94a9e9abaf9633906034d191a700da0c8e329e83
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 "config.h"
8#include "advice.h"
9#include "lockfile.h"
10#include "cache-tree.h"
11#include "commit.h"
12#include "blob.h"
13#include "builtin.h"
14#include "tree-walk.h"
15#include "diff.h"
16#include "diffcore.h"
17#include "tag.h"
18#include "unpack-trees.h"
19#include "string-list.h"
20#include "xdiff-interface.h"
21#include "ll-merge.h"
22#include "attr.h"
23#include "merge-recursive.h"
24#include "dir.h"
25#include "submodule.h"
26
27struct path_hashmap_entry {
28 struct hashmap_entry e;
29 char path[FLEX_ARRAY];
30};
31
32static int path_hashmap_cmp(const void *cmp_data,
33 const void *entry,
34 const void *entry_or_key,
35 const void *keydata)
36{
37 const struct path_hashmap_entry *a = entry;
38 const struct path_hashmap_entry *b = entry_or_key;
39 const char *key = keydata;
40
41 if (ignore_case)
42 return strcasecmp(a->path, key ? key : b->path);
43 else
44 return strcmp(a->path, key ? key : b->path);
45}
46
47static unsigned int path_hash(const char *path)
48{
49 return ignore_case ? strihash(path) : strhash(path);
50}
51
52static struct dir_rename_entry *dir_rename_find_entry(struct hashmap *hashmap,
53 char *dir)
54{
55 struct dir_rename_entry key;
56
57 if (dir == NULL)
58 return NULL;
59 hashmap_entry_init(&key, strhash(dir));
60 key.dir = dir;
61 return hashmap_get(hashmap, &key, NULL);
62}
63
64static int dir_rename_cmp(const void *unused_cmp_data,
65 const void *entry,
66 const void *entry_or_key,
67 const void *unused_keydata)
68{
69 const struct dir_rename_entry *e1 = entry;
70 const struct dir_rename_entry *e2 = entry_or_key;
71
72 return strcmp(e1->dir, e2->dir);
73}
74
75static void dir_rename_init(struct hashmap *map)
76{
77 hashmap_init(map, dir_rename_cmp, NULL, 0);
78}
79
80static void dir_rename_entry_init(struct dir_rename_entry *entry,
81 char *directory)
82{
83 hashmap_entry_init(entry, strhash(directory));
84 entry->dir = directory;
85 entry->non_unique_new_dir = 0;
86 strbuf_init(&entry->new_dir, 0);
87 string_list_init(&entry->possible_new_dirs, 0);
88}
89
90static struct collision_entry *collision_find_entry(struct hashmap *hashmap,
91 char *target_file)
92{
93 struct collision_entry key;
94
95 hashmap_entry_init(&key, strhash(target_file));
96 key.target_file = target_file;
97 return hashmap_get(hashmap, &key, NULL);
98}
99
100static int collision_cmp(void *unused_cmp_data,
101 const struct collision_entry *e1,
102 const struct collision_entry *e2,
103 const void *unused_keydata)
104{
105 return strcmp(e1->target_file, e2->target_file);
106}
107
108static void collision_init(struct hashmap *map)
109{
110 hashmap_init(map, (hashmap_cmp_fn) collision_cmp, NULL, 0);
111}
112
113static void flush_output(struct merge_options *o)
114{
115 if (o->buffer_output < 2 && o->obuf.len) {
116 fputs(o->obuf.buf, stdout);
117 strbuf_reset(&o->obuf);
118 }
119}
120
121static int err(struct merge_options *o, const char *err, ...)
122{
123 va_list params;
124
125 if (o->buffer_output < 2)
126 flush_output(o);
127 else {
128 strbuf_complete(&o->obuf, '\n');
129 strbuf_addstr(&o->obuf, "error: ");
130 }
131 va_start(params, err);
132 strbuf_vaddf(&o->obuf, err, params);
133 va_end(params);
134 if (o->buffer_output > 1)
135 strbuf_addch(&o->obuf, '\n');
136 else {
137 error("%s", o->obuf.buf);
138 strbuf_reset(&o->obuf);
139 }
140
141 return -1;
142}
143
144static struct tree *shift_tree_object(struct tree *one, struct tree *two,
145 const char *subtree_shift)
146{
147 struct object_id shifted;
148
149 if (!*subtree_shift) {
150 shift_tree(&one->object.oid, &two->object.oid, &shifted, 0);
151 } else {
152 shift_tree_by(&one->object.oid, &two->object.oid, &shifted,
153 subtree_shift);
154 }
155 if (!oidcmp(&two->object.oid, &shifted))
156 return two;
157 return lookup_tree(&shifted);
158}
159
160static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
161{
162 struct commit *commit = alloc_commit_node();
163
164 set_merge_remote_desc(commit, comment, (struct object *)commit);
165 commit->tree = tree;
166 commit->object.parsed = 1;
167 return commit;
168}
169
170/*
171 * Since we use get_tree_entry(), which does not put the read object into
172 * the object pool, we cannot rely on a == b.
173 */
174static int oid_eq(const struct object_id *a, const struct object_id *b)
175{
176 if (!a && !b)
177 return 2;
178 return a && b && oidcmp(a, b) == 0;
179}
180
181enum rename_type {
182 RENAME_NORMAL = 0,
183 RENAME_DELETE,
184 RENAME_ONE_FILE_TO_ONE,
185 RENAME_ONE_FILE_TO_TWO,
186 RENAME_TWO_FILES_TO_ONE
187};
188
189struct rename_conflict_info {
190 enum rename_type rename_type;
191 struct diff_filepair *pair1;
192 struct diff_filepair *pair2;
193 const char *branch1;
194 const char *branch2;
195 struct stage_data *dst_entry1;
196 struct stage_data *dst_entry2;
197 struct diff_filespec ren1_other;
198 struct diff_filespec ren2_other;
199};
200
201/*
202 * Since we want to write the index eventually, we cannot reuse the index
203 * for these (temporary) data.
204 */
205struct stage_data {
206 struct {
207 unsigned mode;
208 struct object_id oid;
209 } stages[4];
210 struct rename_conflict_info *rename_conflict_info;
211 unsigned processed:1;
212};
213
214static inline void setup_rename_conflict_info(enum rename_type rename_type,
215 struct diff_filepair *pair1,
216 struct diff_filepair *pair2,
217 const char *branch1,
218 const char *branch2,
219 struct stage_data *dst_entry1,
220 struct stage_data *dst_entry2,
221 struct merge_options *o,
222 struct stage_data *src_entry1,
223 struct stage_data *src_entry2)
224{
225 struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info));
226 ci->rename_type = rename_type;
227 ci->pair1 = pair1;
228 ci->branch1 = branch1;
229 ci->branch2 = branch2;
230
231 ci->dst_entry1 = dst_entry1;
232 dst_entry1->rename_conflict_info = ci;
233 dst_entry1->processed = 0;
234
235 assert(!pair2 == !dst_entry2);
236 if (dst_entry2) {
237 ci->dst_entry2 = dst_entry2;
238 ci->pair2 = pair2;
239 dst_entry2->rename_conflict_info = ci;
240 }
241
242 if (rename_type == RENAME_TWO_FILES_TO_ONE) {
243 /*
244 * For each rename, there could have been
245 * modifications on the side of history where that
246 * file was not renamed.
247 */
248 int ostage1 = o->branch1 == branch1 ? 3 : 2;
249 int ostage2 = ostage1 ^ 1;
250
251 ci->ren1_other.path = pair1->one->path;
252 oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid);
253 ci->ren1_other.mode = src_entry1->stages[ostage1].mode;
254
255 ci->ren2_other.path = pair2->one->path;
256 oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid);
257 ci->ren2_other.mode = src_entry2->stages[ostage2].mode;
258 }
259}
260
261static int show(struct merge_options *o, int v)
262{
263 return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
264}
265
266__attribute__((format (printf, 3, 4)))
267static void output(struct merge_options *o, int v, const char *fmt, ...)
268{
269 va_list ap;
270
271 if (!show(o, v))
272 return;
273
274 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
275
276 va_start(ap, fmt);
277 strbuf_vaddf(&o->obuf, fmt, ap);
278 va_end(ap);
279
280 strbuf_addch(&o->obuf, '\n');
281 if (!o->buffer_output)
282 flush_output(o);
283}
284
285static void output_commit_title(struct merge_options *o, struct commit *commit)
286{
287 strbuf_addchars(&o->obuf, ' ', o->call_depth * 2);
288 if (commit->util)
289 strbuf_addf(&o->obuf, "virtual %s\n",
290 merge_remote_util(commit)->name);
291 else {
292 strbuf_add_unique_abbrev(&o->obuf, commit->object.oid.hash,
293 DEFAULT_ABBREV);
294 strbuf_addch(&o->obuf, ' ');
295 if (parse_commit(commit) != 0)
296 strbuf_addstr(&o->obuf, _("(bad commit)\n"));
297 else {
298 const char *title;
299 const char *msg = get_commit_buffer(commit, NULL);
300 int len = find_commit_subject(msg, &title);
301 if (len)
302 strbuf_addf(&o->obuf, "%.*s\n", len, title);
303 unuse_commit_buffer(commit, msg);
304 }
305 }
306 flush_output(o);
307}
308
309static int add_cacheinfo(struct merge_options *o,
310 unsigned int mode, const struct object_id *oid,
311 const char *path, int stage, int refresh, int options)
312{
313 struct cache_entry *ce;
314 int ret;
315
316 ce = make_cache_entry(mode, oid ? oid->hash : null_sha1, path, stage, 0);
317 if (!ce)
318 return err(o, _("addinfo_cache failed for path '%s'"), path);
319
320 ret = add_cache_entry(ce, options);
321 if (refresh) {
322 struct cache_entry *nce;
323
324 nce = refresh_cache_entry(ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
325 if (!nce)
326 return err(o, _("addinfo_cache failed for path '%s'"), path);
327 if (nce != ce)
328 ret = add_cache_entry(nce, options);
329 }
330 return ret;
331}
332
333static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
334{
335 parse_tree(tree);
336 init_tree_desc(desc, tree->buffer, tree->size);
337}
338
339static int git_merge_trees(int index_only,
340 struct tree *common,
341 struct tree *head,
342 struct tree *merge)
343{
344 int rc;
345 struct tree_desc t[3];
346 struct unpack_trees_options opts;
347
348 memset(&opts, 0, sizeof(opts));
349 if (index_only)
350 opts.index_only = 1;
351 else
352 opts.update = 1;
353 opts.merge = 1;
354 opts.head_idx = 2;
355 opts.fn = threeway_merge;
356 opts.src_index = &the_index;
357 opts.dst_index = &the_index;
358 setup_unpack_trees_porcelain(&opts, "merge");
359
360 init_tree_desc_from_tree(t+0, common);
361 init_tree_desc_from_tree(t+1, head);
362 init_tree_desc_from_tree(t+2, merge);
363
364 rc = unpack_trees(3, t, &opts);
365 cache_tree_free(&active_cache_tree);
366 return rc;
367}
368
369struct tree *write_tree_from_memory(struct merge_options *o)
370{
371 struct tree *result = NULL;
372
373 if (unmerged_cache()) {
374 int i;
375 fprintf(stderr, "BUG: There are unmerged index entries:\n");
376 for (i = 0; i < active_nr; i++) {
377 const struct cache_entry *ce = active_cache[i];
378 if (ce_stage(ce))
379 fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce),
380 (int)ce_namelen(ce), ce->name);
381 }
382 die("BUG: unmerged index entries in merge-recursive.c");
383 }
384
385 if (!active_cache_tree)
386 active_cache_tree = cache_tree();
387
388 if (!cache_tree_fully_valid(active_cache_tree) &&
389 cache_tree_update(&the_index, 0) < 0) {
390 err(o, _("error building trees"));
391 return NULL;
392 }
393
394 result = lookup_tree(&active_cache_tree->oid);
395
396 return result;
397}
398
399static int save_files_dirs(const unsigned char *sha1,
400 struct strbuf *base, const char *path,
401 unsigned int mode, int stage, void *context)
402{
403 struct path_hashmap_entry *entry;
404 int baselen = base->len;
405 struct merge_options *o = context;
406
407 strbuf_addstr(base, path);
408
409 FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
410 hashmap_entry_init(entry, path_hash(entry->path));
411 hashmap_add(&o->current_file_dir_set, entry);
412
413 strbuf_setlen(base, baselen);
414 return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
415}
416
417static void get_files_dirs(struct merge_options *o, struct tree *tree)
418{
419 struct pathspec match_all;
420 memset(&match_all, 0, sizeof(match_all));
421 read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
422}
423
424static int get_tree_entry_if_blob(const unsigned char *tree,
425 const char *path,
426 unsigned char *hashy,
427 unsigned int *mode_o)
428{
429 int ret;
430
431 ret = get_tree_entry(tree, path, hashy, mode_o);
432 if (S_ISDIR(*mode_o)) {
433 hashcpy(hashy, null_sha1);
434 *mode_o = 0;
435 }
436 return ret;
437}
438
439/*
440 * Returns an index_entry instance which doesn't have to correspond to
441 * a real cache entry in Git's index.
