range-diff doc: add a section about output stability
[git] / repository.c
1 #include "cache.h"
2 #include "repository.h"
3 #include "object-store.h"
4 #include "config.h"
5 #include "object.h"
6 #include "submodule-config.h"
7
8 /* The main repository */
9 static struct repository the_repo;
10 struct repository *the_repository;
11
12 void initialize_the_repository(void)
13 {
14         the_repository = &the_repo;
15
16         the_repo.index = &the_index;
17         the_repo.objects = raw_object_store_new();
18         the_repo.parsed_objects = parsed_object_pool_new();
19
20         repo_set_hash_algo(&the_repo, GIT_HASH_SHA1);
21 }
22
23 static void expand_base_dir(char **out, const char *in,
24                             const char *base_dir, const char *def_in)
25 {
26         free(*out);
27         if (in)
28                 *out = xstrdup(in);
29         else
30                 *out = xstrfmt("%s/%s", base_dir, def_in);
31 }
32
33 static void repo_set_commondir(struct repository *repo,
34                                const char *commondir)
35 {
36         struct strbuf sb = STRBUF_INIT;
37
38         free(repo->commondir);
39
40         if (commondir) {
41                 repo->different_commondir = 1;
42                 repo->commondir = xstrdup(commondir);
43                 return;
44         }
45
46         repo->different_commondir = get_common_dir_noenv(&sb, repo->gitdir);
47         repo->commondir = strbuf_detach(&sb, NULL);
48 }
49
50 void repo_set_gitdir(struct repository *repo,
51                      const char *root,
52                      const struct set_gitdir_args *o)
53 {
54         const char *gitfile = read_gitfile(root);
55         /*
56          * repo->gitdir is saved because the caller could pass "root"
57          * that also points to repo->gitdir. We want to keep it alive
58          * until after xstrdup(root). Then we can free it.
59          */
60         char *old_gitdir = repo->gitdir;
61
62         repo->gitdir = xstrdup(gitfile ? gitfile : root);
63         free(old_gitdir);
64
65         repo_set_commondir(repo, o->commondir);
66         expand_base_dir(&repo->objects->objectdir, o->object_dir,
67                         repo->commondir, "objects");
68         free(repo->objects->alternate_db);
69         repo->objects->alternate_db = xstrdup_or_null(o->alternate_db);
70         expand_base_dir(&repo->graft_file, o->graft_file,
71                         repo->commondir, "info/grafts");
72         expand_base_dir(&repo->index_file, o->index_file,
73                         repo->gitdir, "index");
74 }
75
76 void repo_set_hash_algo(struct repository *repo, int hash_algo)
77 {
78         repo->hash_algo = &hash_algos[hash_algo];
79 }
80
81 /*
82  * Attempt to resolve and set the provided 'gitdir' for repository 'repo'.
83  * Return 0 upon success and a non-zero value upon failure.
84  */
85 static int repo_init_gitdir(struct repository *repo, const char *gitdir)
86 {
87         int ret = 0;
88         int error = 0;
89         char *abspath = NULL;
90         const char *resolved_gitdir;
91         struct set_gitdir_args args = { NULL };
92
93         abspath = real_pathdup(gitdir, 0);
94         if (!abspath) {
95                 ret = -1;
96                 goto out;
97         }
98
99         /* 'gitdir' must reference the gitdir directly */
100         resolved_gitdir = resolve_gitdir_gently(abspath, &error);
101         if (!resolved_gitdir) {
102                 ret = -1;
103                 goto out;
104         }
105
106         repo_set_gitdir(repo, resolved_gitdir, &args);
107
108 out:
109         free(abspath);
110         return ret;
111 }
112
113 void repo_set_worktree(struct repository *repo, const char *path)
114 {
115         repo->worktree = real_pathdup(path, 1);
116 }
117
118 static int read_and_verify_repository_format(struct repository_format *format,
119                                              const char *commondir)
120 {
121         int ret = 0;
122         struct strbuf sb = STRBUF_INIT;
123
124         strbuf_addf(&sb, "%s/config", commondir);
125         read_repository_format(format, sb.buf);
126         strbuf_reset(&sb);
127
128         if (verify_repository_format(format, &sb) < 0) {
129                 warning("%s", sb.buf);
130                 ret = -1;
131         }
132
133         strbuf_release(&sb);
134         return ret;
135 }
136
137 /*
138  * Initialize 'repo' based on the provided 'gitdir'.
