setup.c · leroysheep/Socializer · siGit Code & Deploy

seen

bisect jch maint master next seen test todo

c 2,955 lines 81.6 KB

Raw

1	#define DISABLE_SIGN_COMPARE_WARNINGS
2
3	#include "git-compat-util.h"
4	#include "abspath.h"
5	#include "copy.h"
6	#include "environment.h"
7	#include "exec-cmd.h"
8	#include "gettext.h"
9	#include "hex.h"
10	#include "object-file.h"
11	#include "object-name.h"
12	#include "refs.h"
13	#include "repository.h"
14	#include "config.h"
15	#include "dir.h"
16	#include "setup.h"
17	#include "shallow.h"
18	#include "string-list.h"
19	#include "strvec.h"
20	#include "chdir-notify.h"
21	#include "path.h"
22	#include "quote.h"
23	#include "trace.h"
24	#include "trace2.h"
25	#include "worktree.h"
26
27	enum allowed_bare_repo {
28	ALLOWED_BARE_REPO_EXPLICIT = 0,
29	ALLOWED_BARE_REPO_ALL,
30	};
31
32	static struct startup_info the_startup_info;
33	struct startup_info *startup_info = &the_startup_info;
34	const char *tmp_original_cwd;
35
36	/*
37	* The input parameter must contain an absolute path, and it must already be
38	* normalized.
39	*
40	* Find the part of an absolute path that lies inside the work tree by
41	* dereferencing symlinks outside the work tree, for example:
42	* /dir1/repo/dir2/file (work tree is /dir1/repo) -> dir2/file
43	* /dir/file (work tree is /) -> dir/file
44	* /dir/symlink1/symlink2 (symlink1 points to work tree) -> symlink2
45	* /dir/repolink/file (repolink points to /dir/repo) -> file
46	* /dir/repo (exactly equal to work tree) -> (empty string)
47	*/
48	static int abspath_part_inside_repo(struct repository repo, char path)
49	{
50	size_t len;
51	size_t wtlen;
52	char *path0;
53	int off;
54	const char *work_tree = precompose_string_if_needed(repo_get_work_tree(repo));
55	struct strbuf realpath = STRBUF_INIT;
56
57	if (!work_tree)
58	return -1;
59	wtlen = strlen(work_tree);
60	len = strlen(path);
61	off = offset_1st_component(path);
62
63	/* check if work tree is already the prefix */
64	if (wtlen <= len && !fspathncmp(path, work_tree, wtlen)) {
65	if (path[wtlen] == '/') {
66	memmove(path, path + wtlen + 1, len - wtlen);
67	return 0;
68	} else if (path[wtlen - 1] == '/' \|\| path[wtlen] == '\0') {
69	/* work tree is the root, or the whole path */
70	memmove(path, path + wtlen, len - wtlen + 1);
71	return 0;
72	}
73	/* work tree might match beginning of a symlink to work tree */
74	off = wtlen;
75	}
76	path0 = path;
77	path += off;
78
79	/* check each '/'-terminated level */
80	while (*path) {
81	path++;
82	if (*path == '/') {
83	*path = '\0';
84	strbuf_realpath(&realpath, path0, 1);
85	if (fspathcmp(realpath.buf, work_tree) == 0) {
86	memmove(path0, path + 1, len - (path - path0));
87	strbuf_release(&realpath);
88	return 0;
89	}
90	*path = '/';
91	}
92	}
93
94	/* check whole path */
95	strbuf_realpath(&realpath, path0, 1);
96	if (fspathcmp(realpath.buf, work_tree) == 0) {
97	*path0 = '\0';
98	strbuf_release(&realpath);
99	return 0;
100	}
101
102	strbuf_release(&realpath);
103	return -1;
104	}
105
106	/*
107	* Normalize "path", prepending the "prefix" for relative paths. If
108	* remaining_prefix is not NULL, return the actual prefix still
109	* remains in the path. For example, prefix = sub1/sub2/ and path is
110	*
111	* foo -> sub1/sub2/foo (full prefix)
112	* ../foo -> sub1/foo (remaining prefix is sub1/)
113	* ../../bar -> bar (no remaining prefix)
114	* ../../sub1/sub2/foo -> sub1/sub2/foo (but no remaining prefix)
115	* `pwd`/../bar -> sub1/bar (no remaining prefix)
116	*/
117	char prefix_path_gently(struct repository repo,
118	const char *prefix, int len,
119	int remaining_prefix, const char path)
120	{
121	const char *orig = path;
122	char *sanitized;
123	if (is_absolute_path(orig)) {
124	sanitized = xmallocz(strlen(path));
125	if (remaining_prefix)
126	*remaining_prefix = 0;
127	if (normalize_path_copy_len(sanitized, path, remaining_prefix)) {
128	free(sanitized);
129	return NULL;
130	}
131	if (abspath_part_inside_repo(repo, sanitized)) {
132	free(sanitized);
133	return NULL;
134	}
135	} else {
136	sanitized = xstrfmt("%.*s%s", len, len ? prefix : "", path);
137	if (remaining_prefix)
138	*remaining_prefix = len;
139	if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix)) {
140	free(sanitized);
141	return NULL;
142	}
143	}
144	return sanitized;
145	}
146
147	char prefix_path(struct repository repo, const char prefix, int len, const char path)
148	{
149	char *r = prefix_path_gently(repo, prefix, len, NULL, path);
150	if (!r) {
151	const char *hint_path = repo_get_work_tree(repo);
152	if (!hint_path)
153	hint_path = repo_get_git_dir(repo);
154	die(_("'%s' is outside repository at '%s'"), path,
155	absolute_path(hint_path));
156	}
157	return r;
158	}
159
160	int path_inside_repo(struct repository repo, const char prefix, const char *path)
161	{
162	int len = prefix ? strlen(prefix) : 0;
163	char *r = prefix_path_gently(repo, prefix, len, NULL, path);
164	if (r) {
165	free(r);
166	return 1;
167	}
168	return 0;
169	}
170
171	int check_filename(const char prefix, const char arg)
172	{
173	char *to_free = NULL;
174	struct stat st;
175
176	if (skip_prefix(arg, ":/", &arg)) {
177	if (!arg) / ":/" is root dir, always exists */
178	return 1;
179	prefix = NULL;
180	} else if (skip_prefix(arg, ":!", &arg) \|\|
181	skip_prefix(arg, ":^", &arg)) {
182	if (!arg) / excluding everything is silly, but allowed */
183	return 1;
184	}
185
186	if (prefix)
187	arg = to_free = prefix_filename(prefix, arg);
188
189	if (!lstat(arg, &st)) {
190	free(to_free);
191	return 1; /* file exists */
192	}
193	if (is_missing_file_error(errno)) {
194	free(to_free);
195	return 0; /* file does not exist */
196	}
197	die_errno(_("failed to stat '%s'"), arg);
198	}
199
200	static void NORETURN die_verify_filename(struct repository *r,
201	const char *prefix,
202	const char *arg,
203	int diagnose_misspelt_rev)
204	{
205	if (!diagnose_misspelt_rev)
206	die(_("%s: no such path in the working tree.\n"
207	"Use 'git <command> -- <path>...' to specify paths that do not exist locally."),
208	arg);
209	/*
210	* Saying "'(icase)foo' does not exist in the index" when the
211	* user gave us ":(icase)foo" is just stupid. A magic pathspec
212	* begins with a colon and is followed by a non-alnum; do not
213	* let maybe_die_on_misspelt_object_name() even trigger.
214	*/
215	if (!(arg[0] == ':' && !isalnum(arg[1])))
216	maybe_die_on_misspelt_object_name(r, arg, prefix);
217
218	/* ... or fall back the most general message. */
219	die(_("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
220	"Use '--' to separate paths from revisions, like this:\n"
221	"'git <command> [<revision>...] -- [<file>...]'"), arg);
222
223	}
224
225	/*
226	* Check for arguments that don't resolve as actual files,
227	* but which look sufficiently like pathspecs that we'll consider
228	* them such for the purposes of rev/pathspec DWIM parsing.
229	*/
230	static int looks_like_pathspec(const char *arg)
231	{
232	const char *p;
233	int escaped = 0;
234
235	/*
236	* Wildcard characters imply the user is looking to match pathspecs
237	* that aren't in the filesystem. Note that this doesn't include
238	* backslash even though it's a glob special; by itself it doesn't
239	* cause any increase in the match. Likewise ignore backslash-escaped
240	* wildcard characters.
241	*/
242	for (p = arg; *p; p++) {
243	if (escaped) {
244	escaped = 0;
245	} else if (is_glob_special(*p)) {
246	if (*p == '\\')
247	escaped = 1;
248	else
249	return 1;
250	}
251	}
252
253	/* long-form pathspec magic */
254	if (starts_with(arg, ":("))
255	return 1;
256
257	return 0;
258	}
259
260	/*
261	* Verify a filename that we got as an argument for a pathspec
262	* entry. Note that a filename that begins with "-" never verifies
263	* as true, because even if such a filename were to exist, we want
264	* it to be preceded by the "--" marker (or we want the user to
265	* use a format like "./-filename")
266	*
267	* The "diagnose_misspelt_rev" is used to provide a user-friendly
268	* diagnosis when dying upon finding that "name" is not a pathname.
269	* If set to 1, the diagnosis will try to diagnose "name" as an
270	* invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
271	* will only complain about an inexisting file.
272	*
273	* This function is typically called to check that a "file or rev"
274	* argument is unambiguous. In this case, the caller will want
275	* diagnose_misspelt_rev == 1 when verifying the first non-rev
276	* argument (which could have been a revision), and
277	* diagnose_misspelt_rev == 0 for the next ones (because we already
278	* saw a filename, there's not ambiguity anymore).
279	*/
280	void verify_filename(struct repository *repo,
281	const char *prefix,
282	const char *arg,
283	int diagnose_misspelt_rev)
284	{
285	if (*arg == '-')
286	die(_("option '%s' must come before non-option arguments"), arg);
287	if (looks_like_pathspec(arg) \|\| check_filename(prefix, arg))
288	return;
289	die_verify_filename(repo, prefix, arg, diagnose_misspelt_rev);
290	}
291
292	/*
293	* Opposite of the above: the command line did not have -- marker
294	* and we parsed the arg as a refname. It should not be interpretable
295	* as a filename.
296	*/
297	void verify_non_filename(struct repository repo, const char prefix, const char *arg)
298	{
299	if (!is_inside_work_tree(repo) \|\| is_inside_git_dir(repo))
300	return;
301	if (*arg == '-')
302	return; /* flag */
303	if (!check_filename(prefix, arg))
304	return;
305	die(_("ambiguous argument '%s': both revision and filename\n"
306	"Use '--' to separate paths from revisions, like this:\n"
307	"'git <command> [<revision>...] -- [<file>...]'"), arg);
308	}
309
310	int get_common_dir(struct strbuf sb, const char gitdir)
311	{
312	const char *git_env_common_dir = getenv(GIT_COMMON_DIR_ENVIRONMENT);
313	if (git_env_common_dir) {
314	strbuf_addstr(sb, git_env_common_dir);
315	return 1;
316	} else {
317	return get_common_dir_noenv(sb, gitdir);
318	}
319	}
320
321	int get_common_dir_noenv(struct strbuf sb, const char gitdir)
322	{
323	struct strbuf data = STRBUF_INIT;
324	struct strbuf path = STRBUF_INIT;
325	int ret = 0;
326
327	strbuf_addf(&path, "%s/commondir", gitdir);
328	if (file_exists(path.buf)) {
329	if (strbuf_read_file(&data, path.buf, 0) <= 0)
330	die_errno(_("failed to read %s"), path.buf);
331	while (data.len && (data.buf[data.len - 1] == '\n' \|\|
332	data.buf[data.len - 1] == '\r'))
333	data.len--;
334	data.buf[data.len] = '\0';
335	strbuf_reset(&path);
336	if (!is_absolute_path(data.buf))
337	strbuf_addf(&path, "%s/", gitdir);
338	strbuf_addbuf(&path, &data);
339	strbuf_add_real_path(sb, path.buf);
340	ret = 1;
341	} else {
342	strbuf_addstr(sb, gitdir);
343	}
344
345	strbuf_release(&data);
346	strbuf_release(&path);
347	return ret;
348	}
349
350	static int validate_headref(const char *path)
351	{
352	struct stat st;
353	char buffer[256];
354	const char *refname;
355	struct object_id oid;
356	int fd;
357	ssize_t len;
358
359	if (lstat(path, &st) < 0)
360	return -1;
361
362	/* Make sure it is a "refs/.." symlink */
363	if (S_ISLNK(st.st_mode)) {
364	len = readlink(path, buffer, sizeof(buffer)-1);
365	if (len >= 5 && !memcmp("refs/", buffer, 5))
366	return 0;
367	return -1;
368	}
369
370	/*
371	* Anything else, just open it and try to see if it is a symbolic ref.
372	*/
373	fd = open(path, O_RDONLY);
374	if (fd < 0)
375	return -1;
376	len = read_in_full(fd, buffer, sizeof(buffer)-1);
377	close(fd);
378
379	if (len < 0)
380	return -1;
381	buffer[len] = '\0';
382
383	/*
384	* Is it a symbolic ref?
385	*/
386	if (skip_prefix(buffer, "ref:", &refname)) {
387	while (isspace(*refname))
388	refname++;
389	if (starts_with(refname, "refs/"))
390	return 0;
391	}
392
393	/*
394	* Is this a detached HEAD?
