1#define NO_THE_INDEX_COMPATIBILITY_MACROS
2#include "cache.h"
3#include "dir.h"
4#include "tree.h"
5#include "tree-walk.h"
6#include "cache-tree.h"
7#include "unpack-trees.h"
8#include "progress.h"
9#include "refs.h"
10#include "attr.h"
11
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
16 * situation better. See how "git checkout" and "git merge" replaces
17 * them using setup_unpack_trees_porcelain(), for example.
18 */
19static const char *unpack_plumbing_errors[NB_UNPACK_TREES_ERROR_TYPES] = {
20 /* ERROR_WOULD_OVERWRITE */
21 "Entry '%s' would be overwritten by merge. Cannot merge.",
22
23 /* ERROR_NOT_UPTODATE_FILE */
24 "Entry '%s' not uptodate. Cannot merge.",
25
26 /* ERROR_NOT_UPTODATE_DIR */
27 "Updating '%s' would lose untracked files in it",
28
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.",
34
35 /* ERROR_BIND_OVERLAP */
36 "Entry '%s' overlaps with '%s'. Cannot bind.",
37
38 /* ERROR_SPARSE_NOT_UPTODATE_FILE */
39 "Entry '%s' not uptodate. Cannot update sparse checkout.",
40
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.",
46};
47
48#define ERRORMSG(o,type) \
49 ( ((o) && (o)->msgs[(type)]) \
50 ? ((o)->msgs[(type)]) \
51 : (unpack_plumbing_errors[(type)]) )
52
53void setup_unpack_trees_porcelain(struct unpack_trees_options *opts,
54 const char *cmd)
55{
56 int i;
57 const char **msgs = opts->msgs;
58 const char *msg;
59 char *tmp;
60 const char *cmd2 = strcmp(cmd, "checkout") ? cmd : "switch branches";
61 if (advice_commit_before_merge)
62 msg = "Your local changes to the following files would be overwritten by %s:\n%%s"
63 "Please, commit your changes or stash them before you can %s.";
64 else
65 msg = "Your local changes to the following files would be overwritten by %s:\n%%s";
66 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen(cmd2) - 2);
67 sprintf(tmp, msg, cmd, cmd2);
68 msgs[ERROR_WOULD_OVERWRITE] = tmp;
69 msgs[ERROR_NOT_UPTODATE_FILE] = tmp;
70
71 msgs[ERROR_NOT_UPTODATE_DIR] =
72 "Updating the following directories would lose untracked files in it:\n%s";
73
74 if (advice_commit_before_merge)
75 msg = "The following untracked working tree files would be %s by %s:\n%%s"
76 "Please move or remove them before you can %s.";
77 else
78 msg = "The following untracked working tree files would be %s by %s:\n%%s";
79 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("removed") + strlen(cmd2) - 4);
80 sprintf(tmp, msg, "removed", cmd, cmd2);
81 msgs[ERROR_WOULD_LOSE_UNTRACKED_REMOVED] = tmp;
82 tmp = xmalloc(strlen(msg) + strlen(cmd) + strlen("overwritten") + strlen(cmd2) - 4);
83 sprintf(tmp, msg, "overwritten", cmd, cmd2);
84 msgs[ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN] = tmp;
85
86 /*
87 * Special case: ERROR_BIND_OVERLAP refers to a pair of paths, we
88 * cannot easily display it as a list.
89 */
90 msgs[ERROR_BIND_OVERLAP] = "Entry '%s' overlaps with '%s'. Cannot bind.";
91
92 msgs[ERROR_SPARSE_NOT_UPTODATE_FILE] =
93 "Cannot update sparse checkout: the following entries are not up-to-date:\n%s";
94 msgs[ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN] =
95 "The following Working tree files would be overwritten by sparse checkout update:\n%s";
96 msgs[ERROR_WOULD_LOSE_ORPHANED_REMOVED] =
97 "The following Working tree files would be removed by sparse checkout update:\n%s";
98
99 opts->show_all_errors = 1;
100 /* rejected paths may not have a static buffer */
101 for (i = 0; i < ARRAY_SIZE(opts->unpack_rejects); i++)
102 opts->unpack_rejects[i].strdup_strings = 1;
103}
104
105static void do_add_entry(struct unpack_trees_options *o, struct cache_entry *ce,
106 unsigned int set, unsigned int clear)
107{
108 clear |= CE_HASHED | CE_UNHASHED;
109
110 if (set & CE_REMOVE)
111 set |= CE_WT_REMOVE;
112
113 ce->next = NULL;
114 ce->ce_flags = (ce->ce_flags & ~clear) | set;
115 add_index_entry(&o->result, ce,
116 ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
117}
118
119static struct cache_entry *dup_entry(const struct cache_entry *ce)
120{
121 unsigned int size = ce_size(ce);
122 struct cache_entry *new = xmalloc(size);
123
124 memcpy(new, ce, size);
125 return new;
126}
127
128static void add_entry(struct unpack_trees_options *o,
129 const struct cache_entry *ce,
130 unsigned int set, unsigned int clear)
131{
132 do_add_entry(o, dup_entry(ce), set, clear);
133}
134
135/*
136 * add error messages on path <path>
137 * corresponding to the type <e> with the message <msg>
138 * indicating if it should be display in porcelain or not
139 */
140static int add_rejected_path(struct unpack_trees_options *o,
141 enum unpack_trees_error_types e,
142 const char *path)
143{
144 if (!o->show_all_errors)
145 return error(ERRORMSG(o, e), path);
146
147 /*
148 * Otherwise, insert in a list for future display by
149 * display_error_msgs()
150 */
151 string_list_append(&o->unpack_rejects[e], path);
152 return -1;
153}
154
155/*
156 * display all the error messages stored in a nice way
157 */
158static void display_error_msgs(struct unpack_trees_options *o)
159{
160 int e, i;
161 int something_displayed = 0;
162 for (e = 0; e < NB_UNPACK_TREES_ERROR_TYPES; e++) {
163 struct string_list *rejects = &o->unpack_rejects[e];
164 if (rejects->nr > 0) {
165 struct strbuf path = STRBUF_INIT;
166 something_displayed = 1;
167 for (i = 0; i < rejects->nr; i++)
168 strbuf_addf(&path, "\t%s\n", rejects->items[i].string);
169 error(ERRORMSG(o, e), path.buf);
170 strbuf_release(&path);
171 }
172 string_list_clear(rejects, 0);
173 }
174 if (something_displayed)
175 fprintf(stderr, "Aborting\n");
176}
177
178/*
179 * Unlink the last component and schedule the leading directories for
180 * removal, such that empty directories get removed.
