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]->lock_reason);
  17                 free(worktrees[i]);
  18         }
  19         free (worktrees);
  20 }
  21
  22 /*
  23  * read 'path_to_ref' into 'ref'.  Also if is_detached is not NULL,
  24  * set is_detached to 1 (0) if the ref is detached (is not detached).
  25  *
  26  * $GIT_COMMON_DIR/$symref (e.g. HEAD) is practically outside $GIT_DIR so
  27  * for linked worktrees, `resolve_ref_unsafe()` won't work (it uses
  28  * git_path). Parse the ref ourselves.
  29  *
  30  * return -1 if the ref is not a proper ref, 0 otherwise (success)
  31  */
  32 static int parse_ref(char *path_to_ref, struct strbuf *ref, int *is_detached)
  33 {
  34         if (is_detached)
  35                 *is_detached = 0;
  36         if (!strbuf_readlink(ref, path_to_ref, 0)) {
  37                 /* HEAD is symbolic link */
  38                 if (!starts_with(ref->buf, "refs/") ||
  39                                 check_refname_format(ref->buf, 0))
  40                         return -1;
  41         } else if (strbuf_read_file(ref, path_to_ref, 0) >= 0) {
  42                 /* textual symref or detached */
  43                 if (!starts_with(ref->buf, "ref:")) {
  44                         if (is_detached)
  45                                 *is_detached = 1;
  46                 } else {
  47                         strbuf_remove(ref, 0, strlen("ref:"));
  48                         strbuf_trim(ref);
  49                         if (check_refname_format(ref->buf, 0))
  50                                 return -1;
  51                 }
  52         } else
  53                 return -1;
  54         return 0;
  55 }
  56
  57 /**
  58  * Add the head_sha1 and head_ref (if not detached) to the given worktree
  59  */
  60 static void add_head_info(struct strbuf *head_ref, struct worktree *worktree)
  61 {
  62         if (head_ref->len) {
  63                 if (worktree->is_detached) {
  64                         get_sha1_hex(head_ref->buf, worktree->head_sha1);
  65                 } else {
  66                         resolve_ref_unsafe(head_ref->buf, 0, worktree->head_sha1, NULL);
  67                         worktree->head_ref = strbuf_detach(head_ref, NULL);
  68                 }
  69         }
  70 }
  71
  72 /**
  73  * get the main worktree
  74  */
  75 static struct worktree *get_main_worktree(void)
  76 {
  77         struct worktree *worktree = NULL;
  78         struct strbuf path = STRBUF_INIT;
  79         struct strbuf worktree_path = STRBUF_INIT;
  80         struct strbuf head_ref = STRBUF_INIT;
  81         int is_bare = 0;
  82         int is_detached = 0;
  83
  84         strbuf_add_absolute_path(&worktree_path, get_git_common_dir());
  85         is_bare = !strbuf_strip_suffix(&worktree_path, "/.git");
  86         if (is_bare)
  87                 strbuf_strip_suffix(&worktree_path, "/.");
  88
  89         strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
  90
  91         worktree = xcalloc(1, sizeof(*worktree));
  92         worktree->path = strbuf_detach(&worktree_path, NULL);
  93         worktree->is_bare = is_bare;
  94         worktree->is_detached = is_detached;
  95         if (!parse_ref(path.buf, &head_ref, &is_detached))
  96                 add_head_info(&head_ref, worktree);
  97
  98         strbuf_release(&path);
  99         strbuf_release(&worktree_path);
 100         strbuf_release(&head_ref);
 101         return worktree;
 102 }
 103
 104 static struct worktree *get_linked_worktree(const char *id)
 105 {
 106         struct worktree *worktree = NULL;
 107         struct strbuf path = STRBUF_INIT;
 108         struct strbuf worktree_path = STRBUF_INIT;
 109         struct strbuf head_ref = STRBUF_INIT;
 110         int is_detached = 0;
 111
 112         if (!id)
 113                 die("Missing linked worktree name");
 114
 115         strbuf_git_common_path(&path, "worktrees/%s/gitdir", id);
 116         if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
 117                 /* invalid gitdir file */
 118                 goto done;
 119
 120         strbuf_rtrim(&worktree_path);
 121         if (!strbuf_strip_suffix(&worktree_path, "/.git")) {
 122                 strbuf_reset(&worktree_path);
 123                 strbuf_add_absolute_path(&worktree_path, ".");
 124                 strbuf_strip_suffix(&worktree_path, "/.");
 125         }
 126
