public int getChannelData()

in cvs/trilead-ssh2-build213/src/com/trilead/ssh2/channel/ChannelManager.java [938:1058]
84 lines of code
19 McCabe index (conditional complexity)

	public int getChannelData(Channel c, boolean extended, byte[] target, int off, int len) throws IOException
	{
		int copylen = 0;
		int increment = 0;
		int remoteID = 0;
		int localID = 0;

		synchronized (c)
		{
			int stdoutAvail = 0;
			int stderrAvail = 0;

			while (true)
			{
				/*
				 * Data available? We have to return remaining data even if the
				 * channel is already closed.
				 */

				stdoutAvail = c.stdoutWritepos - c.stdoutReadpos;
				stderrAvail = c.stderrWritepos - c.stderrReadpos;

				if ((!extended) && (stdoutAvail != 0))
					break;

				if ((extended) && (stderrAvail != 0))
					break;

				/* Do not wait if more data will never arrive (EOF or CLOSED) */

				if ((c.EOF) || (c.state != Channel.STATE_OPEN))
					return -1;

				try
				{
					c.wait();
				}
				catch (InterruptedException ignore)
				{
				}
			}

			/* OK, there is some data. Return it. */

			if (!extended)
			{
				copylen = (stdoutAvail > len) ? len : stdoutAvail;
				System.arraycopy(c.stdoutBuffer, c.stdoutReadpos, target, off, copylen);
				c.stdoutReadpos += copylen;

				if (c.stdoutReadpos != c.stdoutWritepos)

					System.arraycopy(c.stdoutBuffer, c.stdoutReadpos, c.stdoutBuffer, 0, c.stdoutWritepos
							- c.stdoutReadpos);

				c.stdoutWritepos -= c.stdoutReadpos;
				c.stdoutReadpos = 0;
			}
			else
			{
				copylen = (stderrAvail > len) ? len : stderrAvail;
				System.arraycopy(c.stderrBuffer, c.stderrReadpos, target, off, copylen);
				c.stderrReadpos += copylen;

				if (c.stderrReadpos != c.stderrWritepos)

					System.arraycopy(c.stderrBuffer, c.stderrReadpos, c.stderrBuffer, 0, c.stderrWritepos
							- c.stderrReadpos);

				c.stderrWritepos -= c.stderrReadpos;
				c.stderrReadpos = 0;
			}

			if (c.state != Channel.STATE_OPEN)
				return copylen;

			if (c.localWindow < ((Channel.CHANNEL_BUFFER_SIZE + 1) / 2))
			{
				int minFreeSpace = Math.min(Channel.CHANNEL_BUFFER_SIZE - c.stdoutWritepos, Channel.CHANNEL_BUFFER_SIZE
						- c.stderrWritepos);

				increment = minFreeSpace - c.localWindow;
				c.localWindow = minFreeSpace;
			}

			remoteID = c.remoteID; /* read while holding the lock */
			localID = c.localID; /* read while holding the lock */
		}

		/*
		 * If a consumer reads stdout and stdin in parallel, we may end up with
		 * sending two msgWindowAdjust messages. Luckily, it
		 * does not matter in which order they arrive at the server.
		 */

		if (increment > 0)
		{
			if (log.isEnabled())
				log.log(80, "Sending SSH_MSG_CHANNEL_WINDOW_ADJUST (channel " + localID + ", " + increment + ")");

			synchronized (c.channelSendLock)
			{
				byte[] msg = c.msgWindowAdjust;

				msg[0] = Packets.SSH_MSG_CHANNEL_WINDOW_ADJUST;
				msg[1] = (byte) (remoteID >> 24);
				msg[2] = (byte) (remoteID >> 16);
				msg[3] = (byte) (remoteID >> 8);
				msg[4] = (byte) (remoteID);
				msg[5] = (byte) (increment >> 24);
				msg[6] = (byte) (increment >> 16);
				msg[7] = (byte) (increment >> 8);
				msg[8] = (byte) (increment);

				if (c.closeMessageSent == false)
					tm.sendMessage(msg);
			}
		}

		return copylen;
	}