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

maint

bisect jch maint master next seen test todo

c 2,909 lines 79.8 KB

Raw

1	#define USE_THE_REPOSITORY_VARIABLE
2	#define DISABLE_SIGN_COMPARE_WARNINGS
3
4	#include "git-compat-util.h"
5	#include "abspath.h"
6	#include "copy.h"
7	#include "environment.h"
8	#include "exec-cmd.h"
9	#include "gettext.h"
10	#include "hex.h"
11	#include "object-file.h"
12	#include "object-name.h"
13	#include "refs.h"
14	#include "replace-object.h"
15	#include "repository.h"
16	#include "config.h"
17	#include "dir.h"
18	#include "setup.h"
19	#include "shallow.h"
20	#include "string-list.h"
21	#include "strvec.h"
22	#include "chdir-notify.h"
23	#include "path.h"
24	#include "quote.h"
25	#include "trace.h"
26	#include "trace2.h"
27	#include "worktree.h"
28
29	enum allowed_bare_repo {
30	ALLOWED_BARE_REPO_EXPLICIT = 0,
31	ALLOWED_BARE_REPO_ALL,
32	};
33
34	static struct startup_info the_startup_info;
35	struct startup_info *startup_info = &the_startup_info;
36	const char *tmp_original_cwd;
37
38	/*
39	* The input parameter must contain an absolute path, and it must already be
40	* normalized.
41	*
42	* Find the part of an absolute path that lies inside the work tree by
43	* dereferencing symlinks outside the work tree, for example:
44	* /dir1/repo/dir2/file (work tree is /dir1/repo) -> dir2/file
45	* /dir/file (work tree is /) -> dir/file
46	* /dir/symlink1/symlink2 (symlink1 points to work tree) -> symlink2
47	* /dir/repolink/file (repolink points to /dir/repo) -> file
48	* /dir/repo (exactly equal to work tree) -> (empty string)
49	*/
50	static int abspath_part_inside_repo(struct repository repo, char path)
51	{
52	size_t len;
53	size_t wtlen;
54	char *path0;
55	int off;
56	const char *work_tree = precompose_string_if_needed(repo_get_work_tree(repo));
57	struct strbuf realpath = STRBUF_INIT;
58
59	if (!work_tree)
60	return -1;
61	wtlen = strlen(work_tree);
62	len = strlen(path);
63	off = offset_1st_component(path);
64
65	/* check if work tree is already the prefix */
66	if (wtlen <= len && !fspathncmp(path, work_tree, wtlen)) {
67	if (path[wtlen] == '/') {
68	memmove(path, path + wtlen + 1, len - wtlen);
69	return 0;
70	} else if (path[wtlen - 1] == '/' \|\| path[wtlen] == '\0') {
71	/* work tree is the root, or the whole path */
72	memmove(path, path + wtlen, len - wtlen + 1);
73	return 0;
74	}
75	/* work tree might match beginning of a symlink to work tree */
76	off = wtlen;
77	}
78	path0 = path;
79	path += off;
80
81	/* check each '/'-terminated level */
82	while (*path) {
83	path++;
84	if (*path == '/') {
85	*path = '\0';
86	strbuf_realpath(&realpath, path0, 1);
87	if (fspathcmp(realpath.buf, work_tree) == 0) {
88	memmove(path0, path + 1, len - (path - path0));
89	strbuf_release(&realpath);
90	return 0;
91	}
92	*path = '/';
93	}
94	}
95
96	/* check whole path */
97	strbuf_realpath(&realpath, path0, 1);
98	if (fspathcmp(realpath.buf, work_tree) == 0) {
99	*path0 = '\0';
100	strbuf_release(&realpath);
101	return 0;
102	}
103
104	strbuf_release(&realpath);
105	return -1;
106	}
107
108	/*
109	* Normalize "path", prepending the "prefix" for relative paths. If
110	* remaining_prefix is not NULL, return the actual prefix still
111	* remains in the path. For example, prefix = sub1/sub2/ and path is
112	*
113	* foo -> sub1/sub2/foo (full prefix)
114	* ../foo -> sub1/foo (remaining prefix is sub1/)
115	* ../../bar -> bar (no remaining prefix)
116	* ../../sub1/sub2/foo -> sub1/sub2/foo (but no remaining prefix)
117	* `pwd`/../bar -> sub1/bar (no remaining prefix)
118	*/
119	char prefix_path_gently(struct repository repo,
120	const char *prefix, int len,
121	int remaining_prefix, const char path)
122	{
123	const char *orig = path;
124	char *sanitized;
125	if (is_absolute_path(orig)) {
126	sanitized = xmallocz(strlen(path));
127	if (remaining_prefix)
128	*remaining_prefix = 0;
129	if (normalize_path_copy_len(sanitized, path, remaining_prefix)) {
130	free(sanitized);
131	return NULL;
132	}
133	if (abspath_part_inside_repo(repo, sanitized)) {
134	free(sanitized);
135	return NULL;
136	}
137	} else {
138	sanitized = xstrfmt("%.*s%s", len, len ? prefix : "", path);
139	if (remaining_prefix)
140	*remaining_prefix = len;
141	if (normalize_path_copy_len(sanitized, sanitized, remaining_prefix)) {
142	free(sanitized);
143	return NULL;
144	}
145	}
146	return sanitized;
147	}
148
149	char prefix_path(struct repository repo, const char prefix, int len, const char path)
150	{
151	char *r = prefix_path_gently(repo, prefix, len, NULL, path);
152	if (!r) {
153	const char *hint_path = repo_get_work_tree(repo);
154	if (!hint_path)
155	hint_path = repo_get_git_dir(repo);
156	die(_("'%s' is outside repository at '%s'"), path,
157	absolute_path(hint_path));
158	}
159	return r;
160	}
161
162	int path_inside_repo(struct repository repo, const char prefix, const char *path)
163	{
164	int len = prefix ? strlen(prefix) : 0;
165	char *r = prefix_path_gently(repo, prefix, len, NULL, path);
166	if (r) {
167	free(r);
168	return 1;
169	}
170	return 0;
171	}
172
173	int check_filename(const char prefix, const char arg)
174	{
175	char *to_free = NULL;
176	struct stat st;
177
178	if (skip_prefix(arg, ":/", &arg)) {
179	if (!arg) / ":/" is root dir, always exists */
180	return 1;
181	prefix = NULL;
182	} else if (skip_prefix(arg, ":!", &arg) \|\|
183	skip_prefix(arg, ":^", &arg)) {
184	if (!arg) / excluding everything is silly, but allowed */
185	return 1;
186	}
187
188	if (prefix)
189	arg = to_free = prefix_filename(prefix, arg);
190
191	if (!lstat(arg, &st)) {
192	free(to_free);
193	return 1; /* file exists */
194	}
195	if (is_missing_file_error(errno)) {
196	free(to_free);
197	return 0; /* file does not exist */
198	}
199	die_errno(_("failed to stat '%s'"), arg);
200	}
201
202	static void NORETURN die_verify_filename(struct repository *r,
203	const char *prefix,
204	const char *arg,
205	int diagnose_misspelt_rev)
206	{
207	if (!diagnose_misspelt_rev)
208	die(_("%s: no such path in the working tree.\n"
209	"Use 'git <command> -- <path>...' to specify paths that do not exist locally."),
210	arg);
211	/*
212	* Saying "'(icase)foo' does not exist in the index" when the
213	* user gave us ":(icase)foo" is just stupid. A magic pathspec
214	* begins with a colon and is followed by a non-alnum; do not
215	* let maybe_die_on_misspelt_object_name() even trigger.
216	*/
217	if (!(arg[0] == ':' && !isalnum(arg[1])))
218	maybe_die_on_misspelt_object_name(r, arg, prefix);
219
220	/* ... or fall back the most general message. */
221	die(_("ambiguous argument '%s': unknown revision or path not in the working tree.\n"
222	"Use '--' to separate paths from revisions, like this:\n"
223	"'git <command> [<revision>...] -- [<file>...]'"), arg);
224
225	}
226
227	/*
228	* Check for arguments that don't resolve as actual files,
229	* but which look sufficiently like pathspecs that we'll consider
230	* them such for the purposes of rev/pathspec DWIM parsing.
231	*/
232	static int looks_like_pathspec(const char *arg)
233	{
234	const char *p;
235	int escaped = 0;
236
237	/*
238	* Wildcard characters imply the user is looking to match pathspecs
239	* that aren't in the filesystem. Note that this doesn't include
240	* backslash even though it's a glob special; by itself it doesn't
241	* cause any increase in the match. Likewise ignore backslash-escaped
242	* wildcard characters.
243	*/
244	for (p = arg; *p; p++) {
245	if (escaped) {
246	escaped = 0;
247	} else if (is_glob_special(*p)) {
248	if (*p == '\\')
249	escaped = 1;
250	else
251	return 1;
252	}
253	}
254
255	/* long-form pathspec magic */
256	if (starts_with(arg, ":("))
257	return 1;
258
259	return 0;
260	}
261
262	/*
263	* Verify a filename that we got as an argument for a pathspec
264	* entry. Note that a filename that begins with "-" never verifies
265	* as true, because even if such a filename were to exist, we want
266	* it to be preceded by the "--" marker (or we want the user to
267	* use a format like "./-filename")
268	*
269	* The "diagnose_misspelt_rev" is used to provide a user-friendly
270	* diagnosis when dying upon finding that "name" is not a pathname.
271	* If set to 1, the diagnosis will try to diagnose "name" as an
272	* invalid object name (e.g. HEAD:foo). If set to 0, the diagnosis
273	* will only complain about an inexisting file.
274	*
275	* This function is typically called to check that a "file or rev"
276	* argument is unambiguous. In this case, the caller will want
277	* diagnose_misspelt_rev == 1 when verifying the first non-rev
278	* argument (which could have been a revision), and
279	* diagnose_misspelt_rev == 0 for the next ones (because we already
280	* saw a filename, there's not ambiguity anymore).
281	*/
282	void verify_filename(struct repository *repo,
283	const char *prefix,
284	const char *arg,
285	int diagnose_misspelt_rev)
286	{
287	if (*arg == '-')
288	die(_("option '%s' must come before non-option arguments"), arg);
289	if (looks_like_pathspec(arg) \|\| check_filename(prefix, arg))
290	return;
291	die_verify_filename(repo, prefix, arg, diagnose_misspelt_rev);
292	}
293
294	/*
295	* Opposite of the above: the command line did not have -- marker
296	* and we parsed the arg as a refname. It should not be interpretable
297	* as a filename.
298	*/
299	void verify_non_filename(struct repository repo, const char prefix, const char *arg)
300	{
301	if (!is_inside_work_tree(repo) \|\| is_inside_git_dir(repo))
302	return;
303	if (*arg == '-')
304	return; /* flag */
305	if (!check_filename(prefix, arg))
306	return;
307	die(_("ambiguous argument '%s': both revision and filename\n"
308	"Use '--' to separate paths from revisions, like this:\n"
309	"'git <command> [<revision>...] -- [<file>...]'"), arg);
310	}
311
312	int get_common_dir(struct strbuf sb, const char gitdir)
313	{
314	const char *git_env_common_dir = getenv(GIT_COMMON_DIR_ENVIRONMENT);
315	if (git_env_common_dir) {
316	strbuf_addstr(sb, git_env_common_dir);
317	return 1;
318	} else {
319	return get_common_dir_noenv(sb, gitdir);
320	}
321	}
322
323	int get_common_dir_noenv(struct strbuf sb, const char gitdir)
324	{
325	struct strbuf data = STRBUF_INIT;
326	struct strbuf path = STRBUF_INIT;
327	int ret = 0;
328
329	strbuf_addf(&path, "%s/commondir", gitdir);
330	if (file_exists(path.buf)) {
331	if (strbuf_read_file(&data, path.buf, 0) <= 0)
332	die_errno(_("failed to read %s"), path.buf);
333	while (data.len && (data.buf[data.len - 1] == '\n' \|\|
334	data.buf[data.len - 1] == '\r'))
335	data.len--;
336	data.buf[data.len] = '\0';
337	strbuf_reset(&path);
338	if (!is_absolute_path(data.buf))
339	strbuf_addf(&path, "%s/", gitdir);
340	strbuf_addbuf(&path, &data);
341	strbuf_add_real_path(sb, path.buf);
342	ret = 1;
343	} else {
344	strbuf_addstr(sb, gitdir);
345	}
346
347	strbuf_release(&data);
348	strbuf_release(&path);
349	return ret;
350	}
351
352	static int validate_headref(const char *path)
353	{
354	struct stat st;
355	char buffer[256];
356	const char *refname;
357	struct object_id oid;
358	int fd;
359	ssize_t len;
360
361	if (lstat(path, &st) < 0)
362	return -1;
363
364	/* Make sure it is a "refs/.." symlink */
365	if (S_ISLNK(st.st_mode)) {
366	len = readlink(path, buffer, sizeof(buffer)-1);
367	if (len >= 5 && !memcmp("refs/", buffer, 5))
368	return 0;
369	return -1;
370	}
371
372	/*
373	* Anything else, just open it and try to see if it is a symbolic ref.
374	*/
375	fd = open(path, O_RDONLY);
376	if (fd < 0)
377	return -1;
378	len = read_in_full(fd, buffer, sizeof(buffer)-1);
379	close(fd);
380
381	if (len < 0)
382	return -1;
383	buffer[len] = '\0';
384
385	/*
386	* Is it a symbolic ref?