442 */
443static struct stage_data *insert_stage_data(const char *path,
444 struct tree *o, struct tree *a, struct tree *b,
445 struct string_list *entries)
446{
447 struct string_list_item *item;
448 struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
449 get_tree_entry_if_blob(o->object.oid.hash, path,
450 e->stages[1].oid.hash, &e->stages[1].mode);
451 get_tree_entry_if_blob(a->object.oid.hash, path,
452 e->stages[2].oid.hash, &e->stages[2].mode);
453 get_tree_entry_if_blob(b->object.oid.hash, path,
454 e->stages[3].oid.hash, &e->stages[3].mode);
455 item = string_list_insert(entries, path);
456 item->util = e;
457 return e;
458}
459
460/*
461 * Create a dictionary mapping file names to stage_data objects. The
462 * dictionary contains one entry for every path with a non-zero stage entry.
463 */
464static struct string_list *get_unmerged(void)
465{
466 struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
467 int i;
468
469 unmerged->strdup_strings = 1;
470
471 for (i = 0; i < active_nr; i++) {
472 struct string_list_item *item;
473 struct stage_data *e;
474 const struct cache_entry *ce = active_cache[i];
475 if (!ce_stage(ce))
476 continue;
477
478 item = string_list_lookup(unmerged, ce->name);
479 if (!item) {
480 item = string_list_insert(unmerged, ce->name);
481 item->util = xcalloc(1, sizeof(struct stage_data));
482 }
483 e = item->util;
484 e->stages[ce_stage(ce)].mode = ce->ce_mode;
485 oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
486 }
487
488 return unmerged;
489}
490
491static int string_list_df_name_compare(const char *one, const char *two)
492{
493 int onelen = strlen(one);
494 int twolen = strlen(two);
495 /*
496 * Here we only care that entries for D/F conflicts are
497 * adjacent, in particular with the file of the D/F conflict
498 * appearing before files below the corresponding directory.
499 * The order of the rest of the list is irrelevant for us.
500 *
501 * To achieve this, we sort with df_name_compare and provide
502 * the mode S_IFDIR so that D/F conflicts will sort correctly.
503 * We use the mode S_IFDIR for everything else for simplicity,
504 * since in other cases any changes in their order due to
505 * sorting cause no problems for us.
506 */
507 int cmp = df_name_compare(one, onelen, S_IFDIR,
508 two, twolen, S_IFDIR);
509 /*
510 * Now that 'foo' and 'foo/bar' compare equal, we have to make sure
511 * that 'foo' comes before 'foo/bar'.
512 */
513 if (cmp)
514 return cmp;
515 return onelen - twolen;
516}
517
518static void record_df_conflict_files(struct merge_options *o,
519 struct string_list *entries)
520{
521 /* If there is a D/F conflict and the file for such a conflict
522 * currently exist in the working tree, we want to allow it to be
523 * removed to make room for the corresponding directory if needed.
524 * The files underneath the directories of such D/F conflicts will
525 * be processed before the corresponding file involved in the D/F
526 * conflict. If the D/F directory ends up being removed by the
527 * merge, then we won't have to touch the D/F file. If the D/F
528 * directory needs to be written to the working copy, then the D/F
529 * file will simply be removed (in make_room_for_path()) to make
530 * room for the necessary paths. Note that if both the directory
531 * and the file need to be present, then the D/F file will be
532 * reinstated with a new unique name at the time it is processed.
533 */
534 struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
535 const char *last_file = NULL;
536 int last_len = 0;
537 int i;
538
539 /*
540 * If we're merging merge-bases, we don't want to bother with
541 * any working directory changes.
542 */
543 if (o->call_depth)
544 return;
545
546 /* Ensure D/F conflicts are adjacent in the entries list. */
547 for (i = 0; i < entries->nr; i++) {
548 struct string_list_item *next = &entries->items[i];
549 string_list_append(&df_sorted_entries, next->string)->util =
550 next->util;
551 }
552 df_sorted_entries.cmp = string_list_df_name_compare;
553 string_list_sort(&df_sorted_entries);
554
555 string_list_clear(&o->df_conflict_file_set, 1);
556 for (i = 0; i < df_sorted_entries.nr; i++) {
557 const char *path = df_sorted_entries.items[i].string;
558 int len = strlen(path);
559 struct stage_data *e = df_sorted_entries.items[i].util;
560
561 /*
562 * Check if last_file & path correspond to a D/F conflict;
563 * i.e. whether path is last_file+'/'+<something>.
564 * If so, record that it's okay to remove last_file to make
565 * room for path and friends if needed.
566 */
567 if (last_file &&
568 len > last_len &&
569 memcmp(path, last_file, last_len) == 0 &&
570 path[last_len] == '/') {
571 string_list_insert(&o->df_conflict_file_set, last_file);
572 }
573
574 /*
575 * Determine whether path could exist as a file in the
576 * working directory as a possible D/F conflict. This
577 * will only occur when it exists in stage 2 as a
578 * file.
579 */
580 if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
581 last_file = path;
582 last_len = len;
583 } else {
584 last_file = NULL;
585 }
586 }
587 string_list_clear(&df_sorted_entries, 0);
588}
589
590struct rename {
591 struct diff_filepair *pair;
592 /*
593 * Purpose of src_entry and dst_entry:
594 *
595 * If 'before' is renamed to 'after' then src_entry will contain
596 * the versions of 'before' from the merge_base, HEAD, and MERGE in
597 * stages 1, 2, and 3; dst_entry will contain the respective
598 * versions of 'after' in corresponding locations. Thus, we have a
599 * total of six modes and oids, though some will be null. (Stage 0
600 * is ignored; we're interested in handling conflicts.)
601 *
602 * Since we don't turn on break-rewrites by default, neither
603 * src_entry nor dst_entry can have all three of their stages have
604 * non-null oids, meaning at most four of the six will be non-null.
605 * Also, since this is a rename, both src_entry and dst_entry will
606 * have at least one non-null oid, meaning at least two will be
607 * non-null. Of the six oids, a typical rename will have three be
608 * non-null. Only two implies a rename/delete, and four implies a
609 * rename/add.
610 */
611 struct stage_data *src_entry;
612 struct stage_data *dst_entry;
613 unsigned processed:1;
614};
615
616static int update_stages(struct merge_options *opt, const char *path,
617 const struct diff_filespec *o,
618 const struct diff_filespec *a,
619 const struct diff_filespec *b)
620{
621
622 /*
623 * NOTE: It is usually a bad idea to call update_stages on a path
624 * before calling update_file on that same path, since it can
625 * sometimes lead to spurious "refusing to lose untracked file..."
626 * messages from update_file (via make_room_for path via
627 * would_lose_untracked). Instead, reverse the order of the calls
628 * (executing update_file first and then update_stages).
629 */
630 int clear = 1;
631 int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
632 if (clear)
633 if (remove_file_from_cache(path))
634 return -1;
635 if (o)
636 if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options))
637 return -1;
638 if (a)
639 if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options))
640 return -1;
641 if (b)
642 if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options))
643 return -1;
644 return 0;
645}
646
647static void update_entry(struct stage_data *entry,
648 struct diff_filespec *o,
649 struct diff_filespec *a,
650 struct diff_filespec *b)
651{
652 entry->processed = 0;
653 entry->stages[1].mode = o->mode;
654 entry->stages[2].mode = a->mode;
655 entry->stages[3].mode = b->mode;
656 oidcpy(&entry->stages[1].oid, &o->oid);
657 oidcpy(&entry->stages[2].oid, &a->oid);
658 oidcpy(&entry->stages[3].oid, &b->oid);
659}
660
661static int remove_file(struct merge_options *o, int clean,
662 const char *path, int no_wd)
663{
664 int update_cache = o->call_depth || clean;
665 int update_working_directory = !o->call_depth && !no_wd;
666
667 if (update_cache) {
668 if (remove_file_from_cache(path))
669 return -1;
670 }
671 if (update_working_directory) {
672 if (ignore_case) {
673 struct cache_entry *ce;
674 ce = cache_file_exists(path, strlen(path), ignore_case);
675 if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
676 return 0;
677 }
678 if (remove_path(path))
679 return -1;
680 }
681 return 0;
682}
683
684/* add a string to a strbuf, but converting "/" to "_" */
685static void add_flattened_path(struct strbuf *out, const char *s)
686{
687 size_t i = out->len;
688 strbuf_addstr(out, s);
689 for (; i < out->len; i++)
690 if (out->buf[i] == '/')
691 out->buf[i] = '_';
692}
693
694static char *unique_path(struct merge_options *o, const char *path, const char *branch)
695{
696 struct path_hashmap_entry *entry;
697 struct strbuf newpath = STRBUF_INIT;
698 int suffix = 0;
699 size_t base_len;
700
701 strbuf_addf(&newpath, "%s~", path);
702 add_flattened_path(&newpath, branch);
703
704 base_len = newpath.len;
705 while (hashmap_get_from_hash(&o->current_file_dir_set,
706 path_hash(newpath.buf), newpath.buf) ||
707 (!o->call_depth && file_exists(newpath.buf))) {
708 strbuf_setlen(&newpath, base_len);
709 strbuf_addf(&newpath, "_%d", suffix++);
710 }
711
712 FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
713 hashmap_entry_init(entry, path_hash(entry->path));
714 hashmap_add(&o->current_file_dir_set, entry);
715 return strbuf_detach(&newpath, NULL);
716}
717
718/**
719 * Check whether a directory in the index is in the way of an incoming
720 * file. Return 1 if so. If check_working_copy is non-zero, also
721 * check the working directory. If empty_ok is non-zero, also return
722 * 0 in the case where the working-tree dir exists but is empty.
723 */
724static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
725{
726 int pos;
727 struct strbuf dirpath = STRBUF_INIT;
728 struct stat st;
729
730 strbuf_addstr(&dirpath, path);
731 strbuf_addch(&dirpath, '/');
732
733 pos = cache_name_pos(dirpath.buf, dirpath.len);
734
735 if (pos < 0)
736 pos = -1 - pos;
737 if (pos < active_nr &&
738 !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) {
739 strbuf_release(&dirpath);
740 return 1;
741 }
742
743 strbuf_release(&dirpath);
744 return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
745 !(empty_ok && is_empty_dir(path));
746}
747
748static int was_tracked(const char *path)
749{
750 int pos = cache_name_pos(path, strlen(path));
751
752 if (0 <= pos)
753 /* we have been tracking this path */
754 return 1;
755
756 /*
757 * Look for an unmerged entry for the path,
758 * specifically stage #2, which would indicate
759 * that "our" side before the merge started
760 * had the path tracked (and resulted in a conflict).
761 */
762 for (pos = -1 - pos;
763 pos < active_nr && !strcmp(path, active_cache[pos]->name);
764 pos++)
765 if (ce_stage(active_cache[pos]) == 2)
766 return 1;
767 return 0;
768}
769
770static int would_lose_untracked(const char *path)
771{
772 return !was_tracked(path) && file_exists(path);
773}
774
775static int make_room_for_path(struct merge_options *o, const char *path)
776{
777 int status, i;
778 const char *msg = _("failed to create path '%s'%s");
779
780 /* Unlink any D/F conflict files that are in the way */
781 for (i = 0; i < o->df_conflict_file_set.nr; i++) {
782 const char *df_path = o->df_conflict_file_set.items[i].string;
783 size_t pathlen = strlen(path);
784 size_t df_pathlen = strlen(df_path);
785 if (df_pathlen < pathlen &&
786 path[df_pathlen] == '/' &&
787 strncmp(path, df_path, df_pathlen) == 0) {
788 output(o, 3,
789 _("Removing %s to make room for subdirectory\n"),
790 df_path);
791 unlink(df_path);
792 unsorted_string_list_delete_item(&o->df_conflict_file_set,
793 i, 0);
794 break;
795 }
796 }
797
798 /* Make sure leading directories are created */
799 status = safe_create_leading_directories_const(path);
800 if (status) {
801 if (status == SCLD_EXISTS)
802 /* something else exists */
803 return err(o, msg, path, _(": perhaps a D/F conflict?"));
804 return err(o, msg, path, "");
805 }
806
807 /*
808 * Do not unlink a file in the work tree if we are not
809 * tracking it.
810 */
811 if (would_lose_untracked(path))
812 return err(o, _("refusing to lose untracked file at '%s'"),
813 path);
814
815 /* Successful unlink is good.. */
816 if (!unlink(path))
817 return 0;
818 /* .. and so is no existing file */
819 if (errno == ENOENT)
820 return 0;
821 /* .. but not some other error (who really cares what?) */
822 return err(o, msg, path, _(": perhaps a D/F conflict?"));
823}
824
825static int update_file_flags(struct merge_options *o,
826 const struct object_id *oid,
827 unsigned mode,
828 const char *path,
829 int update_cache,
830 int update_wd)
831{
832 int ret = 0;
833
834 if (o->call_depth)
835 update_wd = 0;
836
837 if (update_wd) {
838 enum object_type type;
839 void *buf;
840 unsigned long size;
841
842 if (S_ISGITLINK(mode)) {
843 /*
844 * We may later decide to recursively descend into
845 * the submodule directory and update its index
846 * and/or work tree, but we do not do that now.
