read-cache.c · leroysheep/LeeRoySheep

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1	/*
2	* GIT - The information manager from hell
3	*
4	* Copyright (C) Linus Torvalds, 2005
5	*/
6
7	#define USE_THE_REPOSITORY_VARIABLE
8	#define DISABLE_SIGN_COMPARE_WARNINGS
9
10	#include "git-compat-util.h"
11	#include "config.h"
12	#include "date.h"
13	#include "diff.h"
14	#include "diffcore.h"
15	#include "hex.h"
16	#include "tempfile.h"
17	#include "lockfile.h"
18	#include "cache-tree.h"
19	#include "refs.h"
20	#include "dir.h"
21	#include "object-file.h"
22	#include "odb.h"
23	#include "odb/transaction.h"
24	#include "oid-array.h"
25	#include "tree.h"
26	#include "commit.h"
27	#include "environment.h"
28	#include "gettext.h"
29	#include "mem-pool.h"
30	#include "name-hash.h"
31	#include "object-name.h"
32	#include "path.h"
33	#include "preload-index.h"
34	#include "read-cache.h"
35	#include "repository.h"
36	#include "resolve-undo.h"
37	#include "revision.h"
38	#include "strbuf.h"
39	#include "trace2.h"
40	#include "varint.h"
41	#include "split-index.h"
42	#include "symlinks.h"
43	#include "utf8.h"
44	#include "fsmonitor.h"
45	#include "thread-utils.h"
46	#include "progress.h"
47	#include "sparse-index.h"
48	#include "csum-file.h"
49	#include "promisor-remote.h"
50	#include "hook.h"
51	#include "submodule.h"
52	#include "submodule-config.h"
53	#include "advice.h"
54
55	/* Mask for the name length in ce_flags in the on-disk index */
56
57	#define CE_NAMEMASK (0x0fff)
58
59	/* Index extensions.
60	*
61	* The first letter should be 'A'..'Z' for extensions that are not
62	* necessary for a correct operation (i.e. optimization data).
63	* When new extensions are added that _needs_ to be understood in
64	* order to correctly interpret the index file, pick character that
65	* is outside the range, to cause the reader to abort.
66	*/
67
68	#define CACHE_EXT(s) ( (s[0]<<24)\|(s[1]<<16)\|(s[2]<<8)\|(s[3]) )
69	#define CACHE_EXT_TREE 0x54524545 /* "TREE" */
70	#define CACHE_EXT_RESOLVE_UNDO 0x52455543 /* "REUC" */
71	#define CACHE_EXT_LINK 0x6c696e6b /* "link" */
72	#define CACHE_EXT_UNTRACKED 0x554E5452 /* "UNTR" */
73	#define CACHE_EXT_FSMONITOR 0x46534D4E /* "FSMN" */
74	#define CACHE_EXT_ENDOFINDEXENTRIES 0x454F4945 /* "EOIE" */
75	#define CACHE_EXT_INDEXENTRYOFFSETTABLE 0x49454F54 /* "IEOT" */
76	#define CACHE_EXT_SPARSE_DIRECTORIES 0x73646972 /* "sdir" */
77
78	/* changes that can be kept in $GIT_DIR/index (basically all extensions) */
79	#define EXTMASK (RESOLVE_UNDO_CHANGED \| CACHE_TREE_CHANGED \| \
80	CE_ENTRY_ADDED \| CE_ENTRY_REMOVED \| CE_ENTRY_CHANGED \| \
81	SPLIT_INDEX_ORDERED \| UNTRACKED_CHANGED \| FSMONITOR_CHANGED)
82
83
84	/*
85	* This is an estimate of the pathname length in the index. We use
86	* this for V4 index files to guess the un-deltafied size of the index
87	* in memory because of pathname deltafication. This is not required
88	* for V2/V3 index formats because their pathnames are not compressed.
89	* If the initial amount of memory set aside is not sufficient, the
90	* mem pool will allocate extra memory.
91	*/
92	#define CACHE_ENTRY_PATH_LENGTH 80
93
94	enum index_search_mode {
95	NO_EXPAND_SPARSE = 0,
96	EXPAND_SPARSE = 1
97	};
98
99	static inline struct cache_entry mem_pool__ce_alloc(struct mem_pool mem_pool, size_t len)
100	{
101	struct cache_entry *ce;
102	ce = mem_pool_alloc(mem_pool, cache_entry_size(len));
103	ce->mem_pool_allocated = 1;
104	return ce;
105	}
106
107	static inline struct cache_entry mem_pool__ce_calloc(struct mem_pool mem_pool, size_t len)
108	{
109	struct cache_entry * ce;
110	ce = mem_pool_calloc(mem_pool, 1, cache_entry_size(len));
111	ce->mem_pool_allocated = 1;
112	return ce;
113	}
114
115	static struct mem_pool find_mem_pool(struct index_state istate)
116	{
117	struct mem_pool **pool_ptr;
118
119	if (istate->split_index && istate->split_index->base)
120	pool_ptr = &istate->split_index->base->ce_mem_pool;
121	else
122	pool_ptr = &istate->ce_mem_pool;
123
124	if (!*pool_ptr) {
125	pool_ptr = xmalloc(sizeof(*pool_ptr));
126	mem_pool_init(*pool_ptr, 0);
127	}
128
129	return *pool_ptr;
130	}
131
132	static const char *alternate_index_output;
133
134	static void set_index_entry(struct index_state istate, int nr, struct cache_entry ce)
135	{
136	if (S_ISSPARSEDIR(ce->ce_mode))
137	istate->sparse_index = INDEX_COLLAPSED;
138
139	istate->cache[nr] = ce;
140	add_name_hash(istate, ce);
141	}
142
143	static void replace_index_entry(struct index_state istate, int nr, struct cache_entry ce)
144	{
145	struct cache_entry *old = istate->cache[nr];
146
147	replace_index_entry_in_base(istate, old, ce);
148	remove_name_hash(istate, old);
149	discard_cache_entry(old);
150	ce->ce_flags &= ~CE_HASHED;
151	set_index_entry(istate, nr, ce);
152	ce->ce_flags \|= CE_UPDATE_IN_BASE;
153	mark_fsmonitor_invalid(istate, ce);
154	istate->cache_changed \|= CE_ENTRY_CHANGED;
155	}
156
157	void rename_index_entry_at(struct index_state istate, int nr, const char new_name)
158	{
159	struct cache_entry old_entry = istate->cache[nr], new_entry, *refreshed;
160	int namelen = strlen(new_name);
161
162	new_entry = make_empty_cache_entry(istate, namelen);
163	copy_cache_entry(new_entry, old_entry);
164	new_entry->ce_flags &= ~CE_HASHED;
165	new_entry->ce_namelen = namelen;
166	new_entry->index = 0;
167	memcpy(new_entry->name, new_name, namelen + 1);
168
169	cache_tree_invalidate_path(istate, old_entry->name);
170	untracked_cache_remove_from_index(istate, old_entry->name);
171	remove_index_entry_at(istate, nr);
172
173	/*
174	* Refresh the new index entry. Using 'refresh_cache_entry' ensures
175	* we only update stat info if the entry is otherwise up-to-date (i.e.,
176	* the contents/mode haven't changed). This ensures that we reflect the
177	* 'ctime' of the rename in the index without (incorrectly) updating
178	* the cached stat info to reflect unstaged changes on disk.
179	*/
180	refreshed = refresh_cache_entry(istate, new_entry, CE_MATCH_REFRESH);
181	if (refreshed && refreshed != new_entry) {
182	add_index_entry(istate, refreshed, ADD_CACHE_OK_TO_ADD\|ADD_CACHE_OK_TO_REPLACE);
183	discard_cache_entry(new_entry);
184	} else
185	add_index_entry(istate, new_entry, ADD_CACHE_OK_TO_ADD\|ADD_CACHE_OK_TO_REPLACE);
186	}
187
188	/*
189	* This only updates the "non-critical" parts of the directory
190	* cache, ie the parts that aren't tracked by GIT, and only used
191	* to validate the cache.
192	*/
193	void fill_stat_cache_info(struct index_state istate, struct cache_entry ce, struct stat *st)
194	{
195	fill_stat_data(&ce->ce_stat_data, st);
196
197	if (assume_unchanged)
198	ce->ce_flags \|= CE_VALID;
199
200	if (S_ISREG(st->st_mode)) {
201	ce_mark_uptodate(ce);
202	mark_fsmonitor_valid(istate, ce);
203	}
204	}
205
206	static unsigned int st_mode_from_ce(const struct cache_entry *ce)
207	{
208	extern int trust_executable_bit, has_symlinks;
209
210	switch (ce->ce_mode & S_IFMT) {
211	case S_IFLNK:
212	return has_symlinks ? S_IFLNK : (S_IFREG \| 0644);
213	case S_IFREG:
214	return (ce->ce_mode & (trust_executable_bit ? 0755 : 0644)) \| S_IFREG;
215	case S_IFGITLINK:
216	return S_IFDIR \| 0755;
217	case S_IFDIR:
218	return ce->ce_mode;
219	default:
220	BUG("unsupported ce_mode: %o", ce->ce_mode);
221	}
222	}
223
224	int fake_lstat(const struct cache_entry ce, struct stat st)
225	{
226	fake_lstat_data(&ce->ce_stat_data, st);
227	st->st_mode = st_mode_from_ce(ce);
228
229	/* always succeed as lstat() replacement */
230	return 0;
231	}
232
233	static int ce_compare_data(struct index_state *istate,
234	const struct cache_entry *ce,
235	struct stat *st)
236	{
237	int match = -1;
238	int fd = git_open_cloexec(ce->name, O_RDONLY);
239
240	if (fd >= 0) {
241	struct object_id oid;
242	if (!index_fd(istate, &oid, fd, st, OBJ_BLOB, ce->name, 0))
243	match = !oideq(&oid, &ce->oid);
244	/* index_fd() closed the file descriptor already */
245	}
246	return match;
247	}
248
249	static int ce_compare_link(const struct cache_entry *ce, size_t expected_size)
250	{
251	int match = -1;
252	void *buffer;
253	unsigned long size;
254	enum object_type type;
255	struct strbuf sb = STRBUF_INIT;
256
257	if (strbuf_readlink(&sb, ce->name, expected_size))
258	return -1;
259
260	buffer = odb_read_object(the_repository->objects, &ce->oid, &type, &size);
261	if (buffer) {
262	if (size == sb.len)
263	match = memcmp(buffer, sb.buf, size);
264	free(buffer);
265	}
266	strbuf_release(&sb);
267	return match;
268	}
269
270	static int ce_compare_gitlink(const struct cache_entry *ce)
271	{
272	struct object_id oid;
273
274	/*
275	* We don't actually require that the .git directory
276	* under GITLINK directory be a valid git directory. It
277	* might even be missing (in case nobody populated that
278	* sub-project).
279	*
280	* If so, we consider it always to match.
281	*/
282	if (repo_resolve_gitlink_ref(the_repository, ce->name,
283	"HEAD", &oid) < 0)
284	return 0;
285	return !oideq(&oid, &ce->oid);
286	}
287
288	static int ce_modified_check_fs(struct index_state *istate,
289	const struct cache_entry *ce,
290	struct stat *st)
291	{
292	switch (st->st_mode & S_IFMT) {
293	case S_IFREG:
294	if (ce_compare_data(istate, ce, st))
295	return DATA_CHANGED;
296	break;
297	case S_IFLNK:
298	if (ce_compare_link(ce, xsize_t(st->st_size)))
299	return DATA_CHANGED;
300	break;
301	case S_IFDIR:
302	if (S_ISGITLINK(ce->ce_mode))
303	return ce_compare_gitlink(ce) ? DATA_CHANGED : 0;
304	/* else fallthrough */
305	default:
306	return TYPE_CHANGED;
307	}
308	return 0;
309	}
310
311	static int ce_match_stat_basic(const struct cache_entry ce, struct stat st)
312	{
313	unsigned int changed = 0;
314
315	if (ce->ce_flags & CE_REMOVE)
316	return MODE_CHANGED \| DATA_CHANGED \| TYPE_CHANGED;
317
318	switch (ce->ce_mode & S_IFMT) {
319	case S_IFREG:
320	changed \|= !S_ISREG(st->st_mode) ? TYPE_CHANGED : 0;
321	/* We consider only the owner x bit to be relevant for
322	* "mode changes"
323	*/
324	if (trust_executable_bit &&
325	(0100 & (ce->ce_mode ^ st->st_mode)))
326	changed \|= MODE_CHANGED;
327	break;
328	case S_IFLNK:
329	if (!S_ISLNK(st->st_mode) &&
330	(has_symlinks \|\| !S_ISREG(st->st_mode)))
331	changed \|= TYPE_CHANGED;
332	break;
333	case S_IFGITLINK:
334	/* We ignore most of the st_xxx fields for gitlinks */
335	if (!S_ISDIR(st->st_mode))
336	changed \|= TYPE_CHANGED;
337	else if (ce_compare_gitlink(ce))
338	changed \|= DATA_CHANGED;
339	return changed;
340	default:
341	BUG("unsupported ce_mode: %o", ce->ce_mode);
342	}
343
344	changed \|= match_stat_data(&ce->ce_stat_data, st);
345
346	/* Racily smudged entry? */
347	if (!ce->ce_stat_data.sd_size) {
348	if (!is_empty_blob_oid(&ce->oid, the_repository->hash_algo))
349	changed \|= DATA_CHANGED;
350	}
351
352	return changed;
353	}
354
355	static int is_racy_stat(const struct index_state *istate,
356	const struct stat_data *sd)
357	{
358	return (istate->timestamp.sec &&
359	#ifdef USE_NSEC
360	/* nanosecond timestamped files can also be racy! */
361	(istate->timestamp.sec < sd->sd_mtime.sec \|\|
362	(istate->timestamp.sec == sd->sd_mtime.sec &&
363	istate->timestamp.nsec <= sd->sd_mtime.nsec))
364	#else
365	istate->timestamp.sec <= sd->sd_mtime.sec
366	#endif
367	);
368	}
369
370	int is_racy_timestamp(const struct index_state *istate,
371	const struct cache_entry *ce)
372	{
373	return (!S_ISGITLINK(ce->ce_mode) &&
374	is_racy_stat(istate, &ce->ce_stat_data));
375	}
376
377	int match_stat_data_racy(const struct index_state *istate,
378	const struct stat_data sd, struct stat st)
379	{
380	if (is_racy_stat(istate, sd))
381	return MTIME_CHANGED;
382	return match_stat_data(sd, st);
383	}
384
385	int ie_match_stat(struct index_state *istate,
386	const struct cache_entry ce, struct stat st,
387	unsigned int options)
388	{
389	unsigned int changed;
390	int ignore_valid = options & CE_MATCH_IGNORE_VALID;
391	int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
392	int assume_racy_is_modified = options & CE_MATCH_RACY_IS_DIRTY;
393	int ignore_fsmonitor = options & CE_MATCH_IGNORE_FSMONITOR;
394
395	if (!ignore_fsmonitor)
396	refresh_fsmonitor(istate);
397	/*
398	* If it's marked as always valid in the index, it's
399	* valid whatever the checked-out copy says.
400	*
401	* skip-worktree has the same effect with higher precedence
402	*/
403	if (!ignore_skip_worktree && ce_skip_worktree(ce))
404	return 0;
405	if (!ignore_valid && (ce->ce_flags & CE_VALID))
406	return 0;
407	if (!ignore_fsmonitor && (ce->ce_flags & CE_FSMONITOR_VALID))
408	return 0;
409
410	/*
411	* Intent-to-add entries have not been added, so the index entry
412	* by definition never matches what is in the work tree until it
413	* actually gets added.
414	*/
415	if (ce_intent_to_add(ce))
416	return DATA_CHANGED \| TYPE_CHANGED \| MODE_CHANGED;
417
418	changed = ce_match_stat_basic(ce, st);
419
420	/*
421	* Within 1 second of this sequence:
422	* echo xyzzy >file && git-update-index --add file
423	* running this command:
424	* echo frotz >file
425	* would give a falsely clean cache entry. The mtime and
426	* length match the cache, and other stat fields do not change.
427	*
428	* We could detect this at update-index time (the cache entry
429	* being registered/updated records the same time as "now")
430	* and delay the return from git-update-index, but that would
431	* effectively mean we can make at most one commit per second,
432	* which is not acceptable. Instead, we check cache entries
433	* whose mtime are the same as the index file timestamp more
434	* carefully than others.
435	*/
436	if (!changed && is_racy_timestamp(istate, ce)) {
437	if (assume_racy_is_modified)
438	changed \|= DATA_CHANGED;
439	else
440	changed \|= ce_modified_check_fs(istate, ce, st);
441	}
442
443	return changed;
444	}
445
446	int ie_modified(struct index_state *istate,
447	const struct cache_entry *ce,
448	struct stat *st, unsigned int options)
449	{
450	int changed, changed_fs;
451
452	changed = ie_match_stat(istate, ce, st, options);
453	if (!changed)
454	return 0;
455	/*
456	* If the mode or type has changed, there's no point in trying
457	* to refresh the entry - it's not going to match
458	*/
459	if (changed & (MODE_CHANGED \| TYPE_CHANGED))
460	return changed;
461
462	/*
463	* Immediately after read-tree or update-index --cacheinfo,
464	* the length field is zero, as we have never even read the
465	* lstat(2) information once, and we cannot trust DATA_CHANGED
466	* returned by ie_match_stat() which in turn was returned by
467	* ce_match_stat_basic() to signal that the filesize of the
468	* blob changed. We have to actually go to the filesystem to
469	* see if the contents match, and if so, should answer "unchanged".
470	*
471	* The logic does not apply to gitlinks, as ce_match_stat_basic()
472	* already has checked the actual HEAD from the filesystem in the
473	* subproject. If ie_match_stat() already said it is different,
474	* then we know it is.
475	*/
476	if ((changed & DATA_CHANGED) &&
477	#ifdef GIT_WINDOWS_NATIVE
478	/*
479	* Work around Git for Windows v2.27.0 fixing a bug where symlinks'
480	* target path lengths were not read at all, and instead recorded
481	* as 4096: now, all symlinks would appear as modified.
482	*
483	* So let's just special-case symlinks with a target path length
484	* (i.e. `sd_size`) of 4096 and force them to be re-checked.
