diff options
Diffstat (limited to 'lib/src/main/java/com/trilead/ssh2/compression')
3 files changed, 247 insertions, 0 deletions
diff --git a/lib/src/main/java/com/trilead/ssh2/compression/CompressionFactory.java b/lib/src/main/java/com/trilead/ssh2/compression/CompressionFactory.java new file mode 100644 index 0000000..30b3d21 --- /dev/null +++ b/lib/src/main/java/com/trilead/ssh2/compression/CompressionFactory.java @@ -0,0 +1,96 @@ +/* + ConnectBot: simple, powerful, open-source SSH client for Android + Copyright (C) 2007-2008 Kenny Root, Jeffrey Sharkey + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ +package com.trilead.ssh2.compression; + +import java.util.Vector; + +/** + * @author Kenny Root + * + */ +public class CompressionFactory { + static class CompressorEntry + { + String type; + String compressorClass; + + public CompressorEntry(String type, String compressorClass) + { + this.type = type; + this.compressorClass = compressorClass; + } + } + + static Vector<CompressorEntry> compressors = new Vector<CompressorEntry>(); + + static + { + /* Higher Priority First */ + + compressors.addElement(new CompressorEntry("zlib", "com.trilead.ssh2.compression.Zlib")); + compressors.addElement(new CompressorEntry("zlib@openssh.com", "com.trilead.ssh2.compression.Zlib")); + compressors.addElement(new CompressorEntry("none", "")); + } + + public static String[] getDefaultCompressorList() + { + String list[] = new String[compressors.size()]; + for (int i = 0; i < compressors.size(); i++) + { + CompressorEntry ce = compressors.elementAt(i); + list[i] = new String(ce.type); + } + return list; + } + + public static void checkCompressorList(String[] compressorCandidates) + { + for (int i = 0; i < compressorCandidates.length; i++) + getEntry(compressorCandidates[i]); + } + + public static ICompressor createCompressor(String type) + { + try + { + CompressorEntry ce = getEntry(type); + if ("".equals(ce.compressorClass)) + return null; + + Class<?> cc = Class.forName(ce.compressorClass); + ICompressor cmp = (ICompressor) cc.newInstance(); + + return cmp; + } + catch (Exception e) + { + throw new IllegalArgumentException("Cannot instantiate " + type); + } + } + + private static CompressorEntry getEntry(String type) + { + for (int i = 0; i < compressors.size(); i++) + { + CompressorEntry ce = compressors.elementAt(i); + if (ce.type.equals(type)) + return ce; + } + throw new IllegalArgumentException("Unkown algorithm " + type); + } +} diff --git a/lib/src/main/java/com/trilead/ssh2/compression/ICompressor.java b/lib/src/main/java/com/trilead/ssh2/compression/ICompressor.java new file mode 100644 index 0000000..a71d31b --- /dev/null +++ b/lib/src/main/java/com/trilead/ssh2/compression/ICompressor.java @@ -0,0 +1,30 @@ +/* + ConnectBot: simple, powerful, open-source SSH client for Android + Copyright (C) 2007-2008 Kenny Root, Jeffrey Sharkey + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +package com.trilead.ssh2.compression; + +/** + * @author Kenny Root + * + */ +public interface ICompressor { + int getBufferSize(); + + int compress(byte[] buf, int start, int len, byte[] output); + + byte[] uncompress(byte[] buf, int start, int[] len); +} diff --git a/lib/src/main/java/com/trilead/ssh2/compression/Zlib.java b/lib/src/main/java/com/trilead/ssh2/compression/Zlib.java new file mode 100644 index 0000000..c81a719 --- /dev/null +++ b/lib/src/main/java/com/trilead/ssh2/compression/Zlib.java @@ -0,0 +1,121 @@ +/* + ConnectBot: simple, powerful, open-source SSH client for Android + Copyright (C) 2007-2008 Kenny Root, Jeffrey Sharkey + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +package com.trilead.ssh2.compression; + +import com.jcraft.jzlib.JZlib; +import com.jcraft.jzlib.ZStream; + +/** + * @author Kenny Root + * + */ +public class Zlib implements ICompressor { + static private final int BUF_SIZE = 4096; + static private final int LEVEL = 5; + + private ZStream deflate; + private byte[] deflate_tmpbuf = new byte[BUF_SIZE]; + + private ZStream inflate; + private byte[] inflate_tmpbuf = new byte[BUF_SIZE]; + private byte[] inflated_buf; + + public Zlib() { + deflate = new ZStream(); + inflate = new ZStream(); + + deflate.deflateInit(LEVEL); + inflate.inflateInit(); + inflated_buf = new byte[BUF_SIZE]; + } + + public int getBufferSize() { + return BUF_SIZE; + } + + public int compress(byte[] buf, int start, int len, byte[] output) { + deflate.next_in = buf; + deflate.next_in_index = start; + deflate.avail_in = len - start; + + int status; + int outputlen = start; + + do { + deflate.next_out = deflate_tmpbuf; + deflate.next_out_index = 0; + deflate.avail_out = BUF_SIZE; + status = deflate.deflate(JZlib.Z_PARTIAL_FLUSH); + switch (status) { + case JZlib.Z_OK: + System.arraycopy(deflate_tmpbuf, 0, output, outputlen, BUF_SIZE + - deflate.avail_out); + outputlen += (BUF_SIZE - deflate.avail_out); + break; + default: + System.err.println("compress: deflate returnd " + status); + } + } while (deflate.avail_out == 0); + return outputlen; + } + + public byte[] uncompress(byte[] buffer, int start, int[] length) { + int inflated_end = 0; + + inflate.next_in = buffer; + inflate.next_in_index = start; + inflate.avail_in = length[0]; + + while (true) { + inflate.next_out = inflate_tmpbuf; + inflate.next_out_index = 0; + inflate.avail_out = BUF_SIZE; + int status = inflate.inflate(JZlib.Z_PARTIAL_FLUSH); + switch (status) { + case JZlib.Z_OK: + if (inflated_buf.length < inflated_end + BUF_SIZE + - inflate.avail_out) { + byte[] foo = new byte[inflated_end + BUF_SIZE + - inflate.avail_out]; + System.arraycopy(inflated_buf, 0, foo, 0, inflated_end); + inflated_buf = foo; + } + System.arraycopy(inflate_tmpbuf, 0, inflated_buf, inflated_end, + BUF_SIZE - inflate.avail_out); + inflated_end += (BUF_SIZE - inflate.avail_out); + length[0] = inflated_end; + break; + case JZlib.Z_BUF_ERROR: + if (inflated_end > buffer.length - start) { + byte[] foo = new byte[inflated_end + start]; + System.arraycopy(buffer, 0, foo, 0, start); + System.arraycopy(inflated_buf, 0, foo, start, inflated_end); + buffer = foo; + } else { + System.arraycopy(inflated_buf, 0, buffer, start, + inflated_end); + } + length[0] = inflated_end; + return buffer; + default: + System.err.println("uncompress: inflate returnd " + status); + return null; + } + } + } +} |