unpack_trees: group error messages by type
[git/git.git] / unpack-trees.c
CommitLineData
bc052d7f 1#define NO_THE_INDEX_COMPATIBILITY_MACROS
16da134b 2#include "cache.h"
f8a9d428 3#include "dir.h"
16da134b
JS
4#include "tree.h"
5#include "tree-walk.h"
076b0adc 6#include "cache-tree.h"
16da134b 7#include "unpack-trees.h"
96a02f8f 8#include "progress.h"
0cf73755 9#include "refs.h"
06f33c17 10#include "attr.h"
16da134b 11
8ccba008
JH
12/*
13 * Error messages expected by scripts out of plumbing commands such as
14 * read-tree. Non-scripted Porcelain is not required to use these messages
15 * and in fact are encouraged to reword them to better suit their particular
23cbf11b
DG
16 * situation better. See how "git checkout" and "git merge" replaces
17 * them using set_porcelain_error_msgs(), for example.
8ccba008 18 */
08353ebb
MM
19const char *unpack_plumbing_errors[NB_UNPACK_TREES_ERROR_TYPES] = {
20 /* ERROR_WOULD_OVERWRITE */
8ccba008
JH
21 "Entry '%s' would be overwritten by merge. Cannot merge.",
22
08353ebb 23 /* ERROR_NOT_UPTODATE_FILE */
8ccba008
JH
24 "Entry '%s' not uptodate. Cannot merge.",
25
08353ebb 26 /* ERROR_NOT_UPTODATE_DIR */
8ccba008
JH
27 "Updating '%s' would lose untracked files in it",
28
08402b04
MM
29 /* ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN */
30 "Untracked working tree file '%s' would be overwritten by merge.",
31
32 /* ERROR_WOULD_LOSE_UNTRACKED_REMOVED */
33 "Untracked working tree file '%s' would be removed by merge.",
8ccba008 34
08353ebb 35 /* ERROR_BIND_OVERLAP */
8ccba008 36 "Entry '%s' overlaps with '%s'. Cannot bind.",
e800ec9d 37
08353ebb 38 /* ERROR_SPARSE_NOT_UPTODATE_FILE */
e800ec9d
NTND
39 "Entry '%s' not uptodate. Cannot update sparse checkout.",
40
08402b04
MM
41 /* ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN */
42 "Working tree file '%s' would be overwritten by sparse checkout update.",
43
44 /* ERROR_WOULD_LOSE_ORPHANED_REMOVED */
45 "Working tree file '%s' would be removed by sparse checkout update.",
8ccba008
JH
46};
47
08353ebb
MM
48#define ERRORMSG(o,type) \
49 ( ((o) && (o)->msgs[(type)]) \
50 ? ((o)->msgs[(type)]) \
51 : (unpack_plumbing_errors[(type)]) )
8ccba008 52
34110cd4
LT
53static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
54 unsigned int set, unsigned int clear)
b48d5a05 55{
34110cd4
LT
56 unsigned int size = ce_size(ce);
57 struct cache_entry *new = xmalloc(size);
58
59 clear |= CE_HASHED | CE_UNHASHED;
60
61 memcpy(new, ce, size);
62 new->next = NULL;
63 new->ce_flags = (new->ce_flags & ~clear) | set;
aab3b9a1 64 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
b48d5a05
LT
65}
66
e6c111b4
MM
67/*
68 * add error messages on path <path>
69 * corresponding to the type <e> with the message <msg>
70 * indicating if it should be display in porcelain or not
71 */
72static int add_rejected_path(struct unpack_trees_options *o,
73 enum unpack_trees_error_types e,
74 const char *path)
75{
76 struct rejected_paths_list *newentry;
77 int porcelain = o && (o)->msgs[e];
78 /*
79 * simply display the given error message if in plumbing mode
80 */
81 if (!porcelain)
82 o->show_all_errors = 0;
83 if (!o->show_all_errors)
84 return error(ERRORMSG(o, e), path);
85
86 /*
87 * Otherwise, insert in a list for future display by
88 * display_error_msgs()
89 */
90 newentry = xmalloc(sizeof(struct rejected_paths_list));
91 newentry->path = (char *)path;
92 newentry->next = o->unpack_rejects[e];
93 o->unpack_rejects[e] = newentry;
94 return -1;
95}
96
97/*
98 * free all the structures allocated for the error <e>
99 */
100static void free_rejected_paths(struct unpack_trees_options *o,
101 enum unpack_trees_error_types e)
102{
103 while (o->unpack_rejects[e]) {
104 struct rejected_paths_list *del = o->unpack_rejects[e];
105 o->unpack_rejects[e] = o->unpack_rejects[e]->next;
106 free(del);
107 }
108 free(o->unpack_rejects[e]);
109}
110
111/*
112 * display all the error messages stored in a nice way
113 */
114static void display_error_msgs(struct unpack_trees_options *o)
115{
116 int e;
117 int something_displayed = 0;
118 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
119 if (o->unpack_rejects[e]) {
120 struct rejected_paths_list *rp;
121 struct strbuf path = STRBUF_INIT;
122 something_displayed = 1;
123 for (rp = o->unpack_rejects[e]; rp; rp = rp->next)
124 strbuf_addf(&path, "\t%s\n", rp->path);
125 error(ERRORMSG(o, e), path.buf);
126 strbuf_release(&path);
127 free_rejected_paths(o, e);
128 }
129 }
130 if (something_displayed)
131 printf("Aborting\n");
132}
133
78478927
KB
134/*
135 * Unlink the last component and schedule the leading directories for
136 * removal, such that empty directories get removed.
