worktree.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "strbuf.h"
   4 #include "worktree.h"
   5
   6 void free_worktrees(struct worktree **worktrees)
   7 {
   8         int i = 0;
   9
  10         for (i = 0; worktrees[i]; i++) {
  11                 free(worktrees[i]->path);
  12                 free(worktrees[i]->id);
  13                 free(worktrees[i]->head_ref);
  14                 free(worktrees[i]);
  15         }
  16         free (worktrees);
  17 }
  18
  19 /*
  20  * read 'path_to_ref' into 'ref'.  Also if is_detached is not NULL,
  21  * set is_detached to 1 (0) if the ref is detatched (is not detached).
  22  *
  23  * $GIT_COMMON_DIR/$symref (e.g. HEAD) is practically outside $GIT_DIR so
  24  * for linked worktrees, `resolve_ref_unsafe()` won't work (it uses
  25  * git_path). Parse the ref ourselves.
  26  *
  27  * return -1 if the ref is not a proper ref, 0 otherwise (success)
  28  */
  29 static int parse_ref(char *path_to_ref, struct strbuf *ref, int *is_detached)
  30 {
  31         if (is_detached)
  32                 *is_detached = 0;
  33         if (!strbuf_readlink(ref, path_to_ref, 0)) {
  34                 /* HEAD is symbolic link */
  35                 if (!starts_with(ref->buf, "refs/") ||
  36                                 check_refname_format(ref->buf, 0))
  37                         return -1;
  38         } else if (strbuf_read_file(ref, path_to_ref, 0) >= 0) {
  39                 /* textual symref or detached */
  40                 if (!starts_with(ref->buf, "ref:")) {
  41                         if (is_detached)
  42                                 *is_detached = 1;
  43                 } else {
  44                         strbuf_remove(ref, 0, strlen("ref:"));
  45                         strbuf_trim(ref);
  46                         if (check_refname_format(ref->buf, 0))
  47                                 return -1;
  48                 }
  49         } else
  50                 return -1;
  51         return 0;
  52 }
  53
  54 /**
  55  * Add the head_sha1 and head_ref (if not detached) to the given worktree
  56  */
  57 static void add_head_info(struct strbuf *head_ref, struct worktree *worktree)
  58 {
  59         if (head_ref->len) {
  60                 if (worktree->is_detached) {
  61                         get_sha1_hex(head_ref->buf, worktree->head_sha1);
  62                 } else {
  63                         resolve_ref_unsafe(head_ref->buf, 0, worktree->head_sha1, NULL);
  64                         worktree->head_ref = strbuf_detach(head_ref, NULL);
  65                 }
  66         }
  67 }
  68
  69 /**
  70  * get the main worktree
  71  */
  72 static struct worktree *get_main_worktree(void)
  73 {
  74         struct worktree *worktree = NULL;
  75         struct strbuf path = STRBUF_INIT;
  76         struct strbuf worktree_path = STRBUF_INIT;
  77         struct strbuf head_ref = STRBUF_INIT;
  78         int is_bare = 0;
  79         int is_detached = 0;
  80
  81         strbuf_addstr(&worktree_path, absolute_path(get_git_common_dir()));
  82         is_bare = !strbuf_strip_suffix(&worktree_path, "/.git");
  83         if (is_bare)
  84                 strbuf_strip_suffix(&worktree_path, "/.");
  85
  86         strbuf_addf(&path, "%s/HEAD", get_git_common_dir());
  87
  88         if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
  89                 goto done;
  90
  91         worktree = xmalloc(sizeof(struct worktree));
  92         worktree->path = strbuf_detach(&worktree_path, NULL);
  93         worktree->id = NULL;
  94         worktree->is_bare = is_bare;
  95         worktree->head_ref = NULL;
  96         worktree->is_detached = is_detached;
  97         add_head_info(&head_ref, worktree);
  98
  99 done:
 100         strbuf_release(&path);
 101         strbuf_release(&worktree_path);
 102         strbuf_release(&head_ref);
 103         return worktree;
 104 }
 105
 106 static struct worktree *get_linked_worktree(const char *id)
 107 {
 108         struct worktree *worktree = NULL;
 109         struct strbuf path = STRBUF_INIT;
