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 opts.msgs = get_porcelain_error_msgs();
185 init_tree_desc_from_tree(t+0, common);
187 init_tree_desc_from_tree(t+1, head);
188 init_tree_desc_from_tree(t+2, merge);
189 rc = unpack_trees(3, t, &opts);
191 cache_tree_free(&active_cache_tree);
192 return rc;
193}
194struct tree *write_tree_from_memory(struct merge_options *o)
196{
197 struct tree *result = NULL;
198 if (unmerged_cache()) {
200 int i;
201 output(o, 0, "There are unmerged index entries:");
202 for (i = 0; i < active_nr; i++) {
203 struct cache_entry *ce = active_cache[i];
204 if (ce_stage(ce))
205 output(o, 0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
206 }
207 return NULL;
208 }
209 if (!active_cache_tree)
211 active_cache_tree = cache_tree();
212 if (!cache_tree_fully_valid(active_cache_tree) &&
214 cache_tree_update(active_cache_tree,
215 active_cache, active_nr, 0, 0) < 0)
216 die("error building trees");
217 result = lookup_tree(active_cache_tree->sha1);
219 return result;
221}
222static int save_files_dirs(const unsigned char *sha1,
224 const char *base, int baselen, const char *path,
225 unsigned int mode, int stage, void *context)
226{
227 int len = strlen(path);
228 char *newpath = xmalloc(baselen + len + 1);
229 struct merge_options *o = context;
230 memcpy(newpath, base, baselen);
232 memcpy(newpath + baselen, path, len);
233 newpath[baselen + len] = '\0';
234 if (S_ISDIR(mode))
236 string_list_insert(newpath, &o->current_directory_set);
237 else
238 string_list_insert(newpath, &o->current_file_set);
239 free(newpath);
240 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
242}
243static int get_files_dirs(struct merge_options *o, struct tree *tree)
245{
246 int n;
247 if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
248 return 0;
249 n = o->current_file_set.nr + o->current_directory_set.nr;
250 return n;
251}
252/*
254 * Returns an index_entry instance which doesn't have to correspond to
255 * a real cache entry in Git's index.
256 */
257static struct stage_data *insert_stage_data(const char *path,
258 struct tree *o, struct tree *a, struct tree *b,
259 struct string_list *entries)
260{
261 struct string_list_item *item;
262 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
263 get_tree_entry(o->object.sha1, path,
264 e->stages[1].sha, &e->stages[1].mode);
265 get_tree_entry(a->object.sha1, path,
266 e->stages[2].sha, &e->stages[2].mode);
267 get_tree_entry(b->object.sha1, path,
268 e->stages[3].sha, &e->stages[3].mode);
269 item = string_list_insert(path, entries);
270 item->util = e;
271 return e;
272}
273/*
275 * Create a dictionary mapping file names to stage_data objects. The
276 * dictionary contains one entry for every path with a non-zero stage entry.
277 */
278static struct string_list *get_unmerged(void)
279{
280 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
281 int i;
282 unmerged->strdup_strings = 1;
284 for (i = 0; i < active_nr; i++) {
286 struct string_list_item *item;
287 struct stage_data *e;
288 struct cache_entry *ce = active_cache[i];
289 if (!ce_stage(ce))
290 continue;
291 item = string_list_lookup(ce->name, unmerged);
293 if (!item) {
294 item = string_list_insert(ce->name, unmerged);
295 item->util = xcalloc(1, sizeof(struct stage_data));
296 }
297 e = item->util;
298 e->stages[ce_stage(ce)].mode = ce->ce_mode;
299 hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
300 }
301 return unmerged;
303}
304struct rename
306{
307 struct diff_filepair *pair;
308 struct stage_data *src_entry;
309 struct stage_data *dst_entry;
310 unsigned processed:1;
311};
312/*
314 * Get information of all renames which occurred between 'o_tree' and
315 * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
316 * 'b_tree') to be able to associate the correct cache entries with
317 * the rename information. 'tree' is always equal to either a_tree or b_tree.
