do not overwrite files in leading path
[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 16 * situation better. See how "git checkout" and "git merge" replaces
dc1166e6 17 * them using setup_unpack_trees_porcelain(), 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.",
8ccba008 31
08402b04
MM
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
e294030f
MM
53void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
54 const char *cmd)
dc1166e6 55{
e294030f 56 const char **msgs = opts->msgs;
dc1166e6
MM
57 const char *msg;
58 char *tmp;
59 const char *cmd2 = strcmp(cmd, "checkout") ? cmd : "switch branches";
60 if (advice_commit_before_merge)
61 msg = "Your local changes to the following files would be overwritten by %s:\n%%s"
62 "Please, commit your changes or stash them before you can %s.";
63 else
64 msg = "Your local changes to the following files would be overwritten by %s:\n%%s";
65 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen(cmd2) - 2);
66 sprintf(tmp, msg, cmd, cmd2);
67 msgs[ERROR_WOULD_OVERWRITE] = tmp;
68 msgs[ERROR_NOT_UPTODATE_FILE] = tmp;
69
70 msgs[ERROR_NOT_UPTODATE_DIR] =
71 "Updating the following directories would lose untracked files in it:\n%s";
72
73 if (advice_commit_before_merge)
74 msg = "The following untracked working tree files would be %s by %s:\n%%s"
75 "Please move or remove them before you can %s.";
76 else
77 msg = "The following untracked working tree files would be %s by %s:\n%%s";
78 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("removed") + strlen(cmd2) - 4);
79 sprintf(tmp, msg, "removed", cmd, cmd2);
80 msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] = tmp;
81 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("overwritten") + strlen(cmd2) - 4);
82 sprintf(tmp, msg, "overwritten", cmd, cmd2);
83 msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] = tmp;
84
85 /*
86 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
87 * cannot easily display it as a list.
88 */
89 msgs[ERROR_BIND_OVERLAP] = "Entry '%s' overlaps with '%s'. Cannot bind.";
90
91 msgs[ERROR_SPARSE_NOT_UPTODATE_FILE] =
92 "Cannot update sparse checkout: the following entries are not up-to-date:\n%s";
93 msgs[ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN] =
94 "The following Working tree files would be overwritten by sparse checkout update:\n%s";
95 msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
96 "The following Working tree files would be removed by sparse checkout update:\n%s";
5e65ee35
MM
97
98 opts->show_all_errors = 1;
dc1166e6
MM
99}
100
34110cd4
LT
101static void add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
102 unsigned int set, unsigned int clear)
b48d5a05 103{
34110cd4
LT
104 unsigned int size = ce_size(ce);
105 struct cache_entry *new = xmalloc(size);
106
107 clear |= CE_HASHED | CE_UNHASHED;
108
700e66d6
NTND
109 if (set & CE_REMOVE)
110 set |= CE_WT_REMOVE;
111
34110cd4
LT
112 memcpy(new, ce, size);
113 new->next = NULL;
114 new->ce_flags = (new->ce_flags & ~clear) | set;
aab3b9a1 115 add_index_entry(&o->result, new, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
b48d5a05
LT
116}
117
e6c111b4
MM
118/*
119 * add error messages on path <path>
120 * corresponding to the type <e> with the message <msg>
121 * indicating if it should be display in porcelain or not
122 */
123static int add_rejected_path(struct unpack_trees_options *o,
124 enum unpack_trees_error_types e,
125 const char *path)
126{
127 struct rejected_paths_list *newentry;
e6c111b4
MM
128 if (!o->show_all_errors)
129 return error(ERRORMSG(o, e), path);
130
131 /*
132 * Otherwise, insert in a list for future display by
133 * display_error_msgs()
134 */
135 newentry = xmalloc(sizeof(struct rejected_paths_list));
136 newentry->path = (char *)path;
137 newentry->next = o->unpack_rejects[e];
138 o->unpack_rejects[e] = newentry;
139 return -1;
140}
141
142/*
143 * free all the structures allocated for the error <e>
144 */
145static void free_rejected_paths(struct unpack_trees_options *o,
146 enum unpack_trees_error_types e)
147{
148 while (o->unpack_rejects[e]) {
149 struct rejected_paths_list *del = o->unpack_rejects[e];
150 o->unpack_rejects[e] = o->unpack_rejects[e]->next;
151 free(del);
152 }
153 free(o->unpack_rejects[e]);
154}
155
156/*
157 * display all the error messages stored in a nice way
158 */
159static void display_error_msgs(struct unpack_trees_options *o)
160{
161 int e;
162 int something_displayed = 0;
163 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
164 if (o->unpack_rejects[e]) {
165 struct rejected_paths_list *rp;
166 struct strbuf path = STRBUF_INIT;
167 something_displayed = 1;
168 for (rp = o->unpack_rejects[e]; rp; rp = rp->next)
169 strbuf_addf(&path, "\t%s\n", rp->path);
170 error(ERRORMSG(o, e), path.buf);
171 strbuf_release(&path);
172 free_rejected_paths(o, e);
173 }
174 }
175 if (something_displayed)
176 printf("Aborting\n");
177}
178
78478927
KB
179/*
180 * Unlink the last component and schedule the leading directories for
181 * removal, such that empty directories get removed.
