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

   1 /*
   2  * Copyright (C) 2008, Google Inc.
   3  * Copyright (C) 2008-2009, Robin Rosenberg <robin.rosenberg@dewire.com>
   4  * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
   5  * and other copyright owners as documented in the project's IP log.
   6  *
   7  * This program and the accompanying materials are made available
   8  * under the terms of the Eclipse Distribution License v1.0 which
   9  * accompanies this distribution, is reproduced below, and is
  10  * available at http://www.eclipse.org/org/documents/edl-v10.php
  11  *
  12  * All rights reserved.
  13  *
  14  * Redistribution and use in source and binary forms, with or
  15  * without modification, are permitted provided that the following
  16  * conditions are met:
  17  *
  18  * - Redistributions of source code must retain the above copyright
  19  *   notice, this list of conditions and the following disclaimer.
  20  *
  21  * - Redistributions in binary form must reproduce the above
  22  *   copyright notice, this list of conditions and the following
  23  *   disclaimer in the documentation and/or other materials provided
  24  *   with the distribution.
  25  *
  26  * - Neither the name of the Eclipse Foundation, Inc. nor the
  27  *   names of its contributors may be used to endorse or promote
  28  *   products derived from this software without specific prior
  29  *   written permission.
  30  *
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  32  * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  33  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  34  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  35  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  36  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  37  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  38  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  39  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  40  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  41  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  42  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  43  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  44  */
  45
  46 package org.eclipse.jgit.transport;
  47
  48 import java.io.IOException;
  49 import java.io.OutputStream;
  50
  51 import org.eclipse.jgit.lib.Constants;
  52
  53 class PacketLineOut {
  54         private final OutputStream out;
  55
  56         private final byte[] lenbuffer;
  57
  58         PacketLineOut(final OutputStream i) {
  59                 out = i;
  60                 lenbuffer = new byte[5];
  61         }
  62
  63         void writeString(final String s) throws IOException {
  64                 writePacket(Constants.encode(s));
  65         }
  66
  67         void writePacket(final byte[] packet) throws IOException {
  68                 formatLength(packet.length + 4);
  69                 out.write(lenbuffer, 0, 4);
  70                 out.write(packet);
  71         }
  72
  73         void writeChannelPacket(final int channel, final byte[] buf, int off,
  74                         int len) throws IOException {
  75                 formatLength(len + 5);
  76                 lenbuffer[4] = (byte) channel;
  77                 out.write(lenbuffer, 0, 5);
  78                 out.write(buf, off, len);
  79         }
  80
  81         void end() throws IOException {
  82                 formatLength(0);
  83                 out.write(lenbuffer, 0, 4);
  84                 flush();
  85         }
  86
  87         void flush() throws IOException {
  88                 out.flush();
  89         }
  90
  91         private static final byte[] hexchar = { '0', '1', '2', '3', '4', '5', '6',
  92                         '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
  93
  94         private void formatLength(int w) {
  95                 int o = 3;
  96                 while (o >= 0 && w != 0) {
  97                         lenbuffer[o--] = hexchar[w & 0xf];
  98                         w >>>= 4;
  99                 }
 100                 while (o >= 0)
 101                         lenbuffer[o--] = '0';
 102         }
 103 }