1 files changed, 147 insertions, 76 deletions

diff --git a/worktree.c b/worktree.c
index 89a81b13de..28989cf06e 100644
--- a/worktree.c
+++ b/worktree.c
@@ -1,4 +1,5 @@
 #include "cache.h"
+#include "repository.h"
 #include "refs.h"
 #include "strbuf.h"
 #include "worktree.h"
@@ -19,54 +20,25 @@ void free_worktrees(struct worktree **worktrees)
 	free (worktrees);
 }
 
-/*
- * read 'path_to_ref' into 'ref'.  Also if is_detached is not NULL,
- * set is_detached to 1 (0) if the ref is detached (is not detached).
- *
- * $GIT_COMMON_DIR/$symref (e.g. HEAD) is practically outside $GIT_DIR so
- * for linked worktrees, `resolve_ref_unsafe()` won't work (it uses
- * git_path). Parse the ref ourselves.
- *
- * return -1 if the ref is not a proper ref, 0 otherwise (success)
- */
-static int parse_ref(char *path_to_ref, struct strbuf *ref, int *is_detached)
-{
-	if (is_detached)
-		*is_detached = 0;
-	if (!strbuf_readlink(ref, path_to_ref, 0)) {
-		/* HEAD is symbolic link */
-		if (!starts_with(ref->buf, "refs/") ||
-				check_refname_format(ref->buf, 0))
-			return -1;
-	} else if (strbuf_read_file(ref, path_to_ref, 0) >= 0) {
-		/* textual symref or detached */
-		if (!starts_with(ref->buf, "ref:")) {
-			if (is_detached)
-				*is_detached = 1;
-		} else {
-			strbuf_remove(ref, 0, strlen("ref:"));
-			strbuf_trim(ref);
-			if (check_refname_format(ref->buf, 0))
-				return -1;
-		}
-	} else
-		return -1;
-	return 0;
-}
-
 /**
- * Add the head_sha1 and head_ref (if not detached) to the given worktree
+ * Update head_sha1, head_ref and is_detached of the given worktree
  */
-static void add_head_info(struct strbuf *head_ref, struct worktree *worktree)
+static void add_head_info(struct worktree *wt)
 {
-	if (head_ref->len) {
-		if (worktree->is_detached) {
-			get_sha1_hex(head_ref->buf, worktree->head_sha1);
-		} else {
-			resolve_ref_unsafe(head_ref->buf, 0, worktree->head_sha1, NULL);
-			worktree->head_ref = strbuf_detach(head_ref, NULL);
-		}
-	}
+	int flags;
+	const char *target;
+
+	target = refs_resolve_ref_unsafe(get_worktree_ref_store(wt),
+					 "HEAD",
+					 0,
+					 &wt->head_oid, &flags);
+	if (!target)
+		return;
+
+	if (flags & REF_ISSYMREF)
+		wt->head_ref = xstrdup(target);
+	else
+		wt->is_detached = 1;
 }
 
 /**
@@ -77,9 +49,7 @@ static struct worktree *get_main_worktree(void)
 	struct worktree *worktree = NULL;
 	struct strbuf path = STRBUF_INIT;
 	struct strbuf worktree_path = STRBUF_INIT;
-	struct strbuf head_ref = STRBUF_INIT;
 	int is_bare = 0;
-	int is_detached = 0;
 
 	strbuf_add_absolute_path(&worktree_path, get_git_common_dir());
 	is_bare = !strbuf_strip_suffix(&worktree_path, "/.git");
@@ -91,13 +61,10 @@ static struct worktree *get_main_worktree(void)
 	worktree = xcalloc(1, sizeof(*worktree));
 	worktree->path = strbuf_detach(&worktree_path, NULL);
 	worktree->is_bare = is_bare;
-	worktree->is_detached = is_detached;
-	if (!parse_ref(path.buf, &head_ref, &is_detached))
-		add_head_info(&head_ref, worktree);
+	add_head_info(worktree);
 
 	strbuf_release(&path);
 	strbuf_release(&worktree_path);
-	strbuf_release(&head_ref);
 	return worktree;
 }
 
@@ -106,13 +73,11 @@ static struct worktree *get_linked_worktree(const char *id)
 	struct worktree *worktree = NULL;
 	struct strbuf path = STRBUF_INIT;
 	struct strbuf worktree_path = STRBUF_INIT;
-	struct strbuf head_ref = STRBUF_INIT;
-	int is_detached = 0;
 
 	if (!id)
 		die("Missing linked worktree name");
 
-	strbuf_git_common_path(&path, "worktrees/%s/gitdir", id);
+	strbuf_git_common_path(&path, the_repository, "worktrees/%s/gitdir", id);
 	if (strbuf_read_file(&worktree_path, path.buf, 0) <= 0)
 		/* invalid gitdir file */
 		goto done;
@@ -127,19 +92,14 @@ static struct worktree *get_linked_worktree(const char *id)
 	strbuf_reset(&path);
 	strbuf_addf(&path, "%s/worktrees/%s/HEAD", get_git_common_dir(), id);
 
-	if (parse_ref(path.buf, &head_ref, &is_detached) < 0)
-		goto done;
-
 	worktree = xcalloc(1, sizeof(*worktree));
 	worktree->path = strbuf_detach(&worktree_path, NULL);
 	worktree->id = xstrdup(id);
-	worktree->is_detached = is_detached;
-	add_head_info(&head_ref, worktree);
+	add_head_info(worktree);
 
 done:
 	strbuf_release(&path);
 	strbuf_release(&worktree_path);
-	strbuf_release(&head_ref);
 	return worktree;
 }
 