16da134b 182 */
c40641b7 183static void unlink_entry(struct cache_entry *ce)
16da134b 184{
f66caaf9 185 if (!check_leading_path(ce->name, ce_namelen(ce)))
16a4c617 186 return;
80d706af
PC
187 if (remove_or_warn(ce->ce_mode, ce->name))
188 return;
78478927 189 schedule_dir_for_removal(ce->name, ce_namelen(ce));
16da134b
JS
190}
191
16da134b 192static struct checkout state;
c4758d3c 193static int check_updates(struct unpack_trees_options *o)
16da134b 194{
96a02f8f 195 unsigned cnt = 0, total = 0;
dc6a0757 196 struct progress *progress = NULL;
34110cd4 197 struct index_state *index = &o->result;
33ecf7eb 198 int i;
c4758d3c 199 int errs = 0;
16da134b
JS
200
201 if (o->update && o->verbose_update) {
34110cd4
LT
202 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
203 struct cache_entry *ce = index->cache[cnt];
700e66d6 204 if (ce->ce_flags & (CE_UPDATE | CE_WT_REMOVE))
16da134b
JS
205 total++;
206 }
207
dc6a0757 208 progress = start_progress_delay("Checking out files",
e8548645 209 total, 50, 1);
16da134b
JS
210 cnt = 0;
211 }
212
66985e66
JH
213 if (o->update)
214 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
34110cd4
LT
215 for (i = 0; i < index->cache_nr; i++) {
216 struct cache_entry *ce = index->cache[i];
16da134b 217
e663db2f
NTND
218 if (ce->ce_flags & CE_WT_REMOVE) {
219 display_progress(progress, ++cnt);
220 if (o->update)
221 unlink_entry(ce);
222 continue;
223 }
1fa6ead4 224 }
36419c8e 225 remove_marked_cache_entries(&o->result);
78478927 226 remove_scheduled_dirs();
1fa6ead4
LT
227
228 for (i = 0; i < index->cache_nr; i++) {
229 struct cache_entry *ce = index->cache[i];
230
7a51ed66 231 if (ce->ce_flags & CE_UPDATE) {
1fa6ead4 232 display_progress(progress, ++cnt);
7a51ed66 233 ce->ce_flags &= ~CE_UPDATE;
16a4c617 234 if (o->update) {
c4758d3c 235 errs |= checkout_entry(ce, &state, NULL);
16a4c617 236 }
16da134b
JS
237 }
238 }
4d4fcc54 239 stop_progress(&progress);
66985e66
JH
240 if (o->update)
241 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
c4758d3c 242 return errs != 0;
16da134b
JS
243}
244
e800ec9d 245static int verify_uptodate_sparse(struct cache_entry *ce, struct unpack_trees_options *o);
08402b04 246static int verify_absent_sparse(struct cache_entry *ce, enum unpack_trees_error_types, struct unpack_trees_options *o);
e800ec9d
NTND
247
248static int will_have_skip_worktree(const struct cache_entry *ce, struct unpack_trees_options *o)
249{
250 const char *basename;
251
e800ec9d
NTND
252 basename = strrchr(ce->name, '/');
253 basename = basename ? basename+1 : ce->name;
254 return excluded_from_list(ce->name, ce_namelen(ce), basename, NULL, o->el) <= 0;
255}
256
257static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
258{
259 int was_skip_worktree = ce_skip_worktree(ce);
260
711f151a 261 if (!ce_stage(ce) && will_have_skip_worktree(ce, o))
e800ec9d
NTND
262 ce->ce_flags |= CE_SKIP_WORKTREE;
263 else
264 ce->ce_flags &= ~CE_SKIP_WORKTREE;
265
266 /*
eec3fc03
NTND
267 * if (!was_skip_worktree && !ce_skip_worktree()) {
268 * This is perfectly normal. Move on;
269 * }
e800ec9d 270 */
eec3fc03
NTND
271
272 /*
273 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
274 * area as a result of ce_skip_worktree() shortcuts in
700e66d6
NTND
275 * verify_absent() and verify_uptodate().
276 * Make sure they don't modify worktree if they are already
277 * outside checkout area
eec3fc03 278 */
700e66d6
NTND
279 if (was_skip_worktree && ce_skip_worktree(ce)) {
280 ce->ce_flags &= ~CE_UPDATE;
281
282 /*
283 * By default, when CE_REMOVE is on, CE_WT_REMOVE is also
284 * on to get that file removed from both index and worktree.
285 * If that file is already outside worktree area, don't
286 * bother remove it.
287 */
288 if (ce->ce_flags & CE_REMOVE)
289 ce->ce_flags &= ~CE_WT_REMOVE;
290 }
e800ec9d
NTND
291
292 if (!was_skip_worktree && ce_skip_worktree(ce)) {
293 /*
294 * If CE_UPDATE is set, verify_uptodate() must be called already
295 * also stat info may have lost after merged_entry() so calling
296 * verify_uptodate() again may fail
297 */
298 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
299 return -1;
300 ce->ce_flags |= CE_WT_REMOVE;
301 }
302 if (was_skip_worktree && !ce_skip_worktree(ce)) {
08402b04 303 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
e800ec9d
NTND
304 return -1;
305 ce->ce_flags |= CE_UPDATE;
306 }
307 return 0;
308}
309
34110cd4 310static inline int call_unpack_fn(struct cache_entry **src, struct unpack_trees_options *o)
01904572 311{
34110cd4
LT
312 int ret = o->fn(src, o);
313 if (ret > 0)
01904572 314 ret = 0;
01904572
LT
315 return ret;
316}
317
da165f47
JH
318static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
319{
320 ce->ce_flags |= CE_UNPACKED;
321
322 if (o->cache_bottom < o->src_index->cache_nr &&
323 o->src_index->cache[o->cache_bottom] == ce) {
324 int bottom = o->cache_bottom;
325 while (bottom < o->src_index->cache_nr &&
326 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
327 bottom++;
328 o->cache_bottom = bottom;
329 }
330}
331
332static void mark_all_ce_unused(struct index_state *index)
333{
334 int i;
335 for (i = 0; i < index->cache_nr; i++)
336 index->cache[i]->ce_flags &= ~CE_UNPACKED;
337}
338
339static int locate_in_src_index(struct cache_entry *ce,
340 struct unpack_trees_options *o)
341{
342 struct index_state *index = o->src_index;
343 int len = ce_namelen(ce);
344 int pos = index_name_pos(index, ce->name, len);
345 if (pos < 0)
346 pos = -1 - pos;
347 return pos;
348}
349
350/*
351 * We call unpack_index_entry() with an unmerged cache entry
352 * only in diff-index, and it wants a single callback. Skip
353 * the other unmerged entry with the same name.
354 */
355static void mark_ce_used_same_name(struct cache_entry *ce,
356 struct unpack_trees_options *o)
357{
358 struct index_state *index = o->src_index;
359 int len = ce_namelen(ce);
360 int pos;
361
362 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
363 struct cache_entry *next = index->cache[pos];
364 if (len != ce_namelen(next) ||
365 memcmp(ce->name, next->name, len))
366 break;
367 mark_ce_used(next, o);
368 }
369}
370
371static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
372{
373 const struct index_state *index = o->src_index;
374 int pos = o->cache_bottom;
375
376 while (pos < index->cache_nr) {
377 struct cache_entry *ce = index->cache[pos];
378 if (!(ce->ce_flags & CE_UNPACKED))
379 return ce;
380 pos++;
381 }
382 return NULL;
383}
384
385static void add_same_unmerged(struct cache_entry *ce,
386 struct unpack_trees_options *o)
387{
388 struct index_state *index = o->src_index;
389 int len = ce_namelen(ce);
390 int pos = index_name_pos(index, ce->name, len);
391
392 if (0 <= pos)
393 die("programming error in a caller of mark_ce_used_same_name");
