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

   1 /*
   2  * Copyright (C) 2008, Robin Rosenberg <robin.rosenberg@dewire.com>
   3  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
   4  *
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or
   8  * without modification, are permitted provided that the following
   9  * conditions are met:
  10  *
  11  * - Redistributions of source code must retain the above copyright
  12  *   notice, this list of conditions and the following disclaimer.
  13  *
  14  * - Redistributions in binary form must reproduce the above
  15  *   copyright notice, this list of conditions and the following
  16  *   disclaimer in the documentation and/or other materials provided
  17  *   with the distribution.
  18  *
  19  * - Neither the name of the Git Development Community nor the
  20  *   names of its contributors may be used to endorse or promote
  21  *   products derived from this software without specific prior
  22  *   written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  25  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  26  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  29  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  32  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  33  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  34  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  36  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 package org.spearce.jgit.transport;
  40
  41 import java.io.IOException;
  42 import java.io.OutputStream;
  43
  44 import org.spearce.jgit.lib.Constants;
  45
  46 class PacketLineOut {
  47         private final OutputStream out;
  48
  49         private final byte[] lenbuffer;
  50
  51         PacketLineOut(final OutputStream i) {
  52                 out = i;
  53                 lenbuffer = new byte[5];
  54         }
  55
  56         void writeString(final String s) throws IOException {
  57                 writePacket(Constants.encode(s));
  58         }
  59
  60         void writePacket(final byte[] packet) throws IOException {
  61                 formatLength(packet.length + 4);
  62                 out.write(lenbuffer, 0, 4);
  63                 out.write(packet);
  64         }
  65
  66         void writeChannelPacket(final int channel, final byte[] buf, int off,
  67                         int len) throws IOException {
  68                 formatLength(len + 5);
  69                 lenbuffer[4] = (byte) channel;
  70                 out.write(lenbuffer, 0, 5);
  71                 out.write(buf, off, len);
  72         }
  73
  74         void end() throws IOException {
  75                 formatLength(0);
  76                 out.write(lenbuffer, 0, 4);
  77                 flush();
  78         }
  79
  80         void flush() throws IOException {
  81                 out.flush();
  82         }
  83
  84         private static final byte[] hexchar = { '0', '1', '2', '3', '4', '5', '6',
  85                         '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
  86
  87         private void formatLength(int w) {
  88                 int o = 3;
  89                 while (o >= 0 && w != 0) {
  90                         lenbuffer[o--] = hexchar[w & 0xf];
  91                         w >>>= 4;
  92                 }
  93                 while (o >= 0)
  94                         lenbuffer[o--] = '0';
  95         }
  96 }