485	*/
486	(!S_ISLNK(st->st_mode) \|\| ce->ce_stat_data.sd_size != MAX_PATH) &&
487	#endif
488	(S_ISGITLINK(ce->ce_mode) \|\| ce->ce_stat_data.sd_size != 0))
489	return changed;
490
491	changed_fs = ce_modified_check_fs(istate, ce, st);
492	if (changed_fs)
493	return changed \| changed_fs;
494	return 0;
495	}
496
497	static int cache_name_stage_compare(const char *name1, int len1, int stage1,
498	const char *name2, int len2, int stage2)
499	{
500	int cmp;
501
502	cmp = name_compare(name1, len1, name2, len2);
503	if (cmp)
504	return cmp;
505
506	if (stage1 < stage2)
507	return -1;
508	if (stage1 > stage2)
509	return 1;
510	return 0;
511	}
512
513	int cmp_cache_name_compare(const void a_, const void b_)
514	{
515	const struct cache_entry ce1, ce2;
516
517	ce1 = ((const struct cache_entry *)a_);
518	ce2 = ((const struct cache_entry *)b_);
519	return cache_name_stage_compare(ce1->name, ce1->ce_namelen, ce_stage(ce1),
520	ce2->name, ce2->ce_namelen, ce_stage(ce2));
521	}
522
523	static int index_name_stage_pos(struct index_state *istate,
524	const char *name, int namelen,
525	int stage,
526	enum index_search_mode search_mode)
527	{
528	int first, last;
529
530	first = 0;
531	last = istate->cache_nr;
532	while (last > first) {
533	int next = first + ((last - first) >> 1);
534	struct cache_entry *ce = istate->cache[next];
535	int cmp = cache_name_stage_compare(name, namelen, stage, ce->name, ce_namelen(ce), ce_stage(ce));
536	if (!cmp)
537	return next;
538	if (cmp < 0) {
539	last = next;
540	continue;
541	}
542	first = next+1;
543	}
544
545	if (search_mode == EXPAND_SPARSE && istate->sparse_index &&
546	first > 0) {
547	/* Note: first <= istate->cache_nr */
548	struct cache_entry *ce = istate->cache[first - 1];
549
550	/*
551	* If we are in a sparse-index _and_ the entry before the
552	* insertion position is a sparse-directory entry that is
553	* an ancestor of 'name', then we need to expand the index
554	* and search again. This will only trigger once, because
555	* thereafter the index is fully expanded.
556	*/
557	if (S_ISSPARSEDIR(ce->ce_mode) &&
558	ce_namelen(ce) < namelen &&
559	!strncmp(name, ce->name, ce_namelen(ce))) {
560	ensure_full_index(istate);
561	return index_name_stage_pos(istate, name, namelen, stage, search_mode);
562	}
563	}
564
565	return -first-1;
566	}
567
568	int index_name_pos(struct index_state istate, const char name, int namelen)
569	{
570	return index_name_stage_pos(istate, name, namelen, 0, EXPAND_SPARSE);
571	}
572
573	int index_name_pos_sparse(struct index_state istate, const char name, int namelen)
574	{
575	return index_name_stage_pos(istate, name, namelen, 0, NO_EXPAND_SPARSE);
576	}
577
578	int index_entry_exists(struct index_state istate, const char name, int namelen)
579	{
580	return index_name_stage_pos(istate, name, namelen, 0, NO_EXPAND_SPARSE) >= 0;
581	}
582
583	int remove_index_entry_at(struct index_state *istate, int pos)
584	{
585	struct cache_entry *ce = istate->cache[pos];
586
587	record_resolve_undo(istate, ce);
588	remove_name_hash(istate, ce);
589	save_or_free_index_entry(istate, ce);
590	istate->cache_changed \|= CE_ENTRY_REMOVED;
591	istate->cache_nr--;
592	if (pos >= istate->cache_nr)
593	return 0;
594	MOVE_ARRAY(istate->cache + pos, istate->cache + pos + 1,
595	istate->cache_nr - pos);
596	return 1;
597	}
598
599	/*
600	* Remove all cache entries marked for removal, that is where
601	* CE_REMOVE is set in ce_flags. This is much more effective than
602	* calling remove_index_entry_at() for each entry to be removed.
603	*/
604	void remove_marked_cache_entries(struct index_state *istate, int invalidate)
605	{
606	struct cache_entry **ce_array = istate->cache;
607	unsigned int i, j;
608
609	for (i = j = 0; i < istate->cache_nr; i++) {
610	if (ce_array[i]->ce_flags & CE_REMOVE) {
611	if (invalidate) {
612	cache_tree_invalidate_path(istate,
613	ce_array[i]->name);
614	untracked_cache_remove_from_index(istate,
615	ce_array[i]->name);
616	}
617	remove_name_hash(istate, ce_array[i]);
618	save_or_free_index_entry(istate, ce_array[i]);
619	}
620	else
621	ce_array[j++] = ce_array[i];
622	}
623	if (j == istate->cache_nr)
624	return;
625	istate->cache_changed \|= CE_ENTRY_REMOVED;
626	istate->cache_nr = j;
627	}
628
629	int remove_file_from_index(struct index_state istate, const char path)
630	{
631	int pos = index_name_pos(istate, path, strlen(path));
632	if (pos < 0)
633	pos = -pos-1;
634	cache_tree_invalidate_path(istate, path);
635	untracked_cache_remove_from_index(istate, path);
636	while (pos < istate->cache_nr && !strcmp(istate->cache[pos]->name, path))
637	remove_index_entry_at(istate, pos);
638	return 0;
639	}
640
641	static int compare_name(struct cache_entry ce, const char path, int namelen)
642	{
643	return namelen != ce_namelen(ce) \|\| memcmp(path, ce->name, namelen);
644	}
645
646	static int index_name_pos_also_unmerged(struct index_state *istate,
647	const char *path, int namelen)
648	{
649	int pos = index_name_pos(istate, path, namelen);
650	struct cache_entry *ce;
651
652	if (pos >= 0)
653	return pos;
654
655	/* maybe unmerged? */
656	pos = -1 - pos;
657	if (pos >= istate->cache_nr \|\|
658	compare_name((ce = istate->cache[pos]), path, namelen))
659	return -1;
660
661	/* order of preference: stage 2, 1, 3 */
662	if (ce_stage(ce) == 1 && pos + 1 < istate->cache_nr &&
663	ce_stage((ce = istate->cache[pos + 1])) == 2 &&
664	!compare_name(ce, path, namelen))
665	pos++;
666	return pos;
667	}
668
669	static int different_name(struct cache_entry ce, struct cache_entry alias)
670	{
671	int len = ce_namelen(ce);
672	return ce_namelen(alias) != len \|\| memcmp(ce->name, alias->name, len);
673	}
674
675	/*
676	* If we add a filename that aliases in the cache, we will use the
677	* name that we already have - but we don't want to update the same
678	* alias twice, because that implies that there were actually two
679	* different files with aliasing names!
680	*
681	* So we use the CE_ADDED flag to verify that the alias was an old
682	* one before we accept it as
683	*/
684	static struct cache_entry create_alias_ce(struct index_state istate,
685	struct cache_entry *ce,
686	struct cache_entry *alias)
687	{
688	int len;
689	struct cache_entry *new_entry;
690
691	if (alias->ce_flags & CE_ADDED)
692	die(_("will not add file alias '%s' ('%s' already exists in index)"),
693	ce->name, alias->name);
694
695	/* Ok, create the new entry using the name of the existing alias */
696	len = ce_namelen(alias);
697	new_entry = make_empty_cache_entry(istate, len);
698	memcpy(new_entry->name, alias->name, len);
699	copy_cache_entry(new_entry, ce);
700	save_or_free_index_entry(istate, ce);
701	return new_entry;
702	}
703
704	void set_object_name_for_intent_to_add_entry(struct cache_entry *ce)
705	{
706	struct object_id oid;
707	if (odb_write_object(the_repository->objects, "", 0, OBJ_BLOB, &oid))
708	die(_("cannot create an empty blob in the object database"));
709	oidcpy(&ce->oid, &oid);
710	}
711
712	int add_to_index(struct index_state istate, const char path, struct stat *st, int flags)
713	{
714	int namelen, was_same;
715	mode_t st_mode = st->st_mode;
716	struct cache_entry ce, alias = NULL;
717	unsigned ce_option = CE_MATCH_IGNORE_VALID\|CE_MATCH_IGNORE_SKIP_WORKTREE\|CE_MATCH_RACY_IS_DIRTY;
718	int verbose = flags & (ADD_CACHE_VERBOSE \| ADD_CACHE_PRETEND);
719	int pretend = flags & ADD_CACHE_PRETEND;
720	int intent_only = flags & ADD_CACHE_INTENT;
721	int add_option = (ADD_CACHE_OK_TO_ADD\|ADD_CACHE_OK_TO_REPLACE\|
722	(intent_only ? ADD_CACHE_NEW_ONLY : 0));
723	unsigned hash_flags = pretend ? 0 : INDEX_WRITE_OBJECT;
724
725	if (flags & ADD_CACHE_RENORMALIZE)
726	hash_flags \|= INDEX_RENORMALIZE;
727
728	if (!S_ISREG(st_mode) && !S_ISLNK(st_mode) && !S_ISDIR(st_mode))
729	return error(_("%s: can only add regular files, symbolic links or git-directories"), path);
730
731	namelen = strlen(path);
732	if (S_ISDIR(st_mode)) {
733	while (namelen && path[namelen-1] == '/')
734	namelen--;
735	}
736	ce = make_empty_cache_entry(istate, namelen);
737	memcpy(ce->name, path, namelen);
738	ce->ce_namelen = namelen;
739	if (!intent_only)
740	fill_stat_cache_info(istate, ce, st);
741	else
742	ce->ce_flags \|= CE_INTENT_TO_ADD;
743
744
745	if (trust_executable_bit && has_symlinks) {
746	ce->ce_mode = create_ce_mode(st_mode);
747	} else {
748	/* If there is an existing entry, pick the mode bits and type
749	* from it, otherwise assume unexecutable regular file.
750	*/
751	struct cache_entry *ent;
752	int pos = index_name_pos_also_unmerged(istate, path, namelen);
753
754	ent = (0 <= pos) ? istate->cache[pos] : NULL;
755	ce->ce_mode = ce_mode_from_stat(ent, st_mode);
756	}
757
758	/* When core.ignorecase=true, determine if a directory of the same name but differing
759	* case already exists within the Git repository. If it does, ensure the directory
760	* case of the file being added to the repository matches (is folded into) the existing
761	* entry's directory case.
762	*/
763	if (ignore_case) {
764	adjust_dirname_case(istate, ce->name);
765	}
766	if (!(flags & ADD_CACHE_RENORMALIZE)) {
767	alias = index_file_exists(istate, ce->name,
768	ce_namelen(ce), ignore_case);
769	if (alias &&
770	!ce_stage(alias) &&
771	!ie_match_stat(istate, alias, st, ce_option)) {
772	/* Nothing changed, really */
773	if (!S_ISGITLINK(alias->ce_mode))
774	ce_mark_uptodate(alias);
775	alias->ce_flags \|= CE_ADDED;
776
777	discard_cache_entry(ce);
778	return 0;
779	}
780	}
781	if (!intent_only) {
782	if (index_path(istate, &ce->oid, path, st, hash_flags)) {
783	discard_cache_entry(ce);
784	return error(_("unable to index file '%s'"), path);
785	}
786	} else
787	set_object_name_for_intent_to_add_entry(ce);
788
789	if (ignore_case && alias && different_name(ce, alias))
790	ce = create_alias_ce(istate, ce, alias);
791	ce->ce_flags \|= CE_ADDED;
792
793	/* It was suspected to be racily clean, but it turns out to be Ok */
794	was_same = (alias &&
795	!ce_stage(alias) &&
796	oideq(&alias->oid, &ce->oid) &&
797	ce->ce_mode == alias->ce_mode);
798
799	if (pretend)
800	discard_cache_entry(ce);
801	else if (add_index_entry(istate, ce, add_option)) {
802	discard_cache_entry(ce);
803	return error(_("unable to add '%s' to index"), path);
804	}
805	if (verbose && !was_same)
806	printf("add '%s'\n", path);
807	return 0;
808	}
809
810	int add_file_to_index(struct index_state istate, const char path, int flags)
811	{
812	struct stat st;
813	if (lstat(path, &st))
814	die_errno(_("unable to stat '%s'"), path);
815	return add_to_index(istate, path, &st, flags);
816	}
817
818	struct cache_entry make_empty_cache_entry(struct index_state istate, size_t len)
819	{
820	return mem_pool__ce_calloc(find_mem_pool(istate), len);
821	}
822
823	struct cache_entry *make_empty_transient_cache_entry(size_t len,
824	struct mem_pool *ce_mem_pool)
825	{
826	if (ce_mem_pool)
827	return mem_pool__ce_calloc(ce_mem_pool, len);
828	return xcalloc(1, cache_entry_size(len));
829	}
830
831	enum verify_path_result {
832	PATH_OK,
833	PATH_INVALID,
834	PATH_DIR_WITH_SEP,
835	};
836
837	static enum verify_path_result verify_path_internal(const char *, unsigned);
838
839	int verify_path(const char *path, unsigned mode)
840	{
841	return verify_path_internal(path, mode) == PATH_OK;
842	}
843
844	struct cache_entry make_cache_entry(struct index_state istate,
845	unsigned int mode,
846	const struct object_id *oid,
847	const char *path,
848	int stage,
849	unsigned int refresh_options)
850	{
851	struct cache_entry ce, ret;
852	int len;
853
854	if (verify_path_internal(path, mode) == PATH_INVALID) {
855	error(_("invalid path '%s'"), path);
856	return NULL;
857	}
858
859	len = strlen(path);
860	ce = make_empty_cache_entry(istate, len);
861
862	oidcpy(&ce->oid, oid);
863	memcpy(ce->name, path, len);
864	ce->ce_flags = create_ce_flags(stage);
865	ce->ce_namelen = len;
866	ce->ce_mode = create_ce_mode(mode);
867
868	ret = refresh_cache_entry(istate, ce, refresh_options);
869	if (ret != ce)
870	discard_cache_entry(ce);
871	return ret;
872	}
873
874	struct cache_entry *make_transient_cache_entry(unsigned int mode,
875	const struct object_id *oid,
876	const char *path,
877	int stage,
878	struct mem_pool *ce_mem_pool)
879	{
880	struct cache_entry *ce;
881	int len;
882
883	if (!verify_path(path, mode)) {
884	error(_("invalid path '%s'"), path);
885	return NULL;
886	}
887
888	len = strlen(path);
889	ce = make_empty_transient_cache_entry(len, ce_mem_pool);
890
891	oidcpy(&ce->oid, oid);
892	memcpy(ce->name, path, len);
893	ce->ce_flags = create_ce_flags(stage);
894	ce->ce_namelen = len;
895	ce->ce_mode = create_ce_mode(mode);
896
897	return ce;
898	}
899
900	/*
901	* Chmod an index entry with either +x or -x.
902	*
903	* Returns -1 if the chmod for the particular cache entry failed (if it's
904	* not a regular file), -2 if an invalid flip argument is passed in, 0
905	* otherwise.
906	*/
907	int chmod_index_entry(struct index_state istate, struct cache_entry ce,
908	char flip)
909	{
910	if (!S_ISREG(ce->ce_mode))
911	return -1;
912	switch (flip) {
913	case '+':
914	ce->ce_mode \|= 0111;
915	break;
916	case '-':
917	ce->ce_mode &= ~0111;
918	break;
919	default:
920	return -2;
921	}
922	cache_tree_invalidate_path(istate, ce->name);
923	ce->ce_flags \|= CE_UPDATE_IN_BASE;
924	mark_fsmonitor_invalid(istate, ce);
925	istate->cache_changed \|= CE_ENTRY_CHANGED;
926
927	return 0;
928	}
929
930	int ce_same_name(const struct cache_entry a, const struct cache_entry b)
931	{
932	int len = ce_namelen(a);
933	return ce_namelen(b) == len && !memcmp(a->name, b->name, len);
934	}
935
936	/*
937	* We fundamentally don't like some paths: we don't want
938	* dot or dot-dot anywhere, and for obvious reasons don't
939	* want to recurse into ".git" either.
940	*
941	* Also, we don't want double slashes or slashes at the
942	* end that can make pathnames ambiguous.
943	*/
944	static int verify_dotfile(const char *rest, unsigned mode)
945	{
946	/*
947	* The first character was '.', but that
948	* has already been discarded, we now test
949	* the rest.
950	*/
951
952	/* "." is not allowed */
953	if (rest == '\0' \|\| is_dir_sep(rest))
954	return 0;
955
956	switch (*rest) {
957	/*
958	* ".git" followed by NUL or slash is bad. Note that we match
959	* case-insensitively here, even if ignore_case is not set.
960	* This outlaws ".GIT" everywhere out of an abundance of caution,
961	* since there's really no good reason to allow it.
962	*
963	* Once we've seen ".git", we can also find ".gitmodules", etc (also
964	* case-insensitively).
965	*/
966	case 'g':
967	case 'G':
968	if (rest[1] != 'i' && rest[1] != 'I')
969	break;
970	if (rest[2] != 't' && rest[2] != 'T')
971	break;
972	if (rest[3] == '\0' \|\| is_dir_sep(rest[3]))
973	return 0;
974	if (S_ISLNK(mode)) {
975	rest += 3;
976	if (skip_iprefix(rest, "modules", &rest) &&
977	(rest == '\0' \|\| is_dir_sep(rest)))
978	return 0;
979	}
980	break;
981	case '.':
982	if (rest[1] == '\0' \|\| is_dir_sep(rest[1]))
983	return 0;
984	}
985	return 1;
986	}
987
988	static enum verify_path_result verify_path_internal(const char *path,
989	unsigned mode)
990	{
991	char c = 0;
992
993	if (has_dos_drive_prefix(path))
994	return PATH_INVALID;
995
996	if (!is_valid_path(path))
997	return PATH_INVALID;
998
999	goto inside;
1000	for (;;) {
1001	if (!c)
1002	return PATH_OK;
1003	if (is_dir_sep(c)) {
1004	inside:
1005	if (protect_hfs) {
1006
1007	if (is_hfs_dotgit(path))
1008	return PATH_INVALID;
1009	if (S_ISLNK(mode)) {
1010	if (is_hfs_dotgitmodules(path))
1011	return PATH_INVALID;
1012	}
1013	}
1014	if (protect_ntfs) {
1015	#if defined GIT_WINDOWS_NATIVE \|\| defined __CYGWIN__
1016	if (c == '\\')
1017	return PATH_INVALID;
1018	#endif
1019	if (is_ntfs_dotgit(path))
1020	return PATH_INVALID;
1021	if (S_ISLNK(mode)) {
1022	if (is_ntfs_dotgitmodules(path))
1023	return PATH_INVALID;
1024	}
1025	}
1026
1027	c = *path++;
1028	if ((c == '.' && !verify_dotfile(path, mode)) \|\|
1029	is_dir_sep(c))
1030	return PATH_INVALID;
1031	/*
1032	* allow terminating directory separators for
1033	* sparse directory entries.
1034	*/
1035	if (c == '\0')
1036	return S_ISDIR(mode) ? PATH_DIR_WITH_SEP :
1037	PATH_INVALID;
1038	} else if (c == '\\' && protect_ntfs) {
1039	if (is_ntfs_dotgit(path))
1040	return PATH_INVALID;
1041	if (S_ISLNK(mode)) {
1042	if (is_ntfs_dotgitmodules(path))
1043	return PATH_INVALID;
1044	}
1045	}
1046
1047	c = *path++;
1048	}
1049	}
1050
1051	/*
1052	* Do we have another file that has the beginning components being a
1053	* proper superset of the name we're trying to add?
