worktree.c: add is_main_worktree()
[git] / worktree.c
1 #include "cache.h"
2 #include "refs.h"
3 #include "strbuf.h"
4 #include "worktree.h"
5 #include "dir.h"
6 #include "wt-status.h"
7
8 void free_worktrees(struct worktree **worktrees)
9 {
10         int i = 0;
11
12         for (i = 0; worktrees[i]; i++) {
13                 free(worktrees[i]->path);
14                 free(worktrees[i]->id);
15                 free(worktrees[i]->head_ref);
16                 free(worktrees[i]);
17         }
18         free (worktrees);
19 }
20
21 /*
22  * read 'path_to_ref' into 'ref'.  Also if is_detached is not NULL,
23  * set is_detached to 1 (0) if the ref is detatched (is not detached).
24  *
25  * $GIT_COMMON_DIR/$symref (e.g. HEAD) is practically outside $GIT_DIR so
26  * for linked worktrees, `resolve_ref_unsafe()` won't work (it uses
27  * git_path). Parse the ref ourselves.
28  *
29  * return -1 if the ref is not a proper ref, 0 otherwise (success)
30  */
31 static int parse_ref(char *path_to_ref, struct strbuf *ref, int *is_detached)
32 {
33         if (is_detached)
34                 *is_detached = 0;
35         if (!strbuf_readlink(ref, path_to_ref, 0)) {
36                 /* HEAD is symbolic link */
37                 if (!starts_with(ref->buf, "refs/") ||
38                                 check_refname_format(ref->buf, 0))
39                         return -1;
40         } else if (strbuf_read_file(ref, path_to_ref, 0) >= 0) {
41                 /* textual symref or detached */
42                 if (!starts_with(ref->buf, "ref:")) {
43                         if (is_detached)
44                                 *is_detached = 1;
45                 } else {
46                         strbuf_remove(ref, 0, strlen("ref:"));
47                         strbuf_trim(ref);
48                         if (check_refname_format(ref->buf, 0))
49                                 return -1;
50                 }
51         } else
52                 return -1;
53         return 0;
54 }
55
56 /**
57  * Add the head_sha1 and head_ref (if not detached) to the given worktree
58  */
59 static void add_head_info(struct strbuf *head_ref, struct worktree *worktree)
60 {
61         if (head_ref->len) {
62                 if (worktree->is_detached) {
63                         get_sha1_hex(head_ref->buf, worktree->head_sha1);
64                 } else {
65                         resolve_ref_unsafe(head_ref->buf, 0, worktree->head_sha1, NULL);
66                         worktree->head_ref = strbuf_detach(head_ref, NULL);
67                 }
68         }
69 }
70
71 /**
72  * get the main worktree
73  */
74 static struct worktree *get_main_worktree(void)
75 {
76         struct worktree *worktree = NULL;
77         struct strbuf path = STRBUF_INIT;
78         struct strbuf worktree_path = STRBUF_INIT;
79         struct strbuf head_ref = STRBUF_INIT;
80         int is_bare = 0;
81         int is_detached = 0;
82
83         strbuf_addstr(&worktree_path, absolute_path(get_git_common_dir()));
84         is_bare = !strbuf_strip_suffix(&worktree_path, "/.git");
85         if (is_bare)
86                 strbuf_strip_suffix(&worktree_path, "/.");
87
88         strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
89
90         if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
91                 goto done;
92
93         worktree = xmalloc(sizeof(struct worktree));
94         worktree->path = strbuf_detach(&worktree_path, NULL);
95         worktree->id = NULL;
96         worktree->is_bare = is_bare;
97         worktree->head_ref = NULL;
98         worktree->is_detached = is_detached;
99         worktree->is_current = 0;
100         add_head_info(&head_ref, worktree);
101
102 done:
103         strbuf_release(&path);
104         strbuf_release(&worktree_path);
105         strbuf_release(&head_ref);
106         return worktree;
107 }
108
109 static struct worktree *get_linked_worktree(const char *id)
110 {
111         struct worktree *worktree = NULL;
112         struct strbuf path = STRBUF_INIT;
113         struct strbuf worktree_path = STRBUF_INIT;
114         struct strbuf head_ref = STRBUF_INIT;
115         int is_detached = 0;
116
117         if (!id)
118                 die("Missing linked worktree name");
119
120         strbuf_git_common_path(&path, "worktrees/%s/gitdir", id);
121         if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
122                 /* invalid gitdir file */
123                 goto done;
124
125         strbuf_rtrim(&worktree_path);
126         if (!strbuf_strip_suffix(&worktree_path, "/.git")) {
127                 strbuf_reset(&worktree_path);
128                 strbuf_addstr(&worktree_path, absolute_path("."));
129                 strbuf_strip_suffix(&worktree_path, "/.");
130         }
131
132         strbuf_reset(&path);
133         strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
134
135         if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
136                 goto done;
137
138         worktree = xmalloc(sizeof(struct worktree));
139         worktree->path = strbuf_detach(&worktree_path, NULL);
140         worktree->id = xstrdup(id);
141         worktree->is_bare = 0;
142         worktree->head_ref = NULL;
143         worktree->is_detached = is_detached;
144         worktree->is_current = 0;
145         add_head_info(&head_ref, worktree);
146
147 done:
148         strbuf_release(&path);
149         strbuf_release(&worktree_path);
150         strbuf_release(&head_ref);
151         return worktree;
152 }
153
154 static void mark_current_worktree(struct worktree **worktrees)
155 {
156         char *git_dir = xstrdup(absolute_path(get_git_dir()));
157         int i;
158
159         for (i = 0; worktrees[i]; i++) {
