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diff --git a/app/src/main/java/com/jcraft/jzlib/Deflate.java b/app/src/main/java/com/jcraft/jzlib/Deflate.java
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+/* -*-mode:java; c-basic-offset:2; -*- */
+/*
+Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice,
+ this list of conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the distribution.
+
+ 3. The names of the authors may not be used to endorse or promote products
+ derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
+INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+/*
+ * This program is based on zlib-1.1.3, so all credit should go authors
+ * Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
+ * and contributors of zlib.
+ */
+
+package com.jcraft.jzlib;
+
+public
+final class Deflate{
+
+ static final private int MAX_MEM_LEVEL=9;
+
+ static final private int Z_DEFAULT_COMPRESSION=-1;
+
+ static final private int MAX_WBITS=15; // 32K LZ77 window
+ static final private int DEF_MEM_LEVEL=8;
+
+ static class Config{
+ int good_length; // reduce lazy search above this match length
+ int max_lazy; // do not perform lazy search above this match length
+ int nice_length; // quit search above this match length
+ int max_chain;
+ int func;
+ Config(int good_length, int max_lazy,
+ int nice_length, int max_chain, int func){
+ this.good_length=good_length;
+ this.max_lazy=max_lazy;
+ this.nice_length=nice_length;
+ this.max_chain=max_chain;
+ this.func=func;
+ }
+ }
+
+ static final private int STORED=0;
+ static final private int FAST=1;
+ static final private int SLOW=2;
+ static final private Config[] config_table;
+ static{
+ config_table=new Config[10];
+ // good lazy nice chain
+ config_table[0]=new Config(0, 0, 0, 0, STORED);
+ config_table[1]=new Config(4, 4, 8, 4, FAST);
+ config_table[2]=new Config(4, 5, 16, 8, FAST);
+ config_table[3]=new Config(4, 6, 32, 32, FAST);
+
+ config_table[4]=new Config(4, 4, 16, 16, SLOW);
+ config_table[5]=new Config(8, 16, 32, 32, SLOW);
+ config_table[6]=new Config(8, 16, 128, 128, SLOW);
+ config_table[7]=new Config(8, 32, 128, 256, SLOW);
+ config_table[8]=new Config(32, 128, 258, 1024, SLOW);
+ config_table[9]=new Config(32, 258, 258, 4096, SLOW);
+ }
+
+ static final private String[] z_errmsg = {
+ "need dictionary", // Z_NEED_DICT 2
+ "stream end", // Z_STREAM_END 1
+ "", // Z_OK 0
+ "file error", // Z_ERRNO (-1)
+ "stream error", // Z_STREAM_ERROR (-2)
+ "data error", // Z_DATA_ERROR (-3)
+ "insufficient memory", // Z_MEM_ERROR (-4)
+ "buffer error", // Z_BUF_ERROR (-5)
+ "incompatible version",// Z_VERSION_ERROR (-6)
+ ""
+ };
+
+ // block not completed, need more input or more output
+ static final private int NeedMore=0;
+
+ // block flush performed
+ static final private int BlockDone=1;
+
+ // finish started, need only more output at next deflate
+ static final private int FinishStarted=2;
+
+ // finish done, accept no more input or output
+ static final private int FinishDone=3;
+
+ // preset dictionary flag in zlib header
+ static final private int PRESET_DICT=0x20;
+
+ static final private int Z_FILTERED=1;
+ static final private int Z_HUFFMAN_ONLY=2;
+ static final private int Z_DEFAULT_STRATEGY=0;
+
+ static final private int Z_NO_FLUSH=0;
+ static final private int Z_PARTIAL_FLUSH=1;
+ static final private int Z_SYNC_FLUSH=2;
+ static final private int Z_FULL_FLUSH=3;
+ static final private int Z_FINISH=4;
+
+ static final private int Z_OK=0;
+ static final private int Z_STREAM_END=1;
+ static final private int Z_NEED_DICT=2;
+ static final private int Z_ERRNO=-1;
+ static final private int Z_STREAM_ERROR=-2;
+ static final private int Z_DATA_ERROR=-3;
+ static final private int Z_MEM_ERROR=-4;
+ static final private int Z_BUF_ERROR=-5;
+ static final private int Z_VERSION_ERROR=-6;
+
+ static final private int INIT_STATE=42;
+ static final private int BUSY_STATE=113;
+ static final private int FINISH_STATE=666;
+
+ // The deflate compression method
+ static final private int Z_DEFLATED=8;
+
+ static final private int STORED_BLOCK=0;
+ static final private int STATIC_TREES=1;
+ static final private int DYN_TREES=2;
+
+ // The three kinds of block type
+ static final private int Z_BINARY=0;
+ static final private int Z_ASCII=1;
+ static final private int Z_UNKNOWN=2;
+
+ static final private int Buf_size=8*2;
+
+ // repeat previous bit length 3-6 times (2 bits of repeat count)
+ static final private int REP_3_6=16;
+
+ // repeat a zero length 3-10 times (3 bits of repeat count)
+ static final private int REPZ_3_10=17;
+
+ // repeat a zero length 11-138 times (7 bits of repeat count)
+ static final private int REPZ_11_138=18;
+
+ static final private int MIN_MATCH=3;
+ static final private int MAX_MATCH=258;
+ static final private int MIN_LOOKAHEAD=(MAX_MATCH+MIN_MATCH+1);
+
+ static final private int MAX_BITS=15;
+ static final private int D_CODES=30;
+ static final private int BL_CODES=19;
+ static final private int LENGTH_CODES=29;
+ static final private int LITERALS=256;
+ static final private int L_CODES=(LITERALS+1+LENGTH_CODES);
+ static final private int HEAP_SIZE=(2*L_CODES+1);
+
+ static final private int END_BLOCK=256;
+
+ ZStream strm; // pointer back to this zlib stream
+ int status; // as the name implies
+ byte[] pending_buf; // output still pending
+ int pending_buf_size; // size of pending_buf
+ int pending_out; // next pending byte to output to the stream
+ int pending; // nb of bytes in the pending buffer
+ int noheader; // suppress zlib header and adler32
+ byte data_type; // UNKNOWN, BINARY or ASCII
+ byte method; // STORED (for zip only) or DEFLATED
+ int last_flush; // value of flush param for previous deflate call
+
+ int w_size; // LZ77 window size (32K by default)
+ int w_bits; // log2(w_size) (8..16)
+ int w_mask; // w_size - 1
+
+ byte[] window;
+ // Sliding window. Input bytes are read into the second half of the window,
+ // and move to the first half later to keep a dictionary of at least wSize
+ // bytes. With this organization, matches are limited to a distance of
+ // wSize-MAX_MATCH bytes, but this ensures that IO is always
+ // performed with a length multiple of the block size. Also, it limits
+ // the window size to 64K, which is quite useful on MSDOS.
