reset/checkout/read-tree: unify config callback for submodule recursion

The callback function is essentially duplicated 3 times. Remove all
of them and offer a new callback function, that lives in submodule.c

By putting the callback function there, we no longer need the function
'set_config_update_recurse_submodules', nor duplicate the global variable
in each builtin as well as submodule.c

In the three builtins we have different 2 ways how to load the .gitmodules
and config file, which are slightly different. git-checkout has to load
the submodule config all the time due to 23b4c7bcc5 (checkout: Use
submodule.*.ignore settings from .git/config and .gitmodules, 2010-08-28)

git-reset and git-read-tree do not respect these diff settings, so loading
the submodule configuration is optional. Also put that into submodule.c
for code deduplication.

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

1 files changed, 27 insertions, 6 deletions

diff --git a/submodule.c b/submodule.c
index 54825100b2..c9e764b519 100644
--- a/submodule.c
+++ b/submodule.c
@@ -18,7 +18,7 @@
 #include "worktree.h"
 
 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
-static int config_update_recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
+static int config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
 static int parallel_jobs = 1;
 static struct string_list changed_submodule_paths = STRING_LIST_INIT_DUP;
 static int initialized_fetch_ref_tips;
@@ -169,6 +169,32 @@ int submodule_config(const char *var, const char *value, void *cb)
 	return 0;
 }
 
+int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
+						     const char *arg, int unset)
+{
+	if (unset) {
+		config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
+		return 0;
+	}
+	if (arg)
+		config_update_recurse_submodules =
+			parse_update_recurse_submodules_arg(opt->long_name,
+							    arg);
+	else
+		config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
+
+	return 0;
+}
+
+void load_submodule_cache(void)
+{
+	if (config_update_recurse_submodules == RECURSE_SUBMODULES_OFF)
+		return;
+
+	gitmodules_config();
+	git_config(submodule_config, NULL);
+}
+
 void gitmodules_config(void)
 {
 	const char *work_tree = get_git_work_tree();
@@ -596,11 +622,6 @@ void set_config_fetch_recurse_submodules(int value)
 	config_fetch_recurse_submodules = value;
 }
 
-void set_config_update_recurse_submodules(int value)
-{
-	config_update_recurse_submodules = value;
-}
-
 int should_update_submodules(void)
 {
 	return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;