395	*/
396	if (get_oid_hex_any(buffer, &oid) != GIT_HASH_UNKNOWN)
397	return 0;
398
399	return -1;
400	}
401
402	/*
403	* Test if it looks like we're at a git directory.
404	* We want to see:
405	*
406	* - either an objects/ directory _or_ the proper
407	* GIT_OBJECT_DIRECTORY environment variable
408	* - a refs/ directory
409	* - either a HEAD symlink or a HEAD file that is formatted as
410	* a proper "ref:", or a regular file HEAD that has a properly
411	* formatted sha1 object name.
412	*/
413	int is_git_directory(const char *suspect)
414	{
415	struct strbuf path = STRBUF_INIT;
416	int ret = 0;
417	size_t len;
418
419	/* Check worktree-related signatures */
420	strbuf_addstr(&path, suspect);
421	strbuf_complete(&path, '/');
422	strbuf_addstr(&path, "HEAD");
423	if (validate_headref(path.buf))
424	goto done;
425
426	strbuf_reset(&path);
427	get_common_dir(&path, suspect);
428	len = path.len;
429
430	/* Check non-worktree-related signatures */
431	if (getenv(DB_ENVIRONMENT)) {
432	if (access(getenv(DB_ENVIRONMENT), X_OK))
433	goto done;
434	}
435	else {
436	strbuf_setlen(&path, len);
437	strbuf_addstr(&path, "/objects");
438	if (access(path.buf, X_OK))
439	goto done;
440	}
441
442	strbuf_setlen(&path, len);
443	strbuf_addstr(&path, "/refs");
444	if (access(path.buf, X_OK))
445	goto done;
446
447	ret = 1;
448	done:
449	strbuf_release(&path);
450	return ret;
451	}
452
453	int is_nonbare_repository_dir(struct strbuf *path)
454	{
455	int ret = 0;
456	int gitfile_error;
457	size_t orig_path_len = path->len;
458	assert(orig_path_len != 0);
459	strbuf_complete(path, '/');
460	strbuf_addstr(path, ".git");
461	if (read_gitfile_gently(path->buf, &gitfile_error) \|\| is_git_directory(path->buf))
462	ret = 1;
463	if (gitfile_error == READ_GITFILE_ERR_OPEN_FAILED \|\|
464	gitfile_error == READ_GITFILE_ERR_READ_FAILED)
465	ret = 1;
466	strbuf_setlen(path, orig_path_len);
467	return ret;
468	}
469
470	int is_inside_git_dir(struct repository *repo)
471	{
472	struct strbuf buf = STRBUF_INIT;
473	int ret = is_inside_dir(strbuf_realpath(&buf, repo_get_git_dir(repo), 1));
474	strbuf_release(&buf);
475	return ret;
476	}
477
478	int is_inside_work_tree(struct repository *repo)
479	{
480	struct strbuf buf = STRBUF_INIT;
481	const char *worktree;
482	int ret;
483
484	worktree = repo_get_work_tree(repo);
485	if (!worktree)
486	return 0;
487
488	ret = is_inside_dir(strbuf_realpath(&buf, worktree, 1));
489
490	strbuf_release(&buf);
491	return ret;
492	}
493
494	void setup_work_tree(struct repository *repo)
495	{
496	const char *work_tree;
497
498	if (repo->worktree_config_is_bogus)
499	die(_("unable to set up work tree using invalid config"));
500
501	work_tree = repo_get_work_tree(repo);
502	if (!work_tree \|\| chdir_notify(work_tree))
503	die(_("this operation must be run in a work tree"));
504
505	/*
506	* Make sure subsequent git processes find correct worktree
507	* if $GIT_WORK_TREE is set relative
508	*/
509	if (getenv(GIT_WORK_TREE_ENVIRONMENT))
510	setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
511	}
512
513	static void setup_original_cwd(struct repository *repo)
514	{
515	struct strbuf tmp = STRBUF_INIT;
516	const char *worktree = NULL;
517	int offset = -1;
518
519	if (!tmp_original_cwd)
520	return;
521
522	/*
523	* startup_info->original_cwd points to the current working
524	* directory we inherited from our parent process, which is a
525	* directory we want to avoid removing.
526	*
527	* For convenience, we would like to have the path relative to the
528	* worktree instead of an absolute path.
529	*
530	* Yes, startup_info->original_cwd is usually the same as 'prefix',
531	* but differs in two ways:
532	* - prefix has a trailing '/'
533	* - if the user passes '-C' to git, that modifies the prefix but
534	* not startup_info->original_cwd.
535	*/
536
537	/* Normalize the directory */
538	if (!strbuf_realpath(&tmp, tmp_original_cwd, 0)) {
539	trace2_data_string("setup", repo,
540	"realpath-path", tmp_original_cwd);
541	trace2_data_string("setup", repo,
542	"realpath-failure", strerror(errno));
543	free((char*)tmp_original_cwd);
544	tmp_original_cwd = NULL;
545	return;
546	}
547
548	free((char*)tmp_original_cwd);
549	tmp_original_cwd = NULL;
550	startup_info->original_cwd = strbuf_detach(&tmp, NULL);
551
552	/*
553	* Get our worktree; we only protect the current working directory
554	* if it's in the worktree.
555	*/
556	worktree = repo_get_work_tree(repo);
557	if (!worktree)
558	goto no_prevention_needed;
559
560	offset = dir_inside_of(startup_info->original_cwd, worktree);
561	if (offset >= 0) {
562	/*
563	* If startup_info->original_cwd == worktree, that is already
564	* protected and we don't need original_cwd as a secondary
565	* protection measure.
566	*/
567	if (!*(startup_info->original_cwd + offset))
568	goto no_prevention_needed;
569
570	/*
571	* original_cwd was inside worktree; precompose it just as
572	* we do prefix so that built up paths will match
573	*/
574	startup_info->original_cwd = \
575	precompose_string_if_needed(startup_info->original_cwd
576	+ offset);
577	return;
578	}
579
580	no_prevention_needed:
581	free((char*)startup_info->original_cwd);
582	startup_info->original_cwd = NULL;
583	}
584
585	static int read_worktree_config(const char var, const char value,
586	const struct config_context *ctx UNUSED,
587	void *vdata)
588	{
589	struct repository_format *data = vdata;
590
591	if (strcmp(var, "core.bare") == 0) {
592	data->is_bare = git_config_bool(var, value);
593	} else if (strcmp(var, "core.worktree") == 0) {
594	if (!value)
595	return config_error_nonbool(var);
596	free(data->work_tree);
597	data->work_tree = xstrdup(value);
598	}
599	return 0;
600	}
601
602	enum extension_result {
603	EXTENSION_ERROR = -1, /* compatible with error(), etc */
604	EXTENSION_UNKNOWN = 0,
605	EXTENSION_OK = 1
606	};
607
608	/*
609	* Do not add new extensions to this function. It handles extensions which are
610	* respected even in v0-format repositories for historical compatibility.
611	*/
612	static enum extension_result handle_extension_v0(const char *var,
613	const char *value,
614	const char *ext,
615	struct repository_format *data)
616	{
617	if (!strcmp(ext, "noop")) {
618	return EXTENSION_OK;
619	} else if (!strcmp(ext, "preciousobjects")) {
620	data->precious_objects = git_config_bool(var, value);
621	return EXTENSION_OK;
622	} else if (!strcmp(ext, "partialclone")) {
623	if (!value)
624	return config_error_nonbool(var);
625	data->partial_clone = xstrdup(value);
626	return EXTENSION_OK;
627	} else if (!strcmp(ext, "worktreeconfig")) {
628	data->worktree_config = git_config_bool(var, value);
629	return EXTENSION_OK;
630	}
631
632	return EXTENSION_UNKNOWN;
633	}
634
635	static void parse_reference_uri(const char value, char *format,
636	char **payload)
637	{
638	const char *schema_end;
639
640	schema_end = strstr(value, "://");
641	if (!schema_end) {
642	*format = xstrdup(value);
643	*payload = NULL;
644	} else {
645	*format = xstrndup(value, schema_end - value);
646	*payload = xstrdup_or_null(schema_end + 3);
647	}
648	}
649
650	/*
651	* Record any new extensions in this function.
652	*/
653	static enum extension_result handle_extension(const char *var,
654	const char *value,
655	const char *ext,
656	struct repository_format *data)
657	{
658	if (!strcmp(ext, "noop-v1")) {
659	return EXTENSION_OK;
660	} else if (!strcmp(ext, "objectformat")) {
661	int format;
662
663	if (!value)
664	return config_error_nonbool(var);
665	format = hash_algo_by_name(value);
666	if (format == GIT_HASH_UNKNOWN)
667	return error(_("invalid value for '%s': '%s'"),
668	"extensions.objectformat", value);
669	data->hash_algo = format;
670	return EXTENSION_OK;
671	} else if (!strcmp(ext, "compatobjectformat")) {
672	struct string_list_item *item;
673	int format;
674
675	if (!value)
676	return config_error_nonbool(var);
677	format = hash_algo_by_name(value);
678	if (format == GIT_HASH_UNKNOWN)
679	return error(_("invalid value for '%s': '%s'"),
680	"extensions.compatobjectformat", value);
681	/* For now only support compatObjectFormat being specified once. */
682	for_each_string_list_item(item, &data->v1_only_extensions) {
683	if (!strcmp(item->string, "compatobjectformat"))
684	return error(_("'%s' already specified as '%s'"),
685	"extensions.compatobjectformat",
686	hash_algos[data->compat_hash_algo].name);
687	}
688	data->compat_hash_algo = format;
689	return EXTENSION_OK;
690	} else if (!strcmp(ext, "refstorage")) {
691	unsigned int format;
692	char *format_str;
693
694	if (!value)
695	return config_error_nonbool(var);
696
697	parse_reference_uri(value, &format_str,
698	&data->ref_storage_payload);
699
700	format = ref_storage_format_by_name(format_str);
701	free(format_str);
702
703	if (format == REF_STORAGE_FORMAT_UNKNOWN)
704	return error(_("invalid value for '%s': '%s'"),
705	"extensions.refstorage", value);
706	data->ref_storage_format = format;
707	return EXTENSION_OK;
708	} else if (!strcmp(ext, "relativeworktrees")) {
709	data->relative_worktrees = git_config_bool(var, value);
710	return EXTENSION_OK;
711	} else if (!strcmp(ext, "submodulepathconfig")) {
712	data->submodule_path_cfg = git_config_bool(var, value);
713	return EXTENSION_OK;
714	}
715	return EXTENSION_UNKNOWN;
716	}
717
718	static int check_repo_format(const char var, const char value,
719	const struct config_context ctx, void vdata)
720	{
721	struct repository_format *data = vdata;
722	const char *ext;
723
724	if (strcmp(var, "core.repositoryformatversion") == 0)
725	data->version = git_config_int(var, value, ctx->kvi);
726	else if (skip_prefix(var, "extensions.", &ext)) {
727	switch (handle_extension_v0(var, value, ext, data)) {
728	case EXTENSION_ERROR:
729	return -1;
730	case EXTENSION_OK:
731	return 0;
732	case EXTENSION_UNKNOWN:
733	break;
734	}
735
736	switch (handle_extension(var, value, ext, data)) {
737	case EXTENSION_ERROR:
738	return -1;
739	case EXTENSION_OK:
740	string_list_append(&data->v1_only_extensions, ext);
741	return 0;
742	case EXTENSION_UNKNOWN:
743	string_list_append(&data->unknown_extensions, ext);
744	return 0;
745	}
746	}
747
748	return read_worktree_config(var, value, ctx, vdata);
749	}
750
751	static int read_and_verify_repository_format(struct repository_format *format,
752	const char *gitdir,
753	int *nongit_ok)
754	{
755	struct strbuf sb = STRBUF_INIT;
756	struct strbuf err = STRBUF_INIT;
757	int has_common;
758
759	has_common = get_common_dir(&sb, gitdir);
760	strbuf_addstr(&sb, "/config");
761	read_repository_format(format, sb.buf);
762	strbuf_release(&sb);
763
764	/*
765	* For historical use of check_and_apply_repository_format() in git-init,
766	* we treat a missing config as a silent "ok", even when nongit_ok
767	* is unset.
768	*/
769	if (format->version < 0)
770	return 0;
771
772	if (verify_repository_format(format, &err) < 0) {
773	if (nongit_ok) {
774	warning("%s", err.buf);
775	strbuf_release(&err);
776	*nongit_ok = -1;
777	return -1;
778	}
779	die("%s", err.buf);
780	}
781
782	string_list_clear(&format->unknown_extensions, 0);
783	string_list_clear(&format->v1_only_extensions, 0);
784
785	if (format->worktree_config) {
786	/*
787	* pick up core.bare and core.worktree from per-worktree
788	* config if present
789	*/
790	strbuf_addf(&sb, "%s/config.worktree", gitdir);
791	git_config_from_file(read_worktree_config, sb.buf, format);
792	strbuf_release(&sb);
793	has_common = 0;
794	}
795
796	if (startup_info->force_bare_repository) {
797	format->is_bare = 1;
798	FREE_AND_NULL(format->work_tree);
799	} else if (has_common) {
800	/*
801	* When sharing a common dir with another repository (e.g. a
802	* linked worktree), do not let this repository's config
803	* dictate bareness; it is inherited from the main worktree.
804	*/
805	format->is_bare = -1;
806
807	/*
808	* Furthermore, "core.worktree" is supposed to be ignored when
809	* we have a commondir configured, unless it comes from the
810	* per-worktree configuration.
