config: clarify memory ownership in `git_config_string()`

The out parameter of `git_config_string()` is a `const char **` even
though we transfer ownership of memory to the caller. This is quite
misleading and has led to many memory leaks all over the place. Adapt
the parameter to instead be `char **`.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/config.c b/config.c
index f9101045ee..da52a7f8a1 100644
--- a/config.c
+++ b/config.c
@@ -1338,7 +1338,7 @@ int git_config_bool(const char *name, const char *value)
 	return v;
 }
 
-int git_config_string(const char **dest, const char *var, const char *value)
+int git_config_string(char **dest, const char *var, const char *value)
 {
 	if (!value)
 		return config_error_nonbool(var);
@@ -1566,7 +1566,7 @@ static int git_default_core_config(const char *var, const char *value,
 
 	if (!strcmp(var, "core.checkroundtripencoding")) {
 		FREE_AND_NULL(check_roundtrip_encoding);
-		return git_config_string((const char **) &check_roundtrip_encoding, var, value);
+		return git_config_string(&check_roundtrip_encoding, var, value);
 	}
 
 	if (!strcmp(var, "core.notesref")) {
@@ -2418,7 +2418,7 @@ int git_configset_get_string(struct config_set *set, const char *key, char **des
 {
 	const char *value;
 	if (!git_configset_get_value(set, key, &value, NULL))
-		return git_config_string((const char **)dest, key, value);
+		return git_config_string(dest, key, value);
 	else
 		return 1;
 }