387	*/
388	if (skip_prefix(buffer, "ref:", &refname)) {
389	while (isspace(*refname))
390	refname++;
391	if (starts_with(refname, "refs/"))
392	return 0;
393	}
394
395	/*
396	* Is this a detached HEAD?
397	*/
398	if (get_oid_hex_any(buffer, &oid) != GIT_HASH_UNKNOWN)
399	return 0;
400
401	return -1;
402	}
403
404	/*
405	* Test if it looks like we're at a git directory.
406	* We want to see:
407	*
408	* - either an objects/ directory _or_ the proper
409	* GIT_OBJECT_DIRECTORY environment variable
410	* - a refs/ directory
411	* - either a HEAD symlink or a HEAD file that is formatted as
412	* a proper "ref:", or a regular file HEAD that has a properly
413	* formatted sha1 object name.
414	*/
415	int is_git_directory(const char *suspect)
416	{
417	struct strbuf path = STRBUF_INIT;
418	int ret = 0;
419	size_t len;
420
421	/* Check worktree-related signatures */
422	strbuf_addstr(&path, suspect);
423	strbuf_complete(&path, '/');
424	strbuf_addstr(&path, "HEAD");
425	if (validate_headref(path.buf))
426	goto done;
427
428	strbuf_reset(&path);
429	get_common_dir(&path, suspect);
430	len = path.len;
431
432	/* Check non-worktree-related signatures */
433	if (getenv(DB_ENVIRONMENT)) {
434	if (access(getenv(DB_ENVIRONMENT), X_OK))
435	goto done;
436	}
437	else {
438	strbuf_setlen(&path, len);
439	strbuf_addstr(&path, "/objects");
440	if (access(path.buf, X_OK))
441	goto done;
442	}
443
444	strbuf_setlen(&path, len);
445	strbuf_addstr(&path, "/refs");
446	if (access(path.buf, X_OK))
447	goto done;
448
449	ret = 1;
450	done:
451	strbuf_release(&path);
452	return ret;
453	}
454
455	int is_nonbare_repository_dir(struct strbuf *path)
456	{
457	int ret = 0;
458	int gitfile_error;
459	size_t orig_path_len = path->len;
460	assert(orig_path_len != 0);
461	strbuf_complete(path, '/');
462	strbuf_addstr(path, ".git");
463	if (read_gitfile_gently(path->buf, &gitfile_error) \|\| is_git_directory(path->buf))
464	ret = 1;
465	if (gitfile_error == READ_GITFILE_ERR_OPEN_FAILED \|\|
466	gitfile_error == READ_GITFILE_ERR_READ_FAILED)
467	ret = 1;
468	strbuf_setlen(path, orig_path_len);
469	return ret;
470	}
471
472	int is_inside_git_dir(struct repository *repo)
473	{
474	struct strbuf buf = STRBUF_INIT;
475	int ret = is_inside_dir(strbuf_realpath(&buf, repo_get_git_dir(repo), 1));
476	strbuf_release(&buf);
477	return ret;
478	}
479
480	int is_inside_work_tree(struct repository *repo)
481	{
482	struct strbuf buf = STRBUF_INIT;
483	const char *worktree;
484	int ret;
485
486	worktree = repo_get_work_tree(repo);
487	if (!worktree)
488	return 0;
489
490	ret = is_inside_dir(strbuf_realpath(&buf, worktree, 1));
491
492	strbuf_release(&buf);
493	return ret;
494	}
495
496	void setup_work_tree(struct repository *repo)
497	{
498	const char *work_tree;
499
500	if (repo->worktree_config_is_bogus)
501	die(_("unable to set up work tree using invalid config"));
502
503	work_tree = repo_get_work_tree(repo);
504	if (!work_tree \|\| chdir_notify(work_tree))
505	die(_("this operation must be run in a work tree"));
506
507	/*
508	* Make sure subsequent git processes find correct worktree
509	* if $GIT_WORK_TREE is set relative
510	*/
511	if (getenv(GIT_WORK_TREE_ENVIRONMENT))
512	setenv(GIT_WORK_TREE_ENVIRONMENT, ".", 1);
513	}
514
515	static void setup_original_cwd(struct repository *repo)
516	{
517	struct strbuf tmp = STRBUF_INIT;
518	const char *worktree = NULL;
519	int offset = -1;
520
521	if (!tmp_original_cwd)
522	return;
523
524	/*
525	* startup_info->original_cwd points to the current working
526	* directory we inherited from our parent process, which is a
527	* directory we want to avoid removing.
528	*
529	* For convenience, we would like to have the path relative to the
530	* worktree instead of an absolute path.
531	*
532	* Yes, startup_info->original_cwd is usually the same as 'prefix',
533	* but differs in two ways:
534	* - prefix has a trailing '/'
535	* - if the user passes '-C' to git, that modifies the prefix but
536	* not startup_info->original_cwd.
537	*/
538
539	/* Normalize the directory */
540	if (!strbuf_realpath(&tmp, tmp_original_cwd, 0)) {
541	trace2_data_string("setup", repo,
542	"realpath-path", tmp_original_cwd);
543	trace2_data_string("setup", repo,
544	"realpath-failure", strerror(errno));
545	free((char*)tmp_original_cwd);
546	tmp_original_cwd = NULL;
547	return;
548	}
549
550	free((char*)tmp_original_cwd);
551	tmp_original_cwd = NULL;
552	startup_info->original_cwd = strbuf_detach(&tmp, NULL);
553
554	/*
555	* Get our worktree; we only protect the current working directory
556	* if it's in the worktree.
557	*/
558	worktree = repo_get_work_tree(repo);
559	if (!worktree)
560	goto no_prevention_needed;
561
562	offset = dir_inside_of(startup_info->original_cwd, worktree);
563	if (offset >= 0) {
564	/*
565	* If startup_info->original_cwd == worktree, that is already
566	* protected and we don't need original_cwd as a secondary
567	* protection measure.
568	*/
569	if (!*(startup_info->original_cwd + offset))
570	goto no_prevention_needed;
571
572	/*
573	* original_cwd was inside worktree; precompose it just as
574	* we do prefix so that built up paths will match
575	*/
576	startup_info->original_cwd = \
577	precompose_string_if_needed(startup_info->original_cwd
578	+ offset);
579	return;
580	}
581
582	no_prevention_needed:
583	free((char*)startup_info->original_cwd);
584	startup_info->original_cwd = NULL;
585	}
586
587	static int read_worktree_config(const char var, const char value,
588	const struct config_context *ctx UNUSED,
589	void *vdata)
590	{
591	struct repository_format *data = vdata;
592
593	if (strcmp(var, "core.bare") == 0) {
594	data->is_bare = git_config_bool(var, value);
595	} else if (strcmp(var, "core.worktree") == 0) {
596	if (!value)
597	return config_error_nonbool(var);
598	free(data->work_tree);
599	data->work_tree = xstrdup(value);
600	}
601	return 0;
602	}
603
604	enum extension_result {
605	EXTENSION_ERROR = -1, /* compatible with error(), etc */
606	EXTENSION_UNKNOWN = 0,
607	EXTENSION_OK = 1
608	};
609
610	/*
611	* Do not add new extensions to this function. It handles extensions which are
612	* respected even in v0-format repositories for historical compatibility.
613	*/
614	static enum extension_result handle_extension_v0(const char *var,
615	const char *value,
616	const char *ext,
617	struct repository_format *data)
618	{
619	if (!strcmp(ext, "noop")) {
620	return EXTENSION_OK;
621	} else if (!strcmp(ext, "preciousobjects")) {
622	data->precious_objects = git_config_bool(var, value);
623	return EXTENSION_OK;
624	} else if (!strcmp(ext, "partialclone")) {
625	if (!value)
626	return config_error_nonbool(var);
627	data->partial_clone = xstrdup(value);
628	return EXTENSION_OK;
629	} else if (!strcmp(ext, "worktreeconfig")) {
630	data->worktree_config = git_config_bool(var, value);
631	return EXTENSION_OK;
632	}
633
634	return EXTENSION_UNKNOWN;
635	}
636
637	static void parse_reference_uri(const char value, char *format,
638	char **payload)
639	{
640	const char *schema_end;
641
642	schema_end = strstr(value, "://");
643	if (!schema_end) {
644	*format = xstrdup(value);
645	*payload = NULL;
646	} else {
647	*format = xstrndup(value, schema_end - value);
648	*payload = xstrdup_or_null(schema_end + 3);
649	}
650	}
651
652	/*
653	* Record any new extensions in this function.
654	*/
655	static enum extension_result handle_extension(const char *var,
656	const char *value,
657	const char *ext,
658	struct repository_format *data)
659	{
660	if (!strcmp(ext, "noop-v1")) {
661	return EXTENSION_OK;
662	} else if (!strcmp(ext, "objectformat")) {
663	int format;
664
665	if (!value)
666	return config_error_nonbool(var);
667	format = hash_algo_by_name(value);
668	if (format == GIT_HASH_UNKNOWN)
669	return error(_("invalid value for '%s': '%s'"),
670	"extensions.objectformat", value);
671	data->hash_algo = format;
672	return EXTENSION_OK;
673	} else if (!strcmp(ext, "compatobjectformat")) {
674	struct string_list_item *item;
675	int format;
676
677	if (!value)
678	return config_error_nonbool(var);
679	format = hash_algo_by_name(value);
680	if (format == GIT_HASH_UNKNOWN)
681	return error(_("invalid value for '%s': '%s'"),
682	"extensions.compatobjectformat", value);
683	/* For now only support compatObjectFormat being specified once. */
684	for_each_string_list_item(item, &data->v1_only_extensions) {
685	if (!strcmp(item->string, "compatobjectformat"))
686	return error(_("'%s' already specified as '%s'"),
687	"extensions.compatobjectformat",
688	hash_algos[data->compat_hash_algo].name);
689	}
690	data->compat_hash_algo = format;
691	return EXTENSION_OK;
692	} else if (!strcmp(ext, "refstorage")) {
693	unsigned int format;
694	char *format_str;
695
696	if (!value)
697	return config_error_nonbool(var);
698
699	parse_reference_uri(value, &format_str,
700	&data->ref_storage_payload);
701
702	format = ref_storage_format_by_name(format_str);
703	free(format_str);
704
705	if (format == REF_STORAGE_FORMAT_UNKNOWN)
706	return error(_("invalid value for '%s': '%s'"),
707	"extensions.refstorage", value);
708	data->ref_storage_format = format;
709	return EXTENSION_OK;
710	} else if (!strcmp(ext, "relativeworktrees")) {
711	data->relative_worktrees = git_config_bool(var, value);
712	return EXTENSION_OK;
713	} else if (!strcmp(ext, "submodulepathconfig")) {
714	data->submodule_path_cfg = git_config_bool(var, value);
715	return EXTENSION_OK;
716	}
717	return EXTENSION_UNKNOWN;
718	}
719
720	static int check_repo_format(const char var, const char value,
721	const struct config_context ctx, void vdata)
722	{
723	struct repository_format *data = vdata;
724	const char *ext;
725
726	if (strcmp(var, "core.repositoryformatversion") == 0)
727	data->version = git_config_int(var, value, ctx->kvi);
728	else if (skip_prefix(var, "extensions.", &ext)) {
729	switch (handle_extension_v0(var, value, ext, data)) {
730	case EXTENSION_ERROR:
731	return -1;
732	case EXTENSION_OK:
733	return 0;
734	case EXTENSION_UNKNOWN:
735	break;
736	}
737
738	switch (handle_extension(var, value, ext, data)) {
739	case EXTENSION_ERROR:
740	return -1;
741	case EXTENSION_OK:
742	string_list_append(&data->v1_only_extensions, ext);
743	return 0;
744	case EXTENSION_UNKNOWN:
745	string_list_append(&data->unknown_extensions, ext);
746	return 0;
747	}
748	}
749
750	return read_worktree_config(var, value, ctx, vdata);
751	}
752
753	static int check_repository_format_gently(const char *gitdir,
754	struct repository_format *candidate,
755	int *nongit_ok)
756	{
757	struct strbuf sb = STRBUF_INIT;
758	struct strbuf err = STRBUF_INIT;
759	int has_common;
760
761	has_common = get_common_dir(&sb, gitdir);
762	strbuf_addstr(&sb, "/config");
763	read_repository_format(candidate, sb.buf);
764	strbuf_release(&sb);
765
766	/*
767	* For historical use of check_and_apply_repository_format() in git-init,
768	* we treat a missing config as a silent "ok", even when nongit_ok
769	* is unset.