16da134b 137 */
c40641b7 138static void unlink_entry(struct cache_entry *ce)
16da134b 139{
57199892 140 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
16a4c617 141 return;
80d706af
PC
142 if (remove_or_warn(ce->ce_mode, ce->name))
143 return;
78478927 144 schedule_dir_for_removal(ce->name, ce_namelen(ce));
16da134b
JS
145}
146
16da134b 147static struct checkout state;
c4758d3c 148static int check_updates(struct unpack_trees_options *o)
16da134b 149{
96a02f8f 150 unsigned cnt = 0, total = 0;
dc6a0757 151 struct progress *progress = NULL;
34110cd4 152 struct index_state *index = &o->result;
33ecf7eb 153 int i;
c4758d3c 154 int errs = 0;
16da134b
JS
155
156 if (o->update && o->verbose_update) {
34110cd4
LT
157 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
158 struct cache_entry *ce = index->cache[cnt];
e663db2f 159 if (ce->ce_flags & (CE_UPDATE | CE_REMOVE | CE_WT_REMOVE))
16da134b
JS
160 total++;
161 }
162
dc6a0757 163 progress = start_progress_delay("Checking out files",
e8548645 164 total, 50, 1);
16da134b
JS
165 cnt = 0;
166 }
167
66985e66
JH
168 if (o->update)
169 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
34110cd4
LT
170 for (i = 0; i < index->cache_nr; i++) {
171 struct cache_entry *ce = index->cache[i];
16da134b 172
e663db2f
NTND
173 if (ce->ce_flags & CE_WT_REMOVE) {
174 display_progress(progress, ++cnt);
175 if (o->update)
176 unlink_entry(ce);
177 continue;
178 }
179
7a51ed66 180 if (ce->ce_flags & CE_REMOVE) {
1fa6ead4 181 display_progress(progress, ++cnt);
16da134b 182 if (o->update)
c40641b7 183 unlink_entry(ce);
16da134b 184 }
1fa6ead4 185 }
36419c8e 186 remove_marked_cache_entries(&o->result);
78478927 187 remove_scheduled_dirs();
1fa6ead4
LT
188
189 for (i = 0; i < index->cache_nr; i++) {
190 struct cache_entry *ce = index->cache[i];
191
7a51ed66 192 if (ce->ce_flags & CE_UPDATE) {
1fa6ead4 193 display_progress(progress, ++cnt);
7a51ed66 194 ce->ce_flags &= ~CE_UPDATE;
16a4c617 195 if (o->update) {
c4758d3c 196 errs |= checkout_entry(ce, &state, NULL);
16a4c617 197 }
16da134b
JS
198 }
199 }
4d4fcc54 200 stop_progress(&progress);
66985e66
JH
201 if (o->update)
202 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
c4758d3c 203 return errs != 0;
16da134b
JS
204}
205
e800ec9d 206static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
08402b04 207static int verify_absent_sparse(struct cache_entry *ce, enum unpack_trees_error_types, struct unpack_trees_options *o);
e800ec9d
NTND
208
209static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
210{
211 const char *basename;
212
213 if (ce_stage(ce))
214 return 0;
215
216 basename = strrchr(ce->name, '/');
217 basename = basename ? basename+1 : ce->name;
218 return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
219}
220
221static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
222{
223 int was_skip_worktree = ce_skip_worktree(ce);
224
225 if (will_have_skip_worktree(ce, o))
226 ce->ce_flags |= CE_SKIP_WORKTREE;
227 else
228 ce->ce_flags &= ~CE_SKIP_WORKTREE;
229
230 /*
231 * We only care about files getting into the checkout area
232 * If merge strategies want to remove some, go ahead, this
233 * flag will be removed eventually in unpack_trees() if it's
234 * outside checkout area.
235 */
236 if (ce->ce_flags & CE_REMOVE)
237 return 0;
238
239 if (!was_skip_worktree && ce_skip_worktree(ce)) {
240 /*
241 * If CE_UPDATE is set, verify_uptodate() must be called already
242 * also stat info may have lost after merged_entry() so calling
243 * verify_uptodate() again may fail
244 */
245 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
246 return -1;
247 ce->ce_flags |= CE_WT_REMOVE;
248 }
249 if (was_skip_worktree && !ce_skip_worktree(ce)) {
08402b04 250 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
e800ec9d
NTND
251 return -1;
252 ce->ce_flags |= CE_UPDATE;
253 }
254 return 0;
255}
256
34110cd4 257static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
01904572 258{
34110cd4
LT
259 int ret = o->fn(src, o);
260 if (ret > 0)
01904572 261 ret = 0;
01904572
LT
262 return ret;
263}
264
da165f47
JH
265static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
266{
267 ce->ce_flags |= CE_UNPACKED;
268
269 if (o->cache_bottom < o->src_index->cache_nr &&
270 o->src_index->cache[o->cache_bottom] == ce) {
271 int bottom = o->cache_bottom;
272 while (bottom < o->src_index->cache_nr &&
273 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
274 bottom++;
275 o->cache_bottom = bottom;
276 }
277}
278
279static void mark_all_ce_unused(struct index_state *index)
280{
281 int i;
282 for (i = 0; i < index->cache_nr; i++)
283 index->cache[i]->ce_flags &= ~CE_UNPACKED;
284}
285
286static int locate_in_src_index(struct cache_entry *ce,
287 struct unpack_trees_options *o)
288{
289 struct index_state *index = o->src_index;
290 int len = ce_namelen(ce);
291 int pos = index_name_pos(index, ce->name, len);
292 if (pos < 0)
293 pos = -1 - pos;
294 return pos;
295}
296
297/*
298 * We call unpack_index_entry() with an unmerged cache entry
299 * only in diff-index, and it wants a single callback. Skip
300 * the other unmerged entry with the same name.
301 */
302static void mark_ce_used_same_name(struct cache_entry *ce,
303 struct unpack_trees_options *o)
304{
305 struct index_state *index = o->src_index;
306 int len = ce_namelen(ce);
307 int pos;
308
309 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
310 struct cache_entry *next = index->cache[pos];
311 if (len != ce_namelen(next) ||
312 memcmp(ce->name, next->name, len))
313 break;
314 mark_ce_used(next, o);
315 }
316}
317
318static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
319{
320 const struct index_state *index = o->src_index;
321 int pos = o->cache_bottom;
322
323 while (pos < index->cache_nr) {
324 struct cache_entry *ce = index->cache[pos];
325 if (!(ce->ce_flags & CE_UNPACKED))
326 return ce;
327 pos++;
328 }
329 return NULL;
330}
331
332static void add_same_unmerged(struct cache_entry *ce,
333 struct unpack_trees_options *o)
334{
335 struct index_state *index = o->src_index;
336 int len = ce_namelen(ce);
337 int pos = index_name_pos(index, ce->name, len);
338
339 if (0 <= pos)
340 die("programming error in a caller of mark_ce_used_same_name");
341 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
342 struct cache_entry *next = index->cache[pos];
343 if (len != ce_namelen(next) ||
344 memcmp(ce->name, next->name, len))
345 break;
346 add_entry(o, next, 0, 0);
347 mark_ce_used(next, o);
348 }
349}
350
351static int unpack_index_entry(struct cache_entry *ce,
352 struct unpack_trees_options *o)
01904572 353{
66dbfd55 354 struct cache_entry *src[5] = { NULL };
da165f47 355 int ret;
34110cd4 356
66dbfd55
GV
357 src[0] = ce;
358
da165f47 359 mark_ce_used(ce, o);
01904572
LT
360 if (ce_stage(ce)) {
361 if (o->skip_unmerged) {
34110cd4
LT
362 add_entry(o, ce, 0, 0);
363 return 0;
01904572 364 }
01904572 365 }
da165f47
JH
366 ret = call_unpack_fn(src, o);
367 if (ce_stage(ce))
368 mark_ce_used_same_name(ce, o);
369 return ret;
01904572
LT
370}
371
730f7284
JH
372static int find_cache_pos(struct traverse_info *, const struct name_entry *);
373
374static void restore_cache_bottom(struct traverse_info *info, int bottom)
375{
376 struct unpack_trees_options *o = info->data;
377
378 if (o->diff_index_cached)
379 return;
380 o->cache_bottom = bottom;
381}
382
383static int switch_cache_bottom(struct traverse_info *info)
384{
385 struct unpack_trees_options *o = info->data;
386 int ret, pos;
387
388 if (o->diff_index_cached)
389 return 0;
390 ret = o->cache_bottom;
391 pos = find_cache_pos(info->prev, &info->name);
392
393 if (pos < -1)
394 o->cache_bottom = -2 - pos;
395 else if (pos < 0)
396 o->cache_bottom = o->src_index->cache_nr;
397 return ret;
01904572
LT
398}
399
2af202be 400static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
16da134b 401{
730f7284 402 int i, ret, bottom;
ca885a4f 403 struct tree_desc t[MAX_UNPACK_TREES];
01904572
LT
404 struct traverse_info newinfo;
405 struct name_entry *p;
406
407 p = names;
408 while (!p->mode)
409 p++;
410
411 newinfo = *info;
412 newinfo.prev = info;
413 newinfo.name = *p;
414 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
415 newinfo.conflicts |= df_conflicts;
416
417 for (i = 0; i < n; i++, dirmask >>= 1) {
418 const unsigned char *sha1 = NULL;
419 if (dirmask & 1)
420 sha1 = names[i].sha1;
421 fill_tree_descriptor(t+i, sha1);
422 }
730f7284
JH
423
424 bottom = switch_cache_bottom(&newinfo);
425 ret = traverse_trees(n, t, &newinfo);
426 restore_cache_bottom(&newinfo, bottom);
427 return ret;
01904572
LT
428}
429
430/*
431 * Compare the traverse-path to the cache entry without actually
432 * having to generate the textual representation of the traverse
433 * path.