181 */
182static void unlink_entry(struct cache_entry *ce)
183{
184 if (!check_leading_path(ce->name, ce_namelen(ce)))
185 return;
186 if (remove_or_warn(ce->ce_mode, ce->name))
187 return;
188 schedule_dir_for_removal(ce->name, ce_namelen(ce));
189}
190
191static struct checkout state;
192static int check_updates(struct unpack_trees_options *o)
193{
194 unsigned cnt = 0, total = 0;
195 struct progress *progress = NULL;
196 struct index_state *index = &o->result;
197 int i;
198 int errs = 0;
199
200 if (o->update && o->verbose_update) {
201 for (total = cnt = 0; cnt < index->cache_nr; cnt++) {
202 struct cache_entry *ce = index->cache[cnt];
203 if (ce->ce_flags & (CE_UPDATE | CE_WT_REMOVE))
204 total++;
205 }
206
207 progress = start_progress_delay("Checking out files",
208 total, 50, 1);
209 cnt = 0;
210 }
211
212 if (o->update)
213 git_attr_set_direction(GIT_ATTR_CHECKOUT, &o->result);
214 for (i = 0; i < index->cache_nr; i++) {
215 struct cache_entry *ce = index->cache[i];
216
217 if (ce->ce_flags & CE_WT_REMOVE) {
218 display_progress(progress, ++cnt);
219 if (o->update && !o->dry_run)
220 unlink_entry(ce);
221 continue;
222 }
223 }
224 remove_marked_cache_entries(&o->result);
225 remove_scheduled_dirs();
226
227 for (i = 0; i < index->cache_nr; i++) {
228 struct cache_entry *ce = index->cache[i];
229
230 if (ce->ce_flags & CE_UPDATE) {
231 display_progress(progress, ++cnt);
232 ce->ce_flags &= ~CE_UPDATE;
233 if (o->update && !o->dry_run) {
234 errs |= checkout_entry(ce, &state, NULL);
235 }
236 }
237 }
238 stop_progress(&progress);
239 if (o->update)
240 git_attr_set_direction(GIT_ATTR_CHECKIN, NULL);
241 return errs != 0;
242}
243
244static int verify_uptodate_sparse(const struct cache_entry *ce,
245 struct unpack_trees_options *o);
246static int verify_absent_sparse(const struct cache_entry *ce,
247 enum unpack_trees_error_types,
248 struct unpack_trees_options *o);
249
250static int apply_sparse_checkout(struct cache_entry *ce, struct unpack_trees_options *o)
251{
252 int was_skip_worktree = ce_skip_worktree(ce);
253
254 if (ce->ce_flags & CE_NEW_SKIP_WORKTREE)
255 ce->ce_flags |= CE_SKIP_WORKTREE;
256 else
257 ce->ce_flags &= ~CE_SKIP_WORKTREE;
258
259 /*
260 * if (!was_skip_worktree && !ce_skip_worktree()) {
261 * This is perfectly normal. Move on;
262 * }
263 */
264
265 /*
266 * Merge strategies may set CE_UPDATE|CE_REMOVE outside checkout
267 * area as a result of ce_skip_worktree() shortcuts in
268 * verify_absent() and verify_uptodate().
269 * Make sure they don't modify worktree if they are already
270 * outside checkout area
271 */
272 if (was_skip_worktree && ce_skip_worktree(ce)) {
273 ce->ce_flags &= ~CE_UPDATE;
274
275 /*
276 * By default, when CE_REMOVE is on, CE_WT_REMOVE is also
277 * on to get that file removed from both index and worktree.
278 * If that file is already outside worktree area, don't
279 * bother remove it.
280 */
281 if (ce->ce_flags & CE_REMOVE)
282 ce->ce_flags &= ~CE_WT_REMOVE;
283 }
284
285 if (!was_skip_worktree && ce_skip_worktree(ce)) {
286 /*
287 * If CE_UPDATE is set, verify_uptodate() must be called already
288 * also stat info may have lost after merged_entry() so calling
289 * verify_uptodate() again may fail
290 */
291 if (!(ce->ce_flags & CE_UPDATE) && verify_uptodate_sparse(ce, o))
292 return -1;
293 ce->ce_flags |= CE_WT_REMOVE;
294 }
295 if (was_skip_worktree && !ce_skip_worktree(ce)) {
296 if (verify_absent_sparse(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o))
297 return -1;
298 ce->ce_flags |= CE_UPDATE;
299 }
300 return 0;
301}
302
303static inline int call_unpack_fn(const struct cache_entry * const *src,
304 struct unpack_trees_options *o)
305{
306 int ret = o->fn(src, o);
307 if (ret > 0)
308 ret = 0;
309 return ret;
310}
311
312static void mark_ce_used(struct cache_entry *ce, struct unpack_trees_options *o)
313{
314 ce->ce_flags |= CE_UNPACKED;
315
316 if (o->cache_bottom < o->src_index->cache_nr &&
317 o->src_index->cache[o->cache_bottom] == ce) {
318 int bottom = o->cache_bottom;
319 while (bottom < o->src_index->cache_nr &&
320 o->src_index->cache[bottom]->ce_flags & CE_UNPACKED)
321 bottom++;
322 o->cache_bottom = bottom;
323 }
324}
325
326static void mark_all_ce_unused(struct index_state *index)
327{
328 int i;
329 for (i = 0; i < index->cache_nr; i++)
330 index->cache[i]->ce_flags &= ~(CE_UNPACKED | CE_ADDED | CE_NEW_SKIP_WORKTREE);
331}
332
333static int locate_in_src_index(const struct cache_entry *ce,
334 struct unpack_trees_options *o)
335{
336 struct index_state *index = o->src_index;
337 int len = ce_namelen(ce);
338 int pos = index_name_pos(index, ce->name, len);
339 if (pos < 0)
340 pos = -1 - pos;
341 return pos;
342}
343
344/*
345 * We call unpack_index_entry() with an unmerged cache entry
346 * only in diff-index, and it wants a single callback. Skip
347 * the other unmerged entry with the same name.
