Fix saving remotes with several fetch/push ref specs.

At some moment git_config_delete_entry lost the ability to delete one entry of
a multivar configuration. The moment you had more than one fetch or push
ref spec for a remote you will not be able to save that remote anymore. The
changes in network::remote::remotes::save show that problem.

I needed to create a new git_config_delete_multivar because I was not able to
remove one or several entries of a multivar config with the current API.
Several tries modifying how git_config_set_multivar(..., NULL) behaved were
not successful.

git_config_delete_multivar is very similar to git_config_set_multivar, and
delegates into config_delete_multivar of config_file. This function search
for the cvar_t that will be deleted, storing them in a temporal array, and
rebuilding the linked list. After calling config_write to delete the entries,
the cvar_t stored in the temporal array are freed.

There is a little fix in config_write, it avoids an infinite loop when using
a regular expression (case for the multivars). This error was found by the
test network::remote::remotes::tagopt.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/remote.c b/src/remote.c
index bdfa08642..e2b40347a 100644
--- a/src/remote.c
+++ b/src/remote.c
@@ -365,16 +365,18 @@ static int update_config_refspec(const git_remote *remote, git_config *config, i
 	const char *dir;
 	size_t i;
 	int error = 0;
+	const char *cname;
 
 	push = direction == GIT_DIRECTION_PUSH;
 	dir = push ? "push" : "fetch";
 
 	if (git_buf_printf(&name, "remote.%s.%s", remote->name, dir) < 0)
 		return -1;
+	cname = git_buf_cstr(&name);
 
 	/* Clear out the existing config */
 	while (!error)
-		error = git_config_delete_entry(config, git_buf_cstr(&name));
+		error = git_config_delete_multivar(config, cname, ".*");
 
 	if (error != GIT_ENOTFOUND)
 		return error;
@@ -386,7 +388,7 @@ static int update_config_refspec(const git_remote *remote, git_config *config, i
 			continue;
 
 		if ((error = git_config_set_multivar(
-				config, git_buf_cstr(&name), "", spec->string)) < 0) {
+				config, cname, "", spec->string)) < 0) {
 			goto cleanup;
 		}
 	}