770	*/
771	if (candidate->version < 0)
772	return 0;
773
774	if (verify_repository_format(candidate, &err) < 0) {
775	if (nongit_ok) {
776	warning("%s", err.buf);
777	strbuf_release(&err);
778	*nongit_ok = -1;
779	return -1;
780	}
781	die("%s", err.buf);
782	}
783
784	string_list_clear(&candidate->unknown_extensions, 0);
785	string_list_clear(&candidate->v1_only_extensions, 0);
786
787	if (candidate->worktree_config) {
788	/*
789	* pick up core.bare and core.worktree from per-worktree
790	* config if present
791	*/
792	strbuf_addf(&sb, "%s/config.worktree", gitdir);
793	git_config_from_file(read_worktree_config, sb.buf, candidate);
794	strbuf_release(&sb);
795	has_common = 0;
796	}
797
798	if (!has_common) {
799	if (candidate->is_bare != -1) {
800	is_bare_repository_cfg = candidate->is_bare;
801	}
802	if (candidate->work_tree) {
803	free(git_work_tree_cfg);
804	git_work_tree_cfg = xstrdup(candidate->work_tree);
805	}
806	}
807
808	return 0;
809	}
810
811	int upgrade_repository_format(struct repository *repo, int target_version)
812	{
813	struct strbuf sb = STRBUF_INIT;
814	struct strbuf err = STRBUF_INIT;
815	struct strbuf repo_version = STRBUF_INIT;
816	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
817	int ret;
818
819	repo_common_path_append(repo, &sb, "config");
820	read_repository_format(&repo_fmt, sb.buf);
821	strbuf_release(&sb);
822
823	if (repo_fmt.version >= target_version) {
824	ret = 0;
825	goto out;
826	}
827
828	if (verify_repository_format(&repo_fmt, &err) < 0) {
829	ret = error("cannot upgrade repository format from %d to %d: %s",
830	repo_fmt.version, target_version, err.buf);
831	goto out;
832	}
833	if (!repo_fmt.version && repo_fmt.unknown_extensions.nr) {
834	ret = error("cannot upgrade repository format: "
835	"unknown extension %s",
836	repo_fmt.unknown_extensions.items[0].string);
837	goto out;
838	}
839
840	strbuf_addf(&repo_version, "%d", target_version);
841	repo_config_set(repo, "core.repositoryformatversion", repo_version.buf);
842
843	ret = 1;
844
845	out:
846	clear_repository_format(&repo_fmt);
847	strbuf_release(&repo_version);
848	strbuf_release(&err);
849	return ret;
850	}
851
852	static void init_repository_format(struct repository_format *format)
853	{
854	const struct repository_format fresh = REPOSITORY_FORMAT_INIT;
855
856	memcpy(format, &fresh, sizeof(fresh));
857	}
858
859	int read_repository_format(struct repository_format format, const char path)
860	{
861	clear_repository_format(format);
862	format->hash_algo = GIT_HASH_SHA1_LEGACY;
863	git_config_from_file(check_repo_format, path, format);
864	if (format->version == -1) {
865	clear_repository_format(format);
866	format->hash_algo = GIT_HASH_SHA1_LEGACY;
867	}
868	return format->version;
869	}
870
871	void clear_repository_format(struct repository_format *format)
872	{
873	string_list_clear(&format->unknown_extensions, 0);
874	string_list_clear(&format->v1_only_extensions, 0);
875	free(format->work_tree);
876	free(format->partial_clone);
877	free(format->ref_storage_payload);
878	init_repository_format(format);
879	}
880
881	int verify_repository_format(const struct repository_format *format,
882	struct strbuf *err)
883	{
884	if (GIT_REPO_VERSION_READ < format->version) {
885	strbuf_addf(err, _("Expected git repo version <= %d, found %d"),
886	GIT_REPO_VERSION_READ, format->version);
887	return -1;
888	}
889
890	if (format->version >= 1 && format->unknown_extensions.nr) {
891	int i;
892
893	strbuf_addstr(err, Q_("unknown repository extension found:",
894	"unknown repository extensions found:",
895	format->unknown_extensions.nr));
896
897	for (i = 0; i < format->unknown_extensions.nr; i++)
898	strbuf_addf(err, "\n\t%s",
899	format->unknown_extensions.items[i].string);
900	return -1;
901	}
902
903	if (format->version == 0 && format->v1_only_extensions.nr) {
904	int i;
905
906	strbuf_addstr(err,
907	Q_("repo version is 0, but v1-only extension found:",
908	"repo version is 0, but v1-only extensions found:",
909	format->v1_only_extensions.nr));
910
911	for (i = 0; i < format->v1_only_extensions.nr; i++)
912	strbuf_addf(err, "\n\t%s",
913	format->v1_only_extensions.items[i].string);
914	return -1;
915	}
916
917	return 0;
918	}
919
920	void read_gitfile_error_die(int error_code, const char path, const char dir)
921	{
922	switch (error_code) {
923	case READ_GITFILE_ERR_NOT_A_FILE:
924	case READ_GITFILE_ERR_STAT_FAILED:
925	case READ_GITFILE_ERR_MISSING:
926	case READ_GITFILE_ERR_IS_A_DIR:
927	/* non-fatal; follow return path */
928	break;
929	case READ_GITFILE_ERR_OPEN_FAILED:
930	die_errno(_("error opening '%s'"), path);
931	case READ_GITFILE_ERR_TOO_LARGE:
932	die(_("too large to be a .git file: '%s'"), path);
933	case READ_GITFILE_ERR_READ_FAILED:
934	die(_("error reading %s"), path);
935	case READ_GITFILE_ERR_INVALID_FORMAT:
936	die(_("invalid gitfile format: %s"), path);
937	case READ_GITFILE_ERR_NO_PATH:
938	die(_("no path in gitfile: %s"), path);
939	case READ_GITFILE_ERR_NOT_A_REPO:
940	die(_("not a git repository: %s"), dir);
941	default:
942	BUG("unknown error code");
943	}
944	}
945
946	/*
947	* Try to read the location of the git directory from the .git file,
948	* return path to git directory if found. The return value comes from
949	* a shared buffer.
950	*
951	* On failure, if return_error_code is not NULL, return_error_code
952	* will be set to an error code and NULL will be returned. If
953	* return_error_code is NULL the function will die instead (for most
954	* cases).
955	*/
956	const char read_gitfile_gently(const char path, int *return_error_code)
957	{
958	const int max_file_size = 1 << 20; /* 1MB */
959	int error_code = 0;
960	char *buf = NULL;
961	char *dir = NULL;
962	const char *slash;
963	struct stat st;
964	int fd;
965	ssize_t len;
966	static struct strbuf realpath = STRBUF_INIT;
967
968	if (stat(path, &st)) {
969	if (errno == ENOENT \|\| errno == ENOTDIR)
970	error_code = READ_GITFILE_ERR_MISSING;
971	else
972	error_code = READ_GITFILE_ERR_STAT_FAILED;
973	goto cleanup_return;
974	}
975	if (S_ISDIR(st.st_mode)) {
976	error_code = READ_GITFILE_ERR_IS_A_DIR;
977	goto cleanup_return;
978	}
979	if (!S_ISREG(st.st_mode)) {
980	error_code = READ_GITFILE_ERR_NOT_A_FILE;
981	goto cleanup_return;
982	}
983	if (st.st_size > max_file_size) {
984	error_code = READ_GITFILE_ERR_TOO_LARGE;
985	goto cleanup_return;
986	}
987	fd = open(path, O_RDONLY);
988	if (fd < 0) {
989	error_code = READ_GITFILE_ERR_OPEN_FAILED;
990	goto cleanup_return;
991	}
992	buf = xmallocz(st.st_size);
993	len = read_in_full(fd, buf, st.st_size);
994	close(fd);
995	if (len != st.st_size) {
996	error_code = READ_GITFILE_ERR_READ_FAILED;
997	goto cleanup_return;
998	}
999	if (!starts_with(buf, "gitdir: ")) {
1000	error_code = READ_GITFILE_ERR_INVALID_FORMAT;
1001	goto cleanup_return;
1002	}
1003	while (buf[len - 1] == '\n' \|\| buf[len - 1] == '\r')
1004	len--;
1005	if (len < 9) {
1006	error_code = READ_GITFILE_ERR_NO_PATH;
1007	goto cleanup_return;
1008	}
1009	buf[len] = '\0';
1010	dir = buf + 8;
1011
1012	if (!is_absolute_path(dir) && (slash = strrchr(path, '/'))) {
1013	size_t pathlen = slash+1 - path;
1014	dir = xstrfmt("%.s%.s", (int)pathlen, path,
1015	(int)(len - 8), buf + 8);
1016	free(buf);
1017	buf = dir;
1018	}
1019	if (!is_git_directory(dir)) {
1020	error_code = READ_GITFILE_ERR_NOT_A_REPO;
1021	goto cleanup_return;
1022	}
1023
1024	strbuf_realpath(&realpath, dir, 1);
1025	path = realpath.buf;
1026
1027	cleanup_return:
1028	if (return_error_code)
1029	*return_error_code = error_code;
1030	else if (error_code)
1031	read_gitfile_error_die(error_code, path, dir);
1032
1033	free(buf);
1034	return error_code ? NULL : path;
1035	}
1036
1037	static void setup_git_env_internal(struct repository *repo,
1038	const char *git_dir)
1039	{
1040	char *git_replace_ref_base;
1041	const char *shallow_file;
1042	const char *replace_ref_base;
1043	struct set_gitdir_args args = { NULL };
1044	struct strvec to_free = STRVEC_INIT;
1045
1046	args.commondir = getenv_safe(&to_free, GIT_COMMON_DIR_ENVIRONMENT);
1047	args.graft_file = getenv_safe(&to_free, GRAFT_ENVIRONMENT);
1048	args.index_file = getenv_safe(&to_free, INDEX_ENVIRONMENT);
1049	if (getenv(GIT_QUARANTINE_ENVIRONMENT))
1050	args.disable_ref_updates = true;
1051
1052	repo_set_gitdir(repo, git_dir, &args);
1053	strvec_clear(&to_free);
1054
1055	if (getenv(NO_REPLACE_OBJECTS_ENVIRONMENT))
1056	disable_replace_refs();
1057	replace_ref_base = getenv(GIT_REPLACE_REF_BASE_ENVIRONMENT);
1058	git_replace_ref_base = xstrdup(replace_ref_base ? replace_ref_base
1059	: "refs/replace/");
1060	update_ref_namespace(NAMESPACE_REPLACE, git_replace_ref_base);
1061
1062	shallow_file = getenv(GIT_SHALLOW_FILE_ENVIRONMENT);
1063	if (shallow_file)
1064	set_alternate_shallow_file(repo, shallow_file, 0);
1065
1066	if (git_env_bool(NO_LAZY_FETCH_ENVIRONMENT, 0))
1067	fetch_if_missing = 0;
1068	}
1069
1070	static void set_git_dir_1(struct repository repo, const char path)
1071	{
1072	xsetenv(GIT_DIR_ENVIRONMENT, path, 1);
1073	setup_git_env_internal(repo, path);
1074	}
1075
1076	static void update_relative_gitdir(const char *name UNUSED,
1077	const char *old_cwd,
1078	const char *new_cwd,
1079	void *data)
1080	{
1081	struct repository *repo = data;
1082	char *path = reparent_relative_path(old_cwd, new_cwd,
1083	repo_get_git_dir(repo));
1084	trace_printf_key(&trace_setup_key,
1085	"setup: move $GIT_DIR to '%s'",
1086	path);
1087	set_git_dir_1(repo, path);
1088	free(path);
1089	}
1090
1091	static void set_git_dir(struct repository repo, const char path, int make_realpath)
1092	{
1093	struct strbuf realpath = STRBUF_INIT;
1094
1095	if (make_realpath) {
1096	strbuf_realpath(&realpath, path, 1);
1097	path = realpath.buf;
1098	}
1099
1100	set_git_dir_1(repo, path);
1101	if (!is_absolute_path(path))
1102	chdir_notify_register(NULL, update_relative_gitdir, repo);
1103
1104	strbuf_release(&realpath);
1105	}
1106
1107	static const char setup_explicit_git_dir(struct repository repo,
1108	const char *gitdirenv,
1109	struct strbuf *cwd,
1110	struct repository_format *repo_fmt,
1111	int *nongit_ok)
1112	{
1113	const char *work_tree_env = getenv(GIT_WORK_TREE_ENVIRONMENT);
1114	const char *worktree;
1115	char *gitfile;
1116	int offset;
1117
1118	if (PATH_MAX - 40 < strlen(gitdirenv))
1119	die(_("'$%s' too big"), GIT_DIR_ENVIRONMENT);
1120
1121	gitfile = (char*)read_gitfile(gitdirenv);
1122	if (gitfile) {
1123	gitfile = xstrdup(gitfile);
1124	gitdirenv = gitfile;
1125	}
1126
1127	if (!is_git_directory(gitdirenv)) {
1128	if (nongit_ok) {
1129	*nongit_ok = 1;
1130	free(gitfile);
1131	return NULL;
1132	}
1133	die(_("not a git repository: '%s'"), gitdirenv);
1134	}
1135
1136	if (check_repository_format_gently(gitdirenv, repo_fmt, nongit_ok)) {
1137	free(gitfile);
1138	return NULL;
1139	}
1140
1141	/* #3, #7, #11, #15, #19, #23, #27, #31 (see t1510) */
1142	if (work_tree_env)
1143	set_git_work_tree(repo, work_tree_env);
1144	else if (is_bare_repository_cfg > 0) {
1145	if (git_work_tree_cfg) {
1146	/* #22.2, #30 */
1147	warning("core.bare and core.worktree do not make sense");
1148	repo->worktree_config_is_bogus = true;
1149	}
1150
1151	/* #18, #26 */
1152	set_git_dir(repo, gitdirenv, 0);
1153	free(gitfile);
1154	return NULL;
1155	}
1156	else if (git_work_tree_cfg) { /* #6, #14 */
1157	if (is_absolute_path(git_work_tree_cfg))
1158	set_git_work_tree(repo, git_work_tree_cfg);
1159	else {