318 */
319static struct string_list *get_renames(struct merge_options *o,
320 struct tree *tree,
321 struct tree *o_tree,
322 struct tree *a_tree,
323 struct tree *b_tree,
324 struct string_list *entries)
325{
326 int i;
327 struct string_list *renames;
328 struct diff_options opts;
329 renames = xcalloc(1, sizeof(struct string_list));
331 diff_setup(&opts);
332 DIFF_OPT_SET(&opts, RECURSIVE);
333 opts.detect_rename = DIFF_DETECT_RENAME;
334 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
335 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
336 500;
337 opts.warn_on_too_large_rename = 1;
338 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
339 if (diff_setup_done(&opts) < 0)
340 die("diff setup failed");
341 diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
342 diffcore_std(&opts);
343 for (i = 0; i < diff_queued_diff.nr; ++i) {
344 struct string_list_item *item;
345 struct rename *re;
346 struct diff_filepair *pair = diff_queued_diff.queue[i];
347 if (pair->status != 'R') {
348 diff_free_filepair(pair);
349 continue;
350 }
351 re = xmalloc(sizeof(*re));
352 re->processed = 0;
353 re->pair = pair;
354 item = string_list_lookup(re->pair->one->path, entries);
355 if (!item)
356 re->src_entry = insert_stage_data(re->pair->one->path,
357 o_tree, a_tree, b_tree, entries);
358 else
359 re->src_entry = item->util;
360 item = string_list_lookup(re->pair->two->path, entries);
362 if (!item)
363 re->dst_entry = insert_stage_data(re->pair->two->path,
364 o_tree, a_tree, b_tree, entries);
365 else
366 re->dst_entry = item->util;
367 item = string_list_insert(pair->one->path, renames);
368 item->util = re;
369 }
370 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
371 diff_queued_diff.nr = 0;
372 diff_flush(&opts);
373 return renames;
374}
375static int update_stages(const char *path, struct diff_filespec *o,
377 struct diff_filespec *a, struct diff_filespec *b,
378 int clear)
379{
380 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
381 if (clear)
382 if (remove_file_from_cache(path))
383 return -1;
384 if (o)
385 if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
386 return -1;
387 if (a)
388 if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
389 return -1;
390 if (b)
391 if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
392 return -1;
393 return 0;
394}
395static int remove_file(struct merge_options *o, int clean,
397 const char *path, int no_wd)
398{
399 int update_cache = o->call_depth || clean;
400 int update_working_directory = !o->call_depth && !no_wd;
401 if (update_cache) {
403 if (remove_file_from_cache(path))
404 return -1;
405 }
406 if (update_working_directory) {
407 if (remove_path(path) && errno != ENOENT)
408 return -1;
409 }
410 return 0;
411}
412static char *unique_path(struct merge_options *o, const char *path, const char *branch)
414{
415 char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
416 int suffix = 0;
417 struct stat st;
418 char *p = newpath + strlen(path);
419 strcpy(newpath, path);
420 *(p++) = '~';
421 strcpy(p, branch);
422 for (; *p; ++p)
423 if ('/' == *p)
424 *p = '_';
425 while (string_list_has_string(&o->current_file_set, newpath) ||
426 string_list_has_string(&o->current_directory_set, newpath) ||
427 lstat(newpath, &st) == 0)
428 sprintf(p, "_%d", suffix++);
429 string_list_insert(newpath, &o->current_file_set);
431 return newpath;
432}
433static void flush_buffer(int fd, const char *buf, unsigned long size)
435{
436 while (size > 0) {
437 long ret = write_in_full(fd, buf, size);
438 if (ret < 0) {
439 /* Ignore epipe */
440 if (errno == EPIPE)
441 break;
442 die_errno("merge-recursive");
443 } else if (!ret) {
444 die("merge-recursive: disk full?");
445 }
446 size -= ret;
447 buf += ret;
448 }
449}
450static int would_lose_untracked(const char *path)
452{
453 int pos = cache_name_pos(path, strlen(path));
454 if (pos < 0)
456 pos = -1 - pos;
457 while (pos < active_nr &&
458 !strcmp(path, active_cache[pos]->name)) {
459 /*
460 * If stage #0, it is definitely tracked.
461 * If it has stage #2 then it was tracked
462 * before this merge started. All other
463 * cases the path was not tracked.
464 */
465 switch (ce_stage(active_cache[pos])) {
466 case 0:
467 case 2:
468 return 0;
469 }
470 pos++;
471 }
472 return file_exists(path);
473}
474static int make_room_for_path(const char *path)
476{
477 int status;
478 const char *msg = "failed to create path '%s'%s";
479 status = safe_create_leading_directories_const(path);
481 if (status) {
482 if (status == -3) {
483 /* something else exists */
484 error(msg, path, ": perhaps a D/F conflict?");
485 return -1;
486 }
487 die(msg, path, "");
488 }
489 /*
491 * Do not unlink a file in the work tree if we are not
492 * tracking it.
493 */
494 if (would_lose_untracked(path))
495 return error("refusing to lose untracked file at '%s'",
496 path);
497 /* Successful unlink is good.. */
499 if (!unlink(path))
500 return 0;
501 /* .. and so is no existing file */
502 if (errno == ENOENT)
503 return 0;
504 /* .. but not some other error (who really cares what?) */
505 return error(msg, path, ": perhaps a D/F conflict?");
506}
507static void update_file_flags(struct merge_options *o,
509 const unsigned char *sha,
510 unsigned mode,
511 const char *path,
512 int update_cache,
513 int update_wd)
514{
515 if (o->call_depth)
516 update_wd = 0;
517 if (update_wd) {
519 enum object_type type;
520 void *buf;
521 unsigned long size;
522 if (S_ISGITLINK(mode))
524 /*
525 * We may later decide to recursively descend into
526 * the submodule directory and update its index
527 * and/or work tree, but we do not do that now.
