jaroslav@694: /* -*-mode:java; c-basic-offset:2; -*- */
jaroslav@694: /*
jaroslav@694: Copyright (c) 2000-2011 ymnk, JCraft,Inc. All rights reserved.
jaroslav@694: 
jaroslav@694: Redistribution and use in source and binary forms, with or without
jaroslav@694: modification, are permitted provided that the following conditions are met:
jaroslav@694: 
jaroslav@694:   1. Redistributions of source code must retain the above copyright notice,
jaroslav@694:      this list of conditions and the following disclaimer.
jaroslav@694: 
jaroslav@694:   2. Redistributions in binary form must reproduce the above copyright 
jaroslav@694:      notice, this list of conditions and the following disclaimer in 
jaroslav@694:      the documentation and/or other materials provided with the distribution.
jaroslav@694: 
jaroslav@694:   3. The names of the authors may not be used to endorse or promote products
jaroslav@694:      derived from this software without specific prior written permission.
jaroslav@694: 
jaroslav@694: THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
jaroslav@694: INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
jaroslav@694: FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
jaroslav@694: INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
jaroslav@694: INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
jaroslav@694: LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
jaroslav@694: OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
jaroslav@694: LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
jaroslav@694: NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
jaroslav@694: EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
jaroslav@694:  */
jaroslav@694: /*
jaroslav@694:  * This program is based on zlib-1.1.3, so all credit should go authors
jaroslav@694:  * Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
jaroslav@694:  * and contributors of zlib.
jaroslav@694:  */
jaroslav@694: 
jaroslav@694: package org.apidesign.bck2brwsr.emul.zip;
jaroslav@694: 
jaroslav@694: import org.apidesign.bck2brwsr.emul.lang.System;
jaroslav@694: 
jaroslav@694: final class Inflate{
jaroslav@694:   
jaroslav@694:   static final private int MAX_WBITS=15; // 32K LZ77 window
jaroslav@694: 
jaroslav@694:   // preset dictionary flag in zlib header
jaroslav@694:   static final private int PRESET_DICT=0x20;
jaroslav@694: 
jaroslav@694:   static final int Z_NO_FLUSH=0;
jaroslav@694:   static final int Z_PARTIAL_FLUSH=1;
jaroslav@694:   static final int Z_SYNC_FLUSH=2;
jaroslav@694:   static final int Z_FULL_FLUSH=3;
jaroslav@694:   static final int Z_FINISH=4;
jaroslav@694: 
jaroslav@694:   static final private int Z_DEFLATED=8;
jaroslav@694: 
jaroslav@694:   static final private int Z_OK=0;
jaroslav@694:   static final private int Z_STREAM_END=1;
jaroslav@694:   static final private int Z_NEED_DICT=2;
jaroslav@694:   static final private int Z_ERRNO=-1;
jaroslav@694:   static final private int Z_STREAM_ERROR=-2;
jaroslav@694:   static final private int Z_DATA_ERROR=-3;
jaroslav@694:   static final private int Z_MEM_ERROR=-4;
jaroslav@694:   static final private int Z_BUF_ERROR=-5;
jaroslav@694:   static final private int Z_VERSION_ERROR=-6;
jaroslav@694: 
jaroslav@694:   static final private int METHOD=0;   // waiting for method byte
jaroslav@694:   static final private int FLAG=1;     // waiting for flag byte