+ // To do: use the user input buffer as sliding window.
+
+ int window_size;
+ // Actual size of window: 2*wSize, except when the user input buffer
+ // is directly used as sliding window.
+
+ short[] prev;
+ // Link to older string with same hash index. To limit the size of this
+ // array to 64K, this link is maintained only for the last 32K strings.
+ // An index in this array is thus a window index modulo 32K.
+
+ short[] head; // Heads of the hash chains or NIL.
+
+ int ins_h; // hash index of string to be inserted
+ int hash_size; // number of elements in hash table
+ int hash_bits; // log2(hash_size)
+ int hash_mask; // hash_size-1
+
+ // Number of bits by which ins_h must be shifted at each input
+ // step. It must be such that after MIN_MATCH steps, the oldest
+ // byte no longer takes part in the hash key, that is:
+ // hash_shift * MIN_MATCH >= hash_bits
+ int hash_shift;
+
+ // Window position at the beginning of the current output block. Gets
+ // negative when the window is moved backwards.
+
+ int block_start;
+
+ int match_length; // length of best match
+ int prev_match; // previous match
+ int match_available; // set if previous match exists
+ int strstart; // start of string to insert
+ int match_start; // start of matching string
+ int lookahead; // number of valid bytes ahead in window
+
+ // Length of the best match at previous step. Matches not greater than this
+ // are discarded. This is used in the lazy match evaluation.
+ int prev_length;
+
+ // To speed up deflation, hash chains are never searched beyond this
+ // length. A higher limit improves compression ratio but degrades the speed.
+ int max_chain_length;
+
+ // Attempt to find a better match only when the current match is strictly
+ // smaller than this value. This mechanism is used only for compression
+ // levels >= 4.
+ int max_lazy_match;
+
+ // Insert new strings in the hash table only if the match length is not
+ // greater than this length. This saves time but degrades compression.
+ // max_insert_length is used only for compression levels <= 3.
+
+ int level; // compression level (1..9)
+ int strategy; // favor or force Huffman coding
+
+ // Use a faster search when the previous match is longer than this
+ int good_match;
+
+ // Stop searching when current match exceeds this
+ int nice_match;
+
+ short[] dyn_ltree; // literal and length tree
+ short[] dyn_dtree; // distance tree
+ short[] bl_tree; // Huffman tree for bit lengths
+
+ Tree l_desc=new Tree(); // desc for literal tree
+ Tree d_desc=new Tree(); // desc for distance tree
+ Tree bl_desc=new Tree(); // desc for bit length tree
+
+ // number of codes at each bit length for an optimal tree
+ short[] bl_count=new short[MAX_BITS+1];
+
+ // heap used to build the Huffman trees
+ int[] heap=new int[2*L_CODES+1];
+
+ int heap_len; // number of elements in the heap
+ int heap_max; // element of largest frequency
+ // The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.
+ // The same heap array is used to build all trees.
+
+ // Depth of each subtree used as tie breaker for trees of equal frequency
+ byte[] depth=new byte[2*L_CODES+1];
+
+ int l_buf; // index for literals or lengths */
+
+ // Size of match buffer for literals/lengths. There are 4 reasons for
+ // limiting lit_bufsize to 64K:
+ // - frequencies can be kept in 16 bit counters
+ // - if compression is not successful for the first block, all input
+ // data is still in the window so we can still emit a stored block even
+ // when input comes from standard input. (This can also be done for
+ // all blocks if lit_bufsize is not greater than 32K.)
+ // - if compression is not successful for a file smaller than 64K, we can
+ // even emit a stored file instead of a stored block (saving 5 bytes).
+ // This is applicable only for zip (not gzip or zlib).
+ // - creating new Huffman trees less frequently may not provide fast
+ // adaptation to changes in the input data statistics. (Take for
+ // example a binary file with poorly compressible code followed by
+ // a highly compressible string table.) Smaller buffer sizes give
+ // fast adaptation but have of course the overhead of transmitting
+ // trees more frequently.
+ // - I can't count above 4
+ int lit_bufsize;
+
+ int last_lit; // running index in l_buf
+
+ // Buffer for distances. To simplify the code, d_buf and l_buf have
+ // the same number of elements. To use different lengths, an extra flag
+ // array would be necessary.
+
+ int d_buf; // index of pendig_buf
+
+ int opt_len; // bit length of current block with optimal trees
+ int static_len; // bit length of current block with static trees
+ int matches; // number of string matches in current block
+ int last_eob_len; // bit length of EOB code for last block
+
+ // Output buffer. bits are inserted starting at the bottom (least
+ // significant bits).
+ short bi_buf;
+
+ // Number of valid bits in bi_buf. All bits above the last valid bit
+ // are always zero.