847 */
848 update_wd = 0;
849 goto update_index;
850 }
851
852 buf = read_sha1_file(oid->hash, &type, &size);
853 if (!buf)
854 return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path);
855 if (type != OBJ_BLOB) {
856 ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path);
857 goto free_buf;
858 }
859 if (S_ISREG(mode)) {
860 struct strbuf strbuf = STRBUF_INIT;
861 if (convert_to_working_tree(path, buf, size, &strbuf)) {
862 free(buf);
863 size = strbuf.len;
864 buf = strbuf_detach(&strbuf, NULL);
865 }
866 }
867
868 if (make_room_for_path(o, path) < 0) {
869 update_wd = 0;
870 goto free_buf;
871 }
872 if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
873 int fd;
874 if (mode & 0100)
875 mode = 0777;
876 else
877 mode = 0666;
878 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
879 if (fd < 0) {
880 ret = err(o, _("failed to open '%s': %s"),
881 path, strerror(errno));
882 goto free_buf;
883 }
884 write_in_full(fd, buf, size);
885 close(fd);
886 } else if (S_ISLNK(mode)) {
887 char *lnk = xmemdupz(buf, size);
888 safe_create_leading_directories_const(path);
889 unlink(path);
890 if (symlink(lnk, path))
891 ret = err(o, _("failed to symlink '%s': %s"),
892 path, strerror(errno));
893 free(lnk);
894 } else
895 ret = err(o,
896 _("do not know what to do with %06o %s '%s'"),
897 mode, oid_to_hex(oid), path);
898 free_buf:
899 free(buf);
900 }
901 update_index:
902 if (!ret && update_cache)
903 add_cacheinfo(o, mode, oid, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
904 return ret;
905}
906
907static int update_file(struct merge_options *o,
908 int clean,
909 const struct object_id *oid,
910 unsigned mode,
911 const char *path)
912{
913 return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth);
914}
915
916/* Low level file merging, update and removal */
917
918struct merge_file_info {
919 struct object_id oid;
920 unsigned mode;
921 unsigned clean:1,
922 merge:1;
923};
924
925static int merge_3way(struct merge_options *o,
926 mmbuffer_t *result_buf,
927 const struct diff_filespec *one,
928 const struct diff_filespec *a,
929 const struct diff_filespec *b,
930 const char *branch1,
931 const char *branch2)
932{
933 mmfile_t orig, src1, src2;
934 struct ll_merge_options ll_opts = {0};
935 char *base_name, *name1, *name2;
936 int merge_status;
937
938 ll_opts.renormalize = o->renormalize;
939 ll_opts.xdl_opts = o->xdl_opts;
940
941 if (o->call_depth) {
942 ll_opts.virtual_ancestor = 1;
943 ll_opts.variant = 0;
944 } else {
945 switch (o->recursive_variant) {
946 case MERGE_RECURSIVE_OURS:
947 ll_opts.variant = XDL_MERGE_FAVOR_OURS;
948 break;
949 case MERGE_RECURSIVE_THEIRS:
950 ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
951 break;
952 default:
953 ll_opts.variant = 0;
954 break;
955 }
956 }
957
958 if (strcmp(a->path, b->path) ||
959 (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
960 base_name = o->ancestor == NULL ? NULL :
961 mkpathdup("%s:%s", o->ancestor, one->path);
962 name1 = mkpathdup("%s:%s", branch1, a->path);
963 name2 = mkpathdup("%s:%s", branch2, b->path);
964 } else {
965 base_name = o->ancestor == NULL ? NULL :
966 mkpathdup("%s", o->ancestor);
967 name1 = mkpathdup("%s", branch1);
968 name2 = mkpathdup("%s", branch2);
969 }
970
971 read_mmblob(&orig, &one->oid);
972 read_mmblob(&src1, &a->oid);
973 read_mmblob(&src2, &b->oid);
974
975 merge_status = ll_merge(result_buf, a->path, &orig, base_name,
976 &src1, name1, &src2, name2, &ll_opts);
977
978 free(base_name);
979 free(name1);
980 free(name2);
981 free(orig.ptr);
982 free(src1.ptr);
983 free(src2.ptr);
984 return merge_status;
985}
986
987static int merge_file_1(struct merge_options *o,
988 const struct diff_filespec *one,
989 const struct diff_filespec *a,
990 const struct diff_filespec *b,
991 const char *branch1,
992 const char *branch2,
993 struct merge_file_info *result)
994{
995 result->merge = 0;
996 result->clean = 1;
997
998 if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
999 result->clean = 0;
1000 if (S_ISREG(a->mode)) {
1001 result->mode = a->mode;
1002 oidcpy(&result->oid, &a->oid);
1003 } else {
1004 result->mode = b->mode;
1005 oidcpy(&result->oid, &b->oid);
1006 }
1007 } else {
1008 if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid))
1009 result->merge = 1;
1010
1011 /*
1012 * Merge modes
1013 */
1014 if (a->mode == b->mode || a->mode == one->mode)
1015 result->mode = b->mode;
1016 else {
1017 result->mode = a->mode;
1018 if (b->mode != one->mode) {
1019 result->clean = 0;
1020 result->merge = 1;
1021 }
1022 }
1023
1024 if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid))
1025 oidcpy(&result->oid, &b->oid);
1026 else if (oid_eq(&b->oid, &one->oid))
1027 oidcpy(&result->oid, &a->oid);
1028 else if (S_ISREG(a->mode)) {
1029 mmbuffer_t result_buf;
1030 int ret = 0, merge_status;
1031
1032 merge_status = merge_3way(o, &result_buf, one, a, b,
1033 branch1, branch2);
1034
1035 if ((merge_status < 0) || !result_buf.ptr)
1036 ret = err(o, _("Failed to execute internal merge"));
1037
1038 if (!ret && write_sha1_file(result_buf.ptr, result_buf.size,
1039 blob_type, result->oid.hash))
1040 ret = err(o, _("Unable to add %s to database"),
1041 a->path);
1042
1043 free(result_buf.ptr);
1044 if (ret)
1045 return ret;
1046 result->clean = (merge_status == 0);
1047 } else if (S_ISGITLINK(a->mode)) {
1048 result->clean = merge_submodule(&result->oid,
1049 one->path,
1050 &one->oid,
1051 &a->oid,
1052 &b->oid,
1053 !o->call_depth);
1054 } else if (S_ISLNK(a->mode)) {
1055 oidcpy(&result->oid, &a->oid);
1056
1057 if (!oid_eq(&a->oid, &b->oid))
1058 result->clean = 0;
1059 } else
1060 die("BUG: unsupported object type in the tree");
1061 }
1062
1063 return 0;
1064}
1065
1066static int merge_file_special_markers(struct merge_options *o,
1067 const struct diff_filespec *one,
1068 const struct diff_filespec *a,
1069 const struct diff_filespec *b,
1070 const char *branch1,
1071 const char *filename1,
1072 const char *branch2,
1073 const char *filename2,
1074 struct merge_file_info *mfi)
1075{
1076 char *side1 = NULL;
1077 char *side2 = NULL;
1078 int ret;
1079
1080 if (filename1)
1081 side1 = xstrfmt("%s:%s", branch1, filename1);
1082 if (filename2)
1083 side2 = xstrfmt("%s:%s", branch2, filename2);
1084
1085 ret = merge_file_1(o, one, a, b,
1086 side1 ? side1 : branch1,
1087 side2 ? side2 : branch2, mfi);
1088 free(side1);
1089 free(side2);
1090 return ret;
1091}
1092
1093static int merge_file_one(struct merge_options *o,
1094 const char *path,
1095 const struct object_id *o_oid, int o_mode,
1096 const struct object_id *a_oid, int a_mode,
1097 const struct object_id *b_oid, int b_mode,
1098 const char *branch1,
1099 const char *branch2,
1100 struct merge_file_info *mfi)
1101{
1102 struct diff_filespec one, a, b;
1103
1104 one.path = a.path = b.path = (char *)path;
1105 oidcpy(&one.oid, o_oid);
1106 one.mode = o_mode;
1107 oidcpy(&a.oid, a_oid);
1108 a.mode = a_mode;
1109 oidcpy(&b.oid, b_oid);
1110 b.mode = b_mode;
1111 return merge_file_1(o, &one, &a, &b, branch1, branch2, mfi);
1112}
1113
1114static int handle_change_delete(struct merge_options *o,
1115 const char *path, const char *old_path,
1116 const struct object_id *o_oid, int o_mode,
1117 const struct object_id *changed_oid,
1118 int changed_mode,
1119 const char *change_branch,
1120 const char *delete_branch,
1121 const char *change, const char *change_past)
1122{
1123 char *alt_path = NULL;
1124 const char *update_path = path;
1125 int ret = 0;
1126
1127 if (dir_in_way(path, !o->call_depth, 0)) {
1128 update_path = alt_path = unique_path(o, path, change_branch);
1129 }
1130
1131 if (o->call_depth) {
1132 /*
1133 * We cannot arbitrarily accept either a_sha or b_sha as
1134 * correct; since there is no true "middle point" between
1135 * them, simply reuse the base version for virtual merge base.
1136 */
1137 ret = remove_file_from_cache(path);
1138 if (!ret)
1139 ret = update_file(o, 0, o_oid, o_mode, update_path);
1140 } else {
1141 if (!alt_path) {
1142 if (!old_path) {
1143 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1144 "and %s in %s. Version %s of %s left in tree."),
1145 change, path, delete_branch, change_past,
1146 change_branch, change_branch, path);
1147 } else {
1148 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1149 "and %s to %s in %s. Version %s of %s left in tree."),
1150 change, old_path, delete_branch, change_past, path,
1151 change_branch, change_branch, path);
1152 }
1153 } else {
1154 if (!old_path) {
1155 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1156 "and %s in %s. Version %s of %s left in tree at %s."),
1157 change, path, delete_branch, change_past,
1158 change_branch, change_branch, path, alt_path);
1159 } else {
1160 output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s "
1161 "and %s to %s in %s. Version %s of %s left in tree at %s."),
1162 change, old_path, delete_branch, change_past, path,
1163 change_branch, change_branch, path, alt_path);
1164 }
1165 }
1166 /*
1167 * No need to call update_file() on path when change_branch ==
1168 * o->branch1 && !alt_path, since that would needlessly touch
1169 * path. We could call update_file_flags() with update_cache=0
1170 * and update_wd=0, but that's a no-op.
1171 */
1172 if (change_branch != o->branch1 || alt_path)
1173 ret = update_file(o, 0, changed_oid, changed_mode, update_path);
1174 }
1175 free(alt_path);
1176
1177 return ret;
1178}
1179
1180static int conflict_rename_delete(struct merge_options *o,
1181 struct diff_filepair *pair,
1182 const char *rename_branch,
1183 const char *delete_branch)
1184{
1185 const struct diff_filespec *orig = pair->one;
1186 const struct diff_filespec *dest = pair->two;
1187
1188 if (handle_change_delete(o,
1189 o->call_depth ? orig->path : dest->path,
1190 o->call_depth ? NULL : orig->path,
1191 &orig->oid, orig->mode,
1192 &dest->oid, dest->mode,
1193 rename_branch, delete_branch,
1194 _("rename"), _("renamed")))
1195 return -1;
1196
1197 if (o->call_depth)
1198 return remove_file_from_cache(dest->path);
1199 else
1200 return update_stages(o, dest->path, NULL,
1201 rename_branch == o->branch1 ? dest : NULL,
1202 rename_branch == o->branch1 ? NULL : dest);
1203}
1204
1205static struct diff_filespec *filespec_from_entry(struct diff_filespec *target,
1206 struct stage_data *entry,
1207 int stage)
1208{
1209 struct object_id *oid = &entry->stages[stage].oid;
1210 unsigned mode = entry->stages[stage].mode;
1211 if (mode == 0 || is_null_oid(oid))
1212 return NULL;
1213 oidcpy(&target->oid, oid);
1214 target->mode = mode;
1215 return target;
1216}
1217
1218static int handle_file(struct merge_options *o,
1219 struct diff_filespec *rename,
1220 int stage,
1221 struct rename_conflict_info *ci)
1222{
1223 char *dst_name = rename->path;
1224 struct stage_data *dst_entry;
1225 const char *cur_branch, *other_branch;
1226 struct diff_filespec other;
1227 struct diff_filespec *add;
1228 int ret;
1229
1230 if (stage == 2) {
1231 dst_entry = ci->dst_entry1;
1232 cur_branch = ci->branch1;
1233 other_branch = ci->branch2;
1234 } else {
1235 dst_entry = ci->dst_entry2;
1236 cur_branch = ci->branch2;
1237 other_branch = ci->branch1;
1238 }
1239
1240 add = filespec_from_entry(&other, dst_entry, stage ^ 1);
1241 if (add) {
1242 char *add_name = unique_path(o, rename->path, other_branch);
1243 if (update_file(o, 0, &add->oid, add->mode, add_name))
1244 return -1;
1245
1246 remove_file(o, 0, rename->path, 0);
1247 dst_name = unique_path(o, rename->path, cur_branch);
1248 } else {
1249 if (dir_in_way(rename->path, !o->call_depth, 0)) {
1250 dst_name = unique_path(o, rename->path, cur_branch);
1251 output(o, 1, _("%s is a directory in %s adding as %s instead"),
1252 rename->path, other_branch, dst_name);
1253 }
1254 }
1255 if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name)))
1256 ; /* fall through, do allow dst_name to be released */
1257 else if (stage == 2)
1258 ret = update_stages(o, rename->path, NULL, rename, add);
1259 else
1260 ret = update_stages(o, rename->path, NULL, add, rename);
1261
1262 if (dst_name != rename->path)
1263 free(dst_name);
1264
1265 return ret;
1266}
1267
1268static int conflict_rename_rename_1to2(struct merge_options *o,
1269 struct rename_conflict_info *ci)
1270{
1271 /* One file was renamed in both branches, but to different names. */
1272 struct diff_filespec *one = ci->pair1->one;
1273 struct diff_filespec *a = ci->pair1->two;
1274 struct diff_filespec *b = ci->pair2->two;
1275
1276 output(o, 1, _("CONFLICT (rename/rename): "
1277 "Rename \"%s\"->\"%s\" in branch \"%s\" "
1278 "rename \"%s\"->\"%s\" in \"%s\"%s"),
1279 one->path, a->path, ci->branch1,
1280 one->path, b->path, ci->branch2,
1281 o->call_depth ? _(" (left unresolved)") : "");
1282 if (o->call_depth) {
1283 struct merge_file_info mfi;
1284 struct diff_filespec other;
1285 struct diff_filespec *add;
1286 if (merge_file_one(o, one->path,
1287 &one->oid, one->mode,
1288 &a->oid, a->mode,
1289 &b->oid, b->mode,
1290 ci->branch1, ci->branch2, &mfi))
1291 return -1;
1292
1293 /*
1294 * FIXME: For rename/add-source conflicts (if we could detect
1295 * such), this is wrong. We should instead find a unique
1296 * pathname and then either rename the add-source file to that
1297 * unique path, or use that unique path instead of src here.
