851 } else {
852 struct rename *tmp;
853 renames1 = b_renames;
854 renames2Dst = &a_by_dst;
855 branch1 = o->branch2;
856 branch2 = o->branch1;
857 tmp = ren2;
858 ren2 = ren1;
859 ren1 = tmp;
860 }
861 src = ren1->pair->one->path;
862 ren1->dst_entry->processed = 1;
864 ren1->src_entry->processed = 1;
865 if (ren1->processed)
867 continue;
868 ren1->processed = 1;
869 ren1_src = ren1->pair->one->path;
871 ren1_dst = ren1->pair->two->path;
872 if (ren2) {
874 const char *ren2_src = ren2->pair->one->path;
875 const char *ren2_dst = ren2->pair->two->path;
876 /* Renamed in 1 and renamed in 2 */
877 if (strcmp(ren1_src, ren2_src) != 0)
878 die("ren1.src != ren2.src");
879 ren2->dst_entry->processed = 1;
880 ren2->processed = 1;
881 if (strcmp(ren1_dst, ren2_dst) != 0) {
882 clean_merge = 0;
883 output(o, 1, "CONFLICT (rename/rename): "
884 "Rename \"%s\"->\"%s\" in branch \"%s\" "
885 "rename \"%s\"->\"%s\" in \"%s\"%s",
886 src, ren1_dst, branch1,
887 src, ren2_dst, branch2,
888 o->call_depth ? " (left unresolved)": "");
889 if (o->call_depth) {
890 remove_file_from_cache(src);
891 update_file(o, 0, ren1->pair->one->sha1,
892 ren1->pair->one->mode, src);
893 }
894 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
895 } else {
896 struct merge_file_info mfi;
897 remove_file(o, 1, ren1_src, 1);
898 mfi = merge_file(o,
899 ren1->pair->one,
900 ren1->pair->two,
901 ren2->pair->two,
902 branch1,
903 branch2);
904 if (mfi.merge || !mfi.clean)
905 output(o, 1, "Renaming %s->%s", src, ren1_dst);
906 if (mfi.merge)
908 output(o, 2, "Auto-merging %s", ren1_dst);
909 if (!mfi.clean) {
911 output(o, 1, "CONFLICT (content): merge conflict in %s",
912 ren1_dst);
913 clean_merge = 0;
914 if (!o->call_depth)
916 update_stages(ren1_dst,
917 ren1->pair->one,
918 ren1->pair->two,
919 ren2->pair->two,
920 1 /* clear */);
921 }
922 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
923 }
924 } else {
925 /* Renamed in 1, maybe changed in 2 */
926 struct string_list_item *item;
927 /* we only use sha1 and mode of these */
928 struct diff_filespec src_other, dst_other;
929 int try_merge, stage = a_renames == renames1 ? 3: 2;
930 remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
932 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
934 src_other.mode = ren1->src_entry->stages[stage].mode;
935 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
936 dst_other.mode = ren1->dst_entry->stages[stage].mode;
937 try_merge = 0;
939 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
941 clean_merge = 0;
942 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
943 " directory %s added in %s",
944 ren1_src, ren1_dst, branch1,
945 ren1_dst, branch2);
946 conflict_rename_dir(o, ren1, branch1);
947 } else if (sha_eq(src_other.sha1, null_sha1)) {
948 clean_merge = 0;
949 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
950 "and deleted in %s",
951 ren1_src, ren1_dst, branch1,
952 branch2);
953 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
954 if (!o->call_depth)
955 update_stages(ren1_dst, NULL,
956 branch1 == o->branch1 ?
957 ren1->pair->two : NULL,
958 branch1 == o->branch1 ?