1054	*/
1055	static int has_file_name(struct index_state *istate,
1056	const struct cache_entry *ce, int pos, int ok_to_replace)
1057	{
1058	int retval = 0;
1059	int len = ce_namelen(ce);
1060	int stage = ce_stage(ce);
1061	const char *name = ce->name;
1062
1063	while (pos < istate->cache_nr) {
1064	struct cache_entry *p = istate->cache[pos++];
1065
1066	if (len >= ce_namelen(p))
1067	break;
1068	if (memcmp(name, p->name, len))
1069	break;
1070	if (ce_stage(p) != stage)
1071	continue;
1072	if (p->name[len] != '/')
1073	continue;
1074	if (p->ce_flags & CE_REMOVE)
1075	continue;
1076	retval = -1;
1077	if (!ok_to_replace)
1078	break;
1079	remove_index_entry_at(istate, --pos);
1080	}
1081	return retval;
1082	}
1083
1084
1085	/*
1086	* Like strcmp(), but also return the offset of the first change.
1087	* If strings are equal, return the length.
1088	*/
1089	int strcmp_offset(const char s1, const char s2, size_t *first_change)
1090	{
1091	size_t k;
1092
1093	if (!first_change)
1094	return strcmp(s1, s2);
1095
1096	for (k = 0; s1[k] == s2[k]; k++)
1097	if (s1[k] == '\0')
1098	break;
1099
1100	*first_change = k;
1101	return (unsigned char)s1[k] - (unsigned char)s2[k];
1102	}
1103
1104	/*
1105	* Do we have another file with a pathname that is a proper
1106	* subset of the name we're trying to add?
1107	*
1108	* That is, is there another file in the index with a path
1109	* that matches a sub-directory in the given entry?
1110	*/
1111	static int has_dir_name(struct index_state *istate,
1112	const struct cache_entry *ce, int pos, int ok_to_replace)
1113	{
1114	int retval = 0;
1115	int stage = ce_stage(ce);
1116	const char *name = ce->name;
1117	const char *slash = name + ce_namelen(ce);
1118	size_t len_eq_last;
1119	int cmp_last = 0;
1120
1121	/*
1122	* We are frequently called during an iteration on a sorted
1123	* list of pathnames and while building a new index. Therefore,
1124	* there is a high probability that this entry will eventually
1125	* be appended to the index, rather than inserted in the middle.
1126	* If we can confirm that, we can avoid binary searches on the
1127	* components of the pathname.
1128	*
1129	* Compare the entry's full path with the last path in the index.
1130	*/
1131	if (!istate->cache_nr)
1132	return 0;
1133
1134	cmp_last = strcmp_offset(name,
1135	istate->cache[istate->cache_nr - 1]->name,
1136	&len_eq_last);
1137	if (cmp_last > 0 && name[len_eq_last] != '/')
1138	/*
1139	* The entry sorts AFTER the last one in the
1140	* index and their paths have no common prefix,
1141	* so there cannot be a F/D conflict.
1142	*/
1143	return 0;
1144
1145	for (;;) {
1146	size_t len;
1147
1148	for (;;) {
1149	if (*--slash == '/')
1150	break;
1151	if (slash <= ce->name)
1152	return retval;
1153	}
1154	len = slash - name;
1155
1156	pos = index_name_stage_pos(istate, name, len, stage, EXPAND_SPARSE);
1157	if (pos >= 0) {
1158	/*
1159	* Found one, but not so fast. This could
1160	* be a marker that says "I was here, but
1161	* I am being removed". Such an entry is
1162	* not a part of the resulting tree, and
1163	* it is Ok to have a directory at the same
1164	* path.
1165	*/
1166	if (!(istate->cache[pos]->ce_flags & CE_REMOVE)) {
1167	retval = -1;
1168	if (!ok_to_replace)
1169	break;
1170	remove_index_entry_at(istate, pos);
1171	continue;
1172	}
1173	}
1174	else
1175	pos = -pos-1;
1176
1177	/*
1178	* Trivial optimization: if we find an entry that
1179	* already matches the sub-directory, then we know
1180	* we're ok, and we can exit.
1181	*/
1182	while (pos < istate->cache_nr) {
1183	struct cache_entry *p = istate->cache[pos];
1184	if ((ce_namelen(p) <= len) \|\|
1185	(p->name[len] != '/') \|\|
1186	memcmp(p->name, name, len))
1187	break; /* not our subdirectory */
1188	if (ce_stage(p) == stage && !(p->ce_flags & CE_REMOVE))
1189	/*
1190	* p is at the same stage as our entry, and
1191	* is a subdirectory of what we are looking
1192	* at, so we cannot have conflicts at our
1193	* level or anything shorter.
1194	*/
1195	return retval;
1196	pos++;
1197	}
1198	}
1199	return retval;
1200	}
1201
1202	/* We may be in a situation where we already have path/file and path
1203	* is being added, or we already have path and path/file is being
1204	* added. Either one would result in a nonsense tree that has path
1205	* twice when git-write-tree tries to write it out. Prevent it.
1206	*
1207	* If ok-to-replace is specified, we remove the conflicting entries
1208	* from the cache so the caller should recompute the insert position.
1209	* When this happens, we return non-zero.
1210	*/
1211	static int check_file_directory_conflict(struct index_state *istate,
1212	const struct cache_entry *ce,
1213	int pos, int ok_to_replace)
1214	{
1215	int retval;
1216
1217	/*
1218	* When ce is an "I am going away" entry, we allow it to be added
1219	*/
1220	if (ce->ce_flags & CE_REMOVE)
1221	return 0;
1222
1223	/*
1224	* We check if the path is a sub-path of a subsequent pathname
1225	* first, since removing those will not change the position
1226	* in the array.
1227	*/
1228	retval = has_file_name(istate, ce, pos, ok_to_replace);
1229
1230	/*
1231	* Then check if the path might have a clashing sub-directory
1232	* before it.
1233	*/
1234	return retval + has_dir_name(istate, ce, pos, ok_to_replace);
1235	}
1236
1237	static int add_index_entry_with_check(struct index_state istate, struct cache_entry ce, int option)
1238	{
1239	int pos;
1240	int ok_to_add = option & ADD_CACHE_OK_TO_ADD;
1241	int ok_to_replace = option & ADD_CACHE_OK_TO_REPLACE;
1242	int skip_df_check = option & ADD_CACHE_SKIP_DFCHECK;
1243	int new_only = option & ADD_CACHE_NEW_ONLY;
1244
1245	/*
1246	* If this entry's path sorts after the last entry in the index,
1247	* we can avoid searching for it.
1248	*/
1249	if (istate->cache_nr > 0 &&
1250	strcmp(ce->name, istate->cache[istate->cache_nr - 1]->name) > 0)
1251	pos = index_pos_to_insert_pos(istate->cache_nr);
1252	else
1253	pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce), EXPAND_SPARSE);
1254
1255	/*
1256	* Cache tree path should be invalidated only after index_name_stage_pos,
1257	* in case it expands a sparse index.
1258	*/
1259	if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
1260	cache_tree_invalidate_path(istate, ce->name);
1261
1262	/* existing match? Just replace it. */
1263	if (pos >= 0) {
1264	if (!new_only)
1265	replace_index_entry(istate, pos, ce);
1266	return 0;
1267	}
1268	pos = -pos-1;
1269
1270	if (!(option & ADD_CACHE_KEEP_CACHE_TREE))
1271	untracked_cache_add_to_index(istate, ce->name);
1272
1273	/*
1274	* Inserting a merged entry ("stage 0") into the index
1275	* will always replace all non-merged entries..
1276	*/
1277	if (pos < istate->cache_nr && ce_stage(ce) == 0) {
1278	while (ce_same_name(istate->cache[pos], ce)) {
1279	ok_to_add = 1;
1280	if (!remove_index_entry_at(istate, pos))
1281	break;
1282	}
1283	}
1284
1285	if (!ok_to_add)
1286	return -1;
1287	if (verify_path_internal(ce->name, ce->ce_mode) == PATH_INVALID)
1288	return error(_("invalid path '%s'"), ce->name);
1289
1290	if (!skip_df_check &&
1291	check_file_directory_conflict(istate, ce, pos, ok_to_replace)) {
1292	if (!ok_to_replace)
1293	return error(_("'%s' appears as both a file and as a directory"),
1294	ce->name);
1295	pos = index_name_stage_pos(istate, ce->name, ce_namelen(ce), ce_stage(ce), EXPAND_SPARSE);
1296	pos = -pos-1;
1297	}
1298	return pos + 1;
1299	}
1300
1301	int add_index_entry(struct index_state istate, struct cache_entry ce, int option)
1302	{
1303	int pos;
1304
1305	if (option & ADD_CACHE_JUST_APPEND)
1306	pos = istate->cache_nr;
1307	else {
1308	int ret;
1309	ret = add_index_entry_with_check(istate, ce, option);
1310	if (ret <= 0)
1311	return ret;
1312	pos = ret - 1;
1313	}
1314
1315	/* Make sure the array is big enough .. */
1316	ALLOC_GROW(istate->cache, istate->cache_nr + 1, istate->cache_alloc);
1317
1318	/* Add it in.. */
1319	istate->cache_nr++;
1320	if (istate->cache_nr > pos + 1)
1321	MOVE_ARRAY(istate->cache + pos + 1, istate->cache + pos,
1322	istate->cache_nr - pos - 1);
1323	set_index_entry(istate, pos, ce);
1324	istate->cache_changed \|= CE_ENTRY_ADDED;
1325	return 0;
1326	}
1327
1328	/*
1329	* "refresh" does not calculate a new sha1 file or bring the
1330	* cache up-to-date for mode/content changes. But what it
1331	* _does_ do is to "re-match" the stat information of a file
1332	* with the cache, so that you can refresh the cache for a
1333	* file that hasn't been changed but where the stat entry is
1334	* out of date.
1335	*
1336	* For example, you'd want to do this after doing a "git-read-tree",
1337	* to link up the stat cache details with the proper files.
1338	*/
1339	static struct cache_entry refresh_cache_ent(struct index_state istate,
1340	struct cache_entry *ce,
1341	unsigned int options, int *err,
1342	int *changed_ret,
1343	int *t2_did_lstat,
1344	int *t2_did_scan)
1345	{
1346	struct stat st;
1347	struct cache_entry *updated;
1348	int changed;
1349	int refresh = options & CE_MATCH_REFRESH;
1350	int ignore_valid = options & CE_MATCH_IGNORE_VALID;
1351	int ignore_skip_worktree = options & CE_MATCH_IGNORE_SKIP_WORKTREE;
1352	int ignore_missing = options & CE_MATCH_IGNORE_MISSING;
1353	int ignore_fsmonitor = options & CE_MATCH_IGNORE_FSMONITOR;
1354
1355	if (!refresh \|\| ce_uptodate(ce))
1356	return ce;
1357
1358	if (!ignore_fsmonitor)
1359	refresh_fsmonitor(istate);
1360	/*
1361	* CE_VALID or CE_SKIP_WORKTREE means the user promised us
1362	* that the change to the work tree does not matter and told
1363	* us not to worry.
1364	*/
1365	if (!ignore_skip_worktree && ce_skip_worktree(ce)) {
1366	ce_mark_uptodate(ce);
1367	return ce;
1368	}
1369	if (!ignore_valid && (ce->ce_flags & CE_VALID)) {
1370	ce_mark_uptodate(ce);
1371	return ce;
1372	}
1373	if (!ignore_fsmonitor && (ce->ce_flags & CE_FSMONITOR_VALID)) {
1374	ce_mark_uptodate(ce);
1375	return ce;
1376	}
1377
1378	if (has_symlink_leading_path(ce->name, ce_namelen(ce))) {
1379	if (ignore_missing)
1380	return ce;
1381	if (err)
1382	*err = ENOENT;
1383	return NULL;
1384	}
1385
1386	if (t2_did_lstat)
1387	*t2_did_lstat = 1;
1388	if (lstat(ce->name, &st) < 0) {
1389	if (ignore_missing && errno == ENOENT)
1390	return ce;
1391	if (err)
1392	*err = errno;
1393	return NULL;
1394	}
1395
1396	changed = ie_match_stat(istate, ce, &st, options);
1397	if (changed_ret)
1398	*changed_ret = changed;
1399	if (!changed) {
1400	/*
1401	* The path is unchanged. If we were told to ignore
1402	* valid bit, then we did the actual stat check and
1403	* found that the entry is unmodified. If the entry
1404	* is not marked VALID, this is the place to mark it
1405	* valid again, under "assume unchanged" mode.
1406	*/
1407	if (ignore_valid && assume_unchanged &&
1408	!(ce->ce_flags & CE_VALID))
1409	; /* mark this one VALID again */
1410	else {
1411	/*
1412	* We do not mark the index itself "modified"
1413	* because CE_UPTODATE flag is in-core only;
1414	* we are not going to write this change out.
1415	*/
1416	if (!S_ISGITLINK(ce->ce_mode)) {
1417	ce_mark_uptodate(ce);
1418	mark_fsmonitor_valid(istate, ce);
1419	}
1420	return ce;
1421	}
1422	}
1423
1424	if (t2_did_scan)
1425	*t2_did_scan = 1;
1426	if (ie_modified(istate, ce, &st, options)) {
1427	if (err)
1428	*err = EINVAL;
1429	return NULL;
1430	}
1431
1432	updated = make_empty_cache_entry(istate, ce_namelen(ce));
1433	copy_cache_entry(updated, ce);
1434	memcpy(updated->name, ce->name, ce->ce_namelen + 1);
1435	fill_stat_cache_info(istate, updated, &st);
1436	/*
1437	* If ignore_valid is not set, we should leave CE_VALID bit
1438	* alone. Otherwise, paths marked with --no-assume-unchanged
1439	* (i.e. things to be edited) will reacquire CE_VALID bit
1440	* automatically, which is not really what we want.
1441	*/
1442	if (!ignore_valid && assume_unchanged &&
1443	!(ce->ce_flags & CE_VALID))
1444	updated->ce_flags &= ~CE_VALID;
1445
1446	/* istate->cache_changed is updated in the caller */
1447	return updated;
1448	}
1449
1450	static void show_file(const char * fmt, const char * name, int in_porcelain,
1451	int * first, const char *header_msg)
1452	{
1453	if (in_porcelain && *first && header_msg) {
1454	printf("%s\n", header_msg);
1455	*first = 0;
1456	}
1457	printf(fmt, name);
1458	}
1459
1460	int repo_refresh_and_write_index(struct repository *repo,
1461	unsigned int refresh_flags,
1462	unsigned int write_flags,
1463	int gentle,
1464	const struct pathspec *pathspec,
1465	char seen, const char header_msg)
1466	{
1467	struct lock_file lock_file = LOCK_INIT;
1468	int fd, ret = 0;
1469
1470	fd = repo_hold_locked_index(repo, &lock_file,
1471	gentle ? 0 : LOCK_REPORT_ON_ERROR);
1472	if (!gentle && fd < 0)
1473	return -1;
1474	if (refresh_index(repo->index, refresh_flags, pathspec, seen, header_msg))
1475	ret = 1;
1476	if (0 <= fd && write_locked_index(repo->index, &lock_file, COMMIT_LOCK \| write_flags))
1477	ret = -1;
1478	return ret;
1479	}
1480
1481
1482	int refresh_index(struct index_state *istate, unsigned int flags,
1483	const struct pathspec *pathspec,
1484	char seen, const char header_msg)
1485	{
1486	int i;
1487	int has_errors = 0;
1488	int really = (flags & REFRESH_REALLY) != 0;
1489	int allow_unmerged = (flags & REFRESH_UNMERGED) != 0;
1490	int quiet = (flags & REFRESH_QUIET) != 0;
1491	int not_new = (flags & REFRESH_IGNORE_MISSING) != 0;
1492	int ignore_submodules = (flags & REFRESH_IGNORE_SUBMODULES) != 0;
1493	int ignore_skip_worktree = (flags & REFRESH_IGNORE_SKIP_WORKTREE) != 0;
1494	int first = 1;
1495	int in_porcelain = (flags & REFRESH_IN_PORCELAIN);
1496	unsigned int options = (CE_MATCH_REFRESH \|
1497	(really ? CE_MATCH_IGNORE_VALID : 0) \|
1498	(not_new ? CE_MATCH_IGNORE_MISSING : 0));
1499	const char *modified_fmt;
1500	const char *deleted_fmt;
1501	const char *typechange_fmt;
1502	const char *added_fmt;
1503	const char *unmerged_fmt;
1504	struct progress *progress = NULL;
1505	int t2_sum_lstat = 0;
1506	int t2_sum_scan = 0;
1507
1508	if (flags & REFRESH_PROGRESS && isatty(2))
1509	progress = start_delayed_progress(the_repository,
1510	_("Refresh index"),
1511	istate->cache_nr);
1512
1513	trace_performance_enter();
1514	modified_fmt = in_porcelain ? "M\t%s\n" : "%s: needs update\n";
1515	deleted_fmt = in_porcelain ? "D\t%s\n" : "%s: needs update\n";
1516	typechange_fmt = in_porcelain ? "T\t%s\n" : "%s: needs update\n";
1517	added_fmt = in_porcelain ? "A\t%s\n" : "%s: needs update\n";
1518	unmerged_fmt = in_porcelain ? "U\t%s\n" : "%s: needs merge\n";
1519	/*
1520	* Use the multi-threaded preload_index() to refresh most of the
1521	* cache entries quickly then in the single threaded loop below,
1522	* we only have to do the special cases that are left.
1523	*/
1524	preload_index(istate, pathspec, 0);
1525	trace2_region_enter("index", "refresh", NULL);
1526
1527	for (i = 0; i < istate->cache_nr; i++) {
1528	struct cache_entry ce, new_entry;
1529	int cache_errno = 0;
1530	int changed = 0;
1531	int filtered = 0;
1532	int t2_did_lstat = 0;
1533	int t2_did_scan = 0;
1534
1535	ce = istate->cache[i];
1536	if (ignore_submodules && S_ISGITLINK(ce->ce_mode))
1537	continue;
1538	if (ignore_skip_worktree && ce_skip_worktree(ce))
1539	continue;
1540
1541	/*
1542	* If this entry is a sparse directory, then there isn't
1543	* any stat() information to update. Ignore the entry.
1544	*/
1545	if (S_ISSPARSEDIR(ce->ce_mode))
1546	continue;
1547
1548	if (pathspec && !ce_path_match(istate, ce, pathspec, seen))
1549	filtered = 1;
1550
1551	if (ce_stage(ce)) {
1552	while ((i < istate->cache_nr) &&
1553	! strcmp(istate->cache[i]->name, ce->name))
1554	i++;
1555	i--;
1556	if (allow_unmerged)
1557	continue;
1558	if (!filtered)
1559	show_file(unmerged_fmt, ce->name, in_porcelain,
1560	&first, header_msg);
1561	has_errors = 1;
1562	continue;
1563	}
1564
1565	if (filtered)
1566	continue;
1567
1568	new_entry = refresh_cache_ent(istate, ce, options,
1569	&cache_errno, &changed,
1570	&t2_did_lstat, &t2_did_scan);
1571	t2_sum_lstat += t2_did_lstat;
1572	t2_sum_scan += t2_did_scan;
1573	if (new_entry == ce)
1574	continue;
1575	display_progress(progress, i);
1576	if (!new_entry) {
1577	const char *fmt;
1578
1579	if (really && cache_errno == EINVAL) {
1580	/* If we are doing --really-refresh that
1581	* means the index is not valid anymore.