1160	char *core_worktree;
1161	if (chdir(gitdirenv))
1162	die_errno(_("cannot chdir to '%s'"), gitdirenv);
1163	if (chdir(git_work_tree_cfg))
1164	die_errno(_("cannot chdir to '%s'"), git_work_tree_cfg);
1165	core_worktree = xgetcwd();
1166	if (chdir(cwd->buf))
1167	die_errno(_("cannot come back to cwd"));
1168	set_git_work_tree(repo, core_worktree);
1169	free(core_worktree);
1170	}
1171	}
1172	else if (!git_env_bool(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, 1)) {
1173	/* #16d */
1174	set_git_dir(repo, gitdirenv, 0);
1175	free(gitfile);
1176	return NULL;
1177	}
1178	else /* #2, #10 */
1179	set_git_work_tree(repo, ".");
1180
1181	/* set_git_work_tree() must have been called by now */
1182	worktree = repo_get_work_tree(repo);
1183
1184	/* both repo_get_work_tree() and cwd are already normalized */
1185	if (!strcmp(cwd->buf, worktree)) { /* cwd == worktree */
1186	set_git_dir(repo, gitdirenv, 0);
1187	free(gitfile);
1188	return NULL;
1189	}
1190
1191	offset = dir_inside_of(cwd->buf, worktree);
1192	if (offset >= 0) { /* cwd inside worktree? */
1193	set_git_dir(repo, gitdirenv, 1);
1194	if (chdir(worktree))
1195	die_errno(_("cannot chdir to '%s'"), worktree);
1196	strbuf_addch(cwd, '/');
1197	free(gitfile);
1198	return cwd->buf + offset;
1199	}
1200
1201	/* cwd outside worktree */
1202	set_git_dir(repo, gitdirenv, 0);
1203	free(gitfile);
1204	return NULL;
1205	}
1206
1207	static const char setup_discovered_git_dir(struct repository repo,
1208	const char *gitdir,
1209	struct strbuf *cwd, int offset,
1210	struct repository_format *repo_fmt,
1211	int *nongit_ok)
1212	{
1213	if (check_repository_format_gently(gitdir, repo_fmt, nongit_ok))
1214	return NULL;
1215
1216	/* --work-tree is set without --git-dir; use discovered one */
1217	if (getenv(GIT_WORK_TREE_ENVIRONMENT) \|\| git_work_tree_cfg) {
1218	char *to_free = NULL;
1219	const char *ret;
1220
1221	if (offset != cwd->len && !is_absolute_path(gitdir))
1222	gitdir = to_free = real_pathdup(gitdir, 1);
1223	if (chdir(cwd->buf))
1224	die_errno(_("cannot come back to cwd"));
1225	ret = setup_explicit_git_dir(repo, gitdir, cwd, repo_fmt, nongit_ok);
1226	free(to_free);
1227	return ret;
1228	}
1229
1230	/* #16.2, #17.2, #20.2, #21.2, #24, #25, #28, #29 (see t1510) */
1231	if (is_bare_repository_cfg > 0) {
1232	set_git_dir(repo, gitdir, (offset != cwd->len));
1233	if (chdir(cwd->buf))
1234	die_errno(_("cannot come back to cwd"));
1235	return NULL;
1236	}
1237
1238	/* #0, #1, #5, #8, #9, #12, #13 */
1239	set_git_work_tree(repo, ".");
1240	if (strcmp(gitdir, DEFAULT_GIT_DIR_ENVIRONMENT))
1241	set_git_dir(repo, gitdir, 0);
1242	if (offset >= cwd->len)
1243	return NULL;
1244
1245	/* Make "offset" point past the '/' (already the case for root dirs) */
1246	if (offset != offset_1st_component(cwd->buf))
1247	offset++;
1248	/* Add a '/' at the end */
1249	strbuf_addch(cwd, '/');
1250	return cwd->buf + offset;
1251	}
1252
1253	/* #16.1, #17.1, #20.1, #21.1, #22.1 (see t1510) */
1254	static const char setup_bare_git_dir(struct repository repo,
1255	struct strbuf *cwd, int offset,
1256	struct repository_format *repo_fmt,
1257	int *nongit_ok)
1258	{
1259	int root_len;
1260
1261	if (check_repository_format_gently(".", repo_fmt, nongit_ok))
1262	return NULL;
1263
1264	setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
1265
1266	/* --work-tree is set without --git-dir; use discovered one */
1267	if (getenv(GIT_WORK_TREE_ENVIRONMENT) \|\| git_work_tree_cfg) {
1268	static const char *gitdir;
1269
1270	gitdir = offset == cwd->len ? "." : xmemdupz(cwd->buf, offset);
1271	if (chdir(cwd->buf))
1272	die_errno(_("cannot come back to cwd"));
1273	return setup_explicit_git_dir(repo, gitdir, cwd, repo_fmt, nongit_ok);
1274	}
1275
1276	if (offset != cwd->len) {
1277	if (chdir(cwd->buf))
1278	die_errno(_("cannot come back to cwd"));
1279	root_len = offset_1st_component(cwd->buf);
1280	strbuf_setlen(cwd, offset > root_len ? offset : root_len);
1281	set_git_dir(repo, cwd->buf, 0);
1282	}
1283	else
1284	set_git_dir(repo, ".", 0);
1285	return NULL;
1286	}
1287
1288	static dev_t get_device_or_die(const char path, const char prefix, int prefix_len)
1289	{
1290	struct stat buf;
1291	if (stat(path, &buf)) {
1292	die_errno(_("failed to stat '%*s%s%s'"),
1293	prefix_len,
1294	prefix ? prefix : "",
1295	prefix ? "/" : "", path);
1296	}
1297	return buf.st_dev;
1298	}
1299
1300	/*
1301	* A "string_list_each_func_t" function that canonicalizes an entry
1302	* from GIT_CEILING_DIRECTORIES using real_pathdup(), or
1303	* discards it if unusable. The presence of an empty entry in
1304	* GIT_CEILING_DIRECTORIES turns off canonicalization for all
1305	* subsequent entries.
1306	*/
1307	static int canonicalize_ceiling_entry(struct string_list_item *item,
1308	void *cb_data)
1309	{
1310	int *empty_entry_found = cb_data;
1311	char *ceil = item->string;
1312
1313	if (!*ceil) {
1314	*empty_entry_found = 1;
1315	return 0;
1316	} else if (!is_absolute_path(ceil)) {
1317	return 0;
1318	} else if (*empty_entry_found) {
1319	/* Keep entry but do not canonicalize it */
1320	return 1;
1321	} else {
1322	char *real_path = real_pathdup(ceil, 0);
1323	if (!real_path) {
1324	return 0;
1325	}
1326	free(item->string);
1327	item->string = real_path;
1328	return 1;
1329	}
1330	}
1331
1332	struct safe_directory_data {
1333	char *path;
1334	int is_safe;
1335	};
1336
1337	static int safe_directory_cb(const char key, const char value,
1338	const struct config_context ctx UNUSED, void d)
1339	{
1340	struct safe_directory_data *data = d;
1341
1342	if (strcmp(key, "safe.directory"))
1343	return 0;
1344
1345	if (!value \|\| !*value) {
1346	data->is_safe = 0;
1347	} else if (!strcmp(value, "*")) {
1348	data->is_safe = 1;
1349	} else {
1350	char *allowed = NULL;
1351
1352	if (!git_config_pathname(&allowed, key, value) && allowed) {
1353	char *normalized = NULL;
1354
1355	/*
1356	* Setting safe.directory to a non-absolute path
1357	* makes little sense---it won't be relative to
1358	* the configuration file the item is defined in.
1359	* Except for ".", which means "if we are at the top
1360	* level of a repository, then it is OK", which is
1361	* slightly tighter than "*" that allows discovery.
1362	*/
1363	if (!is_absolute_path(allowed) && strcmp(allowed, ".")) {
1364	warning(_("safe.directory '%s' not absolute"),
1365	allowed);
1366	goto next;
1367	}
1368
1369	/*
1370	* A .gitconfig in $HOME may be shared across
1371	* different machines and safe.directory entries
1372	* may or may not exist as paths on all of these
1373	* machines. In other words, it is not a warning
1374	* worthy event when there is no such path on this
1375	* machine---the entry may be useful elsewhere.
1376	*/
1377	normalized = real_pathdup(allowed, 0);
1378	if (!normalized)
1379	goto next;
1380
1381	if (ends_with(normalized, "/*")) {
1382	size_t len = strlen(normalized);
1383	if (!fspathncmp(normalized, data->path, len - 1))
1384	data->is_safe = 1;
1385	} else if (!fspathcmp(data->path, normalized)) {
1386	data->is_safe = 1;
1387	}
1388	next:
1389	free(normalized);
1390	free(allowed);
1391	}
1392	}
1393
1394	return 0;
1395	}
1396
1397	/*
1398	* Check if a repository is safe, by verifying the ownership of the
1399	* worktree (if any), the git directory, and the gitfile (if any).
1400	*
1401	* Exemptions for known-safe repositories can be added via `safe.directory`
1402	* config settings; for non-bare repositories, their worktree needs to be
1403	* added, for bare ones their git directory.
1404	*/
1405	static int ensure_valid_ownership(const char *gitfile,
1406	const char worktree, const char gitdir,
1407	struct strbuf *report)
1408	{
1409	struct safe_directory_data data = { 0 };
1410
1411	if (!git_env_bool("GIT_TEST_ASSUME_DIFFERENT_OWNER", 0) &&
1412	(!gitfile \|\| is_path_owned_by_current_user(gitfile, report)) &&
1413	(!worktree \|\| is_path_owned_by_current_user(worktree, report)) &&
1414	(!gitdir \|\| is_path_owned_by_current_user(gitdir, report)))
1415	return 1;
1416
1417	/*
1418	* normalize the data.path for comparison with normalized paths
1419	* that come from the configuration file. The path is unsafe
1420	* if it cannot be normalized.
1421	*/
1422	data.path = real_pathdup(worktree ? worktree : gitdir, 0);
1423	if (!data.path)
1424	return 0;
1425
1426	/*
1427	* data.path is the "path" that identifies the repository and it is
1428	* constant regardless of what failed above. data.is_safe should be
1429	* initialized to false, and might be changed by the callback.
1430	*/
1431	git_protected_config(safe_directory_cb, &data);
1432
1433	free(data.path);
1434	return data.is_safe;
1435	}
1436
1437	void die_upon_dubious_ownership(const char gitfile, const char worktree,
1438	const char *gitdir)
1439	{
1440	struct strbuf report = STRBUF_INIT, quoted = STRBUF_INIT;
1441	const char *path;
1442
1443	if (ensure_valid_ownership(gitfile, worktree, gitdir, &report))
1444	return;
1445
1446	strbuf_complete(&report, '\n');
1447	path = gitfile ? gitfile : gitdir;
1448	sq_quote_buf_pretty(&quoted, path);
1449
1450	die(_("detected dubious ownership in repository at '%s'\n"
1451	"%s"
1452	"To add an exception for this directory, call:\n"
1453	"\n"
1454	"\tgit config --global --add safe.directory %s"),
1455	path, report.buf, quoted.buf);
1456	}
1457
1458	static int allowed_bare_repo_cb(const char key, const char value,
1459	const struct config_context *ctx UNUSED,
1460	void *d)
1461	{
1462	enum allowed_bare_repo *allowed_bare_repo = d;
1463
1464	if (strcasecmp(key, "safe.bareRepository"))
1465	return 0;
1466
1467	if (!strcmp(value, "explicit")) {
1468	*allowed_bare_repo = ALLOWED_BARE_REPO_EXPLICIT;
1469	return 0;
1470	}
1471	if (!strcmp(value, "all")) {
1472	*allowed_bare_repo = ALLOWED_BARE_REPO_ALL;
1473	return 0;
1474	}
1475	return -1;
1476	}
1477
1478	static enum allowed_bare_repo get_allowed_bare_repo(void)
1479	{
1480	#ifdef WITH_BREAKING_CHANGES
1481	enum allowed_bare_repo result = ALLOWED_BARE_REPO_EXPLICIT;
1482	#else
1483	enum allowed_bare_repo result = ALLOWED_BARE_REPO_ALL;
1484	#endif
1485	git_protected_config(allowed_bare_repo_cb, &result);
1486	return result;
1487	}
1488
1489	static const char *allowed_bare_repo_to_string(
1490	enum allowed_bare_repo allowed_bare_repo)
1491	{
1492	switch (allowed_bare_repo) {
1493	case ALLOWED_BARE_REPO_EXPLICIT:
1494	return "explicit";
1495	case ALLOWED_BARE_REPO_ALL:
1496	return "all";
1497	default:
1498	BUG("invalid allowed_bare_repo %d",
1499	allowed_bare_repo);
1500	}
1501	return NULL;
1502	}
1503
1504	static int is_implicit_bare_repo(const char *path)
1505	{
1506	/*
1507	* what we found is a ".git" directory at the root of
1508	* the working tree.
1509	*/
1510	if (ends_with_path_components(path, ".git"))
1511	return 1;
1512
1513	/*
1514	* we are inside $GIT_DIR of a secondary worktree of a
1515	* non-bare repository.
1516	*/
1517	if (strstr(path, "/.git/worktrees/"))
1518	return 1;
1519
1520	/*
1521	* we are inside $GIT_DIR of a worktree of a non-embedded
1522	* submodule, whose superproject is not a bare repository.
1523	*/
1524	if (strstr(path, "/.git/modules/"))
1525	return 1;
1526
1527	return 0;
1528	}
1529
1530	/*
1531	* We cannot decide in this function whether we are in the work tree or
1532	* not, since the config can only be read _after_ this function was called.
1533	*
1534	* Also, we avoid changing any global state (such as the current working
1535	* directory) to allow early callers.
