org.spearce.jgit/src/org/spearce/jgit/transport/SideBandOutputStream.java

   1 /*
   2  * Copyright (C) 2008, Google Inc.
   3  *
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or
   7  * without modification, are permitted provided that the following
   8  * conditions are met:
   9  *
  10  * - Redistributions of source code must retain the above copyright
  11  *   notice, this list of conditions and the following disclaimer.
  12  *
  13  * - Redistributions in binary form must reproduce the above
  14  *   copyright notice, this list of conditions and the following
  15  *   disclaimer in the documentation and/or other materials provided
  16  *   with the distribution.
  17  *
  18  * - Neither the name of the Git Development Community nor the
  19  *   names of its contributors may be used to endorse or promote
  20  *   products derived from this software without specific prior
  21  *   written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  24  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  25  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  29  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  31  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  32  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  33  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  35  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  */
  37
  38 package org.spearce.jgit.transport;
  39
  40 import java.io.IOException;
  41 import java.io.OutputStream;
  42
  43 /**
  44  * Multiplexes data and progress messages
  45  * <p>
  46  * To correctly use this class you must wrap it in a BufferedOutputStream with a
  47  * buffer size no larger than either {@link #SMALL_BUF} or {@link #MAX_BUF},
  48  * minus {@link #HDR_SIZE}.
  49  */
  50 class SideBandOutputStream extends OutputStream {
  51         static final int CH_DATA = SideBandInputStream.CH_DATA;
  52
  53         static final int CH_PROGRESS = SideBandInputStream.CH_PROGRESS;
  54
  55         static final int CH_ERROR = SideBandInputStream.CH_ERROR;
  56
  57         static final int SMALL_BUF = 1000;
  58
  59         static final int MAX_BUF = 65520;
  60
  61         static final int HDR_SIZE = 5;
  62
  63         private final int channel;
  64
  65         private final PacketLineOut pckOut;
  66
  67         private byte[] singleByteBuffer;
  68
  69         SideBandOutputStream(final int chan, final PacketLineOut out) {
  70                 channel = chan;
  71                 pckOut = out;
  72         }
  73
  74         @Override
  75         public void flush() throws IOException {
  76                 if (channel != CH_DATA)
  77                         pckOut.flush();
  78         }
  79
  80         @Override
  81         public void write(final byte[] b, final int off, final int len)
  82                         throws IOException {
  83                 pckOut.writeChannelPacket(channel, b, off, len);
  84         }
  85
  86         @Override
  87         public void write(final int b) throws IOException {
  88                 if (singleByteBuffer == null)
  89                         singleByteBuffer = new byte[1];
  90                 singleByteBuffer[0] = (byte) b;
  91                 write(singleByteBuffer);
  92         }
  93 }