348 */
349static void mark_ce_used_same_name(struct cache_entry *ce,
350 struct unpack_trees_options *o)
351{
352 struct index_state *index = o->src_index;
353 int len = ce_namelen(ce);
354 int pos;
355
356 for (pos = locate_in_src_index(ce, o); pos < index->cache_nr; pos++) {
357 struct cache_entry *next = index->cache[pos];
358 if (len != ce_namelen(next) ||
359 memcmp(ce->name, next->name, len))
360 break;
361 mark_ce_used(next, o);
362 }
363}
364
365static struct cache_entry *next_cache_entry(struct unpack_trees_options *o)
366{
367 const struct index_state *index = o->src_index;
368 int pos = o->cache_bottom;
369
370 while (pos < index->cache_nr) {
371 struct cache_entry *ce = index->cache[pos];
372 if (!(ce->ce_flags & CE_UNPACKED))
373 return ce;
374 pos++;
375 }
376 return NULL;
377}
378
379static void add_same_unmerged(struct cache_entry *ce,
380 struct unpack_trees_options *o)
381{
382 struct index_state *index = o->src_index;
383 int len = ce_namelen(ce);
384 int pos = index_name_pos(index, ce->name, len);
385
386 if (0 <= pos)
387 die("programming error in a caller of mark_ce_used_same_name");
388 for (pos = -pos - 1; pos < index->cache_nr; pos++) {
389 struct cache_entry *next = index->cache[pos];
390 if (len != ce_namelen(next) ||
391 memcmp(ce->name, next->name, len))
392 break;
393 add_entry(o, next, 0, 0);
394 mark_ce_used(next, o);
395 }
396}
397
398static int unpack_index_entry(struct cache_entry *ce,
399 struct unpack_trees_options *o)
400{
401 const struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
402 int ret;
403
404 src[0] = ce;
405
406 mark_ce_used(ce, o);
407 if (ce_stage(ce)) {
408 if (o->skip_unmerged) {
409 add_entry(o, ce, 0, 0);
410 return 0;
411 }
412 }
413 ret = call_unpack_fn(src, o);
414 if (ce_stage(ce))
415 mark_ce_used_same_name(ce, o);
416 return ret;
417}
418
419static int find_cache_pos(struct traverse_info *, const struct name_entry *);
420
421static void restore_cache_bottom(struct traverse_info *info, int bottom)
422{
423 struct unpack_trees_options *o = info->data;
424
425 if (o->diff_index_cached)
426 return;
427 o->cache_bottom = bottom;
428}
429
430static int switch_cache_bottom(struct traverse_info *info)
431{
432 struct unpack_trees_options *o = info->data;
433 int ret, pos;
434
435 if (o->diff_index_cached)
436 return 0;
437 ret = o->cache_bottom;
438 pos = find_cache_pos(info->prev, &info->name);
439
440 if (pos < -1)
441 o->cache_bottom = -2 - pos;
442 else if (pos < 0)
443 o->cache_bottom = o->src_index->cache_nr;
444 return ret;
445}
446
447static int traverse_trees_recursive(int n, unsigned long dirmask,
448 unsigned long df_conflicts,
449 struct name_entry *names,
450 struct traverse_info *info)
451{
452 int i, ret, bottom;
453 struct tree_desc t[MAX_UNPACK_TREES];
454 void *buf[MAX_UNPACK_TREES];
455 struct traverse_info newinfo;
456 struct name_entry *p;
457
458 p = names;
459 while (!p->mode)
460 p++;
461
462 newinfo = *info;
463 newinfo.prev = info;
464 newinfo.pathspec = info->pathspec;
465 newinfo.name = *p;
466 newinfo.pathlen += tree_entry_len(p) + 1;
467 newinfo.conflicts |= df_conflicts;
468
469 for (i = 0; i < n; i++, dirmask >>= 1) {
470 const unsigned char *sha1 = NULL;
471 if (dirmask & 1)
472 sha1 = names[i].sha1;
473 buf[i] = fill_tree_descriptor(t+i, sha1);
474 }
475
476 bottom = switch_cache_bottom(&newinfo);
477 ret = traverse_trees(n, t, &newinfo);
478 restore_cache_bottom(&newinfo, bottom);
479
480 for (i = 0; i < n; i++)
481 free(buf[i]);
482
483 return ret;
484}
485
486/*
487 * Compare the traverse-path to the cache entry without actually
488 * having to generate the textual representation of the traverse
489 * path.
490 *
491 * NOTE! This *only* compares up to the size of the traverse path
492 * itself - the caller needs to do the final check for the cache
493 * entry having more data at the end!
494 */
495static int do_compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
496{
497 int len, pathlen, ce_len;
498 const char *ce_name;
499
500 if (info->prev) {
501 int cmp = do_compare_entry(ce, info->prev, &info->name);
502 if (cmp)
503 return cmp;
504 }
505 pathlen = info->pathlen;
506 ce_len = ce_namelen(ce);
507
508 /* If ce_len < pathlen then we must have previously hit "name == directory" entry */
509 if (ce_len < pathlen)
510 return -1;
511
512 ce_len -= pathlen;
513 ce_name = ce->name + pathlen;
514
515 len = tree_entry_len(n);
516 return df_name_compare(ce_name, ce_len, S_IFREG, n->path, len, n->mode);
517}
518
519static int compare_entry(const struct cache_entry *ce, const struct traverse_info *info, const struct name_entry *n)
520{
521 int cmp = do_compare_entry(ce, info, n);
522 if (cmp)
523 return cmp;
524
525 /*
526 * Even if the beginning compared identically, the ce should
527 * compare as bigger than a directory leading up to it!
528 */
529 return ce_namelen(ce) > traverse_path_len(info, n);
530}
531
532static int ce_in_traverse_path(const struct cache_entry *ce,
533 const struct traverse_info *info)
534{
535 if (!info->prev)
536 return 1;
537 if (do_compare_entry(ce, info->prev, &info->name))
538 return 0;
539 /*
540 * If ce (blob) is the same name as the path (which is a tree
541 * we will be descending into), it won't be inside it.
542 */
543 return (info->pathlen < ce_namelen(ce));
544}
545
546static struct cache_entry *create_ce_entry(const struct traverse_info *info, const struct name_entry *n, int stage)
547{
548 int len = traverse_path_len(info, n);
549 struct cache_entry *ce = xcalloc(1, cache_entry_size(len));
550
551 ce->ce_mode = create_ce_mode(n->mode);
552 ce->ce_flags = create_ce_flags(stage);
553 ce->ce_namelen = len;
554 hashcpy(ce->sha1, n->sha1);
555 make_traverse_path(ce->name, info, n);
556
557 return ce;
558}
559
560static int unpack_nondirectories(int n, unsigned long mask,
561 unsigned long dirmask,
562 struct cache_entry **src,
563 const struct name_entry *names,
564 const struct traverse_info *info)
565{
566 int i;
567 struct unpack_trees_options *o = info->data;
568 unsigned long conflicts;
569
570 /* Do we have *only* directories? Nothing to do */
571 if (mask == dirmask && !src[0])
572 return 0;
573
574 conflicts = info->conflicts;
575 if (o->merge)
576 conflicts >>= 1;
577 conflicts |= dirmask;
578
579 /*
580 * Ok, we've filled in up to any potential index entry in src[0],
581 * now do the rest.
582 */
583 for (i = 0; i < n; i++) {
584 int stage;
585 unsigned int bit = 1ul << i;
586 if (conflicts & bit) {
587 src[i + o->merge] = o->df_conflict_entry;
588 continue;
589 }
590 if (!(mask & bit))
591 continue;
592 if (!o->merge)
593 stage = 0;
594 else if (i + 1 < o->head_idx)
595 stage = 1;
596 else if (i + 1 > o->head_idx)
597 stage = 3;
598 else
599 stage = 2;
600 src[i + o->merge] = create_ce_entry(info, names + i, stage);
601 }
602
603 if (o->merge)
604 return call_unpack_fn((const struct cache_entry * const *)src,
605 o);
606
607 for (i = 0; i < n; i++)
608 if (src[i] && src[i] != o->df_conflict_entry)
609 do_add_entry(o, src[i], 0, 0);
610 return 0;
611}
612
613static int unpack_failed(struct unpack_trees_options *o, const char *message)
614{
615 discard_index(&o->result);
616 if (!o->gently && !o->exiting_early) {
617 if (message)
618 return error("%s", message);
619 return -1;
620 }
621 return -1;
622}
623
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);
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
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;
663 continue;
664 }
665 if (!ce_in_traverse_path(ce, info))
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
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
740static int unpack_callback(int n, unsigned long mask, unsigned long dirmask, struct name_entry *names, struct traverse_info *info)
741{
742 struct cache_entry *src[MAX_UNPACK_TREES + 1] = { NULL, };
743 struct unpack_trees_options *o = info->data;
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
750 if (o->debug_unpack)
751 debug_unpack_callback(n, mask, dirmask, names, info);
752
753 /* Are we supposed to look at the index too? */
754 if (o->merge) {
755 while (1) {
756 int cmp;
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
764 if (!ce)
765 break;
766 cmp = compare_entry(ce, info, p);
767 if (cmp < 0) {
768 if (unpack_index_entry(ce, o) < 0)
769 return unpack_failed(o, NULL);
770 continue;
771 }
772 if (!cmp) {
773 if (ce_stage(ce)) {
774 /*
775 * If we skip unmerged index
776 * entries, we'll skip this
777 * entry *and* the tree
778 * entries associated with it!