1536	*
1537	* The directory where the search should start needs to be passed in via the
1538	* `dir` parameter; upon return, the `dir` buffer will contain the path of
1539	* the directory where the search ended, and `gitdir` will contain the path of
1540	* the discovered .git/ directory, if any. If `gitdir` is not absolute, it
1541	* is relative to `dir` (i.e. not necessarily the cwd).
1542	*/
1543	static enum discovery_result setup_git_directory_gently_1(struct strbuf *dir,
1544	struct strbuf *gitdir,
1545	struct strbuf *report,
1546	int die_on_error)
1547	{
1548	const char *env_ceiling_dirs = getenv(CEILING_DIRECTORIES_ENVIRONMENT);
1549	struct string_list ceiling_dirs = STRING_LIST_INIT_DUP;
1550	const char *gitdirenv;
1551	int ceil_offset = -1, min_offset = offset_1st_component(dir->buf);
1552	dev_t current_device = 0;
1553	int one_filesystem = 1;
1554
1555	/*
1556	* If GIT_DIR is set explicitly, we're not going
1557	* to do any discovery, but we still do repository
1558	* validation.
1559	*/
1560	gitdirenv = getenv(GIT_DIR_ENVIRONMENT);
1561	if (gitdirenv) {
1562	strbuf_addstr(gitdir, gitdirenv);
1563	return GIT_DIR_EXPLICIT;
1564	}
1565
1566	if (env_ceiling_dirs) {
1567	int empty_entry_found = 0;
1568	static const char path_sep[] = { PATH_SEP, '\0' };
1569
1570	string_list_split(&ceiling_dirs, env_ceiling_dirs, path_sep, -1);
1571	filter_string_list(&ceiling_dirs, 0,
1572	canonicalize_ceiling_entry, &empty_entry_found);
1573	ceil_offset = longest_ancestor_length(dir->buf, &ceiling_dirs);
1574	string_list_clear(&ceiling_dirs, 0);
1575	}
1576
1577	if (ceil_offset < 0)
1578	ceil_offset = min_offset - 2;
1579
1580	if (min_offset && min_offset == dir->len &&
1581	!is_dir_sep(dir->buf[min_offset - 1])) {
1582	strbuf_addch(dir, '/');
1583	min_offset++;
1584	}
1585
1586	/*
1587	* Test in the following order (relative to the dir):
1588	* - .git (file containing "gitdir: <path>")
1589	* - .git/
1590	* - ./ (bare)
1591	* - ../.git
1592	* - ../.git/
1593	* - ../ (bare)
1594	* - ../../.git
1595	* etc.
1596	*/
1597	one_filesystem = !git_env_bool("GIT_DISCOVERY_ACROSS_FILESYSTEM", 0);
1598	if (one_filesystem)
1599	current_device = get_device_or_die(dir->buf, NULL, 0);
1600	for (;;) {
1601	int offset = dir->len, error_code = 0;
1602	char *gitdir_path = NULL;
1603	char *gitfile = NULL;
1604
1605	if (offset > min_offset)
1606	strbuf_addch(dir, '/');
1607	strbuf_addstr(dir, DEFAULT_GIT_DIR_ENVIRONMENT);
1608	gitdirenv = read_gitfile_gently(dir->buf, &error_code);
1609	if (!gitdirenv) {
1610	switch (error_code) {
1611	case READ_GITFILE_ERR_MISSING:
1612	/* no .git in this directory, move on */
1613	break;
1614	case READ_GITFILE_ERR_IS_A_DIR:
1615	if (is_git_directory(dir->buf)) {
1616	gitdirenv = DEFAULT_GIT_DIR_ENVIRONMENT;
1617	gitdir_path = xstrdup(dir->buf);
1618	}
1619	break;
1620	case READ_GITFILE_ERR_STAT_FAILED:
1621	if (die_on_error)
1622	die(_("error reading '%s'"), dir->buf);
1623	else
1624	return GIT_DIR_INVALID_GITFILE;
1625	case READ_GITFILE_ERR_NOT_A_FILE:
1626	if (die_on_error)
1627	die(_("not a regular file: '%s'"), dir->buf);
1628	else
1629	return GIT_DIR_INVALID_GITFILE;
1630	default:
1631	if (die_on_error)
1632	read_gitfile_error_die(error_code, dir->buf, NULL);
1633	else
1634	return GIT_DIR_INVALID_GITFILE;
1635	}
1636	} else {
1637	gitfile = xstrdup(dir->buf);
1638	}
1639	/*
1640	* Earlier, we tentatively added DEFAULT_GIT_DIR_ENVIRONMENT
1641	* to check that directory for a repository.
1642	* Now trim that tentative addition away, because we want to
1643	* focus on the real directory we are in.
1644	*/
1645	strbuf_setlen(dir, offset);
1646	if (gitdirenv) {
1647	enum discovery_result ret;
1648	const char *gitdir_candidate =
1649	gitdir_path ? gitdir_path : gitdirenv;
1650
1651	if (ensure_valid_ownership(gitfile, dir->buf,
1652	gitdir_candidate, report)) {
1653	strbuf_addstr(gitdir, gitdirenv);
1654	ret = GIT_DIR_DISCOVERED;
1655	} else
1656	ret = GIT_DIR_INVALID_OWNERSHIP;
1657
1658	/*
1659	* Earlier, during discovery, we might have allocated
1660	* string copies for gitdir_path or gitfile so make
1661	* sure we don't leak by freeing them now, before
1662	* leaving the loop and function.
1663	*
1664	* Note: gitdirenv will be non-NULL whenever these are
1665	* allocated, therefore we need not take care of releasing
1666	* them outside of this conditional block.
1667	*/
1668	free(gitdir_path);
1669	free(gitfile);
1670
1671	return ret;
1672	}
1673
1674	if (is_git_directory(dir->buf)) {
1675	trace2_data_string("setup", NULL, "implicit-bare-repository", dir->buf);
1676	if (get_allowed_bare_repo() == ALLOWED_BARE_REPO_EXPLICIT &&
1677	!is_implicit_bare_repo(dir->buf))
1678	return GIT_DIR_DISALLOWED_BARE;
1679	if (!ensure_valid_ownership(NULL, NULL, dir->buf, report))
1680	return GIT_DIR_INVALID_OWNERSHIP;
1681	strbuf_addstr(gitdir, ".");
1682	return GIT_DIR_BARE;
1683	}
1684
1685	if (offset <= min_offset)
1686	return GIT_DIR_HIT_CEILING;
1687
1688	while (--offset > ceil_offset && !is_dir_sep(dir->buf[offset]))
1689	; /* continue */
1690	if (offset <= ceil_offset)
1691	return GIT_DIR_HIT_CEILING;
1692
1693	strbuf_setlen(dir, offset > min_offset ? offset : min_offset);
1694	if (one_filesystem &&
1695	current_device != get_device_or_die(dir->buf, NULL, offset))
1696	return GIT_DIR_HIT_MOUNT_POINT;
1697	}
1698	}
1699
1700	enum discovery_result discover_git_directory_reason(struct strbuf *commondir,
1701	struct strbuf *gitdir)
1702	{
1703	struct strbuf dir = STRBUF_INIT, err = STRBUF_INIT;
1704	size_t gitdir_offset = gitdir->len, cwd_len;
1705	size_t commondir_offset = commondir->len;
1706	struct repository_format candidate = REPOSITORY_FORMAT_INIT;
1707	enum discovery_result result;
1708
1709	if (strbuf_getcwd(&dir))
1710	return GIT_DIR_CWD_FAILURE;
1711
1712	cwd_len = dir.len;
1713	result = setup_git_directory_gently_1(&dir, gitdir, NULL, 0);
1714	if (result <= 0) {
1715	strbuf_release(&dir);
1716	return result;
1717	}
1718
1719	/*
1720	* The returned gitdir is relative to dir, and if dir does not reflect
1721	* the current working directory, we simply make the gitdir absolute.
1722	*/
1723	if (dir.len < cwd_len && !is_absolute_path(gitdir->buf + gitdir_offset)) {
1724	/* Avoid a trailing "/." */
1725	if (!strcmp(".", gitdir->buf + gitdir_offset))
1726	strbuf_setlen(gitdir, gitdir_offset);
1727	else
1728	strbuf_addch(&dir, '/');
1729	strbuf_insert(gitdir, gitdir_offset, dir.buf, dir.len);
1730	}
1731
1732	get_common_dir(commondir, gitdir->buf + gitdir_offset);
1733
1734	strbuf_reset(&dir);
1735	strbuf_addf(&dir, "%s/config", commondir->buf + commondir_offset);
1736	read_repository_format(&candidate, dir.buf);
1737	strbuf_release(&dir);
1738
1739	if (verify_repository_format(&candidate, &err) < 0) {
1740	warning("ignoring git dir '%s': %s",
1741	gitdir->buf + gitdir_offset, err.buf);
1742	strbuf_release(&err);
1743	strbuf_setlen(commondir, commondir_offset);
1744	strbuf_setlen(gitdir, gitdir_offset);
1745	clear_repository_format(&candidate);
1746	return GIT_DIR_INVALID_FORMAT;
1747	}
1748
1749	clear_repository_format(&candidate);
1750	return result;
1751	}
1752
1753	int apply_repository_format(struct repository *repo,
1754	const struct repository_format *format,
1755	enum apply_repository_format_flags flags,
1756	struct strbuf *err)
1757	{
1758	char object_directory = NULL, alternate_object_directories = NULL;
1759
1760	if (verify_repository_format(format, err) < 0)
1761	return -1;
1762
1763	if (flags & APPLY_REPOSITORY_FORMAT_HONOR_ENV) {
1764	object_directory = xstrdup_or_null(getenv(DB_ENVIRONMENT));
1765	alternate_object_directories = xstrdup_or_null(getenv(ALTERNATE_DB_ENVIRONMENT));
1766	}
1767
1768	repo_set_hash_algo(repo, format->hash_algo);
1769	repo->objects = odb_new(repo, object_directory,
1770	alternate_object_directories);
1771	repo_set_compat_hash_algo(repo, format->compat_hash_algo);
1772	repo_set_ref_storage_format(repo,
1773	format->ref_storage_format,
1774	format->ref_storage_payload);
1775	repo->repository_format_worktree_config =
1776	format->worktree_config;
1777	repo->repository_format_submodule_path_cfg =
1778	format->submodule_path_cfg;
1779	repo->repository_format_relative_worktrees =
1780	format->relative_worktrees;
1781	repo->repository_format_partial_clone =
1782	xstrdup_or_null(format->partial_clone);
1783	repo->repository_format_precious_objects =
1784	format->precious_objects;
1785
1786	free(alternate_object_directories);
1787	free(object_directory);
1788	return 0;
1789	}
1790
1791	/*
1792	* Check the repository format version in the path found in repo_get_git_dir(repo),
1793	* and die if it is a version we don't understand. Generally one would
1794	* set_git_dir() before calling this, and use it only for "are we in a valid
1795	* repo?".
1796	*
1797	* If successful and fmt is not NULL, fill fmt with data.
1798	*/
1799	static void check_and_apply_repository_format(struct repository *repo,
1800	struct repository_format *fmt,
1801	enum apply_repository_format_flags flags)
1802	{
1803	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
1804	struct strbuf err = STRBUF_INIT;
1805
1806	if (!fmt)
1807	fmt = &repo_fmt;
1808
1809	check_repository_format_gently(repo_get_git_dir(repo), fmt, NULL);
1810	if (apply_repository_format(repo, fmt, flags, &err) < 0)
1811	die("%s", err.buf);
1812	startup_info->have_repository = 1;
1813
1814	clear_repository_format(&repo_fmt);
1815	}
1816
1817	const char enter_repo(struct repository repo, const char *path, unsigned flags)
1818	{
1819	static struct strbuf validated_path = STRBUF_INIT;
1820	static struct strbuf used_path = STRBUF_INIT;
1821
1822	if (!path)
1823	return NULL;
1824
1825	if (!(flags & ENTER_REPO_STRICT)) {
1826	static const char *suffix[] = {
1827	"/.git", "", ".git/.git", ".git", NULL,
1828	};
1829	const char *gitfile;
1830	int len = strlen(path);
1831	int i;
1832	while ((1 < len) && (path[len-1] == '/'))
1833	len--;
1834
1835	/*
1836	* We can handle arbitrary-sized buffers, but this remains as a
1837	* sanity check on untrusted input.