jaroslav@694:   static final private int DICT4=2;    // four dictionary check bytes to go
jaroslav@694:   static final private int DICT3=3;    // three dictionary check bytes to go
jaroslav@694:   static final private int DICT2=4;    // two dictionary check bytes to go
jaroslav@694:   static final private int DICT1=5;    // one dictionary check byte to go
jaroslav@694:   static final int DICT0=6;    // waiting for inflateSetDictionary
jaroslav@694:   static final private int BLOCKS=7;   // decompressing blocks
jaroslav@694:   static final private int CHECK4=8;   // four check bytes to go
jaroslav@694:   static final private int CHECK3=9;   // three check bytes to go
jaroslav@694:   static final private int CHECK2=10;  // two check bytes to go
jaroslav@694:   static final private int CHECK1=11;  // one check byte to go
jaroslav@694:   static final private int DONE=12;    // finished check, done
jaroslav@694:   static final private int BAD=13;     // got an error--stay here
jaroslav@694: 
jaroslav@694:   static final private int HEAD=14;
jaroslav@694:   static final private int LENGTH=15;
jaroslav@694:   static final private int TIME=16;
jaroslav@694:   static final private int OS=17;
jaroslav@694:   static final private int EXLEN=18;
jaroslav@694:   static final private int EXTRA=19;
jaroslav@694:   static final private int NAME=20;
jaroslav@694:   static final private int COMMENT=21;
jaroslav@694:   static final private int HCRC=22;
jaroslav@694:   static final private int FLAGS=23;
jaroslav@694: 
jaroslav@694:   int mode;                            // current inflate mode
jaroslav@694: 
jaroslav@694:   // mode dependent information
jaroslav@694:   int method;        // if FLAGS, method byte
jaroslav@694: 
jaroslav@694:   // if CHECK, check values to compare
jaroslav@694:   long was = -1;           // computed check value
jaroslav@694:   long need;               // stream check value
jaroslav@694: 
jaroslav@694:   // if BAD, inflateSync's marker bytes count
jaroslav@694:   int marker;
jaroslav@694: 
jaroslav@694:   // mode independent information
jaroslav@694:   int  wrap;          // flag for no wrapper
jaroslav@694:   int wbits;            // log2(window size)  (8..15, defaults to 15)
jaroslav@694: 
jaroslav@694:   InfBlocks blocks;     // current inflate_blocks state
jaroslav@694: 
jaroslav@694:   private final ZStream z;
jaroslav@694: 
jaroslav@694:   private int flags; 
jaroslav@694: 
jaroslav@694:   private int need_bytes = -1;
jaroslav@694:   private byte[] crcbuf=new byte[4];
jaroslav@694: 
jaroslav@694:   GZIPHeader gheader = null;
jaroslav@694: 
jaroslav@694:   int inflateReset(){
jaroslav@694:     if(z == null) return Z_STREAM_ERROR;
jaroslav@694:     
jaroslav@694:     z.total_in = z.total_out = 0;
jaroslav@694:     z.msg = null;
jaroslav@694:     this.mode = HEAD;
jaroslav@694:     this.need_bytes = -1;
jaroslav@694:     this.blocks.reset();
jaroslav@694:     return Z_OK;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   int inflateEnd(){
jaroslav@694:     if(blocks != null){
jaroslav@694:       blocks.free();
jaroslav@694:     }
jaroslav@694:     return Z_OK;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   Inflate(ZStream z){
jaroslav@694:     this.z=z;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   int inflateInit(int w){
jaroslav@694:     z.msg = null;
jaroslav@694:     blocks = null;
jaroslav@694: 
jaroslav@694:     // handle undocumented wrap option (no zlib header or check)