394 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
395 struct cache_entry *next = index->cache[pos];
396 if (len != ce_namelen(next) ||
397 memcmp(ce->name, next->name, len))
398 break;
399 add_entry(o, next, 0, 0);
400 mark_ce_used(next, o);
401 }
402}
403
404static int unpack_index_entry(struct cache_entry *ce,
405 struct unpack_trees_options *o)
01904572 406{
66dbfd55 407 struct cache_entry *src[5] = { NULL };
da165f47 408 int ret;
34110cd4 409
66dbfd55
GV
410 src[0] = ce;
411
da165f47 412 mark_ce_used(ce, o);
01904572
LT
413 if (ce_stage(ce)) {
414 if (o->skip_unmerged) {
34110cd4
LT
415 add_entry(o, ce, 0, 0);
416 return 0;
01904572 417 }
01904572 418 }
da165f47
JH
419 ret = call_unpack_fn(src, o);
420 if (ce_stage(ce))
421 mark_ce_used_same_name(ce, o);
422 return ret;
01904572
LT
423}
424
730f7284
JH
425static int find_cache_pos(struct traverse_info *, const struct name_entry *);
426
427static void restore_cache_bottom(struct traverse_info *info, int bottom)
428{
429 struct unpack_trees_options *o = info->data;
430
431 if (o->diff_index_cached)
432 return;
433 o->cache_bottom = bottom;
434}
435
436static int switch_cache_bottom(struct traverse_info *info)
437{
438 struct unpack_trees_options *o = info->data;
439 int ret, pos;
440
441 if (o->diff_index_cached)
442 return 0;
443 ret = o->cache_bottom;
444 pos = find_cache_pos(info->prev, &info->name);
445
446 if (pos < -1)
447 o->cache_bottom = -2 - pos;
448 else if (pos < 0)
449 o->cache_bottom = o->src_index->cache_nr;
450 return ret;
01904572
LT
451}
452
2af202be 453static int traverse_trees_recursive(int n, unsigned long dirmask, unsigned long df_conflicts, struct name_entry *names, struct traverse_info *info)
16da134b 454{
730f7284 455 int i, ret, bottom;
ca885a4f 456 struct tree_desc t[MAX_UNPACK_TREES];
1ce584b0 457 void *buf[MAX_UNPACK_TREES];
01904572
LT
458 struct traverse_info newinfo;
459 struct name_entry *p;
460
461 p = names;
462 while (!p->mode)
463 p++;
464
465 newinfo = *info;
466 newinfo.prev = info;
467 newinfo.name = *p;
468 newinfo.pathlen += tree_entry_len(p->path, p->sha1) + 1;
469 newinfo.conflicts |= df_conflicts;
470
471 for (i = 0; i < n; i++, dirmask >>= 1) {
472 const unsigned char *sha1 = NULL;
473 if (dirmask & 1)
474 sha1 = names[i].sha1;
1ce584b0 475 buf[i] = fill_tree_descriptor(t+i, sha1);
01904572 476 }
730f7284
JH
477
478 bottom = switch_cache_bottom(&newinfo);
479 ret = traverse_trees(n, t, &newinfo);
480 restore_cache_bottom(&newinfo, bottom);
1ce584b0
JN
481
482 for (i = 0; i < n; i++)
483 free(buf[i]);
484
730f7284 485 return ret;
01904572
LT
486}
487
488/*
489 * Compare the traverse-path to the cache entry without actually
490 * having to generate the textual representation of the traverse
491 * path.
492 *
493 * NOTE! This *only* compares up to the size of the traverse path
494 * itself - the caller needs to do the final check for the cache
495 * entry having more data at the end!
496 */
497static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
498{
499 int len, pathlen, ce_len;
500 const char *ce_name;
501
502 if (info->prev) {
503 int cmp = do_compare_entry(ce, info->prev, &info->name);
504 if (cmp)
505 return cmp;
506 }
507 pathlen = info->pathlen;
508 ce_len = ce_namelen(ce);
509
510 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
511 if (ce_len < pathlen)
512 return -1;
513
514 ce_len -= pathlen;
515 ce_name = ce->name + pathlen;
516
517 len = tree_entry_len(n->path, n->sha1);
518 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
519}
520
521static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
522{
523 int cmp = do_compare_entry(ce, info, n);
524 if (cmp)
525 return cmp;
526
527 /*
528 * Even if the beginning compared identically, the ce should
529 * compare as bigger than a directory leading up to it!
530 */
531 return ce_namelen(ce) > traverse_path_len(info, n);
532}
533
da165f47
JH
534static int ce_in_traverse_path(const struct cache_entry *ce,
535 const struct traverse_info *info)
536{
537 if (!info->prev)
538 return 1;
539 if (do_compare_entry(ce, info->prev, &info->name))
540 return 0;
541 /*
542 * If ce (blob) is the same name as the path (which is a tree
543 * we will be descending into), it won't be inside it.
544 */
545 return (info->pathlen < ce_namelen(ce));
546}
547
01904572
LT
548static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
549{
550 int len = traverse_path_len(info, n);
551 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
552
553 ce->ce_mode = create_ce_mode(n->mode);
554 ce->ce_flags = create_ce_flags(len, stage);
555 hashcpy(ce->sha1, n->sha1);
556 make_traverse_path(ce->name, info, n);
557
558 return ce;
559}
560
c7cddc1a
RS
561static int unpack_nondirectories(int n, unsigned long mask,
562 unsigned long dirmask,
563 struct cache_entry **src,
564 const struct name_entry *names,
565 const struct traverse_info *info)
01904572
LT
566{
567 int i;
568 struct unpack_trees_options *o = info->data;
569 unsigned long conflicts;
570
571 /* Do we have *only* directories? Nothing to do */
572 if (mask == dirmask && !src[0])
573 return 0;
574
575 conflicts = info->conflicts;
576 if (o->merge)
577 conflicts >>= 1;
578 conflicts |= dirmask;
579
580 /*
581 * Ok, we've filled in up to any potential index entry in src[0],
582 * now do the rest.
583 */
584 for (i = 0; i < n; i++) {
585 int stage;
586 unsigned int bit = 1ul << i;
587 if (conflicts & bit) {
588 src[i + o->merge] = o->df_conflict_entry;
589 continue;
590 }
591 if (!(mask & bit))
592 continue;
593 if (!o->merge)
594 stage = 0;
595 else if (i + 1 < o->head_idx)
596 stage = 1;
597 else if (i + 1 > o->head_idx)
598 stage = 3;
599 else
600 stage = 2;
601 src[i + o->merge] = create_ce_entry(info, names + i, stage);
602 }
603
604 if (o->merge)
34110cd4 605 return call_unpack_fn(src, o);
01904572 606
01904572 607 for (i = 0; i < n; i++)
aab3b9a1
JH
608 if (src[i] && src[i] != o->df_conflict_entry)
609 add_entry(o, src[i], 0, 0);
01904572
LT
610 return 0;
611}
612
353c5eeb
JH
613static int unpack_failed(struct unpack_trees_options *o, const char *message)
614{
615 discard_index(&o->result);
616 if (!o->gently) {
617 if (message)
618 return error("%s", message);
619 return -1;
620 }
621 return -1;
622}
623
730f7284
JH
624/* NEEDSWORK: give this a better name and share with tree-walk.c */
625static int name_compare(const char *a, int a_len,
626 const char *b, int b_len)
627{
628 int len = (a_len < b_len) ? a_len : b_len;
629 int cmp = memcmp(a, b, len);
630 if (cmp)
631 return cmp;
632 return (a_len - b_len);
633}
634
635/*
636 * The tree traversal is looking at name p. If we have a matching entry,
637 * return it. If name p is a directory in the index, do not return
638 * anything, as we will want to match it when the traversal descends into
639 * the directory.
