[PATCH] remote: check config validity before creating rewrite struct

When parsing url.foo.insteadOf, we call make_rewrite() and only then
check to make sure the value is a string (and return an error if it
isn't). This isn't quite a leak, because the struct we allocate is part
of a global array, but it does leave a funny half-finished struct.

In practice, it doesn't make much difference because we exit soon after
due to the config error anyway. But let's flip the order here to avoid
leaving a trap for somebody in the future.

Signed-off-by: Jeff King <redacted>
---
This was a minor cleanup I mentioned in:

  https://public-inbox.org/git/20181122173109.GI28192@sigill.intra.peff.net/

but didn't get picked up.

 remote.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/remote.c b/remote.c
index 670dd44813..9cc3b07d21 100644
--- a/remote.c
+++ b/remote.c

@@ -337,14 +337,14 @@ static int handle_config(const char *key, const char *value, void *cb)
 		if (!name)
 			return 0;
 		if (!strcmp(subkey, "insteadof")) {
-			rewrite = make_rewrite(&rewrites, name, namelen);
 			if (!value)
 				return config_error_nonbool(key);
+			rewrite = make_rewrite(&rewrites, name, namelen);
 			add_instead_of(rewrite, xstrdup(value));
 		} else if (!strcmp(subkey, "pushinsteadof")) {
-			rewrite = make_rewrite(&rewrites_push, name, namelen);
 			if (!value)
 				return config_error_nonbool(key);
+			rewrite = make_rewrite(&rewrites_push, name, namelen);
 			add_instead_of(rewrite, xstrdup(value));
 		}
 	}

-- 
2.20.1.651.g2d41a78c67