528 */
529 goto update_index;
530 buf = read_sha1_file(sha, &type, &size);
532 if (!buf)
533 die("cannot read object %s '%s'", sha1_to_hex(sha), path);
534 if (type != OBJ_BLOB)
535 die("blob expected for %s '%s'", sha1_to_hex(sha), path);
536 if (S_ISREG(mode)) {
537 struct strbuf strbuf = STRBUF_INIT;
538 if (convert_to_working_tree(path, buf, size, &strbuf)) {
539 free(buf);
540 size = strbuf.len;
541 buf = strbuf_detach(&strbuf, NULL);
542 }
543 }
544 if (make_room_for_path(path) < 0) {
546 update_wd = 0;
547 free(buf);
548 goto update_index;
549 }
550 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
551 int fd;
552 if (mode & 0100)
553 mode = 0777;
554 else
555 mode = 0666;
556 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
557 if (fd < 0)
558 die_errno("failed to open '%s'", path);
559 flush_buffer(fd, buf, size);
560 close(fd);
561 } else if (S_ISLNK(mode)) {
562 char *lnk = xmemdupz(buf, size);
563 safe_create_leading_directories_const(path);
564 unlink(path);
565 if (symlink(lnk, path))
566 die_errno("failed to symlink '%s'", path);
567 free(lnk);
568 } else
569 die("do not know what to do with %06o %s '%s'",
570 mode, sha1_to_hex(sha), path);
571 free(buf);
572 }
573 update_index:
574 if (update_cache)
575 add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
576}
577static void update_file(struct merge_options *o,
579 int clean,
580 const unsigned char *sha,
581 unsigned mode,
582 const char *path)
583{
584 update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
585}
586/* Low level file merging, update and removal */
588struct merge_file_info
590{
591 unsigned char sha[20];
592 unsigned mode;
593 unsigned clean:1,
594 merge:1;
595};
596static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
598{
599 unsigned long size;
600 enum object_type type;
601 if (!hashcmp(sha1, null_sha1)) {
603 mm->ptr = xstrdup("");
604 mm->size = 0;
605 return;
606 }
607 mm->ptr = read_sha1_file(sha1, &type, &size);
609 if (!mm->ptr || type != OBJ_BLOB)
610 die("unable to read blob object %s", sha1_to_hex(sha1));
611 mm->size = size;
612}
613static int merge_3way(struct merge_options *o,
615 mmbuffer_t *result_buf,
616 struct diff_filespec *one,
617 struct diff_filespec *a,
618 struct diff_filespec *b,
619 const char *branch1,
620 const char *branch2)
621{
622 mmfile_t orig, src1, src2;
623 char *name1, *name2;
624 int merge_status;
625 if (strcmp(a->path, b->path)) {
627 name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
628 name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
629 } else {
630 name1 = xstrdup(mkpath("%s", branch1));
631 name2 = xstrdup(mkpath("%s", branch2));
632 }
633 fill_mm(one->sha1, &orig);
635 fill_mm(a->sha1, &src1);
636 fill_mm(b->sha1, &src2);
637 merge_status = ll_merge(result_buf, a->path, &orig,
639 &src1, name1, &src2, name2,
640 o->call_depth);
641 free(name1);
643 free(name2);
644 free(orig.ptr);
645 free(src1.ptr);
646 free(src2.ptr);
647 return merge_status;
648}
649static struct merge_file_info merge_file(struct merge_options *o,
651 struct diff_filespec *one,
652 struct diff_filespec *a,
653 struct diff_filespec *b,
654 const char *branch1,
655 const char *branch2)
656{
657 struct merge_file_info result;
658 result.merge = 0;
659 result.clean = 1;
660 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
662 result.clean = 0;
663 if (S_ISREG(a->mode)) {
664 result.mode = a->mode;
665 hashcpy(result.sha, a->sha1);
666 } else {
667 result.mode = b->mode;
668 hashcpy(result.sha, b->sha1);
669 }
670 } else {
671 if (!sha_eq(a->sha1, one->sha1) && !sha_eq(b->sha1, one->sha1))
672 result.merge = 1;
673 /*
675 * Merge modes
676 */
677 if (a->mode == b->mode || a->mode == one->mode)
678 result.mode = b->mode;
679 else {
680 result.mode = a->mode;
681 if (b->mode != one->mode) {
682 result.clean = 0;
683 result.merge = 1;
684 }
685 }
686 if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
688 hashcpy(result.sha, b->sha1);
689 else if (sha_eq(b->sha1, one->sha1))
690 hashcpy(result.sha, a->sha1);
691 else if (S_ISREG(a->mode)) {
692 mmbuffer_t result_buf;
693 int merge_status;
694 merge_status = merge_3way(o, &result_buf, one, a, b,
696 branch1, branch2);
697 if ((merge_status < 0) || !result_buf.ptr)
699 die("Failed to execute internal merge");
700 if (write_sha1_file(result_buf.ptr, result_buf.size,
702 blob_type, result.sha))
703 die("Unable to add %s to database",
704 a->path);
705 free(result_buf.ptr);
707 result.clean = (merge_status == 0);
708 } else if (S_ISGITLINK(a->mode)) {
709 result.clean = 0;
710 hashcpy(result.sha, a->sha1);