811	*/
812	FREE_AND_NULL(format->work_tree);
813	}
814
815	return 0;
816	}
817
818	int upgrade_repository_format(struct repository *repo, int target_version)
819	{
820	struct strbuf sb = STRBUF_INIT;
821	struct strbuf err = STRBUF_INIT;
822	struct strbuf repo_version = STRBUF_INIT;
823	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
824	int ret;
825
826	repo_common_path_append(repo, &sb, "config");
827	read_repository_format(&repo_fmt, sb.buf);
828	strbuf_release(&sb);
829
830	if (repo_fmt.version >= target_version) {
831	ret = 0;
832	goto out;
833	}
834
835	if (verify_repository_format(&repo_fmt, &err) < 0) {
836	ret = error("cannot upgrade repository format from %d to %d: %s",
837	repo_fmt.version, target_version, err.buf);
838	goto out;
839	}
840	if (!repo_fmt.version && repo_fmt.unknown_extensions.nr) {
841	ret = error("cannot upgrade repository format: "
842	"unknown extension %s",
843	repo_fmt.unknown_extensions.items[0].string);
844	goto out;
845	}
846
847	strbuf_addf(&repo_version, "%d", target_version);
848	repo_config_set(repo, "core.repositoryformatversion", repo_version.buf);
849
850	ret = 1;
851
852	out:
853	clear_repository_format(&repo_fmt);
854	strbuf_release(&repo_version);
855	strbuf_release(&err);
856	return ret;
857	}
858
859	static void init_repository_format(struct repository_format *format)
860	{
861	const struct repository_format fresh = REPOSITORY_FORMAT_INIT;
862
863	memcpy(format, &fresh, sizeof(fresh));
864	}
865
866	int read_repository_format(struct repository_format format, const char path)
867	{
868	clear_repository_format(format);
869	format->hash_algo = GIT_HASH_SHA1_LEGACY;
870	git_config_from_file(check_repo_format, path, format);
871	if (format->version == -1) {
872	clear_repository_format(format);
873	format->hash_algo = GIT_HASH_SHA1_LEGACY;
874	}
875	return format->version;
876	}
877
878	void clear_repository_format(struct repository_format *format)
879	{
880	string_list_clear(&format->unknown_extensions, 0);
881	string_list_clear(&format->v1_only_extensions, 0);
882	free(format->work_tree);
883	free(format->partial_clone);
884	free(format->ref_storage_payload);
885	init_repository_format(format);
886	}
887
888	int verify_repository_format(const struct repository_format *format,
889	struct strbuf *err)
890	{
891	if (GIT_REPO_VERSION_READ < format->version) {
892	strbuf_addf(err, _("Expected git repo version <= %d, found %d"),
893	GIT_REPO_VERSION_READ, format->version);
894	return -1;
895	}
896
897	if (format->version >= 1 && format->unknown_extensions.nr) {
898	int i;
899
900	strbuf_addstr(err, Q_("unknown repository extension found:",
901	"unknown repository extensions found:",
902	format->unknown_extensions.nr));
903
904	for (i = 0; i < format->unknown_extensions.nr; i++)
905	strbuf_addf(err, "\n\t%s",
906	format->unknown_extensions.items[i].string);
907	return -1;
908	}
909
910	if (format->version == 0 && format->v1_only_extensions.nr) {
911	int i;
912
913	strbuf_addstr(err,
914	Q_("repo version is 0, but v1-only extension found:",
915	"repo version is 0, but v1-only extensions found:",
916	format->v1_only_extensions.nr));
917
918	for (i = 0; i < format->v1_only_extensions.nr; i++)
919	strbuf_addf(err, "\n\t%s",
920	format->v1_only_extensions.items[i].string);
921	return -1;
922	}
923
924	return 0;
925	}
926
927	void read_gitfile_error_die(int error_code, const char *path)
928	{
929	switch (error_code) {
930	case READ_GITFILE_ERR_NOT_A_FILE:
931	case READ_GITFILE_ERR_STAT_FAILED:
932	case READ_GITFILE_ERR_MISSING:
933	case READ_GITFILE_ERR_IS_A_DIR:
934	/* non-fatal; follow return path */
935	break;
936	case READ_GITFILE_ERR_OPEN_FAILED:
937	die_errno(_("error opening '%s'"), path);
938	case READ_GITFILE_ERR_TOO_LARGE:
939	die(_("too large to be a .git file: '%s'"), path);
940	case READ_GITFILE_ERR_READ_FAILED:
941	die(_("error reading %s"), path);
942	case READ_GITFILE_ERR_INVALID_FORMAT:
943	die(_("invalid gitfile format: %s"), path);
944	case READ_GITFILE_ERR_NO_PATH:
945	die(_("no path in gitfile: %s"), path);
946	case READ_GITFILE_ERR_NOT_A_REPO:
947	die(_("gitfile does not point to a valid repository: %s"),
948	path);
949	default:
950	BUG("unknown error code");
951	}
952	}
953
954	/*
955	* Try to read the location of the git directory from the .git file,
956	* return path to git directory if found. The return value comes from
957	* a shared buffer.
958	*
959	* On failure, if return_error_code is not NULL, return_error_code
960	* will be set to an error code and NULL will be returned. If
961	* return_error_code is NULL the function will die instead (for most
962	* cases).
963	*/
964	const char read_gitfile_gently(const char path, int *return_error_code)
965	{
966	const int max_file_size = 1 << 20; /* 1MB */
967	int error_code = 0;
968	char *buf = NULL;
969	char *dir = NULL;
970	const char *slash;
971	struct stat st;
972	int fd;
973	ssize_t len;
974	static struct strbuf realpath = STRBUF_INIT;
975
976	if (stat(path, &st)) {
977	if (errno == ENOENT \|\| errno == ENOTDIR)
978	error_code = READ_GITFILE_ERR_MISSING;
979	else
980	error_code = READ_GITFILE_ERR_STAT_FAILED;
981	goto cleanup_return;
982	}
983	if (S_ISDIR(st.st_mode)) {
984	error_code = READ_GITFILE_ERR_IS_A_DIR;
985	goto cleanup_return;
986	}
987	if (!S_ISREG(st.st_mode)) {
988	error_code = READ_GITFILE_ERR_NOT_A_FILE;
989	goto cleanup_return;
990	}
991	if (st.st_size > max_file_size) {
992	error_code = READ_GITFILE_ERR_TOO_LARGE;
993	goto cleanup_return;
994	}
995	fd = open(path, O_RDONLY);
996	if (fd < 0) {
997	error_code = READ_GITFILE_ERR_OPEN_FAILED;
998	goto cleanup_return;
999	}
1000	buf = xmallocz(st.st_size);
1001	len = read_in_full(fd, buf, st.st_size);
1002	close(fd);
1003	if (len != st.st_size) {
1004	error_code = READ_GITFILE_ERR_READ_FAILED;
1005	goto cleanup_return;
1006	}
1007	if (!starts_with(buf, "gitdir: ")) {
1008	error_code = READ_GITFILE_ERR_INVALID_FORMAT;
1009	goto cleanup_return;
1010	}
1011	while (buf[len - 1] == '\n' \|\| buf[len - 1] == '\r')
1012	len--;
1013	if (len < 9) {
1014	error_code = READ_GITFILE_ERR_NO_PATH;
1015	goto cleanup_return;
1016	}
1017	buf[len] = '\0';
1018	dir = buf + 8;
1019
1020	if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
1021	size_t pathlen = slash+1 - path;
1022	dir = xstrfmt("%.s%.s", (int)pathlen, path,
1023	(int)(len - 8), buf + 8);
1024	free(buf);
1025	buf = dir;
1026	}
1027	if (!is_git_directory(dir)) {
1028	error_code = READ_GITFILE_ERR_NOT_A_REPO;
1029	goto cleanup_return;
1030	}
1031
1032	strbuf_realpath(&realpath, dir, 1);
1033	path = realpath.buf;
1034
1035	cleanup_return:
1036	if (return_error_code)
1037	*return_error_code = error_code;
1038	else if (error_code)
1039	read_gitfile_error_die(error_code, path);
1040
1041	free(buf);
1042	return error_code ? NULL : path;
1043	}
1044
1045	static void apply_gitdir_and_environment(struct repository repo, const char path)
1046	{
1047	struct strvec to_free = STRVEC_INIT;
1048	struct set_gitdir_args args = {
1049	.commondir = getenv_safe(&to_free, GIT_COMMON_DIR_ENVIRONMENT),
1050	.graft_file = getenv_safe(&to_free, GRAFT_ENVIRONMENT),
1051	.index_file = getenv_safe(&to_free, INDEX_ENVIRONMENT),
1052	.disable_ref_updates = !!getenv(GIT_QUARANTINE_ENVIRONMENT),
1053	};
1054
1055	repo_set_gitdir(repo, path, &args);
1056
1057	strvec_clear(&to_free);
1058	}
1059
1060	static void update_relative_gitdir(const char *name UNUSED,
1061	const char *old_cwd,
1062	const char *new_cwd,
1063	void *data)
1064	{
1065	struct repository *repo = data;
1066	char *path = reparent_relative_path(old_cwd, new_cwd,
1067	repo_get_git_dir(repo));
1068	trace_printf_key(&trace_setup_key,
1069	"setup: move $GIT_DIR to '%s'",
1070	path);
1071	apply_gitdir_and_environment(repo, path);
1072	xsetenv(GIT_DIR_ENVIRONMENT, path, 1);
1073	free(path);
1074	}
1075
1076	static void apply_and_export_relative_gitdir(struct repository repo, const char path, int make_realpath)
1077	{
1078	struct strbuf realpath = STRBUF_INIT;
1079
1080	if (make_realpath) {
1081	strbuf_realpath(&realpath, path, 1);
1082	path = realpath.buf;
1083	}
1084
1085	apply_gitdir_and_environment(repo, path);
1086	xsetenv(GIT_DIR_ENVIRONMENT, path, 1);
1087
1088	if (!is_absolute_path(path))
1089	chdir_notify_register(NULL, update_relative_gitdir, repo);
1090
1091	strbuf_release(&realpath);
1092	}
1093
1094	struct repo_discovery {
1095	struct repository_format format;
1096	char *gitdir;
1097	char *worktree;
1098	char *prefix;
1099	};
1100
1101	#define REPO_DISCOVERY_INIT { \
1102	.format = REPOSITORY_FORMAT_INIT, \
1103	}
1104
1105	static void repo_discovery_release(struct repo_discovery *r)
1106	{
1107	clear_repository_format(&r->format);
1108	free(r->gitdir);
1109	free(r->worktree);
1110	free(r->prefix);
1111	}
1112
1113	static void repo_discovery_set_gitdir(struct repo_discovery *r,
1114	const char *gitdir,
1115	int make_realpath)
1116	{
1117	free(r->gitdir);
1118	if (make_realpath) {
1119	struct strbuf realpath = STRBUF_INIT;
1120	strbuf_realpath(&realpath, gitdir, 1);
1121	r->gitdir = strbuf_detach(&realpath, NULL);
1122	} else {
1123	r->gitdir = xstrdup(gitdir);
1124	}
1125	}
1126
1127	static void repo_discovery_set_worktree(struct repo_discovery *r,
1128	const char *worktree)
1129	{
1130	free(r->worktree);
1131	r->worktree = real_pathdup(worktree, 1);
1132	}
1133
1134	static void repo_discover_explicit_gitdir(struct repo_discovery *discovery,
1135	const char *gitdirenv,
1136	struct strbuf *cwd,
1137	int *nongit_ok)
1138	{
1139	const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
1140	char *gitfile;
1141	int offset;
1142
1143	if (PATH_MAX - 40 < strlen(gitdirenv))
1144	die(_("'$%s' too big"), GIT_DIR_ENVIRONMENT);
1145
1146	gitfile = (char*)read_gitfile(gitdirenv);
1147	if (gitfile) {
1148	gitfile = xstrdup(gitfile);
1149	gitdirenv = gitfile;
1150	}
1151
1152	if (!is_git_directory(gitdirenv)) {
1153	if (nongit_ok) {
1154	*nongit_ok = 1;
1155	goto out;
1156	}
1157	die(_("not a git repository: '%s'"), gitdirenv);
1158	}
1159
1160	if (read_and_verify_repository_format(&discovery->format, gitdirenv, nongit_ok))
1161	goto out;
1162
1163	/* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
1164	if (work_tree_env) {
1165	/*
1166	* The environment variable overrides "core.worktree". This
1167	* also has the consequence that we don't want to flag cases as
1168	* bogus where we have both "core.worktree" and "core.bare", so
1169	* we have to explicitly unset the configuration.