779 */
780 if (o->skip_unmerged) {
781 add_same_unmerged(ce, o);
782 return mask;
783 }
784 }
785 src[0] = ce;
786 }
787 break;
788 }
789 }
790
791 if (unpack_nondirectories(n, mask, dirmask, src, names, info) < 0)
792 return -1;
793
794 if (o->merge && 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
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 }
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 /*
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.
821 */
822 if (matches) {
823 o->cache_bottom += matches;
824 return mask;
825 }
826 }
827
828 if (traverse_trees_recursive(n, dirmask, conflicts,
829 names, info) < 0)
830 return -1;
831 return mask;
832 }
833
834 return mask;
835}
836
837static int clear_ce_flags_1(struct cache_entry **cache, int nr,
838 char *prefix, int prefix_len,
839 int select_mask, int clear_mask,
840 struct exclude_list *el, int defval);
841
842/* Whole directory matching */
843static int clear_ce_flags_dir(struct cache_entry **cache, int nr,
844 char *prefix, int prefix_len,
845 char *basename,
846 int select_mask, int clear_mask,
847 struct exclude_list *el, int defval)
848{
849 struct cache_entry **cache_end;
850 int dtype = DT_DIR;
851 int ret = is_excluded_from_list(prefix, prefix_len,
852 basename, &dtype, el);
853
854 prefix[prefix_len++] = '/';
855
856 /* If undecided, use matching result of parent dir in defval */
857 if (ret < 0)
858 ret = defval;
859
860 for (cache_end = cache; cache_end != cache + nr; cache_end++) {
861 struct cache_entry *ce = *cache_end;
862 if (strncmp(ce->name, prefix, prefix_len))
863 break;
864 }
865
866 /*
867 * TODO: check el, if there are no patterns that may conflict
868 * with ret (iow, we know in advance the incl/excl
869 * decision for the entire directory), clear flag here without
870 * calling clear_ce_flags_1(). That function will call
871 * the expensive is_excluded_from_list() on every entry.
872 */
873 return clear_ce_flags_1(cache, cache_end - cache,
874 prefix, prefix_len,
875 select_mask, clear_mask,
876 el, ret);
877}
878
879/*
880 * Traverse the index, find every entry that matches according to
881 * o->el. Do "ce_flags &= ~clear_mask" on those entries. Return the
882 * number of traversed entries.
883 *
884 * If select_mask is non-zero, only entries whose ce_flags has on of
885 * those bits enabled are traversed.
886 *
887 * cache : pointer to an index entry
888 * prefix_len : an offset to its path
889 *
890 * The current path ("prefix") including the trailing '/' is
891 * cache[0]->name[0..(prefix_len-1)]
892 * Top level path has prefix_len zero.
893 */
894static int clear_ce_flags_1(struct cache_entry **cache, int nr,
895 char *prefix, int prefix_len,
896 int select_mask, int clear_mask,
897 struct exclude_list *el, int defval)
898{
899 struct cache_entry **cache_end = cache + nr;
900
901 /*
902 * Process all entries that have the given prefix and meet
903 * select_mask condition
904 */
905 while(cache != cache_end) {
906 struct cache_entry *ce = *cache;
907 const char *name, *slash;
908 int len, dtype, ret;
909
910 if (select_mask && !(ce->ce_flags & select_mask)) {
911 cache++;
912 continue;
913 }
914
915 if (prefix_len && strncmp(ce->name, prefix, prefix_len))
916 break;
917
918 name = ce->name + prefix_len;
919 slash = strchr(name, '/');
920
921 /* If it's a directory, try whole directory match first */
922 if (slash) {
923 int processed;
924
925 len = slash - name;
926 memcpy(prefix + prefix_len, name, len);
927
928 /*
929 * terminate the string (no trailing slash),
930 * clear_c_f_dir needs it
931 */
932 prefix[prefix_len + len] = '\0';
933 processed = clear_ce_flags_dir(cache, cache_end - cache,
934 prefix, prefix_len + len,
935 prefix + prefix_len,
936 select_mask, clear_mask,
937 el, defval);
938
939 /* clear_c_f_dir eats a whole dir already? */
940 if (processed) {
941 cache += processed;
942 continue;
943 }
944
945 prefix[prefix_len + len++] = '/';
946 cache += clear_ce_flags_1(cache, cache_end - cache,
947 prefix, prefix_len + len,
948 select_mask, clear_mask, el, defval);
949 continue;
950 }
951
952 /* Non-directory */
953 dtype = ce_to_dtype(ce);
954 ret = is_excluded_from_list(ce->name, ce_namelen(ce),
955 name, &dtype, el);
956 if (ret < 0)
957 ret = defval;
958 if (ret > 0)
959 ce->ce_flags &= ~clear_mask;
960 cache++;
961 }
962 return nr - (cache_end - cache);
963}
964
965static int clear_ce_flags(struct cache_entry **cache, int nr,
966 int select_mask, int clear_mask,
967 struct exclude_list *el)
968{
969 char prefix[PATH_MAX];
970 return clear_ce_flags_1(cache, nr,
971 prefix, 0,
972 select_mask, clear_mask,
973 el, 0);
974}
975
976/*
977 * Set/Clear CE_NEW_SKIP_WORKTREE according to $GIT_DIR/info/sparse-checkout
978 */
979static void mark_new_skip_worktree(struct exclude_list *el,
980 struct index_state *the_index,
981 int select_flag, int skip_wt_flag)
982{
983 int i;
984
985 /*
986 * 1. Pretend the narrowest worktree: only unmerged entries
987 * are checked out
988 */
989 for (i = 0; i < the_index->cache_nr; i++) {
990 struct cache_entry *ce = the_index->cache[i];
991
992 if (select_flag && !(ce->ce_flags & select_flag))
993 continue;
994
995 if (!ce_stage(ce))
996 ce->ce_flags |= skip_wt_flag;
997 else
998 ce->ce_flags &= ~skip_wt_flag;
999 }
1000
1001 /*
1002 * 2. Widen worktree according to sparse-checkout file.
1003 * Matched entries will have skip_wt_flag cleared (i.e. "in")
1004 */
1005 clear_ce_flags(the_index->cache, the_index->cache_nr,
1006 select_flag, skip_wt_flag, el);
1007}
1008
1009static int verify_absent(const struct cache_entry *,
1010 enum unpack_trees_error_types,
1011 struct unpack_trees_options *);
1012/*
1013 * N-way merge "len" trees. Returns 0 on success, -1 on failure to manipulate the
1014 * resulting index, -2 on failure to reflect the changes to the work tree.
