log: add option to choose which refs to decorate

diff --git a/sha1_file.c b/sha1_file.c
index d7089813762513254b8fe48199a57ecdeb8600f3..8a7c6b7eba8ab2f829c4504b9db4578c0daac25a 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -404,6 +404,9 @@ static void link_alt_odb_entries(const char *alt, int sep,
        struct strbuf objdirbuf = STRBUF_INIT;
        struct strbuf entry = STRBUF_INIT;
 
+       if (!alt || !*alt)
+               return;
+
        if (depth > 5) {
                error("%s: ignoring alternate object stores, nesting too deep.",
                                relative_base);
@@ -604,7 +607,6 @@ void prepare_alt_odb(void)
                return;
 
        alt = getenv(ALTERNATE_DB_ENVIRONMENT);
-       if (!alt) alt = "";
 
        alt_odb_tail = &alt_odb_list;
        link_alt_odb_entries(alt, PATH_SEP, NULL, 0);