1838	*/
1839	if (PATH_MAX <= len)
1840	return NULL;
1841
1842	strbuf_reset(&used_path);
1843	strbuf_reset(&validated_path);
1844	strbuf_add(&used_path, path, len);
1845	strbuf_add(&validated_path, path, len);
1846
1847	if (used_path.buf[0] == '~') {
1848	char *newpath = interpolate_path(used_path.buf, 0);
1849	if (!newpath)
1850	return NULL;
1851	strbuf_attach(&used_path, newpath, strlen(newpath),
1852	strlen(newpath));
1853	}
1854	for (i = 0; suffix[i]; i++) {
1855	struct stat st;
1856	size_t baselen = used_path.len;
1857	strbuf_addstr(&used_path, suffix[i]);
1858	if (!stat(used_path.buf, &st) &&
1859	(S_ISREG(st.st_mode) \|\|
1860	(S_ISDIR(st.st_mode) && is_git_directory(used_path.buf)))) {
1861	strbuf_addstr(&validated_path, suffix[i]);
1862	break;
1863	}
1864	strbuf_setlen(&used_path, baselen);
1865	}
1866	if (!suffix[i])
1867	return NULL;
1868	gitfile = read_gitfile(used_path.buf);
1869	if (!(flags & ENTER_REPO_ANY_OWNER_OK))
1870	die_upon_dubious_ownership(gitfile, NULL, used_path.buf);
1871	if (gitfile) {
1872	strbuf_reset(&used_path);
1873	strbuf_addstr(&used_path, gitfile);
1874	}
1875	if (chdir(used_path.buf))
1876	return NULL;
1877	path = validated_path.buf;
1878	}
1879	else {
1880	const char *gitfile = read_gitfile(path);
1881	if (!(flags & ENTER_REPO_ANY_OWNER_OK))
1882	die_upon_dubious_ownership(gitfile, NULL, path);
1883	if (gitfile)
1884	path = gitfile;
1885	if (chdir(path))
1886	return NULL;
1887	}
1888
1889	if (is_git_directory(".")) {
1890	set_git_dir(repo, ".", 0);
1891	check_and_apply_repository_format(repo, NULL,
1892	APPLY_REPOSITORY_FORMAT_HONOR_ENV);
1893	return path;
1894	}
1895
1896	return NULL;
1897	}
1898
1899	/*
1900	* Note. This works only before you used a work tree. This was added
1901	* primarily to support git-clone to work in a new repository it just
1902	* created, and is not meant to flip between different work trees.
1903	*/
1904	void set_git_work_tree(struct repository repo, const char new_work_tree)
1905	{
1906	if (repo->worktree_initialized) {
1907	struct strbuf realpath = STRBUF_INIT;
1908
1909	strbuf_realpath(&realpath, new_work_tree, 1);
1910	new_work_tree = realpath.buf;
1911	if (strcmp(new_work_tree, repo->worktree))
1912	die("internal error: work tree has already been set\n"
1913	"Current worktree: %s\nNew worktree: %s",
1914	repo->worktree, new_work_tree);
1915	strbuf_release(&realpath);
1916	return;
1917	}
1918	repo->worktree_initialized = true;
1919	repo_set_worktree(repo, new_work_tree);
1920	}
1921
1922	const char setup_git_directory_gently(struct repository repo, int *nongit_ok)
1923	{
1924	static struct strbuf cwd = STRBUF_INIT;
1925	struct strbuf dir = STRBUF_INIT, gitdir = STRBUF_INIT, report = STRBUF_INIT;
1926	const char *prefix = NULL;
1927	const char *ref_backend_uri;
1928	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
1929
1930	/*
1931	* We may have read an incomplete configuration before
1932	* setting-up the git directory. If so, clear the cache so
1933	* that the next queries to the configuration reload complete
1934	* configuration (including the per-repo config file that we
1935	* ignored previously).
1936	*/
1937	repo_config_clear(repo);
1938
1939	/*
1940	* Let's assume that we are in a git repository.
1941	* If it turns out later that we are somewhere else, the value will be
1942	* updated accordingly.
1943	*/
1944	if (nongit_ok)
1945	*nongit_ok = 0;
1946
1947	if (strbuf_getcwd(&cwd))
1948	die_errno(_("Unable to read current working directory"));
1949	strbuf_addbuf(&dir, &cwd);
1950
1951	switch (setup_git_directory_gently_1(&dir, &gitdir, &report, 1)) {
1952	case GIT_DIR_EXPLICIT:
1953	prefix = setup_explicit_git_dir(repo, gitdir.buf, &cwd, &repo_fmt, nongit_ok);
1954	break;
1955	case GIT_DIR_DISCOVERED:
1956	if (dir.len < cwd.len && chdir(dir.buf))
1957	die(_("cannot change to '%s'"), dir.buf);
1958	prefix = setup_discovered_git_dir(repo, gitdir.buf, &cwd, dir.len,
1959	&repo_fmt, nongit_ok);
1960	break;
1961	case GIT_DIR_BARE:
1962	if (dir.len < cwd.len && chdir(dir.buf))
1963	die(_("cannot change to '%s'"), dir.buf);
1964	prefix = setup_bare_git_dir(repo, &cwd, dir.len, &repo_fmt, nongit_ok);
1965	break;
1966	case GIT_DIR_HIT_CEILING:
1967	if (!nongit_ok)
1968	die(_("not a git repository (or any of the parent directories): %s"),
1969	DEFAULT_GIT_DIR_ENVIRONMENT);
1970	*nongit_ok = 1;
1971	break;
1972	case GIT_DIR_HIT_MOUNT_POINT:
1973	if (!nongit_ok)
1974	die(_("not a git repository (or any parent up to mount point %s)\n"
1975	"Stopping at filesystem boundary (GIT_DISCOVERY_ACROSS_FILESYSTEM not set)."),
1976	dir.buf);
1977	*nongit_ok = 1;
1978	break;
1979	case GIT_DIR_INVALID_OWNERSHIP:
1980	if (!nongit_ok) {
1981	struct strbuf quoted = STRBUF_INIT;
1982
1983	strbuf_complete(&report, '\n');
1984	sq_quote_buf_pretty(&quoted, dir.buf);
1985	die(_("detected dubious ownership in repository at '%s'\n"
1986	"%s"
1987	"To add an exception for this directory, call:\n"
1988	"\n"
1989	"\tgit config --global --add safe.directory %s"),
1990	dir.buf, report.buf, quoted.buf);
1991	}
1992	*nongit_ok = 1;
1993	break;
1994	case GIT_DIR_DISALLOWED_BARE:
1995	if (!nongit_ok) {
1996	die(_("cannot use bare repository '%s' (safe.bareRepository is '%s')"),
1997	dir.buf,
1998	allowed_bare_repo_to_string(get_allowed_bare_repo()));
1999	}
2000	*nongit_ok = 1;
2001	break;
2002	case GIT_DIR_CWD_FAILURE:
2003	case GIT_DIR_INVALID_FORMAT:
2004	/*
2005	* As a safeguard against setup_git_directory_gently_1 returning
2006	* these values, fallthrough to BUG. Otherwise it is possible to
2007	* set startup_info->have_repository to 1 when we did nothing to
2008	* find a repository.
2009	*/
2010	default:
2011	BUG("unhandled setup_git_directory_gently_1() result");
2012	}
2013
2014	/*
2015	* At this point, nongit_ok is stable. If it is non-NULL and points
2016	* to a non-zero value, then this means that we haven't found a
2017	* repository and that the caller expects startup_info to reflect
2018	* this.
2019	*
2020	* Regardless of the state of nongit_ok, startup_info->prefix and
2021	* the GIT_PREFIX environment variable must always match. For details
2022	* see Documentation/config/alias.adoc.
2023	*/
2024	if (nongit_ok && *nongit_ok)
2025	startup_info->have_repository = 0;
2026	else
2027	startup_info->have_repository = 1;
2028
2029	/*
2030	* Not all paths through the setup code will call 'set_git_dir()' (which
2031	* directly sets up the environment) so in order to guarantee that the
2032	* environment is in a consistent state after setup, explicitly setup
2033	* the environment if we have a repository.
2034	*
2035	* NEEDSWORK: currently we allow bogus GIT_DIR values to be set in some
2036	* code paths so we also need to explicitly setup the environment if
2037	* the user has set GIT_DIR. It may be beneficial to disallow bogus
2038	* GIT_DIR values at some point in the future.
2039	*/
2040	if (/* GIT_DIR_EXPLICIT, GIT_DIR_DISCOVERED, GIT_DIR_BARE */
2041	startup_info->have_repository \|\|
2042	/* GIT_DIR_EXPLICIT */
2043	getenv(GIT_DIR_ENVIRONMENT)) {
2044	if (!repo->gitdir) {
2045	const char *gitdir = getenv(GIT_DIR_ENVIRONMENT);
2046	if (!gitdir)
2047	gitdir = DEFAULT_GIT_DIR_ENVIRONMENT;
2048	setup_git_env_internal(repo, gitdir);
2049	}
2050
2051	if (startup_info->have_repository) {
2052	struct strbuf err = STRBUF_INIT;
2053
2054	if (apply_repository_format(repo, &repo_fmt,
2055	APPLY_REPOSITORY_FORMAT_HONOR_ENV, &err) < 0)
2056	die("%s", err.buf);
2057
2058	clear_repository_format(&repo_fmt);
2059	strbuf_release(&err);
2060	}
2061	}
2062	/*
2063	* Since precompose_string_if_needed() needs to look at
2064	* the core.precomposeunicode configuration, this
2065	* has to happen after the above block that finds
2066	* out where the repository is, i.e. a preparation
2067	* for calling repo_config_get_bool().
2068	*/
2069	if (prefix) {
2070	prefix = precompose_string_if_needed(prefix);
2071	startup_info->prefix = prefix;
2072	setenv(GIT_PREFIX_ENVIRONMENT, prefix, 1);
2073	} else {
2074	startup_info->prefix = NULL;
2075	setenv(GIT_PREFIX_ENVIRONMENT, "", 1);
2076	}
2077
2078	/*
2079	* The env variable should override the repository config
2080	* for 'extensions.refStorage'.
2081	*/
2082	ref_backend_uri = getenv(GIT_REFERENCE_BACKEND_ENVIRONMENT);
2083	if (ref_backend_uri) {
2084	char backend, payload;
2085	enum ref_storage_format format;
2086
2087	parse_reference_uri(ref_backend_uri, &backend, &payload);
2088	format = ref_storage_format_by_name(backend);
2089	if (format == REF_STORAGE_FORMAT_UNKNOWN)
2090	die(_("unknown ref storage format: '%s'"), backend);
2091	repo_set_ref_storage_format(repo, format, payload);
2092
2093	free(backend);
2094	free(payload);
2095	}
2096
2097	setup_original_cwd(repo);
2098
2099	strbuf_release(&dir);
2100	strbuf_release(&gitdir);
2101	strbuf_release(&report);
2102	clear_repository_format(&repo_fmt);
2103
2104	return prefix;
2105	}
2106
2107	int git_config_perm(const char var, const char value)
2108	{
2109	int i;
2110	char *endptr;
2111
2112	if (!value)
2113	return PERM_GROUP;
2114
2115	if (!strcmp(value, "umask"))
2116	return PERM_UMASK;
2117	if (!strcmp(value, "group"))
2118	return PERM_GROUP;
2119	if (!strcmp(value, "all") \|\|
2120	!strcmp(value, "world") \|\|
2121	!strcmp(value, "everybody"))
2122	return PERM_EVERYBODY;
2123
2124	/* Parse octal numbers */
2125	i = strtol(value, &endptr, 8);
2126
2127	/* If not an octal number, maybe true/false? */
2128	if (*endptr != 0)
2129	return git_config_bool(var, value) ? PERM_GROUP : PERM_UMASK;
2130
2131	/*
2132	* Treat values 0, 1 and 2 as compatibility cases, otherwise it is
2133	* a chmod value to restrict to.
2134	*/
2135	switch (i) {
2136	case PERM_UMASK: /* 0 */
2137	return PERM_UMASK;
2138	case OLD_PERM_GROUP: /* 1 */
2139	return PERM_GROUP;
2140	case OLD_PERM_EVERYBODY: /* 2 */
2141	return PERM_EVERYBODY;
2142	}
2143
2144	/* A filemode value was given: 0xxx */
2145
2146	if ((i & 0600) != 0600)
2147	die(_("problem with core.sharedRepository filemode value "
2148	"(0%.3o).\nThe owner of files must always have "
2149	"read and write permissions."), i);
2150
2151	/*
2152	* Mask filemode value. Others can not get write permission.
2153	* x flags for directories are handled separately.
2154	*/
2155	return -(i & 0666);
2156	}
2157
2158	/*
2159	* Returns the "prefix", a path to the current working directory
2160	* relative to the work tree root, or NULL, if the current working
2161	* directory is not a strict subdirectory of the work tree root. The
2162	* prefix always ends with a '/' character.
2163	*/
2164	const char setup_git_directory(struct repository repo)
2165	{
2166	return setup_git_directory_gently(repo, NULL);
2167	}
2168
2169	const char resolve_gitdir_gently(const char suspect, int *return_error_code)
2170	{
2171	if (is_git_directory(suspect))
2172	return suspect;
2173	return read_gitfile_gently(suspect, return_error_code);
2174	}
2175
2176	/* if any standard file descriptor is missing open it to /dev/null */
2177	void sanitize_stdfds(void)
2178	{
2179	int fd = xopen("/dev/null", O_RDWR);
2180	while (fd < 2)
2181	fd = xdup(fd);
2182	if (fd > 2)
2183	close(fd);
2184	}
2185
2186	int daemonize(void)
2187	{
2188	#ifdef NO_POSIX_GOODIES
2189	errno = ENOSYS;
2190	return -1;
2191	#else
2192	pid_t parent_pid = getpid();
2193	pid_t child_pid = fork();
2194
2195	switch (child_pid) {
2196	case 0:
2197	/*
2198	* We're in the child process, so we take ownership of
2199	* all tempfiles.
2200	*/
2201	reassign_tempfile_ownership(parent_pid, getpid());
2202	break;
2203	case -1:
2204	die_errno(_("fork failed"));
2205	default:
2206	/*
2207	* We're in the parent process, so we drop ownership of
2208	* all tempfiles to prevent us from removing them upon
2209	* exit.
