clone: factor out checking for an alternate path

In a later patch we want to determine if a path is suitable as an
alternate from other commands than builtin/clone. Move the checking
functionality of `add_one_reference` to `compute_alternate_path` that is
defined in cache.h.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 9 insertions, 34 deletions

diff --git a/builtin/clone.c b/builtin/clone.c
index f044a8c27f..4cd3a6691a 100644
--- a/builtin/clone.c
+++ b/builtin/clone.c
@@ -282,44 +282,19 @@ static void strip_trailing_slashes(char *dir)
 
 static int add_one_reference(struct string_list_item *item, void *cb_data)
 {
-	char *ref_git;
-	const char *repo;
-	struct strbuf alternate = STRBUF_INIT;
-
-	/* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
-	ref_git = xstrdup(real_path(item->string));
-
-	repo = read_gitfile(ref_git);
-	if (!repo)
-		repo = read_gitfile(mkpath("%s/.git", ref_git));
-	if (repo) {
-		free(ref_git);
-		ref_git = xstrdup(repo);
-	}
-
-	if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
-		char *ref_git_git = mkpathdup("%s/.git", ref_git);
-		free(ref_git);
-		ref_git = ref_git_git;
-	} else if (!is_directory(mkpath("%s/objects", ref_git))) {
-		struct strbuf sb = STRBUF_INIT;
-		if (get_common_dir(&sb, ref_git))
-			die(_("reference repository '%s' as a linked checkout is not supported yet."),
-			    item->string);
-		die(_("reference repository '%s' is not a local repository."),
-		    item->string);
-	}
+	struct strbuf err = STRBUF_INIT;
+	struct strbuf sb = STRBUF_INIT;
+	char *ref_git = compute_alternate_path(item->string, &err);
 
-	if (!access(mkpath("%s/shallow", ref_git), F_OK))
-		die(_("reference repository '%s' is shallow"), item->string);
+	if (!ref_git)
+		die("%s", err.buf);
 
-	if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
-		die(_("reference repository '%s' is grafted"), item->string);
+	strbuf_addf(&sb, "%s/objects", ref_git);
+	add_to_alternates_file(sb.buf);
 
-	strbuf_addf(&alternate, "%s/objects", ref_git);
-	add_to_alternates_file(alternate.buf);
-	strbuf_release(&alternate);
 	free(ref_git);
+	strbuf_release(&err);
+	strbuf_release(&sb);
 	return 0;
 }