1170	*/
1171	FREE_AND_NULL(discovery->format.work_tree);
1172	repo_discovery_set_worktree(discovery, work_tree_env);
1173	} else if (discovery->format.is_bare > 0) {
1174	/* #18, #26 */
1175	repo_discovery_set_gitdir(discovery, gitdirenv, 0);
1176	goto out;
1177	} else if (discovery->format.work_tree) { /* #6, #14 */
1178	if (is_absolute_path(discovery->format.work_tree)) {
1179	repo_discovery_set_worktree(discovery, discovery->format.work_tree);
1180	} else {
1181	char *core_worktree;
1182	if (chdir(gitdirenv))
1183	die_errno(_("cannot chdir to '%s'"), gitdirenv);
1184	if (chdir(discovery->format.work_tree))
1185	die_errno(_("cannot chdir to '%s'"), discovery->format.work_tree);
1186	core_worktree = xgetcwd();
1187	if (chdir(cwd->buf))
1188	die_errno(_("cannot come back to cwd"));
1189	repo_discovery_set_worktree(discovery, core_worktree);
1190	free(core_worktree);
1191	}
1192	} else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {
1193	/* #16d */
1194	repo_discovery_set_gitdir(discovery, gitdirenv, 0);
1195	goto out;
1196	} else { /* #2, #10 */
1197	repo_discovery_set_worktree(discovery, ".");
1198	}
1199
1200	/* both the worktree and cwd are already normalized */
1201	if (!strcmp(cwd->buf, discovery->worktree)) { /* cwd == worktree */
1202	repo_discovery_set_gitdir(discovery, gitdirenv, 0);
1203	goto out;
1204	}
1205
1206	offset = dir_inside_of(cwd->buf, discovery->worktree);
1207	if (offset >= 0) { /* cwd inside discovery->worktree? */
1208	repo_discovery_set_gitdir(discovery, gitdirenv, 1);
1209	if (chdir(discovery->worktree))
1210	die_errno(_("cannot chdir to '%s'"), discovery->worktree);
1211	discovery->prefix = xstrfmt("%s/", cwd->buf + offset);
1212	goto out;
1213	}
1214
1215	/* cwd outside worktree */
1216	repo_discovery_set_gitdir(discovery, gitdirenv, 0);
1217
1218	out:
1219	free(gitfile);
1220	}
1221
1222	static void repo_discover_implicit_gitdir(struct repo_discovery *discovery,
1223	const char *gitdir,
1224	struct strbuf *cwd, int offset,
1225	int *nongit_ok)
1226	{
1227	if (read_and_verify_repository_format(&discovery->format, gitdir, nongit_ok))
1228	return;
1229
1230	/* --work-tree is set without --git-dir; use discovered one */
1231	if (getenv(GIT_WORK_TREE_ENVIRONMENT) \|\| discovery->format.work_tree) {
1232	char *to_free = NULL;
1233
1234	if (offset != cwd->len && !is_absolute_path(gitdir))
1235	gitdir = to_free = real_pathdup(gitdir, 1);
1236	if (chdir(cwd->buf))
1237	die_errno(_("cannot come back to cwd"));
1238	repo_discover_explicit_gitdir(discovery, gitdir, cwd,
1239	nongit_ok);
1240	free(to_free);
1241	return;
1242	}
1243
1244	/* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
1245	if (discovery->format.is_bare > 0) {
1246	repo_discovery_set_gitdir(discovery, gitdir, (offset != cwd->len));
1247	if (chdir(cwd->buf))
1248	die_errno(_("cannot come back to cwd"));
1249	return;
1250	}
1251
1252	/* #0, #1, #5, #8, #9, #12, #13 */
1253	repo_discovery_set_worktree(discovery, ".");
1254	if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
1255	repo_discovery_set_gitdir(discovery, gitdir, 0);
1256	if (offset >= cwd->len)
1257	return;
1258
1259	/* Make "offset" point past the '/' (already the case for root dirs) */
1260	if (offset != offset_1st_component(cwd->buf))
1261	offset++;
1262	discovery->prefix = xstrfmt("%s/", cwd->buf + offset);
1263	}
1264
1265	/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
1266	static void repo_discover_bare_gitdir(struct repo_discovery *discovery,
1267	struct strbuf *cwd, int offset,
1268	int *nongit_ok)
1269	{
1270	int root_len;
1271
1272	if (read_and_verify_repository_format(&discovery->format, ".", nongit_ok))
1273	return;
1274
1275	setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
1276
1277	/* --work-tree is set without --git-dir; use discovered one */
1278	if (getenv(GIT_WORK_TREE_ENVIRONMENT) \|\| discovery->format.work_tree) {
1279	char *gitdir = offset == cwd->len ? xstrdup(".") : xmemdupz(cwd->buf, offset);
1280	if (chdir(cwd->buf))
1281	die_errno(_("cannot come back to cwd"));
1282	repo_discover_explicit_gitdir(discovery, gitdir, cwd, nongit_ok);
1283	free(gitdir);
1284	return;
1285	}
1286
1287	if (offset != cwd->len) {
1288	if (chdir(cwd->buf))
1289	die_errno(_("cannot come back to cwd"));
1290	root_len = offset_1st_component(cwd->buf);
1291	strbuf_setlen(cwd, offset > root_len ? offset : root_len);
1292	repo_discovery_set_gitdir(discovery, cwd->buf, 0);
1293	} else {
1294	repo_discovery_set_gitdir(discovery, ".", 0);
1295	}
1296	}
1297
1298	static dev_t get_device_or_die(const char path, const char prefix, int prefix_len)
1299	{
1300	struct stat buf;
1301	if (stat(path, &buf)) {
1302	die_errno(_("failed to stat '%*s%s%s'"),
1303	prefix_len,
1304	prefix ? prefix : "",
1305	prefix ? "/" : "", path);
1306	}
1307	return buf.st_dev;
1308	}
1309
1310	/*
1311	* A "string_list_each_func_t" function that canonicalizes an entry
1312	* from GIT_CEILING_DIRECTORIES using real_pathdup(), or
1313	* discards it if unusable. The presence of an empty entry in
1314	* GIT_CEILING_DIRECTORIES turns off canonicalization for all
1315	* subsequent entries.
1316	*/
1317	static int canonicalize_ceiling_entry(struct string_list_item *item,
1318	void *cb_data)
1319	{
1320	int *empty_entry_found = cb_data;
1321	char *ceil = item->string;
1322
1323	if (!*ceil) {
1324	*empty_entry_found = 1;
1325	return 0;
1326	} else if (!is_absolute_path(ceil)) {
1327	return 0;
1328	} else if (*empty_entry_found) {
1329	/* Keep entry but do not canonicalize it */
1330	return 1;
1331	} else {
1332	char *real_path = real_pathdup(ceil, 0);
1333	if (!real_path) {
1334	return 0;
1335	}
1336	free(item->string);
1337	item->string = real_path;
1338	return 1;
1339	}
1340	}
1341
1342	struct safe_directory_data {
1343	char *path;
1344	int is_safe;
1345	};
1346
1347	static int safe_directory_cb(const char key, const char value,
1348	const struct config_context ctx UNUSED, void d)
1349	{
1350	struct safe_directory_data *data = d;
1351
1352	if (strcmp(key, "safe.directory"))
1353	return 0;
1354
1355	if (!value \|\| !*value) {
1356	data->is_safe = 0;
1357	} else if (!strcmp(value, "*")) {
1358	data->is_safe = 1;
1359	} else {
1360	char *allowed = NULL;
1361
1362	if (!git_config_pathname(&allowed, key, value) && allowed) {
1363	char *normalized = NULL;
1364
1365	/*
1366	* Setting safe.directory to a non-absolute path
1367	* makes little sense---it won't be relative to
1368	* the configuration file the item is defined in.
1369	* Except for ".", which means "if we are at the top
1370	* level of a repository, then it is OK", which is
1371	* slightly tighter than "*" that allows discovery.
1372	*/
1373	if (!is_absolute_path(allowed) && strcmp(allowed, ".")) {
1374	warning(_("safe.directory '%s' not absolute"),
1375	allowed);
1376	goto next;
1377	}
1378
1379	/*
1380	* A .gitconfig in $HOME may be shared across
1381	* different machines and safe.directory entries
1382	* may or may not exist as paths on all of these
1383	* machines. In other words, it is not a warning
1384	* worthy event when there is no such path on this
1385	* machine---the entry may be useful elsewhere.
1386	*/
1387	normalized = real_pathdup(allowed, 0);
1388	if (!normalized)
1389	goto next;
1390
1391	if (ends_with(normalized, "/*")) {
1392	size_t len = strlen(normalized);
1393	if (!fspathncmp(normalized, data->path, len - 1))
1394	data->is_safe = 1;
1395	} else if (!fspathcmp(data->path, normalized)) {
1396	data->is_safe = 1;
1397	}
1398	next:
1399	free(normalized);
1400	free(allowed);
1401	}
1402	}
1403
1404	return 0;
1405	}
1406
1407	/*
1408	* Check if a repository is safe, by verifying the ownership of the
1409	* worktree (if any), the git directory, and the gitfile (if any).
1410	*
1411	* Exemptions for known-safe repositories can be added via `safe.directory`
1412	* config settings; for non-bare repositories, their worktree needs to be
1413	* added, for bare ones their git directory.
1414	*/
1415	static int ensure_valid_ownership(const char *gitfile,
1416	const char worktree, const char gitdir,
1417	struct strbuf *report)
1418	{
1419	struct safe_directory_data data = { 0 };
1420
1421	if (!git_env_bool("GIT_TEST_ASSUME_DIFFERENT_OWNER", 0) &&
1422	(!gitfile \|\| is_path_owned_by_current_user(gitfile, report)) &&
1423	(!worktree \|\| is_path_owned_by_current_user(worktree, report)) &&
1424	(!gitdir \|\| is_path_owned_by_current_user(gitdir, report)))
1425	return 1;
1426
1427	/*
1428	* normalize the data.path for comparison with normalized paths
1429	* that come from the configuration file. The path is unsafe
1430	* if it cannot be normalized.
1431	*/
1432	data.path = real_pathdup(worktree ? worktree : gitdir, 0);
1433	if (!data.path)
1434	return 0;
1435
1436	/*
1437	* data.path is the "path" that identifies the repository and it is
1438	* constant regardless of what failed above. data.is_safe should be
1439	* initialized to false, and might be changed by the callback.
1440	*/
1441	git_protected_config(safe_directory_cb, &data);
1442
1443	free(data.path);
1444	return data.is_safe;
1445	}
1446
1447	void die_upon_dubious_ownership(const char gitfile, const char worktree,
1448	const char *gitdir)
1449	{
1450	struct strbuf report = STRBUF_INIT, quoted = STRBUF_INIT;
1451	const char *path;
1452
1453	if (ensure_valid_ownership(gitfile, worktree, gitdir, &report))
1454	return;
1455
1456	strbuf_complete(&report, '\n');
1457	path = gitfile ? gitfile : gitdir;
1458	sq_quote_buf_pretty(&quoted, path);
1459
1460	die(_("detected dubious ownership in repository at '%s'\n"
1461	"%s"
1462	"To add an exception for this directory, call:\n"
1463	"\n"
1464	"\tgit config --global --add safe.directory %s"),
1465	path, report.buf, quoted.buf);
1466	}
1467
1468	static int allowed_bare_repo_cb(const char key, const char value,
1469	const struct config_context *ctx UNUSED,
1470	void *d)
1471	{
1472	enum allowed_bare_repo *allowed_bare_repo = d;
1473
1474	if (strcasecmp(key, "safe.bareRepository"))
1475	return 0;
1476
1477	if (!strcmp(value, "explicit")) {
1478	*allowed_bare_repo = ALLOWED_BARE_REPO_EXPLICIT;
1479	return 0;
1480	}
1481	if (!strcmp(value, "all")) {
1482	*allowed_bare_repo = ALLOWED_BARE_REPO_ALL;
1483	return 0;
1484	}
1485	return -1;
1486	}
1487
1488	static enum allowed_bare_repo get_allowed_bare_repo(void)
1489	{
1490	#ifdef WITH_BREAKING_CHANGES
1491	enum allowed_bare_repo result = ALLOWED_BARE_REPO_EXPLICIT;
1492	#else
1493	enum allowed_bare_repo result = ALLOWED_BARE_REPO_ALL;
1494	#endif
1495	git_protected_config(allowed_bare_repo_cb, &result);
1496	return result;
1497	}
1498
1499	static const char *allowed_bare_repo_to_string(
1500	enum allowed_bare_repo allowed_bare_repo)
1501	{
1502	switch (allowed_bare_repo) {
1503	case ALLOWED_BARE_REPO_EXPLICIT:
1504	return "explicit";
1505	case ALLOWED_BARE_REPO_ALL:
1506	return "all";
1507	default:
1508	BUG("invalid allowed_bare_repo %d",
1509	allowed_bare_repo);
1510	}
1511	return NULL;
1512	}
1513
1514	static int is_implicit_bare_repo(const char *path)
1515	{
1516	/*
1517	* what we found is a ".git" directory at the root of
1518	* the working tree.
1519	*/
1520	if (ends_with_path_components(path, ".git"))
1521	return 1;
1522
1523	/*
1524	* we are inside $GIT_DIR of a secondary worktree of a
1525	* non-bare repository.
1526	*/
1527	if (strstr(path, "/.git/worktrees/"))
1528	return 1;
1529
1530	/*
1531	* we are inside $GIT_DIR of a worktree of a non-embedded
1532	* submodule, whose superproject is not a bare repository.
1533	*/
1534	if (strstr(path, "/.git/modules/"))
1535	return 1;
1536
1537	return 0;
1538	}
1539
1540	/*
1541	* We cannot decide in this function whether we are in the work tree or
1542	* not, since the config can only be read _after_ this function was called.
1543	*
1544	* Also, we avoid changing any global state (such as the current working
1545	* directory) to allow early callers.
1546	*
1547	* The directory where the search should start needs to be passed in via the
1548	* `dir` parameter; upon return, the `dir` buffer will contain the path of
1549	* the directory where the search ended, and `gitdir` will contain the path of
1550	* the discovered .git/ directory, if any. If `gitdir` is not absolute, it
1551	* is relative to `dir` (i.e. not necessarily the cwd).
