Merge branch 'jk/http-auth-redirects'

Handle the case where http transport gets redirected during the
authorization request better.

* jk/http-auth-redirects:
  http.c: Spell the null pointer as NULL
  remote-curl: rewrite base url from info/refs redirects
  remote-curl: store url as a strbuf
  remote-curl: make refs_url a strbuf
  http: update base URLs when we see redirects
  http: provide effective url to callers
  http: hoist credential request out of handle_curl_result
  http: refactor options to http_get_*
  http_request: factor out curlinfo_strbuf
  http_get_file: style fixes

t/t5551-http-fetch.sh

@@ -113,6 +113,10 @@ test_expect_success 'follow redirects (302)' '
 	git clone $HTTPD_URL/smart-redir-temp/repo.git --quiet repo-t
 '
 
+test_expect_success 'redirects re-root further requests' '
+	git clone $HTTPD_URL/smart-redir-limited/repo.git repo-redir-limited
+'
+
 test_expect_success 'clone from password-protected repository' '
 	echo two >expect &&
 	set_askpass user@host &&
@@ -146,6 +150,13 @@ test_expect_success 'no-op half-auth fetch does not require a password' '
 	expect_askpass none
 '
 
+test_expect_success 'redirects send auth to new location' '
+	set_askpass user@host &&
+	git -c credential.useHttpPath=true \
+	  clone $HTTPD_URL/smart-redir-auth/repo.git repo-redir-auth &&
+	expect_askpass both user@host auth/smart/repo.git
+'
+
 test_expect_success 'disable dumb http on server' '
 	git --git-dir="$HTTPD_DOCUMENT_ROOT_PATH/repo.git" \
 		config http.getanyfile false