640 */
641static int find_cache_pos(struct traverse_info *info,
642 const struct name_entry *p)
643{
644 int pos;
645 struct unpack_trees_options *o = info->data;
646 struct index_state *index = o->src_index;
647 int pfxlen = info->pathlen;
648 int p_len = tree_entry_len(p->path, p->sha1);
649
650 for (pos = o->cache_bottom; pos < index->cache_nr; pos++) {
651 struct cache_entry *ce = index->cache[pos];
652 const char *ce_name, *ce_slash;
653 int cmp, ce_len;
654
e53e6b44
BD
655 if (ce->ce_flags & CE_UNPACKED) {
656 /*
657 * cache_bottom entry is already unpacked, so
658 * we can never match it; don't check it
659 * again.
660 */
661 if (pos == o->cache_bottom)
662 ++o->cache_bottom;
730f7284 663 continue;
e53e6b44
BD
664 }
665 if (!ce_in_traverse_path(ce, info))
730f7284
JH
666 continue;
667 ce_name = ce->name + pfxlen;
668 ce_slash = strchr(ce_name, '/');
669 if (ce_slash)
670 ce_len = ce_slash - ce_name;
671 else
672 ce_len = ce_namelen(ce) - pfxlen;
673 cmp = name_compare(p->path, p_len, ce_name, ce_len);
674 /*
675 * Exact match; if we have a directory we need to
676 * delay returning it.
677 */
678 if (!cmp)
679 return ce_slash ? -2 - pos : pos;
680 if (0 < cmp)
681 continue; /* keep looking */
682 /*
683 * ce_name sorts after p->path; could it be that we
684 * have files under p->path directory in the index?
685 * E.g. ce_name == "t-i", and p->path == "t"; we may
686 * have "t/a" in the index.
687 */
688 if (p_len < ce_len && !memcmp(ce_name, p->path, p_len) &&
689 ce_name[p_len] < '/')
690 continue; /* keep looking */
691 break;
692 }
693 return -1;
694}
695
696static struct cache_entry *find_cache_entry(struct traverse_info *info,
697 const struct name_entry *p)
698{
699 int pos = find_cache_pos(info, p);
700 struct unpack_trees_options *o = info->data;
701
702 if (0 <= pos)
703 return o->src_index->cache[pos];
704 else
705 return NULL;
706}
707
ba655da5
JH
708static void debug_path(struct traverse_info *info)
709{
710 if (info->prev) {
711 debug_path(info->prev);
712 if (*info->prev->name.path)
713 putchar('/');
714 }
715 printf("%s", info->name.path);
716}
717
718static void debug_name_entry(int i, struct name_entry *n)
719{
720 printf("ent#%d %06o %s\n", i,
721 n->path ? n->mode : 0,
722 n->path ? n->path : "(missing)");
723}
724
725static void debug_unpack_callback(int n,
726 unsigned long mask,
727 unsigned long dirmask,
728 struct name_entry *names,
729 struct traverse_info *info)
730{
731 int i;
732 printf("* unpack mask %lu, dirmask %lu, cnt %d ",
733 mask, dirmask, n);
734 debug_path(info);
735 putchar('\n');
736 for (i = 0; i < n; i++)
737 debug_name_entry(i, names + i);
738}
739
01904572
LT
740static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
741{
c7cddc1a 742 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
01904572 743 struct unpack_trees_options *o = info->data;
01904572
LT
744 const struct name_entry *p = names;
745
746 /* Find first entry with a real name (we could use "mask" too) */
747 while (!p->mode)
748 p++;
749
ba655da5
JH
750 if (o->debug_unpack)
751 debug_unpack_callback(n, mask, dirmask, names, info);
752
01904572
LT
753 /* Are we supposed to look at the index too? */
754 if (o->merge) {
da165f47 755 while (1) {
da165f47 756 int cmp;
730f7284
JH
757 struct cache_entry *ce;
758
759 if (o->diff_index_cached)
760 ce = next_cache_entry(o);
761 else
762 ce = find_cache_entry(info, p);
763
da165f47
JH
764 if (!ce)
765 break;
766 cmp = compare_entry(ce, info, p);
01904572
LT
767 if (cmp < 0) {
768 if (unpack_index_entry(ce, o) < 0)
353c5eeb 769 return unpack_failed(o, NULL);
01904572
LT
770 continue;
771 }
772 if (!cmp) {
773 if (ce_stage(ce)) {
774 /*
da165f47
JH
775 * If we skip unmerged index
776 * entries, we'll skip this
777 * entry *and* the tree
778 * entries associated with it!
01904572 779 */
34110cd4 780 if (o->skip_unmerged) {
da165f47 781 add_same_unmerged(ce, o);
01904572 782 return mask;
34110cd4 783 }
01904572
LT
784 }
785 src[0] = ce;
01904572
LT
786 }
787 break;
788 }
789 }
790
34110cd4 791 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
01904572
LT
792 return -1;
793
da165f47
JH
794 if (src[0]) {
795 if (ce_stage(src[0]))
796 mark_ce_used_same_name(src[0], o);
797 else
798 mark_ce_used(src[0], o);
799 }
800
01904572
LT
801 /* Now handle any directories.. */
802 if (dirmask) {
803 unsigned long conflicts = mask & ~dirmask;
804 if (o->merge) {
805 conflicts <<= 1;
806 if (src[0])
807 conflicts |= 1;
808 }
b65982b6
JH
809
810 /* special case: "diff-index --cached" looking at a tree */
811 if (o->diff_index_cached &&
812 n == 1 && dirmask == 1 && S_ISDIR(names->mode)) {
813 int matches;
814 matches = cache_tree_matches_traversal(o->src_index->cache_tree,
815 names, info);
816 /*
da165f47
JH
817 * Everything under the name matches; skip the
818 * entire hierarchy. diff_index_cached codepath
819 * special cases D/F conflicts in such a way that
820 * it does not do any look-ahead, so this is safe.
b65982b6
JH
821 */
822 if (matches) {
da165f47 823 o->cache_bottom += matches;
b65982b6
JH
824 return mask;
825 }
826 }
827
542c264b
JH
828 if (traverse_trees_recursive(n, dirmask, conflicts,
829 names, info) < 0)
830 return -1;
01904572
LT
831 return mask;
832 }
833
834 return mask;
835}
836
2e2b887d
JH
837/*
838 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
839 * resulting index, -2 on failure to reflect the changes to the work tree.
840 */
01904572
LT
841int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
842{
e800ec9d 843 int i, ret;
0fb1eaa8 844 static struct cache_entry *dfc;
08aefc9e 845 struct exclude_list el;
16da134b 846
ca885a4f
JH
847 if (len > MAX_UNPACK_TREES)
848 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
076b0adc 849 memset(&state, 0, sizeof(state));
16da134b
JS
850 state.base_dir = "";
851 state.force = 1;
852 state.quiet = 1;
853 state.refresh_cache = 1;
854
08aefc9e
NTND
855 memset(&el, 0, sizeof(el));
856 if (!core_apply_sparse_checkout || !o->update)
857 o->skip_sparse_checkout = 1;
858 if (!o->skip_sparse_checkout) {
859 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, NULL, &el, 0) < 0)
860 o->skip_sparse_checkout = 1;
861 else
862 o->el = &el;
863 }
864
34110cd4 865 memset(&o->result, 0, sizeof(o->result));
913e0e99 866 o->result.initialized = 1;
da165f47
JH
867 o->result.timestamp.sec = o->src_index->timestamp.sec;
868 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
16da134b 869 o->merge_size = len;
da165f47 870 mark_all_ce_unused(o->src_index);
0fb1eaa8
JH
871
872 if (!dfc)
13494ed1 873 dfc = xcalloc(1, cache_entry_size(0));
0fb1eaa8 874 o->df_conflict_entry = dfc;
16da134b
JS
875
876 if (len) {
01904572
LT
877 const char *prefix = o->prefix ? o->prefix : "";
878 struct traverse_info info;
879
880 setup_traverse_info(&info, prefix);
881 info.fn = unpack_callback;
882 info.data = o;
e6c111b4 883 info.show_all_errors = o->show_all_errors;
01904572 884
da165f47
JH
885 if (o->prefix) {
886 /*
887 * Unpack existing index entries that sort before the
888 * prefix the tree is spliced into. Note that o->merge
889 * is always true in this case.