1552	*/
1553	static enum discovery_result repo_discovery_find_dir(struct strbuf *dir,
1554	struct strbuf *gitdir,
1555	struct strbuf *report,
1556	int die_on_error)
1557	{
1558	const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
1559	struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
1560	const char *gitdirenv;
1561	int ceil_offset = -1, min_offset = offset_1st_component(dir->buf);
1562	dev_t current_device = 0;
1563	int one_filesystem = 1;
1564
1565	/*
1566	* If GIT_DIR is set explicitly, we're not going
1567	* to do any discovery, but we still do repository
1568	* validation.
1569	*/
1570	gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
1571	if (gitdirenv) {
1572	strbuf_addstr(gitdir, gitdirenv);
1573	return GIT_DIR_EXPLICIT;
1574	}
1575
1576	if (env_ceiling_dirs) {
1577	int empty_entry_found = 0;
1578	static const char path_sep[] = { PATH_SEP, '\0' };
1579
1580	string_list_split(&ceiling_dirs, env_ceiling_dirs, path_sep, -1);
1581	filter_string_list(&ceiling_dirs, 0,
1582	canonicalize_ceiling_entry, &empty_entry_found);
1583	ceil_offset = longest_ancestor_length(dir->buf, &ceiling_dirs);
1584	string_list_clear(&ceiling_dirs, 0);
1585	}
1586
1587	if (ceil_offset < 0)
1588	ceil_offset = min_offset - 2;
1589
1590	if (min_offset && min_offset == dir->len &&
1591	!is_dir_sep(dir->buf[min_offset - 1])) {
1592	strbuf_addch(dir, '/');
1593	min_offset++;
1594	}
1595
1596	/*
1597	* Test in the following order (relative to the dir):
1598	* - .git (file containing "gitdir: <path>")
1599	* - .git/
1600	* - ./ (bare)
1601	* - ../.git
1602	* - ../.git/
1603	* - ../ (bare)
1604	* - ../../.git
1605	* etc.
1606	*/
1607	one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
1608	if (one_filesystem)
1609	current_device = get_device_or_die(dir->buf, NULL, 0);
1610	for (;;) {
1611	int offset = dir->len, error_code = 0;
1612	char *gitdir_path = NULL;
1613	char *gitfile = NULL;
1614
1615	if (offset > min_offset)
1616	strbuf_addch(dir, '/');
1617	strbuf_addstr(dir, DEFAULT_GIT_DIR_ENVIRONMENT);
1618	gitdirenv = read_gitfile_gently(dir->buf, &error_code);
1619	if (!gitdirenv) {
1620	switch (error_code) {
1621	case READ_GITFILE_ERR_MISSING:
1622	/* no .git in this directory, move on */
1623	break;
1624	case READ_GITFILE_ERR_IS_A_DIR:
1625	if (is_git_directory(dir->buf)) {
1626	gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
1627	gitdir_path = xstrdup(dir->buf);
1628	}
1629	break;
1630	case READ_GITFILE_ERR_STAT_FAILED:
1631	if (die_on_error)
1632	die(_("error reading '%s'"), dir->buf);
1633	else
1634	return GIT_DIR_INVALID_GITFILE;
1635	case READ_GITFILE_ERR_NOT_A_FILE:
1636	if (die_on_error)
1637	die(_("not a regular file: '%s'"), dir->buf);
1638	else
1639	return GIT_DIR_INVALID_GITFILE;
1640	default:
1641	if (die_on_error)
1642	read_gitfile_error_die(error_code, dir->buf);
1643	else
1644	return GIT_DIR_INVALID_GITFILE;
1645	}
1646	} else {
1647	gitfile = xstrdup(dir->buf);
1648	}
1649	/*
1650	* Earlier, we tentatively added DEFAULT_GIT_DIR_ENVIRONMENT
1651	* to check that directory for a repository.
1652	* Now trim that tentative addition away, because we want to
1653	* focus on the real directory we are in.
1654	*/
1655	strbuf_setlen(dir, offset);
1656	if (gitdirenv) {
1657	enum discovery_result ret;
1658	const char *gitdir_candidate =
1659	gitdir_path ? gitdir_path : gitdirenv;
1660
1661	if (ensure_valid_ownership(gitfile, dir->buf,
1662	gitdir_candidate, report)) {
1663	strbuf_addstr(gitdir, gitdirenv);
1664	ret = GIT_DIR_DISCOVERED;
1665	} else
1666	ret = GIT_DIR_INVALID_OWNERSHIP;
1667
1668	/*
1669	* Earlier, during discovery, we might have allocated
1670	* string copies for gitdir_path or gitfile so make
1671	* sure we don't leak by freeing them now, before
1672	* leaving the loop and function.
1673	*
1674	* Note: gitdirenv will be non-NULL whenever these are
1675	* allocated, therefore we need not take care of releasing
1676	* them outside of this conditional block.
1677	*/
1678	free(gitdir_path);
1679	free(gitfile);
1680
1681	return ret;
1682	}
1683
1684	if (is_git_directory(dir->buf)) {
1685	trace2_data_string("setup", NULL, "implicit-bare-repository", dir->buf);
1686	if (get_allowed_bare_repo() == ALLOWED_BARE_REPO_EXPLICIT &&
1687	!is_implicit_bare_repo(dir->buf))
1688	return GIT_DIR_DISALLOWED_BARE;
1689	if (!ensure_valid_ownership(NULL, NULL, dir->buf, report))
1690	return GIT_DIR_INVALID_OWNERSHIP;
1691	strbuf_addstr(gitdir, ".");
1692	return GIT_DIR_BARE;
1693	}
1694
1695	if (offset <= min_offset)
1696	return GIT_DIR_HIT_CEILING;
1697
1698	while (--offset > ceil_offset && !is_dir_sep(dir->buf[offset]))
1699	; /* continue */
1700	if (offset <= ceil_offset)
1701	return GIT_DIR_HIT_CEILING;
1702
1703	strbuf_setlen(dir, offset > min_offset ? offset : min_offset);
1704	if (one_filesystem &&
1705	current_device != get_device_or_die(dir->buf, NULL, offset))
1706	return GIT_DIR_HIT_MOUNT_POINT;
1707	}
1708	}
1709
1710	enum discovery_result discover_git_directory_reason(struct strbuf *commondir,
1711	struct strbuf *gitdir)
1712	{
1713	struct strbuf dir = STRBUF_INIT, err = STRBUF_INIT;
1714	size_t gitdir_offset = gitdir->len, cwd_len;
1715	size_t commondir_offset = commondir->len;
1716	struct repository_format candidate = REPOSITORY_FORMAT_INIT;
1717	enum discovery_result result;
1718
1719	if (strbuf_getcwd(&dir))
1720	return GIT_DIR_CWD_FAILURE;
1721
1722	cwd_len = dir.len;
1723	result = repo_discovery_find_dir(&dir, gitdir, NULL, 0);
1724	if (result <= 0) {
1725	strbuf_release(&dir);
1726	return result;
1727	}
1728
1729	/*
1730	* The returned gitdir is relative to dir, and if dir does not reflect
1731	* the current working directory, we simply make the gitdir absolute.
1732	*/
1733	if (dir.len < cwd_len && !is_absolute_path(gitdir->buf + gitdir_offset)) {
1734	/* Avoid a trailing "/." */
1735	if (!strcmp(".", gitdir->buf + gitdir_offset))
1736	strbuf_setlen(gitdir, gitdir_offset);
1737	else
1738	strbuf_addch(&dir, '/');
1739	strbuf_insert(gitdir, gitdir_offset, dir.buf, dir.len);
1740	}
1741
1742	get_common_dir(commondir, gitdir->buf + gitdir_offset);
1743
1744	strbuf_reset(&dir);
1745	strbuf_addf(&dir, "%s/config", commondir->buf + commondir_offset);
1746	read_repository_format(&candidate, dir.buf);
1747	strbuf_release(&dir);
1748
1749	if (verify_repository_format(&candidate, &err) < 0) {
1750	warning("ignoring git dir '%s': %s",
1751	gitdir->buf + gitdir_offset, err.buf);
1752	strbuf_release(&err);
1753	strbuf_setlen(commondir, commondir_offset);
1754	strbuf_setlen(gitdir, gitdir_offset);
1755	clear_repository_format(&candidate);
1756	return GIT_DIR_INVALID_FORMAT;
1757	}
1758
1759	clear_repository_format(&candidate);
1760	return result;
1761	}
1762
1763	static void get_object_directories(char **object_directory,
1764	char **alternate_object_directories)
1765	{
1766	*object_directory = xstrdup_or_null(getenv(DB_ENVIRONMENT));
1767	*alternate_object_directories = xstrdup_or_null(getenv(ALTERNATE_DB_ENVIRONMENT));
1768	}
1769
1770	int apply_repository_format(struct repository *repo,
1771	const struct repository_format *format,
1772	enum apply_repository_format_flags flags,
1773	struct strbuf *err)
1774	{
1775	char object_directory = NULL, alternate_object_directories = NULL;
1776
1777	if (verify_repository_format(format, err) < 0)
1778	return -1;
1779
1780	if (format->is_bare > 0 && format->work_tree) {
1781	/* #22.2, #30 */
1782	warning("core.bare and core.worktree do not make sense");
1783	repo->worktree_config_is_bogus = true;
1784	}
1785
1786	if (flags & APPLY_REPOSITORY_FORMAT_HONOR_ENV) {
1787	const char *shallow_file;
1788
1789	get_object_directories(&object_directory,
1790	&alternate_object_directories);
1791
1792	shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
1793	if (shallow_file)
1794	set_alternate_shallow_file(repo, shallow_file);
1795	}
1796
1797	repo->bare_cfg = format->is_bare;
1798	repo_set_hash_algo(repo, format->hash_algo);
1799	repo_set_compat_hash_algo(repo, format->compat_hash_algo);
1800	repo_set_ref_storage_format(repo,
1801	format->ref_storage_format,
1802	format->ref_storage_payload);
1803	repo->repository_format_worktree_config =
1804	format->worktree_config;
1805	repo->repository_format_submodule_path_cfg =
1806	format->submodule_path_cfg;
1807	repo->repository_format_relative_worktrees =
1808	format->relative_worktrees;
1809	repo->repository_format_partial_clone =
1810	xstrdup_or_null(format->partial_clone);
1811	repo->repository_format_precious_objects =
1812	format->precious_objects;
1813
1814	if (!(flags & APPLY_REPOSITORY_FORMAT_SKIP_ODB_CREATION))
1815	repo->objects = odb_new(repo, object_directory,
1816	alternate_object_directories);
1817
1818	free(alternate_object_directories);
1819	free(object_directory);
1820	return 0;
1821	}
1822
1823	const char enter_repo(struct repository repo, const char *path, unsigned flags)
1824	{
1825	static struct strbuf validated_path = STRBUF_INIT;
1826	static struct strbuf used_path = STRBUF_INIT;
1827
1828	if (!path)
1829	return NULL;
1830
1831	if (!(flags & ENTER_REPO_STRICT)) {
1832	static const char *suffix[] = {
1833	"/.git", "", ".git/.git", ".git", NULL,
1834	};
1835	const char *gitfile;
1836	int len = strlen(path);
1837	int i;
1838	while ((1 < len) && (path[len-1] == '/'))
1839	len--;
1840
1841	/*
1842	* We can handle arbitrary-sized buffers, but this remains as a
1843	* sanity check on untrusted input.
1844	*/
1845	if (PATH_MAX <= len)
1846	return NULL;
1847
1848	strbuf_reset(&used_path);
1849	strbuf_reset(&validated_path);
1850	strbuf_add(&used_path, path, len);
1851	strbuf_add(&validated_path, path, len);
1852
1853	if (used_path.buf[0] == '~') {
1854	char *newpath = interpolate_path(used_path.buf, 0);
1855	if (!newpath)
1856	return NULL;
1857	strbuf_attach(&used_path, newpath, strlen(newpath),
1858	strlen(newpath));
1859	}
1860	for (i = 0; suffix[i]; i++) {
1861	struct stat st;
1862	size_t baselen = used_path.len;
1863	strbuf_addstr(&used_path, suffix[i]);
1864	if (!stat(used_path.buf, &st) &&
1865	(S_ISREG(st.st_mode) \|\|
1866	(S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
1867	strbuf_addstr(&validated_path, suffix[i]);
1868	break;
1869	}
1870	strbuf_setlen(&used_path, baselen);
1871	}
1872	if (!suffix[i])
1873	return NULL;
1874	gitfile = read_gitfile(used_path.buf);
1875	if (!(flags & ENTER_REPO_ANY_OWNER_OK))
1876	die_upon_dubious_ownership(gitfile, NULL, used_path.buf);
1877	if (gitfile) {
1878	strbuf_reset(&used_path);
1879	strbuf_addstr(&used_path, gitfile);
1880	}
1881	if (chdir(used_path.buf))
1882	return NULL;
1883	path = validated_path.buf;
1884	}
1885	else {
1886	const char *gitfile = read_gitfile(path);
1887	if (!(flags & ENTER_REPO_ANY_OWNER_OK))
1888	die_upon_dubious_ownership(gitfile, NULL, path);
1889	if (gitfile)
1890	path = gitfile;
1891	if (chdir(path))
1892	return NULL;
1893	}
1894
1895	if (is_git_directory(".")) {
1896	struct repository_format fmt = REPOSITORY_FORMAT_INIT;
1897	struct strbuf err = STRBUF_INIT;
1898
1899	apply_and_export_relative_gitdir(repo, ".", 0);
1900	read_and_verify_repository_format(&fmt, ".", NULL);
1901	if (apply_repository_format(repo, &fmt, APPLY_REPOSITORY_FORMAT_HONOR_ENV, &err) < 0)
1902	die("%s", err.buf);
1903	startup_info->have_repository = 1;
1904
1905	clear_repository_format(&fmt);
1906	strbuf_release(&err);
1907	return path;
1908	}
1909
1910	return NULL;
1911	}
1912
1913	/*
1914	* Note. This works only before you used a work tree. This was added
1915	* primarily to support git-clone to work in a new repository it just
1916	* created, and is not meant to flip between different work trees.
