[PATCH] http.c: don't rewrite the user:passwd string multiple times

[Brandon Casey <bcasey@nvidia.com>]

From: Brandon Casey <drafnel@gmail.com>

Curl requires that we manage any strings that we pass to it as pointers.
So, we should not be overwriting this strbuf after we've passed it to
curl.

Additionally, it is unnecessary since we only prompt for the user name
and password once, so we end up overwriting the strbuf with the same
sequence of characters each time.  This is why in practice it has not
caused any problems for git's use of curl; the internal strbuf char
pointer does not change, and get's overwritten with the same string
each time.

But it's unnecessary and potentially dangerous, so let's avoid it.

Signed-off-by: Brandon Casey <drafnel@gmail.com>
---
 http.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/http.c b/http.c
index 92aba59..6828269 100644
--- a/http.c
+++ b/http.c
@@ -228,8 +228,8 @@ static void init_curl_http_auth(CURL *result)
 #else
 	{
 		static struct strbuf up = STRBUF_INIT;
-		strbuf_reset(&up);
-		strbuf_addf(&up, "%s:%s",
+		if (!up.len)
+			strbuf_addf(&up, "%s:%s",
 			    http_auth.username, http_auth.password);
 		curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 	}
-- 
1.8.3.1.440.gc2bf105