+ int bi_valid;
+
+ Deflate(){
+ dyn_ltree=new short[HEAP_SIZE*2];
+ dyn_dtree=new short[(2*D_CODES+1)*2]; // distance tree
+ bl_tree=new short[(2*BL_CODES+1)*2]; // Huffman tree for bit lengths
+ }
+
+ void lm_init() {
+ window_size=2*w_size;
+
+ head[hash_size-1]=0;
+ for(int i=0; i<hash_size-1; i++){
+ head[i]=0;
+ }
+
+ // Set the default configuration parameters:
+ max_lazy_match = Deflate.config_table[level].max_lazy;
+ good_match = Deflate.config_table[level].good_length;
+ nice_match = Deflate.config_table[level].nice_length;
+ max_chain_length = Deflate.config_table[level].max_chain;
+
+ strstart = 0;
+ block_start = 0;
+ lookahead = 0;
+ match_length = prev_length = MIN_MATCH-1;
+ match_available = 0;
+ ins_h = 0;
+ }
+
+ // Initialize the tree data structures for a new zlib stream.
+ void tr_init(){
+
+ l_desc.dyn_tree = dyn_ltree;
+ l_desc.stat_desc = StaticTree.static_l_desc;
+
+ d_desc.dyn_tree = dyn_dtree;
+ d_desc.stat_desc = StaticTree.static_d_desc;
+
+ bl_desc.dyn_tree = bl_tree;
+ bl_desc.stat_desc = StaticTree.static_bl_desc;
+
+ bi_buf = 0;
+ bi_valid = 0;
+ last_eob_len = 8; // enough lookahead for inflate
+
+ // Initialize the first block of the first file:
+ init_block();
+ }
+
+ void init_block(){
+ // Initialize the trees.
+ for(int i = 0; i < L_CODES; i++) dyn_ltree[i*2] = 0;
+ for(int i= 0; i < D_CODES; i++) dyn_dtree[i*2] = 0;
+ for(int i= 0; i < BL_CODES; i++) bl_tree[i*2] = 0;
+
+ dyn_ltree[END_BLOCK*2] = 1;
+ opt_len = static_len = 0;
+ last_lit = matches = 0;
+ }
+
+ // Restore the heap property by moving down the tree starting at node k,
+ // exchanging a node with the smallest of its two sons if necessary, stopping
+ // when the heap property is re-established (each father smaller than its
+ // two sons).
+ void pqdownheap(short[] tree, // the tree to restore
+ int k // node to move down
+ ){
+ int v = heap[k];
+ int j = k << 1; // left son of k
+ while (j <= heap_len) {
+ // Set j to the smallest of the two sons:
+ if (j < heap_len &&
+ smaller(tree, heap[j+1], heap[j], depth)){
+ j++;
+ }
+ // Exit if v is smaller than both sons
+ if(smaller(tree, v, heap[j], depth)) break;
+
+ // Exchange v with the smallest son
+ heap[k]=heap[j]; k = j;
+ // And continue down the tree, setting j to the left son of k
+ j <<= 1;
+ }
+ heap[k] = v;
+ }
+
+ static boolean smaller(short[] tree, int n, int m, byte[] depth){
+ short tn2=tree[n*2];
+ short tm2=tree[m*2];
+ return (tn2<tm2 ||
+ (tn2==tm2 && depth[n] <= depth[m]));
+ }
+
+ // Scan a literal or distance tree to determine the frequencies of the codes
+ // in the bit length tree.
+ void scan_tree (short[] tree,// the tree to be scanned
+ int max_code // and its largest code of non zero frequency
+ ){
+ int n; // iterates over all tree elements
+ int prevlen = -1; // last emitted length
+ int curlen; // length of current code
+ int nextlen = tree[0*2+1]; // length of next code
+ int count = 0; // repeat count of the current code
+ int max_count = 7; // max repeat count
+ int min_count = 4; // min repeat count
+
+ if (nextlen == 0){ max_count = 138; min_count = 3; }
+ tree[(max_code+1)*2+1] = (short)0xffff; // guard
+
+ for(n = 0; n <= max_code; n++) {
+ curlen = nextlen; nextlen = tree[(n+1)*2+1];
+ if(++count < max_count && curlen == nextlen) {
+ continue;
+ }
+ else if(count < min_count) {
+ bl_tree[curlen*2] += count;
+ }
+ else if(curlen != 0) {
+ if(curlen != prevlen) bl_tree[curlen*2]++;
+ bl_tree[REP_3_6*2]++;
+ }
+ else if(count <= 10) {
+ bl_tree[REPZ_3_10*2]++;
+ }
+ else{
+ bl_tree[REPZ_11_138*2]++;
+ }
+ count = 0; prevlen = curlen;
+ if(nextlen == 0) {
+ max_count = 138; min_count = 3;
+ }
+ else if(curlen == nextlen) {
+ max_count = 6; min_count = 3;
+ }
+ else{
+ max_count = 7; min_count = 4;
+ }
+ }
+ }
+
+ // Construct the Huffman tree for the bit lengths and return the index in
+ // bl_order of the last bit length code to send.
+ int build_bl_tree(){
+ int max_blindex; // index of last bit length code of non zero freq
+
+ // Determine the bit length frequencies for literal and distance trees
+ scan_tree(dyn_ltree, l_desc.max_code);
+ scan_tree(dyn_dtree, d_desc.max_code);
+
+ // Build the bit length tree:
+ bl_desc.build_tree(this);
+ // opt_len now includes the length of the tree representations, except
+ // the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
+
+ // Determine the number of bit length codes to send. The pkzip format
+ // requires that at least 4 bit length codes be sent. (appnote.txt says
+ // 3 but the actual value used is 4.)
+ for (max_blindex = BL_CODES-1; max_blindex >= 3; max_blindex--) {
+ if (bl_tree[Tree.bl_order[max_blindex]*2+1] != 0) break;
+ }
+ // Update opt_len to include the bit length tree and counts
+ opt_len += 3*(max_blindex+1) + 5+5+4;
+
+ return max_blindex;
+ }
+
+
+ // Send the header for a block using dynamic Huffman trees: the counts, the
+ // lengths of the bit length codes, the literal tree and the distance tree.
+ // IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
+ void send_all_trees(int lcodes, int dcodes, int blcodes){
+ int rank; // index in bl_order
+
+ send_bits(lcodes-257, 5); // not +255 as stated in appnote.txt
+ send_bits(dcodes-1, 5);
+ send_bits(blcodes-4, 4); // not -3 as stated in appnote.txt
+ for (rank = 0; rank < blcodes; rank++) {
+ send_bits(bl_tree[Tree.bl_order[rank]*2+1], 3);
+ }
+ send_tree(dyn_ltree, lcodes-1); // literal tree
+ send_tree(dyn_dtree, dcodes-1); // distance tree
+ }
+
+ // Send a literal or distance tree in compressed form, using the codes in
+ // bl_tree.
+ void send_tree (short[] tree,// the tree to be sent
+ int max_code // and its largest code of non zero frequency
+ ){
+ int n; // iterates over all tree elements
+ int prevlen = -1; // last emitted length
+ int curlen; // length of current code
+ int nextlen = tree[0*2+1]; // length of next code
+ int count = 0; // repeat count of the current code
+ int max_count = 7; // max repeat count
+ int min_count = 4; // min repeat count
+
+ if (nextlen == 0){ max_count = 138; min_count = 3; }
+
+ for (n = 0; n <= max_code; n++) {
+ curlen = nextlen; nextlen = tree[(n+1)*2+1];
+ if(++count < max_count && curlen == nextlen) {
+ continue;
+ }
+ else if(count < min_count) {
+ do { send_code(curlen, bl_tree); } while (--count != 0);
+ }
+ else if(curlen != 0){
+ if(curlen != prevlen){
+ send_code(curlen, bl_tree); count--;
+ }
+ send_code(REP_3_6, bl_tree);
+ send_bits(count-3, 2);
+ }
+ else if(count <= 10){
+ send_code(REPZ_3_10, bl_tree);
+ send_bits(count-3, 3);
+ }
+ else{
+ send_code(REPZ_11_138, bl_tree);
+ send_bits(count-11, 7);
+ }
+ count = 0; prevlen = curlen;
+ if(nextlen == 0){
+ max_count = 138; min_count = 3;
+ }
+ else if(curlen == nextlen){
+ max_count = 6; min_count = 3;
+ }
+ else{
+ max_count = 7; min_count = 4;
+ }
+ }
+ }
+
+ // Output a byte on the stream.
+ // IN assertion: there is enough room in pending_buf.
+ final void put_byte(byte[] p, int start, int len){
+ System.arraycopy(p, start, pending_buf, pending, len);
+ pending+=len;
+ }
+
+ final void put_byte(byte c){
+ pending_buf[pending++]=c;
+ }
+ final void put_short(int w) {
+ put_byte((byte)(w/*&0xff*/));
+ put_byte((byte)(w>>>8));
+ }
+ final void putShortMSB(int b){
+ put_byte((byte)(b>>8));
+ put_byte((byte)(b/*&0xff*/));
+ }
+
+ final void send_code(int c, short[] tree){
+ int c2=c*2;
+ send_bits((tree[c2]&0xffff), (tree[c2+1]&0xffff));
+ }
+
+ void send_bits(int value, int length){
+ int len = length;
+ if (bi_valid > (int)Buf_size - len) {
+ int val = value;
+// bi_buf |= (val << bi_valid);
+ bi_buf |= ((val << bi_valid)&0xffff);
+ put_short(bi_buf);
+ bi_buf = (short)(val >>> (Buf_size - bi_valid));
+ bi_valid += len - Buf_size;
+ } else {
+// bi_buf |= (value) << bi_valid;
+ bi_buf |= (((value) << bi_valid)&0xffff);
+ bi_valid += len;
+ }
+ }
+
+ // Send one empty static block to give enough lookahead for inflate.
+ // This takes 10 bits, of which 7 may remain in the bit buffer.
+ // The current inflate code requires 9 bits of lookahead. If the
+ // last two codes for the previous block (real code plus EOB) were coded
+ // on 5 bits or less, inflate may have only 5+3 bits of lookahead to decode
+ // the last real code. In this case we send two empty static blocks instead
+ // of one. (There are no problems if the previous block is stored or fixed.)
+ // To simplify the code, we assume the worst case of last real code encoded
+ // on one bit only.
+ void _tr_align(){
+ send_bits(STATIC_TREES<<1, 3);
+ send_code(END_BLOCK, StaticTree.static_ltree);
+
+ bi_flush();
+
+ // Of the 10 bits for the empty block, we have already sent
+ // (10 - bi_valid) bits. The lookahead for the last real code (before
+ // the EOB of the previous block) was thus at least one plus the length
+ // of the EOB plus what we have just sent of the empty static block.
+ if (1 + last_eob_len + 10 - bi_valid < 9) {
+ send_bits(STATIC_TREES<<1, 3);
+ send_code(END_BLOCK, StaticTree.static_ltree);
+ bi_flush();
+ }
+ last_eob_len = 7;
+ }
+
+
+ // Save the match info and tally the frequency counts. Return true if
+ // the current block must be flushed.
+ boolean _tr_tally (int dist, // distance of matched string
+ int lc // match length-MIN_MATCH or unmatched char (if dist==0)
+ ){
+
+ pending_buf[d_buf+last_lit*2] = (byte)(dist>>>8);
+ pending_buf[d_buf+last_lit*2+1] = (byte)dist;
+
+ pending_buf[l_buf+last_lit] = (byte)lc; last_lit++;
+
+ if (dist == 0) {
+ // lc is the unmatched char
+ dyn_ltree[lc*2]++;
+ }
+ else {
+ matches++;
+ // Here, lc is the match length - MIN_MATCH
+ dist--; // dist = match distance - 1
+ dyn_ltree[(Tree._length_code[lc]+LITERALS+1)*2]++;
+ dyn_dtree[Tree.d_code(dist)*2]++;
+ }
+
+ if ((last_lit & 0x1fff) == 0 && level > 2) {
+ // Compute an upper bound for the compressed length
+ int out_length = last_lit*8;
+ int in_length = strstart - block_start;
+ int dcode;
+ for (dcode = 0; dcode < D_CODES; dcode++) {
+ out_length += (int)dyn_dtree[dcode*2] *
+ (5L+Tree.extra_dbits[dcode]);
+ }
+ out_length >>>= 3;
+ if ((matches < (last_lit/2)) && out_length < in_length/2) return true;
+ }
+
+ return (last_lit == lit_bufsize-1);
+ // We avoid equality with lit_bufsize because of wraparound at 64K
+ // on 16 bit machines and because stored blocks are restricted to
+ // 64K-1 bytes.