1298 */
1299 if (update_file(o, 0, &mfi.oid, mfi.mode, one->path))
1300 return -1;
1301
1302 /*
1303 * Above, we put the merged content at the merge-base's
1304 * path. Now we usually need to delete both a->path and
1305 * b->path. However, the rename on each side of the merge
1306 * could also be involved in a rename/add conflict. In
1307 * such cases, we should keep the added file around,
1308 * resolving the conflict at that path in its favor.
1309 */
1310 add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1);
1311 if (add) {
1312 if (update_file(o, 0, &add->oid, add->mode, a->path))
1313 return -1;
1314 }
1315 else
1316 remove_file_from_cache(a->path);
1317 add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1);
1318 if (add) {
1319 if (update_file(o, 0, &add->oid, add->mode, b->path))
1320 return -1;
1321 }
1322 else
1323 remove_file_from_cache(b->path);
1324 } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci))
1325 return -1;
1326
1327 return 0;
1328}
1329
1330static int conflict_rename_rename_2to1(struct merge_options *o,
1331 struct rename_conflict_info *ci)
1332{
1333 /* Two files, a & b, were renamed to the same thing, c. */
1334 struct diff_filespec *a = ci->pair1->one;
1335 struct diff_filespec *b = ci->pair2->one;
1336 struct diff_filespec *c1 = ci->pair1->two;
1337 struct diff_filespec *c2 = ci->pair2->two;
1338 char *path = c1->path; /* == c2->path */
1339 struct merge_file_info mfi_c1;
1340 struct merge_file_info mfi_c2;
1341 int ret;
1342
1343 output(o, 1, _("CONFLICT (rename/rename): "
1344 "Rename %s->%s in %s. "
1345 "Rename %s->%s in %s"),
1346 a->path, c1->path, ci->branch1,
1347 b->path, c2->path, ci->branch2);
1348
1349 remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path));
1350 remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path));
1351
1352 if (merge_file_special_markers(o, a, c1, &ci->ren1_other,
1353 o->branch1, c1->path,
1354 o->branch2, ci->ren1_other.path, &mfi_c1) ||
1355 merge_file_special_markers(o, b, &ci->ren2_other, c2,
1356 o->branch1, ci->ren2_other.path,
1357 o->branch2, c2->path, &mfi_c2))
1358 return -1;
1359
1360 if (o->call_depth) {
1361 /*
1362 * If mfi_c1.clean && mfi_c2.clean, then it might make
1363 * sense to do a two-way merge of those results. But, I
1364 * think in all cases, it makes sense to have the virtual
1365 * merge base just undo the renames; they can be detected
1366 * again later for the non-recursive merge.
1367 */
1368 remove_file(o, 0, path, 0);
1369 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path);
1370 if (!ret)
1371 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1372 b->path);
1373 } else {
1374 char *new_path1 = unique_path(o, path, ci->branch1);
1375 char *new_path2 = unique_path(o, path, ci->branch2);
1376 output(o, 1, _("Renaming %s to %s and %s to %s instead"),
1377 a->path, new_path1, b->path, new_path2);
1378 remove_file(o, 0, path, 0);
1379 ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1);
1380 if (!ret)
1381 ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode,
1382 new_path2);
1383 free(new_path2);
1384 free(new_path1);
1385 }
1386
1387 return ret;
1388}
1389
1390/*
1391 * Get the diff_filepairs changed between o_tree and tree.
1392 */
1393static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
1394 struct tree *o_tree,
1395 struct tree *tree)
1396{
1397 struct diff_queue_struct *ret;
1398 struct diff_options opts;
1399
1400 diff_setup(&opts);
1401 opts.flags.recursive = 1;
1402 opts.flags.rename_empty = 0;
1403 opts.detect_rename = DIFF_DETECT_RENAME;
1404 opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
1405 o->diff_rename_limit >= 0 ? o->diff_rename_limit :
1406 1000;
1407 opts.rename_score = o->rename_score;
1408 opts.show_rename_progress = o->show_rename_progress;
1409 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1410 diff_setup_done(&opts);
1411 diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
1412 diffcore_std(&opts);
1413 if (opts.needed_rename_limit > o->needed_rename_limit)
1414 o->needed_rename_limit = opts.needed_rename_limit;
1415
1416 ret = xmalloc(sizeof(*ret));
1417 *ret = diff_queued_diff;
1418
1419 opts.output_format = DIFF_FORMAT_NO_OUTPUT;
1420 diff_queued_diff.nr = 0;
1421 diff_queued_diff.queue = NULL;
1422 diff_flush(&opts);
1423 return ret;
1424}
1425
1426static int tree_has_path(struct tree *tree, const char *path)
1427{
1428 unsigned char hashy[GIT_MAX_RAWSZ];
1429 unsigned int mode_o;
1430
1431 return !get_tree_entry(tree->object.oid.hash, path,
1432 hashy, &mode_o);
1433}
1434
1435/*
1436 * Return a new string that replaces the beginning portion (which matches
1437 * entry->dir), with entry->new_dir. In perl-speak:
1438 * new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
1439 * NOTE:
1440 * Caller must ensure that old_path starts with entry->dir + '/'.
1441 */
1442static char *apply_dir_rename(struct dir_rename_entry *entry,
1443 const char *old_path)
1444{
1445 struct strbuf new_path = STRBUF_INIT;
1446 int oldlen, newlen;
1447
1448 if (entry->non_unique_new_dir)
1449 return NULL;
1450
1451 oldlen = strlen(entry->dir);
1452 newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
1453 strbuf_grow(&new_path, newlen);
1454 strbuf_addbuf(&new_path, &entry->new_dir);
1455 strbuf_addstr(&new_path, &old_path[oldlen]);
1456
1457 return strbuf_detach(&new_path, NULL);
1458}
1459
1460static void get_renamed_dir_portion(const char *old_path, const char *new_path,
1461 char **old_dir, char **new_dir)
1462{
1463 char *end_of_old, *end_of_new;
1464 int old_len, new_len;
1465
1466 *old_dir = NULL;
1467 *new_dir = NULL;
1468
1469 /*
1470 * For
1471 * "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
1472 * the "e/foo.c" part is the same, we just want to know that
1473 * "a/b/c/d" was renamed to "a/b/some/thing/else"
1474 * so, for this example, this function returns "a/b/c/d" in
1475 * *old_dir and "a/b/some/thing/else" in *new_dir.
1476 *
1477 * Also, if the basename of the file changed, we don't care. We
1478 * want to know which portion of the directory, if any, changed.
1479 */
1480 end_of_old = strrchr(old_path, '/');
1481 end_of_new = strrchr(new_path, '/');
1482
1483 if (end_of_old == NULL || end_of_new == NULL)
1484 return;
1485 while (*--end_of_new == *--end_of_old &&
1486 end_of_old != old_path &&
1487 end_of_new != new_path)
1488 ; /* Do nothing; all in the while loop */
1489 /*
1490 * We've found the first non-matching character in the directory
1491 * paths. That means the current directory we were comparing
1492 * represents the rename. Move end_of_old and end_of_new back
1493 * to the full directory name.
1494 */
1495 if (*end_of_old == '/')
1496 end_of_old++;
1497 if (*end_of_old != '/')
1498 end_of_new++;
1499 end_of_old = strchr(end_of_old, '/');
1500 end_of_new = strchr(end_of_new, '/');
1501
1502 /*
1503 * It may have been the case that old_path and new_path were the same
1504 * directory all along. Don't claim a rename if they're the same.
1505 */
1506 old_len = end_of_old - old_path;
1507 new_len = end_of_new - new_path;
1508
1509 if (old_len != new_len || strncmp(old_path, new_path, old_len)) {
1510 *old_dir = xstrndup(old_path, old_len);
1511 *new_dir = xstrndup(new_path, new_len);
1512 }
1513}
1514
1515static void remove_hashmap_entries(struct hashmap *dir_renames,
1516 struct string_list *items_to_remove)
1517{
1518 int i;
1519 struct dir_rename_entry *entry;
1520
1521 for (i = 0; i < items_to_remove->nr; i++) {
1522 entry = items_to_remove->items[i].util;
1523 hashmap_remove(dir_renames, entry, NULL);
1524 }
1525 string_list_clear(items_to_remove, 0);
1526}
1527
1528/*
1529 * See if there is a directory rename for path, and if there are any file
1530 * level conflicts for the renamed location. If there is a rename and
1531 * there are no conflicts, return the new name. Otherwise, return NULL.
1532 */
1533static char *handle_path_level_conflicts(struct merge_options *o,
1534 const char *path,
1535 struct dir_rename_entry *entry,
1536 struct hashmap *collisions,
1537 struct tree *tree)
1538{
1539 char *new_path = NULL;
1540 struct collision_entry *collision_ent;
1541 int clean = 1;
1542 struct strbuf collision_paths = STRBUF_INIT;
1543
1544 /*
1545 * entry has the mapping of old directory name to new directory name
1546 * that we want to apply to path.
1547 */
1548 new_path = apply_dir_rename(entry, path);
1549
1550 if (!new_path) {
1551 /* This should only happen when entry->non_unique_new_dir set */
1552 if (!entry->non_unique_new_dir)
1553 BUG("entry->non_unqiue_dir not set and !new_path");
1554 output(o, 1, _("CONFLICT (directory rename split): "
1555 "Unclear where to place %s because directory "
1556 "%s was renamed to multiple other directories, "
1557 "with no destination getting a majority of the "
1558 "files."),
1559 path, entry->dir);
1560 clean = 0;
1561 return NULL;
1562 }
1563
1564 /*
1565 * The caller needs to have ensured that it has pre-populated
1566 * collisions with all paths that map to new_path. Do a quick check
1567 * to ensure that's the case.
1568 */
1569 collision_ent = collision_find_entry(collisions, new_path);
1570 if (collision_ent == NULL)
1571 BUG("collision_ent is NULL");
1572
1573 /*
1574 * Check for one-sided add/add/.../add conflicts, i.e.
1575 * where implicit renames from the other side doing
1576 * directory rename(s) can affect this side of history
1577 * to put multiple paths into the same location. Warn
1578 * and bail on directory renames for such paths.