890 */
891 while (1) {
892 struct cache_entry *ce = next_cache_entry(o);
893 if (!ce)
894 break;
895 if (ce_in_traverse_path(ce, &info))
896 break;
897 if (unpack_index_entry(ce, o) < 0)
898 goto return_failed;
899 }
08aefc9e 900 }
da165f47 901
01904572 902 if (traverse_trees(len, t, &info) < 0)
da165f47 903 goto return_failed;
16da134b
JS
904 }
905
01904572
LT
906 /* Any left-over entries in the index? */
907 if (o->merge) {
da165f47
JH
908 while (1) {
909 struct cache_entry *ce = next_cache_entry(o);
910 if (!ce)
911 break;
01904572 912 if (unpack_index_entry(ce, o) < 0)
da165f47 913 goto return_failed;
17e46426 914 }
17e46426 915 }
da165f47 916 mark_all_ce_unused(o->src_index);
16da134b 917
08aefc9e
NTND
918 if (o->trivial_merges_only && o->nontrivial_merge) {
919 ret = unpack_failed(o, "Merge requires file-level merging");
920 goto done;
921 }
01904572 922
e800ec9d 923 if (!o->skip_sparse_checkout) {
9e1afb16 924 int empty_worktree = 1;
e800ec9d
NTND
925 for (i = 0;i < o->result.cache_nr;i++) {
926 struct cache_entry *ce = o->result.cache[i];
927
928 if (apply_sparse_checkout(ce, o)) {
929 ret = -1;
930 goto done;
931 }
eec3fc03 932 if (!ce_skip_worktree(ce))
9e1afb16 933 empty_worktree = 0;
f1f523ea 934
e800ec9d 935 }
9e1afb16
NTND
936 if (o->result.cache_nr && empty_worktree) {
937 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
938 goto done;
939 }
e800ec9d 940 }
01904572 941
34110cd4 942 o->src_index = NULL;
2e2b887d 943 ret = check_updates(o) ? (-2) : 0;
34110cd4
LT
944 if (o->dst_index)
945 *o->dst_index = o->result;
08aefc9e
NTND
946
947done:
948 for (i = 0;i < el.nr;i++)
949 free(el.excludes[i]);
950 if (el.excludes)
951 free(el.excludes);
952
2e2b887d 953 return ret;
da165f47
JH
954
955return_failed:
e6c111b4
MM
956 if (o->show_all_errors)
957 display_error_msgs(o);
da165f47 958 mark_all_ce_unused(o->src_index);
026680f8
JH
959 ret = unpack_failed(o, NULL);
960 goto done;
16da134b 961}
076b0adc
JS
962
963/* Here come the merge functions */
964
8ccba008 965static int reject_merge(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc 966{
e6c111b4 967 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
076b0adc
JS
968}
969
970static int same(struct cache_entry *a, struct cache_entry *b)
971{
972 if (!!a != !!b)
973 return 0;
974 if (!a && !b)
975 return 1;
e11d7b59
JH
976 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
977 return 0;
076b0adc 978 return a->ce_mode == b->ce_mode &&
a89fccd2 979 !hashcmp(a->sha1, b->sha1);
076b0adc
JS
980}
981
982
983/*
984 * When a CE gets turned into an unmerged entry, we
985 * want it to be up-to-date
986 */
35a5aa79
NTND
987static int verify_uptodate_1(struct cache_entry *ce,
988 struct unpack_trees_options *o,
08402b04 989 enum unpack_trees_error_types error_type)
076b0adc
JS
990{
991 struct stat st;
992
aecda37c 993 if (o->index_only || (!((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce)) && (o->reset || ce_uptodate(ce))))
203a2fe1 994 return 0;
076b0adc
JS
995
996 if (!lstat(ce->name, &st)) {
56cac48c 997 unsigned changed = ie_match_stat(o->src_index, ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
076b0adc 998 if (!changed)
203a2fe1 999 return 0;
936492d3
JH
1000 /*
1001 * NEEDSWORK: the current default policy is to allow
1002 * submodule to be out of sync wrt the supermodule
1003 * index. This needs to be tightened later for
1004 * submodules that are marked to be automatically
1005 * checked out.
1006 */
7a51ed66 1007 if (S_ISGITLINK(ce->ce_mode))
203a2fe1 1008 return 0;
076b0adc
JS
1009 errno = 0;
1010 }
076b0adc 1011 if (errno == ENOENT)
203a2fe1 1012 return 0;
17e46426 1013 return o->gently ? -1 :
e6c111b4 1014 add_rejected_path(o, error_type, ce->name);
35a5aa79
NTND
1015}
1016
1017static int verify_uptodate(struct cache_entry *ce,
1018 struct unpack_trees_options *o)
1019{
f1f523ea
NTND
1020 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
1021 return 0;
08402b04 1022 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
076b0adc
JS
1023}
1024
e800ec9d
NTND
1025static int verify_uptodate_sparse(struct cache_entry *ce,
1026 struct unpack_trees_options *o)
1027{
08402b04 1028 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
076b0adc
JS
1029}
1030
bc052d7f 1031static void invalidate_ce_path(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc
JS
1032{
1033 if (ce)
34110cd4 1034 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
076b0adc
JS
1035}
1036
0cf73755
SV
1037/*
1038 * Check that checking out ce->sha1 in subdir ce->name is not
1039 * going to overwrite any working files.
1040 *
1041 * Currently, git does not checkout subprojects during a superproject
1042 * checkout, so it is not going to overwrite anything.
1043 */
08402b04
MM
1044static int verify_clean_submodule(struct cache_entry *ce,
1045 enum unpack_trees_error_types error_type,
0cf73755
SV
1046 struct unpack_trees_options *o)
1047{
1048 return 0;
1049}
1050
08402b04
MM
1051static int verify_clean_subdirectory(struct cache_entry *ce,
1052 enum unpack_trees_error_types error_type,
c8193534
JH
1053 struct unpack_trees_options *o)
1054{
1055 /*
0cf73755 1056 * we are about to extract "ce->name"; we would not want to lose
c8193534
JH
1057 * anything in the existing directory there.