1582	*/
1583	ce->ce_flags &= ~CE_VALID;
1584	ce->ce_flags \|= CE_UPDATE_IN_BASE;
1585	mark_fsmonitor_invalid(istate, ce);
1586	istate->cache_changed \|= CE_ENTRY_CHANGED;
1587	}
1588	if (quiet)
1589	continue;
1590
1591	if (cache_errno == ENOENT)
1592	fmt = deleted_fmt;
1593	else if (ce_intent_to_add(ce))
1594	fmt = added_fmt; /* must be before other checks */
1595	else if (changed & TYPE_CHANGED)
1596	fmt = typechange_fmt;
1597	else
1598	fmt = modified_fmt;
1599	show_file(fmt,
1600	ce->name, in_porcelain, &first, header_msg);
1601	has_errors = 1;
1602	continue;
1603	}
1604
1605	replace_index_entry(istate, i, new_entry);
1606	}
1607	trace2_data_intmax("index", NULL, "refresh/sum_lstat", t2_sum_lstat);
1608	trace2_data_intmax("index", NULL, "refresh/sum_scan", t2_sum_scan);
1609	trace2_region_leave("index", "refresh", NULL);
1610	display_progress(progress, istate->cache_nr);
1611	stop_progress(&progress);
1612	trace_performance_leave("refresh index");
1613	return has_errors;
1614	}
1615
1616	struct cache_entry refresh_cache_entry(struct index_state istate,
1617	struct cache_entry *ce,
1618	unsigned int options)
1619	{
1620	return refresh_cache_ent(istate, ce, options, NULL, NULL, NULL, NULL);
1621	}
1622
1623
1624	/*****************************************************************
1625	* Index File I/O
1626	*****************************************************************/
1627
1628	#define INDEX_FORMAT_DEFAULT 3
1629
1630	static unsigned int get_index_format_default(struct repository *r)
1631	{
1632	char *envversion = getenv("GIT_INDEX_VERSION");
1633	char *endp;
1634	unsigned int version = INDEX_FORMAT_DEFAULT;
1635
1636	if (!envversion) {
1637	prepare_repo_settings(r);
1638
1639	if (r->settings.index_version >= 0)
1640	version = r->settings.index_version;
1641	if (version < INDEX_FORMAT_LB \|\| INDEX_FORMAT_UB < version) {
1642	warning(_("index.version set, but the value is invalid.\n"
1643	"Using version %i"), INDEX_FORMAT_DEFAULT);
1644	return INDEX_FORMAT_DEFAULT;
1645	}
1646	return version;
1647	}
1648
1649	version = strtoul(envversion, &endp, 10);
1650	if (*endp \|\|
1651	version < INDEX_FORMAT_LB \|\| INDEX_FORMAT_UB < version) {
1652	warning(_("GIT_INDEX_VERSION set, but the value is invalid.\n"
1653	"Using version %i"), INDEX_FORMAT_DEFAULT);
1654	version = INDEX_FORMAT_DEFAULT;
1655	}
1656	return version;
1657	}
1658
1659	/*
1660	* dev/ino/uid/gid/size are also just tracked to the low 32 bits
1661	* Again - this is just a (very strong in practice) heuristic that
1662	* the inode hasn't changed.
1663	*
1664	* We save the fields in big-endian order to allow using the
1665	* index file over NFS transparently.
1666	*/
1667	struct ondisk_cache_entry {
1668	struct cache_time ctime;
1669	struct cache_time mtime;
1670	uint32_t dev;
1671	uint32_t ino;
1672	uint32_t mode;
1673	uint32_t uid;
1674	uint32_t gid;
1675	uint32_t size;
1676	/*
1677	* unsigned char hash[hashsz];
1678	* uint16_t flags;
1679	* if (flags & CE_EXTENDED)
1680	* uint16_t flags2;
1681	*/
1682	unsigned char data[GIT_MAX_RAWSZ + 2 * sizeof(uint16_t)];
1683	char name[FLEX_ARRAY];
1684	};
1685
1686	/* These are only used for v3 or lower */
1687	#define align_padding_size(size, len) ((size + (len) + 8) & ~7) - (size + len)
1688	#define align_flex_name(STRUCT,len) ((offsetof(struct STRUCT,data) + (len) + 8) & ~7)
1689	#define ondisk_cache_entry_size(len) align_flex_name(ondisk_cache_entry,len)
1690	#define ondisk_data_size(flags, len) (the_hash_algo->rawsz + \
1691	((flags & CE_EXTENDED) ? 2 : 1) * sizeof(uint16_t) + len)
1692	#define ondisk_data_size_max(len) (ondisk_data_size(CE_EXTENDED, len))
1693	#define ondisk_ce_size(ce) (ondisk_cache_entry_size(ondisk_data_size((ce)->ce_flags, ce_namelen(ce))))
1694
1695	/* Allow fsck to force verification of the index checksum. */
1696	int verify_index_checksum;
1697
1698	/* Allow fsck to force verification of the cache entry order. */
1699	int verify_ce_order;
1700
1701	static int verify_hdr(const struct cache_header *hdr, unsigned long size)
1702	{
1703	struct git_hash_ctx c;
1704	unsigned char hash[GIT_MAX_RAWSZ];
1705	int hdr_version;
1706	unsigned char start, end;
1707	struct object_id oid;
1708
1709	if (hdr->hdr_signature != htonl(CACHE_SIGNATURE))
1710	return error(_("bad signature 0x%08x"), hdr->hdr_signature);
1711	hdr_version = ntohl(hdr->hdr_version);
1712	if (hdr_version < INDEX_FORMAT_LB \|\| INDEX_FORMAT_UB < hdr_version)
1713	return error(_("bad index version %d"), hdr_version);
1714
1715	if (!verify_index_checksum)
1716	return 0;
1717
1718	end = (unsigned char *)hdr + size;
1719	start = end - the_hash_algo->rawsz;
1720	oidread(&oid, start, the_repository->hash_algo);
1721	if (oideq(&oid, null_oid(the_hash_algo)))
1722	return 0;
1723
1724	the_hash_algo->init_fn(&c);
1725	git_hash_update(&c, hdr, size - the_hash_algo->rawsz);
1726	git_hash_final(hash, &c);
1727	if (!hasheq(hash, start, the_repository->hash_algo))
1728	return error(_("bad index file sha1 signature"));
1729	return 0;
1730	}
1731
1732	static int read_index_extension(struct index_state *istate,
1733	const char ext, const char data, unsigned long sz)
1734	{
1735	switch (CACHE_EXT(ext)) {
1736	case CACHE_EXT_TREE:
1737	istate->cache_tree = cache_tree_read(data, sz);
1738	break;
1739	case CACHE_EXT_RESOLVE_UNDO:
1740	istate->resolve_undo = resolve_undo_read(data, sz, the_hash_algo);
1741	break;
1742	case CACHE_EXT_LINK:
1743	if (read_link_extension(istate, data, sz))
1744	return -1;
1745	break;
1746	case CACHE_EXT_UNTRACKED:
1747	istate->untracked = read_untracked_extension(data, sz);
1748	break;
1749	case CACHE_EXT_FSMONITOR:
1750	read_fsmonitor_extension(istate, data, sz);
1751	break;
1752	case CACHE_EXT_ENDOFINDEXENTRIES:
1753	case CACHE_EXT_INDEXENTRYOFFSETTABLE:
1754	/* already handled in do_read_index() */
1755	break;
1756	case CACHE_EXT_SPARSE_DIRECTORIES:
1757	/* no content, only an indicator */
1758	istate->sparse_index = INDEX_COLLAPSED;
1759	break;
1760	default:
1761	if (ext < 'A' \|\| 'Z' < ext)
1762	return error(_("index uses %.4s extension, which we do not understand"),
1763	ext);
1764	fprintf_ln(stderr, _("ignoring %.4s extension"), ext);
1765	break;
1766	}
1767	return 0;
1768	}
1769
1770	/*
1771	* Parses the contents of the cache entry contained within the 'ondisk' buffer
1772	* into a new incore 'cache_entry'.
1773	*
1774	* Note that 'char *ondisk' may not be aligned to a 4-byte address interval in
1775	* index v4, so we cannot cast it to 'struct ondisk_cache_entry *' and access
1776	* its members. Instead, we use the byte offsets of members within the struct to
1777	* identify where 'get_be16()', 'get_be32()', and 'oidread()' (which can all
1778	* read from an unaligned memory buffer) should read from the 'ondisk' buffer
1779	* into the corresponding incore 'cache_entry' members.
1780	*/
1781	static struct cache_entry create_from_disk(struct mem_pool ce_mem_pool,
1782	unsigned int version,
1783	const char *ondisk,
1784	unsigned long *ent_size,
1785	const struct cache_entry *previous_ce)
1786	{
1787	struct cache_entry *ce;
1788	size_t len;
1789	const char *name;
1790	const unsigned hashsz = the_hash_algo->rawsz;
1791	const char *flagsp = ondisk + offsetof(struct ondisk_cache_entry, data) + hashsz;
1792	unsigned int flags;
1793	size_t copy_len = 0;
1794	/*
1795	* Adjacent cache entries tend to share the leading paths, so it makes
1796	* sense to only store the differences in later entries. In the v4
1797	* on-disk format of the index, each on-disk cache entry stores the
1798	* number of bytes to be stripped from the end of the previous name,
1799	* and the bytes to append to the result, to come up with its name.
1800	*/
1801	int expand_name_field = version == 4;
1802
1803	/* On-disk flags are just 16 bits */
1804	flags = get_be16(flagsp);
1805	len = flags & CE_NAMEMASK;
1806
1807	if (flags & CE_EXTENDED) {
1808	int extended_flags;
1809	extended_flags = get_be16(flagsp + sizeof(uint16_t)) << 16;
1810	/* We do not yet understand any bit out of CE_EXTENDED_FLAGS */
1811	if (extended_flags & ~CE_EXTENDED_FLAGS)
1812	die(_("unknown index entry format 0x%08x"), extended_flags);
1813	flags \|= extended_flags;
1814	name = (const char )(flagsp + 2 sizeof(uint16_t));
1815	}
1816	else
1817	name = (const char *)(flagsp + sizeof(uint16_t));
1818
1819	if (expand_name_field) {
1820	const unsigned char cp = (const unsigned char )name;
1821	uint64_t strip_len, previous_len;
1822
1823	/* If we're at the beginning of a block, ignore the previous name */
1824	strip_len = decode_varint(&cp);
1825	if (previous_ce) {
1826	previous_len = previous_ce->ce_namelen;
1827	if (previous_len < strip_len)
1828	die(_("malformed name field in the index, near path '%s'"),
1829	previous_ce->name);
1830	copy_len = previous_len - strip_len;
1831	}
1832	name = (const char *)cp;
1833	}
1834
1835	if (len == CE_NAMEMASK) {
1836	len = strlen(name);
1837	if (expand_name_field)
1838	len += copy_len;
1839	}
1840
1841	ce = mem_pool__ce_alloc(ce_mem_pool, len);
1842
1843	/*
1844	* NEEDSWORK: using 'offsetof()' is cumbersome and should be replaced
1845	* with something more akin to 'load_bitmap_entries_v1()'s use of
1846	* 'read_be16'/'read_be32'. For consistency with the corresponding
1847	* ondisk entry write function ('copy_cache_entry_to_ondisk()'), this
1848	* should be done at the same time as removing references to
1849	* 'ondisk_cache_entry' there.
1850	*/
1851	ce->ce_stat_data.sd_ctime.sec = get_be32(ondisk + offsetof(struct ondisk_cache_entry, ctime)
1852	+ offsetof(struct cache_time, sec));
1853	ce->ce_stat_data.sd_mtime.sec = get_be32(ondisk + offsetof(struct ondisk_cache_entry, mtime)
1854	+ offsetof(struct cache_time, sec));
1855	ce->ce_stat_data.sd_ctime.nsec = get_be32(ondisk + offsetof(struct ondisk_cache_entry, ctime)
1856	+ offsetof(struct cache_time, nsec));
1857	ce->ce_stat_data.sd_mtime.nsec = get_be32(ondisk + offsetof(struct ondisk_cache_entry, mtime)
1858	+ offsetof(struct cache_time, nsec));
1859	ce->ce_stat_data.sd_dev = get_be32(ondisk + offsetof(struct ondisk_cache_entry, dev));
1860	ce->ce_stat_data.sd_ino = get_be32(ondisk + offsetof(struct ondisk_cache_entry, ino));
1861	ce->ce_mode = get_be32(ondisk + offsetof(struct ondisk_cache_entry, mode));
1862	ce->ce_stat_data.sd_uid = get_be32(ondisk + offsetof(struct ondisk_cache_entry, uid));
1863	ce->ce_stat_data.sd_gid = get_be32(ondisk + offsetof(struct ondisk_cache_entry, gid));
1864	ce->ce_stat_data.sd_size = get_be32(ondisk + offsetof(struct ondisk_cache_entry, size));
1865	ce->ce_flags = flags & ~CE_NAMEMASK;
1866	ce->ce_namelen = len;
1867	ce->index = 0;
1868	oidread(&ce->oid, (const unsigned char *)ondisk + offsetof(struct ondisk_cache_entry, data),
1869	the_repository->hash_algo);
1870
1871	if (expand_name_field) {
1872	if (copy_len)
1873	memcpy(ce->name, previous_ce->name, copy_len);
1874	memcpy(ce->name + copy_len, name, len + 1 - copy_len);
1875	ent_size = (name - ((char )ondisk)) + len + 1 - copy_len;
1876	} else {
1877	memcpy(ce->name, name, len + 1);
1878	*ent_size = ondisk_ce_size(ce);
1879	}
1880	return ce;
1881	}
1882
1883	static void check_ce_order(struct index_state *istate)
1884	{
1885	unsigned int i;
1886
1887	if (!verify_ce_order)
1888	return;
1889
1890	for (i = 1; i < istate->cache_nr; i++) {
1891	struct cache_entry *ce = istate->cache[i - 1];
1892	struct cache_entry *next_ce = istate->cache[i];
1893	int name_compare = strcmp(ce->name, next_ce->name);
1894
1895	if (0 < name_compare)
1896	die(_("unordered stage entries in index"));
1897	if (!name_compare) {
1898	if (!ce_stage(ce))
1899	die(_("multiple stage entries for merged file '%s'"),
1900	ce->name);
1901	if (ce_stage(ce) > ce_stage(next_ce))
1902	die(_("unordered stage entries for '%s'"),
1903	ce->name);
1904	}
1905	}
1906	}
1907
1908	static void tweak_untracked_cache(struct index_state *istate)
1909	{
1910	struct repository *r = the_repository;
1911
1912	prepare_repo_settings(r);
1913
1914	switch (r->settings.core_untracked_cache) {
1915	case UNTRACKED_CACHE_REMOVE:
1916	remove_untracked_cache(istate);
1917	break;
1918	case UNTRACKED_CACHE_WRITE:
1919	add_untracked_cache(istate);
1920	break;
1921	case UNTRACKED_CACHE_KEEP:
1922	/*
1923	* Either an explicit "core.untrackedCache=keep", the
1924	* default if "core.untrackedCache" isn't configured,
1925	* or a fallback on an unknown "core.untrackedCache"
1926	* value.
1927	*/
1928	break;
1929	}
1930	}
1931
1932	static void tweak_split_index(struct index_state *istate)
1933	{
1934	switch (repo_config_get_split_index(the_repository)) {
1935	case -1: /* unset: do nothing */
1936	break;
1937	case 0: /* false */
1938	remove_split_index(istate);
1939	break;
1940	case 1: /* true */
1941	add_split_index(istate);
1942	break;
1943	default: /* unknown value: do nothing */
1944	break;
1945	}
1946	}
1947
1948	static void post_read_index_from(struct index_state *istate)
1949	{
1950	check_ce_order(istate);
1951	tweak_untracked_cache(istate);
1952	tweak_split_index(istate);
1953	tweak_fsmonitor(istate);
1954	}
1955
1956	static size_t estimate_cache_size_from_compressed(unsigned int entries)
1957	{
1958	return entries * (sizeof(struct cache_entry) + CACHE_ENTRY_PATH_LENGTH);
1959	}
1960
1961	static size_t estimate_cache_size(size_t ondisk_size, unsigned int entries)
1962	{
1963	long per_entry = sizeof(struct cache_entry) - sizeof(struct ondisk_cache_entry);
1964
1965	/*
1966	* Account for potential alignment differences.
1967	*/
1968	per_entry += align_padding_size(per_entry, 0);
1969	return ondisk_size + entries * per_entry;
1970	}
1971
1972	struct index_entry_offset
1973	{
1974	/* starting byte offset into index file, count of index entries in this block */
1975	int offset, nr;
1976	};
1977
1978	struct index_entry_offset_table
1979	{
1980	int nr;
1981	struct index_entry_offset entries[FLEX_ARRAY];
1982	};
1983
1984	static struct index_entry_offset_table read_ieot_extension(const char mmap, size_t mmap_size, size_t offset);
1985	static void write_ieot_extension(struct strbuf sb, struct index_entry_offset_table ieot);
1986
1987	static size_t read_eoie_extension(const char *mmap, size_t mmap_size);
1988	static void write_eoie_extension(struct strbuf sb, struct git_hash_ctx eoie_context, size_t offset);
1989
1990	struct load_index_extensions
1991	{
1992	pthread_t pthread;
1993	struct index_state *istate;
1994	const char *mmap;
1995	size_t mmap_size;
1996	unsigned long src_offset;
1997	};
1998
1999	static void load_index_extensions(void _data)
2000	{
2001	struct load_index_extensions *p = _data;
2002	unsigned long src_offset = p->src_offset;
2003
2004	while (src_offset <= p->mmap_size - the_hash_algo->rawsz - 8) {
2005	/* After an array of active_nr index entries,
2006	* there can be arbitrary number of extended
2007	* sections, each of which is prefixed with
2008	* extension name (4-byte) and section length
2009	* in 4-byte network byte order.
2010	*/
2011	uint32_t extsize = get_be32(p->mmap + src_offset + 4);
2012	if (read_index_extension(p->istate,
2013	p->mmap + src_offset,
2014	p->mmap + src_offset + 8,
2015	extsize) < 0) {
2016	munmap((void *)p->mmap, p->mmap_size);
2017	die(_("index file corrupt"));
2018	}
2019	src_offset += 8;
2020	src_offset += extsize;
2021	}
2022
2023	return NULL;
2024	}
2025
2026	/*
2027	* A helper function that will load the specified range of cache entries
2028	* from the memory mapped file and add them to the given index.
