doc: revisions - clarify reachability examples
[gitweb.git] / branch.c
index b0024353f4409c8b54c4b569b8fb7c435b26cdae..d013374e5a0b5714836be77709b07a5e3f67ed2a 100644 (file)
--- a/branch.c
+++ b/branch.c
@@ -302,11 +302,100 @@ void create_branch(const char *head,
 
 void remove_branch_state(void)
 {
-       unlink(git_path("CHERRY_PICK_HEAD"));
-       unlink(git_path("REVERT_HEAD"));
-       unlink(git_path("MERGE_HEAD"));
-       unlink(git_path("MERGE_RR"));
-       unlink(git_path("MERGE_MSG"));
-       unlink(git_path("MERGE_MODE"));
-       unlink(git_path("SQUASH_MSG"));
+       unlink(git_path_cherry_pick_head());
+       unlink(git_path_revert_head());
+       unlink(git_path_merge_head());
+       unlink(git_path_merge_rr());
+       unlink(git_path_merge_msg());
+       unlink(git_path_merge_mode());
+       unlink(git_path_squash_msg());
+}
+
+static char *find_linked_symref(const char *symref, const char *branch,
+                               const char *id)
+{
+       struct strbuf sb = STRBUF_INIT;
+       struct strbuf path = STRBUF_INIT;
+       struct strbuf gitdir = STRBUF_INIT;
+       char *existing = NULL;
+
+       /*
+        * $GIT_COMMON_DIR/$symref (e.g. HEAD) is practically outside
+        * $GIT_DIR so resolve_ref_unsafe() won't work (it uses
+        * git_path). Parse the ref ourselves.
+        */
+       if (id)
+               strbuf_addf(&path, "%s/worktrees/%s/%s", get_git_common_dir(), id, symref);
+       else
+               strbuf_addf(&path, "%s/%s", get_git_common_dir(), symref);
+
+       if (!strbuf_readlink(&sb, path.buf, 0)) {
+               if (!starts_with(sb.buf, "refs/") ||
+                   check_refname_format(sb.buf, 0))
+                       goto done;
+       } else if (strbuf_read_file(&sb, path.buf, 0) >= 0 &&
+           starts_with(sb.buf, "ref:")) {
+               strbuf_remove(&sb, 0, strlen("ref:"));
+               strbuf_trim(&sb);
+       } else
+               goto done;
+       if (strcmp(sb.buf, branch))
+               goto done;
+       if (id) {
+               strbuf_reset(&path);
+               strbuf_addf(&path, "%s/worktrees/%s/gitdir", get_git_common_dir(), id);
+               if (strbuf_read_file(&gitdir, path.buf, 0) <= 0)
+                       goto done;
+               strbuf_rtrim(&gitdir);
+       } else
+               strbuf_addstr(&gitdir, get_git_common_dir());
+       strbuf_strip_suffix(&gitdir, ".git");
+
+       existing = strbuf_detach(&gitdir, NULL);
+done:
+       strbuf_release(&path);
+       strbuf_release(&sb);
+       strbuf_release(&gitdir);
+
+       return existing;
+}
+
+char *find_shared_symref(const char *symref, const char *target)
+{
+       struct strbuf path = STRBUF_INIT;
+       DIR *dir;
+       struct dirent *d;
+       char *existing;
+
+       if ((existing = find_linked_symref(symref, target, NULL)))
+               return existing;
+
+       strbuf_addf(&path, "%s/worktrees", get_git_common_dir());
+       dir = opendir(path.buf);
+       strbuf_release(&path);
+       if (!dir)
+               return NULL;
+
+       while ((d = readdir(dir)) != NULL) {
+               if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
+                       continue;
+               existing = find_linked_symref(symref, target, d->d_name);
+               if (existing)
+                       goto done;
+       }
+done:
+       closedir(dir);
+
+       return existing;
+}
+
+void die_if_checked_out(const char *branch)
+{
+       char *existing;
+
+       existing = find_shared_symref("HEAD", branch);
+       if (existing) {
+               skip_prefix(branch, "refs/heads/", &branch);
+               die(_("'%s' is already checked out at '%s'"), branch, existing);
+       }
 }