711 } else if (S_ISLNK(a->mode)) {
712 hashcpy(result.sha, a->sha1);
713 if (!sha_eq(a->sha1, b->sha1))
715 result.clean = 0;
716 } else {
717 die("unsupported object type in the tree");
718 }
719 }
720 return result;
722}
723static void conflict_rename_rename(struct merge_options *o,
725 struct rename *ren1,
726 const char *branch1,
727 struct rename *ren2,
728 const char *branch2)
729{
730 char *del[2];
731 int delp = 0;
732 const char *ren1_dst = ren1->pair->two->path;
733 const char *ren2_dst = ren2->pair->two->path;
734 const char *dst_name1 = ren1_dst;
735 const char *dst_name2 = ren2_dst;
736 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
737 dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
738 output(o, 1, "%s is a directory in %s adding as %s instead",
739 ren1_dst, branch2, dst_name1);
740 remove_file(o, 0, ren1_dst, 0);
741 }
742 if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
743 dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
744 output(o, 1, "%s is a directory in %s adding as %s instead",
745 ren2_dst, branch1, dst_name2);
746 remove_file(o, 0, ren2_dst, 0);
747 }
748 if (o->call_depth) {
749 remove_file_from_cache(dst_name1);
750 remove_file_from_cache(dst_name2);
751 /*
752 * Uncomment to leave the conflicting names in the resulting tree
753 *
754 * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
755 * update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
756 */
757 } else {
758 update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
759 update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
760 }
761 while (delp--)
762 free(del[delp]);
763}
764static void conflict_rename_dir(struct merge_options *o,
766 struct rename *ren1,
767 const char *branch1)
768{
769 char *new_path = unique_path(o, ren1->pair->two->path, branch1);
770 output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
771 remove_file(o, 0, ren1->pair->two->path, 0);
772 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
773 free(new_path);
774}
775static void conflict_rename_rename_2(struct merge_options *o,
777 struct rename *ren1,
778 const char *branch1,
779 struct rename *ren2,
780 const char *branch2)
781{
782 char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
783 char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
784 output(o, 1, "Renaming %s to %s and %s to %s instead",
785 ren1->pair->one->path, new_path1,
786 ren2->pair->one->path, new_path2);
787 remove_file(o, 0, ren1->pair->two->path, 0);
788 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
789 update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
790 free(new_path2);
791 free(new_path1);
792}
793static int process_renames(struct merge_options *o,
795 struct string_list *a_renames,
796 struct string_list *b_renames)
797{
798 int clean_merge = 1, i, j;
799 struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
800 const struct rename *sre;
801 for (i = 0; i < a_renames->nr; i++) {
803 sre = a_renames->items[i].util;
804 string_list_insert(sre->pair->two->path, &a_by_dst)->util
805 = sre->dst_entry;
806 }
807 for (i = 0; i < b_renames->nr; i++) {
808 sre = b_renames->items[i].util;
809 string_list_insert(sre->pair->two->path, &b_by_dst)->util
810 = sre->dst_entry;
811 }
812 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
814 char *src;
815 struct string_list *renames1, *renames2Dst;
816 struct rename *ren1 = NULL, *ren2 = NULL;
817 const char *branch1, *branch2;
818 const char *ren1_src, *ren1_dst;
819 if (i >= a_renames->nr) {
821 ren2 = b_renames->items[j++].util;
822 } else if (j >= b_renames->nr) {
823 ren1 = a_renames->items[i++].util;
824 } else {
825 int compare = strcmp(a_renames->items[i].string,
826 b_renames->items[j].string);
827 if (compare <= 0)
828 ren1 = a_renames->items[i++].util;
829 if (compare >= 0)
830 ren2 = b_renames->items[j++].util;
831 }
832 /* TODO: refactor, so that 1/2 are not needed */
834 if (ren1) {
835 renames1 = a_renames;
836 renames2Dst = &b_by_dst;
837 branch1 = o->branch1;
838 branch2 = o->branch2;
839 } else {
840 struct rename *tmp;
841 renames1 = b_renames;
842 renames2Dst = &a_by_dst;
843 branch1 = o->branch2;
844 branch2 = o->branch1;
845 tmp = ren2;
846 ren2 = ren1;
847 ren1 = tmp;
848 }
849 src = ren1->pair->one->path;
850 ren1->dst_entry->processed = 1;
852 ren1->src_entry->processed = 1;
853 if (ren1->processed)
855 continue;
856 ren1->processed = 1;
857 ren1_src = ren1->pair->one->path;
859 ren1_dst = ren1->pair->two->path;
860 if (ren2) {
862 const char *ren2_src = ren2->pair->one->path;
863 const char *ren2_dst = ren2->pair->two->path;