1917	*/
1918	static void set_git_work_tree(struct repository repo, const char new_work_tree)
1919	{
1920	if (repo->worktree_initialized) {
1921	struct strbuf realpath = STRBUF_INIT;
1922
1923	strbuf_realpath(&realpath, new_work_tree, 1);
1924	new_work_tree = realpath.buf;
1925	if (strcmp(new_work_tree, repo->worktree))
1926	die("internal error: work tree has already been set\n"
1927	"Current worktree: %s\nNew worktree: %s",
1928	repo->worktree, new_work_tree);
1929	strbuf_release(&realpath);
1930	return;
1931	}
1932	repo->worktree_initialized = true;
1933	repo_set_worktree(repo, new_work_tree);
1934	}
1935
1936	static void repo_discover(struct repo_discovery discovery, int nongit_ok)
1937	{
1938	struct strbuf cwd = STRBUF_INIT;
1939	struct strbuf dir = STRBUF_INIT, gitdir = STRBUF_INIT, report = STRBUF_INIT;
1940
1941	/*
1942	* Let's assume that we are in a git repository.
1943	* If it turns out later that we are somewhere else, the value will be
1944	* updated accordingly.
1945	*/
1946	if (nongit_ok)
1947	*nongit_ok = 0;
1948
1949	if (strbuf_getcwd(&cwd))
1950	die_errno(_("Unable to read current working directory"));
1951	strbuf_addbuf(&dir, &cwd);
1952
1953	switch (repo_discovery_find_dir(&dir, &gitdir, &report, 1)) {
1954	case GIT_DIR_EXPLICIT:
1955	repo_discover_explicit_gitdir(discovery, gitdir.buf, &cwd,
1956	nongit_ok);
1957	break;
1958	case GIT_DIR_DISCOVERED:
1959	if (dir.len < cwd.len && chdir(dir.buf))
1960	die(_("cannot change to '%s'"), dir.buf);
1961	repo_discover_implicit_gitdir(discovery, gitdir.buf, &cwd, dir.len,
1962	nongit_ok);
1963	break;
1964	case GIT_DIR_BARE:
1965	if (dir.len < cwd.len && chdir(dir.buf))
1966	die(_("cannot change to '%s'"), dir.buf);
1967	repo_discover_bare_gitdir(discovery, &cwd, dir.len, nongit_ok);
1968	break;
1969	case GIT_DIR_HIT_CEILING:
1970	if (!nongit_ok)
1971	die(_("not a git repository (or any of the parent directories): %s"),
1972	DEFAULT_GIT_DIR_ENVIRONMENT);
1973	*nongit_ok = 1;
1974	break;
1975	case GIT_DIR_HIT_MOUNT_POINT:
1976	if (!nongit_ok)
1977	die(_("not a git repository (or any parent up to mount point %s)\n"
1978	"Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set)."),
1979	dir.buf);
1980	*nongit_ok = 1;
1981	break;
1982	case GIT_DIR_INVALID_OWNERSHIP:
1983	if (!nongit_ok) {
1984	struct strbuf quoted = STRBUF_INIT;
1985
1986	strbuf_complete(&report, '\n');
1987	sq_quote_buf_pretty(&quoted, dir.buf);
1988	die(_("detected dubious ownership in repository at '%s'\n"
1989	"%s"
1990	"To add an exception for this directory, call:\n"
1991	"\n"
1992	"\tgit config --global --add safe.directory %s"),
1993	dir.buf, report.buf, quoted.buf);
1994	}
1995	*nongit_ok = 1;
1996	break;
1997	case GIT_DIR_DISALLOWED_BARE:
1998	if (!nongit_ok) {
1999	die(_("cannot use bare repository '%s' (safe.bareRepository is '%s')"),
2000	dir.buf,
2001	allowed_bare_repo_to_string(get_allowed_bare_repo()));
2002	}
2003	*nongit_ok = 1;
2004	break;
2005	case GIT_DIR_CWD_FAILURE:
2006	case GIT_DIR_INVALID_FORMAT:
2007	/*
2008	* As a safeguard against repo_discovery_find_dir returning
2009	* these values, fallthrough to BUG. Otherwise it is possible to
2010	* set startup_info->have_repository to 1 when we did nothing to
2011	* find a repository.
2012	*/
2013	default:
2014	BUG("unhandled repo_discovery_find_dir() result");
2015	}
2016
2017	strbuf_release(&dir);
2018	strbuf_release(&cwd);
2019	strbuf_release(&gitdir);
2020	strbuf_release(&report);
2021	}
2022
2023	const char setup_git_directory_gently(struct repository repo, int *nongit_ok)
2024	{
2025	struct repo_discovery discovery = REPO_DISCOVERY_INIT;
2026
2027	/*
2028	* We may have read an incomplete configuration before
2029	* setting-up the git directory. If so, clear the cache so
2030	* that the next queries to the configuration reload complete
2031	* configuration (including the per-repo config file that we
2032	* ignored previously).
2033	*/
2034	repo_config_clear(repo);
2035
2036	repo_discover(&discovery, nongit_ok);
2037
2038	/*
2039	* At this point, nongit_ok is stable. If it is non-NULL and points
2040	* to a non-zero value, then this means that we haven't found a
2041	* repository and that the caller expects startup_info to reflect
2042	* this.
2043	*
2044	* Regardless of the state of nongit_ok, the_repository->prefix and
2045	* the GIT_PREFIX environment variable must always match. For details
2046	* see Documentation/config/alias.adoc.
2047	*/
2048	if (nongit_ok && *nongit_ok)
2049	startup_info->have_repository = 0;
2050	else
2051	startup_info->have_repository = 1;
2052
2053	/*
2054	* Not all paths through the setup code will have recorded a gitdir
2055	* above, so in order to guarantee that the environment is in a
2056	* consistent state after setup, explicitly set up the gitdir and
2057	* environment if we have a repository.
2058	*
2059	* NEEDSWORK: currently we allow bogus GIT_DIR values to be set in some
2060	* code paths so we also need to explicitly setup the environment if
2061	* the user has set GIT_DIR. It may be beneficial to disallow bogus
2062	* GIT_DIR values at some point in the future.
2063	*/
2064	if (/* GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, GIT_DIR_BARE */
2065	startup_info->have_repository \|\|
2066	/* GIT_DIR_EXPLICIT */
2067	getenv(GIT_DIR_ENVIRONMENT)) {
2068	if (discovery.worktree)
2069	set_git_work_tree(repo, discovery.worktree);
2070
2071	if (discovery.gitdir) {
2072	apply_and_export_relative_gitdir(repo, discovery.gitdir, 0);
2073	} else {
2074	const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
2075	if (!gitdir)
2076	gitdir = DEFAULT_GIT_DIR_ENVIRONMENT;
2077	apply_gitdir_and_environment(repo, gitdir);
2078	}
2079
2080	if (startup_info->have_repository) {
2081	struct strbuf err = STRBUF_INIT;
2082	const char *ref_backend_uri;
2083
2084	/*
2085	* The env variable should override the repository config
2086	* for 'extensions.refStorage'.
2087	*/
2088	ref_backend_uri = getenv(GIT_REFERENCE_BACKEND_ENVIRONMENT);
2089	if (ref_backend_uri) {
2090	char *format;
2091
2092	free(discovery.format.ref_storage_payload);
2093
2094	parse_reference_uri(ref_backend_uri, &format, &discovery.format.ref_storage_payload);
2095	discovery.format.ref_storage_format = ref_storage_format_by_name(format);
2096	if (discovery.format.ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
2097	die(_("unknown ref storage format: '%s'"), format);
2098
2099	free(format);
2100	}
2101
2102	if (apply_repository_format(repo, &discovery.format,
2103	APPLY_REPOSITORY_FORMAT_HONOR_ENV, &err) < 0)
2104	die("%s", err.buf);
2105
2106	clear_repository_format(&discovery.format);
2107	strbuf_release(&err);
2108	}
2109	}
2110	/*
2111	* Since precompose_string_if_needed() needs to look at
2112	* the core.precomposeunicode configuration, this
2113	* has to happen after the above block that finds
2114	* out where the repository is, i.e. a preparation
2115	* for calling repo_config_get_bool().
2116	*/
2117	if (discovery.prefix) {
2118	const char *prefix = precompose_string_if_needed(discovery.prefix);
2119	repo->prefix = xstrdup(prefix);
2120	setenv(GIT_PREFIX_ENVIRONMENT, repo->prefix, 1);
2121	} else {
2122	FREE_AND_NULL(repo->prefix);
2123	setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
2124	}
2125
2126	setup_original_cwd(repo);
2127
2128	repo_discovery_release(&discovery);
2129	return repo->prefix;
2130	}
2131
2132	int git_config_perm(const char var, const char value)
2133	{
2134	int i;
2135	char *endptr;
2136
2137	if (!value)
2138	return PERM_GROUP;
2139
2140	if (!strcmp(value, "umask"))
2141	return PERM_UMASK;
2142	if (!strcmp(value, "group"))
2143	return PERM_GROUP;
2144	if (!strcmp(value, "all") \|\|
2145	!strcmp(value, "world") \|\|
2146	!strcmp(value, "everybody"))
2147	return PERM_EVERYBODY;
2148
2149	/* Parse octal numbers */
2150	i = strtol(value, &endptr, 8);
2151
2152	/* If not an octal number, maybe true/false? */
2153	if (*endptr != 0)
2154	return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
2155
2156	/*
2157	* Treat values 0, 1 and 2 as compatibility cases, otherwise it is
2158	* a chmod value to restrict to.
2159	*/
2160	switch (i) {
2161	case PERM_UMASK: /* 0 */
2162	return PERM_UMASK;
2163	case OLD_PERM_GROUP: /* 1 */
2164	return PERM_GROUP;
2165	case OLD_PERM_EVERYBODY: /* 2 */
2166	return PERM_EVERYBODY;
2167	}
2168
2169	/* A filemode value was given: 0xxx */
2170
2171	if ((i & 0600) != 0600)
2172	die(_("problem with core.sharedRepository filemode value "
2173	"(0%.3o).\nThe owner of files must always have "
2174	"read and write permissions."), i);
2175
2176	/*
2177	* Mask filemode value. Others can not get write permission.
2178	* x flags for directories are handled separately.
2179	*/
2180	return -(i & 0666);
2181	}
2182
2183	/*
2184	* Returns the "prefix", a path to the current working directory
2185	* relative to the work tree root, or NULL, if the current working
2186	* directory is not a strict subdirectory of the work tree root. The
2187	* prefix always ends with a '/' character.
2188	*/
2189	const char setup_git_directory(struct repository repo)
2190	{
2191	return setup_git_directory_gently(repo, NULL);
2192	}
2193
2194	const char resolve_gitdir_gently(const char suspect, int *return_error_code)
2195	{
2196	if (is_git_directory(suspect))
2197	return suspect;
2198	return read_gitfile_gently(suspect, return_error_code);
2199	}
2200
2201	/* if any standard file descriptor is missing open it to /dev/null */
2202	void sanitize_stdfds(void)
2203	{
2204	int fd = xopen("/dev/null", O_RDWR);
2205	while (fd < 2)
2206	fd = xdup(fd);
2207	if (fd > 2)
2208	close(fd);
2209	}
2210
2211	int daemonize(void)
2212	{
2213	#ifdef NO_POSIX_GOODIES
2214	errno = ENOSYS;
2215	return -1;
2216	#else
2217	pid_t parent_pid = getpid();
2218	pid_t child_pid = fork();
2219
2220	switch (child_pid) {
2221	case 0:
2222	/*
2223	* We're in the child process, so we take ownership of
2224	* all tempfiles.
2225	*/
2226	reassign_tempfile_ownership(parent_pid, getpid());
2227	break;
2228	case -1:
2229	die_errno(_("fork failed"));
2230	default:
2231	/*
2232	* We're in the parent process, so we drop ownership of
2233	* all tempfiles to prevent us from removing them upon
2234	* exit.