959 NULL : ren1->pair->two, 1);
960 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
961 const char *new_path;
962 clean_merge = 0;
963 try_merge = 1;
964 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
965 "%s added in %s",
966 ren1_src, ren1_dst, branch1,
967 ren1_dst, branch2);
968 if (o->call_depth) {
969 struct merge_file_info mfi;
970 struct diff_filespec one, a, b;
971 one.path = a.path = b.path =
973 (char *)ren1_dst;
974 hashcpy(one.sha1, null_sha1);
975 one.mode = 0;
976 hashcpy(a.sha1, ren1->pair->two->sha1);
977 a.mode = ren1->pair->two->mode;
978 hashcpy(b.sha1, dst_other.sha1);
979 b.mode = dst_other.mode;
980 mfi = merge_file(o, &one, &a, &b,
981 branch1,
982 branch2);
983 output(o, 1, "Adding merged %s", ren1_dst);
984 update_file(o, 0,
985 mfi.sha,
986 mfi.mode,
987 ren1_dst);
988 } else {
989 new_path = unique_path(o, ren1_dst, branch2);
990 output(o, 1, "Adding as %s instead", new_path);
991 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
992 }
993 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
994 ren2 = item->util;
995 clean_merge = 0;
996 ren2->processed = 1;
997 output(o, 1, "CONFLICT (rename/rename): "
998 "Rename %s->%s in %s. "
999 "Rename %s->%s in %s",
1000 ren1_src, ren1_dst, branch1,
1001 ren2->pair->one->path, ren2->pair->two->path, branch2);
1002 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
1003 } else
1004 try_merge = 1;
1005 if (try_merge) {
1007 struct diff_filespec *one, *a, *b;
1008 struct merge_file_info mfi;
1009 src_other.path = (char *)ren1_src;
1010 one = ren1->pair->one;
1012 if (a_renames == renames1) {
1013 a = ren1->pair->two;
1014 b = &src_other;
1015 } else {
1016 b = ren1->pair->two;
1017 a = &src_other;
1018 }
1019 mfi = merge_file(o, one, a, b,
1020 o->branch1, o->branch2);
1021 if (mfi.clean &&
1023 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1024 mfi.mode == ren1->pair->two->mode)
1025 /*
1026 * This messaged is part of
1027 * t6022 test. If you change
1028 * it update the test too.
1029 */
1030 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
1031 else {
1032 if (mfi.merge || !mfi.clean)
1033 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
1034 if (mfi.merge)
1035 output(o, 2, "Auto-merging %s", ren1_dst);
1036 if (!mfi.clean) {
1037 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
1038 ren1_dst);
1039 clean_merge = 0;
1040 if (!o->call_depth)
1042 update_stages(ren1_dst,
1043 one, a, b, 1);
1044 }
1045 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1046 }
1047 }
1048 }
1049 }
1050 string_list_clear(&a_by_dst, 0);
1051 string_list_clear(&b_by_dst, 0);
1052 return clean_merge;
1054}
1055static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1057{
1058 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1059}
1060/* Per entry merge function */
1062static int process_entry(struct merge_options *o,
1063 const char *path, struct stage_data *entry)
1064{
1065 /*
1066 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1067 print_index_entry("\tpath: ", entry);
1068 */
1069 int clean_merge = 1;
1070 unsigned o_mode = entry->stages[1].mode;
1071 unsigned a_mode = entry->stages[2].mode;
1072 unsigned b_mode = entry->stages[3].mode;
1073 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1074 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1075 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1076 if (o_sha && (!a_sha || !b_sha)) {
1078 /* Case A: Deleted in one */
1079 if ((!a_sha && !b_sha) ||
1080 (sha_eq(a_sha, o_sha) && !b_sha) ||
1081 (!a_sha && sha_eq(b_sha, o_sha))) {
1082 /* Deleted in both or deleted in one and
1083 * unchanged in the other */
1084 if (a_sha)
1085 output(o, 2, "Removing %s", path);
1086 /* do not touch working file if it did not exist */
1087 remove_file(o, 1, path, !a_sha);
1088 } else {
1089 /* Deleted in one and changed in the other */
1090 clean_merge = 0;
1091 if (!a_sha) {
1092 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1093 "and modified in %s. Version %s of %s left in tree.",
1094 path, o->branch1,
1095 o->branch2, o->branch2, path);
1096 update_file(o, 0, b_sha, b_mode, path);
1097 } else {
1098 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1099 "and modified in %s. Version %s of %s left in tree.",
1100 path, o->branch2,
1101 o->branch1, o->branch1, path);
1102 update_file(o, 0, a_sha, a_mode, path);
1103 }
1104 }
1105 } else if ((!o_sha && a_sha && !b_sha) ||
1107 (!o_sha && !a_sha && b_sha)) {
1108 /* Case B: Added in one. */
1109 const char *add_branch;
1110 const char *other_branch;
1111 unsigned mode;
1112 const unsigned char *sha;
1113 const char *conf;
1114 if (a_sha) {
1116 add_branch = o->branch1;
1117 other_branch = o->branch2;
1118 mode = a_mode;
1119 sha = a_sha;
1120 conf = "file/directory";
1121 } else {
1122 add_branch = o->branch2;
1123 other_branch = o->branch1;
1124 mode = b_mode;
1125 sha = b_sha;
1126 conf = "directory/file";
1127 }
1128 if (string_list_has_string(&o->current_directory_set, path)) {
1129 const char *new_path = unique_path(o, path, add_branch);
1130 clean_merge = 0;
1131 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1132 "Adding %s as %s",
1133 conf, path, other_branch, path, new_path);
1134 remove_file(o, 0, path, 0);
1135 update_file(o, 0, sha, mode, new_path);
1136 } else {
1137 output(o, 2, "Adding %s", path);
1138 update_file(o, 1, sha, mode, path);
1139 }
1140 } else if (a_sha && b_sha) {
1141 /* Case C: Added in both (check for same permissions) and */
1142 /* case D: Modified in both, but differently. */
1143 const char *reason = "content";
1144 struct merge_file_info mfi;
1145 struct diff_filespec one, a, b;
1146 if (!o_sha) {
1148 reason = "add/add";
1149 o_sha = (unsigned char *)null_sha1;
1150 }
1151 output(o, 2, "Auto-merging %s", path);
1152 one.path = a.path = b.path = (char *)path;
1153 hashcpy(one.sha1, o_sha);
1154 one.mode = o_mode;
1155 hashcpy(a.sha1, a_sha);
1156 a.mode = a_mode;
1157 hashcpy(b.sha1, b_sha);
1158 b.mode = b_mode;
1159 mfi = merge_file(o, &one, &a, &b,
1161 o->branch1, o->branch2);
1162 clean_merge = mfi.clean;
1164 if (!mfi.clean) {
1165 if (S_ISGITLINK(mfi.mode))
1166 reason = "submodule";
1167 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1168 reason, path);
1169 }
1170 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1171 } else if (!o_sha && !a_sha && !b_sha) {
1172 /*
1173 * this entry was deleted altogether. a_mode == 0 means
1174 * we had that path and want to actively remove it.