1058 */
1059 int namelen;
7b9e3ce0 1060 int i;
c8193534
JH
1061 struct dir_struct d;
1062 char *pathbuf;
1063 int cnt = 0;
0cf73755
SV
1064 unsigned char sha1[20];
1065
7a51ed66 1066 if (S_ISGITLINK(ce->ce_mode) &&
0cf73755
SV
1067 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1068 /* If we are not going to update the submodule, then
1069 * we don't care.
1070 */
1071 if (!hashcmp(sha1, ce->sha1))
1072 return 0;
08402b04 1073 return verify_clean_submodule(ce, error_type, o);
0cf73755 1074 }
c8193534
JH
1075
1076 /*
1077 * First let's make sure we do not have a local modification
1078 * in that directory.
1079 */
0cf73755 1080 namelen = strlen(ce->name);
da165f47
JH
1081 for (i = locate_in_src_index(ce, o);
1082 i < o->src_index->cache_nr;
1083 i++) {
837e5fe9
CB
1084 struct cache_entry *ce2 = o->src_index->cache[i];
1085 int len = ce_namelen(ce2);
c8193534 1086 if (len < namelen ||
837e5fe9
CB
1087 strncmp(ce->name, ce2->name, namelen) ||
1088 ce2->name[namelen] != '/')
c8193534
JH
1089 break;
1090 /*
da165f47
JH
1091 * ce2->name is an entry in the subdirectory to be
1092 * removed.
c8193534 1093 */
837e5fe9
CB
1094 if (!ce_stage(ce2)) {
1095 if (verify_uptodate(ce2, o))
203a2fe1 1096 return -1;
837e5fe9 1097 add_entry(o, ce2, CE_REMOVE, 0);
da165f47 1098 mark_ce_used(ce2, o);
c8193534
JH
1099 }
1100 cnt++;
1101 }
1102
1103 /*
1104 * Then we need to make sure that we do not lose a locally
1105 * present file that is not ignored.
1106 */
1107 pathbuf = xmalloc(namelen + 2);
0cf73755 1108 memcpy(pathbuf, ce->name, namelen);
c8193534
JH
1109 strcpy(pathbuf+namelen, "/");
1110
1111 memset(&d, 0, sizeof(d));
1112 if (o->dir)
1113 d.exclude_per_dir = o->dir->exclude_per_dir;
dba2e203 1114 i = read_directory(&d, pathbuf, namelen+1, NULL);
c8193534 1115 if (i)
17e46426 1116 return o->gently ? -1 :
e6c111b4 1117 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
c8193534
JH
1118 free(pathbuf);
1119 return cnt;
1120}
1121
32260ad5
LT
1122/*
1123 * This gets called when there was no index entry for the tree entry 'dst',
1124 * but we found a file in the working tree that 'lstat()' said was fine,
1125 * and we're on a case-insensitive filesystem.
1126 *
1127 * See if we can find a case-insensitive match in the index that also
1128 * matches the stat information, and assume it's that other file!
1129 */
a9307f5a 1130static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
32260ad5
LT
1131{
1132 struct cache_entry *src;
1133
a9307f5a 1134 src = index_name_exists(o->src_index, name, len, 1);
56cac48c 1135 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
32260ad5
LT
1136}
1137
a9307f5a
CB
1138static int check_ok_to_remove(const char *name, int len, int dtype,
1139 struct cache_entry *ce, struct stat *st,
1140 enum unpack_trees_error_types error_type,
1141 struct unpack_trees_options *o)
1142{
1143 struct cache_entry *result;
1144
1145 /*
1146 * It may be that the 'lstat()' succeeded even though
1147 * target 'ce' was absent, because there is an old
1148 * entry that is different only in case..
1149 *
1150 * Ignore that lstat() if it matches.
1151 */
1152 if (ignore_case && icase_exists(o, name, len, st))
1153 return 0;
1154
1155 if (o->dir && excluded(o->dir, name, &dtype))
1156 /*
1157 * ce->name is explicitly excluded, so it is Ok to
1158 * overwrite it.
1159 */
1160 return 0;
1161 if (S_ISDIR(st->st_mode)) {
1162 /*
1163 * We are checking out path "foo" and
1164 * found "foo/." in the working tree.
1165 * This is tricky -- if we have modified
1166 * files that are in "foo/" we would lose
1167 * them.
1168 */
1169 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1170 return -1;
1171 return 0;
1172 }
1173
1174 /*
1175 * The previous round may already have decided to
1176 * delete this path, which is in a subdirectory that
1177 * is being replaced with a blob.
1178 */
1179 result = index_name_exists(&o->result, name, len, 0);
1180 if (result) {
1181 if (result->ce_flags & CE_REMOVE)
1182 return 0;
1183 }
1184
1185 return o->gently ? -1 :
1186 add_rejected_path(o, error_type, name);
1187}
1188
076b0adc
JS
1189/*
1190 * We do not want to remove or overwrite a working tree file that
f8a9d428 1191 * is not tracked, unless it is ignored.
076b0adc 1192 */
08402b04
MM
1193static int verify_absent_1(struct cache_entry *ce,
1194 enum unpack_trees_error_types error_type,
1195 struct unpack_trees_options *o)
076b0adc 1196{
f66caaf9 1197 int len;
076b0adc
JS
1198 struct stat st;
1199
1200 if (o->index_only || o->reset || !o->update)
203a2fe1 1201 return 0;
c8193534 1202
f66caaf9
CB
1203 len = check_leading_path(ce->name, ce_namelen(ce));
1204 if (!len)
203a2fe1 1205 return 0;
f66caaf9
CB
1206 else if (len > 0) {
1207 char path[PATH_MAX + 1];
1208 memcpy(path, ce->name, len);
1209 path[len] = 0;
1210 lstat(path, &st);
ec0603e1 1211
f66caaf9
CB
1212 return check_ok_to_remove(path, len, DT_UNKNOWN, NULL, &st,
1213 error_type, o);
1214 } else if (!lstat(ce->name, &st))
a9307f5a
CB
1215 return check_ok_to_remove(ce->name, ce_namelen(ce),
1216 ce_to_dtype(ce), ce, &st,
1217 error_type, o);
f66caaf9 1218
203a2fe1 1219 return 0;
076b0adc 1220}
a9307f5a 1221
08402b04
MM
1222static int verify_absent(struct cache_entry *ce,
1223 enum unpack_trees_error_types error_type,
35a5aa79
NTND
1224 struct unpack_trees_options *o)
1225{
f1f523ea
NTND
1226 if (!o->skip_sparse_checkout && will_have_skip_worktree(ce, o))
1227 return 0;
08402b04 1228 return verify_absent_1(ce, error_type, o);
35a5aa79 1229}
076b0adc 1230
08402b04
MM
1231static int verify_absent_sparse(struct cache_entry *ce,
1232 enum unpack_trees_error_types error_type,
e800ec9d
NTND
1233 struct unpack_trees_options *o)
1234{
08402b04
MM
1235 enum unpack_trees_error_types orphaned_error = error_type;
1236 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1237 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1238
1239 return verify_absent_1(ce, orphaned_error, o);
e800ec9d 1240}
076b0adc
JS
1241
1242static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
1243 struct unpack_trees_options *o)
1244{
7f8ab8dc
LT
1245 int update = CE_UPDATE;
1246
e11d7b59 1247 if (!old) {
08402b04 1248 if (verify_absent(merge, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
e11d7b59 1249 return -1;
74da98f9
NTND
1250 if (!o->skip_sparse_checkout && will_have_skip_worktree(merge, o))
1251 update |= CE_SKIP_WORKTREE;
e11d7b59
JH
1252 invalidate_ce_path(merge, o);
1253 } else if (!(old->ce_flags & CE_CONFLICTED)) {
076b0adc
JS
1254 /*
1255 * See if we can re-use the old CE directly?