jaroslav@694:     wrap = 0;
jaroslav@694:     if(w < 0){
jaroslav@694:       w = - w;
jaroslav@694:     }
jaroslav@694:     else {
jaroslav@694:       wrap = (w >> 4) + 1;
jaroslav@694:       if(w < 48)
jaroslav@694:         w &= 15;
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     if(w<8 ||w>15){
jaroslav@694:       inflateEnd();
jaroslav@694:       return Z_STREAM_ERROR;
jaroslav@694:     }
jaroslav@694:     if(blocks != null && wbits != w){
jaroslav@694:       blocks.free();
jaroslav@694:       blocks=null;
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     // set window size
jaroslav@694:     wbits=w;
jaroslav@694: 
jaroslav@694:     this.blocks=new InfBlocks(z, 1<<w);
jaroslav@694: 
jaroslav@694:     // reset state
jaroslav@694:     inflateReset();
jaroslav@694: 
jaroslav@694:     return Z_OK;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   int inflate(int f){
jaroslav@694:     int hold = 0;
jaroslav@694: 
jaroslav@694:     int r;
jaroslav@694:     int b;
jaroslav@694: 
jaroslav@694:     if(z == null || z.next_in == null){
jaroslav@694:       if(f == Z_FINISH && this.mode==HEAD)
jaroslav@694:         return Z_OK; 
jaroslav@694:       return Z_STREAM_ERROR;
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     f = f == Z_FINISH ? Z_BUF_ERROR : Z_OK;
jaroslav@694:     r = Z_BUF_ERROR;
jaroslav@694:     while (true){
jaroslav@694: 
jaroslav@694:       switch (this.mode){
jaroslav@694:       case HEAD:
jaroslav@694:         if(wrap==0){
jaroslav@694: 	  this.mode = BLOCKS;
jaroslav@694:           break;
jaroslav@694:         } 
jaroslav@694: 
jaroslav@694:         try { r=readBytes(2, r, f); }
jaroslav@694:         catch(Return e){ return e.r; }
jaroslav@694: 
jaroslav@694:         if((wrap&2)!=0 && this.need == 0x8b1fL) {   // gzip header
jaroslav@694: 	  z.adler=new CRC32();
jaroslav@694:           checksum(2, this.need);
jaroslav@694: 
jaroslav@694:           if(gheader==null) 
jaroslav@694:             gheader=new GZIPHeader();
jaroslav@694: 
jaroslav@694:           this.mode = FLAGS;
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         flags = 0;
jaroslav@694: 
jaroslav@694:         this.method = ((int)this.need)&0xff;
jaroslav@694:         b=((int)(this.need>>8))&0xff;
jaroslav@694: 
jaroslav@694:         if((wrap&1)==0 ||  // check if zlib header allowed
jaroslav@694:            (((this.method << 8)+b) % 31)!=0){
jaroslav@694:           this.mode = BAD;
jaroslav@694:           z.msg = "incorrect header check";
jaroslav@694:           // since zlib 1.2, it is allowted to inflateSync for this case.
jaroslav@694:           /*
jaroslav@694:           this.marker = 5;       // can't try inflateSync
jaroslav@694:           */
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         if((this.method&0xf)!=Z_DEFLATED){
jaroslav@694:           this.mode = BAD;
jaroslav@694:           z.msg="unknown compression method";
jaroslav@694:           // since zlib 1.2, it is allowted to inflateSync for this case.
jaroslav@694: 	  /*
jaroslav@694:           this.marker = 5;       // can't try inflateSync
jaroslav@694: 	  */
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         if((this.method>>4)+8>this.wbits){
jaroslav@694:           this.mode = BAD;
jaroslav@694:           z.msg="invalid window size";
jaroslav@694:           // since zlib 1.2, it is allowted to inflateSync for this case.