2210	*/
2211	reassign_tempfile_ownership(parent_pid, child_pid);
2212	exit(0);
2213	}
2214	if (setsid() == -1)
2215	die_errno(_("setsid failed"));
2216	close(0);
2217	close(1);
2218	close(2);
2219	sanitize_stdfds();
2220	return 0;
2221	#endif
2222	}
2223
2224	struct template_dir_cb_data {
2225	char *path;
2226	int initialized;
2227	};
2228
2229	static int template_dir_cb(const char key, const char value,
2230	const struct config_context ctx UNUSED, void d)
2231	{
2232	struct template_dir_cb_data *data = d;
2233
2234	if (strcmp(key, "init.templatedir"))
2235	return 0;
2236
2237	if (!value) {
2238	data->path = NULL;
2239	} else {
2240	char *path = NULL;
2241
2242	FREE_AND_NULL(data->path);
2243	if (!git_config_pathname(&path, key, value))
2244	data->path = path ? path : xstrdup(value);
2245	}
2246
2247	return 0;
2248	}
2249
2250	const char get_template_dir(const char option_template)
2251	{
2252	const char *template_dir = option_template;
2253
2254	if (!template_dir)
2255	template_dir = getenv(TEMPLATE_DIR_ENVIRONMENT);
2256	if (!template_dir) {
2257	static struct template_dir_cb_data data;
2258
2259	if (!data.initialized) {
2260	git_protected_config(template_dir_cb, &data);
2261	data.initialized = 1;
2262	}
2263	template_dir = data.path;
2264	}
2265	if (!template_dir) {
2266	static char *dir;
2267
2268	if (!dir)
2269	dir = system_path(DEFAULT_GIT_TEMPLATE_DIR);
2270	template_dir = dir;
2271	}
2272	return template_dir;
2273	}
2274
2275	#ifdef NO_TRUSTABLE_FILEMODE
2276	#define TEST_FILEMODE 0
2277	#else
2278	#define TEST_FILEMODE 1
2279	#endif
2280
2281	#define GIT_DEFAULT_HASH_ENVIRONMENT "GIT_DEFAULT_HASH"
2282
2283	static void copy_templates_1(struct repository *repo,
2284	struct strbuf *path,
2285	struct strbuf *template_path,
2286	DIR *dir)
2287	{
2288	size_t path_baselen = path->len;
2289	size_t template_baselen = template_path->len;
2290	struct dirent *de;
2291
2292	/* Note: if ".git/hooks" file exists in the repository being
2293	* re-initialized, /etc/core-git/templates/hooks/update would
2294	* cause "git init" to fail here. I think this is sane but
2295	* it means that the set of templates we ship by default, along
2296	* with the way the namespace under .git/ is organized, should
2297	* be really carefully chosen.
2298	*/
2299	safe_create_dir(repo, path->buf, 1);
2300	while ((de = readdir(dir)) != NULL) {
2301	struct stat st_git, st_template;
2302	int exists = 0;
2303
2304	strbuf_setlen(path, path_baselen);
2305	strbuf_setlen(template_path, template_baselen);
2306
2307	if (de->d_name[0] == '.')
2308	continue;
2309	strbuf_addstr(path, de->d_name);
2310	strbuf_addstr(template_path, de->d_name);
2311	if (lstat(path->buf, &st_git)) {
2312	if (errno != ENOENT)
2313	die_errno(_("cannot stat '%s'"), path->buf);
2314	}
2315	else
2316	exists = 1;
2317
2318	if (lstat(template_path->buf, &st_template))
2319	die_errno(_("cannot stat template '%s'"), template_path->buf);
2320
2321	if (S_ISDIR(st_template.st_mode)) {
2322	DIR *subdir = opendir(template_path->buf);
2323	if (!subdir)
2324	die_errno(_("cannot opendir '%s'"), template_path->buf);
2325	strbuf_addch(path, '/');
2326	strbuf_addch(template_path, '/');
2327	copy_templates_1(repo, path, template_path, subdir);
2328	closedir(subdir);
2329	}
2330	else if (exists)
2331	continue;
2332	else if (S_ISLNK(st_template.st_mode)) {
2333	struct strbuf lnk = STRBUF_INIT;
2334	if (strbuf_readlink(&lnk, template_path->buf,
2335	st_template.st_size) < 0)
2336	die_errno(_("cannot readlink '%s'"), template_path->buf);
2337	if (symlink(lnk.buf, path->buf))
2338	die_errno(_("cannot symlink '%s' '%s'"),
2339	lnk.buf, path->buf);
2340	strbuf_release(&lnk);
2341	}
2342	else if (S_ISREG(st_template.st_mode)) {
2343	if (copy_file(path->buf, template_path->buf, st_template.st_mode))
2344	die_errno(_("cannot copy '%s' to '%s'"),
2345	template_path->buf, path->buf);
2346	}
2347	else
2348	error(_("ignoring template %s"), template_path->buf);
2349	}
2350	}
2351
2352	static void copy_templates(struct repository repo, const char option_template)
2353	{
2354	const char *template_dir = get_template_dir(option_template);
2355	struct strbuf path = STRBUF_INIT;
2356	struct strbuf template_path = STRBUF_INIT;
2357	size_t template_len;
2358	struct repository_format template_format = REPOSITORY_FORMAT_INIT;
2359	struct strbuf err = STRBUF_INIT;
2360	DIR *dir;
2361	char *to_free = NULL;
2362
2363	if (!template_dir \|\| !*template_dir)
2364	return;
2365
2366	strbuf_addstr(&template_path, template_dir);
2367	strbuf_complete(&template_path, '/');
2368	template_len = template_path.len;
2369
2370	dir = opendir(template_path.buf);
2371	if (!dir) {
2372	warning(_("templates not found in %s"), template_dir);
2373	goto free_return;
2374	}
2375
2376	/* Make sure that template is from the correct vintage */
2377	strbuf_addstr(&template_path, "config");
2378	read_repository_format(&template_format, template_path.buf);
2379	strbuf_setlen(&template_path, template_len);
2380
2381	/*
2382	* No mention of version at all is OK, but anything else should be
2383	* verified.
2384	*/
2385	if (template_format.version >= 0 &&
2386	verify_repository_format(&template_format, &err) < 0) {
2387	warning(_("not copying templates from '%s': %s"),
2388	template_dir, err.buf);
2389	strbuf_release(&err);
2390	goto close_free_return;
2391	}
2392
2393	strbuf_addstr(&path, repo_get_common_dir(repo));
2394	strbuf_complete(&path, '/');
2395	copy_templates_1(repo, &path, &template_path, dir);
2396	close_free_return:
2397	closedir(dir);
2398	free_return:
2399	free(to_free);
2400	strbuf_release(&path);
2401	strbuf_release(&template_path);
2402	clear_repository_format(&template_format);
2403	}
2404
2405	/*
2406	* If the git_dir is not directly inside the working tree, then git will not
2407	* find it by default, and we need to set the worktree explicitly.
2408	*/
2409	static int needs_work_tree_config(const char git_dir, const char work_tree)
2410	{
2411	if (!strcmp(work_tree, "/") && !strcmp(git_dir, "/.git"))
2412	return 0;
2413	if (skip_prefix(git_dir, work_tree, &git_dir) &&
2414	!strcmp(git_dir, "/.git"))
2415	return 0;
2416	return 1;
2417	}
2418
2419	void initialize_repository_version(struct repository *repo,
2420	int hash_algo,
2421	enum ref_storage_format ref_storage_format,
2422	int reinit)
2423	{
2424	struct strbuf repo_version = STRBUF_INIT;
2425	int target_version = GIT_REPO_VERSION;
2426	int default_submodule_path_config = 0;
2427
2428	/*
2429	* Note that we initialize the repository version to 1 when the ref
2430	* storage format is unknown. This is on purpose so that we can add the
2431	* correct object format to the config during git-clone(1). The format
2432	* version will get adjusted by git-clone(1) once it has learned about
2433	* the remote repository's format.
2434	*/
2435	if (hash_algo != GIT_HASH_SHA1_LEGACY \|\|
2436	ref_storage_format != REF_STORAGE_FORMAT_FILES \|\|
2437	repo->ref_storage_payload)
2438	target_version = GIT_REPO_VERSION_READ;
2439
2440	if (hash_algo != GIT_HASH_SHA1_LEGACY && hash_algo != GIT_HASH_UNKNOWN)
2441	repo_config_set(repo, "extensions.objectformat",
2442	hash_algos[hash_algo].name);
2443	else if (reinit)
2444	repo_config_set_gently(repo, "extensions.objectformat", NULL);
2445
2446	if (repo->ref_storage_payload) {
2447	struct strbuf ref_uri = STRBUF_INIT;
2448
2449	strbuf_addf(&ref_uri, "%s://%s",
2450	ref_storage_format_to_name(ref_storage_format),
2451	repo->ref_storage_payload);
2452	repo_config_set(repo, "extensions.refstorage", ref_uri.buf);
2453	strbuf_release(&ref_uri);
2454	} else if (ref_storage_format != REF_STORAGE_FORMAT_FILES) {
2455	repo_config_set(repo, "extensions.refstorage",
2456	ref_storage_format_to_name(ref_storage_format));
2457	} else if (reinit) {
2458	repo_config_set_gently(repo, "extensions.refstorage", NULL);
2459	}
2460
2461	if (reinit) {
2462	struct strbuf config = STRBUF_INIT;
2463	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
2464
2465	repo_common_path_append(repo, &config, "config");
2466	read_repository_format(&repo_fmt, config.buf);
2467
2468	if (repo_fmt.v1_only_extensions.nr)
2469	target_version = GIT_REPO_VERSION_READ;
2470
2471	strbuf_release(&config);
2472	clear_repository_format(&repo_fmt);
2473	}
2474
2475	repo_config_get_bool(repo, "init.defaultSubmodulePathConfig",
2476	&default_submodule_path_config);
2477	if (default_submodule_path_config) {
2478	/* extensions.submodulepathconfig requires at least version 1 */
2479	if (target_version == 0)
2480	target_version = 1;
2481	repo_config_set(repo, "extensions.submodulepathconfig", "true");
2482	}
2483
2484	strbuf_addf(&repo_version, "%d", target_version);
2485	repo_config_set(repo, "core.repositoryformatversion", repo_version.buf);
2486
2487	strbuf_release(&repo_version);
2488	}
2489
2490	static int is_reinit(struct repository *repo)
2491	{
2492	struct strbuf buf = STRBUF_INIT;
2493	char junk[2];
2494	int ret;
2495
2496	repo_git_path_replace(repo, &buf, "HEAD");
2497	ret = !access(buf.buf, R_OK) \|\| readlink(buf.buf, junk, sizeof(junk) - 1) != -1;
2498	strbuf_release(&buf);
2499	return ret;
2500	}
2501
2502	void create_reference_database(struct repository *repo,
2503	const char *initial_branch, int quiet)
2504	{
2505	struct strbuf err = STRBUF_INIT;
2506	char *to_free = NULL;
2507	int reinit = is_reinit(repo);
2508
2509	if (ref_store_create_on_disk(get_main_ref_store(repo), 0, &err))
2510	die("failed to set up refs db: %s", err.buf);
2511
2512	/*
2513	* Point the HEAD symref to the initial branch with if HEAD does
2514	* not yet exist.
2515	*/
2516	if (!reinit) {
2517	char *ref;
2518
2519	if (!initial_branch)
2520	initial_branch = to_free =
2521	repo_default_branch_name(repo, quiet);
2522
2523	ref = xstrfmt("refs/heads/%s", initial_branch);
2524	if (check_refname_format(ref, 0) < 0)
2525	die(_("invalid initial branch name: '%s'"),
2526	initial_branch);
2527
2528	if (refs_update_symref(get_main_ref_store(repo), "HEAD", ref, NULL) < 0)
2529	exit(1);
2530	free(ref);
2531	}
2532
2533	if (reinit && initial_branch)
2534	warning(_("re-init: ignored --initial-branch=%s"),
2535	initial_branch);
2536
2537	strbuf_release(&err);
2538	free(to_free);
2539	}
2540
2541	static int create_default_files(struct repository *repo,
2542	const char *template_path,
2543	const char *original_git_dir,
2544	const struct repository_format *fmt,
2545	int init_shared_repository)
2546	{
2547	struct stat st1;
2548	struct strbuf path = STRBUF_INIT;
2549	int reinit;
2550	int filemode;
2551	const char *work_tree = repo_get_work_tree(repo);
2552
2553	/*
2554	* First copy the templates -- we might have the default
2555	* config file there, in which case we would want to read
2556	* from it after installing.
2557	*
2558	* Before reading that config, we also need to clear out any cached
2559	* values (since we've just potentially changed what's available on
2560	* disk).
2561	*/
2562	copy_templates(repo, template_path);
2563	repo_config_clear(repo);
2564	repo_settings_reset_shared_repository(repo);
2565	repo_config(repo, git_default_config, NULL);
2566
2567	reinit = is_reinit(repo);
2568
2569	/*
2570	* We must make sure command-line options continue to override any
2571	* values we might have just re-read from the config.
2572	*/
2573	if (init_shared_repository != -1)
2574	repo_settings_set_shared_repository(repo,
2575	init_shared_repository);
2576
2577	is_bare_repository_cfg = !work_tree;
2578
2579	/*
2580	* We would have created the above under user's umask -- under
2581	* shared-repository settings, we would need to fix them up.