 127         strbuf_reset(&path);
 128         strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
 129
 130         if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
 131                 goto done;
 132
 133         worktree = xcalloc(1, sizeof(*worktree));
 134         worktree->path = strbuf_detach(&worktree_path, NULL);
 135         worktree->id = xstrdup(id);
 136         worktree->is_detached = is_detached;
 137         add_head_info(&head_ref, worktree);
 138
 139 done:
 140         strbuf_release(&path);
 141         strbuf_release(&worktree_path);
 142         strbuf_release(&head_ref);
 143         return worktree;
 144 }
 145
 146 static void mark_current_worktree(struct worktree **worktrees)
 147 {
 148         char *git_dir = xstrdup(absolute_path(get_git_dir()));
 149         int i;
 150
 151         for (i = 0; worktrees[i]; i++) {
 152                 struct worktree *wt = worktrees[i];
 153                 const char *wt_git_dir = get_worktree_git_dir(wt);
 154
 155                 if (!fspathcmp(git_dir, absolute_path(wt_git_dir))) {
 156                         wt->is_current = 1;
 157                         break;
 158                 }
 159         }
 160         free(git_dir);
 161 }
 162
 163 struct worktree **get_worktrees(void)
 164 {
 165         struct worktree **list = NULL;
 166         struct strbuf path = STRBUF_INIT;
 167         DIR *dir;
 168         struct dirent *d;
 169         int counter = 0, alloc = 2;
 170
 171         list = xmalloc(alloc * sizeof(struct worktree *));
 172
 173         list[counter++] = get_main_worktree();
 174
 175         strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
 176         dir = opendir(path.buf);
 177         strbuf_release(&path);
 178         if (dir) {
 179                 while ((d = readdir(dir)) != NULL) {
 180                         struct worktree *linked = NULL;
 181                         if (is_dot_or_dotdot(d->d_name))
 182                                 continue;
 183
 184                         if ((linked = get_linked_worktree(d->d_name))) {
 185                                 ALLOC_GROW(list, counter + 1, alloc);
 186                                 list[counter++] = linked;
 187                         }
 188                 }
 189                 closedir(dir);
 190         }
 191         ALLOC_GROW(list, counter + 1, alloc);
 192         list[counter] = NULL;
 193
 194         mark_current_worktree(list);
 195         return list;
 196 }
 197
 198 const char *get_worktree_git_dir(const struct worktree *wt)
 199 {
 200         if (!wt)
 201                 return get_git_dir();
 202         else if (!wt->id)
 203                 return get_git_common_dir();
 204         else
 205                 return git_common_path("worktrees/%s", wt->id);
 206 }
 207
 208 static struct worktree *find_worktree_by_suffix(struct worktree **list,
 209                                                 const char *suffix)
 210 {
 211         struct worktree *found = NULL;
 212         int nr_found = 0, suffixlen;
 213
 214         suffixlen = strlen(suffix);
 215         if (!suffixlen)
 216                 return NULL;
 217
 218         for (; *list && nr_found < 2; list++) {
 219                 const char      *path    = (*list)->path;
 220                 int              pathlen = strlen(path);
 221                 int              start   = pathlen - suffixlen;
 222
 223                 /* suffix must start at directory boundary */
 224                 if ((!start || (start > 0 && is_dir_sep(path[start - 1]))) &&
 225                     !fspathcmp(suffix, path + start)) {
 226                         found = *list;
 227                         nr_found++;
 228                 }
 229         }
 230         return nr_found == 1 ? found : NULL;
 231 }
 232
 233 struct worktree *find_worktree(struct worktree **list,
 234                                const char *prefix,
 235                                const char *arg)
 236 {
 237         struct worktree *wt;
 238         char *path;
 239
 240         if ((wt = find_worktree_by_suffix(list, arg)))
 241                 return wt;
 242
 243         arg = prefix_filename(prefix, strlen(prefix), arg);
 244         path = xstrdup(real_path(arg));
 245         for (; *list; list++)
 246                 if (!fspathcmp(path, real_path((*list)->path)))
 247                         break;
 248         free(path);
 249         return *list;