jaroslav@694: 	  /*
jaroslav@694:           this.marker = 5;       // can't try inflateSync
jaroslav@694: 	  */
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         z.adler=new Adler32();
jaroslav@694: 
jaroslav@694:         if((b&PRESET_DICT)==0){
jaroslav@694:           this.mode = BLOCKS;
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694:         this.mode = DICT4;
jaroslav@694:       case DICT4:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need=((z.next_in[z.next_in_index++]&0xff)<<24)&0xff000000L;
jaroslav@694:         this.mode=DICT3;
jaroslav@694:       case DICT3:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need+=((z.next_in[z.next_in_index++]&0xff)<<16)&0xff0000L;
jaroslav@694:         this.mode=DICT2;
jaroslav@694:       case DICT2:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need+=((z.next_in[z.next_in_index++]&0xff)<<8)&0xff00L;
jaroslav@694:         this.mode=DICT1;
jaroslav@694:       case DICT1:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need += (z.next_in[z.next_in_index++]&0xffL);
jaroslav@694:         z.adler.reset(this.need);
jaroslav@694:         this.mode = DICT0;
jaroslav@694:         return Z_NEED_DICT;
jaroslav@694:       case DICT0:
jaroslav@694:         this.mode = BAD;
jaroslav@694:         z.msg = "need dictionary";
jaroslav@694:         this.marker = 0;       // can try inflateSync
jaroslav@694:         return Z_STREAM_ERROR;
jaroslav@694:       case BLOCKS:
jaroslav@694:         r = this.blocks.proc(r);
jaroslav@694:         if(r == Z_DATA_ERROR){
jaroslav@694:           this.mode = BAD;
jaroslav@694:           this.marker = 0;     // can try inflateSync
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694:         if(r == Z_OK){
jaroslav@694:           r = f;
jaroslav@694:         }
jaroslav@694:         if(r != Z_STREAM_END){
jaroslav@694:           return r;
jaroslav@694:         }
jaroslav@694:         r = f;
jaroslav@694:         this.was=z.adler.getValue();
jaroslav@694:         this.blocks.reset();
jaroslav@694:         if(this.wrap==0){
jaroslav@694:           this.mode=DONE;
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694:         this.mode=CHECK4;
jaroslav@694:       case CHECK4:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need=((z.next_in[z.next_in_index++]&0xff)<<24)&0xff000000L;
jaroslav@694:         this.mode=CHECK3;
jaroslav@694:       case CHECK3:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need+=((z.next_in[z.next_in_index++]&0xff)<<16)&0xff0000L;
jaroslav@694:         this.mode = CHECK2;
jaroslav@694:       case CHECK2:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need+=((z.next_in[z.next_in_index++]&0xff)<<8)&0xff00L;
jaroslav@694:         this.mode = CHECK1;
jaroslav@694:       case CHECK1:
jaroslav@694: 
jaroslav@694:         if(z.avail_in==0)return r;r=f;
jaroslav@694: 
jaroslav@694:         z.avail_in--; z.total_in++;
jaroslav@694:         this.need+=(z.next_in[z.next_in_index++]&0xffL);
jaroslav@694: 
jaroslav@694:         if(flags!=0){  // gzip
jaroslav@694:           this.need = ((this.need&0xff000000)>>24 | 
jaroslav@694:                           (this.need&0x00ff0000)>>8 | 
jaroslav@694:                           (this.need&0x0000ff00)<<8 | 
jaroslav@694:                           (this.need&0x0000ffff)<<24)&0xffffffffL;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         if(((int)(this.was)) != ((int)(this.need))){
jaroslav@694:           z.msg = "incorrect data check";