434 *
435 * NOTE! This *only* compares up to the size of the traverse path
436 * itself - the caller needs to do the final check for the cache
437 * entry having more data at the end!
438 */
439static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
440{
441 int len, pathlen, ce_len;
442 const char *ce_name;
443
444 if (info->prev) {
445 int cmp = do_compare_entry(ce, info->prev, &info->name);
446 if (cmp)
447 return cmp;
448 }
449 pathlen = info->pathlen;
450 ce_len = ce_namelen(ce);
451
452 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
453 if (ce_len < pathlen)
454 return -1;
455
456 ce_len -= pathlen;
457 ce_name = ce->name + pathlen;
458
459 len = tree_entry_len(n->path, n->sha1);
460 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
461}
462
463static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
464{
465 int cmp = do_compare_entry(ce, info, n);
466 if (cmp)
467 return cmp;
468
469 /*
470 * Even if the beginning compared identically, the ce should
471 * compare as bigger than a directory leading up to it!
472 */
473 return ce_namelen(ce) > traverse_path_len(info, n);
474}
475
da165f47
JH
476static int ce_in_traverse_path(const struct cache_entry *ce,
477 const struct traverse_info *info)
478{
479 if (!info->prev)
480 return 1;
481 if (do_compare_entry(ce, info->prev, &info->name))
482 return 0;
483 /*
484 * If ce (blob) is the same name as the path (which is a tree
485 * we will be descending into), it won't be inside it.
486 */
487 return (info->pathlen < ce_namelen(ce));
488}
489
01904572
LT
490static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
491{
492 int len = traverse_path_len(info, n);
493 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
494
495 ce->ce_mode = create_ce_mode(n->mode);
496 ce->ce_flags = create_ce_flags(len, stage);
497 hashcpy(ce->sha1, n->sha1);
498 make_traverse_path(ce->name, info, n);
499
500 return ce;
501}
502
c7cddc1a
RS
503static int unpack_nondirectories(int n, unsigned long mask,
504 unsigned long dirmask,
505 struct cache_entry **src,
506 const struct name_entry *names,
507 const struct traverse_info *info)
01904572
LT
508{
509 int i;
510 struct unpack_trees_options *o = info->data;
511 unsigned long conflicts;
512
513 /* Do we have *only* directories? Nothing to do */
514 if (mask == dirmask && !src[0])
515 return 0;
516
517 conflicts = info->conflicts;
518 if (o->merge)
519 conflicts >>= 1;
520 conflicts |= dirmask;
521
522 /*
523 * Ok, we've filled in up to any potential index entry in src[0],
524 * now do the rest.
525 */
526 for (i = 0; i < n; i++) {
527 int stage;
528 unsigned int bit = 1ul << i;
529 if (conflicts & bit) {
530 src[i + o->merge] = o->df_conflict_entry;
531 continue;
532 }
533 if (!(mask & bit))
534 continue;
535 if (!o->merge)
536 stage = 0;
537 else if (i + 1 < o->head_idx)
538 stage = 1;
539 else if (i + 1 > o->head_idx)
540 stage = 3;
541 else
542 stage = 2;
543 src[i + o->merge] = create_ce_entry(info, names + i, stage);
544 }
545
546 if (o->merge)
34110cd4 547 return call_unpack_fn(src, o);
01904572 548
01904572 549 for (i = 0; i < n; i++)
aab3b9a1
JH
550 if (src[i] && src[i] != o->df_conflict_entry)
551 add_entry(o, src[i], 0, 0);
01904572
LT
552 return 0;
553}
554
353c5eeb
JH
555static int unpack_failed(struct unpack_trees_options *o, const char *message)
556{
557 discard_index(&o->result);
558 if (!o->gently) {
559 if (message)
560 return error("%s", message);
561 return -1;
562 }
563 return -1;
564}
565
730f7284
JH
566/* NEEDSWORK: give this a better name and share with tree-walk.c */
567static int name_compare(const char *a, int a_len,
568 const char *b, int b_len)
569{
570 int len = (a_len < b_len) ? a_len : b_len;
571 int cmp = memcmp(a, b, len);
572 if (cmp)
573 return cmp;
574 return (a_len - b_len);
575}
576
577/*
578 * The tree traversal is looking at name p. If we have a matching entry,
579 * return it. If name p is a directory in the index, do not return
580 * anything, as we will want to match it when the traversal descends into
581 * the directory.
582 */
583static int find_cache_pos(struct traverse_info *info,
584 const struct name_entry *p)
585{
586 int pos;
587 struct unpack_trees_options *o = info->data;
588 struct index_state *index = o->src_index;
589 int pfxlen = info->pathlen;
590 int p_len = tree_entry_len(p->path, p->sha1);
591
592 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
593 struct cache_entry *ce = index->cache[pos];
594 const char *ce_name, *ce_slash;
595 int cmp, ce_len;
596
e53e6b44
BD
597 if (ce->ce_flags & CE_UNPACKED) {
598 /*
599 * cache_bottom entry is already unpacked, so
600 * we can never match it; don't check it
601 * again.
