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 detached (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_add_absolute_path(&worktree_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_add_absolute_path(&worktree_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 int is_worktree_being_rebased(const struct worktree *wt,
 218                               const char *target)
 219 {
 220         struct wt_status_state state;
 221         int found_rebase;
 222
 223         memset(&state, 0, sizeof(state));
 224         found_rebase = wt_status_check_rebase(wt, &state) &&
 225                 ((state.rebase_in_progress ||
 226                   state.rebase_interactive_in_progress) &&
 227                  state.branch &&
 228                  starts_with(target, "refs/heads/") &&
 229                  !strcmp(state.branch, target + strlen("refs/heads/")));
 230         free(state.branch);
 231         free(state.onto);
 232         return found_rebase;
 233 }
 234
 235 int is_worktree_being_bisected(const struct worktree *wt,
 236                                const char *target)
 237 {
 238         struct wt_status_state state;
 239         int found_rebase;
 240
 241         memset(&state, 0, sizeof(state));
 242         found_rebase = wt_status_check_bisect(wt, &state) &&
 243                 state.branch &&
 244                 starts_with(target, "refs/heads/") &&
 245                 !strcmp(state.branch, target + strlen("refs/heads/"));
 246         free(state.branch);
 247         return found_rebase;
 248 }
 249
 250 /*
 251  * note: this function should be able to detect shared symref even if
 252  * HEAD is temporarily detached (e.g. in the middle of rebase or
 253  * bisect). New commands that do similar things should update this
 254  * function as well.
 255  */
 256 const struct worktree *find_shared_symref(const char *symref,
 257                                           const char *target)
 258 {
 259         const struct worktree *existing = NULL;
 260         struct strbuf path = STRBUF_INIT;
 261         struct strbuf sb = STRBUF_INIT;
 262         static struct worktree **worktrees;
 263         int i = 0;
 264
 265         if (worktrees)
 266                 free_worktrees(worktrees);
 267         worktrees = get_worktrees();
 268
 269         for (i = 0; worktrees[i]; i++) {
 270                 struct worktree *wt = worktrees[i];
 271
 272                 if (wt->is_detached && !strcmp(symref, "HEAD")) {
 273                         if (is_worktree_being_rebased(wt, target)) {
 274                                 existing = wt;
 275                                 break;
 276                         }
 277                         if (is_worktree_being_bisected(wt, target)) {
 278                                 existing = wt;
 279                                 break;
 280                         }
 281                 }
 282
 283                 strbuf_reset(&path);
 284                 strbuf_reset(&sb);
 285                 strbuf_addf(&path, "%s/%s",
 286                             get_worktree_git_dir(wt),
 287                             symref);
 288
 289                 if (parse_ref(path.buf, &sb, NULL)) {
 290                         continue;
 291                 }
 292
 293                 if (!strcmp(sb.buf, target)) {
 294                         existing = wt;
 295                         break;
 296                 }
 297         }
 298
 299         strbuf_release(&path);
 300         strbuf_release(&sb);
 301
 302         return existing;
 303 }