+ }
+
+ // Send the block data compressed using the given Huffman trees
+ void compress_block(short[] ltree, short[] dtree){
+ int dist; // distance of matched string
+ int lc; // match length or unmatched char (if dist == 0)
+ int lx = 0; // running index in l_buf
+ int code; // the code to send
+ int extra; // number of extra bits to send
+
+ if (last_lit != 0){
+ do{
+ dist=((pending_buf[d_buf+lx*2]<<8)&0xff00)|
+ (pending_buf[d_buf+lx*2+1]&0xff);
+ lc=(pending_buf[l_buf+lx])&0xff; lx++;
+
+ if(dist == 0){
+ send_code(lc, ltree); // send a literal byte
+ }
+ else{
+ // Here, lc is the match length - MIN_MATCH
+ code = Tree._length_code[lc];
+
+ send_code(code+LITERALS+1, ltree); // send the length code
+ extra = Tree.extra_lbits[code];
+ if(extra != 0){
+ lc -= Tree.base_length[code];
+ send_bits(lc, extra); // send the extra length bits
+ }
+ dist--; // dist is now the match distance - 1
+ code = Tree.d_code(dist);
+
+ send_code(code, dtree); // send the distance code
+ extra = Tree.extra_dbits[code];
+ if (extra != 0) {
+ dist -= Tree.base_dist[code];
+ send_bits(dist, extra); // send the extra distance bits
+ }
+ } // literal or match pair ?
+
+ // Check that the overlay between pending_buf and d_buf+l_buf is ok:
+ }
+ while (lx < last_lit);
+ }
+
+ send_code(END_BLOCK, ltree);
+ last_eob_len = ltree[END_BLOCK*2+1];
+ }
+
+ // Set the data type to ASCII or BINARY, using a crude approximation:
+ // binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
+ // IN assertion: the fields freq of dyn_ltree are set and the total of all
+ // frequencies does not exceed 64K (to fit in an int on 16 bit machines).
+ void set_data_type(){
+ int n = 0;
+ int ascii_freq = 0;
+ int bin_freq = 0;
+ while(n<7){ bin_freq += dyn_ltree[n*2]; n++;}
+ while(n<128){ ascii_freq += dyn_ltree[n*2]; n++;}
+ while(n<LITERALS){ bin_freq += dyn_ltree[n*2]; n++;}
+ data_type=(byte)(bin_freq > (ascii_freq >>> 2) ? Z_BINARY : Z_ASCII);
+ }
+
+ // Flush the bit buffer, keeping at most 7 bits in it.
+ void bi_flush(){
+ if (bi_valid == 16) {
+ put_short(bi_buf);
+ bi_buf=0;
+ bi_valid=0;
+ }
+ else if (bi_valid >= 8) {
+ put_byte((byte)bi_buf);
+ bi_buf>>>=8;
+ bi_valid-=8;
+ }
+ }
+
+ // Flush the bit buffer and align the output on a byte boundary
+ void bi_windup(){
+ if (bi_valid > 8) {
+ put_short(bi_buf);
+ } else if (bi_valid > 0) {
+ put_byte((byte)bi_buf);
+ }
+ bi_buf = 0;
+ bi_valid = 0;
+ }
+
+ // Copy a stored block, storing first the length and its
+ // one's complement if requested.
+ void copy_block(int buf, // the input data
+ int len, // its length
+ boolean header // true if block header must be written
+ ){
+ int index=0;
+ bi_windup(); // align on byte boundary
+ last_eob_len = 8; // enough lookahead for inflate
+
+ if (header) {
+ put_short((short)len);
+ put_short((short)~len);
+ }
+
+ // while(len--!=0) {
+ // put_byte(window[buf+index]);
+ // index++;
+ // }
+ put_byte(window, buf, len);
+ }
+
+ void flush_block_only(boolean eof){
+ _tr_flush_block(block_start>=0 ? block_start : -1,
+ strstart-block_start,
+ eof);
+ block_start=strstart;
+ strm.flush_pending();
+ }
+
+ // Copy without compression as much as possible from the input stream, return
+ // the current block state.
+ // This function does not insert new strings in the dictionary since
+ // uncompressible data is probably not useful. This function is used
+ // only for the level=0 compression option.
+ // NOTE: this function should be optimized to avoid extra copying from
+ // window to pending_buf.