2029	*/
2030	static unsigned long load_cache_entry_block(struct index_state *istate,
2031	struct mem_pool ce_mem_pool, int offset, int nr, const char mmap,
2032	unsigned long start_offset, const struct cache_entry *previous_ce)
2033	{
2034	int i;
2035	unsigned long src_offset = start_offset;
2036
2037	for (i = offset; i < offset + nr; i++) {
2038	struct cache_entry *ce;
2039	unsigned long consumed;
2040
2041	ce = create_from_disk(ce_mem_pool, istate->version,
2042	mmap + src_offset,
2043	&consumed, previous_ce);
2044	set_index_entry(istate, i, ce);
2045
2046	src_offset += consumed;
2047	previous_ce = ce;
2048	}
2049	return src_offset - start_offset;
2050	}
2051
2052	static unsigned long load_all_cache_entries(struct index_state *istate,
2053	const char *mmap, size_t mmap_size, unsigned long src_offset)
2054	{
2055	unsigned long consumed;
2056
2057	istate->ce_mem_pool = xmalloc(sizeof(*istate->ce_mem_pool));
2058	if (istate->version == 4) {
2059	mem_pool_init(istate->ce_mem_pool,
2060	estimate_cache_size_from_compressed(istate->cache_nr));
2061	} else {
2062	mem_pool_init(istate->ce_mem_pool,
2063	estimate_cache_size(mmap_size, istate->cache_nr));
2064	}
2065
2066	consumed = load_cache_entry_block(istate, istate->ce_mem_pool,
2067	0, istate->cache_nr, mmap, src_offset, NULL);
2068	return consumed;
2069	}
2070
2071	/*
2072	* Mostly randomly chosen maximum thread counts: we
2073	* cap the parallelism to online_cpus() threads, and we want
2074	* to have at least 10000 cache entries per thread for it to
2075	* be worth starting a thread.
2076	*/
2077
2078	#define THREAD_COST (10000)
2079
2080	struct load_cache_entries_thread_data
2081	{
2082	pthread_t pthread;
2083	struct index_state *istate;
2084	struct mem_pool *ce_mem_pool;
2085	int offset;
2086	const char *mmap;
2087	struct index_entry_offset_table *ieot;
2088	int ieot_start; /* starting index into the ieot array */
2089	int ieot_blocks; /* count of ieot entries to process */
2090	unsigned long consumed; /* return # of bytes in index file processed */
2091	};
2092
2093	/*
2094	* A thread proc to run the load_cache_entries() computation
2095	* across multiple background threads.
2096	*/
2097	static void load_cache_entries_thread(void _data)
2098	{
2099	struct load_cache_entries_thread_data *p = _data;
2100	int i;
2101
2102	/* iterate across all ieot blocks assigned to this thread */
2103	for (i = p->ieot_start; i < p->ieot_start + p->ieot_blocks; i++) {
2104	p->consumed += load_cache_entry_block(p->istate, p->ce_mem_pool,
2105	p->offset, p->ieot->entries[i].nr, p->mmap, p->ieot->entries[i].offset, NULL);
2106	p->offset += p->ieot->entries[i].nr;
2107	}
2108	return NULL;
2109	}
2110
2111	static unsigned long load_cache_entries_threaded(struct index_state istate, const char mmap, size_t mmap_size,
2112	int nr_threads, struct index_entry_offset_table *ieot)
2113	{
2114	int i, offset, ieot_blocks, ieot_start, err;
2115	struct load_cache_entries_thread_data *data;
2116	unsigned long consumed = 0;
2117
2118	/* a little sanity checking */
2119	if (istate->name_hash_initialized)
2120	BUG("the name hash isn't thread safe");
2121
2122	istate->ce_mem_pool = xmalloc(sizeof(*istate->ce_mem_pool));
2123	mem_pool_init(istate->ce_mem_pool, 0);
2124
2125	/* ensure we have no more threads than we have blocks to process */
2126	if (nr_threads > ieot->nr)
2127	nr_threads = ieot->nr;
2128	CALLOC_ARRAY(data, nr_threads);
2129
2130	offset = ieot_start = 0;
2131	ieot_blocks = DIV_ROUND_UP(ieot->nr, nr_threads);
2132	for (i = 0; i < nr_threads; i++) {
2133	struct load_cache_entries_thread_data *p = &data[i];
2134	int nr, j;
2135
2136	if (ieot_start + ieot_blocks > ieot->nr)
2137	ieot_blocks = ieot->nr - ieot_start;
2138
2139	p->istate = istate;
2140	p->offset = offset;
2141	p->mmap = mmap;
2142	p->ieot = ieot;
2143	p->ieot_start = ieot_start;
2144	p->ieot_blocks = ieot_blocks;
2145
2146	/* create a mem_pool for each thread */
2147	nr = 0;
2148	for (j = p->ieot_start; j < p->ieot_start + p->ieot_blocks; j++)
2149	nr += p->ieot->entries[j].nr;
2150	p->ce_mem_pool = xmalloc(sizeof(*istate->ce_mem_pool));
2151	if (istate->version == 4) {
2152	mem_pool_init(p->ce_mem_pool,
2153	estimate_cache_size_from_compressed(nr));
2154	} else {
2155	mem_pool_init(p->ce_mem_pool,
2156	estimate_cache_size(mmap_size, nr));
2157	}
2158
2159	err = pthread_create(&p->pthread, NULL, load_cache_entries_thread, p);
2160	if (err)
2161	die(_("unable to create load_cache_entries thread: %s"), strerror(err));
2162
2163	/* increment by the number of cache entries in the ieot block being processed */
2164	for (j = 0; j < ieot_blocks; j++)
2165	offset += ieot->entries[ieot_start + j].nr;
2166	ieot_start += ieot_blocks;
2167	}
2168
2169	for (i = 0; i < nr_threads; i++) {
2170	struct load_cache_entries_thread_data *p = &data[i];
2171
2172	err = pthread_join(p->pthread, NULL);
2173	if (err)
2174	die(_("unable to join load_cache_entries thread: %s"), strerror(err));
2175	mem_pool_combine(istate->ce_mem_pool, p->ce_mem_pool);
2176	free(p->ce_mem_pool);
2177	consumed += p->consumed;
2178	}
2179
2180	free(data);
2181
2182	return consumed;
2183	}
2184
2185	static void set_new_index_sparsity(struct index_state *istate)
2186	{
2187	/*
2188	* If the index's repo exists, mark it sparse according to
2189	* repo settings.
2190	*/
2191	prepare_repo_settings(istate->repo);
2192	if (!istate->repo->settings.command_requires_full_index &&
2193	is_sparse_index_allowed(istate, 0))
2194	istate->sparse_index = 1;
2195	}
2196
2197	/* remember to discard_cache() before reading a different cache! */
2198	int do_read_index(struct index_state istate, const char path, int must_exist)
2199	{
2200	int fd;
2201	struct stat st;
2202	unsigned long src_offset;
2203	const struct cache_header *hdr;
2204	const char *mmap;
2205	size_t mmap_size;
2206	struct load_index_extensions p;
2207	size_t extension_offset = 0;
2208	int nr_threads, cpus;
2209	struct index_entry_offset_table *ieot = NULL;
2210
2211	if (istate->initialized)
2212	return istate->cache_nr;
2213
2214	istate->timestamp.sec = 0;
2215	istate->timestamp.nsec = 0;
2216	fd = open(path, O_RDONLY);
2217	if (fd < 0) {
2218	if (!must_exist && errno == ENOENT) {
2219	set_new_index_sparsity(istate);
2220	istate->initialized = 1;
2221	return 0;
2222	}
2223	die_errno(_("%s: index file open failed"), path);
2224	}
2225
2226	if (fstat(fd, &st))
2227	die_errno(_("%s: cannot stat the open index"), path);
2228
2229	mmap_size = xsize_t(st.st_size);
2230	if (mmap_size < sizeof(struct cache_header) + the_hash_algo->rawsz)
2231	die(_("%s: index file smaller than expected"), path);
2232
2233	mmap = xmmap_gently(NULL, mmap_size, PROT_READ, MAP_PRIVATE, fd, 0);
2234	if (mmap == MAP_FAILED)
2235	die_errno(_("%s: unable to map index file%s"), path,
2236	mmap_os_err());
2237	close(fd);
2238
2239	hdr = (const struct cache_header *)mmap;
2240	if (verify_hdr(hdr, mmap_size) < 0)
2241	goto unmap;
2242
2243	oidread(&istate->oid, (const unsigned char *)hdr + mmap_size - the_hash_algo->rawsz,
2244	the_repository->hash_algo);
2245	istate->version = ntohl(hdr->hdr_version);
2246	istate->cache_nr = ntohl(hdr->hdr_entries);
2247	istate->cache_alloc = alloc_nr(istate->cache_nr);
2248	CALLOC_ARRAY(istate->cache, istate->cache_alloc);
2249	istate->initialized = 1;
2250
2251	p.istate = istate;
2252	p.mmap = mmap;
2253	p.mmap_size = mmap_size;
2254
2255	src_offset = sizeof(*hdr);
2256
2257	if (repo_config_get_index_threads(the_repository, &nr_threads))
2258	nr_threads = 1;
2259
2260	/* TODO: does creating more threads than cores help? */
2261	if (!nr_threads) {
2262	nr_threads = istate->cache_nr / THREAD_COST;
2263	cpus = online_cpus();
2264	if (nr_threads > cpus)
2265	nr_threads = cpus;
2266	}
2267
2268	if (!HAVE_THREADS)
2269	nr_threads = 1;
2270
2271	if (nr_threads > 1) {
2272	extension_offset = read_eoie_extension(mmap, mmap_size);
2273	if (extension_offset) {
2274	int err;
2275
2276	p.src_offset = extension_offset;
2277	err = pthread_create(&p.pthread, NULL, load_index_extensions, &p);
2278	if (err)
2279	die(_("unable to create load_index_extensions thread: %s"), strerror(err));
2280
2281	nr_threads--;
2282	}
2283	}
2284
2285	/*
2286	* Locate and read the index entry offset table so that we can use it
2287	* to multi-thread the reading of the cache entries.
2288	*/
2289	if (extension_offset && nr_threads > 1)
2290	ieot = read_ieot_extension(mmap, mmap_size, extension_offset);
2291
2292	if (ieot) {
2293	src_offset += load_cache_entries_threaded(istate, mmap, mmap_size, nr_threads, ieot);
2294	free(ieot);
2295	} else {
2296	src_offset += load_all_cache_entries(istate, mmap, mmap_size, src_offset);
2297	}
2298
2299	istate->timestamp.sec = st.st_mtime;
2300	istate->timestamp.nsec = ST_MTIME_NSEC(st);
2301
2302	/* if we created a thread, join it otherwise load the extensions on the primary thread */
2303	if (extension_offset) {
2304	int ret = pthread_join(p.pthread, NULL);
2305	if (ret)
2306	die(_("unable to join load_index_extensions thread: %s"), strerror(ret));
2307	} else {
2308	p.src_offset = src_offset;
2309	load_index_extensions(&p);
2310	}
2311	munmap((void *)mmap, mmap_size);
2312
2313	trace2_data_intmax("index", istate->repo, "read/version",
2314	istate->version);
2315	trace2_data_intmax("index", istate->repo, "read/cache_nr",
2316	istate->cache_nr);
2317
2318	/*
2319	* If the command explicitly requires a full index, force it
2320	* to be full. Otherwise, correct the sparsity based on repository
2321	* settings and other properties of the index (if necessary).
2322	*/
2323	prepare_repo_settings(istate->repo);
2324	if (istate->repo->settings.command_requires_full_index)
2325	ensure_full_index(istate);
2326	else
2327	ensure_correct_sparsity(istate);
2328
2329	return istate->cache_nr;
2330
2331	unmap:
2332	munmap((void *)mmap, mmap_size);
2333	die(_("index file corrupt"));
2334	}
2335
2336	/*
2337	* Signal that the shared index is used by updating its mtime.
2338	*
2339	* This way, shared index can be removed if they have not been used
2340	* for some time.
2341	*/
2342	static void freshen_shared_index(const char *shared_index, int warn)
2343	{
2344	if (!check_and_freshen_file(shared_index, 1) && warn)
2345	warning(_("could not freshen shared index '%s'"), shared_index);
2346	}
2347
2348	int read_index_from(struct index_state istate, const char path,
2349	const char *gitdir)
2350	{
2351	struct split_index *split_index;
2352	int ret;
2353	char *base_oid_hex;
2354	char *base_path;
2355
2356	/* istate->initialized covers both .git/index and .git/sharedindex.xxx */
2357	if (istate->initialized)
2358	return istate->cache_nr;
2359
2360	trace2_region_enter_printf("index", "do_read_index", istate->repo,
2361	"%s", path);
2362	trace_performance_enter();
2363	ret = do_read_index(istate, path, 0);
2364	trace_performance_leave("read cache %s", path);
2365	trace2_region_leave_printf("index", "do_read_index", istate->repo,
2366	"%s", path);
2367
2368	split_index = istate->split_index;
2369	if (!split_index \|\| is_null_oid(&split_index->base_oid)) {
2370	post_read_index_from(istate);
2371	return ret;
2372	}
2373
2374	trace_performance_enter();
2375	if (split_index->base)
2376	release_index(split_index->base);
2377	else
2378	ALLOC_ARRAY(split_index->base, 1);
2379	index_state_init(split_index->base, istate->repo);
2380
2381	base_oid_hex = oid_to_hex(&split_index->base_oid);
2382	base_path = xstrfmt("%s/sharedindex.%s", gitdir, base_oid_hex);
2383	if (file_exists(base_path)) {
2384	trace2_region_enter_printf("index", "shared/do_read_index",
2385	the_repository, "%s", base_path);
2386
2387	ret = do_read_index(split_index->base, base_path, 0);
2388	trace2_region_leave_printf("index", "shared/do_read_index",
2389	the_repository, "%s", base_path);
2390	} else {
2391	char *path_copy = xstrdup(path);
2392	char *base_path2 = xstrfmt("%s/sharedindex.%s",
2393	dirname(path_copy), base_oid_hex);
2394	free(path_copy);
2395	trace2_region_enter_printf("index", "shared/do_read_index",
2396	the_repository, "%s", base_path2);
2397	ret = do_read_index(split_index->base, base_path2, 1);
2398	trace2_region_leave_printf("index", "shared/do_read_index",
2399	the_repository, "%s", base_path2);
2400	free(base_path2);
2401	}
2402	if (!oideq(&split_index->base_oid, &split_index->base->oid))
2403	die(_("broken index, expect %s in %s, got %s"),
2404	base_oid_hex, base_path,
2405	oid_to_hex(&split_index->base->oid));
2406
2407	freshen_shared_index(base_path, 0);
2408	merge_base_index(istate);
2409	post_read_index_from(istate);
2410	trace_performance_leave("read cache %s", base_path);
2411	free(base_path);
2412	return ret;
2413	}
2414
2415	int is_index_unborn(struct index_state *istate)
2416	{
2417	return (!istate->cache_nr && !istate->timestamp.sec);
2418	}
2419
2420	void index_state_init(struct index_state istate, struct repository r)
2421	{
2422	struct index_state blank = INDEX_STATE_INIT(r);
2423	memcpy(istate, &blank, sizeof(*istate));
2424	}
2425
2426	void release_index(struct index_state *istate)
2427	{
2428	/*
2429	* Cache entries in istate->cache[] should have been allocated
2430	* from the memory pool associated with this index, or from an
2431	* associated split_index. There is no need to free individual
2432	* cache entries. validate_cache_entries can detect when this
2433	* assertion does not hold.
2434	*/
2435	validate_cache_entries(istate);
2436
2437	resolve_undo_clear_index(istate);
2438	free_name_hash(istate);
2439	cache_tree_free(&(istate->cache_tree));
2440	free(istate->fsmonitor_last_update);
2441	free(istate->cache);
2442	discard_split_index(istate);
2443	free_untracked_cache(istate->untracked);
2444
2445	if (istate->sparse_checkout_patterns) {
2446	clear_pattern_list(istate->sparse_checkout_patterns);
2447	FREE_AND_NULL(istate->sparse_checkout_patterns);
2448	}
2449
2450	if (istate->ce_mem_pool) {
2451	mem_pool_discard(istate->ce_mem_pool, should_validate_cache_entries());
2452	FREE_AND_NULL(istate->ce_mem_pool);
2453	}
2454	}
2455
2456	void discard_index(struct index_state *istate)
2457	{
2458	release_index(istate);
2459	index_state_init(istate, istate->repo);
2460	}
2461
2462	/*
2463	* Validate the cache entries of this index.
2464	* All cache entries associated with this index
2465	* should have been allocated by the memory pool
2466	* associated with this index, or by a referenced
2467	* split index.
2468	*/
2469	void validate_cache_entries(const struct index_state *istate)
2470	{
2471	int i;
2472
2473	if (!should_validate_cache_entries() \|\|!istate \|\| !istate->initialized)
2474	return;
2475
2476	for (i = 0; i < istate->cache_nr; i++) {
2477	if (!istate) {
2478	BUG("cache entry is not allocated from expected memory pool");
2479	} else if (!istate->ce_mem_pool \|\|
2480	!mem_pool_contains(istate->ce_mem_pool, istate->cache[i])) {
2481	if (!istate->split_index \|\|
2482	!istate->split_index->base \|\|
2483	!istate->split_index->base->ce_mem_pool \|\|
2484	!mem_pool_contains(istate->split_index->base->ce_mem_pool, istate->cache[i])) {
2485	BUG("cache entry is not allocated from expected memory pool");
2486	}
2487	}
2488	}
2489
2490	if (istate->split_index)
2491	validate_cache_entries(istate->split_index->base);
2492	}
2493
2494	int unmerged_index(const struct index_state *istate)
2495	{
2496	int i;
2497	for (i = 0; i < istate->cache_nr; i++) {
2498	if (ce_stage(istate->cache[i]))
2499	return 1;
2500	}
2501	return 0;
2502	}
2503
2504	int repo_index_has_changes(struct repository *repo,
2505	struct tree *tree,
2506	struct strbuf *sb)
2507	{
2508	struct index_state *istate = repo->index;
2509	struct object_id cmp;
2510	int i;
2511
2512	if (tree)
2513	cmp = tree->object.oid;
2514	if (tree \|\| !repo_get_oid_tree(repo, "HEAD", &cmp)) {
2515	struct diff_options opt;
2516
2517	repo_diff_setup(repo, &opt);
2518	opt.flags.exit_with_status = 1;
2519	if (!sb)
2520	opt.flags.quick = 1;
2521	diff_setup_done(&opt);
2522	do_diff_cache(&cmp, &opt);
2523	diffcore_std(&opt);
2524	for (i = 0; sb && i < diff_queued_diff.nr; i++) {
2525	if (i)
2526	strbuf_addch(sb, ' ');
2527	strbuf_addstr(sb, diff_queued_diff.queue[i]->two->path);
2528	}
2529	diff_flush(&opt);
2530	return opt.flags.has_changes != 0;
2531	} else {
2532	/* TODO: audit for interaction with sparse-index. */
2533	ensure_full_index(istate);
2534	for (i = 0; sb && i < istate->cache_nr; i++) {
2535	if (i)
2536	strbuf_addch(sb, ' ');
2537	strbuf_addstr(sb, istate->cache[i]->name);
2538	}
2539	return !!istate->cache_nr;
2540	}
2541	}
2542
2543	static int write_index_ext_header(struct hashfile *f,
2544	struct git_hash_ctx *eoie_f,
2545	unsigned int ext,
2546	unsigned int sz)
2547	{
2548	hashwrite_be32(f, ext);
2549	hashwrite_be32(f, sz);
2550
2551	if (eoie_f) {
2552	ext = htonl(ext);
2553	sz = htonl(sz);
2554	git_hash_update(eoie_f, &ext, sizeof(ext));
2555	git_hash_update(eoie_f, &sz, sizeof(sz));
2556	}
2557	return 0;
2558	}
2559
2560	static void ce_smudge_racily_clean_entry(struct index_state *istate,
2561	struct cache_entry *ce)
2562	{
2563	/*
2564	* The only thing we care about in this function is to smudge the
2565	* falsely clean entry due to touch-update-touch race, so we leave
2566	* everything else as they are. We are called for entries whose
2567	* ce_stat_data.sd_mtime match the index file mtime.
