config: factor out global config file retrieval

Factor out code that retrieves the global config file so that we can use
it in `gc.c` as well.

Use the old name from the previous commit since this function acts
functionally the same as `git_system_config` but for “global”.

Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/config.h b/config.h
index e5e523553c..5dba984f77 100644
--- a/config.h
+++ b/config.h
@@ -382,6 +382,7 @@ int config_error_nonbool(const char *);
 #endif
 
 char *git_system_config(void);
+char *git_global_config(void);
 void git_global_config_paths(char **user, char **xdg);
 
 int git_config_parse_parameter(const char *, config_fn_t fn, void *data);