+ int deflate_stored(int flush){
+ // Stored blocks are limited to 0xffff bytes, pending_buf is limited
+ // to pending_buf_size, and each stored block has a 5 byte header:
+
+ int max_block_size = 0xffff;
+ int max_start;
+
+ if(max_block_size > pending_buf_size - 5) {
+ max_block_size = pending_buf_size - 5;
+ }
+
+ // Copy as much as possible from input to output:
+ while(true){
+ // Fill the window as much as possible:
+ if(lookahead<=1){
+ fill_window();
+ if(lookahead==0 && flush==Z_NO_FLUSH) return NeedMore;
+ if(lookahead==0) break; // flush the current block
+ }
+
+ strstart+=lookahead;
+ lookahead=0;
+
+ // Emit a stored block if pending_buf will be full:
+ max_start=block_start+max_block_size;
+ if(strstart==0|| strstart>=max_start) {
+ // strstart == 0 is possible when wraparound on 16-bit machine
+ lookahead = (int)(strstart-max_start);
+ strstart = (int)max_start;
+
+ flush_block_only(false);
+ if(strm.avail_out==0) return NeedMore;
+
+ }
+
+ // Flush if we may have to slide, otherwise block_start may become
+ // negative and the data will be gone:
+ if(strstart-block_start >= w_size-MIN_LOOKAHEAD) {
+ flush_block_only(false);
+ if(strm.avail_out==0) return NeedMore;
+ }
+ }
+
+ flush_block_only(flush == Z_FINISH);
+ if(strm.avail_out==0)
+ return (flush == Z_FINISH) ? FinishStarted : NeedMore;
+
+ return flush == Z_FINISH ? FinishDone : BlockDone;
+ }
+
+ // Send a stored block
+ void _tr_stored_block(int buf, // input block
+ int stored_len, // length of input block
+ boolean eof // true if this is the last block for a file
+ ){
+ send_bits((STORED_BLOCK<<1)+(eof?1:0), 3); // send block type
+ copy_block(buf, stored_len, true); // with header
+ }
+
+ // Determine the best encoding for the current block: dynamic trees, static
+ // trees or store, and output the encoded block to the zip file.
+ void _tr_flush_block(int buf, // input block, or NULL if too old
+ int stored_len, // length of input block
+ boolean eof // true if this is the last block for a file
+ ) {
+ int opt_lenb, static_lenb;// opt_len and static_len in bytes
+ int max_blindex = 0; // index of last bit length code of non zero freq
+
+ // Build the Huffman trees unless a stored block is forced
+ if(level > 0) {
+ // Check if the file is ascii or binary
+ if(data_type == Z_UNKNOWN) set_data_type();
+
+ // Construct the literal and distance trees
+ l_desc.build_tree(this);
+
+ d_desc.build_tree(this);
+
+ // At this point, opt_len and static_len are the total bit lengths of
+ // the compressed block data, excluding the tree representations.
+
+ // Build the bit length tree for the above two trees, and get the index
+ // in bl_order of the last bit length code to send.
+ max_blindex=build_bl_tree();
+
+ // Determine the best encoding. Compute first the block length in bytes
+ opt_lenb=(opt_len+3+7)>>>3;
+ static_lenb=(static_len+3+7)>>>3;
+
+ if(static_lenb<=opt_lenb) opt_lenb=static_lenb;
+ }
+ else {
+ opt_lenb=static_lenb=stored_len+5; // force a stored block
+ }
+
+ if(stored_len+4<=opt_lenb && buf != -1){
+ // 4: two words for the lengths
+ // The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
+ // Otherwise we can't have processed more than WSIZE input bytes since
+ // the last block flush, because compression would have been
+ // successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
+ // transform a block into a stored block.
+ _tr_stored_block(buf, stored_len, eof);
+ }
+ else if(static_lenb == opt_lenb){
+ send_bits((STATIC_TREES<<1)+(eof?1:0), 3);
+ compress_block(StaticTree.static_ltree, StaticTree.static_dtree);
+ }
+ else{
+ send_bits((DYN_TREES<<1)+(eof?1:0), 3);
+ send_all_trees(l_desc.max_code+1, d_desc.max_code+1, max_blindex+1);
+ compress_block(dyn_ltree, dyn_dtree);
+ }
+
+ // The above check is made mod 2^32, for files larger than 512 MB
+ // and uLong implemented on 32 bits.
+
+ init_block();
+
+ if(eof){
+ bi_windup();
+ }
+ }
+
+ // Fill the window when the lookahead becomes insufficient.
+ // Updates strstart and lookahead.
+ //
+ // IN assertion: lookahead < MIN_LOOKAHEAD
+ // OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
+ // At least one byte has been read, or avail_in == 0; reads are
+ // performed for at least two bytes (required for the zip translate_eol
+ // option -- not supported here).
+ void fill_window(){
+ int n, m;
+ int p;
+ int more; // Amount of free space at the end of the window.
+
+ do{
+ more = (window_size-lookahead-strstart);
+
+ // Deal with !@#$% 64K limit:
+ if(more==0 && strstart==0 && lookahead==0){
+ more = w_size;
+ }
+ else if(more==-1) {
+ // Very unlikely, but possible on 16 bit machine if strstart == 0
+ // and lookahead == 1 (input done one byte at time)
+ more--;
+
+ // If the window is almost full and there is insufficient lookahead,
+ // move the upper half to the lower one to make room in the upper half.
+ }
+ else if(strstart >= w_size+ w_size-MIN_LOOKAHEAD) {
+ System.arraycopy(window, w_size, window, 0, w_size);
+ match_start-=w_size;
+ strstart-=w_size; // we now have strstart >= MAX_DIST
+ block_start-=w_size;
+
+ // Slide the hash table (could be avoided with 32 bit values
+ // at the expense of memory usage). We slide even when level == 0
+ // to keep the hash table consistent if we switch back to level > 0
+ // later. (Using level 0 permanently is not an optimal usage of
+ // zlib, so we don't care about this pathological case.)
+
+ n = hash_size;
+ p=n;
+ do {
+ m = (head[--p]&0xffff);
+ head[p]=(m>=w_size ? (short)(m-w_size) : 0);
+ }
+ while (--n != 0);
+
+ n = w_size;
+ p = n;
+ do {
+ m = (prev[--p]&0xffff);
+ prev[p] = (m >= w_size ? (short)(m-w_size) : 0);
+ // If n is not on any hash chain, prev[n] is garbage but
+ // its value will never be used.
+ }
+ while (--n!=0);
+ more += w_size;
+ }
+
+ if (strm.avail_in == 0) return;
+
+ // If there was no sliding:
+ // strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 &&
+ // more == window_size - lookahead - strstart
+ // => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1)
+ // => more >= window_size - 2*WSIZE + 2
+ // In the BIG_MEM or MMAP case (not yet supported),
+ // window_size == input_size + MIN_LOOKAHEAD &&
+ // strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD.
