gnu: libgit2: Patch bug in HTTP proxy support that shows on 302s.

Fixes guix/guix#87.

* gnu/packages/patches/libgit2-proxy-reconnection.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/version-control.scm (libgit2-1.9)[source]: Use it.

Change-Id: If05b55e616da4d98b3de0e38f6a0d815dd256b92

gnu/local.mk

@@ -1742,6 +1742,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/libgda-skip-postgresql-tests.patch	\
   %D%/packages/patches/libgdata-fix-tests.patch	\
   %D%/packages/patches/libgit2-mtime-0.patch			\
+  %D%/packages/patches/libgit2-proxy-reconnection.patch		\
   %D%/packages/patches/libgit2-uninitialized-proxy-settings.patch	\
   %D%/packages/patches/libgnome-encoding.patch			\
   %D%/packages/patches/libgnomeui-utf8.patch			\

gnu/packages/patches/libgit2-proxy-reconnection.patch

@@ -0,0 +1,18 @@
+Temporary fix for <https://github.com/libgit2/libgit2/issues/7081>.
+Submitted as <https://github.com/libgit2/libgit2/pull/7082>.
+
+diff --git a/src/libgit2/transports/httpclient.c b/src/libgit2/transports/httpclient.c
+index e25e0a73a..ecefbcd3e 100644
+--- a/src/libgit2/transports/httpclient.c
++++ b/src/libgit2/transports/httpclient.c
+@@ -914,6 +914,10 @@ GIT_INLINE(git_http_parser_settings *) http_client_parser_settings(void)
+ 
+ static void reset_parser(git_http_client *client)
+ {
++	/* Force the proxy connection to be closed so a fresh connection is
++	   opened for the next CONNECT request.  */
++	client->proxy_connected = 0;
++
+ 	git_http_parser_init(&client->parser,
+ 	                     GIT_HTTP_PARSER_RESPONSE,
+ 	                     http_client_parser_settings());

gnu/packages/version-control.scm

@@ -1427,6 +1427,9 @@ write native speed custom Git applications in any language with bindings.")
                     (url "https://github.com/libgit2/libgit2")
                     (commit (string-append "v" version))))
               (file-name (git-file-name "libgit2" version))
+              (patches
+               (search-patches "libgit2-uninitialized-proxy-settings.patch"
+                               "libgit2-proxy-reconnection.patch"))
               (sha256
                (base32
                 "06ajn5i5l1209z7x7jxcpw68ph0a6g3q67bmx0jm381rr8cb4zdz"))))))