602 */
603 if (pos == o->cache_bottom)
604 ++o->cache_bottom;
730f7284 605 continue;
e53e6b44
BD
606 }
607 if (!ce_in_traverse_path(ce, info))
730f7284
JH
608 continue;
609 ce_name = ce->name + pfxlen;
610 ce_slash = strchr(ce_name, '/');
611 if (ce_slash)
612 ce_len = ce_slash - ce_name;
613 else
614 ce_len = ce_namelen(ce) - pfxlen;
615 cmp = name_compare(p->path, p_len, ce_name, ce_len);
616 /*
617 * Exact match; if we have a directory we need to
618 * delay returning it.
619 */
620 if (!cmp)
621 return ce_slash ? -2 - pos : pos;
622 if (0 < cmp)
623 continue; /* keep looking */
624 /*
625 * ce_name sorts after p->path; could it be that we
626 * have files under p->path directory in the index?
627 * E.g. ce_name == "t-i", and p->path == "t"; we may
628 * have "t/a" in the index.
629 */
630 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
631 ce_name[p_len] < '/')
632 continue; /* keep looking */
633 break;
634 }
635 return -1;
636}
637
638static struct cache_entry *find_cache_entry(struct traverse_info *info,
639 const struct name_entry *p)
640{
641 int pos = find_cache_pos(info, p);
642 struct unpack_trees_options *o = info->data;
643
644 if (0 <= pos)
645 return o->src_index->cache[pos];
646 else
647 return NULL;
648}
649
ba655da5
JH
650static void debug_path(struct traverse_info *info)
651{
652 if (info->prev) {
653 debug_path(info->prev);
654 if (*info->prev->name.path)
655 putchar('/');
656 }
657 printf("%s", info->name.path);
658}
659
660static void debug_name_entry(int i, struct name_entry *n)
661{
662 printf("ent#%d %06o %s\n", i,
663 n->path ? n->mode : 0,
664 n->path ? n->path : "(missing)");
665}
666
667static void debug_unpack_callback(int n,
668 unsigned long mask,
669 unsigned long dirmask,
670 struct name_entry *names,
671 struct traverse_info *info)
672{
673 int i;
674 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
675 mask, dirmask, n);
676 debug_path(info);
677 putchar('\n');
678 for (i = 0; i < n; i++)
679 debug_name_entry(i, names + i);
680}
681
01904572
LT
682static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
683{
c7cddc1a 684 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
01904572 685 struct unpack_trees_options *o = info->data;
01904572
LT
686 const struct name_entry *p = names;
687
688 /* Find first entry with a real name (we could use "mask" too) */
689 while (!p->mode)
690 p++;
691
ba655da5
JH
692 if (o->debug_unpack)
693 debug_unpack_callback(n, mask, dirmask, names, info);
694
01904572
LT
695 /* Are we supposed to look at the index too? */
696 if (o->merge) {
da165f47 697 while (1) {
da165f47 698 int cmp;
730f7284
JH
699 struct cache_entry *ce;
700
701 if (o->diff_index_cached)
702 ce = next_cache_entry(o);
703 else
704 ce = find_cache_entry(info, p);
705
da165f47
JH
706 if (!ce)
707 break;
708 cmp = compare_entry(ce, info, p);
01904572
LT
709 if (cmp < 0) {
710 if (unpack_index_entry(ce, o) < 0)
353c5eeb 711 return unpack_failed(o, NULL);
01904572
LT
712 continue;
713 }
714 if (!cmp) {
715 if (ce_stage(ce)) {
716 /*
da165f47
JH
717 * If we skip unmerged index
718 * entries, we'll skip this
719 * entry *and* the tree
720 * entries associated with it!
01904572 721 */
34110cd4 722 if (o->skip_unmerged) {
da165f47 723 add_same_unmerged(ce, o);
01904572 724 return mask;
34110cd4 725 }
01904572
LT
726 }
727 src[0] = ce;
01904572
LT
728 }
729 break;
730 }
731 }
732
34110cd4 733 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
01904572
LT
734 return -1;
735
da165f47
JH
736 if (src[0]) {
737 if (ce_stage(src[0]))
738 mark_ce_used_same_name(src[0], o);
739 else
740 mark_ce_used(src[0], o);
741 }
742
01904572
LT
743 /* Now handle any directories.. */
744 if (dirmask) {
745 unsigned long conflicts = mask & ~dirmask;
746 if (o->merge) {
747 conflicts <<= 1;
748 if (src[0])
749 conflicts |= 1;
750 }
b65982b6
JH
751
752 /* special case: "diff-index --cached" looking at a tree */
753 if (o->diff_index_cached &&
754 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
755 int matches;
756 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
757 names, info);
758 /*
da165f47
JH
759 * Everything under the name matches; skip the
760 * entire hierarchy. diff_index_cached codepath
761 * special cases D/F conflicts in such a way that
762 * it does not do any look-ahead, so this is safe.
b65982b6
JH
763 */
764 if (matches) {
da165f47 765 o->cache_bottom += matches;
b65982b6
JH
766 return mask;
767 }
768 }
769
542c264b
JH
770 if (traverse_trees_recursive(n, dirmask, conflicts,
771 names, info) < 0)
772 return -1;
01904572
LT
773 return mask;
774 }
775
776 return mask;
777}
778
2e2b887d
JH
779/*
780 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
781 * resulting index, -2 on failure to reflect the changes to the work tree.
782 */
01904572
LT
783int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
784{
e800ec9d 785 int i, ret;
0fb1eaa8 786 static struct cache_entry *dfc;
08aefc9e 787 struct exclude_list el;
16da134b 788
ca885a4f
JH
789 if (len > MAX_UNPACK_TREES)
790 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
076b0adc 791 memset(&state, 0, sizeof(state));
16da134b
JS
792 state.base_dir = "";
793 state.force = 1;
794 state.quiet = 1;
795 state.refresh_cache = 1;
796
08aefc9e
NTND
797 memset(&el, 0, sizeof(el));
798 if (!core_apply_sparse_checkout || !o->update)
799 o->skip_sparse_checkout = 1;
800 if (!o->skip_sparse_checkout) {
801 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
802 o->skip_sparse_checkout = 1;
803 else
804 o->el = &el;
805 }
806
34110cd4 807 memset(&o->result, 0, sizeof(o->result));
913e0e99 808 o->result.initialized = 1;
da165f47
JH
809 o->result.timestamp.sec = o->src_index->timestamp.sec;
810 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
16da134b 811 o->merge_size = len;
da165f47 812 mark_all_ce_unused(o->src_index);
0fb1eaa8
JH
813
814 if (!dfc)
13494ed1 815 dfc = xcalloc(1, cache_entry_size(0));
0fb1eaa8 816 o->df_conflict_entry = dfc;
16da134b
JS
817
818 if (len) {
01904572
LT
819 const char *prefix = o->prefix ? o->prefix : "";
820 struct traverse_info info;
821
822 setup_traverse_info(&info, prefix);
823 info.fn = unpack_callback;
824 info.data = o;
e6c111b4 825 info.show_all_errors = o->show_all_errors;
01904572 826
da165f47
JH
827 if (o->prefix) {
828 /*
829 * Unpack existing index entries that sort before the
830 * prefix the tree is spliced into. Note that o->merge
831 * is always true in this case.
