mirror of
https://github.com/moparisthebest/k-9
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
Implement DEFLATE compression for IMAP communication, enabled by default. User can disable compression for Wi-Fi, Mobile, or Other networks, if it causes problems or if uncompressed communication is faster, which is possible on Wi-Fi and wired networks, especially. "Other" is to allow for the Android platform to introduce new networking types without having to immediately change K-9 Mail. However, as those arise, new network types should be added as explicit types in K-9 Mail.
196 lines
6.2 KiB
Java
196 lines
6.2 KiB
Java
/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
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/*
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Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are met:
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1. Redistributions of source code must retain the above copyright notice,
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this list of conditions and the following disclaimer.
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2. Redistributions in binary form must reproduce the above copyright
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notice, this list of conditions and the following disclaimer in
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the documentation and/or other materials provided with the distribution.
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3. The names of the authors may not be used to endorse or promote products
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derived from this software without specific prior written permission.
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THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
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INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
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INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
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INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
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OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
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EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* This program is based on zlib-1.1.3, so all credit should go authors
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* Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
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* and contributors of zlib.
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*/
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package com.jcraft.jzlib;
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final public class ZStream{
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static final private int MAX_WBITS=15; // 32K LZ77 window
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static final private int DEF_WBITS=MAX_WBITS;
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static final private int Z_STREAM_ERROR=-2;
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public byte[] next_in; // next input byte
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public int next_in_index;
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public int avail_in; // number of bytes available at next_in
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public long total_in; // total nb of input bytes read so far
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public byte[] next_out; // next output byte should be put there
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public int next_out_index;
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public int avail_out; // remaining free space at next_out
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public long total_out; // total nb of bytes output so far
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public String msg;
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Deflate dstate;
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Inflate istate;
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int data_type; // best guess about the data type: ascii or binary
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public long adler;
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Adler32 _adler=new Adler32();
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public int inflateInit(){
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return inflateInit(DEF_WBITS);
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}
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public int inflateInit(boolean nowrap){
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return inflateInit(DEF_WBITS, nowrap);
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}
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public int inflateInit(int w){
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return inflateInit(w, false);
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}
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public int inflateInit(int w, boolean nowrap){
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istate=new Inflate();
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return istate.inflateInit(this, nowrap?-w:w);
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}
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public int inflate(int f){
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if(istate==null) return Z_STREAM_ERROR;
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return istate.inflate(this, f);
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}
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public int inflateEnd(){
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if(istate==null) return Z_STREAM_ERROR;
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int ret=istate.inflateEnd(this);
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istate = null;
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return ret;
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}
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public int inflateSync(){
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if(istate == null)
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return Z_STREAM_ERROR;
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return istate.inflateSync(this);
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}
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public int inflateSetDictionary(byte[] dictionary, int dictLength){
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if(istate == null)
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return Z_STREAM_ERROR;
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return istate.inflateSetDictionary(this, dictionary, dictLength);
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}
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public int deflateInit(int level){
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return deflateInit(level, MAX_WBITS);
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}
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public int deflateInit(int level, boolean nowrap){
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return deflateInit(level, MAX_WBITS, nowrap);
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}
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public int deflateInit(int level, int bits){
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return deflateInit(level, bits, false);
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}
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public int deflateInit(int level, int bits, boolean nowrap){
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dstate=new Deflate();
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return dstate.deflateInit(this, level, nowrap?-bits:bits);
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}
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public int deflate(int flush){
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if(dstate==null){
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return Z_STREAM_ERROR;
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}
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return dstate.deflate(this, flush);
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}
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public int deflateEnd(){
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if(dstate==null) return Z_STREAM_ERROR;
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int ret=dstate.deflateEnd();
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dstate=null;
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return ret;
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}
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public int deflateParams(int level, int strategy){
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if(dstate==null) return Z_STREAM_ERROR;
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return dstate.deflateParams(this, level, strategy);
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}
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public int deflateSetDictionary (byte[] dictionary, int dictLength){
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if(dstate == null)
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return Z_STREAM_ERROR;
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return dstate.deflateSetDictionary(this, dictionary, dictLength);
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}
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// Flush as much pending output as possible. All deflate() output goes
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// through this function so some applications may wish to modify it
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// to avoid allocating a large strm->next_out buffer and copying into it.
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// (See also read_buf()).
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void flush_pending(){
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int len=dstate.pending;
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if(len>avail_out) len=avail_out;
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if(len==0) return;
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if(dstate.pending_buf.length<=dstate.pending_out ||
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next_out.length<=next_out_index ||
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dstate.pending_buf.length<(dstate.pending_out+len) ||
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next_out.length<(next_out_index+len)){
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System.out.println(dstate.pending_buf.length+", "+dstate.pending_out+
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", "+next_out.length+", "+next_out_index+", "+len);
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System.out.println("avail_out="+avail_out);
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}
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System.arraycopy(dstate.pending_buf, dstate.pending_out,
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next_out, next_out_index, len);
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next_out_index+=len;
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dstate.pending_out+=len;
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total_out+=len;
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avail_out-=len;
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dstate.pending-=len;
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if(dstate.pending==0){
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dstate.pending_out=0;
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}
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}
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// Read a new buffer from the current input stream, update the adler32
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// and total number of bytes read. All deflate() input goes through
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// this function so some applications may wish to modify it to avoid
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// allocating a large strm->next_in buffer and copying from it.
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// (See also flush_pending()).
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int read_buf(byte[] buf, int start, int size) {
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int len=avail_in;
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if(len>size) len=size;
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if(len==0) return 0;
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avail_in-=len;
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if(dstate.noheader==0) {
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adler=_adler.adler32(adler, next_in, next_in_index, len);
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}
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System.arraycopy(next_in, next_in_index, buf, start, len);
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next_in_index += len;
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total_in += len;
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return len;
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}
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public void free(){
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next_in=null;
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next_out=null;
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msg=null;
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_adler=null;
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}
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}
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