1579 */
1580 if (collision_ent->reported_already) {
1581 clean = 0;
1582 } else if (tree_has_path(tree, new_path)) {
1583 collision_ent->reported_already = 1;
1584 strbuf_add_separated_string_list(&collision_paths, ", ",
1585 &collision_ent->source_files);
1586 output(o, 1, _("CONFLICT (implicit dir rename): Existing "
1587 "file/dir at %s in the way of implicit "
1588 "directory rename(s) putting the following "
1589 "path(s) there: %s."),
1590 new_path, collision_paths.buf);
1591 clean = 0;
1592 } else if (collision_ent->source_files.nr > 1) {
1593 collision_ent->reported_already = 1;
1594 strbuf_add_separated_string_list(&collision_paths, ", ",
1595 &collision_ent->source_files);
1596 output(o, 1, _("CONFLICT (implicit dir rename): Cannot map "
1597 "more than one path to %s; implicit directory "
1598 "renames tried to put these paths there: %s"),
1599 new_path, collision_paths.buf);
1600 clean = 0;
1601 }
1602
1603 /* Free memory we no longer need */
1604 strbuf_release(&collision_paths);
1605 if (!clean && new_path) {
1606 free(new_path);
1607 return NULL;
1608 }
1609
1610 return new_path;
1611}
1612
1613/*
1614 * There are a couple things we want to do at the directory level:
1615 * 1. Check for both sides renaming to the same thing, in order to avoid
1616 * implicit renaming of files that should be left in place. (See
1617 * testcase 6b in t6043 for details.)
1618 * 2. Prune directory renames if there are still files left in the
1619 * the original directory. These represent a partial directory rename,
1620 * i.e. a rename where only some of the files within the directory
1621 * were renamed elsewhere. (Technically, this could be done earlier
1622 * in get_directory_renames(), except that would prevent us from
1623 * doing the previous check and thus failing testcase 6b.)
1624 * 3. Check for rename/rename(1to2) conflicts (at the directory level).
1625 * In the future, we could potentially record this info as well and
1626 * omit reporting rename/rename(1to2) conflicts for each path within
1627 * the affected directories, thus cleaning up the merge output.
1628 * NOTE: We do NOT check for rename/rename(2to1) conflicts at the
1629 * directory level, because merging directories is fine. If it
1630 * causes conflicts for files within those merged directories, then
1631 * that should be detected at the individual path level.
1632 */
1633static void handle_directory_level_conflicts(struct merge_options *o,
1634 struct hashmap *dir_re_head,
1635 struct tree *head,
1636 struct hashmap *dir_re_merge,
1637 struct tree *merge)
1638{
1639 struct hashmap_iter iter;
1640 struct dir_rename_entry *head_ent;
1641 struct dir_rename_entry *merge_ent;
1642
1643 struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
1644 struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
1645
1646 hashmap_iter_init(dir_re_head, &iter);
1647 while ((head_ent = hashmap_iter_next(&iter))) {
1648 merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
1649 if (merge_ent &&
1650 !head_ent->non_unique_new_dir &&
1651 !merge_ent->non_unique_new_dir &&
1652 !strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
1653 /* 1. Renamed identically; remove it from both sides */
1654 string_list_append(&remove_from_head,
1655 head_ent->dir)->util = head_ent;
1656 strbuf_release(&head_ent->new_dir);
1657 string_list_append(&remove_from_merge,
1658 merge_ent->dir)->util = merge_ent;
1659 strbuf_release(&merge_ent->new_dir);
1660 } else if (tree_has_path(head, head_ent->dir)) {
1661 /* 2. This wasn't a directory rename after all */
1662 string_list_append(&remove_from_head,
1663 head_ent->dir)->util = head_ent;
1664 strbuf_release(&head_ent->new_dir);
1665 }
1666 }
1667
1668 remove_hashmap_entries(dir_re_head, &remove_from_head);
1669 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
1670
1671 hashmap_iter_init(dir_re_merge, &iter);
1672 while ((merge_ent = hashmap_iter_next(&iter))) {
1673 head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
1674 if (tree_has_path(merge, merge_ent->dir)) {
1675 /* 2. This wasn't a directory rename after all */
1676 string_list_append(&remove_from_merge,
1677 merge_ent->dir)->util = merge_ent;
1678 } else if (head_ent &&
1679 !head_ent->non_unique_new_dir &&
1680 !merge_ent->non_unique_new_dir) {
1681 /* 3. rename/rename(1to2) */
1682 /*
1683 * We can assume it's not rename/rename(1to1) because
1684 * that was case (1), already checked above. So we
1685 * know that head_ent->new_dir and merge_ent->new_dir
1686 * are different strings.
1687 */
1688 output(o, 1, _("CONFLICT (rename/rename): "
1689 "Rename directory %s->%s in %s. "
1690 "Rename directory %s->%s in %s"),
1691 head_ent->dir, head_ent->new_dir.buf, o->branch1,
1692 head_ent->dir, merge_ent->new_dir.buf, o->branch2);
1693 string_list_append(&remove_from_head,
1694 head_ent->dir)->util = head_ent;
1695 strbuf_release(&head_ent->new_dir);
1696 string_list_append(&remove_from_merge,
1697 merge_ent->dir)->util = merge_ent;
1698 strbuf_release(&merge_ent->new_dir);
1699 }
1700 }
1701
1702 remove_hashmap_entries(dir_re_head, &remove_from_head);
1703 remove_hashmap_entries(dir_re_merge, &remove_from_merge);
1704}
1705
1706static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
1707 struct tree *tree)
1708{
1709 struct hashmap *dir_renames;
1710 struct hashmap_iter iter;
1711 struct dir_rename_entry *entry;
1712 int i;
1713
1714 /*
1715 * Typically, we think of a directory rename as all files from a
1716 * certain directory being moved to a target directory. However,
1717 * what if someone first moved two files from the original
1718 * directory in one commit, and then renamed the directory
1719 * somewhere else in a later commit? At merge time, we just know
1720 * that files from the original directory went to two different
1721 * places, and that the bulk of them ended up in the same place.
1722 * We want each directory rename to represent where the bulk of the
1723 * files from that directory end up; this function exists to find
1724 * where the bulk of the files went.
1725 *
1726 * The first loop below simply iterates through the list of file
1727 * renames, finding out how often each directory rename pair
1728 * possibility occurs.
1729 */
1730 dir_renames = xmalloc(sizeof(struct hashmap));
1731 dir_rename_init(dir_renames);
1732 for (i = 0; i < pairs->nr; ++i) {
1733 struct string_list_item *item;
1734 int *count;
1735 struct diff_filepair *pair = pairs->queue[i];
1736 char *old_dir, *new_dir;
1737
1738 /* File not part of directory rename if it wasn't renamed */
1739 if (pair->status != 'R')
1740 continue;
1741
1742 get_renamed_dir_portion(pair->one->path, pair->two->path,
1743 &old_dir, &new_dir);
1744 if (!old_dir)
1745 /* Directory didn't change at all; ignore this one. */
1746 continue;
1747
1748 entry = dir_rename_find_entry(dir_renames, old_dir);
1749 if (!entry) {
1750 entry = xmalloc(sizeof(struct dir_rename_entry));
1751 dir_rename_entry_init(entry, old_dir);
1752 hashmap_put(dir_renames, entry);
1753 } else {
1754 free(old_dir);
1755 }
1756 item = string_list_lookup(&entry->possible_new_dirs, new_dir);
1757 if (!item) {
1758 item = string_list_insert(&entry->possible_new_dirs,
1759 new_dir);
1760 item->util = xcalloc(1, sizeof(int));
1761 } else {
1762 free(new_dir);
1763 }
1764 count = item->util;
1765 *count += 1;
1766 }
1767
1768 /*
1769 * For each directory with files moved out of it, we find out which
1770 * target directory received the most files so we can declare it to
1771 * be the "winning" target location for the directory rename. This
1772 * winner gets recorded in new_dir. If there is no winner
1773 * (multiple target directories received the same number of files),
1774 * we set non_unique_new_dir. Once we've determined the winner (or
1775 * that there is no winner), we no longer need possible_new_dirs.
1776 */
1777 hashmap_iter_init(dir_renames, &iter);
1778 while ((entry = hashmap_iter_next(&iter))) {
1779 int max = 0;
1780 int bad_max = 0;
1781 char *best = NULL;
1782
1783 for (i = 0; i < entry->possible_new_dirs.nr; i++) {
1784 int *count = entry->possible_new_dirs.items[i].util;
1785
1786 if (*count == max)
1787 bad_max = max;
1788 else if (*count > max) {
1789 max = *count;
1790 best = entry->possible_new_dirs.items[i].string;
1791 }
1792 }
1793 if (bad_max == max)
1794 entry->non_unique_new_dir = 1;
1795 else {
1796 assert(entry->new_dir.len == 0);
1797 strbuf_addstr(&entry->new_dir, best);
1798 }
1799 /*
1800 * The relevant directory sub-portion of the original full
1801 * filepaths were xstrndup'ed before inserting into
1802 * possible_new_dirs, and instead of manually iterating the
1803 * list and free'ing each, just lie and tell
1804 * possible_new_dirs that it did the strdup'ing so that it
1805 * will free them for us.
1806 */
1807 entry->possible_new_dirs.strdup_strings = 1;
1808 string_list_clear(&entry->possible_new_dirs, 1);
1809 }
1810
1811 return dir_renames;
1812}
1813
1814static struct dir_rename_entry *check_dir_renamed(const char *path,
1815 struct hashmap *dir_renames)
1816{
1817 char temp[PATH_MAX];
1818 char *end;
1819 struct dir_rename_entry *entry;
1820
1821 strcpy(temp, path);
1822 while ((end = strrchr(temp, '/'))) {
1823 *end = '\0';
1824 entry = dir_rename_find_entry(dir_renames, temp);
1825 if (entry)
1826 return entry;
1827 }
1828 return NULL;
1829}
1830
1831static void compute_collisions(struct hashmap *collisions,
1832 struct hashmap *dir_renames,
1833 struct diff_queue_struct *pairs)
1834{
1835 int i;
1836
1837 /*
1838 * Multiple files can be mapped to the same path due to directory
1839 * renames done by the other side of history. Since that other
1840 * side of history could have merged multiple directories into one,
1841 * if our side of history added the same file basename to each of
1842 * those directories, then all N of them would get implicitly
1843 * renamed by the directory rename detection into the same path,
1844 * and we'd get an add/add/.../add conflict, and all those adds
1845 * from *this* side of history. This is not representable in the
1846 * index, and users aren't going to easily be able to make sense of
1847 * it. So we need to provide a good warning about what's
1848 * happening, and fall back to no-directory-rename detection
1849 * behavior for those paths.
1850 *
1851 * See testcases 9e and all of section 5 from t6043 for examples.
1852 */
1853 collision_init(collisions);
1854
1855 for (i = 0; i < pairs->nr; ++i) {
1856 struct dir_rename_entry *dir_rename_ent;
1857 struct collision_entry *collision_ent;
1858 char *new_path;
1859 struct diff_filepair *pair = pairs->queue[i];
1860
1861 if (pair->status == 'D')
1862 continue;
1863 dir_rename_ent = check_dir_renamed(pair->two->path,
1864 dir_renames);
1865 if (!dir_rename_ent)
1866 continue;
1867
1868 new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
1869 if (!new_path)
1870 /*
1871 * dir_rename_ent->non_unique_new_path is true, which
1872 * means there is no directory rename for us to use,
1873 * which means it won't cause us any additional
1874 * collisions.
1875 */
1876 continue;
1877 collision_ent = collision_find_entry(collisions, new_path);
1878 if (!collision_ent) {
1879 collision_ent = xcalloc(1,
1880 sizeof(struct collision_entry));
1881 hashmap_entry_init(collision_ent, strhash(new_path));
1882 hashmap_put(collisions, collision_ent);
1883 collision_ent->target_file = new_path;
1884 } else {
1885 free(new_path);
1886 }
1887 string_list_insert(&collision_ent->source_files,
1888 pair->two->path);
1889 }
1890}
1891
1892static char *check_for_directory_rename(struct merge_options *o,
1893 const char *path,
1894 struct tree *tree,
1895 struct hashmap *dir_renames,
1896 struct hashmap *dir_rename_exclusions,
1897 struct hashmap *collisions,
1898 int *clean_merge)
1899{
1900 char *new_path = NULL;
1901 struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
1902 struct dir_rename_entry *oentry = NULL;
1903
1904 if (!entry)
1905 return new_path;
1906
1907 /*
1908 * This next part is a little weird. We do not want to do an
1909 * implicit rename into a directory we renamed on our side, because
1910 * that will result in a spurious rename/rename(1to2) conflict. An
1911 * example:
1912 * Base commit: dumbdir/afile, otherdir/bfile
1913 * Side 1: smrtdir/afile, otherdir/bfile
1914 * Side 2: dumbdir/afile, dumbdir/bfile
1915 * Here, while working on Side 1, we could notice that otherdir was
1916 * renamed/merged to dumbdir, and change the diff_filepair for
1917 * otherdir/bfile into a rename into dumbdir/bfile. However, Side
1918 * 2 will notice the rename from dumbdir to smrtdir, and do the
1919 * transitive rename to move it from dumbdir/bfile to
1920 * smrtdir/bfile. That gives us bfile in dumbdir vs being in
1921 * smrtdir, a rename/rename(1to2) conflict. We really just want
1922 * the file to end up in smrtdir. And the way to achieve that is
1923 * to not let Side1 do the rename to dumbdir, since we know that is
1924 * the source of one of our directory renames.
1925 *
1926 * That's why oentry and dir_rename_exclusions is here.
