1 files changed, 130 insertions, 0 deletions
diff --git a/sshlib/src/main/java/com/trilead/ssh2/compression/Zlib.java b/sshlib/src/main/java/com/trilead/ssh2/compression/Zlib.java
new file mode 100644
index 0000000..c1203a3
--- /dev/null
+++ b/sshlib/src/main/java/com/trilead/ssh2/compression/Zlib.java
@@ -0,0 +1,130 @@
+/*
+ * ConnectBot: simple, powerful, open-source SSH client for Android
+ * Copyright 2007 Kenny Root, Jeffrey Sharkey
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+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 DEFAULT_BUF_SIZE = 4096;
+	static private final int LEVEL = 5;
+
+	private ZStream deflate;
+	private byte[] deflate_tmpbuf;
+
+	private ZStream inflate;
+	private byte[] inflate_tmpbuf;
+	private byte[] inflated_buf;
+
+	public Zlib() {
+		deflate = new ZStream();
+		inflate = new ZStream();
+
+		deflate.deflateInit(LEVEL);
+		inflate.inflateInit();
+
+		deflate_tmpbuf = new byte[DEFAULT_BUF_SIZE];
+		inflate_tmpbuf = new byte[DEFAULT_BUF_SIZE];
+		inflated_buf = new byte[DEFAULT_BUF_SIZE];
+	}
+
+	public boolean canCompressPreauth() {
+		return true;
+	}
+
+	public int getBufferSize() {
+		return DEFAULT_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;
+
+		if ((buf.length + 1024) > deflate_tmpbuf.length) {
+			deflate_tmpbuf = new byte[buf.length + 1024];
+		}
+
+		deflate.next_out = deflate_tmpbuf;
+		deflate.next_out_index = 0;
+		deflate.avail_out = output.length;
+
+		if (deflate.deflate(JZlib.Z_PARTIAL_FLUSH) != JZlib.Z_OK) {
+			System.err.println("compress: compression failure");
+		}
+
+		if (deflate.avail_in > 0) {
+			System.err.println("compress: deflated data too large");
+		}
+
+		int outputlen = output.length - deflate.avail_out;
+
+		System.arraycopy(deflate_tmpbuf, 0, output, 0, outputlen);
+
+		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 = DEFAULT_BUF_SIZE;
+			int status = inflate.inflate(JZlib.Z_PARTIAL_FLUSH);
+			switch (status) {
+			case JZlib.Z_OK:
+				if (inflated_buf.length < inflated_end + DEFAULT_BUF_SIZE
+						- inflate.avail_out) {
+					byte[] foo = new byte[inflated_end + DEFAULT_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,
+						DEFAULT_BUF_SIZE - inflate.avail_out);
+				inflated_end += (DEFAULT_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;
+			}
+		}
+	}
+}