+ // Otherwise, window_size == 2*WSIZE so more >= 2.
+ // If there was sliding, more >= WSIZE. So in all cases, more >= 2.
+
+ n = strm.read_buf(window, strstart + lookahead, more);
+ lookahead += n;
+
+ // Initialize the hash value now that we have some input:
+ if(lookahead >= MIN_MATCH) {
+ ins_h = window[strstart]&0xff;
+ ins_h=(((ins_h)<<hash_shift)^(window[strstart+1]&0xff))&hash_mask;
+ }
+ // If the whole input has less than MIN_MATCH bytes, ins_h is garbage,
+ // but this is not important since only literal bytes will be emitted.
+ }
+ while (lookahead < MIN_LOOKAHEAD && strm.avail_in != 0);
+ }
+
+ // Compress as much as possible from the input stream, return the current
+ // block state.
+ // This function does not perform lazy evaluation of matches and inserts
+ // new strings in the dictionary only for unmatched strings or for short
+ // matches. It is used only for the fast compression options.
+ int deflate_fast(int flush){
+// short hash_head = 0; // head of the hash chain
+ int hash_head = 0; // head of the hash chain
+ boolean bflush; // set if current block must be flushed
+
+ while(true){
+ // Make sure that we always have enough lookahead, except
+ // at the end of the input file. We need MAX_MATCH bytes
+ // for the next match, plus MIN_MATCH bytes to insert the
+ // string following the next match.
+ if(lookahead < MIN_LOOKAHEAD){
+ fill_window();
+ if(lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH){
+ return NeedMore;
+ }
+ if(lookahead == 0) break; // flush the current block
+ }
+
+ // Insert the string window[strstart .. strstart+2] in the
+ // dictionary, and set hash_head to the head of the hash chain:
+ if(lookahead >= MIN_MATCH){
+ ins_h=(((ins_h)<<hash_shift)^(window[(strstart)+(MIN_MATCH-1)]&0xff))&hash_mask;
+
+// prev[strstart&w_mask]=hash_head=head[ins_h];
+ hash_head=(head[ins_h]&0xffff);
+ prev[strstart&w_mask]=head[ins_h];
+ head[ins_h]=(short)strstart;
+ }
+
+ // Find the longest match, discarding those <= prev_length.
+ // At this point we have always match_length < MIN_MATCH
+
+ if(hash_head!=0L &&
+ ((strstart-hash_head)&0xffff) <= w_size-MIN_LOOKAHEAD
+ ){
+ // To simplify the code, we prevent matches with the string
+ // of window index 0 (in particular we have to avoid a match
+ // of the string with itself at the start of the input file).
+ if(strategy != Z_HUFFMAN_ONLY){
+ match_length=longest_match (hash_head);
+ }
+ // longest_match() sets match_start
+ }
+ if(match_length>=MIN_MATCH){
+ // check_match(strstart, match_start, match_length);
+
+ bflush=_tr_tally(strstart-match_start, match_length-MIN_MATCH);
+
+ lookahead -= match_length;
+
+ // Insert new strings in the hash table only if the match length
+ // is not too large. This saves time but degrades compression.
+ if(match_length <= max_lazy_match &&
+ lookahead >= MIN_MATCH) {
+ match_length--; // string at strstart already in hash table
+ do{
+ strstart++;
+
+ ins_h=((ins_h<<hash_shift)^(window[(strstart)+(MIN_MATCH-1)]&0xff))&hash_mask;
+// prev[strstart&w_mask]=hash_head=head[ins_h];
+ hash_head=(head[ins_h]&0xffff);
+ prev[strstart&w_mask]=head[ins_h];
+ head[ins_h]=(short)strstart;
+
+ // strstart never exceeds WSIZE-MAX_MATCH, so there are
+ // always MIN_MATCH bytes ahead.
+ }
+ while (--match_length != 0);
+ strstart++;
+ }
+ else{
+ strstart += match_length;
+ match_length = 0;
+ ins_h = window[strstart]&0xff;
+
+ ins_h=(((ins_h)<<hash_shift)^(window[strstart+1]&0xff))&hash_mask;
+ // If lookahead < MIN_MATCH, ins_h is garbage, but it does not
+ // matter since it will be recomputed at next deflate call.
+ }
+ }
+ else {
+ // No match, output a literal byte
+
+ bflush=_tr_tally(0, window[strstart]&0xff);
+ lookahead--;
+ strstart++;
+ }
+ if (bflush){
+
+ flush_block_only(false);
+ if(strm.avail_out==0) return NeedMore;
+ }
+ }
+
+ flush_block_only(flush == Z_FINISH);
+ if(strm.avail_out==0){
+ if(flush == Z_FINISH) return FinishStarted;
+ else return NeedMore;
+ }
+ return flush==Z_FINISH ? FinishDone : BlockDone;
+ }
+
+ // Same as above, but achieves better compression. We use a lazy
+ // evaluation for matches: a match is finally adopted only if there is
+ // no better match at the next window position.
+ int deflate_slow(int flush){
+// short hash_head = 0; // head of hash chain
+ int hash_head = 0; // head of hash chain
+ boolean bflush; // set if current block must be flushed
+
+ // Process the input block.
+ while(true){
+ // Make sure that we always have enough lookahead, except
+ // at the end of the input file. We need MAX_MATCH bytes
+ // for the next match, plus MIN_MATCH bytes to insert the
+ // string following the next match.
+
+ if (lookahead < MIN_LOOKAHEAD) {
+ fill_window();
+ if(lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {
+ return NeedMore;
+ }
+ if(lookahead == 0) break; // flush the current block
+ }
+
+ // Insert the string window[strstart .. strstart+2] in the
+ // dictionary, and set hash_head to the head of the hash chain:
+
+ if(lookahead >= MIN_MATCH) {
+ ins_h=(((ins_h)<<hash_shift)^(window[(strstart)+(MIN_MATCH-1)]&0xff)) & hash_mask;
+// prev[strstart&w_mask]=hash_head=head[ins_h];
+ hash_head=(head[ins_h]&0xffff);
+ prev[strstart&w_mask]=head[ins_h];
+ head[ins_h]=(short)strstart;
+ }
+
+ // Find the longest match, discarding those <= prev_length.