832 */
833 while (1) {
834 struct cache_entry *ce = next_cache_entry(o);
835 if (!ce)
836 break;
837 if (ce_in_traverse_path(ce, &info))
838 break;
839 if (unpack_index_entry(ce, o) < 0)
840 goto return_failed;
841 }
08aefc9e 842 }
da165f47 843
01904572 844 if (traverse_trees(len, t, &info) < 0)
da165f47 845 goto return_failed;
16da134b
JS
846 }
847
01904572
LT
848 /* Any left-over entries in the index? */
849 if (o->merge) {
da165f47
JH
850 while (1) {
851 struct cache_entry *ce = next_cache_entry(o);
852 if (!ce)
853 break;
01904572 854 if (unpack_index_entry(ce, o) < 0)
da165f47 855 goto return_failed;
17e46426 856 }
17e46426 857 }
da165f47 858 mark_all_ce_unused(o->src_index);
16da134b 859
08aefc9e
NTND
860 if (o->trivial_merges_only && o->nontrivial_merge) {
861 ret = unpack_failed(o, "Merge requires file-level merging");
862 goto done;
863 }
01904572 864
e800ec9d 865 if (!o->skip_sparse_checkout) {
9e1afb16 866 int empty_worktree = 1;
e800ec9d
NTND
867 for (i = 0;i < o->result.cache_nr;i++) {
868 struct cache_entry *ce = o->result.cache[i];
869
870 if (apply_sparse_checkout(ce, o)) {
871 ret = -1;
872 goto done;
873 }
f1f523ea
NTND
874 /*
875 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
876 * area as a result of ce_skip_worktree() shortcuts in
877 * verify_absent() and verify_uptodate(). Clear them.
878 */
879 if (ce_skip_worktree(ce))
880 ce->ce_flags &= ~(CE_UPDATE | CE_REMOVE);
9e1afb16
NTND
881 else
882 empty_worktree = 0;
f1f523ea 883
e800ec9d 884 }
9e1afb16
NTND
885 if (o->result.cache_nr && empty_worktree) {
886 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
887 goto done;
888 }
e800ec9d 889 }
01904572 890
34110cd4 891 o->src_index = NULL;
2e2b887d 892 ret = check_updates(o) ? (-2) : 0;
34110cd4
LT
893 if (o->dst_index)
894 *o->dst_index = o->result;
08aefc9e
NTND
895
896done:
897 for (i = 0;i < el.nr;i++)
898 free(el.excludes[i]);
899 if (el.excludes)
900 free(el.excludes);
901
2e2b887d 902 return ret;
da165f47
JH
903
904return_failed:
e6c111b4
MM
905 if (o->show_all_errors)
906 display_error_msgs(o);
da165f47 907 mark_all_ce_unused(o->src_index);
026680f8
JH
908 ret = unpack_failed(o, NULL);
909 goto done;
16da134b 910}
076b0adc
JS
911
912/* Here come the merge functions */
913
8ccba008 914static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc 915{
e6c111b4 916 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
076b0adc
JS
917}
918
919static int same(struct cache_entry *a, struct cache_entry *b)
920{
921 if (!!a != !!b)
922 return 0;
923 if (!a && !b)
924 return 1;
e11d7b59
JH
925 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
926 return 0;
076b0adc 927 return a->ce_mode == b->ce_mode &&
a89fccd2 928 !hashcmp(a->sha1, b->sha1);
076b0adc
JS
929}
930
931
932/*
933 * When a CE gets turned into an unmerged entry, we
934 * want it to be up-to-date
935 */
35a5aa79
NTND
936static int verify_uptodate_1(struct cache_entry *ce,
937 struct unpack_trees_options *o,
08402b04 938 enum unpack_trees_error_types error_type)
076b0adc
JS
939{
940 struct stat st;
941
aecda37c 942 if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
203a2fe1 943 return 0;
076b0adc
JS
944
945 if (!lstat(ce->name, &st)) {
56cac48c 946 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
076b0adc 947 if (!changed)
203a2fe1 948 return 0;
936492d3
JH
949 /*
950 * NEEDSWORK: the current default policy is to allow
951 * submodule to be out of sync wrt the supermodule
952 * index. This needs to be tightened later for
953 * submodules that are marked to be automatically
954 * checked out.
955 */
7a51ed66 956 if (S_ISGITLINK(ce->ce_mode))
203a2fe1 957 return 0;
076b0adc
JS
958 errno = 0;
959 }
076b0adc 960 if (errno == ENOENT)
203a2fe1 961 return 0;
17e46426 962 return o->gently ? -1 :
e6c111b4 963 add_rejected_path(o, error_type, ce->name);
35a5aa79
NTND
964}
965
966static int verify_uptodate(struct cache_entry *ce,
967 struct unpack_trees_options *o)
968{
f1f523ea
NTND
969 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
970 return 0;
08402b04 971 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
076b0adc
JS
972}
973
e800ec9d
NTND
974static int verify_uptodate_sparse(struct cache_entry *ce,
975 struct unpack_trees_options *o)
976{
08402b04 977 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
076b0adc
JS
978}
979
bc052d7f 980static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc
JS
981{
982 if (ce)
34110cd4 983 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
076b0adc
JS
984}
985
0cf73755
SV
986/*
987 * Check that checking out ce->sha1 in subdir ce->name is not
988 * going to overwrite any working files.
989 *
990 * Currently, git does not checkout subprojects during a superproject
991 * checkout, so it is not going to overwrite anything.
992 */
08402b04
MM
993static int verify_clean_submodule(struct cache_entry *ce,
994 enum unpack_trees_error_types error_type,
0cf73755
SV
995 struct unpack_trees_options *o)
996{
997 return 0;
998}
999
08402b04
MM
1000static int verify_clean_subdirectory(struct cache_entry *ce,
1001 enum unpack_trees_error_types error_type,
c8193534
JH
1002 struct unpack_trees_options *o)
1003{
1004 /*
0cf73755 1005 * we are about to extract "ce->name"; we would not want to lose
c8193534
JH
1006 * anything in the existing directory there.