1015 *
1016 * CE_ADDED, CE_UNPACKED and CE_NEW_SKIP_WORKTREE are used internally
1017 */
1018int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options *o)
1019{
1020 int i, ret;
1021 static struct cache_entry *dfc;
1022 struct exclude_list el;
1023
1024 if (len > MAX_UNPACK_TREES)
1025 die("unpack_trees takes at most %d trees", MAX_UNPACK_TREES);
1026 memset(&state, 0, sizeof(state));
1027 state.base_dir = "";
1028 state.force = 1;
1029 state.quiet = 1;
1030 state.refresh_cache = 1;
1031
1032 memset(&el, 0, sizeof(el));
1033 if (!core_apply_sparse_checkout || !o->update)
1034 o->skip_sparse_checkout = 1;
1035 if (!o->skip_sparse_checkout) {
1036 if (add_excludes_from_file_to_list(git_path("info/sparse-checkout"), "", 0, &el, 0) < 0)
1037 o->skip_sparse_checkout = 1;
1038 else
1039 o->el = ⪙
1040 }
1041
1042 memset(&o->result, 0, sizeof(o->result));
1043 o->result.initialized = 1;
1044 o->result.timestamp.sec = o->src_index->timestamp.sec;
1045 o->result.timestamp.nsec = o->src_index->timestamp.nsec;
1046 o->result.version = o->src_index->version;
1047 o->merge_size = len;
1048 mark_all_ce_unused(o->src_index);
1049
1050 /*
1051 * Sparse checkout loop #1: set NEW_SKIP_WORKTREE on existing entries
1052 */
1053 if (!o->skip_sparse_checkout)
1054 mark_new_skip_worktree(o->el, o->src_index, 0, CE_NEW_SKIP_WORKTREE);
1055
1056 if (!dfc)
1057 dfc = xcalloc(1, cache_entry_size(0));
1058 o->df_conflict_entry = dfc;
1059
1060 if (len) {
1061 const char *prefix = o->prefix ? o->prefix : "";
1062 struct traverse_info info;
1063
1064 setup_traverse_info(&info, prefix);
1065 info.fn = unpack_callback;
1066 info.data = o;
1067 info.show_all_errors = o->show_all_errors;
1068 info.pathspec = o->pathspec;
1069
1070 if (o->prefix) {
1071 /*
1072 * Unpack existing index entries that sort before the
1073 * prefix the tree is spliced into. Note that o->merge
1074 * is always true in this case.
1075 */
1076 while (1) {
1077 struct cache_entry *ce = next_cache_entry(o);
1078 if (!ce)
1079 break;
1080 if (ce_in_traverse_path(ce, &info))
1081 break;
1082 if (unpack_index_entry(ce, o) < 0)
1083 goto return_failed;
1084 }
1085 }
1086
1087 if (traverse_trees(len, t, &info) < 0)
1088 goto return_failed;
1089 }
1090
1091 /* Any left-over entries in the index? */
1092 if (o->merge) {
1093 while (1) {
1094 struct cache_entry *ce = next_cache_entry(o);
1095 if (!ce)
1096 break;
1097 if (unpack_index_entry(ce, o) < 0)
1098 goto return_failed;
1099 }
1100 }
1101 mark_all_ce_unused(o->src_index);
1102
1103 if (o->trivial_merges_only && o->nontrivial_merge) {
1104 ret = unpack_failed(o, "Merge requires file-level merging");
1105 goto done;
1106 }
1107
1108 if (!o->skip_sparse_checkout) {
1109 int empty_worktree = 1;
1110
1111 /*
1112 * Sparse checkout loop #2: set NEW_SKIP_WORKTREE on entries not in loop #1
1113 * If the will have NEW_SKIP_WORKTREE, also set CE_SKIP_WORKTREE
1114 * so apply_sparse_checkout() won't attempt to remove it from worktree
1115 */
1116 mark_new_skip_worktree(o->el, &o->result, CE_ADDED, CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1117
1118 ret = 0;
1119 for (i = 0; i < o->result.cache_nr; i++) {
1120 struct cache_entry *ce = o->result.cache[i];
1121
1122 /*
1123 * Entries marked with CE_ADDED in merged_entry() do not have
1124 * verify_absent() check (the check is effectively disabled
1125 * because CE_NEW_SKIP_WORKTREE is set unconditionally).
1126 *
1127 * Do the real check now because we have had
1128 * correct CE_NEW_SKIP_WORKTREE
1129 */
1130 if (ce->ce_flags & CE_ADDED &&
1131 verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1132 if (!o->show_all_errors)
1133 goto return_failed;
1134 ret = -1;
1135 }
1136
1137 if (apply_sparse_checkout(ce, o)) {
1138 if (!o->show_all_errors)
1139 goto return_failed;
1140 ret = -1;
1141 }
1142 if (!ce_skip_worktree(ce))
1143 empty_worktree = 0;
1144
1145 }
1146 if (ret < 0)
1147 goto return_failed;
1148 /*
1149 * Sparse checkout is meant to narrow down checkout area
1150 * but it does not make sense to narrow down to empty working
1151 * tree. This is usually a mistake in sparse checkout rules.
1152 * Do not allow users to do that.
1153 */
1154 if (o->result.cache_nr && empty_worktree) {
1155 ret = unpack_failed(o, "Sparse checkout leaves no entry on working directory");
1156 goto done;
1157 }
1158 }
1159
1160 o->src_index = NULL;
1161 ret = check_updates(o) ? (-2) : 0;
1162 if (o->dst_index)
1163 *o->dst_index = o->result;
1164
1165done:
1166 clear_exclude_list(&el);
1167 return ret;
1168
1169return_failed:
1170 if (o->show_all_errors)
1171 display_error_msgs(o);
1172 mark_all_ce_unused(o->src_index);
1173 ret = unpack_failed(o, NULL);
1174 if (o->exiting_early)
1175 ret = 0;
1176 goto done;
1177}
1178
1179/* Here come the merge functions */
1180
1181static int reject_merge(const struct cache_entry *ce,
1182 struct unpack_trees_options *o)
1183{
1184 return add_rejected_path(o, ERROR_WOULD_OVERWRITE, ce->name);
1185}
1186
1187static int same(const struct cache_entry *a, const struct cache_entry *b)
1188{
1189 if (!!a != !!b)
1190 return 0;
1191 if (!a && !b)
1192 return 1;
1193 if ((a->ce_flags | b->ce_flags) & CE_CONFLICTED)
1194 return 0;
1195 return a->ce_mode == b->ce_mode &&
1196 !hashcmp(a->sha1, b->sha1);
1197}
1198
1199
1200/*
1201 * When a CE gets turned into an unmerged entry, we
1202 * want it to be up-to-date
1203 */
1204static int verify_uptodate_1(const struct cache_entry *ce,
1205 struct unpack_trees_options *o,
1206 enum unpack_trees_error_types error_type)
1207{
1208 struct stat st;
1209
1210 if (o->index_only)
1211 return 0;
1212
1213 /*
1214 * CE_VALID and CE_SKIP_WORKTREE cheat, we better check again
1215 * if this entry is truly up-to-date because this file may be
1216 * overwritten.
1217 */
1218 if ((ce->ce_flags & CE_VALID) || ce_skip_worktree(ce))
1219 ; /* keep checking */
1220 else if (o->reset || ce_uptodate(ce))
1221 return 0;
1222
1223 if (!lstat(ce->name, &st)) {
1224 int flags = CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE;
1225 unsigned changed = ie_match_stat(o->src_index, ce, &st, flags);
1226 if (!changed)
1227 return 0;
1228 /*
1229 * NEEDSWORK: the current default policy is to allow
1230 * submodule to be out of sync wrt the superproject
1231 * index. This needs to be tightened later for
1232 * submodules that are marked to be automatically
1233 * checked out.