139  * Return 0 upon success and a non-zero value upon failure.
140  */
141 int repo_init(struct repository *repo,
142               const char *gitdir,
143               const char *worktree)
144 {
145         struct repository_format format;
146         memset(repo, 0, sizeof(*repo));
147
148         repo->objects = raw_object_store_new();
149         repo->parsed_objects = parsed_object_pool_new();
150
151         if (repo_init_gitdir(repo, gitdir))
152                 goto error;
153
154         if (read_and_verify_repository_format(&format, repo->commondir))
155                 goto error;
156
157         repo_set_hash_algo(repo, format.hash_algo);
158
159         if (worktree)
160                 repo_set_worktree(repo, worktree);
161
162         return 0;
163
164 error:
165         repo_clear(repo);
166         return -1;
167 }
168
169 /*
170  * Initialize 'submodule' as the submodule given by 'path' in parent repository
171  * 'superproject'.
172  * Return 0 upon success and a non-zero value upon failure.
173  */
174 int repo_submodule_init(struct repository *submodule,
175                         struct repository *superproject,
176                         const char *path)
177 {
178         const struct submodule *sub;
179         struct strbuf gitdir = STRBUF_INIT;
180         struct strbuf worktree = STRBUF_INIT;
181         int ret = 0;
182
183         sub = submodule_from_path(superproject, &null_oid, path);
184         if (!sub) {
185                 ret = -1;
186                 goto out;
187         }
188
189         strbuf_repo_worktree_path(&gitdir, superproject, "%s/.git", path);
190         strbuf_repo_worktree_path(&worktree, superproject, "%s", path);
191
192         if (repo_init(submodule, gitdir.buf, worktree.buf)) {
193                 /*
194                  * If initilization fails then it may be due to the submodule
195                  * not being populated in the superproject's worktree.  Instead
196                  * we can try to initilize the submodule by finding it's gitdir
197                  * in the superproject's 'modules' directory.  In this case the
198                  * submodule would not have a worktree.
199                  */
200                 strbuf_reset(&gitdir);
201                 strbuf_repo_git_path(&gitdir, superproject,
202                                      "modules/%s", sub->name);
203
204                 if (repo_init(submodule, gitdir.buf, NULL)) {
205                         ret = -1;
206                         goto out;
207                 }
208         }
209
210         submodule->submodule_prefix = xstrfmt("%s%s/",
211                                               superproject->submodule_prefix ?
212                                               superproject->submodule_prefix :
213                                               "", path);
214
215 out:
216         strbuf_release(&gitdir);
217         strbuf_release(&worktree);
218         return ret;
219 }
220
221 void repo_clear(struct repository *repo)
222 {
223         FREE_AND_NULL(repo->gitdir);
224         FREE_AND_NULL(repo->commondir);
225         FREE_AND_NULL(repo->graft_file);
226         FREE_AND_NULL(repo->index_file);
227         FREE_AND_NULL(repo->worktree);
228         FREE_AND_NULL(repo->submodule_prefix);
229
230         raw_object_store_clear(repo->objects);
231         FREE_AND_NULL(repo->objects);
232
233         parsed_object_pool_clear(repo->parsed_objects);
234         FREE_AND_NULL(repo->parsed_objects);
235
236         if (repo->config) {
237                 git_configset_clear(repo->config);
238                 FREE_AND_NULL(repo->config);
239         }
240
241         if (repo->submodule_cache) {
242                 submodule_cache_free(repo->submodule_cache);
243                 repo->submodule_cache = NULL;
244         }
245
246         if (repo->index) {
247                 discard_index(repo->index);
248                 if (repo->index != &the_index)
249                         FREE_AND_NULL(repo->index);
250         }
251 }
252
253 int repo_read_index(struct repository *repo)
254 {
255         if (!repo->index)
256                 repo->index = xcalloc(1, sizeof(*repo->index));
257
258         return read_index_from(repo->index, repo->index_file, repo->gitdir);
259 }