1007 */
1008 int namelen;
7b9e3ce0 1009 int i;
c8193534
JH
1010 struct dir_struct d;
1011 char *pathbuf;
1012 int cnt = 0;
0cf73755
SV
1013 unsigned char sha1[20];
1014
7a51ed66 1015 if (S_ISGITLINK(ce->ce_mode) &&
0cf73755
SV
1016 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1017 /* If we are not going to update the submodule, then
1018 * we don't care.
1019 */
1020 if (!hashcmp(sha1, ce->sha1))
1021 return 0;
08402b04 1022 return verify_clean_submodule(ce, error_type, o);
0cf73755 1023 }
c8193534
JH
1024
1025 /*
1026 * First let's make sure we do not have a local modification
1027 * in that directory.
1028 */
0cf73755 1029 namelen = strlen(ce->name);
da165f47
JH
1030 for (i = locate_in_src_index(ce, o);
1031 i < o->src_index->cache_nr;
1032 i++) {
837e5fe9
CB
1033 struct cache_entry *ce2 = o->src_index->cache[i];
1034 int len = ce_namelen(ce2);
c8193534 1035 if (len < namelen ||
837e5fe9
CB
1036 strncmp(ce->name, ce2->name, namelen) ||
1037 ce2->name[namelen] != '/')
c8193534
JH
1038 break;
1039 /*
da165f47
JH
1040 * ce2->name is an entry in the subdirectory to be
1041 * removed.
c8193534 1042 */
837e5fe9
CB
1043 if (!ce_stage(ce2)) {
1044 if (verify_uptodate(ce2, o))
203a2fe1 1045 return -1;
837e5fe9 1046 add_entry(o, ce2, CE_REMOVE, 0);
da165f47 1047 mark_ce_used(ce2, o);
c8193534
JH
1048 }
1049 cnt++;
1050 }
1051
1052 /*
1053 * Then we need to make sure that we do not lose a locally
1054 * present file that is not ignored.
1055 */
1056 pathbuf = xmalloc(namelen + 2);
0cf73755 1057 memcpy(pathbuf, ce->name, namelen);
c8193534
JH
1058 strcpy(pathbuf+namelen, "/");
1059
1060 memset(&d, 0, sizeof(d));
1061 if (o->dir)
1062 d.exclude_per_dir = o->dir->exclude_per_dir;
dba2e203 1063 i = read_directory(&d, pathbuf, namelen+1, NULL);
c8193534 1064 if (i)
17e46426 1065 return o->gently ? -1 :
e6c111b4 1066 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
c8193534
JH
1067 free(pathbuf);
1068 return cnt;
1069}
1070
32260ad5
LT
1071/*
1072 * This gets called when there was no index entry for the tree entry 'dst',
1073 * but we found a file in the working tree that 'lstat()' said was fine,
1074 * and we're on a case-insensitive filesystem.
1075 *
1076 * See if we can find a case-insensitive match in the index that also
1077 * matches the stat information, and assume it's that other file!
1078 */
1079static int icase_exists(struct unpack_trees_options *o, struct cache_entry *dst, struct stat *st)
1080{
1081 struct cache_entry *src;
1082
1083 src = index_name_exists(o->src_index, dst->name, ce_namelen(dst), 1);
56cac48c 1084 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
32260ad5
LT
1085}
1086
076b0adc
JS
1087/*
1088 * We do not want to remove or overwrite a working tree file that
f8a9d428 1089 * is not tracked, unless it is ignored.
076b0adc 1090 */
08402b04
MM
1091static int verify_absent_1(struct cache_entry *ce,
1092 enum unpack_trees_error_types error_type,
1093 struct unpack_trees_options *o)
076b0adc
JS
1094{
1095 struct stat st;
1096
1097 if (o->index_only || o->reset || !o->update)
203a2fe1 1098 return 0;
c8193534 1099
57199892 1100 if (has_symlink_or_noent_leading_path(ce->name, ce_namelen(ce)))
203a2fe1 1101 return 0;
ec0603e1 1102
0cf73755 1103 if (!lstat(ce->name, &st)) {
6831a88a 1104 int dtype = ce_to_dtype(ce);
df292c79 1105 struct cache_entry *result;
c8193534 1106
32260ad5
LT
1107 /*
1108 * It may be that the 'lstat()' succeeded even though
1109 * target 'ce' was absent, because there is an old
1110 * entry that is different only in case..
1111 *
1112 * Ignore that lstat() if it matches.
1113 */
1114 if (ignore_case && icase_exists(o, ce, &st))
1115 return 0;
1116
6831a88a 1117 if (o->dir && excluded(o->dir, ce->name, &dtype))
c8193534 1118 /*
0cf73755 1119 * ce->name is explicitly excluded, so it is Ok to
c8193534
JH
1120 * overwrite it.
1121 */
203a2fe1 1122 return 0;
c8193534
JH
1123 if (S_ISDIR(st.st_mode)) {
1124 /*
1125 * We are checking out path "foo" and
1126 * found "foo/." in the working tree.
1127 * This is tricky -- if we have modified
1128 * files that are in "foo/" we would lose
6caa7b55 1129 * them.
c8193534 1130 */
08402b04 1131 if (verify_clean_subdirectory(ce, error_type, o) < 0)
da165f47 1132 return -1;
203a2fe1 1133 return 0;
c8193534
JH
1134 }
1135
1136 /*
1137 * The previous round may already have decided to
1138 * delete this path, which is in a subdirectory that
1139 * is being replaced with a blob.
1140 */
cd2fef59 1141 result = index_name_exists(&o->result, ce->name, ce_namelen(ce), 0);
df292c79
LT
1142 if (result) {
1143 if (result->ce_flags & CE_REMOVE)
203a2fe1 1144 return 0;
c8193534
JH
1145 }
1146
17e46426 1147 return o->gently ? -1 :
e6c111b4 1148 add_rejected_path(o, error_type, ce->name);
c8193534 1149 }
203a2fe1 1150 return 0;
076b0adc 1151}
08402b04
MM
1152static int verify_absent(struct cache_entry *ce,
1153 enum unpack_trees_error_types error_type,
35a5aa79
NTND
1154 struct unpack_trees_options *o)
1155{
f1f523ea
NTND
1156 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
1157 return 0;
08402b04 1158 return verify_absent_1(ce, error_type, o);
35a5aa79 1159}
076b0adc 1160
08402b04
MM
1161static int verify_absent_sparse(struct cache_entry *ce,
1162 enum unpack_trees_error_types error_type,
e800ec9d
NTND
1163 struct unpack_trees_options *o)
1164{
08402b04
MM
1165 enum unpack_trees_error_types orphaned_error = error_type;
1166 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1167 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1168
1169 return verify_absent_1(ce, orphaned_error, o);
e800ec9d 1170}
076b0adc
JS
1171
1172static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1173 struct unpack_trees_options *o)
1174{
7f8ab8dc
LT
1175 int update = CE_UPDATE;
1176
e11d7b59 1177 if (!old) {
08402b04 1178 if (verify_absent(merge, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
e11d7b59
JH
1179 return -1;
1180 invalidate_ce_path(merge, o);
1181 } else if (!(old->ce_flags & CE_CONFLICTED)) {
076b0adc
JS
1182 /*
1183 * See if we can re-use the old CE directly?