@@ -294,6 +254,102 @@ const char *is_worktree_locked(struct worktree *wt)
 	return wt->lock_reason;
 }
 
+/* convenient wrapper to deal with NULL strbuf */
+static void strbuf_addf_gently(struct strbuf *buf, const char *fmt, ...)
+{
+	va_list params;
+
+	if (!buf)
+		return;
+
+	va_start(params, fmt);
+	strbuf_vaddf(buf, fmt, params);
+	va_end(params);
+}
+
+int validate_worktree(const struct worktree *wt, struct strbuf *errmsg,
+		      unsigned flags)
+{
+	struct strbuf wt_path = STRBUF_INIT;
+	char *path = NULL;
+	int err, ret = -1;
+
+	strbuf_addf(&wt_path, "%s/.git", wt->path);
+
+	if (is_main_worktree(wt)) {
+		if (is_directory(wt_path.buf)) {
+			ret = 0;
+			goto done;
+		}
+		/*
+		 * Main worktree using .git file to point to the
+		 * repository would make it impossible to know where
+		 * the actual worktree is if this function is executed
+		 * from another worktree. No .git file support for now.
+		 */
+		strbuf_addf_gently(errmsg,
+				   _("'%s' at main working tree is not the repository directory"),
+				   wt_path.buf);
+		goto done;
+	}
+
+	/*
+	 * Make sure "gitdir" file points to a real .git file and that
+	 * file points back here.
+	 */
+	if (!is_absolute_path(wt->path)) {
+		strbuf_addf_gently(errmsg,
+				   _("'%s' file does not contain absolute path to the working tree location"),
+				   git_common_path("worktrees/%s/gitdir", wt->id));
+		goto done;
+	}
+
+	if (flags & WT_VALIDATE_WORKTREE_MISSING_OK &&
+	    !file_exists(wt->path)) {
+		ret = 0;
+		goto done;
+	}
+
+	if (!file_exists(wt_path.buf)) {
+		strbuf_addf_gently(errmsg, _("'%s' does not exist"), wt_path.buf);
+		goto done;
+	}
+
+	path = xstrdup_or_null(read_gitfile_gently(wt_path.buf, &err));
+	if (!path) {
+		strbuf_addf_gently(errmsg, _("'%s' is not a .git file, error code %d"),
+				   wt_path.buf, err);
+		goto done;
+	}
+
+	ret = fspathcmp(path, real_path(git_common_path("worktrees/%s", wt->id)));
+
+	if (ret)
+		strbuf_addf_gently(errmsg, _("'%s' does not point back to '%s'"),
+				   wt->path, git_common_path("worktrees/%s", wt->id));
+done:
+	free(path);
+	strbuf_release(&wt_path);
+	return ret;
+}
+
+void update_worktree_location(struct worktree *wt, const char *path_)
+{
+	struct strbuf path = STRBUF_INIT;
+
+	if (is_main_worktree(wt))
+		die("BUG: can't relocate main worktree");
+
+	strbuf_realpath(&path, path_, 1);
+	if (fspathcmp(wt->path, path.buf)) {
+		write_file(git_common_path("worktrees/%s/gitdir", wt->id),
+			   "%s/.git", path.buf);
+		free(wt->path);
+		wt->path = strbuf_detach(&path, NULL);
+	}
+	strbuf_release(&path);
+}
+
 int is_worktree_being_rebased(const struct worktree *wt,
 			      const char *target)
 {
@@ -337,8 +393,6 @@ const struct worktree *find_shared_symref(const char *symref,
 					  const char *target)
 {
 	const struct worktree *existing = NULL;
-	struct strbuf path = STRBUF_INIT;
-	struct strbuf sb = STRBUF_INIT;
 	static struct worktree **worktrees;
 	int i = 0;
 
@@ -348,6 +402,10 @@ const struct worktree *find_shared_symref(const char *symref,
 
 	for (i = 0; worktrees[i]; i++) {
 		struct worktree *wt = worktrees[i];
+		const char *symref_target;
+		struct ref_store *refs;
+		int flags;
+
 		if (wt->is_bare)
 			continue;
 
@@ -362,25 +420,16 @@ const struct worktree *find_shared_symref(const char *symref,
 			}
 		}
 
-		strbuf_reset(&path);
-		strbuf_reset(&sb);
-		strbuf_addf(&path, "%s/%s",
-			    get_worktree_git_dir(wt),
-			    symref);
-
-		if (parse_ref(path.buf, &sb, NULL)) {
-			continue;
-		}
-
-		if (!strcmp(sb.buf, target)) {
+		refs = get_worktree_ref_store(wt);
+		symref_target = refs_resolve_ref_unsafe(refs, symref, 0,
+							NULL, &flags);
+		if ((flags & REF_ISSYMREF) &&
+		    symref_target && !strcmp(symref_target, target)) {
 			existing = wt;
 			break;
 		}
 	}
 
-	strbuf_release(&path);
-	strbuf_release(&sb);
-
 	return existing;
 }
 
@@ -433,3 +482,25 @@ int submodule_uses_worktrees(const char *path)
 	closedir(dir);
 	return ret;
 }
+
+int other_head_refs(each_ref_fn fn, void *cb_data)
+{
+	struct worktree **worktrees, **p;
+	int ret = 0;
+
+	worktrees = get_worktrees(0);
+	for (p = worktrees; *p; p++) {
+		struct worktree *wt = *p;
+		struct ref_store *refs;
+
+		if (wt->is_current)
+			continue;
+
+		refs = get_worktree_ref_store(wt);
+		ret = refs_head_ref(refs, fn, cb_data);
+		if (ret)
+			break;
+	}
+	free_worktrees(worktrees);
+	return ret;
+}