2568	*
2569	* Note that this actually does not do much for gitlinks, for
2570	* which ce_match_stat_basic() always goes to the actual
2571	* contents. The caller checks with is_racy_timestamp() which
2572	* always says "no" for gitlinks, so we are not called for them ;-)
2573	*/
2574	struct stat st;
2575
2576	if (lstat(ce->name, &st) < 0)
2577	return;
2578	if (ce_match_stat_basic(ce, &st))
2579	return;
2580	if (ce_modified_check_fs(istate, ce, &st)) {
2581	/* This is "racily clean"; smudge it. Note that this
2582	* is a tricky code. At first glance, it may appear
2583	* that it can break with this sequence:
2584	*
2585	* $ echo xyzzy >frotz
2586	* $ git-update-index --add frotz
2587	* $ : >frotz
2588	* $ sleep 3
2589	* $ echo filfre >nitfol
2590	* $ git-update-index --add nitfol
2591	*
2592	* but it does not. When the second update-index runs,
2593	* it notices that the entry "frotz" has the same timestamp
2594	* as index, and if we were to smudge it by resetting its
2595	* size to zero here, then the object name recorded
2596	* in index is the 6-byte file but the cached stat information
2597	* becomes zero --- which would then match what we would
2598	* obtain from the filesystem next time we stat("frotz").
2599	*
2600	* However, the second update-index, before calling
2601	* this function, notices that the cached size is 6
2602	* bytes and what is on the filesystem is an empty
2603	* file, and never calls us, so the cached size information
2604	* for "frotz" stays 6 which does not match the filesystem.
2605	*/
2606	ce->ce_stat_data.sd_size = 0;
2607	}
2608	}
2609
2610	/* Copy miscellaneous fields but not the name */
2611	static void copy_cache_entry_to_ondisk(struct ondisk_cache_entry *ondisk,
2612	struct cache_entry *ce)
2613	{
2614	short flags;
2615	const unsigned hashsz = the_hash_algo->rawsz;
2616	uint16_t flagsp = (uint16_t )(ondisk->data + hashsz);
2617
2618	ondisk->ctime.sec = htonl(ce->ce_stat_data.sd_ctime.sec);
2619	ondisk->mtime.sec = htonl(ce->ce_stat_data.sd_mtime.sec);
2620	ondisk->ctime.nsec = htonl(ce->ce_stat_data.sd_ctime.nsec);
2621	ondisk->mtime.nsec = htonl(ce->ce_stat_data.sd_mtime.nsec);
2622	ondisk->dev = htonl(ce->ce_stat_data.sd_dev);
2623	ondisk->ino = htonl(ce->ce_stat_data.sd_ino);
2624	ondisk->mode = htonl(ce->ce_mode);
2625	ondisk->uid = htonl(ce->ce_stat_data.sd_uid);
2626	ondisk->gid = htonl(ce->ce_stat_data.sd_gid);
2627	ondisk->size = htonl(ce->ce_stat_data.sd_size);
2628	hashcpy(ondisk->data, ce->oid.hash, the_repository->hash_algo);
2629
2630	flags = ce->ce_flags & ~CE_NAMEMASK;
2631	flags \|= (ce_namelen(ce) >= CE_NAMEMASK ? CE_NAMEMASK : ce_namelen(ce));
2632	flagsp[0] = htons(flags);
2633	if (ce->ce_flags & CE_EXTENDED) {
2634	flagsp[1] = htons((ce->ce_flags & CE_EXTENDED_FLAGS) >> 16);
2635	}
2636	}
2637
2638	static int ce_write_entry(struct hashfile f, struct cache_entry ce,
2639	struct strbuf previous_name, struct ondisk_cache_entry ondisk)
2640	{
2641	int size;
2642	unsigned int saved_namelen;
2643	int stripped_name = 0;
2644	static unsigned char padding[8] = { 0x00 };
2645
2646	if (ce->ce_flags & CE_STRIP_NAME) {
2647	saved_namelen = ce_namelen(ce);
2648	ce->ce_namelen = 0;
2649	stripped_name = 1;
2650	}
2651
2652	size = offsetof(struct ondisk_cache_entry,data) + ondisk_data_size(ce->ce_flags, 0);
2653
2654	if (!previous_name) {
2655	int len = ce_namelen(ce);
2656	copy_cache_entry_to_ondisk(ondisk, ce);
2657	hashwrite(f, ondisk, size);
2658	hashwrite(f, ce->name, len);
2659	hashwrite(f, padding, align_padding_size(size, len));
2660	} else {
2661	int common, to_remove;
2662	uint8_t prefix_size;
2663	unsigned char to_remove_vi[16];
2664
2665	for (common = 0;
2666	(common < previous_name->len &&
2667	ce->name[common] &&
2668	ce->name[common] == previous_name->buf[common]);
2669	common++)
2670	; /* still matching */
2671	to_remove = previous_name->len - common;
2672	prefix_size = encode_varint(to_remove, to_remove_vi);
2673
2674	copy_cache_entry_to_ondisk(ondisk, ce);
2675	hashwrite(f, ondisk, size);
2676	hashwrite(f, to_remove_vi, prefix_size);
2677	hashwrite(f, ce->name + common, ce_namelen(ce) - common);
2678	hashwrite(f, padding, 1);
2679
2680	strbuf_splice(previous_name, common, to_remove,
2681	ce->name + common, ce_namelen(ce) - common);
2682	}
2683	if (stripped_name) {
2684	ce->ce_namelen = saved_namelen;
2685	ce->ce_flags &= ~CE_STRIP_NAME;
2686	}
2687
2688	return 0;
2689	}
2690
2691	/*
2692	* This function verifies if index_state has the correct sha1 of the
2693	* index file. Don't die if we have any other failure, just return 0.
2694	*/
2695	static int verify_index_from(const struct index_state istate, const char path)
2696	{
2697	int fd;
2698	ssize_t n;
2699	struct stat st;
2700	unsigned char hash[GIT_MAX_RAWSZ];
2701
2702	if (!istate->initialized)
2703	return 0;
2704
2705	fd = open(path, O_RDONLY);
2706	if (fd < 0)
2707	return 0;
2708
2709	if (fstat(fd, &st))
2710	goto out;
2711
2712	if (st.st_size < sizeof(struct cache_header) + the_hash_algo->rawsz)
2713	goto out;
2714
2715	n = pread_in_full(fd, hash, the_hash_algo->rawsz, st.st_size - the_hash_algo->rawsz);
2716	if (n != the_hash_algo->rawsz)
2717	goto out;
2718
2719	if (!hasheq(istate->oid.hash, hash, the_repository->hash_algo))
2720	goto out;
2721
2722	close(fd);
2723	return 1;
2724
2725	out:
2726	close(fd);
2727	return 0;
2728	}
2729
2730	static int repo_verify_index(struct repository *repo)
2731	{
2732	return verify_index_from(repo->index, repo->index_file);
2733	}
2734
2735	int has_racy_timestamp(struct index_state *istate)
2736	{
2737	int entries = istate->cache_nr;
2738	int i;
2739
2740	for (i = 0; i < entries; i++) {
2741	struct cache_entry *ce = istate->cache[i];
2742	if (is_racy_timestamp(istate, ce))
2743	return 1;
2744	}
2745	return 0;
2746	}
2747
2748	void repo_update_index_if_able(struct repository *repo,
2749	struct lock_file *lockfile)
2750	{
2751	if ((repo->index->cache_changed \|\|
2752	has_racy_timestamp(repo->index)) &&
2753	repo_verify_index(repo))
2754	write_locked_index(repo->index, lockfile, COMMIT_LOCK);
2755	else
2756	rollback_lock_file(lockfile);
2757	}
2758
2759	static int record_eoie(void)
2760	{
2761	int val;
2762
2763	if (!repo_config_get_bool(the_repository, "index.recordendofindexentries", &val))
2764	return val;
2765
2766	/*
2767	* As a convenience, the end of index entries extension
2768	* used for threading is written by default if the user
2769	* explicitly requested threaded index reads.
2770	*/
2771	return !repo_config_get_index_threads(the_repository, &val) && val != 1;
2772	}
2773
2774	static int record_ieot(void)
2775	{
2776	int val;
2777
2778	if (!repo_config_get_bool(the_repository, "index.recordoffsettable", &val))
2779	return val;
2780
2781	/*
2782	* As a convenience, the offset table used for threading is
2783	* written by default if the user explicitly requested
2784	* threaded index reads.
2785	*/
2786	return !repo_config_get_index_threads(the_repository, &val) && val != 1;
2787	}
2788
2789	enum write_extensions {
2790	WRITE_NO_EXTENSION = 0,
2791	WRITE_SPLIT_INDEX_EXTENSION = 1<<0,
2792	WRITE_CACHE_TREE_EXTENSION = 1<<1,
2793	WRITE_RESOLVE_UNDO_EXTENSION = 1<<2,
2794	WRITE_UNTRACKED_CACHE_EXTENSION = 1<<3,
2795	WRITE_FSMONITOR_EXTENSION = 1<<4,
2796	};
2797	#define WRITE_ALL_EXTENSIONS ((enum write_extensions)-1)
2798
2799	/*
2800	* On success, `tempfile` is closed. If it is the temporary file
2801	* of a `struct lock_file`, we will therefore effectively perform
2802	* a 'close_lock_file_gently()`. Since that is an implementation
2803	* detail of lockfiles, callers of `do_write_index()` should not
2804	* rely on it.
2805	*/
2806	static int do_write_index(struct index_state istate, struct tempfile tempfile,
2807	enum write_extensions write_extensions, unsigned flags)
2808	{
2809	uint64_t start = getnanotime();
2810	struct hashfile *f;
2811	struct git_hash_ctx *eoie_c = NULL;
2812	struct cache_header hdr;
2813	int i, err = 0, removed, extended, hdr_version;
2814	struct cache_entry **cache = istate->cache;
2815	int entries = istate->cache_nr;
2816	struct stat st;
2817	struct ondisk_cache_entry ondisk;
2818	struct strbuf previous_name_buf = STRBUF_INIT, *previous_name;
2819	int drop_cache_tree = istate->drop_cache_tree;
2820	off_t offset;
2821	int csum_fsync_flag;
2822	int ieot_entries = 1;
2823	struct index_entry_offset_table *ieot = NULL;
2824	struct repository *r = istate->repo;
2825	struct strbuf sb = STRBUF_INIT;
2826	int nr, nr_threads, ret;
2827
2828	f = hashfd(the_repository->hash_algo, tempfile->fd, tempfile->filename.buf);
2829
2830	prepare_repo_settings(r);
2831	f->skip_hash = r->settings.index_skip_hash;
2832
2833	for (i = removed = extended = 0; i < entries; i++) {
2834	if (cache[i]->ce_flags & CE_REMOVE)
2835	removed++;
2836
2837	/* reduce extended entries if possible */
2838	cache[i]->ce_flags &= ~CE_EXTENDED;
2839	if (cache[i]->ce_flags & CE_EXTENDED_FLAGS) {
2840	extended++;
2841	cache[i]->ce_flags \|= CE_EXTENDED;
2842	}
2843	}
2844
2845	if (!istate->version)
2846	istate->version = get_index_format_default(r);
2847
2848	/* demote version 3 to version 2 when the latter suffices */
2849	if (istate->version == 3 \|\| istate->version == 2)
2850	istate->version = extended ? 3 : 2;
2851
2852	hdr_version = istate->version;
2853
2854	hdr.hdr_signature = htonl(CACHE_SIGNATURE);
2855	hdr.hdr_version = htonl(hdr_version);
2856	hdr.hdr_entries = htonl(entries - removed);
2857
2858	hashwrite(f, &hdr, sizeof(hdr));
2859
2860	if (!HAVE_THREADS \|\| repo_config_get_index_threads(the_repository, &nr_threads))
2861	nr_threads = 1;
2862
2863	if (nr_threads != 1 && record_ieot()) {
2864	int ieot_blocks, cpus;
2865
2866	/*
2867	* ensure default number of ieot blocks maps evenly to the
2868	* default number of threads that will process them leaving
2869	* room for the thread to load the index extensions.
2870	*/
2871	if (!nr_threads) {
2872	ieot_blocks = istate->cache_nr / THREAD_COST;
2873	cpus = online_cpus();
2874	if (ieot_blocks > cpus - 1)
2875	ieot_blocks = cpus - 1;
2876	} else {
2877	ieot_blocks = nr_threads;
2878	if (ieot_blocks > istate->cache_nr)
2879	ieot_blocks = istate->cache_nr;
2880	}
2881
2882	/*
2883	* no reason to write out the IEOT extension if we don't
2884	* have enough blocks to utilize multi-threading
2885	*/
2886	if (ieot_blocks > 1) {
2887	ieot = xcalloc(1, sizeof(struct index_entry_offset_table)
2888	+ (ieot_blocks * sizeof(struct index_entry_offset)));
2889	ieot_entries = DIV_ROUND_UP(entries, ieot_blocks);
2890	}
2891	}
2892
2893	offset = hashfile_total(f);
2894
2895	nr = 0;
2896	previous_name = (hdr_version == 4) ? &previous_name_buf : NULL;
2897
2898	for (i = 0; i < entries; i++) {
2899	struct cache_entry *ce = cache[i];
2900	if (ce->ce_flags & CE_REMOVE)
2901	continue;
2902	if (!ce_uptodate(ce) && is_racy_timestamp(istate, ce))
2903	ce_smudge_racily_clean_entry(istate, ce);
2904	if (is_null_oid(&ce->oid)) {
2905	static const char msg[] = "cache entry has null sha1: %s";
2906	static int allow = -1;
2907
2908	if (allow < 0)
2909	allow = git_env_bool("GIT_ALLOW_NULL_SHA1", 0);
2910	if (allow)
2911	warning(msg, ce->name);
2912	else
2913	err = error(msg, ce->name);
2914
2915	drop_cache_tree = 1;
2916	}
2917	if (ieot && i && (i % ieot_entries == 0)) {
2918	ieot->entries[ieot->nr].nr = nr;
2919	ieot->entries[ieot->nr].offset = offset;
2920	ieot->nr++;
2921	/*
2922	* If we have a V4 index, set the first byte to an invalid
2923	* character to ensure there is nothing common with the previous
2924	* entry
2925	*/
2926	if (previous_name)
2927	previous_name->buf[0] = 0;
2928	nr = 0;
2929
2930	offset = hashfile_total(f);
2931	}
2932	if (ce_write_entry(f, ce, previous_name, (struct ondisk_cache_entry *)&ondisk) < 0)
2933	err = -1;
2934
2935	if (err)
2936	break;
2937	nr++;
2938	}
2939	if (ieot && nr) {
2940	ieot->entries[ieot->nr].nr = nr;
2941	ieot->entries[ieot->nr].offset = offset;
2942	ieot->nr++;
2943	}
2944	strbuf_release(&previous_name_buf);
2945
2946	if (err) {
2947	ret = err;
2948	goto out;
2949	}
2950
2951	offset = hashfile_total(f);
2952
2953	/*
2954	* The extension headers must be hashed on their own for the
2955	* EOIE extension. Create a hashfile here to compute that hash.
2956	*/
2957	if (offset && record_eoie()) {
2958	CALLOC_ARRAY(eoie_c, 1);
2959	the_hash_algo->init_fn(eoie_c);
2960	}
2961
2962	/*
2963	* Lets write out CACHE_EXT_INDEXENTRYOFFSETTABLE first so that we
2964	* can minimize the number of extensions we have to scan through to
2965	* find it during load. Write it out regardless of the
2966	* strip_extensions parameter as we need it when loading the shared
2967	* index.
2968	*/
2969	if (ieot) {
2970	strbuf_reset(&sb);
2971
2972	write_ieot_extension(&sb, ieot);
2973	err = write_index_ext_header(f, eoie_c, CACHE_EXT_INDEXENTRYOFFSETTABLE, sb.len) < 0;
2974	hashwrite(f, sb.buf, sb.len);
2975	if (err) {
2976	ret = -1;
2977	goto out;
2978	}
2979	}
2980
2981	if (write_extensions & WRITE_SPLIT_INDEX_EXTENSION &&
2982	istate->split_index) {
2983	strbuf_reset(&sb);
2984
2985	if (istate->sparse_index)
2986	die(_("cannot write split index for a sparse index"));
2987
2988	err = write_link_extension(&sb, istate) < 0 \|\|
2989	write_index_ext_header(f, eoie_c, CACHE_EXT_LINK,
2990	sb.len) < 0;
2991	hashwrite(f, sb.buf, sb.len);
2992	if (err) {
2993	ret = -1;
2994	goto out;
2995	}
2996	}
2997	if (write_extensions & WRITE_CACHE_TREE_EXTENSION &&
2998	!drop_cache_tree && istate->cache_tree) {
2999	strbuf_reset(&sb);
3000
3001	cache_tree_write(&sb, istate->cache_tree);
3002	err = write_index_ext_header(f, eoie_c, CACHE_EXT_TREE, sb.len) < 0;
3003	hashwrite(f, sb.buf, sb.len);
3004	if (err) {
3005	ret = -1;
3006	goto out;
3007	}
3008	}
3009	if (write_extensions & WRITE_RESOLVE_UNDO_EXTENSION &&
3010	istate->resolve_undo) {
3011	strbuf_reset(&sb);
3012
3013	resolve_undo_write(&sb, istate->resolve_undo, the_hash_algo);
3014	err = write_index_ext_header(f, eoie_c, CACHE_EXT_RESOLVE_UNDO,
3015	sb.len) < 0;
3016	hashwrite(f, sb.buf, sb.len);
3017	if (err) {
3018	ret = -1;
3019	goto out;
3020	}
3021	}
3022	if (write_extensions & WRITE_UNTRACKED_CACHE_EXTENSION &&
3023	istate->untracked) {
3024	strbuf_reset(&sb);
3025
3026	write_untracked_extension(&sb, istate->untracked);
3027	err = write_index_ext_header(f, eoie_c, CACHE_EXT_UNTRACKED,
3028	sb.len) < 0;
3029	hashwrite(f, sb.buf, sb.len);
3030	if (err) {
3031	ret = -1;
3032	goto out;
3033	}
3034	}
3035	if (write_extensions & WRITE_FSMONITOR_EXTENSION &&
3036	istate->fsmonitor_last_update) {
3037	strbuf_reset(&sb);
3038
3039	write_fsmonitor_extension(&sb, istate);
3040	err = write_index_ext_header(f, eoie_c, CACHE_EXT_FSMONITOR, sb.len) < 0;
3041	hashwrite(f, sb.buf, sb.len);
3042	if (err) {
3043	ret = -1;
3044	goto out;
3045	}
3046	}
3047	if (istate->sparse_index) {
3048	if (write_index_ext_header(f, eoie_c, CACHE_EXT_SPARSE_DIRECTORIES, 0) < 0) {
3049	ret = -1;
3050	goto out;
3051	}
3052	}
3053
3054	/*
3055	* CACHE_EXT_ENDOFINDEXENTRIES must be written as the last entry before the SHA1
3056	* so that it can be found and processed before all the index entries are
3057	* read. Write it out regardless of the strip_extensions parameter as we need it
3058	* when loading the shared index.