864 /* Renamed in 1 and renamed in 2 */
865 if (strcmp(ren1_src, ren2_src) != 0)
866 die("ren1.src != ren2.src");
867 ren2->dst_entry->processed = 1;
868 ren2->processed = 1;
869 if (strcmp(ren1_dst, ren2_dst) != 0) {
870 clean_merge = 0;
871 output(o, 1, "CONFLICT (rename/rename): "
872 "Rename \"%s\"->\"%s\" in branch \"%s\" "
873 "rename \"%s\"->\"%s\" in \"%s\"%s",
874 src, ren1_dst, branch1,
875 src, ren2_dst, branch2,
876 o->call_depth ? " (left unresolved)": "");
877 if (o->call_depth) {
878 remove_file_from_cache(src);
879 update_file(o, 0, ren1->pair->one->sha1,
880 ren1->pair->one->mode, src);
881 }
882 conflict_rename_rename(o, ren1, branch1, ren2, branch2);
883 } else {
884 struct merge_file_info mfi;
885 remove_file(o, 1, ren1_src, 1);
886 mfi = merge_file(o,
887 ren1->pair->one,
888 ren1->pair->two,
889 ren2->pair->two,
890 branch1,
891 branch2);
892 if (mfi.merge || !mfi.clean)
893 output(o, 1, "Renaming %s->%s", src, ren1_dst);
894 if (mfi.merge)
896 output(o, 2, "Auto-merging %s", ren1_dst);
897 if (!mfi.clean) {
899 output(o, 1, "CONFLICT (content): merge conflict in %s",
900 ren1_dst);
901 clean_merge = 0;
902 if (!o->call_depth)
904 update_stages(ren1_dst,
905 ren1->pair->one,
906 ren1->pair->two,
907 ren2->pair->two,
908 1 /* clear */);
909 }
910 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
911 }
912 } else {
913 /* Renamed in 1, maybe changed in 2 */
914 struct string_list_item *item;
915 /* we only use sha1 and mode of these */
916 struct diff_filespec src_other, dst_other;
917 int try_merge, stage = a_renames == renames1 ? 3: 2;
918 remove_file(o, 1, ren1_src, o->call_depth || stage == 3);
920 hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
922 src_other.mode = ren1->src_entry->stages[stage].mode;
923 hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
924 dst_other.mode = ren1->dst_entry->stages[stage].mode;
925 try_merge = 0;
927 if (string_list_has_string(&o->current_directory_set, ren1_dst)) {
929 clean_merge = 0;
930 output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
931 " directory %s added in %s",
932 ren1_src, ren1_dst, branch1,
933 ren1_dst, branch2);
934 conflict_rename_dir(o, ren1, branch1);
935 } else if (sha_eq(src_other.sha1, null_sha1)) {
936 clean_merge = 0;
937 output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
938 "and deleted in %s",
939 ren1_src, ren1_dst, branch1,
940 branch2);
941 update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
942 if (!o->call_depth)
943 update_stages(ren1_dst, NULL,
944 branch1 == o->branch1 ?
945 ren1->pair->two : NULL,
946 branch1 == o->branch1 ?
947 NULL : ren1->pair->two, 1);
948 } else if (!sha_eq(dst_other.sha1, null_sha1)) {
949 const char *new_path;
950 clean_merge = 0;
951 try_merge = 1;
952 output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
953 "%s added in %s",
954 ren1_src, ren1_dst, branch1,
955 ren1_dst, branch2);
956 if (o->call_depth) {
957 struct merge_file_info mfi;
958 struct diff_filespec one, a, b;
959 one.path = a.path = b.path =
961 (char *)ren1_dst;
962 hashcpy(one.sha1, null_sha1);
963 one.mode = 0;
964 hashcpy(a.sha1, ren1->pair->two->sha1);
965 a.mode = ren1->pair->two->mode;
966 hashcpy(b.sha1, dst_other.sha1);
967 b.mode = dst_other.mode;
968 mfi = merge_file(o, &one, &a, &b,
969 branch1,
970 branch2);
971 output(o, 1, "Adding merged %s", ren1_dst);
972 update_file(o, 0,
973 mfi.sha,
974 mfi.mode,
975 ren1_dst);
976 } else {
977 new_path = unique_path(o, ren1_dst, branch2);
978 output(o, 1, "Adding as %s instead", new_path);
979 update_file(o, 0, dst_other.sha1, dst_other.mode, new_path);
980 }
981 } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
982 ren2 = item->util;
983 clean_merge = 0;
984 ren2->processed = 1;
985 output(o, 1, "CONFLICT (rename/rename): "
986 "Rename %s->%s in %s. "
987 "Rename %s->%s in %s",
988 ren1_src, ren1_dst, branch1,
989 ren2->pair->one->path, ren2->pair->two->path, branch2);
990 conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
991 } else
992 try_merge = 1;
993 if (try_merge) {
995 struct diff_filespec *one, *a, *b;
996 struct merge_file_info mfi;
997 src_other.path = (char *)ren1_src;
998 one = ren1->pair->one;
1000 if (a_renames == renames1) {
1001 a = ren1->pair->two;
1002 b = &src_other;
1003 } else {
1004 b = ren1->pair->two;
1005 a = &src_other;
1006 }
1007 mfi = merge_file(o, one, a, b,
1008 o->branch1, o->branch2);
1009 if (mfi.clean &&
1011 sha_eq(mfi.sha, ren1->pair->two->sha1) &&
1012 mfi.mode == ren1->pair->two->mode)
1013 /*
1014 * This messaged is part of
1015 * t6022 test. If you change
1016 * it update the test too.