1184 * That way we get the uptodate stat info.
1185 *
7f8ab8dc
LT
1186 * This also removes the UPDATE flag on a match; otherwise
1187 * we will end up overwriting local changes in the work tree.
076b0adc
JS
1188 */
1189 if (same(old, merge)) {
eb7a2f1d 1190 copy_cache_entry(merge, old);
7f8ab8dc 1191 update = 0;
076b0adc 1192 } else {
203a2fe1
DB
1193 if (verify_uptodate(old, o))
1194 return -1;
32f54ca3
NTND
1195 if (ce_skip_worktree(old))
1196 update |= CE_SKIP_WORKTREE;
bc052d7f 1197 invalidate_ce_path(old, o);
076b0adc 1198 }
e11d7b59
JH
1199 } else {
1200 /*
1201 * Previously unmerged entry left as an existence
1202 * marker by read_index_unmerged();
1203 */
1204 invalidate_ce_path(old, o);
076b0adc
JS
1205 }
1206
7f8ab8dc 1207 add_entry(o, merge, update, CE_STAGEMASK);
076b0adc
JS
1208 return 1;
1209}
1210
1211static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1212 struct unpack_trees_options *o)
1213{
34110cd4
LT
1214 /* Did it exist in the index? */
1215 if (!old) {
08402b04 1216 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
203a2fe1 1217 return -1;
34110cd4
LT
1218 return 0;
1219 }
e11d7b59 1220 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
34110cd4
LT
1221 return -1;
1222 add_entry(o, ce, CE_REMOVE, 0);
bc052d7f 1223 invalidate_ce_path(ce, o);
076b0adc
JS
1224 return 1;
1225}
1226
7f7932ab 1227static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc 1228{
34110cd4 1229 add_entry(o, ce, 0, 0);
076b0adc
JS
1230 return 1;
1231}
1232
1233#if DBRT_DEBUG
1234static void show_stage_entry(FILE *o,
1235 const char *label, const struct cache_entry *ce)
1236{
1237 if (!ce)
1238 fprintf(o, "%s (missing)\n", label);
1239 else
1240 fprintf(o, "%s%06o %s %d\t%s\n",
1241 label,
7a51ed66 1242 ce->ce_mode,
076b0adc
JS
1243 sha1_to_hex(ce->sha1),
1244 ce_stage(ce),
1245 ce->name);
1246}
1247#endif
1248
34110cd4 1249int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
076b0adc
JS
1250{
1251 struct cache_entry *index;
1252 struct cache_entry *head;
1253 struct cache_entry *remote = stages[o->head_idx + 1];
1254 int count;
1255 int head_match = 0;
1256 int remote_match = 0;
076b0adc
JS
1257
1258 int df_conflict_head = 0;
1259 int df_conflict_remote = 0;
1260
1261 int any_anc_missing = 0;
1262 int no_anc_exists = 1;
1263 int i;
1264
1265 for (i = 1; i < o->head_idx; i++) {
4c4caafc 1266 if (!stages[i] || stages[i] == o->df_conflict_entry)
076b0adc 1267 any_anc_missing = 1;
4c4caafc 1268 else
076b0adc 1269 no_anc_exists = 0;
076b0adc
JS
1270 }
1271
1272 index = stages[0];
1273 head = stages[o->head_idx];
1274
1275 if (head == o->df_conflict_entry) {
1276 df_conflict_head = 1;
1277 head = NULL;
1278 }
1279
1280 if (remote == o->df_conflict_entry) {
1281 df_conflict_remote = 1;
1282 remote = NULL;
1283 }
1284
cee2d6ae
JH
1285 /*
1286 * First, if there's a #16 situation, note that to prevent #13
076b0adc
JS
1287 * and #14.
1288 */
1289 if (!same(remote, head)) {
1290 for (i = 1; i < o->head_idx; i++) {
1291 if (same(stages[i], head)) {
1292 head_match = i;
1293 }
1294 if (same(stages[i], remote)) {
1295 remote_match = i;
1296 }
1297 }
1298 }
1299
cee2d6ae
JH
1300 /*
1301 * We start with cases where the index is allowed to match
076b0adc
JS
1302 * something other than the head: #14(ALT) and #2ALT, where it
1303 * is permitted to match the result instead.
1304 */
1305 /* #14, #14ALT, #2ALT */
1306 if (remote && !df_conflict_head && head_match && !remote_match) {
1307 if (index && !same(index, remote) && !same(index, head))
8ccba008 1308 return o->gently ? -1 : reject_merge(index, o);
076b0adc
JS
1309 return merged_entry(remote, index, o);
1310 }
1311 /*
1312 * If we have an entry in the index cache, then we want to
1313 * make sure that it matches head.
1314 */
4e7c4571 1315 if (index && !same(index, head))
8ccba008 1316 return o->gently ? -1 : reject_merge(index, o);
076b0adc
JS
1317
1318 if (head) {
1319 /* #5ALT, #15 */
1320 if (same(head, remote))
1321 return merged_entry(head, index, o);
1322 /* #13, #3ALT */
1323 if (!df_conflict_remote && remote_match && !head_match)
1324 return merged_entry(head, index, o);
1325 }
1326
1327 /* #1 */
34110cd4 1328 if (!head && !remote && any_anc_missing)
076b0adc
JS
1329 return 0;
1330
cee2d6ae
JH
1331 /*
1332 * Under the "aggressive" rule, we resolve mostly trivial
076b0adc
JS
1333 * cases that we historically had git-merge-one-file resolve.
1334 */
1335 if (o->aggressive) {
cee2d6ae
JH
1336 int head_deleted = !head;
1337 int remote_deleted = !remote;
0cf73755 1338 struct cache_entry *ce = NULL;
4c4caafc
JH
1339
1340 if (index)
0cf73755 1341 ce = index;
4c4caafc 1342 else if (head)
0cf73755 1343 ce = head;
4c4caafc 1344 else if (remote)
0cf73755 1345 ce = remote;
4c4caafc
JH
1346 else {
1347 for (i = 1; i < o->head_idx; i++) {
1348 if (stages[i] && stages[i] != o->df_conflict_entry) {
0cf73755 1349 ce = stages[i];
4c4caafc
JH
1350 break;
1351 }
1352 }
1353 }
1354
076b0adc
JS
1355 /*
1356 * Deleted in both.