1256 * That way we get the uptodate stat info.
1257 *
7f8ab8dc
LT
1258 * This also removes the UPDATE flag on a match; otherwise
1259 * we will end up overwriting local changes in the work tree.
076b0adc
JS
1260 */
1261 if (same(old, merge)) {
eb7a2f1d 1262 copy_cache_entry(merge, old);
7f8ab8dc 1263 update = 0;
076b0adc 1264 } else {
203a2fe1
DB
1265 if (verify_uptodate(old, o))
1266 return -1;
32f54ca3
NTND
1267 if (ce_skip_worktree(old))
1268 update |= CE_SKIP_WORKTREE;
bc052d7f 1269 invalidate_ce_path(old, o);
076b0adc 1270 }
e11d7b59
JH
1271 } else {
1272 /*
1273 * Previously unmerged entry left as an existence
1274 * marker by read_index_unmerged();
1275 */
1276 invalidate_ce_path(old, o);
076b0adc
JS
1277 }
1278
7f8ab8dc 1279 add_entry(o, merge, update, CE_STAGEMASK);
076b0adc
JS
1280 return 1;
1281}
1282
1283static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
1284 struct unpack_trees_options *o)
1285{
34110cd4
LT
1286 /* Did it exist in the index? */
1287 if (!old) {
08402b04 1288 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
203a2fe1 1289 return -1;
34110cd4
LT
1290 return 0;
1291 }
e11d7b59 1292 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
34110cd4
LT
1293 return -1;
1294 add_entry(o, ce, CE_REMOVE, 0);
bc052d7f 1295 invalidate_ce_path(ce, o);
076b0adc
JS
1296 return 1;
1297}
1298
7f7932ab 1299static int keep_entry(struct cache_entry *ce, struct unpack_trees_options *o)
076b0adc 1300{
34110cd4 1301 add_entry(o, ce, 0, 0);
076b0adc
JS
1302 return 1;
1303}
1304
1305#if DBRT_DEBUG
1306static void show_stage_entry(FILE *o,
1307 const char *label, const struct cache_entry *ce)
1308{
1309 if (!ce)
1310 fprintf(o, "%s (missing)\n", label);
1311 else
1312 fprintf(o, "%s%06o %s %d\t%s\n",
1313 label,
7a51ed66 1314 ce->ce_mode,
076b0adc
JS
1315 sha1_to_hex(ce->sha1),
1316 ce_stage(ce),
1317 ce->name);
1318}
1319#endif
1320
34110cd4 1321int threeway_merge(struct cache_entry **stages, struct unpack_trees_options *o)
076b0adc
JS
1322{
1323 struct cache_entry *index;
1324 struct cache_entry *head;
1325 struct cache_entry *remote = stages[o->head_idx + 1];
1326 int count;
1327 int head_match = 0;
1328 int remote_match = 0;
076b0adc
JS
1329
1330 int df_conflict_head = 0;
1331 int df_conflict_remote = 0;
1332
1333 int any_anc_missing = 0;
1334 int no_anc_exists = 1;
1335 int i;
1336
1337 for (i = 1; i < o->head_idx; i++) {
4c4caafc 1338 if (!stages[i] || stages[i] == o->df_conflict_entry)
076b0adc 1339 any_anc_missing = 1;
4c4caafc 1340 else
076b0adc 1341 no_anc_exists = 0;
076b0adc
JS
1342 }
1343
1344 index = stages[0];
1345 head = stages[o->head_idx];
1346
1347 if (head == o->df_conflict_entry) {
1348 df_conflict_head = 1;
1349 head = NULL;
1350 }
1351
1352 if (remote == o->df_conflict_entry) {
1353 df_conflict_remote = 1;
1354 remote = NULL;
1355 }
1356
cee2d6ae
JH
1357 /*
1358 * First, if there's a #16 situation, note that to prevent #13
076b0adc
JS
1359 * and #14.
1360 */
1361 if (!same(remote, head)) {
1362 for (i = 1; i < o->head_idx; i++) {
1363 if (same(stages[i], head)) {
1364 head_match = i;
1365 }
1366 if (same(stages[i], remote)) {
1367 remote_match = i;
1368 }
1369 }
1370 }
1371
cee2d6ae
JH
1372 /*
1373 * We start with cases where the index is allowed to match
076b0adc
JS
1374 * something other than the head: #14(ALT) and #2ALT, where it
1375 * is permitted to match the result instead.
1376 */
1377 /* #14, #14ALT, #2ALT */
1378 if (remote && !df_conflict_head && head_match && !remote_match) {
1379 if (index && !same(index, remote) && !same(index, head))
8ccba008 1380 return o->gently ? -1 : reject_merge(index, o);
076b0adc
JS
1381 return merged_entry(remote, index, o);
1382 }
1383 /*
1384 * If we have an entry in the index cache, then we want to
1385 * make sure that it matches head.
1386 */
4e7c4571 1387 if (index && !same(index, head))
8ccba008 1388 return o->gently ? -1 : reject_merge(index, o);
076b0adc
JS
1389
1390 if (head) {
1391 /* #5ALT, #15 */
1392 if (same(head, remote))
1393 return merged_entry(head, index, o);
1394 /* #13, #3ALT */
1395 if (!df_conflict_remote && remote_match && !head_match)
1396 return merged_entry(head, index, o);
1397 }
1398
1399 /* #1 */
34110cd4 1400 if (!head && !remote && any_anc_missing)
076b0adc
JS
1401 return 0;
1402
cee2d6ae
JH
1403 /*
1404 * Under the "aggressive" rule, we resolve mostly trivial
076b0adc
JS
1405 * cases that we historically had git-merge-one-file resolve.
1406 */
1407 if (o->aggressive) {
cee2d6ae
JH
1408 int head_deleted = !head;
1409 int remote_deleted = !remote;
0cf73755 1410 struct cache_entry *ce = NULL;
4c4caafc
JH
1411
1412 if (index)
0cf73755 1413 ce = index;
4c4caafc 1414 else if (head)
0cf73755 1415 ce = head;
4c4caafc 1416 else if (remote)
0cf73755 1417 ce = remote;
4c4caafc
JH
1418 else {
1419 for (i = 1; i < o->head_idx; i++) {
1420 if (stages[i] && stages[i] != o->df_conflict_entry) {
0cf73755 1421 ce = stages[i];
4c4caafc
JH
1422 break;
1423 }
1424 }
1425 }
1426
076b0adc
JS
1427 /*
1428 * Deleted in both.