1927 *
1928 * As it turns out, this also prevents N-way transient rename
1929 * confusion; See testcases 9c and 9d of t6043.
1930 */
1931 oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
1932 if (oentry) {
1933 output(o, 1, _("WARNING: Avoiding applying %s -> %s rename "
1934 "to %s, because %s itself was renamed."),
1935 entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
1936 } else {
1937 new_path = handle_path_level_conflicts(o, path, entry,
1938 collisions, tree);
1939 *clean_merge &= (new_path != NULL);
1940 }
1941
1942 return new_path;
1943}
1944
1945/*
1946 * Get information of all renames which occurred in 'pairs', making use of
1947 * any implicit directory renames inferred from the other side of history.
1948 * We need the three trees in the merge ('o_tree', 'a_tree' and 'b_tree')
1949 * to be able to associate the correct cache entries with the rename
1950 * information; tree is always equal to either a_tree or b_tree.
1951 */
1952static struct string_list *get_renames(struct merge_options *o,
1953 struct diff_queue_struct *pairs,
1954 struct hashmap *dir_renames,
1955 struct hashmap *dir_rename_exclusions,
1956 struct tree *tree,
1957 struct tree *o_tree,
1958 struct tree *a_tree,
1959 struct tree *b_tree,
1960 struct string_list *entries,
1961 int *clean_merge)
1962{
1963 int i;
1964 struct hashmap collisions;
1965 struct hashmap_iter iter;
1966 struct collision_entry *e;
1967 struct string_list *renames;
1968
1969 compute_collisions(&collisions, dir_renames, pairs);
1970 renames = xcalloc(1, sizeof(struct string_list));
1971
1972 for (i = 0; i < pairs->nr; ++i) {
1973 struct string_list_item *item;
1974 struct rename *re;
1975 struct diff_filepair *pair = pairs->queue[i];
1976 char *new_path; /* non-NULL only with directory renames */
1977
1978 if (pair->status == 'D') {
1979 diff_free_filepair(pair);
1980 continue;
1981 }
1982 new_path = check_for_directory_rename(o, pair->two->path, tree,
1983 dir_renames,
1984 dir_rename_exclusions,
1985 &collisions,
1986 clean_merge);
1987 if (pair->status != 'R' && !new_path) {
1988 diff_free_filepair(pair);
1989 continue;
1990 }
1991
1992 re = xmalloc(sizeof(*re));
1993 re->processed = 0;
1994 re->pair = pair;
1995 item = string_list_lookup(entries, re->pair->one->path);
1996 if (!item)
1997 re->src_entry = insert_stage_data(re->pair->one->path,
1998 o_tree, a_tree, b_tree, entries);
1999 else
2000 re->src_entry = item->util;
2001
2002 item = string_list_lookup(entries, re->pair->two->path);
2003 if (!item)
2004 re->dst_entry = insert_stage_data(re->pair->two->path,
2005 o_tree, a_tree, b_tree, entries);
2006 else
2007 re->dst_entry = item->util;
2008 item = string_list_insert(renames, pair->one->path);
2009 item->util = re;
2010 }
2011
2012 hashmap_iter_init(&collisions, &iter);
2013 while ((e = hashmap_iter_next(&iter))) {
2014 free(e->target_file);
2015 string_list_clear(&e->source_files, 0);
2016 }
2017 hashmap_free(&collisions, 1);
2018 return renames;
2019}
2020
2021static int process_renames(struct merge_options *o,
2022 struct string_list *a_renames,
2023 struct string_list *b_renames)
2024{
2025 int clean_merge = 1, i, j;
2026 struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
2027 struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
2028 const struct rename *sre;
2029
2030 for (i = 0; i < a_renames->nr; i++) {
2031 sre = a_renames->items[i].util;
2032 string_list_insert(&a_by_dst, sre->pair->two->path)->util
2033 = (void *)sre;
2034 }
2035 for (i = 0; i < b_renames->nr; i++) {
2036 sre = b_renames->items[i].util;
2037 string_list_insert(&b_by_dst, sre->pair->two->path)->util
2038 = (void *)sre;
2039 }
2040
2041 for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
2042 struct string_list *renames1, *renames2Dst;
2043 struct rename *ren1 = NULL, *ren2 = NULL;
2044 const char *branch1, *branch2;
2045 const char *ren1_src, *ren1_dst;
2046 struct string_list_item *lookup;
2047
2048 if (i >= a_renames->nr) {
2049 ren2 = b_renames->items[j++].util;
2050 } else if (j >= b_renames->nr) {
2051 ren1 = a_renames->items[i++].util;
2052 } else {
2053 int compare = strcmp(a_renames->items[i].string,
2054 b_renames->items[j].string);
2055 if (compare <= 0)
2056 ren1 = a_renames->items[i++].util;
2057 if (compare >= 0)
2058 ren2 = b_renames->items[j++].util;
2059 }
2060
2061 /* TODO: refactor, so that 1/2 are not needed */
2062 if (ren1) {
2063 renames1 = a_renames;
2064 renames2Dst = &b_by_dst;
2065 branch1 = o->branch1;
2066 branch2 = o->branch2;
2067 } else {
2068 renames1 = b_renames;
2069 renames2Dst = &a_by_dst;
2070 branch1 = o->branch2;
2071 branch2 = o->branch1;
2072 SWAP(ren2, ren1);
2073 }
2074
2075 if (ren1->processed)
2076 continue;
2077 ren1->processed = 1;
2078 ren1->dst_entry->processed = 1;
2079 /* BUG: We should only mark src_entry as processed if we
2080 * are not dealing with a rename + add-source case.
2081 */
2082 ren1->src_entry->processed = 1;
2083
2084 ren1_src = ren1->pair->one->path;
2085 ren1_dst = ren1->pair->two->path;
2086
2087 if (ren2) {
2088 /* One file renamed on both sides */
2089 const char *ren2_src = ren2->pair->one->path;
2090 const char *ren2_dst = ren2->pair->two->path;
2091 enum rename_type rename_type;
2092 if (strcmp(ren1_src, ren2_src) != 0)
2093 die("BUG: ren1_src != ren2_src");
2094 ren2->dst_entry->processed = 1;
2095 ren2->processed = 1;
2096 if (strcmp(ren1_dst, ren2_dst) != 0) {
2097 rename_type = RENAME_ONE_FILE_TO_TWO;
2098 clean_merge = 0;
2099 } else {
2100 rename_type = RENAME_ONE_FILE_TO_ONE;
2101 /* BUG: We should only remove ren1_src in
2102 * the base stage (think of rename +
2103 * add-source cases).
2104 */
2105 remove_file(o, 1, ren1_src, 1);
2106 update_entry(ren1->dst_entry,
2107 ren1->pair->one,
2108 ren1->pair->two,
2109 ren2->pair->two);
2110 }
2111 setup_rename_conflict_info(rename_type,
2112 ren1->pair,
2113 ren2->pair,
2114 branch1,
2115 branch2,
2116 ren1->dst_entry,
2117 ren2->dst_entry,
2118 o,
2119 NULL,
2120 NULL);
2121 } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
2122 /* Two different files renamed to the same thing */
2123 char *ren2_dst;
2124 ren2 = lookup->util;
2125 ren2_dst = ren2->pair->two->path;
2126 if (strcmp(ren1_dst, ren2_dst) != 0)
2127 die("BUG: ren1_dst != ren2_dst");
2128
2129 clean_merge = 0;
2130 ren2->processed = 1;
2131 /*
2132 * BUG: We should only mark src_entry as processed
2133 * if we are not dealing with a rename + add-source
2134 * case.
2135 */
2136 ren2->src_entry->processed = 1;
2137
2138 setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
2139 ren1->pair,
2140 ren2->pair,
2141 branch1,
2142 branch2,
2143 ren1->dst_entry,
2144 ren2->dst_entry,
2145 o,
2146 ren1->src_entry,
2147 ren2->src_entry);
2148
2149 } else {
2150 /* Renamed in 1, maybe changed in 2 */
2151 /* we only use sha1 and mode of these */
2152 struct diff_filespec src_other, dst_other;
2153 int try_merge;
2154
2155 /*
2156 * unpack_trees loads entries from common-commit
2157 * into stage 1, from head-commit into stage 2, and
2158 * from merge-commit into stage 3. We keep track
2159 * of which side corresponds to the rename.
2160 */
2161 int renamed_stage = a_renames == renames1 ? 2 : 3;
2162 int other_stage = a_renames == renames1 ? 3 : 2;
2163
2164 /* BUG: We should only remove ren1_src in the base
2165 * stage and in other_stage (think of rename +
2166 * add-source case).
2167 */
2168 remove_file(o, 1, ren1_src,
2169 renamed_stage == 2 || !was_tracked(ren1_src));
2170
2171 oidcpy(&src_other.oid,
2172 &ren1->src_entry->stages[other_stage].oid);
2173 src_other.mode = ren1->src_entry->stages[other_stage].mode;
2174 oidcpy(&dst_other.oid,
2175 &ren1->dst_entry->stages[other_stage].oid);
2176 dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
2177 try_merge = 0;
2178
2179 if (oid_eq(&src_other.oid, &null_oid)) {
2180 setup_rename_conflict_info(RENAME_DELETE,
2181 ren1->pair,
2182 NULL,
2183 branch1,
2184 branch2,
2185 ren1->dst_entry,
2186 NULL,
2187 o,
2188 NULL,
2189 NULL);
2190 } else if ((dst_other.mode == ren1->pair->two->mode) &&
2191 oid_eq(&dst_other.oid, &ren1->pair->two->oid)) {
2192 /*
2193 * Added file on the other side identical to
2194 * the file being renamed: clean merge.
2195 * Also, there is no need to overwrite the
2196 * file already in the working copy, so call
2197 * update_file_flags() instead of
2198 * update_file().
2199 */
2200 if (update_file_flags(o,
2201 &ren1->pair->two->oid,
2202 ren1->pair->two->mode,
2203 ren1_dst,
2204 1, /* update_cache */
2205 0 /* update_wd */))
2206 clean_merge = -1;
2207 } else if (!oid_eq(&dst_other.oid, &null_oid)) {
2208 clean_merge = 0;
2209 try_merge = 1;
2210 output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. "
2211 "%s added in %s"),
2212 ren1_src, ren1_dst, branch1,
2213 ren1_dst, branch2);
2214 if (o->call_depth) {
2215 struct merge_file_info mfi;
2216 if (merge_file_one(o, ren1_dst, &null_oid, 0,
2217 &ren1->pair->two->oid,
2218 ren1->pair->two->mode,
2219 &dst_other.oid,
2220 dst_other.mode,
2221 branch1, branch2, &mfi)) {
2222 clean_merge = -1;
2223 goto cleanup_and_return;
2224 }
2225 output(o, 1, _("Adding merged %s"), ren1_dst);
2226 if (update_file(o, 0, &mfi.oid,
2227 mfi.mode, ren1_dst))
2228 clean_merge = -1;
2229 try_merge = 0;
2230 } else {
2231 char *new_path = unique_path(o, ren1_dst, branch2);
2232 output(o, 1, _("Adding as %s instead"), new_path);
2233 if (update_file(o, 0, &dst_other.oid,
2234 dst_other.mode, new_path))
2235 clean_merge = -1;
2236 free(new_path);
2237 }
2238 } else
2239 try_merge = 1;
2240
2241 if (clean_merge < 0)
2242 goto cleanup_and_return;
2243 if (try_merge) {
2244 struct diff_filespec *one, *a, *b;
2245 src_other.path = (char *)ren1_src;
2246
2247 one = ren1->pair->one;
2248 if (a_renames == renames1) {
2249 a = ren1->pair->two;
2250 b = &src_other;
2251 } else {
2252 b = ren1->pair->two;
2253 a = &src_other;
2254 }
2255 update_entry(ren1->dst_entry, one, a, b);
2256 setup_rename_conflict_info(RENAME_NORMAL,
2257 ren1->pair,
2258 NULL,
2259 branch1,
2260 NULL,
2261 ren1->dst_entry,
2262 NULL,
2263 o,
2264 NULL,
2265 NULL);
2266 }
2267 }
2268 }
2269cleanup_and_return:
2270 string_list_clear(&a_by_dst, 0);
2271 string_list_clear(&b_by_dst, 0);
2272
2273 return clean_merge;
2274}
2275
2276struct rename_info {
2277 struct string_list *head_renames;
2278 struct string_list *merge_renames;
2279};
2280
2281static void initial_cleanup_rename(struct diff_queue_struct *pairs,
2282 struct hashmap *dir_renames)
2283{
2284 struct hashmap_iter iter;
2285 struct dir_rename_entry *e;
2286
2287 hashmap_iter_init(dir_renames, &iter);
2288 while ((e = hashmap_iter_next(&iter))) {
2289 free(e->dir);
2290 strbuf_release(&e->new_dir);
2291 /* possible_new_dirs already cleared in get_directory_renames */
2292 }
2293 hashmap_free(dir_renames, 1);
2294 free(dir_renames);
2295
2296 free(pairs->queue);
2297 free(pairs);
2298}
2299
2300static int handle_renames(struct merge_options *o,
2301 struct tree *common,
2302 struct tree *head,
2303 struct tree *merge,
2304 struct string_list *entries,
2305 struct rename_info *ri)
2306{
2307 struct diff_queue_struct *head_pairs, *merge_pairs;
2308 struct hashmap *dir_re_head, *dir_re_merge;
2309 int clean = 1;
2310
2311 ri->head_renames = NULL;
2312 ri->merge_renames = NULL;
2313
2314 if (!o->detect_rename)
2315 return 1;
2316
2317 head_pairs = get_diffpairs(o, common, head);
2318 merge_pairs = get_diffpairs(o, common, merge);
2319
2320 dir_re_head = get_directory_renames(head_pairs, head);
2321 dir_re_merge = get_directory_renames(merge_pairs, merge);
2322
2323 handle_directory_level_conflicts(o,
2324 dir_re_head, head,
2325 dir_re_merge, merge);
2326
2327 ri->head_renames = get_renames(o, head_pairs,
2328 dir_re_merge, dir_re_head, head,
2329 common, head, merge, entries,
2330 &clean);
2331 if (clean < 0)
2332 goto cleanup;
2333 ri->merge_renames = get_renames(o, merge_pairs,
2334 dir_re_head, dir_re_merge, merge,
2335 common, head, merge, entries,
2336 &clean);
2337 if (clean < 0)
2338 goto cleanup;
2339 clean &= process_renames(o, ri->head_renames, ri->merge_renames);
2340
2341cleanup:
2342 /*
2343 * Some cleanup is deferred until cleanup_renames() because the
2344 * data structures are still needed and referenced in
2345 * process_entry(). But there are a few things we can free now.