jaroslav@694:           // chack is delayed
jaroslav@694:           /*
jaroslav@694:           this.mode = BAD;
jaroslav@694:           this.marker = 5;       // can't try inflateSync
jaroslav@694:           break;
jaroslav@694: 	  */
jaroslav@694:         }
jaroslav@694:         else if(flags!=0 && gheader!=null){
jaroslav@694:           gheader.crc = this.need; 
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         this.mode = LENGTH;
jaroslav@694:       case LENGTH:
jaroslav@694:         if (wrap!=0 && flags!=0) {
jaroslav@694: 
jaroslav@694:           try { r=readBytes(4, r, f); }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694: 
jaroslav@694:           if(z.msg!=null && z.msg.equals("incorrect data check")){
jaroslav@694:             this.mode = BAD;
jaroslav@694:             this.marker = 5;       // can't try inflateSync
jaroslav@694:             break;
jaroslav@694:           }
jaroslav@694: 
jaroslav@694:           if (this.need != (z.total_out & 0xffffffffL)) {
jaroslav@694:             z.msg = "incorrect length check";
jaroslav@694:             this.mode = BAD;
jaroslav@694:             break;
jaroslav@694:           }
jaroslav@694:           z.msg = null;
jaroslav@694:         }
jaroslav@694:         else {
jaroslav@694:           if(z.msg!=null && z.msg.equals("incorrect data check")){
jaroslav@694:             this.mode = BAD;
jaroslav@694:             this.marker = 5;       // can't try inflateSync
jaroslav@694:             break;
jaroslav@694:           }
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         this.mode = DONE;
jaroslav@694:       case DONE:
jaroslav@694:         return Z_STREAM_END;
jaroslav@694:       case BAD:
jaroslav@694:         return Z_DATA_ERROR;
jaroslav@694: 
jaroslav@694:       case FLAGS:
jaroslav@694: 
jaroslav@694:         try { r=readBytes(2, r, f); }
jaroslav@694:         catch(Return e){ return e.r; }
jaroslav@694: 
jaroslav@694:         flags = ((int)this.need)&0xffff;
jaroslav@694: 
jaroslav@694:         if ((flags & 0xff) != Z_DEFLATED) {
jaroslav@694:           z.msg = "unknown compression method";
jaroslav@694:           this.mode = BAD; 
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694:         if ((flags & 0xe000)!=0) {
jaroslav@694:           z.msg = "unknown header flags set";
jaroslav@694:           this.mode = BAD; 
jaroslav@694:           break;
jaroslav@694:         }
jaroslav@694: 
jaroslav@694:         if ((flags & 0x0200)!=0){
jaroslav@694:           checksum(2, this.need);
jaroslav@694:         } 
jaroslav@694: 
jaroslav@694:         this.mode = TIME;
jaroslav@694: 
jaroslav@694:       case TIME:
jaroslav@694:         try { r=readBytes(4, r, f); }
jaroslav@694:         catch(Return e){ return e.r; }
jaroslav@694:         if(gheader!=null)
jaroslav@694:           gheader.time = this.need;
jaroslav@694:         if ((flags & 0x0200)!=0){
jaroslav@694:           checksum(4, this.need);
jaroslav@694:         }
jaroslav@694:         this.mode = OS;
jaroslav@694:       case OS:
jaroslav@694:         try { r=readBytes(2, r, f); }
jaroslav@694:         catch(Return e){ return e.r; }
jaroslav@694:         if(gheader!=null){
jaroslav@694:           gheader.xflags = ((int)this.need)&0xff;
jaroslav@694:           gheader.os = (((int)this.need)>>8)&0xff;
jaroslav@694:         }
jaroslav@694:         if ((flags & 0x0200)!=0){
jaroslav@694:           checksum(2, this.need);
jaroslav@694:         }
jaroslav@694:         this.mode = EXLEN;
jaroslav@694:       case EXLEN:
jaroslav@694:         if ((flags & 0x0400)!=0) {
jaroslav@694:           try { r=readBytes(2, r, f); }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694:           if(gheader!=null){
jaroslav@694:             gheader.extra = new byte[((int)this.need)&0xffff];
jaroslav@694:           }
jaroslav@694:           if ((flags & 0x0200)!=0){
jaroslav@694:             checksum(2, this.need);
jaroslav@694:           }
jaroslav@694:         }
jaroslav@694:         else if(gheader!=null){
jaroslav@694:           gheader.extra=null;
jaroslav@694:         }
jaroslav@694:         this.mode = EXTRA;
jaroslav@694: 
jaroslav@694:       case EXTRA:
jaroslav@694:         if ((flags & 0x0400)!=0) {
jaroslav@694:           try { 
jaroslav@694:             r=readBytes(r, f);
jaroslav@694:             if(gheader!=null){
jaroslav@694:               byte[] foo = tmp_array;
jaroslav@694:               tmp_array=null;
jaroslav@694:               if(foo.length == gheader.extra.length){
jaroslav@694:                 System.arraycopy(foo, 0, gheader.extra, 0, foo.length);
jaroslav@694: 	      }
jaroslav@694:               else{
jaroslav@694:                 z.msg = "bad extra field length";
jaroslav@694:                 this.mode = BAD; 
jaroslav@694:                 break;
jaroslav@694: 	      }
jaroslav@694:             }
jaroslav@694:           }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694:         }
jaroslav@694:         else if(gheader!=null){
jaroslav@694:           gheader.extra=null;
jaroslav@694: 	}
jaroslav@694: 	this.mode = NAME;
jaroslav@694:       case NAME:
jaroslav@694: 	if ((flags & 0x0800)!=0) {
jaroslav@694:           try { 
jaroslav@694:             r=readString(r, f);
jaroslav@694:             if(gheader!=null){
jaroslav@694:               gheader.name=tmp_array;
jaroslav@694:             }
jaroslav@694:             tmp_array=null;
jaroslav@694:           }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694:         }
jaroslav@694:         else if(gheader!=null){
jaroslav@694:           gheader.name=null;
jaroslav@694: 	}
jaroslav@694:         this.mode = COMMENT;
jaroslav@694:       case COMMENT:
jaroslav@694:         if ((flags & 0x1000)!=0) {
jaroslav@694:           try { 
jaroslav@694:             r=readString(r, f);
jaroslav@694:             if(gheader!=null){
jaroslav@694:               gheader.comment=tmp_array;
jaroslav@694:             }
jaroslav@694:             tmp_array=null;
jaroslav@694:           }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694:         }
jaroslav@694:         else if(gheader!=null){
jaroslav@694:           gheader.comment=null;
jaroslav@694: 	}
jaroslav@694:         this.mode = HCRC;
jaroslav@694:       case HCRC:
jaroslav@694: 	if ((flags & 0x0200)!=0) {
jaroslav@694:           try { r=readBytes(2, r, f); }
jaroslav@694:           catch(Return e){ return e.r; }
jaroslav@694:           if(gheader!=null){
jaroslav@694:             gheader.hcrc=(int)(this.need&0xffff);
jaroslav@694:           }
jaroslav@694:           if(this.need != (z.adler.getValue()&0xffffL)){
jaroslav@694:             this.mode = BAD;
jaroslav@694:             z.msg = "header crc mismatch";
jaroslav@694:             this.marker = 5;       // can't try inflateSync
jaroslav@694:             break;
jaroslav@694:           }
jaroslav@694:         }
jaroslav@694:         z.adler = new CRC32();
jaroslav@694: 
jaroslav@694:         this.mode = BLOCKS;
jaroslav@694:         break;
jaroslav@694:       default:
jaroslav@694:         return Z_STREAM_ERROR;
jaroslav@694:       }
jaroslav@694:     }
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   int inflateSetDictionary(byte[] dictionary, int dictLength){
jaroslav@694:     if(z==null || (this.mode != DICT0 && this.wrap != 0)){
jaroslav@694:       return Z_STREAM_ERROR;
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     int index=0;
jaroslav@694:     int length = dictLength;
jaroslav@694: 
jaroslav@694:     if(this.mode==DICT0){
jaroslav@694:       long adler_need=z.adler.getValue();
jaroslav@694:       z.adler.reset();
jaroslav@694:       z.adler.update(dictionary, 0, dictLength);
jaroslav@694:       if(z.adler.getValue()!=adler_need){
jaroslav@694:         return Z_DATA_ERROR;
jaroslav@694:       }
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     z.adler.reset();
jaroslav@694: 
jaroslav@694:     if(length >= (1<<this.wbits)){
jaroslav@694:       length = (1<<this.wbits)-1;
jaroslav@694:       index=dictLength - length;
jaroslav@694:     }
jaroslav@694:     this.blocks.set_dictionary(dictionary, index, length);
jaroslav@694:     this.mode = BLOCKS;
jaroslav@694:     return Z_OK;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   static private byte[] mark = {(byte)0, (byte)0, (byte)0xff, (byte)0xff};
jaroslav@694: 
jaroslav@694:   int inflateSync(){
jaroslav@694:     int n;       // number of bytes to look at
jaroslav@694:     int p;       // pointer to bytes
jaroslav@694:     int m;       // number of marker bytes found in a row
jaroslav@694:     long r, w;   // temporaries to save total_in and total_out
jaroslav@694: 
jaroslav@694:     // set up
jaroslav@694:     if(z == null)
jaroslav@694:       return Z_STREAM_ERROR;
jaroslav@694:     if(this.mode != BAD){
jaroslav@694:       this.mode = BAD;
jaroslav@694:       this.marker = 0;
jaroslav@694:     }
jaroslav@694:     if((n=z.avail_in)==0)
jaroslav@694:       return Z_BUF_ERROR;
jaroslav@694: 
jaroslav@694:     p=z.next_in_index;
jaroslav@694:     m=this.marker;
jaroslav@694:     // search
jaroslav@694:     while (n!=0 && m < 4){
jaroslav@694:       if(z.next_in[p] == mark[m]){
jaroslav@694:         m++;
jaroslav@694:       }
jaroslav@694:       else if(z.next_in[p]!=0){
jaroslav@694:         m = 0;
jaroslav@694:       }
jaroslav@694:       else{
jaroslav@694:         m = 4 - m;
jaroslav@694:       }
jaroslav@694:       p++; n--;
jaroslav@694:     }
jaroslav@694: 
jaroslav@694:     // restore
jaroslav@694:     z.total_in += p-z.next_in_index;
jaroslav@694:     z.next_in_index = p;
jaroslav@694:     z.avail_in = n;
jaroslav@694:     this.marker = m;
jaroslav@694: 
jaroslav@694:     // return no joy or set up to restart on a new block
jaroslav@694:     if(m != 4){
jaroslav@694:       return Z_DATA_ERROR;
jaroslav@694:     }
jaroslav@694:     r=z.total_in;  w=z.total_out;
jaroslav@694:     inflateReset();
jaroslav@694:     z.total_in=r;  z.total_out = w;
jaroslav@694:     this.mode = BLOCKS;
jaroslav@694: 
jaroslav@694:     return Z_OK;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   // Returns true if inflate is currently at the end of a block generated
jaroslav@694:   // by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
jaroslav@694:   // implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
jaroslav@694:   // but removes the length bytes of the resulting empty stored block. When
jaroslav@694:   // decompressing, PPP checks that at the end of input packet, inflate is
jaroslav@694:   // waiting for these length bytes.
