* Add compression option to hosts

1 files changed, 121 insertions, 0 deletions

diff --git a/src/com/trilead/ssh2/compression/Zlib.java b/src/com/trilead/ssh2/compression/Zlib.java
new file mode 100644
index 0000000..c81a719
--- /dev/null
+++ b/src/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;
+			}
+		}
+	}
+}