2346 */
2347 initial_cleanup_rename(head_pairs, dir_re_head);
2348 initial_cleanup_rename(merge_pairs, dir_re_merge);
2349
2350 return clean;
2351}
2352
2353static void final_cleanup_rename(struct string_list *rename)
2354{
2355 const struct rename *re;
2356 int i;
2357
2358 if (rename == NULL)
2359 return;
2360
2361 for (i = 0; i < rename->nr; i++) {
2362 re = rename->items[i].util;
2363 diff_free_filepair(re->pair);
2364 }
2365 string_list_clear(rename, 1);
2366 free(rename);
2367}
2368
2369static void final_cleanup_renames(struct rename_info *re_info)
2370{
2371 final_cleanup_rename(re_info->head_renames);
2372 final_cleanup_rename(re_info->merge_renames);
2373}
2374
2375static struct object_id *stage_oid(const struct object_id *oid, unsigned mode)
2376{
2377 return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid;
2378}
2379
2380static int read_oid_strbuf(struct merge_options *o,
2381 const struct object_id *oid, struct strbuf *dst)
2382{
2383 void *buf;
2384 enum object_type type;
2385 unsigned long size;
2386 buf = read_sha1_file(oid->hash, &type, &size);
2387 if (!buf)
2388 return err(o, _("cannot read object %s"), oid_to_hex(oid));
2389 if (type != OBJ_BLOB) {
2390 free(buf);
2391 return err(o, _("object %s is not a blob"), oid_to_hex(oid));
2392 }
2393 strbuf_attach(dst, buf, size, size + 1);
2394 return 0;
2395}
2396
2397static int blob_unchanged(struct merge_options *opt,
2398 const struct object_id *o_oid,
2399 unsigned o_mode,
2400 const struct object_id *a_oid,
2401 unsigned a_mode,
2402 int renormalize, const char *path)
2403{
2404 struct strbuf o = STRBUF_INIT;
2405 struct strbuf a = STRBUF_INIT;
2406 int ret = 0; /* assume changed for safety */
2407
2408 if (a_mode != o_mode)
2409 return 0;
2410 if (oid_eq(o_oid, a_oid))
2411 return 1;
2412 if (!renormalize)
2413 return 0;
2414
2415 assert(o_oid && a_oid);
2416 if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a))
2417 goto error_return;
2418 /*
2419 * Note: binary | is used so that both renormalizations are
2420 * performed. Comparison can be skipped if both files are
2421 * unchanged since their sha1s have already been compared.
2422 */
2423 if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) |
2424 renormalize_buffer(&the_index, path, a.buf, a.len, &a))
2425 ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len));
2426
2427error_return:
2428 strbuf_release(&o);
2429 strbuf_release(&a);
2430 return ret;
2431}
2432
2433static int handle_modify_delete(struct merge_options *o,
2434 const char *path,
2435 struct object_id *o_oid, int o_mode,
2436 struct object_id *a_oid, int a_mode,
2437 struct object_id *b_oid, int b_mode)
2438{
2439 const char *modify_branch, *delete_branch;
2440 struct object_id *changed_oid;
2441 int changed_mode;
2442
2443 if (a_oid) {
2444 modify_branch = o->branch1;
2445 delete_branch = o->branch2;
2446 changed_oid = a_oid;
2447 changed_mode = a_mode;
2448 } else {
2449 modify_branch = o->branch2;
2450 delete_branch = o->branch1;
2451 changed_oid = b_oid;
2452 changed_mode = b_mode;
2453 }
2454
2455 return handle_change_delete(o,
2456 path, NULL,
2457 o_oid, o_mode,
2458 changed_oid, changed_mode,
2459 modify_branch, delete_branch,
2460 _("modify"), _("modified"));
2461}
2462
2463static int merge_content(struct merge_options *o,
2464 const char *path,
2465 struct object_id *o_oid, int o_mode,
2466 struct object_id *a_oid, int a_mode,
2467 struct object_id *b_oid, int b_mode,
2468 struct rename_conflict_info *rename_conflict_info)
2469{
2470 const char *reason = _("content");
2471 const char *path1 = NULL, *path2 = NULL;
2472 struct merge_file_info mfi;
2473 struct diff_filespec one, a, b;
2474 unsigned df_conflict_remains = 0;
2475
2476 if (!o_oid) {
2477 reason = _("add/add");
2478 o_oid = (struct object_id *)&null_oid;
2479 }
2480 one.path = a.path = b.path = (char *)path;
2481 oidcpy(&one.oid, o_oid);
2482 one.mode = o_mode;
2483 oidcpy(&a.oid, a_oid);
2484 a.mode = a_mode;
2485 oidcpy(&b.oid, b_oid);
2486 b.mode = b_mode;
2487
2488 if (rename_conflict_info) {
2489 struct diff_filepair *pair1 = rename_conflict_info->pair1;
2490
2491 path1 = (o->branch1 == rename_conflict_info->branch1) ?
2492 pair1->two->path : pair1->one->path;
2493 /* If rename_conflict_info->pair2 != NULL, we are in
2494 * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a
2495 * normal rename.
2496 */
2497 path2 = (rename_conflict_info->pair2 ||
2498 o->branch2 == rename_conflict_info->branch1) ?
2499 pair1->two->path : pair1->one->path;
2500
2501 if (dir_in_way(path, !o->call_depth,
2502 S_ISGITLINK(pair1->two->mode)))
2503 df_conflict_remains = 1;
2504 }
2505 if (merge_file_special_markers(o, &one, &a, &b,
2506 o->branch1, path1,
2507 o->branch2, path2, &mfi))
2508 return -1;
2509
2510 if (mfi.clean && !df_conflict_remains &&
2511 oid_eq(&mfi.oid, a_oid) && mfi.mode == a_mode) {
2512 int path_renamed_outside_HEAD;
2513 output(o, 3, _("Skipped %s (merged same as existing)"), path);
2514 /*
2515 * The content merge resulted in the same file contents we
2516 * already had. We can return early if those file contents
2517 * are recorded at the correct path (which may not be true
2518 * if the merge involves a rename).
2519 */
2520 path_renamed_outside_HEAD = !path2 || !strcmp(path, path2);
2521 if (!path_renamed_outside_HEAD) {
2522 add_cacheinfo(o, mfi.mode, &mfi.oid, path,
2523 0, (!o->call_depth), 0);
2524 return mfi.clean;
2525 }
2526 } else
2527 output(o, 2, _("Auto-merging %s"), path);
2528
2529 if (!mfi.clean) {
2530 if (S_ISGITLINK(mfi.mode))
2531 reason = _("submodule");
2532 output(o, 1, _("CONFLICT (%s): Merge conflict in %s"),
2533 reason, path);
2534 if (rename_conflict_info && !df_conflict_remains)
2535 if (update_stages(o, path, &one, &a, &b))
2536 return -1;
2537 }
2538
2539 if (df_conflict_remains) {
2540 char *new_path;
2541 if (o->call_depth) {
2542 remove_file_from_cache(path);
2543 } else {
2544 if (!mfi.clean) {
2545 if (update_stages(o, path, &one, &a, &b))
2546 return -1;
2547 } else {
2548 int file_from_stage2 = was_tracked(path);
2549 struct diff_filespec merged;
2550 oidcpy(&merged.oid, &mfi.oid);
2551 merged.mode = mfi.mode;
2552
2553 if (update_stages(o, path, NULL,
2554 file_from_stage2 ? &merged : NULL,
2555 file_from_stage2 ? NULL : &merged))
2556 return -1;
2557 }
2558
2559 }
2560 new_path = unique_path(o, path, rename_conflict_info->branch1);
2561 output(o, 1, _("Adding as %s instead"), new_path);
2562 if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
2563 free(new_path);
2564 return -1;
2565 }
2566 free(new_path);
2567 mfi.clean = 0;
2568 } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
2569 return -1;
2570 return mfi.clean;
2571}
2572
2573/* Per entry merge function */
2574static int process_entry(struct merge_options *o,
2575 const char *path, struct stage_data *entry)
2576{
2577 int clean_merge = 1;
2578 int normalize = o->renormalize;
2579 unsigned o_mode = entry->stages[1].mode;
2580 unsigned a_mode = entry->stages[2].mode;
2581 unsigned b_mode = entry->stages[3].mode;
2582 struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode);
2583 struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode);
2584 struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode);
2585
2586 entry->processed = 1;
2587 if (entry->rename_conflict_info) {
2588 struct rename_conflict_info *conflict_info = entry->rename_conflict_info;
2589 switch (conflict_info->rename_type) {
2590 case RENAME_NORMAL:
2591 case RENAME_ONE_FILE_TO_ONE:
2592 clean_merge = merge_content(o, path,
2593 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
2594 conflict_info);
2595 break;
2596 case RENAME_DELETE:
2597 clean_merge = 0;
2598 if (conflict_rename_delete(o,
2599 conflict_info->pair1,
2600 conflict_info->branch1,
2601 conflict_info->branch2))
2602 clean_merge = -1;
2603 break;
2604 case RENAME_ONE_FILE_TO_TWO:
2605 clean_merge = 0;
2606 if (conflict_rename_rename_1to2(o, conflict_info))
2607 clean_merge = -1;
2608 break;
2609 case RENAME_TWO_FILES_TO_ONE:
2610 clean_merge = 0;
2611 if (conflict_rename_rename_2to1(o, conflict_info))
2612 clean_merge = -1;
2613 break;
2614 default:
2615 entry->processed = 0;
2616 break;
2617 }
2618 } else if (o_oid && (!a_oid || !b_oid)) {
2619 /* Case A: Deleted in one */
2620 if ((!a_oid && !b_oid) ||
2621 (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) ||
2622 (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) {
2623 /* Deleted in both or deleted in one and
2624 * unchanged in the other */
2625 if (a_oid)
2626 output(o, 2, _("Removing %s"), path);
2627 /* do not touch working file if it did not exist */
2628 remove_file(o, 1, path, !a_oid);
2629 } else {
2630 /* Modify/delete; deleted side may have put a directory in the way */
2631 clean_merge = 0;
2632 if (handle_modify_delete(o, path, o_oid, o_mode,
2633 a_oid, a_mode, b_oid, b_mode))
2634 clean_merge = -1;
2635 }
2636 } else if ((!o_oid && a_oid && !b_oid) ||
2637 (!o_oid && !a_oid && b_oid)) {
2638 /* Case B: Added in one. */
2639 /* [nothing|directory] -> ([nothing|directory], file) */
2640
2641 const char *add_branch;
2642 const char *other_branch;
2643 unsigned mode;
2644 const struct object_id *oid;
2645 const char *conf;
2646
2647 if (a_oid) {
2648 add_branch = o->branch1;
2649 other_branch = o->branch2;
2650 mode = a_mode;
2651 oid = a_oid;
2652 conf = _("file/directory");
2653 } else {
2654 add_branch = o->branch2;
2655 other_branch = o->branch1;
2656 mode = b_mode;
2657 oid = b_oid;
2658 conf = _("directory/file");
2659 }
2660 if (dir_in_way(path,
2661 !o->call_depth && !S_ISGITLINK(a_mode),
2662 0)) {
2663 char *new_path = unique_path(o, path, add_branch);
2664 clean_merge = 0;
2665 output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. "
2666 "Adding %s as %s"),
2667 conf, path, other_branch, path, new_path);
2668 if (update_file(o, 0, oid, mode, new_path))
2669 clean_merge = -1;
2670 else if (o->call_depth)
2671 remove_file_from_cache(path);
2672 free(new_path);
2673 } else {
2674 output(o, 2, _("Adding %s"), path);
2675 /* do not overwrite file if already present */
2676 if (update_file_flags(o, oid, mode, path, 1, !a_oid))
2677 clean_merge = -1;
2678 }
2679 } else if (a_oid && b_oid) {
2680 /* Case C: Added in both (check for same permissions) and */
2681 /* case D: Modified in both, but differently. */
2682 clean_merge = merge_content(o, path,
2683 o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
2684 NULL);
2685 } else if (!o_oid && !a_oid && !b_oid) {
2686 /*
2687 * this entry was deleted altogether. a_mode == 0 means
2688 * we had that path and want to actively remove it.