2235	*/
2236	reassign_tempfile_ownership(parent_pid, child_pid);
2237	exit(0);
2238	}
2239	if (setsid() == -1)
2240	die_errno(_("setsid failed"));
2241	close(0);
2242	close(1);
2243	close(2);
2244	sanitize_stdfds();
2245	return 0;
2246	#endif
2247	}
2248
2249	struct template_dir_cb_data {
2250	char *path;
2251	int initialized;
2252	};
2253
2254	static int template_dir_cb(const char key, const char value,
2255	const struct config_context ctx UNUSED, void d)
2256	{
2257	struct template_dir_cb_data *data = d;
2258
2259	if (strcmp(key, "init.templatedir"))
2260	return 0;
2261
2262	if (!value) {
2263	data->path = NULL;
2264	} else {
2265	char *path = NULL;
2266
2267	FREE_AND_NULL(data->path);
2268	if (!git_config_pathname(&path, key, value))
2269	data->path = path ? path : xstrdup(value);
2270	}
2271
2272	return 0;
2273	}
2274
2275	const char get_template_dir(const char option_template)
2276	{
2277	const char *template_dir = option_template;
2278
2279	if (!template_dir)
2280	template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
2281	if (!template_dir) {
2282	static struct template_dir_cb_data data;
2283
2284	if (!data.initialized) {
2285	git_protected_config(template_dir_cb, &data);
2286	data.initialized = 1;
2287	}
2288	template_dir = data.path;
2289	}
2290	if (!template_dir) {
2291	static char *dir;
2292
2293	if (!dir)
2294	dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
2295	template_dir = dir;
2296	}
2297	return template_dir;
2298	}
2299
2300	#ifdef NO_TRUSTABLE_FILEMODE
2301	#define TEST_FILEMODE 0
2302	#else
2303	#define TEST_FILEMODE 1
2304	#endif
2305
2306	#define GIT_DEFAULT_HASH_ENVIRONMENT "GIT_DEFAULT_HASH"
2307
2308	static void copy_templates_1(struct repository *repo,
2309	struct strbuf *path,
2310	struct strbuf *template_path,
2311	DIR *dir)
2312	{
2313	size_t path_baselen = path->len;
2314	size_t template_baselen = template_path->len;
2315	struct dirent *de;
2316
2317	/* Note: if ".git/hooks" file exists in the repository being
2318	* re-initialized, /etc/core-git/templates/hooks/update would
2319	* cause "git init" to fail here. I think this is sane but
2320	* it means that the set of templates we ship by default, along
2321	* with the way the namespace under .git/ is organized, should
2322	* be really carefully chosen.
2323	*/
2324	safe_create_dir(repo, path->buf, 1);
2325	while ((de = readdir(dir)) != NULL) {
2326	struct stat st_git, st_template;
2327	int exists = 0;
2328
2329	strbuf_setlen(path, path_baselen);
2330	strbuf_setlen(template_path, template_baselen);
2331
2332	if (de->d_name[0] == '.')
2333	continue;
2334	strbuf_addstr(path, de->d_name);
2335	strbuf_addstr(template_path, de->d_name);
2336	if (lstat(path->buf, &st_git)) {
2337	if (errno != ENOENT)
2338	die_errno(_("cannot stat '%s'"), path->buf);
2339	}
2340	else
2341	exists = 1;
2342
2343	if (lstat(template_path->buf, &st_template))
2344	die_errno(_("cannot stat template '%s'"), template_path->buf);
2345
2346	if (S_ISDIR(st_template.st_mode)) {
2347	DIR *subdir = opendir(template_path->buf);
2348	if (!subdir)
2349	die_errno(_("cannot opendir '%s'"), template_path->buf);
2350	strbuf_addch(path, '/');
2351	strbuf_addch(template_path, '/');
2352	copy_templates_1(repo, path, template_path, subdir);
2353	closedir(subdir);
2354	}
2355	else if (exists)
2356	continue;
2357	else if (S_ISLNK(st_template.st_mode)) {
2358	struct strbuf lnk = STRBUF_INIT;
2359	if (strbuf_readlink(&lnk, template_path->buf,
2360	st_template.st_size) < 0)
2361	die_errno(_("cannot readlink '%s'"), template_path->buf);
2362	if (symlink(lnk.buf, path->buf))
2363	die_errno(_("cannot symlink '%s' '%s'"),
2364	lnk.buf, path->buf);
2365	strbuf_release(&lnk);
2366	}
2367	else if (S_ISREG(st_template.st_mode)) {
2368	if (copy_file(repo, path->buf, template_path->buf, st_template.st_mode))
2369	die_errno(_("cannot copy '%s' to '%s'"),
2370	template_path->buf, path->buf);
2371	}
2372	else
2373	error(_("ignoring template %s"), template_path->buf);
2374	}
2375	}
2376
2377	static void copy_templates(struct repository repo, const char option_template)
2378	{
2379	const char *template_dir = get_template_dir(option_template);
2380	struct strbuf path = STRBUF_INIT;
2381	struct strbuf template_path = STRBUF_INIT;
2382	size_t template_len;
2383	struct repository_format template_format = REPOSITORY_FORMAT_INIT;
2384	struct strbuf err = STRBUF_INIT;
2385	DIR *dir;
2386	char *to_free = NULL;
2387
2388	if (!template_dir \|\| !*template_dir)
2389	return;
2390
2391	strbuf_addstr(&template_path, template_dir);
2392	strbuf_complete(&template_path, '/');
2393	template_len = template_path.len;
2394
2395	dir = opendir(template_path.buf);
2396	if (!dir) {
2397	warning(_("templates not found in %s"), template_dir);
2398	goto free_return;
2399	}
2400
2401	/* Make sure that template is from the correct vintage */
2402	strbuf_addstr(&template_path, "config");
2403	read_repository_format(&template_format, template_path.buf);
2404	strbuf_setlen(&template_path, template_len);
2405
2406	/*
2407	* No mention of version at all is OK, but anything else should be
2408	* verified.
2409	*/
2410	if (template_format.version >= 0 &&
2411	verify_repository_format(&template_format, &err) < 0) {
2412	warning(_("not copying templates from '%s': %s"),
2413	template_dir, err.buf);
2414	strbuf_release(&err);
2415	goto close_free_return;
2416	}
2417
2418	strbuf_addstr(&path, repo_get_common_dir(repo));
2419	strbuf_complete(&path, '/');
2420	copy_templates_1(repo, &path, &template_path, dir);
2421	close_free_return:
2422	closedir(dir);
2423	free_return:
2424	free(to_free);
2425	strbuf_release(&path);
2426	strbuf_release(&template_path);
2427	clear_repository_format(&template_format);
2428	}
2429
2430	/*
2431	* If the git_dir is not directly inside the working tree, then git will not
2432	* find it by default, and we need to set the worktree explicitly.
2433	*/
2434	static int needs_work_tree_config(const char git_dir, const char work_tree)
2435	{
2436	if (!strcmp(work_tree, "/") && !strcmp(git_dir, "/.git"))
2437	return 0;
2438	if (skip_prefix(git_dir, work_tree, &git_dir) &&
2439	!strcmp(git_dir, "/.git"))
2440	return 0;
2441	return 1;
2442	}
2443
2444	void initialize_repository_version(struct repository *repo,
2445	int hash_algo,
2446	enum ref_storage_format ref_storage_format,
2447	int reinit)
2448	{
2449	struct strbuf repo_version = STRBUF_INIT;
2450	int target_version = GIT_REPO_VERSION;
2451	int default_submodule_path_config = 0;
2452
2453	/*
2454	* Note that we initialize the repository version to 1 when the ref
2455	* storage format is unknown. This is on purpose so that we can add the
2456	* correct object format to the config during git-clone(1). The format
2457	* version will get adjusted by git-clone(1) once it has learned about
2458	* the remote repository's format.
2459	*/
2460	if (hash_algo != GIT_HASH_SHA1_LEGACY \|\|
2461	ref_storage_format != REF_STORAGE_FORMAT_FILES \|\|
2462	repo->ref_storage_payload)
2463	target_version = GIT_REPO_VERSION_READ;
2464
2465	if (hash_algo != GIT_HASH_SHA1_LEGACY && hash_algo != GIT_HASH_UNKNOWN)
2466	repo_config_set(repo, "extensions.objectformat",
2467	hash_algos[hash_algo].name);
2468	else if (reinit)
2469	repo_config_set_gently(repo, "extensions.objectformat", NULL);
2470
2471	if (repo->ref_storage_payload) {
2472	struct strbuf ref_uri = STRBUF_INIT;
2473
2474	strbuf_addf(&ref_uri, "%s://%s",
2475	ref_storage_format_to_name(ref_storage_format),
2476	repo->ref_storage_payload);
2477	repo_config_set(repo, "extensions.refstorage", ref_uri.buf);
2478	strbuf_release(&ref_uri);
2479	} else if (ref_storage_format != REF_STORAGE_FORMAT_FILES) {
2480	repo_config_set(repo, "extensions.refstorage",
2481	ref_storage_format_to_name(ref_storage_format));
2482	} else if (reinit) {
2483	repo_config_set_gently(repo, "extensions.refstorage", NULL);
2484	}
2485
2486	if (reinit) {
2487	struct strbuf config = STRBUF_INIT;
2488	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
2489
2490	repo_common_path_append(repo, &config, "config");
2491	read_repository_format(&repo_fmt, config.buf);
2492
2493	if (repo_fmt.v1_only_extensions.nr)
2494	target_version = GIT_REPO_VERSION_READ;
2495
2496	strbuf_release(&config);
2497	clear_repository_format(&repo_fmt);
2498	}
2499
2500	repo_config_get_bool(repo, "init.defaultSubmodulePathConfig",
2501	&default_submodule_path_config);
2502	if (default_submodule_path_config) {
2503	/* extensions.submodulepathconfig requires at least version 1 */
2504	if (target_version == 0)
2505	target_version = 1;
2506	repo_config_set(repo, "extensions.submodulepathconfig", "true");
2507	}
2508
2509	strbuf_addf(&repo_version, "%d", target_version);
2510	repo_config_set(repo, "core.repositoryformatversion", repo_version.buf);
2511
2512	strbuf_release(&repo_version);
2513	}
2514
2515	static int is_reinit(struct repository *repo)
2516	{
2517	struct strbuf buf = STRBUF_INIT;
2518	char junk[2];
2519	int ret;
2520
2521	repo_git_path_replace(repo, &buf, "HEAD");
2522	ret = !access(buf.buf, R_OK) \|\| readlink(buf.buf, junk, sizeof(junk) - 1) != -1;
2523	strbuf_release(&buf);
2524	return ret;
2525	}
2526
2527	void create_reference_database(struct repository *repo,
2528	const char *initial_branch, int quiet)
2529	{
2530	struct strbuf err = STRBUF_INIT;
2531	char *to_free = NULL;
2532	int reinit = is_reinit(repo);
2533
2534	if (ref_store_create_on_disk(get_main_ref_store(repo), 0, &err))
2535	die("failed to set up refs db: %s", err.buf);
2536
2537	/*
2538	* Point the HEAD symref to the initial branch with if HEAD does
2539	* not yet exist.
2540	*/
2541	if (!reinit) {
2542	char *ref;
2543
2544	if (!initial_branch)
2545	initial_branch = to_free =
2546	repo_default_branch_name(repo, quiet);
2547
2548	ref = xstrfmt("refs/heads/%s", initial_branch);
2549	if (check_refname_format(ref, 0) < 0)
2550	die(_("invalid initial branch name: '%s'"),
2551	initial_branch);
2552
2553	if (refs_update_symref(get_main_ref_store(repo), "HEAD", ref, NULL) < 0)
2554	exit(1);
2555	free(ref);
2556	}
2557
2558	if (reinit && initial_branch)
2559	warning(_("re-init: ignored --initial-branch=%s"),
2560	initial_branch);
2561
2562	strbuf_release(&err);
2563	free(to_free);
2564	}
2565
2566	static int create_default_files(struct repository *repo,
2567	const char *template_path,
2568	const char *original_git_dir,
2569	const struct repository_format *fmt,
2570	int init_shared_repository)
2571	{
2572	struct stat st1;
2573	struct strbuf path = STRBUF_INIT;
2574	int reinit;
2575	int filemode;
2576	const char *work_tree = repo_get_work_tree(repo);
2577
2578	/*
2579	* First copy the templates -- we might have the default
2580	* config file there, in which case we would want to read
2581	* from it after installing.
2582	*
2583	* Before reading that config, we also need to clear out any cached
2584	* values (since we've just potentially changed what's available on
2585	* disk).
2586	*/
2587	copy_templates(repo, template_path);
2588	repo_config_clear(repo);
2589	repo_settings_reset_shared_repository(repo);
2590	repo_config(repo, git_default_config, NULL);
2591
2592	reinit = is_reinit(repo);
2593
2594	/*
2595	* We must make sure command-line options continue to override any
2596	* values we might have just re-read from the config.
2597	*/
2598	if (init_shared_repository != -1)
2599	repo_settings_set_shared_repository(repo,
2600	init_shared_repository);
2601
2602	repo->bare_cfg = !work_tree;
2603
2604	/*
2605	* We would have created the above under user's umask -- under
2606	* shared-repository settings, we would need to fix them up.