1234 */
1235 if (S_ISGITLINK(ce->ce_mode))
1236 return 0;
1237 errno = 0;
1238 }
1239 if (errno == ENOENT)
1240 return 0;
1241 return o->gently ? -1 :
1242 add_rejected_path(o, error_type, ce->name);
1243}
1244
1245static int verify_uptodate(const struct cache_entry *ce,
1246 struct unpack_trees_options *o)
1247{
1248 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1249 return 0;
1250 return verify_uptodate_1(ce, o, ERROR_NOT_UPTODATE_FILE);
1251}
1252
1253static int verify_uptodate_sparse(const struct cache_entry *ce,
1254 struct unpack_trees_options *o)
1255{
1256 return verify_uptodate_1(ce, o, ERROR_SPARSE_NOT_UPTODATE_FILE);
1257}
1258
1259static void invalidate_ce_path(const struct cache_entry *ce,
1260 struct unpack_trees_options *o)
1261{
1262 if (ce)
1263 cache_tree_invalidate_path(o->src_index->cache_tree, ce->name);
1264}
1265
1266/*
1267 * Check that checking out ce->sha1 in subdir ce->name is not
1268 * going to overwrite any working files.
1269 *
1270 * Currently, git does not checkout subprojects during a superproject
1271 * checkout, so it is not going to overwrite anything.
1272 */
1273static int verify_clean_submodule(const struct cache_entry *ce,
1274 enum unpack_trees_error_types error_type,
1275 struct unpack_trees_options *o)
1276{
1277 return 0;
1278}
1279
1280static int verify_clean_subdirectory(const struct cache_entry *ce,
1281 enum unpack_trees_error_types error_type,
1282 struct unpack_trees_options *o)
1283{
1284 /*
1285 * we are about to extract "ce->name"; we would not want to lose
1286 * anything in the existing directory there.
1287 */
1288 int namelen;
1289 int i;
1290 struct dir_struct d;
1291 char *pathbuf;
1292 int cnt = 0;
1293 unsigned char sha1[20];
1294
1295 if (S_ISGITLINK(ce->ce_mode) &&
1296 resolve_gitlink_ref(ce->name, "HEAD", sha1) == 0) {
1297 /* If we are not going to update the submodule, then
1298 * we don't care.
1299 */
1300 if (!hashcmp(sha1, ce->sha1))
1301 return 0;
1302 return verify_clean_submodule(ce, error_type, o);
1303 }
1304
1305 /*
1306 * First let's make sure we do not have a local modification
1307 * in that directory.
1308 */
1309 namelen = ce_namelen(ce);
1310 for (i = locate_in_src_index(ce, o);
1311 i < o->src_index->cache_nr;
1312 i++) {
1313 struct cache_entry *ce2 = o->src_index->cache[i];
1314 int len = ce_namelen(ce2);
1315 if (len < namelen ||
1316 strncmp(ce->name, ce2->name, namelen) ||
1317 ce2->name[namelen] != '/')
1318 break;
1319 /*
1320 * ce2->name is an entry in the subdirectory to be
1321 * removed.
1322 */
1323 if (!ce_stage(ce2)) {
1324 if (verify_uptodate(ce2, o))
1325 return -1;
1326 add_entry(o, ce2, CE_REMOVE, 0);
1327 mark_ce_used(ce2, o);
1328 }
1329 cnt++;
1330 }
1331
1332 /*
1333 * Then we need to make sure that we do not lose a locally
1334 * present file that is not ignored.
1335 */
1336 pathbuf = xmalloc(namelen + 2);
1337 memcpy(pathbuf, ce->name, namelen);
1338 strcpy(pathbuf+namelen, "/");
1339
1340 memset(&d, 0, sizeof(d));
1341 if (o->dir)
1342 d.exclude_per_dir = o->dir->exclude_per_dir;
1343 i = read_directory(&d, pathbuf, namelen+1, NULL);
1344 if (i)
1345 return o->gently ? -1 :
1346 add_rejected_path(o, ERROR_NOT_UPTODATE_DIR, ce->name);
1347 free(pathbuf);
1348 return cnt;
1349}
1350
1351/*
1352 * This gets called when there was no index entry for the tree entry 'dst',
1353 * but we found a file in the working tree that 'lstat()' said was fine,
1354 * and we're on a case-insensitive filesystem.
1355 *
1356 * See if we can find a case-insensitive match in the index that also
1357 * matches the stat information, and assume it's that other file!
1358 */
1359static int icase_exists(struct unpack_trees_options *o, const char *name, int len, struct stat *st)
1360{
1361 struct cache_entry *src;
1362
1363 src = index_name_exists(o->src_index, name, len, 1);
1364 return src && !ie_match_stat(o->src_index, src, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
1365}
1366
1367static int check_ok_to_remove(const char *name, int len, int dtype,
1368 const struct cache_entry *ce, struct stat *st,
1369 enum unpack_trees_error_types error_type,
1370 struct unpack_trees_options *o)
1371{
1372 struct cache_entry *result;
1373
1374 /*
1375 * It may be that the 'lstat()' succeeded even though
1376 * target 'ce' was absent, because there is an old
1377 * entry that is different only in case..
1378 *
1379 * Ignore that lstat() if it matches.
1380 */
1381 if (ignore_case && icase_exists(o, name, len, st))
1382 return 0;
1383
1384 if (o->dir &&
1385 is_excluded(o->dir, name, &dtype))
1386 /*
1387 * ce->name is explicitly excluded, so it is Ok to
1388 * overwrite it.
1389 */
1390 return 0;
1391 if (S_ISDIR(st->st_mode)) {
1392 /*
1393 * We are checking out path "foo" and
1394 * found "foo/." in the working tree.
1395 * This is tricky -- if we have modified
1396 * files that are in "foo/" we would lose
1397 * them.
1398 */
1399 if (verify_clean_subdirectory(ce, error_type, o) < 0)
1400 return -1;
1401 return 0;
1402 }
1403
1404 /*
1405 * The previous round may already have decided to
1406 * delete this path, which is in a subdirectory that
1407 * is being replaced with a blob.
1408 */
1409 result = index_name_exists(&o->result, name, len, 0);
1410 if (result) {
1411 if (result->ce_flags & CE_REMOVE)
1412 return 0;
1413 }
1414
1415 return o->gently ? -1 :
1416 add_rejected_path(o, error_type, name);
1417}
1418
1419/*
1420 * We do not want to remove or overwrite a working tree file that
1421 * is not tracked, unless it is ignored.