jaroslav@694:   int inflateSyncPoint(){
jaroslav@694:     if(z == null || this.blocks == null)
jaroslav@694:       return Z_STREAM_ERROR;
jaroslav@694:     return this.blocks.sync_point();
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   private int readBytes(int n, int r, int f) throws Return{
jaroslav@694:     if(need_bytes == -1){
jaroslav@694:       need_bytes=n;
jaroslav@694:       this.need=0;
jaroslav@694:     }
jaroslav@694:     while(need_bytes>0){
jaroslav@694:       if(z.avail_in==0){ throw new Return(r); }; r=f;
jaroslav@694:       z.avail_in--; z.total_in++;
jaroslav@694:       this.need = this.need | 
jaroslav@694: 	((z.next_in[z.next_in_index++]&0xff)<<((n-need_bytes)*8));
jaroslav@694:       need_bytes--;
jaroslav@694:     }
jaroslav@694:     if(n==2){
jaroslav@694:       this.need&=0xffffL;
jaroslav@694:     }
jaroslav@694:     else if(n==4) {
jaroslav@694:       this.need&=0xffffffffL;
jaroslav@694:     }
jaroslav@694:     need_bytes=-1;
jaroslav@694:     return r;
jaroslav@694:   }
jaroslav@694:   class Return extends Exception{
jaroslav@694:     int r;
jaroslav@694:     Return(int r){this.r=r; }
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   private byte[] tmp_array;
jaroslav@694:   private int readString(int r, int f) throws Return{
jaroslav@694:     int b=0; 
jaroslav@694:     byte[] arr = new byte[4092];
jaroslav@694:     int at = 0;
jaroslav@694:     do {
jaroslav@694:       if(z.avail_in==0){ throw new Return(r); }; r=f;
jaroslav@694:       z.avail_in--; z.total_in++;
jaroslav@694:       b = z.next_in[z.next_in_index];
jaroslav@694:       if(b!=0) arr = append(arr, z.next_in[z.next_in_index], at++);
jaroslav@694:       z.adler.update(z.next_in, z.next_in_index, 1);
jaroslav@694:       z.next_in_index++;
jaroslav@694:     }while(b!=0);
jaroslav@694:     
jaroslav@694:     tmp_array = copy(arr, at);
jaroslav@694:     
jaroslav@694:     return r;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   private int readBytes(int r, int f) throws Return{
jaroslav@694:     int b=0; 
jaroslav@694:     byte[] arr = new byte[4092];
jaroslav@694:     int at = 0;
jaroslav@694:     while(this.need>0){
jaroslav@694:       if(z.avail_in==0){ throw new Return(r); }; r=f;
jaroslav@694:       z.avail_in--; z.total_in++;
jaroslav@694:       b = z.next_in[z.next_in_index];
jaroslav@694:       arr = append(arr, z.next_in[z.next_in_index], at++);
jaroslav@694:       z.adler.update(z.next_in, z.next_in_index, 1);
jaroslav@694:       z.next_in_index++;
jaroslav@694:       this.need--;
jaroslav@694:     }
jaroslav@694:     
jaroslav@694:     tmp_array = copy(arr, at);
jaroslav@694:     
jaroslav@694:     return r;
jaroslav@694:   }
jaroslav@694:   
jaroslav@694:   private static byte[] copy(byte[] arr, int len) {
jaroslav@694:       byte[] ret = new byte[len];
jaroslav@694:       org.apidesign.bck2brwsr.emul.lang.System.arraycopy(arr, 0, ret, 0, len);
jaroslav@694:       return ret;
jaroslav@694:   }
jaroslav@694:   private static byte[] append(byte[] arr, byte b, int index) {
jaroslav@694:       arr[index] = b;
jaroslav@694:       return arr;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   private void checksum(int n, long v){
jaroslav@694:     for(int i=0; i<n; i++){
jaroslav@694:       crcbuf[i]=(byte)(v&0xff);
jaroslav@694:       v>>=8;
jaroslav@694:     }
jaroslav@694:     z.adler.update(crcbuf, 0, n);
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   public GZIPHeader getGZIPHeader(){
jaroslav@694:     return gheader;
jaroslav@694:   }
jaroslav@694: 
jaroslav@694:   boolean inParsingHeader(){
jaroslav@694:     switch(mode){
jaroslav@694:       case HEAD:
jaroslav@694:       case DICT4:
jaroslav@694:       case DICT3:
jaroslav@694:       case DICT2:
jaroslav@694:       case DICT1:
jaroslav@694:       case FLAGS:
jaroslav@694:       case TIME:
jaroslav@694:       case OS:
jaroslav@694:       case EXLEN:
jaroslav@694:       case EXTRA:
jaroslav@694:       case NAME:
jaroslav@694:       case COMMENT:
jaroslav@694:       case HCRC:
jaroslav@694: 	return true;
jaroslav@694:       default:
jaroslav@694: 	return false;
jaroslav@694:     }
jaroslav@694:   }
jaroslav@694: }