1017 */
1018 output(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
1019 else {
1020 if (mfi.merge || !mfi.clean)
1021 output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
1022 if (mfi.merge)
1023 output(o, 2, "Auto-merging %s", ren1_dst);
1024 if (!mfi.clean) {
1025 output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
1026 ren1_dst);
1027 clean_merge = 0;
1028 if (!o->call_depth)
1030 update_stages(ren1_dst,
1031 one, a, b, 1);
1032 }
1033 update_file(o, mfi.clean, mfi.sha, mfi.mode, ren1_dst);
1034 }
1035 }
1036 }
1037 }
1038 string_list_clear(&a_by_dst, 0);
1039 string_list_clear(&b_by_dst, 0);
1040 return clean_merge;
1042}
1043static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
1045{
1046 return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
1047}
1048/* Per entry merge function */
1050static int process_entry(struct merge_options *o,
1051 const char *path, struct stage_data *entry)
1052{
1053 /*
1054 printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
1055 print_index_entry("\tpath: ", entry);
1056 */
1057 int clean_merge = 1;
1058 unsigned o_mode = entry->stages[1].mode;
1059 unsigned a_mode = entry->stages[2].mode;
1060 unsigned b_mode = entry->stages[3].mode;
1061 unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
1062 unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
1063 unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
1064 if (o_sha && (!a_sha || !b_sha)) {
1066 /* Case A: Deleted in one */
1067 if ((!a_sha && !b_sha) ||
1068 (sha_eq(a_sha, o_sha) && !b_sha) ||
1069 (!a_sha && sha_eq(b_sha, o_sha))) {
1070 /* Deleted in both or deleted in one and
1071 * unchanged in the other */
1072 if (a_sha)
1073 output(o, 2, "Removing %s", path);
1074 /* do not touch working file if it did not exist */
1075 remove_file(o, 1, path, !a_sha);
1076 } else {
1077 /* Deleted in one and changed in the other */
1078 clean_merge = 0;
1079 if (!a_sha) {
1080 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1081 "and modified in %s. Version %s of %s left in tree.",
1082 path, o->branch1,
1083 o->branch2, o->branch2, path);
1084 update_file(o, 0, b_sha, b_mode, path);
1085 } else {
1086 output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
1087 "and modified in %s. Version %s of %s left in tree.",
1088 path, o->branch2,
1089 o->branch1, o->branch1, path);
1090 update_file(o, 0, a_sha, a_mode, path);
1091 }
1092 }
1093 } else if ((!o_sha && a_sha && !b_sha) ||
1095 (!o_sha && !a_sha && b_sha)) {
1096 /* Case B: Added in one. */
1097 const char *add_branch;
1098 const char *other_branch;
1099 unsigned mode;
1100 const unsigned char *sha;
1101 const char *conf;
1102 if (a_sha) {
1104 add_branch = o->branch1;
1105 other_branch = o->branch2;
1106 mode = a_mode;
1107 sha = a_sha;
1108 conf = "file/directory";
1109 } else {
1110 add_branch = o->branch2;
1111 other_branch = o->branch1;
1112 mode = b_mode;
1113 sha = b_sha;
1114 conf = "directory/file";
1115 }
1116 if (string_list_has_string(&o->current_directory_set, path)) {
1117 const char *new_path = unique_path(o, path, add_branch);
1118 clean_merge = 0;
1119 output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
1120 "Adding %s as %s",
1121 conf, path, other_branch, path, new_path);
1122 remove_file(o, 0, path, 0);
1123 update_file(o, 0, sha, mode, new_path);
1124 } else {
1125 output(o, 2, "Adding %s", path);
1126 update_file(o, 1, sha, mode, path);
1127 }
1128 } else if (a_sha && b_sha) {
1129 /* Case C: Added in both (check for same permissions) and */
1130 /* case D: Modified in both, but differently. */
1131 const char *reason = "content";
1132 struct merge_file_info mfi;
1133 struct diff_filespec one, a, b;
1134 if (!o_sha) {
1136 reason = "add/add";
1137 o_sha = (unsigned char *)null_sha1;
1138 }
1139 output(o, 2, "Auto-merging %s", path);
1140 one.path = a.path = b.path = (char *)path;
1141 hashcpy(one.sha1, o_sha);
1142 one.mode = o_mode;
1143 hashcpy(a.sha1, a_sha);
1144 a.mode = a_mode;
1145 hashcpy(b.sha1, b_sha);
1146 b.mode = b_mode;
1147 mfi = merge_file(o, &one, &a, &b,
1149 o->branch1, o->branch2);
1150 clean_merge = mfi.clean;
1152 if (!mfi.clean) {
1153 if (S_ISGITLINK(mfi.mode))
1154 reason = "submodule";
1155 output(o, 1, "CONFLICT (%s): Merge conflict in %s",
1156 reason, path);
1157 }
1158 update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
1159 } else if (!o_sha && !a_sha && !b_sha) {
1160 /*
1161 * this entry was deleted altogether. a_mode == 0 means
1162 * we had that path and want to actively remove it.
