[PATCH] remote: plug memory leaks

[Junio C Hamano <gitster@pobox.com>]

The in-core data structure used to keep track of
'url.<real>.{insteadOf,pushInsteadOf} = <alias>' settings is not
properly cleaned up when the process is done with it.

Fix the rewrites_release() function to free not just the 'struct
rewrites' instance itself, but also allocated structures that are
pointed at by the 'struct rewrites' instance.  One of the embedded
structures holds a 'const char *' to point at a borrowed constant
string from a configuration callback.  Since the code does not
modify this string, stop copying the value (alias URL) before
registering it in 'struct rewrite', as nobody is freeing this
member, to avoid leaking the extra copy.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

 * These are not recently introduced leaks as far as I can tell, but
   the new tests in en/submodule-insteadof-remote-match expose them.

 remote.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/remote.c b/remote.c
index 368a43c1b2..e3d4b25040 100644
--- a/remote.c
+++ b/remote.c
@@ -309,8 +309,11 @@ static struct rewrite *make_rewrite(struct rewrites *r,
 
 static void rewrites_release(struct rewrites *r)
 {
-	for (int i = 0; i < r->rewrite_nr; i++)
+	for (int i = 0; i < r->rewrite_nr; i++) {
 		free((char *)r->rewrite[i]->base);
+		free(r->rewrite[i]->instead_of);
+		free(r->rewrite[i]);
+	}
 	free(r->rewrite);
 	memset(r, 0, sizeof(*r));
 }
@@ -469,13 +472,13 @@ static int handle_config(const char *key, const char *value,
 				return config_error_nonbool(key);
 			rewrite = make_rewrite(&remote_state->rewrites, name,
 					       namelen);
-			add_instead_of(rewrite, xstrdup(value));
+			add_instead_of(rewrite, value);
 		} else if (!strcmp(subkey, "pushinsteadof")) {
 			if (!value)
 				return config_error_nonbool(key);
 			rewrite = make_rewrite(&remote_state->rewrites_push,
 					       name, namelen);
-			add_instead_of(rewrite, xstrdup(value));
+			add_instead_of(rewrite, value);
 		}
 	}
 
-- 
2.55.0-576-g1c3ad6b142