1429 * Deleted in one and unchanged in the other.
1430 */
1431 if ((head_deleted && remote_deleted) ||
1432 (head_deleted && remote && remote_match) ||
1433 (remote_deleted && head && head_match)) {
1434 if (index)
1435 return deleted_entry(index, index, o);
34110cd4 1436 if (ce && !head_deleted) {
08402b04 1437 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
203a2fe1
DB
1438 return -1;
1439 }
076b0adc
JS
1440 return 0;
1441 }
1442 /*
1443 * Added in both, identically.
1444 */
1445 if (no_anc_exists && head && remote && same(head, remote))
1446 return merged_entry(head, index, o);
1447
1448 }
1449
1450 /* Below are "no merge" cases, which require that the index be
1451 * up-to-date to avoid the files getting overwritten with
1452 * conflict resolution files.
1453 */
1454 if (index) {
203a2fe1
DB
1455 if (verify_uptodate(index, o))
1456 return -1;
076b0adc 1457 }
076b0adc
JS
1458
1459 o->nontrivial_merge = 1;
1460
ea4b52a8 1461 /* #2, #3, #4, #6, #7, #9, #10, #11. */
076b0adc
JS
1462 count = 0;
1463 if (!head_match || !remote_match) {
1464 for (i = 1; i < o->head_idx; i++) {
4c4caafc 1465 if (stages[i] && stages[i] != o->df_conflict_entry) {
7f7932ab 1466 keep_entry(stages[i], o);
076b0adc
JS
1467 count++;
1468 break;
1469 }
1470 }
1471 }
1472#if DBRT_DEBUG
1473 else {
1474 fprintf(stderr, "read-tree: warning #16 detected\n");
1475 show_stage_entry(stderr, "head ", stages[head_match]);
1476 show_stage_entry(stderr, "remote ", stages[remote_match]);
1477 }
1478#endif
7f7932ab
JH
1479 if (head) { count += keep_entry(head, o); }
1480 if (remote) { count += keep_entry(remote, o); }
076b0adc
JS
1481 return count;
1482}
1483
1484/*
1485 * Two-way merge.
1486 *
1487 * The rule is to "carry forward" what is in the index without losing
a75d7b54 1488 * information across a "fast-forward", favoring a successful merge
076b0adc
JS
1489 * over a merge failure when it makes sense. For details of the
1490 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1491 *
1492 */
34110cd4 1493int twoway_merge(struct cache_entry **src, struct unpack_trees_options *o)
076b0adc
JS
1494{
1495 struct cache_entry *current = src[0];
b8ba1535
JH
1496 struct cache_entry *oldtree = src[1];
1497 struct cache_entry *newtree = src[2];
076b0adc
JS
1498
1499 if (o->merge_size != 2)
1500 return error("Cannot do a twoway merge of %d trees",
1501 o->merge_size);
1502
b8ba1535
JH
1503 if (oldtree == o->df_conflict_entry)
1504 oldtree = NULL;
1505 if (newtree == o->df_conflict_entry)
1506 newtree = NULL;
1507
076b0adc
JS
1508 if (current) {
1509 if ((!oldtree && !newtree) || /* 4 and 5 */
1510 (!oldtree && newtree &&
1511 same(current, newtree)) || /* 6 and 7 */
1512 (oldtree && newtree &&
1513 same(oldtree, newtree)) || /* 14 and 15 */
1514 (oldtree && newtree &&
b8ba1535 1515 !same(oldtree, newtree) && /* 18 and 19 */
076b0adc 1516 same(current, newtree))) {
7f7932ab 1517 return keep_entry(current, o);
076b0adc
JS
1518 }
1519 else if (oldtree && !newtree && same(current, oldtree)) {
1520 /* 10 or 11 */
1521 return deleted_entry(oldtree, current, o);
1522 }
1523 else if (oldtree && newtree &&
1524 same(current, oldtree) && !same(current, newtree)) {
1525 /* 20 or 21 */
1526 return merged_entry(newtree, current, o);
1527 }
1528 else {
1529 /* all other failures */
1530 if (oldtree)
8ccba008 1531 return o->gently ? -1 : reject_merge(oldtree, o);
076b0adc 1532 if (current)
8ccba008 1533 return o->gently ? -1 : reject_merge(current, o);
076b0adc 1534 if (newtree)
8ccba008 1535 return o->gently ? -1 : reject_merge(newtree, o);
076b0adc
JS
1536 return -1;
1537 }
1538 }
55218834
JH
1539 else if (newtree) {
1540 if (oldtree && !o->initial_checkout) {
1541 /*
1542 * deletion of the path was staged;
1543 */
1544 if (same(oldtree, newtree))
1545 return 1;
1546 return reject_merge(oldtree, o);
1547 }
076b0adc 1548 return merged_entry(newtree, current, o);
55218834 1549 }
d699676d 1550 return deleted_entry(oldtree, current, o);
076b0adc
JS
1551}
1552
1553/*
1554 * Bind merge.
1555 *
1556 * Keep the index entries at stage0, collapse stage1 but make sure
1557 * stage0 does not have anything there.
1558 */
1559int bind_merge(struct cache_entry **src,
34110cd4 1560 struct unpack_trees_options *o)
076b0adc
JS
1561{
1562 struct cache_entry *old = src[0];
1563 struct cache_entry *a = src[1];
1564
1565 if (o->merge_size != 1)
1566 return error("Cannot do a bind merge of %d trees\n",
1567 o->merge_size);
1568 if (a && old)
17e46426 1569 return o->gently ? -1 :
08353ebb 1570 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
076b0adc 1571 if (!a)
7f7932ab 1572 return keep_entry(old, o);
076b0adc
JS
1573 else
1574 return merged_entry(a, NULL, o);
1575}
1576
1577/*
1578 * One-way merge.
1579 *
1580 * The rule is:
1581 * - take the stat information from stage0, take the data from stage1
1582 */
34110cd4 1583int oneway_merge(struct cache_entry **src, struct unpack_trees_options *o)
076b0adc
JS
1584{
1585 struct cache_entry *old = src[0];
1586 struct cache_entry *a = src[1];
1587
1588 if (o->merge_size != 1)
1589 return error("Cannot do a oneway merge of %d trees",
1590 o->merge_size);
1591
78d3b06e 1592 if (!a || a == o->df_conflict_entry)
076b0adc 1593 return deleted_entry(old, old, o);
34110cd4 1594
076b0adc 1595 if (old && same(old, a)) {
34110cd4 1596 int update = 0;
52030836 1597 if (o->reset && !ce_uptodate(old) && !ce_skip_worktree(old)) {
076b0adc
JS
1598 struct stat st;
1599 if (lstat(old->name, &st) ||
56cac48c 1600 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
34110cd4 1601 update |= CE_UPDATE;
076b0adc 1602 }
34110cd4
LT
1603 add_entry(o, old, update, 0);
1604 return 0;
076b0adc
JS
1605 }
1606 return merged_entry(a, old, o);
1607}