3059	*/
3060	if (eoie_c) {
3061	strbuf_reset(&sb);
3062
3063	write_eoie_extension(&sb, eoie_c, offset);
3064	err = write_index_ext_header(f, NULL, CACHE_EXT_ENDOFINDEXENTRIES, sb.len) < 0;
3065	hashwrite(f, sb.buf, sb.len);
3066	if (err) {
3067	ret = -1;
3068	goto out;
3069	}
3070	}
3071
3072	csum_fsync_flag = 0;
3073	if (!alternate_index_output && (flags & COMMIT_LOCK))
3074	csum_fsync_flag = CSUM_FSYNC;
3075
3076	finalize_hashfile(f, istate->oid.hash, FSYNC_COMPONENT_INDEX,
3077	CSUM_HASH_IN_STREAM \| csum_fsync_flag);
3078	f = NULL;
3079
3080	if (close_tempfile_gently(tempfile)) {
3081	ret = error(_("could not close '%s'"), get_tempfile_path(tempfile));
3082	goto out;
3083	}
3084	if (stat(get_tempfile_path(tempfile), &st)) {
3085	ret = -1;
3086	goto out;
3087	}
3088	istate->timestamp.sec = (unsigned int)st.st_mtime;
3089	istate->timestamp.nsec = ST_MTIME_NSEC(st);
3090	trace_performance_since(start, "write index, changed mask = %x", istate->cache_changed);
3091
3092	trace2_data_intmax("index", istate->repo, "write/version",
3093	istate->version);
3094	trace2_data_intmax("index", istate->repo, "write/cache_nr",
3095	istate->cache_nr);
3096
3097	ret = 0;
3098
3099	out:
3100	if (f)
3101	free_hashfile(f);
3102	strbuf_release(&sb);
3103	free(eoie_c);
3104	free(ieot);
3105	return ret;
3106	}
3107
3108	void set_alternate_index_output(const char *name)
3109	{
3110	alternate_index_output = name;
3111	}
3112
3113	static int commit_locked_index(struct lock_file *lk)
3114	{
3115	if (alternate_index_output)
3116	return commit_lock_file_to(lk, alternate_index_output);
3117	else
3118	return commit_lock_file(lk);
3119	}
3120
3121	static int do_write_locked_index(struct index_state *istate,
3122	struct lock_file *lock,
3123	unsigned flags,
3124	enum write_extensions write_extensions)
3125	{
3126	int ret;
3127	int was_full = istate->sparse_index == INDEX_EXPANDED;
3128
3129	ret = convert_to_sparse(istate, 0);
3130
3131	if (ret) {
3132	warning(_("failed to convert to a sparse-index"));
3133	return ret;
3134	}
3135
3136	trace2_region_enter_printf("index", "do_write_index", istate->repo,
3137	"%s", get_lock_file_path(lock));
3138	ret = do_write_index(istate, lock->tempfile, write_extensions, flags);
3139	trace2_region_leave_printf("index", "do_write_index", istate->repo,
3140	"%s", get_lock_file_path(lock));
3141
3142	if (was_full)
3143	ensure_full_index(istate);
3144
3145	if (ret)
3146	return ret;
3147	if (flags & COMMIT_LOCK)
3148	ret = commit_locked_index(lock);
3149	else
3150	ret = close_lock_file_gently(lock);
3151
3152	run_hooks_l(the_repository, "post-index-change",
3153	istate->updated_workdir ? "1" : "0",
3154	istate->updated_skipworktree ? "1" : "0", NULL);
3155	istate->updated_workdir = 0;
3156	istate->updated_skipworktree = 0;
3157
3158	return ret;
3159	}
3160
3161	static int write_split_index(struct index_state *istate,
3162	struct lock_file *lock,
3163	unsigned flags)
3164	{
3165	int ret;
3166	prepare_to_write_split_index(istate);
3167	ret = do_write_locked_index(istate, lock, flags, WRITE_ALL_EXTENSIONS);
3168	finish_writing_split_index(istate);
3169	return ret;
3170	}
3171
3172	static unsigned long get_shared_index_expire_date(void)
3173	{
3174	static unsigned long shared_index_expire_date;
3175	static int shared_index_expire_date_prepared;
3176
3177	if (!shared_index_expire_date_prepared) {
3178	const char *shared_index_expire = "2.weeks.ago";
3179	char *value = NULL;
3180
3181	repo_config_get_expiry(the_repository, "splitindex.sharedindexexpire",
3182	&value);
3183	if (value)
3184	shared_index_expire = value;
3185
3186	shared_index_expire_date = approxidate(shared_index_expire);
3187	shared_index_expire_date_prepared = 1;
3188
3189	free(value);
3190	}
3191
3192	return shared_index_expire_date;
3193	}
3194
3195	static int should_delete_shared_index(const char *shared_index_path)
3196	{
3197	struct stat st;
3198	unsigned long expiration;
3199
3200	/* Check timestamp */
3201	expiration = get_shared_index_expire_date();
3202	if (!expiration)
3203	return 0;
3204	if (stat(shared_index_path, &st))
3205	return error_errno(_("could not stat '%s'"), shared_index_path);
3206	if (st.st_mtime > expiration)
3207	return 0;
3208
3209	return 1;
3210	}
3211
3212	static int clean_shared_index_files(const char *current_hex)
3213	{
3214	struct dirent *de;
3215	DIR *dir = opendir(repo_get_git_dir(the_repository));
3216
3217	if (!dir)
3218	return error_errno(_("unable to open git dir: %s"),
3219	repo_get_git_dir(the_repository));
3220
3221	while ((de = readdir(dir)) != NULL) {
3222	const char *sha1_hex;
3223	char *shared_index_path;
3224	if (!skip_prefix(de->d_name, "sharedindex.", &sha1_hex))
3225	continue;
3226	if (!strcmp(sha1_hex, current_hex))
3227	continue;
3228
3229	shared_index_path = repo_git_path(the_repository, "%s", de->d_name);
3230	if (should_delete_shared_index(shared_index_path) > 0 &&
3231	unlink(shared_index_path))
3232	warning_errno(_("unable to unlink: %s"), shared_index_path);
3233
3234	free(shared_index_path);
3235	}
3236	closedir(dir);
3237
3238	return 0;
3239	}
3240
3241	static int write_shared_index(struct index_state *istate,
3242	struct tempfile **temp, unsigned flags)
3243	{
3244	struct split_index *si = istate->split_index;
3245	int ret, was_full = !istate->sparse_index;
3246	char *path;
3247
3248	move_cache_to_base_index(istate);
3249	convert_to_sparse(istate, 0);
3250
3251	trace2_region_enter_printf("index", "shared/do_write_index",
3252	the_repository, "%s", get_tempfile_path(*temp));
3253	ret = do_write_index(si->base, *temp, WRITE_NO_EXTENSION, flags);
3254	trace2_region_leave_printf("index", "shared/do_write_index",
3255	the_repository, "%s", get_tempfile_path(*temp));
3256
3257	if (was_full)
3258	ensure_full_index(istate);
3259
3260	if (ret)
3261	return ret;
3262	ret = adjust_shared_perm(the_repository, get_tempfile_path(*temp));
3263	if (ret) {
3264	error(_("cannot fix permission bits on '%s'"), get_tempfile_path(*temp));
3265	return ret;
3266	}
3267
3268	path = repo_git_path(the_repository, "sharedindex.%s", oid_to_hex(&si->base->oid));
3269	ret = rename_tempfile(temp, path);
3270	if (!ret) {
3271	oidcpy(&si->base_oid, &si->base->oid);
3272	clean_shared_index_files(oid_to_hex(&si->base->oid));
3273	}
3274
3275	free(path);
3276	return ret;
3277	}
3278
3279	static const int default_max_percent_split_change = 20;
3280
3281	static int too_many_not_shared_entries(struct index_state *istate)
3282	{
3283	int i, not_shared = 0;
3284	int max_split = repo_config_get_max_percent_split_change(the_repository);
3285
3286	switch (max_split) {
3287	case -1:
3288	/* not or badly configured: use the default value */
3289	max_split = default_max_percent_split_change;
3290	break;
3291	case 0:
3292	return 1; /* 0% means always write a new shared index */
3293	case 100:
3294	return 0; /* 100% means never write a new shared index */
3295	default:
3296	break; /* just use the configured value */
3297	}
3298
3299	/* Count not shared entries */
3300	for (i = 0; i < istate->cache_nr; i++) {
3301	struct cache_entry *ce = istate->cache[i];
3302	if (!ce->index)
3303	not_shared++;
3304	}
3305
3306	return (int64_t)istate->cache_nr * max_split < (int64_t)not_shared * 100;
3307	}
3308
3309	int write_locked_index(struct index_state istate, struct lock_file lock,
3310	unsigned flags)
3311	{
3312	int new_shared_index, ret, test_split_index_env;
3313	struct split_index *si = istate->split_index;
3314
3315	if (git_env_bool("GIT_TEST_CHECK_CACHE_TREE", 0) &&
3316	cache_tree_verify(the_repository, istate) < 0)
3317	return -1;
3318
3319	if ((flags & SKIP_IF_UNCHANGED) && !istate->cache_changed) {
3320	if (flags & COMMIT_LOCK)
3321	rollback_lock_file(lock);
3322	return 0;
3323	}
3324
3325	if (istate->fsmonitor_last_update)
3326	fill_fsmonitor_bitmap(istate);
3327
3328	test_split_index_env = git_env_bool("GIT_TEST_SPLIT_INDEX", 0);
3329
3330	if ((!si && !test_split_index_env) \|\|
3331	alternate_index_output \|\|
3332	(istate->cache_changed & ~EXTMASK)) {
3333	ret = do_write_locked_index(istate, lock, flags,
3334	~WRITE_SPLIT_INDEX_EXTENSION);
3335	goto out;
3336	}
3337
3338	if (test_split_index_env) {
3339	if (!si) {
3340	si = init_split_index(istate);
3341	istate->cache_changed \|= SPLIT_INDEX_ORDERED;
3342	} else {
3343	int v = si->base_oid.hash[0];
3344	if ((v & 15) < 6)
3345	istate->cache_changed \|= SPLIT_INDEX_ORDERED;
3346	}
3347	}
3348	if (too_many_not_shared_entries(istate))
3349	istate->cache_changed \|= SPLIT_INDEX_ORDERED;
3350
3351	new_shared_index = istate->cache_changed & SPLIT_INDEX_ORDERED;
3352
3353	if (new_shared_index) {
3354	struct tempfile *temp;
3355	int saved_errno;
3356	char *path;
3357
3358	/* Same initial permissions as the main .git/index file */
3359	path = repo_git_path(the_repository, "sharedindex_XXXXXX");
3360	temp = mks_tempfile_sm(path, 0, 0666);
3361	free(path);
3362	if (!temp) {
3363	ret = do_write_locked_index(istate, lock, flags,
3364	~WRITE_SPLIT_INDEX_EXTENSION);
3365	goto out;
3366	}
3367	ret = write_shared_index(istate, &temp, flags);
3368
3369	saved_errno = errno;
3370	if (is_tempfile_active(temp))
3371	delete_tempfile(&temp);
3372	errno = saved_errno;
3373
3374	if (ret)
3375	goto out;
3376	}
3377
3378	ret = write_split_index(istate, lock, flags);
3379
3380	/* Freshen the shared index only if the split-index was written */
3381	if (!ret && !new_shared_index && !is_null_oid(&si->base_oid)) {
3382	char *shared_index = repo_git_path(the_repository, "sharedindex.%s",
3383	oid_to_hex(&si->base_oid));
3384	freshen_shared_index(shared_index, 1);
3385	free(shared_index);
3386	}
3387
3388	out:
3389	if (flags & COMMIT_LOCK)
3390	rollback_lock_file(lock);
3391	return ret;
3392	}
3393
3394	/*
3395	* Read the index file that is potentially unmerged into given
3396	* index_state, dropping any unmerged entries to stage #0 (potentially
3397	* resulting in a path appearing as both a file and a directory in the
3398	* index; the caller is responsible to clear out the extra entries
3399	* before writing the index to a tree). Returns true if the index is
3400	* unmerged. Callers who want to refuse to work from an unmerged
3401	* state can call this and check its return value, instead of calling
3402	* read_cache().
3403	*/
3404	int repo_read_index_unmerged(struct repository *repo)
3405	{
3406	struct index_state *istate;
3407	int i;
3408	int unmerged = 0;
3409
3410	repo_read_index(repo);
3411	istate = repo->index;
3412	for (i = 0; i < istate->cache_nr; i++) {
3413	struct cache_entry *ce = istate->cache[i];
3414	struct cache_entry *new_ce;
3415	int len;
3416
3417	if (!ce_stage(ce))
3418	continue;
3419	unmerged = 1;
3420	len = ce_namelen(ce);
3421	new_ce = make_empty_cache_entry(istate, len);
3422	memcpy(new_ce->name, ce->name, len);
3423	new_ce->ce_flags = create_ce_flags(0) \| CE_CONFLICTED;
3424	new_ce->ce_namelen = len;
3425	new_ce->ce_mode = ce->ce_mode;
3426	if (add_index_entry(istate, new_ce, ADD_CACHE_SKIP_DFCHECK))
3427	return error(_("%s: cannot drop to stage #0"),
3428	new_ce->name);
3429	}
3430	return unmerged;
3431	}
3432
3433	/*
3434	* Returns 1 if the path is an "other" path with respect to
3435	* the index; that is, the path is not mentioned in the index at all,
3436	* either as a file, a directory with some files in the index,
3437	* or as an unmerged entry.
3438	*
3439	* We helpfully remove a trailing "/" from directories so that
3440	* the output of read_directory can be used as-is.
3441	*/
3442	int index_name_is_other(struct index_state istate, const char name,
3443	int namelen)
3444	{
3445	int pos;
3446	if (namelen && name[namelen - 1] == '/')
3447	namelen--;
3448	pos = index_name_pos(istate, name, namelen);
3449	if (0 <= pos)
3450	return 0; /* exact match */
3451	pos = -pos - 1;
3452	if (pos < istate->cache_nr) {
3453	struct cache_entry *ce = istate->cache[pos];
3454	if (ce_namelen(ce) == namelen &&
3455	!memcmp(ce->name, name, namelen))
3456	return 0; /* Yup, this one exists unmerged */
3457	}
3458	return 1;
3459	}
3460
3461	void read_blob_data_from_index(struct index_state istate,
3462	const char path, unsigned long size)
3463	{
3464	int pos, len;
3465	unsigned long sz;
3466	enum object_type type;
3467	void *data;
3468
3469	len = strlen(path);
3470	pos = index_name_pos(istate, path, len);
3471	if (pos < 0) {
3472	/*
3473	* We might be in the middle of a merge, in which
3474	* case we would read stage #2 (ours).
3475	*/
3476	int i;
3477	for (i = -pos - 1;
3478	(pos < 0 && i < istate->cache_nr &&
3479	!strcmp(istate->cache[i]->name, path));
3480	i++)
3481	if (ce_stage(istate->cache[i]) == 2)
3482	pos = i;
3483	}
3484	if (pos < 0)
3485	return NULL;
3486	data = odb_read_object(the_repository->objects, &istate->cache[pos]->oid,
3487	&type, &sz);
3488	if (!data \|\| type != OBJ_BLOB) {
3489	free(data);
3490	return NULL;
3491	}
3492	if (size)
3493	*size = sz;
3494	return data;
3495	}
3496
3497	void move_index_extensions(struct index_state dst, struct index_state src)
3498	{
3499	dst->untracked = src->untracked;
3500	src->untracked = NULL;
3501	dst->cache_tree = src->cache_tree;
3502	src->cache_tree = NULL;
3503	}
3504
3505	struct cache_entry dup_cache_entry(const struct cache_entry ce,
3506	struct index_state *istate)
3507	{
3508	unsigned int size = ce_size(ce);
3509	int mem_pool_allocated;
3510	struct cache_entry *new_entry = make_empty_cache_entry(istate, ce_namelen(ce));
3511	mem_pool_allocated = new_entry->mem_pool_allocated;
3512
3513	memcpy(new_entry, ce, size);
3514	new_entry->mem_pool_allocated = mem_pool_allocated;
3515	return new_entry;
3516	}
3517
3518	void discard_cache_entry(struct cache_entry *ce)
3519	{
3520	if (ce && should_validate_cache_entries())
3521	memset(ce, 0xCD, cache_entry_size(ce->ce_namelen));
3522
3523	if (ce && ce->mem_pool_allocated)
3524	return;
3525
3526	free(ce);
3527	}
3528
3529	int should_validate_cache_entries(void)
3530	{
3531	static int validate_index_cache_entries = -1;
3532
3533	if (validate_index_cache_entries < 0) {
3534	if (getenv("GIT_TEST_VALIDATE_INDEX_CACHE_ENTRIES"))
3535	validate_index_cache_entries = 1;
3536	else
3537	validate_index_cache_entries = 0;
3538	}
3539
3540	return validate_index_cache_entries;
3541	}
3542
3543	#define EOIE_SIZE (4 + GIT_SHA1_RAWSZ) /* <4-byte offset> + <20-byte hash> */
3544	#define EOIE_SIZE_WITH_HEADER (4 + 4 + EOIE_SIZE) /* <4-byte signature> + <4-byte length> + EOIE_SIZE */
3545
3546	static size_t read_eoie_extension(const char *mmap, size_t mmap_size)
3547	{
3548	/*
3549	* The end of index entries (EOIE) extension is guaranteed to be last
3550	* so that it can be found by scanning backwards from the EOF.