1422 */
1423static int verify_absent_1(const struct cache_entry *ce,
1424 enum unpack_trees_error_types error_type,
1425 struct unpack_trees_options *o)
1426{
1427 int len;
1428 struct stat st;
1429
1430 if (o->index_only || o->reset || !o->update)
1431 return 0;
1432
1433 len = check_leading_path(ce->name, ce_namelen(ce));
1434 if (!len)
1435 return 0;
1436 else if (len > 0) {
1437 char path[PATH_MAX + 1];
1438 memcpy(path, ce->name, len);
1439 path[len] = 0;
1440 if (lstat(path, &st))
1441 return error("cannot stat '%s': %s", path,
1442 strerror(errno));
1443
1444 return check_ok_to_remove(path, len, DT_UNKNOWN, NULL, &st,
1445 error_type, o);
1446 } else if (lstat(ce->name, &st)) {
1447 if (errno != ENOENT)
1448 return error("cannot stat '%s': %s", ce->name,
1449 strerror(errno));
1450 return 0;
1451 } else {
1452 return check_ok_to_remove(ce->name, ce_namelen(ce),
1453 ce_to_dtype(ce), ce, &st,
1454 error_type, o);
1455 }
1456}
1457
1458static int verify_absent(const struct cache_entry *ce,
1459 enum unpack_trees_error_types error_type,
1460 struct unpack_trees_options *o)
1461{
1462 if (!o->skip_sparse_checkout && (ce->ce_flags & CE_NEW_SKIP_WORKTREE))
1463 return 0;
1464 return verify_absent_1(ce, error_type, o);
1465}
1466
1467static int verify_absent_sparse(const struct cache_entry *ce,
1468 enum unpack_trees_error_types error_type,
1469 struct unpack_trees_options *o)
1470{
1471 enum unpack_trees_error_types orphaned_error = error_type;
1472 if (orphaned_error == ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN)
1473 orphaned_error = ERROR_WOULD_LOSE_ORPHANED_OVERWRITTEN;
1474
1475 return verify_absent_1(ce, orphaned_error, o);
1476}
1477
1478static int merged_entry(const struct cache_entry *ce,
1479 const struct cache_entry *old,
1480 struct unpack_trees_options *o)
1481{
1482 int update = CE_UPDATE;
1483 struct cache_entry *merge = dup_entry(ce);
1484
1485 if (!old) {
1486 /*
1487 * New index entries. In sparse checkout, the following
1488 * verify_absent() will be delayed until after
1489 * traverse_trees() finishes in unpack_trees(), then:
1490 *
1491 * - CE_NEW_SKIP_WORKTREE will be computed correctly
1492 * - verify_absent() be called again, this time with
1493 * correct CE_NEW_SKIP_WORKTREE
1494 *
1495 * verify_absent() call here does nothing in sparse
1496 * checkout (i.e. o->skip_sparse_checkout == 0)
1497 */
1498 update |= CE_ADDED;
1499 merge->ce_flags |= CE_NEW_SKIP_WORKTREE;
1500
1501 if (verify_absent(merge,
1502 ERROR_WOULD_LOSE_UNTRACKED_OVERWRITTEN, o)) {
1503 free(merge);
1504 return -1;
1505 }
1506 invalidate_ce_path(merge, o);
1507 } else if (!(old->ce_flags & CE_CONFLICTED)) {
1508 /*
1509 * See if we can re-use the old CE directly?
1510 * That way we get the uptodate stat info.
1511 *
1512 * This also removes the UPDATE flag on a match; otherwise
1513 * we will end up overwriting local changes in the work tree.
1514 */
1515 if (same(old, merge)) {
1516 copy_cache_entry(merge, old);
1517 update = 0;
1518 } else {
1519 if (verify_uptodate(old, o)) {
1520 free(merge);
1521 return -1;
1522 }
1523 /* Migrate old flags over */
1524 update |= old->ce_flags & (CE_SKIP_WORKTREE | CE_NEW_SKIP_WORKTREE);
1525 invalidate_ce_path(old, o);
1526 }
1527 } else {
1528 /*
1529 * Previously unmerged entry left as an existence
1530 * marker by read_index_unmerged();
1531 */
1532 invalidate_ce_path(old, o);
1533 }
1534
1535 do_add_entry(o, merge, update, CE_STAGEMASK);
1536 return 1;
1537}
1538
1539static int deleted_entry(const struct cache_entry *ce,
1540 const struct cache_entry *old,
1541 struct unpack_trees_options *o)
1542{
1543 /* Did it exist in the index? */
1544 if (!old) {
1545 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1546 return -1;
1547 return 0;
1548 }
1549 if (!(old->ce_flags & CE_CONFLICTED) && verify_uptodate(old, o))
1550 return -1;
1551 add_entry(o, ce, CE_REMOVE, 0);
1552 invalidate_ce_path(ce, o);
1553 return 1;
1554}
1555
1556static int keep_entry(const struct cache_entry *ce,
1557 struct unpack_trees_options *o)
1558{
1559 add_entry(o, ce, 0, 0);
1560 return 1;
1561}
1562
1563#if DBRT_DEBUG
1564static void show_stage_entry(FILE *o,
1565 const char *label, const struct cache_entry *ce)
1566{
1567 if (!ce)
1568 fprintf(o, "%s (missing)\n", label);
1569 else
1570 fprintf(o, "%s%06o %s %d\t%s\n",
1571 label,
1572 ce->ce_mode,
1573 sha1_to_hex(ce->sha1),
1574 ce_stage(ce),
1575 ce->name);
1576}
1577#endif
1578
1579int threeway_merge(const struct cache_entry * const *stages,
1580 struct unpack_trees_options *o)
1581{
1582 const struct cache_entry *index;
1583 const struct cache_entry *head;
1584 const struct cache_entry *remote = stages[o->head_idx + 1];
1585 int count;
1586 int head_match = 0;
1587 int remote_match = 0;
1588
1589 int df_conflict_head = 0;
1590 int df_conflict_remote = 0;
1591
1592 int any_anc_missing = 0;
1593 int no_anc_exists = 1;
1594 int i;
1595
1596 for (i = 1; i < o->head_idx; i++) {
1597 if (!stages[i] || stages[i] == o->df_conflict_entry)
1598 any_anc_missing = 1;
1599 else
1600 no_anc_exists = 0;
1601 }
1602
1603 index = stages[0];
1604 head = stages[o->head_idx];
1605
1606 if (head == o->df_conflict_entry) {
1607 df_conflict_head = 1;
1608 head = NULL;
1609 }
1610
1611 if (remote == o->df_conflict_entry) {
1612 df_conflict_remote = 1;
1613 remote = NULL;
1614 }
1615
1616 /*
1617 * First, if there's a #16 situation, note that to prevent #13
1618 * and #14.
1619 */
1620 if (!same(remote, head)) {
1621 for (i = 1; i < o->head_idx; i++) {
1622 if (same(stages[i], head)) {
1623 head_match = i;
1624 }
1625 if (same(stages[i], remote)) {
1626 remote_match = i;
1627 }
1628 }
1629 }
1630
1631 /*
1632 * We start with cases where the index is allowed to match
1633 * something other than the head: #14(ALT) and #2ALT, where it
1634 * is permitted to match the result instead.
1635 */
1636 /* #14, #14ALT, #2ALT */
1637 if (remote && !df_conflict_head && head_match && !remote_match) {
1638 if (index && !same(index, remote) && !same(index, head))
1639 return o->gently ? -1 : reject_merge(index, o);
1640 return merged_entry(remote, index, o);
1641 }
1642 /*
1643 * If we have an entry in the index cache, then we want to
1644 * make sure that it matches head.
