Fix hang when fetching over SSH

JSch may hang or abort with the timeout if JGit connects before
its obtained the streams.  Instead defer the connect() call until
after the streams have been configured.

Bug: 312383
Change-Id: I7c3a687ba4cb69a41a85e2b60d381d42b9090e3f
Reported-by: Dmitry Neverov <dmitry.neverov@gmail.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportGitSsh.java

@@ -147,17 +147,25 @@ public class TransportGitSsh extends SshTransport implements PackTransport {
 	ChannelExec exec(final String exe) throws TransportException {
 		initSession();
 
-		final int tms = getTimeout() > 0 ? getTimeout() * 1000 : 0;
 		try {
 			final ChannelExec channel = (ChannelExec) sock.openChannel("exec");
 			channel.setCommand(commandFor(exe));
-			channel.connect(tms);
 			return channel;
 		} catch (JSchException je) {
 			throw new TransportException(uri, je.getMessage(), je);
 		}
 	}
 
+	private void connect(ChannelExec channel) throws TransportException {
+		try {
+			channel.connect(getTimeout() > 0 ? getTimeout() * 1000 : 0);
+			if (!channel.isConnected())
+				throw new TransportException(uri, "connection failed");
+		} catch (JSchException e) {
+			throw new TransportException(uri, e.getMessage(), e);
+		}
+	}
+
 	void checkExecFailure(int status, String exe, String why)
 			throws TransportException {
 		if (status == 127) {
@@ -235,14 +243,13 @@ public class TransportGitSsh extends SshTransport implements PackTransport {
 				setMessageWriter(msg);
 
 				channel = exec(getOptionUploadPack());
-				if (!channel.isConnected())
-					throw new TransportException(uri, "connection failed");
 
 				final InputStream upErr = channel.getErrStream();
 				errorThread = new StreamCopyThread(upErr, msg.getRawStream());
 				errorThread.start();
 
 				init(channel.getInputStream(), outputStream(channel));
+				connect(channel);
 
 			} catch (TransportException err) {
 				close();
@@ -304,14 +311,13 @@ public class TransportGitSsh extends SshTransport implements PackTransport {
 				setMessageWriter(msg);
 
 				channel = exec(getOptionReceivePack());
-				if (!channel.isConnected())
-					throw new TransportException(uri, "connection failed");
 
 				final InputStream rpErr = channel.getErrStream();
 				errorThread = new StreamCopyThread(rpErr, msg.getRawStream());
 				errorThread.start();
 
 				init(channel.getInputStream(), outputStream(channel));
+				connect(channel);
 
 			} catch (TransportException err) {
 				close();