160                 struct worktree *wt = worktrees[i];
161                 const char *wt_git_dir = get_worktree_git_dir(wt);
162
163                 if (!fspathcmp(git_dir, absolute_path(wt_git_dir))) {
164                         wt->is_current = 1;
165                         break;
166                 }
167         }
168         free(git_dir);
169 }
170
171 struct worktree **get_worktrees(void)
172 {
173         struct worktree **list = NULL;
174         struct strbuf path = STRBUF_INIT;
175         DIR *dir;
176         struct dirent *d;
177         int counter = 0, alloc = 2;
178
179         list = xmalloc(alloc * sizeof(struct worktree *));
180
181         if ((list[counter] = get_main_worktree()))
182                 counter++;
183
184         strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
185         dir = opendir(path.buf);
186         strbuf_release(&path);
187         if (dir) {
188                 while ((d = readdir(dir)) != NULL) {
189                         struct worktree *linked = NULL;
190                         if (is_dot_or_dotdot(d->d_name))
191                                 continue;
192
193                         if ((linked = get_linked_worktree(d->d_name))) {
194                                 ALLOC_GROW(list, counter + 1, alloc);
195                                 list[counter++] = linked;
196                         }
197                 }
198                 closedir(dir);
199         }
200         ALLOC_GROW(list, counter + 1, alloc);
201         list[counter] = NULL;
202
203         mark_current_worktree(list);
204         return list;
205 }
206
207 const char *get_worktree_git_dir(const struct worktree *wt)
208 {
209         if (!wt)
210                 return get_git_dir();
211         else if (!wt->id)
212                 return get_git_common_dir();
213         else
214                 return git_common_path("worktrees/%s", wt->id);
215 }
216
217 struct worktree *find_worktree(struct worktree **list,
218                                const char *prefix,
219                                const char *arg)
220 {
221         char *path;
222
223         arg = prefix_filename(prefix, strlen(prefix), arg);
224         path = xstrdup(real_path(arg));
225         for (; *list; list++)
226                 if (!fspathcmp(path, real_path((*list)->path)))
227                         break;
228         free(path);
229         return *list;
230 }
231
232 int is_main_worktree(const struct worktree *wt)
233 {
234         return !wt->id;
235 }
236
237 int is_worktree_being_rebased(const struct worktree *wt,
238                               const char *target)
239 {
240         struct wt_status_state state;
241         int found_rebase;
242
243         memset(&state, 0, sizeof(state));
244         found_rebase = wt_status_check_rebase(wt, &state) &&
245                 ((state.rebase_in_progress ||
246                   state.rebase_interactive_in_progress) &&
247                  state.branch &&
248                  starts_with(target, "refs/heads/") &&
249                  !strcmp(state.branch, target + strlen("refs/heads/")));
250         free(state.branch);
251         free(state.onto);
252         return found_rebase;
253 }
254
255 int is_worktree_being_bisected(const struct worktree *wt,
256                                const char *target)
257 {
258         struct wt_status_state state;
259         int found_rebase;
260
261         memset(&state, 0, sizeof(state));
262         found_rebase = wt_status_check_bisect(wt, &state) &&
263                 state.branch &&
264                 starts_with(target, "refs/heads/") &&
265                 !strcmp(state.branch, target + strlen("refs/heads/"));
266         free(state.branch);
267         return found_rebase;
268 }
269
270 /*
271  * note: this function should be able to detect shared symref even if
272  * HEAD is temporarily detached (e.g. in the middle of rebase or
273  * bisect). New commands that do similar things should update this
274  * function as well.
275  */
276 const struct worktree *find_shared_symref(const char *symref,
277                                           const char *target)
278 {
279         const struct worktree *existing = NULL;
280         struct strbuf path = STRBUF_INIT;
281         struct strbuf sb = STRBUF_INIT;
282         static struct worktree **worktrees;
283         int i = 0;
284
285         if (worktrees)
286                 free_worktrees(worktrees);
287         worktrees = get_worktrees();
288
289         for (i = 0; worktrees[i]; i++) {
290                 struct worktree *wt = worktrees[i];
291
292                 if (wt->is_detached && !strcmp(symref, "HEAD")) {
293                         if (is_worktree_being_rebased(wt, target)) {
294                                 existing = wt;
295                                 break;
296                         }
297                         if (is_worktree_being_bisected(wt, target)) {
298                                 existing = wt;
299                                 break;
300                         }
301                 }
302
303                 strbuf_reset(&path);
304                 strbuf_reset(&sb);
305                 strbuf_addf(&path, "%s/%s",
306                             get_worktree_git_dir(wt),
307                             symref);
308
309                 if (parse_ref(path.buf, &sb, NULL)) {
310                         continue;
311                 }
312
313                 if (!strcmp(sb.buf, target)) {
314                         existing = wt;
315                         break;
316                 }
317         }
318
319         strbuf_release(&path);
320         strbuf_release(&sb);
321
322         return existing;
323 }