1645 */
1646 if (index && !same(index, head))
1647 return o->gently ? -1 : reject_merge(index, o);
1648
1649 if (head) {
1650 /* #5ALT, #15 */
1651 if (same(head, remote))
1652 return merged_entry(head, index, o);
1653 /* #13, #3ALT */
1654 if (!df_conflict_remote && remote_match && !head_match)
1655 return merged_entry(head, index, o);
1656 }
1657
1658 /* #1 */
1659 if (!head && !remote && any_anc_missing)
1660 return 0;
1661
1662 /*
1663 * Under the "aggressive" rule, we resolve mostly trivial
1664 * cases that we historically had git-merge-one-file resolve.
1665 */
1666 if (o->aggressive) {
1667 int head_deleted = !head;
1668 int remote_deleted = !remote;
1669 const struct cache_entry *ce = NULL;
1670
1671 if (index)
1672 ce = index;
1673 else if (head)
1674 ce = head;
1675 else if (remote)
1676 ce = remote;
1677 else {
1678 for (i = 1; i < o->head_idx; i++) {
1679 if (stages[i] && stages[i] != o->df_conflict_entry) {
1680 ce = stages[i];
1681 break;
1682 }
1683 }
1684 }
1685
1686 /*
1687 * Deleted in both.
1688 * Deleted in one and unchanged in the other.
1689 */
1690 if ((head_deleted && remote_deleted) ||
1691 (head_deleted && remote && remote_match) ||
1692 (remote_deleted && head && head_match)) {
1693 if (index)
1694 return deleted_entry(index, index, o);
1695 if (ce && !head_deleted) {
1696 if (verify_absent(ce, ERROR_WOULD_LOSE_UNTRACKED_REMOVED, o))
1697 return -1;
1698 }
1699 return 0;
1700 }
1701 /*
1702 * Added in both, identically.
1703 */
1704 if (no_anc_exists && head && remote && same(head, remote))
1705 return merged_entry(head, index, o);
1706
1707 }
1708
1709 /* Below are "no merge" cases, which require that the index be
1710 * up-to-date to avoid the files getting overwritten with
1711 * conflict resolution files.
1712 */
1713 if (index) {
1714 if (verify_uptodate(index, o))
1715 return -1;
1716 }
1717
1718 o->nontrivial_merge = 1;
1719
1720 /* #2, #3, #4, #6, #7, #9, #10, #11. */
1721 count = 0;
1722 if (!head_match || !remote_match) {
1723 for (i = 1; i < o->head_idx; i++) {
1724 if (stages[i] && stages[i] != o->df_conflict_entry) {
1725 keep_entry(stages[i], o);
1726 count++;
1727 break;
1728 }
1729 }
1730 }
1731#if DBRT_DEBUG
1732 else {
1733 fprintf(stderr, "read-tree: warning #16 detected\n");
1734 show_stage_entry(stderr, "head ", stages[head_match]);
1735 show_stage_entry(stderr, "remote ", stages[remote_match]);
1736 }
1737#endif
1738 if (head) { count += keep_entry(head, o); }
1739 if (remote) { count += keep_entry(remote, o); }
1740 return count;
1741}
1742
1743/*
1744 * Two-way merge.
1745 *
1746 * The rule is to "carry forward" what is in the index without losing
1747 * information across a "fast-forward", favoring a successful merge
1748 * over a merge failure when it makes sense. For details of the
1749 * "carry forward" rule, please see <Documentation/git-read-tree.txt>.
1750 *
1751 */
1752int twoway_merge(const struct cache_entry * const *src,
1753 struct unpack_trees_options *o)
1754{
1755 const struct cache_entry *current = src[0];
1756 const struct cache_entry *oldtree = src[1];
1757 const struct cache_entry *newtree = src[2];
1758
1759 if (o->merge_size != 2)
1760 return error("Cannot do a twoway merge of %d trees",
1761 o->merge_size);
1762
1763 if (oldtree == o->df_conflict_entry)
1764 oldtree = NULL;
1765 if (newtree == o->df_conflict_entry)
1766 newtree = NULL;
1767
1768 if (current) {
1769 if ((!oldtree && !newtree) || /* 4 and 5 */
1770 (!oldtree && newtree &&
1771 same(current, newtree)) || /* 6 and 7 */
1772 (oldtree && newtree &&
1773 same(oldtree, newtree)) || /* 14 and 15 */
1774 (oldtree && newtree &&
1775 !same(oldtree, newtree) && /* 18 and 19 */
1776 same(current, newtree))) {
1777 return keep_entry(current, o);
1778 }
1779 else if (oldtree && !newtree && same(current, oldtree)) {
1780 /* 10 or 11 */
1781 return deleted_entry(oldtree, current, o);
1782 }
1783 else if (oldtree && newtree &&
1784 same(current, oldtree) && !same(current, newtree)) {
1785 /* 20 or 21 */
1786 return merged_entry(newtree, current, o);
1787 }
1788 else {
1789 /* all other failures */
1790 if (oldtree)
1791 return o->gently ? -1 : reject_merge(oldtree, o);
1792 if (current)
1793 return o->gently ? -1 : reject_merge(current, o);
1794 if (newtree)
1795 return o->gently ? -1 : reject_merge(newtree, o);
1796 return -1;
1797 }
1798 }
1799 else if (newtree) {
1800 if (oldtree && !o->initial_checkout) {
1801 /*
1802 * deletion of the path was staged;
1803 */
1804 if (same(oldtree, newtree))
1805 return 1;
1806 return reject_merge(oldtree, o);
1807 }
1808 return merged_entry(newtree, current, o);
1809 }
1810 return deleted_entry(oldtree, current, o);
1811}
1812
1813/*
1814 * Bind merge.
1815 *
1816 * Keep the index entries at stage0, collapse stage1 but make sure
1817 * stage0 does not have anything there.
1818 */
1819int bind_merge(const struct cache_entry * const *src,
1820 struct unpack_trees_options *o)
1821{
1822 const struct cache_entry *old = src[0];
1823 const struct cache_entry *a = src[1];
1824
1825 if (o->merge_size != 1)
1826 return error("Cannot do a bind merge of %d trees",
1827 o->merge_size);
1828 if (a && old)
1829 return o->gently ? -1 :
1830 error(ERRORMSG(o, ERROR_BIND_OVERLAP), a->name, old->name);
1831 if (!a)
1832 return keep_entry(old, o);
1833 else
1834 return merged_entry(a, NULL, o);
1835}
1836
1837/*
1838 * One-way merge.
1839 *
1840 * The rule is:
1841 * - take the stat information from stage0, take the data from stage1
1842 */
1843int oneway_merge(const struct cache_entry * const *src,
1844 struct unpack_trees_options *o)
1845{
1846 const struct cache_entry *old = src[0];
1847 const struct cache_entry *a = src[1];
1848
1849 if (o->merge_size != 1)
1850 return error("Cannot do a oneway merge of %d trees",
1851 o->merge_size);
1852
1853 if (!a || a == o->df_conflict_entry)
1854 return deleted_entry(old, old, o);
1855
1856 if (old && same(old, a)) {
1857 int update = 0;
1858 if (o->reset && o->update && !ce_uptodate(old) && !ce_skip_worktree(old)) {
1859 struct stat st;
1860 if (lstat(old->name, &st) ||
1861 ie_match_stat(o->src_index, old, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE))
1862 update |= CE_UPDATE;
1863 }
1864 add_entry(o, old, update, 0);
1865 return 0;
1866 }
1867 return merged_entry(a, old, o);
1868}