2689 */
2690 remove_file(o, 1, path, !a_mode);
2691 } else
2692 die("BUG: fatal merge failure, shouldn't happen.");
2693
2694 return clean_merge;
2695}
2696
2697int merge_trees(struct merge_options *o,
2698 struct tree *head,
2699 struct tree *merge,
2700 struct tree *common,
2701 struct tree **result)
2702{
2703 int code, clean;
2704
2705 if (o->subtree_shift) {
2706 merge = shift_tree_object(head, merge, o->subtree_shift);
2707 common = shift_tree_object(head, common, o->subtree_shift);
2708 }
2709
2710 if (oid_eq(&common->object.oid, &merge->object.oid)) {
2711 struct strbuf sb = STRBUF_INIT;
2712
2713 if (!o->call_depth && index_has_changes(&sb)) {
2714 err(o, _("Dirty index: cannot merge (dirty: %s)"),
2715 sb.buf);
2716 return 0;
2717 }
2718 output(o, 0, _("Already up to date!"));
2719 *result = head;
2720 return 1;
2721 }
2722
2723 code = git_merge_trees(o->call_depth, common, head, merge);
2724
2725 if (code != 0) {
2726 if (show(o, 4) || o->call_depth)
2727 err(o, _("merging of trees %s and %s failed"),
2728 oid_to_hex(&head->object.oid),
2729 oid_to_hex(&merge->object.oid));
2730 return -1;
2731 }
2732
2733 if (unmerged_cache()) {
2734 struct string_list *entries;
2735 struct rename_info re_info;
2736 int i;
2737 /*
2738 * Only need the hashmap while processing entries, so
2739 * initialize it here and free it when we are done running
2740 * through the entries. Keeping it in the merge_options as
2741 * opposed to decaring a local hashmap is for convenience
2742 * so that we don't have to pass it to around.
2743 */
2744 hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512);
2745 get_files_dirs(o, head);
2746 get_files_dirs(o, merge);
2747
2748 entries = get_unmerged();
2749 clean = handle_renames(o, common, head, merge, entries,
2750 &re_info);
2751 record_df_conflict_files(o, entries);
2752 if (clean < 0)
2753 goto cleanup;
2754 for (i = entries->nr-1; 0 <= i; i--) {
2755 const char *path = entries->items[i].string;
2756 struct stage_data *e = entries->items[i].util;
2757 if (!e->processed) {
2758 int ret = process_entry(o, path, e);
2759 if (!ret)
2760 clean = 0;
2761 else if (ret < 0) {
2762 clean = ret;
2763 goto cleanup;
2764 }
2765 }
2766 }
2767 for (i = 0; i < entries->nr; i++) {
2768 struct stage_data *e = entries->items[i].util;
2769 if (!e->processed)
2770 die("BUG: unprocessed path??? %s",
2771 entries->items[i].string);
2772 }
2773
2774cleanup:
2775 final_cleanup_renames(&re_info);
2776
2777 string_list_clear(entries, 1);
2778 free(entries);
2779
2780 hashmap_free(&o->current_file_dir_set, 1);
2781
2782 if (clean < 0)
2783 return clean;
2784 }
2785 else
2786 clean = 1;
2787
2788 if (o->call_depth && !(*result = write_tree_from_memory(o)))
2789 return -1;
2790
2791 return clean;
2792}
2793
2794static struct commit_list *reverse_commit_list(struct commit_list *list)
2795{
2796 struct commit_list *next = NULL, *current, *backup;
2797 for (current = list; current; current = backup) {
2798 backup = current->next;
2799 current->next = next;
2800 next = current;
2801 }
2802 return next;
2803}
2804
2805/*
2806 * Merge the commits h1 and h2, return the resulting virtual
2807 * commit object and a flag indicating the cleanness of the merge.
2808 */
2809int merge_recursive(struct merge_options *o,
2810 struct commit *h1,
2811 struct commit *h2,
2812 struct commit_list *ca,
2813 struct commit **result)
2814{
2815 struct commit_list *iter;
2816 struct commit *merged_common_ancestors;
2817 struct tree *mrtree = mrtree;
2818 int clean;
2819
2820 if (show(o, 4)) {
2821 output(o, 4, _("Merging:"));
2822 output_commit_title(o, h1);
2823 output_commit_title(o, h2);
2824 }
2825
2826 if (!ca) {
2827 ca = get_merge_bases(h1, h2);
2828 ca = reverse_commit_list(ca);
2829 }
2830
2831 if (show(o, 5)) {
2832 unsigned cnt = commit_list_count(ca);
2833
2834 output(o, 5, Q_("found %u common ancestor:",
2835 "found %u common ancestors:", cnt), cnt);
2836 for (iter = ca; iter; iter = iter->next)
2837 output_commit_title(o, iter->item);
2838 }
2839
2840 merged_common_ancestors = pop_commit(&ca);
2841 if (merged_common_ancestors == NULL) {
2842 /* if there is no common ancestor, use an empty tree */
2843 struct tree *tree;
2844
2845 tree = lookup_tree(the_hash_algo->empty_tree);
2846 merged_common_ancestors = make_virtual_commit(tree, "ancestor");
2847 }
2848
2849 for (iter = ca; iter; iter = iter->next) {
2850 const char *saved_b1, *saved_b2;
2851 o->call_depth++;
2852 /*
2853 * When the merge fails, the result contains files
2854 * with conflict markers. The cleanness flag is
2855 * ignored (unless indicating an error), it was never
2856 * actually used, as result of merge_trees has always
2857 * overwritten it: the committed "conflicts" were
2858 * already resolved.
2859 */
2860 discard_cache();
2861 saved_b1 = o->branch1;
2862 saved_b2 = o->branch2;
2863 o->branch1 = "Temporary merge branch 1";
2864 o->branch2 = "Temporary merge branch 2";
2865 if (merge_recursive(o, merged_common_ancestors, iter->item,
2866 NULL, &merged_common_ancestors) < 0)
2867 return -1;
2868 o->branch1 = saved_b1;
2869 o->branch2 = saved_b2;
2870 o->call_depth--;
2871
2872 if (!merged_common_ancestors)
2873 return err(o, _("merge returned no commit"));
2874 }
2875
2876 discard_cache();
2877 if (!o->call_depth)
2878 read_cache();
2879
2880 o->ancestor = "merged common ancestors";
2881 clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
2882 &mrtree);
2883 if (clean < 0) {
2884 flush_output(o);
2885 return clean;
2886 }
2887
2888 if (o->call_depth) {
2889 *result = make_virtual_commit(mrtree, "merged tree");
2890 commit_list_insert(h1, &(*result)->parents);
2891 commit_list_insert(h2, &(*result)->parents->next);
2892 }
2893 flush_output(o);
2894 if (!o->call_depth && o->buffer_output < 2)
2895 strbuf_release(&o->obuf);
2896 if (show(o, 2))
2897 diff_warn_rename_limit("merge.renamelimit",
2898 o->needed_rename_limit, 0);
2899 return clean;
2900}
2901
2902static struct commit *get_ref(const struct object_id *oid, const char *name)
2903{
2904 struct object *object;
2905
2906 object = deref_tag(parse_object(oid), name, strlen(name));
2907 if (!object)
2908 return NULL;
2909 if (object->type == OBJ_TREE)
2910 return make_virtual_commit((struct tree*)object, name);
2911 if (object->type != OBJ_COMMIT)
2912 return NULL;
2913 if (parse_commit((struct commit *)object))
2914 return NULL;
2915 return (struct commit *)object;
2916}
2917
2918int merge_recursive_generic(struct merge_options *o,
2919 const struct object_id *head,
2920 const struct object_id *merge,
2921 int num_base_list,
2922 const struct object_id **base_list,
2923 struct commit **result)
2924{
2925 int clean;
2926 struct lock_file lock = LOCK_INIT;
2927 struct commit *head_commit = get_ref(head, o->branch1);
2928 struct commit *next_commit = get_ref(merge, o->branch2);
2929 struct commit_list *ca = NULL;
2930
2931 if (base_list) {
2932 int i;
2933 for (i = 0; i < num_base_list; ++i) {
2934 struct commit *base;
2935 if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i]))))
2936 return err(o, _("Could not parse object '%s'"),
2937 oid_to_hex(base_list[i]));
2938 commit_list_insert(base, &ca);
2939 }
2940 }
2941
2942 hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
2943 clean = merge_recursive(o, head_commit, next_commit, ca,
2944 result);
2945 if (clean < 0)
2946 return clean;
2947
2948 if (active_cache_changed &&
2949 write_locked_index(&the_index, &lock, COMMIT_LOCK))
2950 return err(o, _("Unable to write index."));
2951
2952 return clean ? 0 : 1;
2953}
2954
2955static void merge_recursive_config(struct merge_options *o)
2956{
2957 git_config_get_int("merge.verbosity", &o->verbosity);
2958 git_config_get_int("diff.renamelimit", &o->diff_rename_limit);
2959 git_config_get_int("merge.renamelimit", &o->merge_rename_limit);
2960 git_config(git_xmerge_config, NULL);
2961}
2962
2963void init_merge_options(struct merge_options *o)
2964{
2965 const char *merge_verbosity;
2966 memset(o, 0, sizeof(struct merge_options));
2967 o->verbosity = 2;
2968 o->buffer_output = 1;
2969 o->diff_rename_limit = -1;
2970 o->merge_rename_limit = -1;
2971 o->renormalize = 0;
2972 o->detect_rename = 1;
2973 merge_recursive_config(o);
2974 merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
2975 if (merge_verbosity)
2976 o->verbosity = strtol(merge_verbosity, NULL, 10);
2977 if (o->verbosity >= 5)
2978 o->buffer_output = 0;
2979 strbuf_init(&o->obuf, 0);
2980 string_list_init(&o->df_conflict_file_set, 1);
2981}
2982
2983int parse_merge_opt(struct merge_options *o, const char *s)
2984{
2985 const char *arg;
2986
2987 if (!s || !*s)
2988 return -1;
2989 if (!strcmp(s, "ours"))
2990 o->recursive_variant = MERGE_RECURSIVE_OURS;
2991 else if (!strcmp(s, "theirs"))
2992 o->recursive_variant = MERGE_RECURSIVE_THEIRS;
2993 else if (!strcmp(s, "subtree"))
2994 o->subtree_shift = "";
2995 else if (skip_prefix(s, "subtree=", &arg))
2996 o->subtree_shift = arg;
2997 else if (!strcmp(s, "patience"))
2998 o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF);
2999 else if (!strcmp(s, "histogram"))
3000 o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF);
3001 else if (skip_prefix(s, "diff-algorithm=", &arg)) {
3002 long value = parse_algorithm_value(arg);
3003 if (value < 0)
3004 return -1;
3005 /* clear out previous settings */
3006 DIFF_XDL_CLR(o, NEED_MINIMAL);
3007 o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK;
3008 o->xdl_opts |= value;
3009 }
3010 else if (!strcmp(s, "ignore-space-change"))
3011 DIFF_XDL_SET(o, IGNORE_WHITESPACE_CHANGE);
3012 else if (!strcmp(s, "ignore-all-space"))
3013 DIFF_XDL_SET(o, IGNORE_WHITESPACE);
3014 else if (!strcmp(s, "ignore-space-at-eol"))
3015 DIFF_XDL_SET(o, IGNORE_WHITESPACE_AT_EOL);
3016 else if (!strcmp(s, "ignore-cr-at-eol"))
3017 DIFF_XDL_SET(o, IGNORE_CR_AT_EOL);
3018 else if (!strcmp(s, "renormalize"))
3019 o->renormalize = 1;
3020 else if (!strcmp(s, "no-renormalize"))
3021 o->renormalize = 0;
3022 else if (!strcmp(s, "no-renames"))
3023 o->detect_rename = 0;
3024 else if (!strcmp(s, "find-renames")) {
3025 o->detect_rename = 1;
3026 o->rename_score = 0;
3027 }
3028 else if (skip_prefix(s, "find-renames=", &arg) ||
3029 skip_prefix(s, "rename-threshold=", &arg)) {
3030 if ((o->rename_score = parse_rename_score(&arg)) == -1 || *arg != 0)
3031 return -1;
3032 o->detect_rename = 1;
3033 }
3034 else
3035 return -1;
3036 return 0;
3037}