From ba2f21eb85bb9c0f22c291e576560981448bb185 Mon Sep 17 00:00:00 2001
From: Sara Golemon <pollita@libssh2.org>
Date: Fri, 6 May 2005 18:30:43 +0000
Subject: [PATCH] More fixes for channel_write()

---
 README        |  5 +++++
 src/channel.c | 18 ++++++++++++------
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/README b/README
index bc1498b..0d88c87 100644
--- a/README
+++ b/README
@@ -1,6 +1,11 @@
 libssh2 - SSH2 library
 ======================
 
+Version 0.10
+------------
+
+  (Re)Fixed channel_write() to provide an opportunity for window space to become available again.
+
 Version 0.9
 -----------
 
diff --git a/src/channel.c b/src/channel.c
index 7100399..5182599 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -861,12 +861,9 @@ LIBSSH2_API int libssh2_channel_write_ex(LIBSSH2_CHANNEL *channel, int stream_id
 		libssh2_error(session, LIBSSH2_ERROR_CHANNEL_EOF_SENT, "EOF has already been sight, data might be ignored", 0);
 	}
 
-	if (channel->blocking && (channel->local.window_size <= 0)) {
-		/* twiddle our thumbs until there's window space available */
-		if (libssh2_packet_read(session, 1) < 0) {
-			/* Error occured, disconnect? */
-			return -1;
-		}
+	if (!channel->blocking && (channel->local.window_size <= 0)) {
+		/* Can't write anything */
+		return 0;
 	}
 
 	packet_len = buflen + (stream_id ? 13 : 9); /* packet_type(1) + channelno(4) [ + streamid(4) ] + buflen(4) */
@@ -886,6 +883,15 @@ LIBSSH2_API int libssh2_channel_write_ex(LIBSSH2_CHANNEL *channel, int stream_id
 			libssh2_htonu32(s, stream_id);						s += 4;
 		}
 
+		/* twiddle our thumbs until there's window space available */
+		while (channel->local.window_size <= 0) {
+			/* Don't worry -- This is never hit unless it's a blocking channel anyway */
+			if (libssh2_packet_read(session, 1) < 0) {
+				/* Error occured, disconnect? */
+				return -1;
+			}
+		}
+
 		/* Don't exceed the remote end's limits */
 		/* REMEMBER local means local as the SOURCE of the data */
 		if (bufwrite > channel->local.window_size) {