introduce "extensions" form of core.repositoryformatversion

diff --git a/setup.c b/setup.c
index 82c0cc2a13bfeae3ec364dce2438fb4c67e46a35..0d5384683ce2e48268e3298dbff18daedabc9513 100644 (file)
--- a/setup.c
+++ b/setup.c
@@ -5,6 +5,7 @@
 static int inside_git_dir = -1;
 static int inside_work_tree = -1;
 static int work_tree_config_is_bogus;
+static struct string_list unknown_extensions = STRING_LIST_INIT_DUP;
 
 /*
  * The input parameter must contain an absolute path, and it must already be
@@ -352,10 +353,23 @@ void setup_work_tree(void)
 
 static int check_repo_format(const char *var, const char *value, void *cb)
 {
+       const char *ext;
+
        if (strcmp(var, "core.repositoryformatversion") == 0)
                repository_format_version = git_config_int(var, value);
        else if (strcmp(var, "core.sharedrepository") == 0)
                shared_repository = git_config_perm(var, value);
+       else if (skip_prefix(var, "extensions.", &ext)) {
+               /*
+                * record any known extensions here; otherwise,
+                * we fall through to recording it as unknown, and
+                * check_repository_format will complain
+                */
+               if (!strcmp(ext, "noop"))
+                       ;
+               else
+                       string_list_append(&unknown_extensions, ext);
+       }
        return 0;
 }
 
@@ -366,6 +380,8 @@ static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
        config_fn_t fn;
        int ret = 0;
 
+       string_list_clear(&unknown_extensions, 0);
+
        if (get_common_dir(&sb, gitdir))
                fn = check_repo_format;
        else
@@ -383,16 +399,31 @@ static int check_repository_format_gently(const char *gitdir, int *nongit_ok)
         * is a good one.
         */
        git_config_early(fn, NULL, repo_config);
-       if (GIT_REPO_VERSION < repository_format_version) {
+       if (GIT_REPO_VERSION_READ < repository_format_version) {
                if (!nongit_ok)
                        die ("Expected git repo version <= %d, found %d",
-                            GIT_REPO_VERSION, repository_format_version);
+                            GIT_REPO_VERSION_READ, repository_format_version);
                warning("Expected git repo version <= %d, found %d",
-                       GIT_REPO_VERSION, repository_format_version);
+                       GIT_REPO_VERSION_READ, repository_format_version);
                warning("Please upgrade Git");
                *nongit_ok = -1;
                ret = -1;
        }
+
+       if (repository_format_version >= 1 && unknown_extensions.nr) {
+               int i;
+
+               if (!nongit_ok)
+                       die("unknown repository extension: %s",
+                           unknown_extensions.items[0].string);
+
+               for (i = 0; i < unknown_extensions.nr; i++)
+                       warning("unknown repository extension: %s",
+                               unknown_extensions.items[i].string);
+               *nongit_ok = -1;
+               ret = -1;
+       }
+
        strbuf_release(&sb);
        return ret;
 }