1175 */
1176 remove_file(o, 1, path, !a_mode);
1177 } else
1178 die("Fatal merge failure, shouldn't happen.");
1179 return clean_merge;
1181}
1182int merge_trees(struct merge_options *o,
1184 struct tree *head,
1185 struct tree *merge,
1186 struct tree *common,
1187 struct tree **result)
1188{
1189 int code, clean;
1190 if (o->subtree_merge) {
1192 merge = shift_tree_object(head, merge);
1193 common = shift_tree_object(head, common);
1194 }
1195 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1197 output(o, 0, "Already uptodate!");
1198 *result = head;
1199 return 1;
1200 }
1201 code = git_merge_trees(o->call_depth, common, head, merge);
1203 if (code != 0) {
1205 if (show(o, 4) || o->call_depth)
1206 die("merging of trees %s and %s failed",
1207 sha1_to_hex(head->object.sha1),
1208 sha1_to_hex(merge->object.sha1));
1209 else
1210 exit(128);
1211 }
1212 if (unmerged_cache()) {
1214 struct string_list *entries, *re_head, *re_merge;
1215 int i;
1216 string_list_clear(&o->current_file_set, 1);
1217 string_list_clear(&o->current_directory_set, 1);
1218 get_files_dirs(o, head);
1219 get_files_dirs(o, merge);
1220 entries = get_unmerged();
1222 re_head = get_renames(o, head, common, head, merge, entries);
1223 re_merge = get_renames(o, merge, common, head, merge, entries);
1224 clean = process_renames(o, re_head, re_merge);
1225 for (i = 0; i < entries->nr; i++) {
1226 const char *path = entries->items[i].string;
1227 struct stage_data *e = entries->items[i].util;
1228 if (!e->processed
1229 && !process_entry(o, path, e))
1230 clean = 0;
1231 }
1232 string_list_clear(re_merge, 0);
1234 string_list_clear(re_head, 0);
1235 string_list_clear(entries, 1);
1236 }
1238 else
1239 clean = 1;
1240 if (o->call_depth)
1242 *result = write_tree_from_memory(o);
1243 return clean;
1245}
1246static struct commit_list *reverse_commit_list(struct commit_list *list)
1248{
1249 struct commit_list *next = NULL, *current, *backup;
1250 for (current = list; current; current = backup) {
1251 backup = current->next;
1252 current->next = next;
1253 next = current;
1254 }
1255 return next;
1256}
1257/*
1259 * Merge the commits h1 and h2, return the resulting virtual
1260 * commit object and a flag indicating the cleanness of the merge.
1261 */
1262int merge_recursive(struct merge_options *o,
1263 struct commit *h1,
1264 struct commit *h2,
1265 struct commit_list *ca,
1266 struct commit **result)
1267{
1268 struct commit_list *iter;
1269 struct commit *merged_common_ancestors;
1270 struct tree *mrtree = mrtree;
1271 int clean;
1272 if (show(o, 4)) {
1274 output(o, 4, "Merging:");
1275 output_commit_title(o, h1);
1276 output_commit_title(o, h2);
1277 }
1278 if (!ca) {
1280 ca = get_merge_bases(h1, h2, 1);
1281 ca = reverse_commit_list(ca);
1282 }
1283 if (show(o, 5)) {
1285 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1286 for (iter = ca; iter; iter = iter->next)
1287 output_commit_title(o, iter->item);
1288 }
1289 merged_common_ancestors = pop_commit(&ca);
1291 if (merged_common_ancestors == NULL) {
1292 /* if there is no common ancestor, make an empty tree */
1293 struct tree *tree = xcalloc(1, sizeof(struct tree));
1294 tree->object.parsed = 1;
1296 tree->object.type = OBJ_TREE;
1297 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1298 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1299 }
1300 for (iter = ca; iter; iter = iter->next) {
1302 const char *saved_b1, *saved_b2;
1303 o->call_depth++;
1304 /*
1305 * When the merge fails, the result contains files
1306 * with conflict markers. The cleanness flag is
1307 * ignored, it was never actually used, as result of
1308 * merge_trees has always overwritten it: the committed
1309 * "conflicts" were already resolved.