2607	*/
2608	if (repo_settings_get_shared_repository(repo)) {
2609	adjust_shared_perm(repo, repo_get_git_dir(repo));
2610	}
2611
2612	initialize_repository_version(repo, fmt->hash_algo, fmt->ref_storage_format, reinit);
2613
2614	/* Check filemode trustability */
2615	repo_git_path_replace(repo, &path, "config");
2616	filemode = TEST_FILEMODE;
2617	if (TEST_FILEMODE && !lstat(path.buf, &st1)) {
2618	struct stat st2;
2619	filemode = (!chmod(path.buf, st1.st_mode ^ S_IXUSR) &&
2620	!lstat(path.buf, &st2) &&
2621	st1.st_mode != st2.st_mode &&
2622	!chmod(path.buf, st1.st_mode));
2623	if (filemode && !reinit && (st1.st_mode & S_IXUSR))
2624	filemode = 0;
2625	}
2626	repo_config_set(repo, "core.filemode", filemode ? "true" : "false");
2627
2628	if (is_bare_repository(repo))
2629	repo_config_set(repo, "core.bare", "true");
2630	else {
2631	const char *value;
2632
2633	repo_config_set(repo, "core.bare", "false");
2634
2635	/* allow template config file to override the default */
2636	if (repo_config_get_string_tmp(repo, "core.logallrefupdates", &value))
2637	repo_config_set(repo, "core.logallrefupdates", "true");
2638
2639	if (needs_work_tree_config(original_git_dir, work_tree))
2640	repo_config_set(repo, "core.worktree", work_tree);
2641	}
2642
2643	if (!reinit) {
2644	/* Check if symlink is supported in the work tree */
2645	repo_git_path_replace(repo, &path, "tXXXXXX");
2646	if (!close(xmkstemp(path.buf)) &&
2647	!unlink(path.buf) &&
2648	!symlink("testing", path.buf) &&
2649	!lstat(path.buf, &st1) &&
2650	S_ISLNK(st1.st_mode))
2651	unlink(path.buf); /* good */
2652	else
2653	repo_config_set(repo, "core.symlinks", "false");
2654
2655	/* Check if the filesystem is case-insensitive */
2656	repo_git_path_replace(repo, &path, "CoNfIg");
2657	if (!access(path.buf, F_OK))
2658	repo_config_set(repo, "core.ignorecase", "true");
2659	probe_utf8_pathname_composition();
2660	}
2661
2662	strbuf_release(&path);
2663	return reinit;
2664	}
2665
2666	static void create_object_database(struct repository *repo)
2667	{
2668	char object_directory, alternate_object_directories;
2669
2670	get_object_directories(&object_directory, &alternate_object_directories);
2671
2672	/*
2673	* Create the "objects" directory in the common directory. This is done
2674	* so that the repository can be discovered regardless of the backend
2675	* used.
2676	*
2677	* Note that we only do this in case the object directory wasn't
2678	* overwritten via an environment variable. If it _is_ being overridden
2679	* then we skip this step, as the repository won't be discoverable
2680	* anyway without the environment variable.
2681	*/
2682	if (!object_directory) {
2683	struct strbuf objects_dir = STRBUF_INIT;
2684	repo_common_path_append(repo, &objects_dir, "objects");
2685	safe_create_dir(repo, objects_dir.buf, 1);
2686	strbuf_release(&objects_dir);
2687	}
2688
2689	repo->objects = odb_new(repo, object_directory,
2690	alternate_object_directories);
2691
2692	if (odb_source_create_on_disk(repo->objects->sources) < 0)
2693	die("failed creating object database");
2694
2695	free(alternate_object_directories);
2696	free(object_directory);
2697	}
2698
2699	static void separate_git_dir(struct repository *repo,
2700	const char git_dir, const char git_link)
2701	{
2702	struct stat st;
2703
2704	if (!stat(git_link, &st)) {
2705	const char *src;
2706
2707	if (S_ISREG(st.st_mode))
2708	src = read_gitfile(git_link);
2709	else if (S_ISDIR(st.st_mode))
2710	src = git_link;
2711	else
2712	die(_("unable to handle file type %d"), (int)st.st_mode);
2713
2714	if (rename(src, git_dir))
2715	die_errno(_("unable to move %s to %s"), src, git_dir);
2716	repair_worktrees_after_gitdir_move(repo, src);
2717	}
2718
2719	write_file(git_link, "gitdir: %s", git_dir);
2720	}
2721
2722	struct default_format_config {
2723	int hash;
2724	enum ref_storage_format ref_format;
2725	};
2726
2727	static int read_default_format_config(const char key, const char value,
2728	const struct config_context *ctx UNUSED,
2729	void *payload)
2730	{
2731	struct default_format_config *cfg = payload;
2732	char *str = NULL;
2733	int ret;
2734
2735	if (!strcmp(key, "init.defaultobjectformat")) {
2736	ret = git_config_string(&str, key, value);
2737	if (ret)
2738	goto out;
2739	cfg->hash = hash_algo_by_name(str);
2740	if (cfg->hash == GIT_HASH_UNKNOWN)
2741	warning(_("unknown hash algorithm '%s'"), str);
2742	goto out;
2743	}
2744
2745	if (!strcmp(key, "init.defaultrefformat")) {
2746	ret = git_config_string(&str, key, value);
2747	if (ret)
2748	goto out;
2749	cfg->ref_format = ref_storage_format_by_name(str);
2750	if (cfg->ref_format == REF_STORAGE_FORMAT_UNKNOWN)
2751	warning(_("unknown ref storage format '%s'"), str);
2752	goto out;
2753	}
2754
2755	/*
2756	* Enable the reftable format when "features.experimental" is enabled.
2757	* "init.defaultRefFormat" takes precedence over this setting.
2758	*/
2759	if (!strcmp(key, "feature.experimental") &&
2760	cfg->ref_format == REF_STORAGE_FORMAT_UNKNOWN &&
2761	git_config_bool(key, value)) {
2762	cfg->ref_format = REF_STORAGE_FORMAT_REFTABLE;
2763	ret = 0;
2764	goto out;
2765	}
2766
2767	ret = 0;
2768	out:
2769	free(str);
2770	return ret;
2771	}
2772
2773	static void repository_format_configure(struct repository_format *repo_fmt,
2774	int hash, enum ref_storage_format ref_format)
2775	{
2776	struct default_format_config cfg = {
2777	.hash = GIT_HASH_UNKNOWN,
2778	.ref_format = REF_STORAGE_FORMAT_UNKNOWN,
2779	};
2780	struct config_options opts = {
2781	.respect_includes = 1,
2782	.ignore_repo = 1,
2783	.ignore_worktree = 1,
2784	};
2785	const char *ref_backend_uri;
2786	const char *env;
2787
2788	config_with_options(read_default_format_config, &cfg, NULL, NULL, &opts);
2789
2790	/*
2791	* If we already have an initialized repo, don't allow the user to
2792	* specify a different algorithm, as that could cause corruption.
2793	* Otherwise, if the user has specified one on the command line, use it.
2794	*/
2795	env = getenv(GIT_DEFAULT_HASH_ENVIRONMENT);
2796	if (repo_fmt->version >= 0 && hash != GIT_HASH_UNKNOWN && hash != repo_fmt->hash_algo)
2797	die(_("attempt to reinitialize repository with different hash"));
2798	else if (hash != GIT_HASH_UNKNOWN)
2799	repo_fmt->hash_algo = hash;
2800	else if (env) {
2801	int env_algo = hash_algo_by_name(env);
2802	if (env_algo == GIT_HASH_UNKNOWN)
2803	die(_("unknown hash algorithm '%s'"), env);
2804	if (repo_fmt->version < 0 \|\|
2805	repo_fmt->hash_algo == GIT_HASH_UNKNOWN)
2806	repo_fmt->hash_algo = env_algo;
2807	} else if (cfg.hash != GIT_HASH_UNKNOWN) {
2808	repo_fmt->hash_algo = cfg.hash;
2809	}
2810
2811	env = getenv("GIT_DEFAULT_REF_FORMAT");
2812	if (repo_fmt->version >= 0 &&
2813	ref_format != REF_STORAGE_FORMAT_UNKNOWN &&
2814	ref_format != repo_fmt->ref_storage_format) {
2815	die(_("attempt to reinitialize repository with different reference storage format"));
2816	} else if (ref_format != REF_STORAGE_FORMAT_UNKNOWN) {
2817	repo_fmt->ref_storage_format = ref_format;
2818	} else if (env) {
2819	ref_format = ref_storage_format_by_name(env);
2820	if (ref_format == REF_STORAGE_FORMAT_UNKNOWN)
2821	die(_("unknown ref storage format '%s'"), env);
2822	if (repo_fmt->version < 0 \|\|
2823	repo_fmt->ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
2824	repo_fmt->ref_storage_format = ref_format;
2825	} else if (cfg.ref_format != REF_STORAGE_FORMAT_UNKNOWN) {
2826	repo_fmt->ref_storage_format = cfg.ref_format;
2827	} else {
2828	repo_fmt->ref_storage_format = REF_STORAGE_FORMAT_DEFAULT;
2829	}
2830
2831
2832	ref_backend_uri = getenv(GIT_REFERENCE_BACKEND_ENVIRONMENT);
2833	if (ref_backend_uri) {
2834	char backend, payload;
2835	enum ref_storage_format format;
2836
2837	parse_reference_uri(ref_backend_uri, &backend, &payload);
2838	format = ref_storage_format_by_name(backend);
2839	if (format == REF_STORAGE_FORMAT_UNKNOWN)
2840	die(_("unknown ref storage format: '%s'"), backend);
2841
2842	repo_fmt->ref_storage_format = format;
2843	repo_fmt->ref_storage_payload = payload;
2844
2845	free(backend);
2846	}
2847	}
2848
2849	int init_db(struct repository *repo,
2850	const char *git_dir,
2851	const char *real_git_dir,
2852	const char *worktree,
2853	const char *template_dir, int hash,
2854	enum ref_storage_format ref_storage_format,
2855	const char *initial_branch,
2856	int init_shared_repository, unsigned int flags)
2857	{
2858	int reinit;
2859	int exist_ok = flags & INIT_DB_EXIST_OK;
2860	char *original_git_dir = real_pathdup(git_dir, 1);
2861	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
2862	struct strbuf err = STRBUF_INIT;
2863
2864	if (real_git_dir) {
2865	struct stat st;
2866
2867	if (!exist_ok && !stat(git_dir, &st))
2868	die(_("%s already exists"), git_dir);
2869
2870	if (!exist_ok && !stat(real_git_dir, &st))
2871	die(_("%s already exists"), real_git_dir);
2872
2873	apply_and_export_relative_gitdir(repo, real_git_dir, 1);
2874	git_dir = repo_get_git_dir(repo);
2875	separate_git_dir(repo, git_dir, original_git_dir);
2876	} else {
2877	apply_and_export_relative_gitdir(repo, git_dir, 1);
2878	git_dir = repo_get_git_dir(repo);
2879	}
2880
2881	if (worktree)
2882	set_git_work_tree(repo, worktree);
2883
2884	/*
2885	* Check to see if the repository version is right.
2886	* Note that a newly created repository does not have
2887	* config file, so this will not fail. What we are catching
2888	* is an attempt to reinitialize new repository with an old tool.
2889	*/
2890	read_and_verify_repository_format(&repo_fmt, repo_get_git_dir(repo), NULL);
2891	repository_format_configure(&repo_fmt, hash, ref_storage_format);
2892	if (apply_repository_format(repo, &repo_fmt,
2893	APPLY_REPOSITORY_FORMAT_HONOR_ENV \|
2894	APPLY_REPOSITORY_FORMAT_SKIP_ODB_CREATION, &err) < 0)
2895	die("%s", err.buf);
2896
2897	/*
2898	* Ensure `core.hidedotfiles` is processed. This must happen after we
2899	* have set up the repository format such that we can evaluate
2900	* includeIf conditions correctly in the case of re-initialization.
2901	*/
2902	repo_config(repo, git_default_core_config, NULL);
2903
2904	safe_create_dir(repo, git_dir, 0);
2905
2906	reinit = create_default_files(repo, template_dir, original_git_dir,
2907	&repo_fmt, init_shared_repository);
2908
2909	if (!(flags & INIT_DB_SKIP_REFDB))
2910	create_reference_database(repo, initial_branch, flags & INIT_DB_QUIET);
2911	create_object_database(repo);
2912
2913	startup_info->have_repository = 1;
2914
2915	if (repo_settings_get_shared_repository(repo)) {
2916	char buf[10];
2917	/* We do not spell "group" and such, so that
2918	* the configuration can be read by older version
2919	* of git. Note, we use octal numbers for new share modes,
2920	* and compatibility values for PERM_GROUP and
2921	* PERM_EVERYBODY.
2922	*/
2923	if (repo_settings_get_shared_repository(repo) < 0)
2924	/* force to the mode value */
2925	xsnprintf(buf, sizeof(buf), "0%o", -repo_settings_get_shared_repository(repo));
2926	else if (repo_settings_get_shared_repository(repo) == PERM_GROUP)
2927	xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_GROUP);
2928	else if (repo_settings_get_shared_repository(repo) == PERM_EVERYBODY)
2929	xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_EVERYBODY);
2930	else
2931	BUG("invalid value for shared_repository");
2932	repo_config_set(repo, "core.sharedrepository", buf);
2933	repo_config_set(repo, "receive.denyNonFastforwards", "true");
2934	}
2935
2936	if (!(flags & INIT_DB_QUIET)) {
2937	int len = strlen(git_dir);
2938
2939	if (reinit)
2940	printf(repo_settings_get_shared_repository(repo)
2941	? _("Reinitialized existing shared Git repository in %s%s\n")
2942	: _("Reinitialized existing Git repository in %s%s\n"),
2943	git_dir, len && git_dir[len-1] != '/' ? "/" : "");
2944	else
2945	printf(repo_settings_get_shared_repository(repo)
2946	? _("Initialized empty shared Git repository in %s%s\n")
2947	: _("Initialized empty Git repository in %s%s\n"),
2948	git_dir, len && git_dir[len-1] != '/' ? "/" : "");
2949	}
2950
2951	clear_repository_format(&repo_fmt);
2952	strbuf_release(&err);
2953	free(original_git_dir);
2954	return 0;
2955	}