2582	*/
2583	if (repo_settings_get_shared_repository(repo)) {
2584	adjust_shared_perm(repo, repo_get_git_dir(repo));
2585	}
2586
2587	initialize_repository_version(repo, fmt->hash_algo, fmt->ref_storage_format, reinit);
2588
2589	/* Check filemode trustability */
2590	repo_git_path_replace(repo, &path, "config");
2591	filemode = TEST_FILEMODE;
2592	if (TEST_FILEMODE && !lstat(path.buf, &st1)) {
2593	struct stat st2;
2594	filemode = (!chmod(path.buf, st1.st_mode ^ S_IXUSR) &&
2595	!lstat(path.buf, &st2) &&
2596	st1.st_mode != st2.st_mode &&
2597	!chmod(path.buf, st1.st_mode));
2598	if (filemode && !reinit && (st1.st_mode & S_IXUSR))
2599	filemode = 0;
2600	}
2601	repo_config_set(repo, "core.filemode", filemode ? "true" : "false");
2602
2603	if (is_bare_repository())
2604	repo_config_set(repo, "core.bare", "true");
2605	else {
2606	repo_config_set(repo, "core.bare", "false");
2607	/* allow template config file to override the default */
2608	if (repo_settings_get_log_all_ref_updates(repo) == LOG_REFS_UNSET)
2609	repo_config_set(repo, "core.logallrefupdates", "true");
2610	if (needs_work_tree_config(original_git_dir, work_tree))
2611	repo_config_set(repo, "core.worktree", work_tree);
2612	}
2613
2614	if (!reinit) {
2615	/* Check if symlink is supported in the work tree */
2616	repo_git_path_replace(repo, &path, "tXXXXXX");
2617	if (!close(xmkstemp(path.buf)) &&
2618	!unlink(path.buf) &&
2619	!symlink("testing", path.buf) &&
2620	!lstat(path.buf, &st1) &&
2621	S_ISLNK(st1.st_mode))
2622	unlink(path.buf); /* good */
2623	else
2624	repo_config_set(repo, "core.symlinks", "false");
2625
2626	/* Check if the filesystem is case-insensitive */
2627	repo_git_path_replace(repo, &path, "CoNfIg");
2628	if (!access(path.buf, F_OK))
2629	repo_config_set(repo, "core.ignorecase", "true");
2630	probe_utf8_pathname_composition();
2631	}
2632
2633	strbuf_release(&path);
2634	return reinit;
2635	}
2636
2637	static void create_object_directory(struct repository *repo)
2638	{
2639	struct strbuf path = STRBUF_INIT;
2640	size_t baselen;
2641
2642	strbuf_addstr(&path, repo_get_object_directory(repo));
2643	baselen = path.len;
2644
2645	safe_create_dir(repo, path.buf, 1);
2646
2647	strbuf_setlen(&path, baselen);
2648	strbuf_addstr(&path, "/pack");
2649	safe_create_dir(repo, path.buf, 1);
2650
2651	strbuf_setlen(&path, baselen);
2652	strbuf_addstr(&path, "/info");
2653	safe_create_dir(repo, path.buf, 1);
2654
2655	strbuf_release(&path);
2656	}
2657
2658	static void separate_git_dir(const char git_dir, const char git_link)
2659	{
2660	struct stat st;
2661
2662	if (!stat(git_link, &st)) {
2663	const char *src;
2664
2665	if (S_ISREG(st.st_mode))
2666	src = read_gitfile(git_link);
2667	else if (S_ISDIR(st.st_mode))
2668	src = git_link;
2669	else
2670	die(_("unable to handle file type %d"), (int)st.st_mode);
2671
2672	if (rename(src, git_dir))
2673	die_errno(_("unable to move %s to %s"), src, git_dir);
2674	repair_worktrees_after_gitdir_move(src);
2675	}
2676
2677	write_file(git_link, "gitdir: %s", git_dir);
2678	}
2679
2680	struct default_format_config {
2681	int hash;
2682	enum ref_storage_format ref_format;
2683	};
2684
2685	static int read_default_format_config(const char key, const char value,
2686	const struct config_context *ctx UNUSED,
2687	void *payload)
2688	{
2689	struct default_format_config *cfg = payload;
2690	char *str = NULL;
2691	int ret;
2692
2693	if (!strcmp(key, "init.defaultobjectformat")) {
2694	ret = git_config_string(&str, key, value);
2695	if (ret)
2696	goto out;
2697	cfg->hash = hash_algo_by_name(str);
2698	if (cfg->hash == GIT_HASH_UNKNOWN)
2699	warning(_("unknown hash algorithm '%s'"), str);
2700	goto out;
2701	}
2702
2703	if (!strcmp(key, "init.defaultrefformat")) {
2704	ret = git_config_string(&str, key, value);
2705	if (ret)
2706	goto out;
2707	cfg->ref_format = ref_storage_format_by_name(str);
2708	if (cfg->ref_format == REF_STORAGE_FORMAT_UNKNOWN)
2709	warning(_("unknown ref storage format '%s'"), str);
2710	goto out;
2711	}
2712
2713	/*
2714	* Enable the reftable format when "features.experimental" is enabled.
2715	* "init.defaultRefFormat" takes precedence over this setting.
2716	*/
2717	if (!strcmp(key, "feature.experimental") &&
2718	cfg->ref_format == REF_STORAGE_FORMAT_UNKNOWN &&
2719	git_config_bool(key, value)) {
2720	cfg->ref_format = REF_STORAGE_FORMAT_REFTABLE;
2721	ret = 0;
2722	goto out;
2723	}
2724
2725	ret = 0;
2726	out:
2727	free(str);
2728	return ret;
2729	}
2730
2731	static void repository_format_configure(struct repository *repo,
2732	struct repository_format *repo_fmt,
2733	int hash, enum ref_storage_format ref_format)
2734	{
2735	struct default_format_config cfg = {
2736	.hash = GIT_HASH_UNKNOWN,
2737	.ref_format = REF_STORAGE_FORMAT_UNKNOWN,
2738	};
2739	struct config_options opts = {
2740	.respect_includes = 1,
2741	.ignore_repo = 1,
2742	.ignore_worktree = 1,
2743	};
2744	const char *ref_backend_uri;
2745	const char *env;
2746
2747	config_with_options(read_default_format_config, &cfg, NULL, NULL, &opts);
2748
2749	/*
2750	* If we already have an initialized repo, don't allow the user to
2751	* specify a different algorithm, as that could cause corruption.
2752	* Otherwise, if the user has specified one on the command line, use it.
2753	*/
2754	env = getenv(GIT_DEFAULT_HASH_ENVIRONMENT);
2755	if (repo_fmt->version >= 0 && hash != GIT_HASH_UNKNOWN && hash != repo_fmt->hash_algo)
2756	die(_("attempt to reinitialize repository with different hash"));
2757	else if (hash != GIT_HASH_UNKNOWN)
2758	repo_fmt->hash_algo = hash;
2759	else if (env) {
2760	int env_algo = hash_algo_by_name(env);
2761	if (env_algo == GIT_HASH_UNKNOWN)
2762	die(_("unknown hash algorithm '%s'"), env);
2763	if (repo_fmt->version < 0 \|\|
2764	repo_fmt->hash_algo == GIT_HASH_UNKNOWN)
2765	repo_fmt->hash_algo = env_algo;
2766	} else if (cfg.hash != GIT_HASH_UNKNOWN) {
2767	repo_fmt->hash_algo = cfg.hash;
2768	}
2769	repo_set_hash_algo(repo, repo_fmt->hash_algo);
2770
2771	env = getenv("GIT_DEFAULT_REF_FORMAT");
2772	if (repo_fmt->version >= 0 &&
2773	ref_format != REF_STORAGE_FORMAT_UNKNOWN &&
2774	ref_format != repo_fmt->ref_storage_format) {
2775	die(_("attempt to reinitialize repository with different reference storage format"));
2776	} else if (ref_format != REF_STORAGE_FORMAT_UNKNOWN) {
2777	repo_fmt->ref_storage_format = ref_format;
2778	} else if (env) {
2779	ref_format = ref_storage_format_by_name(env);
2780	if (ref_format == REF_STORAGE_FORMAT_UNKNOWN)
2781	die(_("unknown ref storage format '%s'"), env);
2782	if (repo_fmt->version < 0 \|\|
2783	repo_fmt->ref_storage_format == REF_STORAGE_FORMAT_UNKNOWN)
2784	repo_fmt->ref_storage_format = ref_format;
2785	} else if (cfg.ref_format != REF_STORAGE_FORMAT_UNKNOWN) {
2786	repo_fmt->ref_storage_format = cfg.ref_format;
2787	} else {
2788	repo_fmt->ref_storage_format = REF_STORAGE_FORMAT_DEFAULT;
2789	}
2790
2791
2792	ref_backend_uri = getenv(GIT_REFERENCE_BACKEND_ENVIRONMENT);
2793	if (ref_backend_uri) {
2794	char backend, payload;
2795	enum ref_storage_format format;
2796
2797	parse_reference_uri(ref_backend_uri, &backend, &payload);
2798	format = ref_storage_format_by_name(backend);
2799	if (format == REF_STORAGE_FORMAT_UNKNOWN)
2800	die(_("unknown ref storage format: '%s'"), backend);
2801
2802	repo_fmt->ref_storage_format = format;
2803	repo_fmt->ref_storage_payload = payload;
2804
2805	free(backend);
2806	}
2807
2808	repo_set_ref_storage_format(repo, repo_fmt->ref_storage_format,
2809	repo_fmt->ref_storage_payload);
2810	}
2811
2812	int init_db(struct repository *repo,
2813	const char git_dir, const char real_git_dir,
2814	const char *template_dir, int hash,
2815	enum ref_storage_format ref_storage_format,
2816	const char *initial_branch,
2817	int init_shared_repository, unsigned int flags)
2818	{
2819	int reinit;
2820	int exist_ok = flags & INIT_DB_EXIST_OK;
2821	char *original_git_dir = real_pathdup(git_dir, 1);
2822	struct repository_format repo_fmt = REPOSITORY_FORMAT_INIT;
2823
2824	if (real_git_dir) {
2825	struct stat st;
2826
2827	if (!exist_ok && !stat(git_dir, &st))
2828	die(_("%s already exists"), git_dir);
2829
2830	if (!exist_ok && !stat(real_git_dir, &st))
2831	die(_("%s already exists"), real_git_dir);
2832
2833	set_git_dir(repo, real_git_dir, 1);
2834	git_dir = repo_get_git_dir(repo);
2835	separate_git_dir(git_dir, original_git_dir);
2836	}
2837	else {
2838	set_git_dir(repo, git_dir, 1);
2839	git_dir = repo_get_git_dir(repo);
2840	}
2841	startup_info->have_repository = 1;
2842
2843	/*
2844	* Check to see if the repository version is right.
2845	* Note that a newly created repository does not have
2846	* config file, so this will not fail. What we are catching
2847	* is an attempt to reinitialize new repository with an old tool.
2848	*/
2849	check_and_apply_repository_format(repo, &repo_fmt,
2850	APPLY_REPOSITORY_FORMAT_HONOR_ENV);
2851
2852	repository_format_configure(repo, &repo_fmt, hash, ref_storage_format);
2853
2854	/*
2855	* Ensure `core.hidedotfiles` is processed. This must happen after we
2856	* have set up the repository format such that we can evaluate
2857	* includeIf conditions correctly in the case of re-initialization.
2858	*/
2859	repo_config(repo, git_default_core_config, NULL);
2860
2861	safe_create_dir(repo, git_dir, 0);
2862
2863	reinit = create_default_files(repo, template_dir, original_git_dir,
2864	&repo_fmt, init_shared_repository);
2865
2866	if (!(flags & INIT_DB_SKIP_REFDB))
2867	create_reference_database(repo, initial_branch, flags & INIT_DB_QUIET);
2868	create_object_directory(repo);
2869
2870	if (repo_settings_get_shared_repository(repo)) {
2871	char buf[10];
2872	/* We do not spell "group" and such, so that
2873	* the configuration can be read by older version
2874	* of git. Note, we use octal numbers for new share modes,
2875	* and compatibility values for PERM_GROUP and
2876	* PERM_EVERYBODY.
2877	*/
2878	if (repo_settings_get_shared_repository(repo) < 0)
2879	/* force to the mode value */
2880	xsnprintf(buf, sizeof(buf), "0%o", -repo_settings_get_shared_repository(repo));
2881	else if (repo_settings_get_shared_repository(repo) == PERM_GROUP)
2882	xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_GROUP);
2883	else if (repo_settings_get_shared_repository(repo) == PERM_EVERYBODY)
2884	xsnprintf(buf, sizeof(buf), "%d", OLD_PERM_EVERYBODY);
2885	else
2886	BUG("invalid value for shared_repository");
2887	repo_config_set(repo, "core.sharedrepository", buf);
2888	repo_config_set(repo, "receive.denyNonFastforwards", "true");
2889	}
2890
2891	if (!(flags & INIT_DB_QUIET)) {
2892	int len = strlen(git_dir);
2893
2894	if (reinit)
2895	printf(repo_settings_get_shared_repository(repo)
2896	? _("Reinitialized existing shared Git repository in %s%s\n")
2897	: _("Reinitialized existing Git repository in %s%s\n"),
2898	git_dir, len && git_dir[len-1] != '/' ? "/" : "");
2899	else
2900	printf(repo_settings_get_shared_repository(repo)
2901	? _("Initialized empty shared Git repository in %s%s\n")
2902	: _("Initialized empty Git repository in %s%s\n"),
2903	git_dir, len && git_dir[len-1] != '/' ? "/" : "");
2904	}
2905
2906	clear_repository_format(&repo_fmt);
2907	free(original_git_dir);
2908	return 0;
2909	}