1163 */
1164 remove_file(o, 1, path, !a_mode);
1165 } else
1166 die("Fatal merge failure, shouldn't happen.");
1167 return clean_merge;
1169}
1170struct unpack_trees_error_msgs get_porcelain_error_msgs(void)
1172{
1173 struct unpack_trees_error_msgs msgs = {
1174 /* would_overwrite */
1175 "Your local changes to '%s' would be overwritten by merge. Aborting.",
1176 /* not_uptodate_file */
1177 "Your local changes to '%s' would be overwritten by merge. Aborting.",
1178 /* not_uptodate_dir */
1179 "Updating '%s' would lose untracked files in it. Aborting.",
1180 /* would_lose_untracked */
1181 "Untracked working tree file '%s' would be %s by merge. Aborting",
1182 /* bind_overlap -- will not happen here */
1183 NULL,
1184 };
1185 return msgs;
1186}
1187int merge_trees(struct merge_options *o,
1189 struct tree *head,
1190 struct tree *merge,
1191 struct tree *common,
1192 struct tree **result)
1193{
1194 int code, clean;
1195 if (o->subtree_merge) {
1197 merge = shift_tree_object(head, merge);
1198 common = shift_tree_object(head, common);
1199 }
1200 if (sha_eq(common->object.sha1, merge->object.sha1)) {
1202 output(o, 0, "Already uptodate!");
1203 *result = head;
1204 return 1;
1205 }
1206 code = git_merge_trees(o->call_depth, common, head, merge);
1208 if (code != 0) {
1210 if (show(o, 4) || o->call_depth)
1211 die("merging of trees %s and %s failed",
1212 sha1_to_hex(head->object.sha1),
1213 sha1_to_hex(merge->object.sha1));
1214 else
1215 exit(128);
1216 }
1217 if (unmerged_cache()) {
1219 struct string_list *entries, *re_head, *re_merge;
1220 int i;
1221 string_list_clear(&o->current_file_set, 1);
1222 string_list_clear(&o->current_directory_set, 1);
1223 get_files_dirs(o, head);
1224 get_files_dirs(o, merge);
1225 entries = get_unmerged();
1227 re_head = get_renames(o, head, common, head, merge, entries);
1228 re_merge = get_renames(o, merge, common, head, merge, entries);
1229 clean = process_renames(o, re_head, re_merge);
1230 for (i = 0; i < entries->nr; i++) {
1231 const char *path = entries->items[i].string;
1232 struct stage_data *e = entries->items[i].util;
1233 if (!e->processed
1234 && !process_entry(o, path, e))
1235 clean = 0;
1236 }
1237 string_list_clear(re_merge, 0);
1239 string_list_clear(re_head, 0);
1240 string_list_clear(entries, 1);
1241 }
1243 else
1244 clean = 1;
1245 if (o->call_depth)
1247 *result = write_tree_from_memory(o);
1248 return clean;
1250}
1251static struct commit_list *reverse_commit_list(struct commit_list *list)
1253{
1254 struct commit_list *next = NULL, *current, *backup;
1255 for (current = list; current; current = backup) {
1256 backup = current->next;
1257 current->next = next;
1258 next = current;
1259 }
1260 return next;
1261}
1262/*
1264 * Merge the commits h1 and h2, return the resulting virtual
1265 * commit object and a flag indicating the cleanness of the merge.
1266 */
1267int merge_recursive(struct merge_options *o,
1268 struct commit *h1,
1269 struct commit *h2,
1270 struct commit_list *ca,
1271 struct commit **result)
1272{
1273 struct commit_list *iter;
1274 struct commit *merged_common_ancestors;
1275 struct tree *mrtree = mrtree;
1276 int clean;
1277 if (show(o, 4)) {
1279 output(o, 4, "Merging:");
1280 output_commit_title(o, h1);
1281 output_commit_title(o, h2);
1282 }
1283 if (!ca) {
1285 ca = get_merge_bases(h1, h2, 1);
1286 ca = reverse_commit_list(ca);
1287 }
1288 if (show(o, 5)) {
1290 output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
1291 for (iter = ca; iter; iter = iter->next)
1292 output_commit_title(o, iter->item);
1293 }
1294 merged_common_ancestors = pop_commit(&ca);
1296 if (merged_common_ancestors == NULL) {
1297 /* if there is no common ancestor, make an empty tree */
1298 struct tree *tree = xcalloc(1, sizeof(struct tree));
1299 tree->object.parsed = 1;
1301 tree->object.type = OBJ_TREE;
1302 pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
1303 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
1304 }
1305 for (iter = ca; iter; iter = iter->next) {
1307 const char *saved_b1, *saved_b2;
1308 o->call_depth++;
1309 /*
1310 * When the merge fails, the result contains files
1311 * with conflict markers. The cleanness flag is
1312 * ignored, it was never actually used, as result of
1313 * merge_trees has always overwritten it: the committed
1314 * "conflicts" were already resolved.