3551	*
3552	* "EOIE"
3553	* <4-byte length>
3554	* <4-byte offset>
3555	* <20-byte hash>
3556	*/
3557	const char index, eoie;
3558	uint32_t extsize;
3559	size_t offset, src_offset;
3560	unsigned char hash[GIT_MAX_RAWSZ];
3561	struct git_hash_ctx c;
3562
3563	/* ensure we have an index big enough to contain an EOIE extension */
3564	if (mmap_size < sizeof(struct cache_header) + EOIE_SIZE_WITH_HEADER + the_hash_algo->rawsz)
3565	return 0;
3566
3567	/* validate the extension signature */
3568	index = eoie = mmap + mmap_size - EOIE_SIZE_WITH_HEADER - the_hash_algo->rawsz;
3569	if (CACHE_EXT(index) != CACHE_EXT_ENDOFINDEXENTRIES)
3570	return 0;
3571	index += sizeof(uint32_t);
3572
3573	/* validate the extension size */
3574	extsize = get_be32(index);
3575	if (extsize != EOIE_SIZE)
3576	return 0;
3577	index += sizeof(uint32_t);
3578
3579	/*
3580	* Validate the offset we're going to look for the first extension
3581	* signature is after the index header and before the eoie extension.
3582	*/
3583	offset = get_be32(index);
3584	if (mmap + offset < mmap + sizeof(struct cache_header))
3585	return 0;
3586	if (mmap + offset >= eoie)
3587	return 0;
3588	index += sizeof(uint32_t);
3589
3590	/*
3591	* The hash is computed over extension types and their sizes (but not
3592	* their contents). E.g. if we have "TREE" extension that is N-bytes
3593	* long, "REUC" extension that is M-bytes long, followed by "EOIE",
3594	* then the hash would be:
3595	*
3596	* SHA-1("TREE" + <binary representation of N> +
3597	* "REUC" + <binary representation of M>)
3598	*/
3599	src_offset = offset;
3600	the_hash_algo->init_fn(&c);
3601	while (src_offset < mmap_size - the_hash_algo->rawsz - EOIE_SIZE_WITH_HEADER) {
3602	/* After an array of active_nr index entries,
3603	* there can be arbitrary number of extended
3604	* sections, each of which is prefixed with
3605	* extension name (4-byte) and section length
3606	* in 4-byte network byte order.
3607	*/
3608	uint32_t extsize;
3609	memcpy(&extsize, mmap + src_offset + 4, 4);
3610	extsize = ntohl(extsize);
3611
3612	/* verify the extension size isn't so large it will wrap around */
3613	if (src_offset + 8 + extsize < src_offset)
3614	return 0;
3615
3616	git_hash_update(&c, mmap + src_offset, 8);
3617
3618	src_offset += 8;
3619	src_offset += extsize;
3620	}
3621	git_hash_final(hash, &c);
3622	if (!hasheq(hash, (const unsigned char *)index, the_repository->hash_algo))
3623	return 0;
3624
3625	/* Validate that the extension offsets returned us back to the eoie extension. */
3626	if (src_offset != mmap_size - the_hash_algo->rawsz - EOIE_SIZE_WITH_HEADER)
3627	return 0;
3628
3629	return offset;
3630	}
3631
3632	static void write_eoie_extension(struct strbuf sb, struct git_hash_ctx eoie_context, size_t offset)
3633	{
3634	uint32_t buffer;
3635	unsigned char hash[GIT_MAX_RAWSZ];
3636
3637	/* offset */
3638	put_be32(&buffer, offset);
3639	strbuf_add(sb, &buffer, sizeof(uint32_t));
3640
3641	/* hash */
3642	git_hash_final(hash, eoie_context);
3643	strbuf_add(sb, hash, the_hash_algo->rawsz);
3644	}
3645
3646	#define IEOT_VERSION (1)
3647
3648	static struct index_entry_offset_table read_ieot_extension(const char mmap, size_t mmap_size, size_t offset)
3649	{
3650	const char *index = NULL;
3651	uint32_t extsize, ext_version;
3652	struct index_entry_offset_table *ieot;
3653	int i, nr;
3654
3655	/* find the IEOT extension */
3656	if (!offset)
3657	return NULL;
3658	while (offset <= mmap_size - the_hash_algo->rawsz - 8) {
3659	extsize = get_be32(mmap + offset + 4);
3660	if (CACHE_EXT((mmap + offset)) == CACHE_EXT_INDEXENTRYOFFSETTABLE) {
3661	index = mmap + offset + 4 + 4;
3662	break;
3663	}
3664	offset += 8;
3665	offset += extsize;
3666	}
3667	if (!index)
3668	return NULL;
3669
3670	/* validate the version is IEOT_VERSION */
3671	ext_version = get_be32(index);
3672	if (ext_version != IEOT_VERSION) {
3673	error("invalid IEOT version %d", ext_version);
3674	return NULL;
3675	}
3676	index += sizeof(uint32_t);
3677
3678	/* extension size - version bytes / bytes per entry */
3679	nr = (extsize - sizeof(uint32_t)) / (sizeof(uint32_t) + sizeof(uint32_t));
3680	if (!nr) {
3681	error("invalid number of IEOT entries %d", nr);
3682	return NULL;
3683	}
3684	ieot = xmalloc(sizeof(struct index_entry_offset_table)
3685	+ (nr * sizeof(struct index_entry_offset)));
3686	ieot->nr = nr;
3687	for (i = 0; i < nr; i++) {
3688	ieot->entries[i].offset = get_be32(index);
3689	index += sizeof(uint32_t);
3690	ieot->entries[i].nr = get_be32(index);
3691	index += sizeof(uint32_t);
3692	}
3693
3694	return ieot;
3695	}
3696
3697	static void write_ieot_extension(struct strbuf sb, struct index_entry_offset_table ieot)
3698	{
3699	uint32_t buffer;
3700	int i;
3701
3702	/* version */
3703	put_be32(&buffer, IEOT_VERSION);
3704	strbuf_add(sb, &buffer, sizeof(uint32_t));
3705
3706	/* ieot */
3707	for (i = 0; i < ieot->nr; i++) {
3708
3709	/* offset */
3710	put_be32(&buffer, ieot->entries[i].offset);
3711	strbuf_add(sb, &buffer, sizeof(uint32_t));
3712
3713	/* count */
3714	put_be32(&buffer, ieot->entries[i].nr);
3715	strbuf_add(sb, &buffer, sizeof(uint32_t));
3716	}
3717	}
3718
3719	void prefetch_cache_entries(const struct index_state *istate,
3720	must_prefetch_predicate must_prefetch)
3721	{
3722	int i;
3723	struct oid_array to_fetch = OID_ARRAY_INIT;
3724
3725	for (i = 0; i < istate->cache_nr; i++) {
3726	struct cache_entry *ce = istate->cache[i];
3727
3728	if (S_ISGITLINK(ce->ce_mode) \|\| !must_prefetch(ce))
3729	continue;
3730	if (!odb_read_object_info_extended(the_repository->objects,
3731	&ce->oid, NULL,
3732	OBJECT_INFO_FOR_PREFETCH))
3733	continue;
3734	oid_array_append(&to_fetch, &ce->oid);
3735	}
3736	promisor_remote_get_direct(the_repository,
3737	to_fetch.oid, to_fetch.nr);
3738	oid_array_clear(&to_fetch);
3739	}
3740
3741	static int read_one_entry_opt(struct index_state *istate,
3742	const struct object_id *oid,
3743	struct strbuf *base,
3744	const char *pathname,
3745	unsigned mode, int opt)
3746	{
3747	int len;
3748	struct cache_entry *ce;
3749
3750	if (S_ISDIR(mode))
3751	return READ_TREE_RECURSIVE;
3752
3753	len = strlen(pathname);
3754	ce = make_empty_cache_entry(istate, base->len + len);
3755
3756	ce->ce_mode = create_ce_mode(mode);
3757	ce->ce_flags = create_ce_flags(1);
3758	ce->ce_namelen = base->len + len;
3759	memcpy(ce->name, base->buf, base->len);
3760	memcpy(ce->name + base->len, pathname, len+1);
3761	oidcpy(&ce->oid, oid);
3762	return add_index_entry(istate, ce, opt);
3763	}
3764
3765	static int read_one_entry(const struct object_id oid, struct strbuf base,
3766	const char *pathname, unsigned mode,
3767	void *context)
3768	{
3769	struct index_state *istate = context;
3770	return read_one_entry_opt(istate, oid, base, pathname,
3771	mode,
3772	ADD_CACHE_OK_TO_ADD\|ADD_CACHE_SKIP_DFCHECK);
3773	}
3774
3775	/*
3776	* This is used when the caller knows there is no existing entries at
3777	* the stage that will conflict with the entry being added.
3778	*/
3779	static int read_one_entry_quick(const struct object_id oid, struct strbuf base,
3780	const char *pathname, unsigned mode,
3781	void *context)
3782	{
3783	struct index_state *istate = context;
3784	return read_one_entry_opt(istate, oid, base, pathname,
3785	mode, ADD_CACHE_JUST_APPEND);
3786	}
3787
3788	/*
3789	* Read the tree specified with --with-tree option
3790	* (typically, HEAD) into stage #1 and then
3791	* squash them down to stage #0. This is used for
3792	* --error-unmatch to list and check the path patterns
3793	* that were given from the command line. We are not
3794	* going to write this index out.
3795	*/
3796	void overlay_tree_on_index(struct index_state *istate,
3797	const char tree_name, const char prefix)
3798	{
3799	struct tree *tree;
3800	struct object_id oid;
3801	struct pathspec pathspec;
3802	struct cache_entry *last_stage0 = NULL;
3803	int i;
3804	read_tree_fn_t fn = NULL;
3805	int err;
3806
3807	if (repo_get_oid(the_repository, tree_name, &oid))
3808	die("tree-ish %s not found.", tree_name);
3809	tree = repo_parse_tree_indirect(the_repository, &oid);
3810	if (!tree)
3811	die("bad tree-ish %s", tree_name);
3812
3813	/* Hoist the unmerged entries up to stage #3 to make room */
3814	/* TODO: audit for interaction with sparse-index. */
3815	ensure_full_index(istate);
3816	for (i = 0; i < istate->cache_nr; i++) {
3817	struct cache_entry *ce = istate->cache[i];
3818	if (!ce_stage(ce))
3819	continue;
3820	ce->ce_flags \|= CE_STAGEMASK;
3821	}
3822
3823	if (prefix) {
3824	static const char *(matchbuf[1]);
3825	matchbuf[0] = NULL;
3826	parse_pathspec(&pathspec, PATHSPEC_ALL_MAGIC,
3827	PATHSPEC_PREFER_CWD, prefix, matchbuf);
3828	} else
3829	memset(&pathspec, 0, sizeof(pathspec));
3830
3831	/*
3832	* See if we have cache entry at the stage. If so,
3833	* do it the original slow way, otherwise, append and then
3834	* sort at the end.
3835	*/
3836	for (i = 0; !fn && i < istate->cache_nr; i++) {
3837	const struct cache_entry *ce = istate->cache[i];
3838	if (ce_stage(ce) == 1)
3839	fn = read_one_entry;
3840	}
3841
3842	if (!fn)
3843	fn = read_one_entry_quick;
3844	err = read_tree(the_repository, tree, &pathspec, fn, istate);
3845	clear_pathspec(&pathspec);
3846	if (err)
3847	die("unable to read tree entries %s", tree_name);
3848
3849	/*
3850	* Sort the cache entry -- we need to nuke the cache tree, though.
3851	*/
3852	if (fn == read_one_entry_quick) {
3853	cache_tree_free(&istate->cache_tree);
3854	QSORT(istate->cache, istate->cache_nr, cmp_cache_name_compare);
3855	}
3856
3857	for (i = 0; i < istate->cache_nr; i++) {
3858	struct cache_entry *ce = istate->cache[i];
3859	switch (ce_stage(ce)) {
3860	case 0:
3861	last_stage0 = ce;
3862	/* fallthru */
3863	default:
3864	continue;
3865	case 1:
3866	/*
3867	* If there is stage #0 entry for this, we do not
3868	* need to show it. We use CE_UPDATE bit to mark
3869	* such an entry.
3870	*/
3871	if (last_stage0 &&
3872	!strcmp(last_stage0->name, ce->name))
3873	ce->ce_flags \|= CE_UPDATE;
3874	}
3875	}
3876	}
3877
3878	struct update_callback_data {
3879	struct index_state *index;
3880	struct repository *repo;
3881	struct pathspec *pathspec;
3882	int include_sparse;
3883	int flags;
3884	int add_errors;
3885	int ignored_too;
3886	};
3887
3888	static int fix_unmerged_status(struct diff_filepair *p,
3889	struct update_callback_data *data)
3890	{
3891	if (p->status != DIFF_STATUS_UNMERGED)
3892	return p->status;
3893	if (!(data->flags & ADD_CACHE_IGNORE_REMOVAL) && !p->two->mode)
3894	/*
3895	* This is not an explicit add request, and the
3896	* path is missing from the working tree (deleted)
3897	*/
3898	return DIFF_STATUS_DELETED;
3899	else
3900	/*
3901	* Either an explicit add request, or path exists
3902	* in the working tree. An attempt to explicitly
3903	* add a path that does not exist in the working tree
3904	* will be caught as an error by the caller immediately.
3905	*/
3906	return DIFF_STATUS_MODIFIED;
3907	}
3908
3909	static int skip_submodule(const char *path,
3910	struct repository *repo,
3911	struct pathspec *pathspec,
3912	int ignored_too)
3913	{
3914	struct stat st;
3915	const struct submodule *sub;
3916	int pathspec_matches = 0;
3917	int ps_i;
3918	char *norm_pathspec = NULL;
3919
3920	/* Only consider if path is a directory */
3921	if (lstat(path, &st) \|\| !S_ISDIR(st.st_mode))
3922	return 0;
3923
3924	/* Check if it's a submodule with ignore=all */
3925	sub = submodule_from_path(repo, null_oid(the_hash_algo), path);
3926	if (!sub \|\| !sub->name \|\| !sub->ignore \|\| strcmp(sub->ignore, "all"))
3927	return 0;
3928
3929	trace_printf("ignore=all: %s\n", path);
3930	trace_printf("pathspec %s\n", (pathspec && pathspec->nr)
3931	? "has pathspec"
3932	: "no pathspec");
3933
3934	/* Check if submodule path is explicitly mentioned in pathspec */
3935	if (pathspec) {
3936	for (ps_i = 0; ps_i < pathspec->nr; ps_i++) {
3937	const char *m = pathspec->items[ps_i].match;
3938	if (!m)
3939	continue;
3940	norm_pathspec = xstrdup(m);
3941	strip_dir_trailing_slashes(norm_pathspec);
3942	if (!strcmp(path, norm_pathspec)) {
3943	pathspec_matches = 1;
3944	FREE_AND_NULL(norm_pathspec);
3945	break;
3946	}
3947	FREE_AND_NULL(norm_pathspec);
3948	}
3949	}
3950
3951	/* If explicitly matched and forced, allow adding */
3952	if (pathspec_matches) {
3953	if (ignored_too && ignored_too > 0) {
3954	trace_printf("Add submodule due to --force: %s\n", path);
3955	return 0;
3956	} else {
3957	advise_if_enabled(ADVICE_ADD_IGNORED_FILE,
3958	_("Skipping submodule due to ignore=all: %s\n"
3959	"Use --force if you really want to add the submodule."), path);
3960	return 1;
3961	}
3962	}
3963
3964	/* No explicit pathspec match -> skip silently */
3965	trace_printf("Pathspec to submodule does not match explicitly: %s\n", path);
3966	return 1;
3967	}
3968
3969	static void update_callback(struct diff_queue_struct *q,
3970	struct diff_options opt UNUSED, void cbdata)
3971	{
3972	int i;
3973	struct update_callback_data *data = cbdata;
3974
3975	for (i = 0; i < q->nr; i++) {
3976	struct diff_filepair *p = q->queue[i];
3977	const char *path = p->one->path;
3978
3979	if (!data->include_sparse &&
3980	!path_in_sparse_checkout(path, data->index))
3981	continue;
3982
3983	switch (fix_unmerged_status(p, data)) {
3984	default:
3985	die(_("unexpected diff status %c"), p->status);
3986	case DIFF_STATUS_MODIFIED:
3987	case DIFF_STATUS_TYPE_CHANGED:
3988	if (skip_submodule(path, data->repo,
3989	data->pathspec,
3990	data->ignored_too))
3991	continue;
3992
3993	if (add_file_to_index(data->index, path, data->flags)) {
3994	if (!(data->flags & ADD_CACHE_IGNORE_ERRORS))
3995	die(_("updating files failed"));
3996	data->add_errors++;
3997	}
3998	break;
3999	case DIFF_STATUS_DELETED:
4000	if (data->flags & ADD_CACHE_IGNORE_REMOVAL)
4001	break;
4002	if (!(data->flags & ADD_CACHE_PRETEND))
4003	remove_file_from_index(data->index, path);
4004	if (data->flags & (ADD_CACHE_PRETEND\|ADD_CACHE_VERBOSE))
4005	printf(_("remove '%s'\n"), path);
4006	break;
4007	}
4008	}
4009	}
4010
4011	int add_files_to_cache(struct repository repo, const char prefix,
4012	const struct pathspec pathspec, char ps_matched,
4013	int include_sparse, int flags, int ignored_too )
4014	{
4015	struct odb_transaction *transaction;
4016	struct update_callback_data data;
4017	struct rev_info rev;
4018
4019	memset(&data, 0, sizeof(data));
4020	data.index = repo->index;
4021	data.include_sparse = include_sparse;
4022	data.flags = flags;
4023	data.repo = repo;
4024	data.ignored_too = ignored_too;
4025	data.pathspec = (struct pathspec *)pathspec;
4026
4027	repo_init_revisions(repo, &rev, prefix);
4028	setup_revisions(0, NULL, &rev, NULL);
4029	if (pathspec) {
4030	copy_pathspec(&rev.prune_data, pathspec);
4031	rev.ps_matched = ps_matched;
4032	}
4033	rev.diffopt.output_format = DIFF_FORMAT_CALLBACK;
4034	rev.diffopt.format_callback = update_callback;
4035	rev.diffopt.format_callback_data = &data;
4036	rev.diffopt.flags.override_submodule_config = 1;
4037	rev.diffopt.detect_rename = 0; /* staging worktree changes does not need renames */
4038	rev.max_count = 0; /* do not compare unmerged paths with stage #2 */
4039
4040	/*
4041	* Use an ODB transaction to optimize adding multiple objects.
4042	* This function is invoked from commands other than 'add', which
4043	* may not have their own transaction active.
4044	*/
4045	transaction = odb_transaction_begin(repo->objects);
4046	run_diff_files(&rev, DIFF_RACY_IS_MODIFIED);
4047	odb_transaction_commit(transaction);
4048
4049	release_revisions(&rev);
4050	return !!data.add_errors;
4051	}