From d0a263ef805244245afd9b709bdd3dc733113a6c Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Sat, 7 Sep 2013 13:41:14 +0200
Subject: [PATCH 06/11] _libssh2_channel_write: client spins on write when window full

When there's no window to "write to", there's no point in waiting for
the socket to become writable since it most likely just will continue to
be.

Patch-by: ncm
Fixes #258

[upstream commit e6c46cc249227de7b7cd136d72eded5dcb3f9381]

Signed-off-by: Kamil Dudka <kdudka@redhat.com>
---
 src/channel.c |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/src/channel.c b/src/channel.c
index 9f2c241..74262d8 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -2039,9 +2039,17 @@ _libssh2_channel_write(LIBSSH2_CHANNEL *channel, int stream_id,
         if((rc < 0) && (rc != LIBSSH2_ERROR_EAGAIN))
             return rc;
 
-        if(channel->local.window_size <= 0)
+        if(channel->local.window_size <= 0) {
             /* there's no room for data so we stop */
+
+            /* Waiting on the socket to be writable would be wrong because we
+             * would be back here immediately, but a readable socket might
+             * herald an incoming window adjustment.
+             */
+            session->socket_block_directions = LIBSSH2_SESSION_BLOCK_INBOUND;
+
             return (rc==LIBSSH2_ERROR_EAGAIN?rc:0);
+        }
 
         channel->write_bufwrite = buflen;
 
-- 
1.7.1