1315 */
1316 discard_cache();
1317 saved_b1 = o->branch1;
1318 saved_b2 = o->branch2;
1319 o->branch1 = "Temporary merge branch 1";
1320 o->branch2 = "Temporary merge branch 2";
1321 merge_recursive(o, merged_common_ancestors, iter->item,
1322 NULL, &merged_common_ancestors);
1323 o->branch1 = saved_b1;
1324 o->branch2 = saved_b2;
1325 o->call_depth--;
1326 if (!merged_common_ancestors)
1328 die("merge returned no commit");
1329 }
1330 discard_cache();
1332 if (!o->call_depth)
1333 read_cache();
1334 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
1336 &mrtree);
1337 if (o->call_depth) {
1339 *result = make_virtual_commit(mrtree, "merged tree");
1340 commit_list_insert(h1, &(*result)->parents);
1341 commit_list_insert(h2, &(*result)->parents->next);
1342 }
1343 flush_output(o);
1344 return clean;
1345}
1346static struct commit *get_ref(const unsigned char *sha1, const char *name)
1348{
1349 struct object *object;
1350 object = deref_tag(parse_object(sha1), name, strlen(name));
1352 if (!object)
1353 return NULL;
1354 if (object->type == OBJ_TREE)
1355 return make_virtual_commit((struct tree*)object, name);
1356 if (object->type != OBJ_COMMIT)
1357 return NULL;
1358 if (parse_commit((struct commit *)object))
1359 return NULL;
1360 return (struct commit *)object;
1361}
1362int merge_recursive_generic(struct merge_options *o,
1364 const unsigned char *head,
1365 const unsigned char *merge,
1366 int num_base_list,
1367 const unsigned char **base_list,
1368 struct commit **result)
1369{
1370 int clean, index_fd;
1371 struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
1372 struct commit *head_commit = get_ref(head, o->branch1);
1373 struct commit *next_commit = get_ref(merge, o->branch2);
1374 struct commit_list *ca = NULL;
1375 if (base_list) {
1377 int i;
1378 for (i = 0; i < num_base_list; ++i) {
1379 struct commit *base;
1380 if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
1381 return error("Could not parse object '%s'",
1382 sha1_to_hex(base_list[i]));
1383 commit_list_insert(base, &ca);
1384 }
1385 }
1386 index_fd = hold_locked_index(lock, 1);
1388 clean = merge_recursive(o, head_commit, next_commit, ca,
1389 result);
1390 if (active_cache_changed &&
1391 (write_cache(index_fd, active_cache, active_nr) ||
1392 commit_locked_index(lock)))
1393 return error("Unable to write index.");
1394 return clean ? 0 : 1;
1396}
1397static int merge_recursive_config(const char *var, const char *value, void *cb)
1399{
1400 struct merge_options *o = cb;
1401 if (!strcasecmp(var, "merge.verbosity")) {
1402 o->verbosity = git_config_int(var, value);
1403 return 0;
1404 }
1405 if (!strcasecmp(var, "diff.renamelimit")) {
1406 o->diff_rename_limit = git_config_int(var, value);
1407 return 0;
1408 }
1409 if (!strcasecmp(var, "merge.renamelimit")) {
1410 o->merge_rename_limit = git_config_int(var, value);
1411 return 0;
1412 }
1413 return git_xmerge_config(var, value, cb);
1414}
1415void init_merge_options(struct merge_options *o)
1417{
1418 memset(o, 0, sizeof(struct merge_options));
1419 o->verbosity = 2;
1420 o->buffer_output = 1;
1421 o->diff_rename_limit = -1;
1422 o->merge_rename_limit = -1;
1423 git_config(merge_recursive_config, o);
1424 if (getenv("GIT_MERGE_VERBOSITY"))
1425 o->verbosity =
1426 strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
1427 if (o->verbosity >= 5)
1428 o->buffer_output = 0;
1429 strbuf_init(&o->obuf, 0);
1430 memset(&o->current_file_set, 0, sizeof(struct string_list));
1431 o->current_file_set.strdup_strings = 1;
1432 memset(&o->current_directory_set, 0, sizeof(struct string_list));
1433 o->current_directory_set.strdup_strings = 1;
1434}