[PATCH] transport: do not allow to push over git:// protocol

["Nguyễn Thái Ngọc Duy" <pclouds@gmail.com>]

This protocol has never been designed for pushing. Attempts to push
over git:// usually result in

  fatal: The remote end hung up unexpectedly

That message does not really point out the reason. With this patch, we get

  error: this protocol does not support pushing
  error: failed to push some refs to 'git://some-host.com/my/repo'

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 I wanted to advise using remote.*.pushurl too, more friendly. But then I
 had to detect if url comes from command line or config, and I gave up.

 transport.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/transport.c b/transport.c
index fa279d5..b109145 100644
--- a/transport.c
+++ b/transport.c
@@ -933,7 +933,8 @@ struct transport *transport_get(struct remote *remote, const char *url)
 		ret->set_option = NULL;
 		ret->get_refs_list = get_refs_via_connect;
 		ret->fetch = fetch_refs_via_pack;
-		ret->push_refs = git_transport_push;
+		if (prefixcmp(url, "git://"))
+			ret->push_refs = git_transport_push;
 		ret->connect = connect_git;
 		ret->disconnect = disconnect_git;
 		ret->smart_options = &(data->options);
@@ -1075,6 +1076,8 @@ int transport_push(struct transport *transport,
 
 		return ret;
 	}
+	else
+		return error("this protocol does not support pushing");
 	return 1;
 }
 
-- 
1.7.3.1.256.g2539c.dirty