1310 */
1311 discard_cache();
1312 saved_b1 = o->branch1;
1313 saved_b2 = o->branch2;
1314 o->branch1 = "Temporary merge branch 1";
1315 o->branch2 = "Temporary merge branch 2";
1316 merge_recursive(o, merged_common_ancestors, iter->item,
1317 NULL, &merged_common_ancestors);
1318 o->branch1 = saved_b1;
1319 o->branch2 = saved_b2;
1320 o->call_depth--;
1321 if (!merged_common_ancestors)
1323 die("merge returned no commit");
1324 }
1325 discard_cache();
1327 if (!o->call_depth)
1328 read_cache();
1329 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1331 &mrtree);
1332 if (o->call_depth) {
1334 *result = make_virtual_commit(mrtree, "merged tree");
1335 commit_list_insert(h1, &(*result)->parents);
1336 commit_list_insert(h2, &(*result)->parents->next);
1337 }
1338 flush_output(o);
1339 return clean;
1340}
1341static struct commit *get_ref(const unsigned char *sha1, const char *name)
1343{
1344 struct object *object;
1345 object = deref_tag(parse_object(sha1), name, strlen(name));
1347 if (!object)
1348 return NULL;
1349 if (object->type == OBJ_TREE)
1350 return make_virtual_commit((struct tree*)object, name);
1351 if (object->type != OBJ_COMMIT)
1352 return NULL;
1353 if (parse_commit((struct commit *)object))
1354 return NULL;
1355 return (struct commit *)object;
1356}
1357int merge_recursive_generic(struct merge_options *o,
1359 const unsigned char *head,
1360 const unsigned char *merge,
1361 int num_base_list,
1362 const unsigned char **base_list,
1363 struct commit **result)
1364{
1365 int clean, index_fd;
1366 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1367 struct commit *head_commit = get_ref(head, o->branch1);
1368 struct commit *next_commit = get_ref(merge, o->branch2);
1369 struct commit_list *ca = NULL;
1370 if (base_list) {
1372 int i;
1373 for (i = 0; i < num_base_list; ++i) {
1374 struct commit *base;
1375 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1376 return error("Could not parse object '%s'",
1377 sha1_to_hex(base_list[i]));
1378 commit_list_insert(base, &ca);
1379 }
1380 }
1381 index_fd = hold_locked_index(lock, 1);
1383 clean = merge_recursive(o, head_commit, next_commit, ca,
1384 result);
1385 if (active_cache_changed &&
1386 (write_cache(index_fd, active_cache, active_nr) ||
1387 commit_locked_index(lock)))
1388 return error("Unable to write index.");
1389 return clean ? 0 : 1;
1391}
1392static int merge_recursive_config(const char *var, const char *value, void *cb)
1394{
1395 struct merge_options *o = cb;
1396 if (!strcasecmp(var, "merge.verbosity")) {
1397 o->verbosity = git_config_int(var, value);
1398 return 0;
1399 }
1400 if (!strcasecmp(var, "diff.renamelimit")) {
1401 o->diff_rename_limit = git_config_int(var, value);
1402 return 0;
1403 }
1404 if (!strcasecmp(var, "merge.renamelimit")) {
1405 o->merge_rename_limit = git_config_int(var, value);
1406 return 0;
1407 }
1408 return git_xmerge_config(var, value, cb);
1409}
1410void init_merge_options(struct merge_options *o)
1412{
1413 memset(o, 0, sizeof(struct merge_options));
1414 o->verbosity = 2;
1415 o->buffer_output = 1;
1416 o->diff_rename_limit = -1;
1417 o->merge_rename_limit = -1;
1418 git_config(merge_recursive_config, o);
1419 if (getenv("GIT_MERGE_VERBOSITY"))
1420 o->verbosity =
1421 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1422 if (o->verbosity >= 5)
1423 o->buffer_output = 0;
1424 strbuf_init(&o->obuf, 0);
1425 memset(&o->current_file_set, 0, sizeof(struct string_list));
1426 o->current_file_set.strdup_strings = 1;
1427 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1428 o->current_directory_set.strdup_strings = 1;
1429}