1357 * Deleted in one and unchanged in the other.
1358 */
1359 if ((head_deleted && remote_deleted) ||
1360 (head_deleted && remote && remote_match) ||
1361 (remote_deleted && head && head_match)) {
1362 if (index)
1363 return deleted_entry(index, index, o);
34110cd4 1364 if (ce && !head_deleted) {
08402b04 1365 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
203a2fe1
DB
1366 return -1;
1367 }
076b0adc
JS
1368 return 0;
1369 }
1370 /*
1371 * Added in both, identically.
1372 */
1373 if (no_anc_exists && head && remote && same(head, remote))
1374 return merged_entry(head, index, o);
1375
1376 }
1377
1378 /* Below are "no merge" cases, which require that the index be
1379 * up-to-date to avoid the files getting overwritten with
1380 * conflict resolution files.
1381 */
1382 if (index) {
203a2fe1
DB
1383 if (verify_uptodate(index, o))
1384 return -1;
076b0adc 1385 }
076b0adc
JS
1386
1387 o->nontrivial_merge = 1;
1388
ea4b52a8 1389 /* #2, #3, #4, #6, #7, #9, #10, #11. */
076b0adc
JS
1390 count = 0;
1391 if (!head_match || !remote_match) {
1392 for (i = 1; i < o->head_idx; i++) {
4c4caafc 1393 if (stages[i] && stages[i] != o->df_conflict_entry) {
7f7932ab 1394 keep_entry(stages[i], o);
076b0adc
JS
1395 count++;
1396 break;
1397 }
1398 }
1399 }
1400#if DBRT_DEBUG
1401 else {
1402 fprintf(stderr, "read-tree: warning #16 detected\n");
1403 show_stage_entry(stderr, "head ", stages[head_match]);
1404 show_stage_entry(stderr, "remote ", stages[remote_match]);
1405 }
1406#endif
7f7932ab
JH
1407 if (head) { count += keep_entry(head, o); }
1408 if (remote) { count += keep_entry(remote, o); }
076b0adc
JS
1409 return count;
1410}
1411
1412/*
1413 * Two-way merge.
1414 *
1415 * The rule is to "carry forward" what is in the index without losing
a75d7b54 1416 * information across a "fast-forward", favoring a successful merge
076b0adc
JS
1417 * over a merge failure when it makes sense. For details of the
1418 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1419 *
1420 */
34110cd4 1421int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
076b0adc
JS
1422{
1423 struct cache_entry *current = src[0];
b8ba1535
JH
1424 struct cache_entry *oldtree = src[1];
1425 struct cache_entry *newtree = src[2];
076b0adc
JS
1426
1427 if (o->merge_size != 2)
1428 return error("Cannot do a twoway merge of %d trees",
1429 o->merge_size);
1430
b8ba1535
JH
1431 if (oldtree == o->df_conflict_entry)
1432 oldtree = NULL;
1433 if (newtree == o->df_conflict_entry)
1434 newtree = NULL;
1435
076b0adc
JS
1436 if (current) {
1437 if ((!oldtree && !newtree) || /* 4 and 5 */
1438 (!oldtree && newtree &&
1439 same(current, newtree)) || /* 6 and 7 */
1440 (oldtree && newtree &&
1441 same(oldtree, newtree)) || /* 14 and 15 */
1442 (oldtree && newtree &&
b8ba1535 1443 !same(oldtree, newtree) && /* 18 and 19 */
076b0adc 1444 same(current, newtree))) {
7f7932ab 1445 return keep_entry(current, o);
076b0adc
JS
1446 }
1447 else if (oldtree && !newtree && same(current, oldtree)) {
1448 /* 10 or 11 */
1449 return deleted_entry(oldtree, current, o);
1450 }
1451 else if (oldtree && newtree &&
1452 same(current, oldtree) && !same(current, newtree)) {
1453 /* 20 or 21 */
1454 return merged_entry(newtree, current, o);
1455 }
1456 else {
1457 /* all other failures */
1458 if (oldtree)
8ccba008 1459 return o->gently ? -1 : reject_merge(oldtree, o);
076b0adc 1460 if (current)
8ccba008 1461 return o->gently ? -1 : reject_merge(current, o);
076b0adc 1462 if (newtree)
8ccba008 1463 return o->gently ? -1 : reject_merge(newtree, o);
076b0adc
JS
1464 return -1;
1465 }
1466 }
55218834
JH
1467 else if (newtree) {
1468 if (oldtree && !o->initial_checkout) {
1469 /*
1470 * deletion of the path was staged;
1471 */
1472 if (same(oldtree, newtree))
1473 return 1;
1474 return reject_merge(oldtree, o);
1475 }
076b0adc 1476 return merged_entry(newtree, current, o);
55218834 1477 }
d699676d 1478 return deleted_entry(oldtree, current, o);
076b0adc
JS
1479}
1480
1481/*
1482 * Bind merge.
1483 *
1484 * Keep the index entries at stage0, collapse stage1 but make sure
1485 * stage0 does not have anything there.
1486 */
1487int bind_merge(struct cache_entry **src,
34110cd4 1488 struct unpack_trees_options *o)
076b0adc
JS
1489{
1490 struct cache_entry *old = src[0];
1491 struct cache_entry *a = src[1];
1492
1493 if (o->merge_size != 1)
1494 return error("Cannot do a bind merge of %d trees\n",
1495 o->merge_size);
1496 if (a && old)
17e46426 1497 return o->gently ? -1 :
08353ebb 1498 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
076b0adc 1499 if (!a)
7f7932ab 1500 return keep_entry(old, o);
076b0adc
JS
1501 else
1502 return merged_entry(a, NULL, o);
1503}
1504
1505/*
1506 * One-way merge.
1507 *
1508 * The rule is:
1509 * - take the stat information from stage0, take the data from stage1
1510 */
34110cd4 1511int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
076b0adc
JS
1512{
1513 struct cache_entry *old = src[0];
1514 struct cache_entry *a = src[1];
1515
1516 if (o->merge_size != 1)
1517 return error("Cannot do a oneway merge of %d trees",
1518 o->merge_size);
1519
78d3b06e 1520 if (!a || a == o->df_conflict_entry)
076b0adc 1521 return deleted_entry(old, old, o);
34110cd4 1522
076b0adc 1523 if (old && same(old, a)) {
34110cd4 1524 int update = 0;
52030836 1525 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
076b0adc
JS
1526 struct stat st;
1527 if (lstat(old->name, &st) ||
56cac48c 1528 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
34110cd4 1529 update |= CE_UPDATE;
076b0adc 1530 }
34110cd4
LT
1531 add_entry(o, old, update, 0);
1532 return 0;
076b0adc
JS
1533 }
1534 return merged_entry(a, old, o);
1535}