 250 }
 251
 252 int is_main_worktree(const struct worktree *wt)
 253 {
 254         return !wt->id;
 255 }
 256
 257 const char *is_worktree_locked(struct worktree *wt)
 258 {
 259         assert(!is_main_worktree(wt));
 260
 261         if (!wt->lock_reason_valid) {
 262                 struct strbuf path = STRBUF_INIT;
 263
 264                 strbuf_addstr(&path, worktree_git_path(wt, "locked"));
 265                 if (file_exists(path.buf)) {
 266                         struct strbuf lock_reason = STRBUF_INIT;
 267                         if (strbuf_read_file(&lock_reason, path.buf, 0) < 0)
 268                                 die_errno(_("failed to read '%s'"), path.buf);
 269                         strbuf_trim(&lock_reason);
 270                         wt->lock_reason = strbuf_detach(&lock_reason, NULL);
 271                 } else
 272                         wt->lock_reason = NULL;
 273                 wt->lock_reason_valid = 1;
 274                 strbuf_release(&path);
 275         }
 276
 277         return wt->lock_reason;
 278 }
 279
 280 int is_worktree_being_rebased(const struct worktree *wt,
 281                               const char *target)
 282 {
 283         struct wt_status_state state;
 284         int found_rebase;
 285
 286         memset(&state, 0, sizeof(state));
 287         found_rebase = wt_status_check_rebase(wt, &state) &&
 288                 ((state.rebase_in_progress ||
 289                   state.rebase_interactive_in_progress) &&
 290                  state.branch &&
 291                  starts_with(target, "refs/heads/") &&
 292                  !strcmp(state.branch, target + strlen("refs/heads/")));
 293         free(state.branch);
 294         free(state.onto);
 295         return found_rebase;
 296 }
 297
 298 int is_worktree_being_bisected(const struct worktree *wt,
 299                                const char *target)
 300 {
 301         struct wt_status_state state;
 302         int found_rebase;
 303
 304         memset(&state, 0, sizeof(state));
 305         found_rebase = wt_status_check_bisect(wt, &state) &&
 306                 state.branch &&
 307                 starts_with(target, "refs/heads/") &&
 308                 !strcmp(state.branch, target + strlen("refs/heads/"));
 309         free(state.branch);
 310         return found_rebase;
 311 }
 312
 313 /*
 314  * note: this function should be able to detect shared symref even if
 315  * HEAD is temporarily detached (e.g. in the middle of rebase or
 316  * bisect). New commands that do similar things should update this
 317  * function as well.
 318  */
 319 const struct worktree *find_shared_symref(const char *symref,
 320                                           const char *target)
 321 {
 322         const struct worktree *existing = NULL;
 323         struct strbuf path = STRBUF_INIT;
 324         struct strbuf sb = STRBUF_INIT;
 325         static struct worktree **worktrees;
 326         int i = 0;
 327
 328         if (worktrees)
 329                 free_worktrees(worktrees);
 330         worktrees = get_worktrees();
 331
 332         for (i = 0; worktrees[i]; i++) {
 333                 struct worktree *wt = worktrees[i];
 334                 if (wt->is_bare)
 335                         continue;
 336
 337                 if (wt->is_detached && !strcmp(symref, "HEAD")) {
 338                         if (is_worktree_being_rebased(wt, target)) {
 339                                 existing = wt;
 340                                 break;
 341                         }
 342                         if (is_worktree_being_bisected(wt, target)) {
 343                                 existing = wt;
 344                                 break;
 345                         }
 346                 }
 347
 348                 strbuf_reset(&path);
 349                 strbuf_reset(&sb);
 350                 strbuf_addf(&path, "%s/%s",
 351                             get_worktree_git_dir(wt),
 352                             symref);
 353
 354                 if (parse_ref(path.buf, &sb, NULL)) {
 355                         continue;
 356                 }
 357
 358                 if (!strcmp(sb.buf, target)) {
 359                         existing = wt;
 360                         break;
 361                 }
 362         }
 363
 364         strbuf_release(&path);
 365         strbuf_release(&sb);
 366
 367         return existing;
 368 }