 110         struct strbuf worktree_path = STRBUF_INIT;
 111         struct strbuf head_ref = STRBUF_INIT;
 112         int is_detached = 0;
 113
 114         if (!id)
 115                 die("Missing linked worktree name");
 116
 117         strbuf_git_common_path(&path, "worktrees/%s/gitdir", id);
 118         if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
 119                 /* invalid gitdir file */
 120                 goto done;
 121
 122         strbuf_rtrim(&worktree_path);
 123         if (!strbuf_strip_suffix(&worktree_path, "/.git")) {
 124                 strbuf_reset(&worktree_path);
 125                 strbuf_addstr(&worktree_path, absolute_path("."));
 126                 strbuf_strip_suffix(&worktree_path, "/.");
 127         }
 128
 129         strbuf_reset(&path);
 130         strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
 131
 132         if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
 133                 goto done;
 134
 135         worktree = xmalloc(sizeof(struct worktree));
 136         worktree->path = strbuf_detach(&worktree_path, NULL);
 137         worktree->id = xstrdup(id);
 138         worktree->is_bare = 0;
 139         worktree->head_ref = NULL;
 140         worktree->is_detached = is_detached;
 141         add_head_info(&head_ref, worktree);
 142
 143 done:
 144         strbuf_release(&path);
 145         strbuf_release(&worktree_path);
 146         strbuf_release(&head_ref);
 147         return worktree;
 148 }
 149
 150 struct worktree **get_worktrees(void)
 151 {
 152         struct worktree **list = NULL;
 153         struct strbuf path = STRBUF_INIT;
 154         DIR *dir;
 155         struct dirent *d;
 156         int counter = 0, alloc = 2;
 157
 158         list = xmalloc(alloc * sizeof(struct worktree *));
 159
 160         if ((list[counter] = get_main_worktree()))
 161                 counter++;
 162
 163         strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
 164         dir = opendir(path.buf);
 165         strbuf_release(&path);
 166         if (dir) {
 167                 while ((d = readdir(dir)) != NULL) {
 168                         struct worktree *linked = NULL;
 169                         if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
 170                                 continue;
 171
 172                         if ((linked = get_linked_worktree(d->d_name))) {
 173                                 ALLOC_GROW(list, counter + 1, alloc);
 174                                 list[counter++] = linked;
 175                         }
 176                 }
 177                 closedir(dir);
 178         }
 179         ALLOC_GROW(list, counter + 1, alloc);
 180         list[counter] = NULL;
 181         return list;
 182 }
 183
 184 const char *get_worktree_git_dir(const struct worktree *wt)
 185 {
 186         if (!wt)
 187                 return get_git_dir();
 188         else if (!wt->id)
 189                 return get_git_common_dir();
 190         else
 191                 return git_common_path("worktrees/%s", wt->id);
 192 }
 193
 194 char *find_shared_symref(const char *symref, const char *target)
 195 {
 196         char *existing = NULL;
 197         struct strbuf path = STRBUF_INIT;
 198         struct strbuf sb = STRBUF_INIT;
 199         struct worktree **worktrees = get_worktrees();
 200         int i = 0;
 201
 202         for (i = 0; worktrees[i]; i++) {
 203                 strbuf_reset(&path);
 204                 strbuf_reset(&sb);
 205                 strbuf_addf(&path, "%s/%s",
 206                             get_worktree_git_dir(worktrees[i]),
 207                             symref);
 208
 209                 if (parse_ref(path.buf, &sb, NULL)) {
 210                         continue;
 211                 }
 212
 213                 if (!strcmp(sb.buf, target)) {
 214                         existing = xstrdup(worktrees[i]->path);
 215                         break;
 216                 }
 217         }
 218
 219         strbuf_release(&path);
 220         strbuf_release(&sb);
 221         free_worktrees(worktrees);
 222
 223         return existing;
 224 }