+ prev_length = match_length; prev_match = match_start;
+ match_length = MIN_MATCH-1;
+
+ if (hash_head != 0 && prev_length < max_lazy_match &&
+ ((strstart-hash_head)&0xffff) <= w_size-MIN_LOOKAHEAD
+ ){
+ // To simplify the code, we prevent matches with the string
+ // of window index 0 (in particular we have to avoid a match
+ // of the string with itself at the start of the input file).
+
+ if(strategy != Z_HUFFMAN_ONLY) {
+ match_length = longest_match(hash_head);
+ }
+ // longest_match() sets match_start
+
+ if (match_length <= 5 && (strategy == Z_FILTERED ||
+ (match_length == MIN_MATCH &&
+ strstart - match_start > 4096))) {
+
+ // If prev_match is also MIN_MATCH, match_start is garbage
+ // but we will ignore the current match anyway.
+ match_length = MIN_MATCH-1;
+ }
+ }
+
+ // If there was a match at the previous step and the current
+ // match is not better, output the previous match:
+ if(prev_length >= MIN_MATCH && match_length <= prev_length) {
+ int max_insert = strstart + lookahead - MIN_MATCH;
+ // Do not insert strings in hash table beyond this.
+
+ // check_match(strstart-1, prev_match, prev_length);
+
+ bflush=_tr_tally(strstart-1-prev_match, prev_length - MIN_MATCH);
+
+ // Insert in hash table all strings up to the end of the match.
+ // strstart-1 and strstart are already inserted. If there is not
+ // enough lookahead, the last two strings are not inserted in
+ // the hash table.
+ lookahead -= prev_length-1;
+ prev_length -= 2;
+ do{
+ if(++strstart <= max_insert) {
+ ins_h=(((ins_h)<<hash_shift)^(window[(strstart)+(MIN_MATCH-1)]&0xff))&hash_mask;
+ //prev[strstart&w_mask]=hash_head=head[ins_h];
+ hash_head=(head[ins_h]&0xffff);
+ prev[strstart&w_mask]=head[ins_h];
+ head[ins_h]=(short)strstart;
+ }
+ }
+ while(--prev_length != 0);
+ match_available = 0;
+ match_length = MIN_MATCH-1;
+ strstart++;
+
+ if (bflush){
+ flush_block_only(false);
+ if(strm.avail_out==0) return NeedMore;
+ }
+ } else if (match_available!=0) {
+
+ // If there was no match at the previous position, output a
+ // single literal. If there was a match but the current match
+ // is longer, truncate the previous match to a single literal.
+
+ bflush=_tr_tally(0, window[strstart-1]&0xff);
+
+ if (bflush) {
+ flush_block_only(false);
+ }
+ strstart++;
+ lookahead--;
+ if(strm.avail_out == 0) return NeedMore;
+ } else {
+ // There is no previous match to compare with, wait for
+ // the next step to decide.
+
+ match_available = 1;
+ strstart++;
+ lookahead--;
+ }
+ }
+
+ if(match_available!=0) {
+ bflush=_tr_tally(0, window[strstart-1]&0xff);
+ match_available = 0;
+ }
+ flush_block_only(flush == Z_FINISH);
+
+ if(strm.avail_out==0){
+ if(flush == Z_FINISH) return FinishStarted;
+ else return NeedMore;
+ }
+
+ return flush == Z_FINISH ? FinishDone : BlockDone;
+ }
+
+ int longest_match(int cur_match){
+ int chain_length = max_chain_length; // max hash chain length
+ int scan = strstart; // current string
+ int match; // matched string
+ int len; // length of current match
+ int best_len = prev_length; // best match length so far
+ int limit = strstart>(w_size-MIN_LOOKAHEAD) ?
+ strstart-(w_size-MIN_LOOKAHEAD) : 0;
+ int nice_match=this.nice_match;
+
+ // Stop when cur_match becomes <= limit. To simplify the code,
+ // we prevent matches with the string of window index 0.
+
+ int wmask = w_mask;
+
+ int strend = strstart + MAX_MATCH;
+ byte scan_end1 = window[scan+best_len-1];
+ byte scan_end = window[scan+best_len];
+
+ // The code is optimized for HASH_BITS >= 8 and MAX_MATCH-2 multiple of 16.
+ // It is easy to get rid of this optimization if necessary.
+
+ // Do not waste too much time if we already have a good match:
+ if (prev_length >= good_match) {
+ chain_length >>= 2;
+ }
+
+ // Do not look for matches beyond the end of the input. This is necessary
+ // to make deflate deterministic.
+ if (nice_match > lookahead) nice_match = lookahead;
+
+ do {
+ match = cur_match;
+
+ // Skip to next match if the match length cannot increase
+ // or if the match length is less than 2:
+ if (window[match+best_len] != scan_end ||
+ window[match+best_len-1] != scan_end1 ||
+ window[match] != window[scan] ||
+ window[++match] != window[scan+1]) continue;
+
+ // The check at best_len-1 can be removed because it will be made
+ // again later. (This heuristic is not always a win.)
+ // It is not necessary to compare scan[2] and match[2] since they
+ // are always equal when the other bytes match, given that
+ // the hash keys are equal and that HASH_BITS >= 8.
+ scan += 2; match++;
+
+ // We check for insufficient lookahead only every 8th comparison;
+ // the 256th check will be made at strstart+258.
+ do {
+ } while (window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ window[++scan] == window[++match] &&
+ scan < strend);
+
+ len = MAX_MATCH - (int)(strend - scan);
+ scan = strend - MAX_MATCH;
+
+ if(len>best_len) {
+ match_start = cur_match;
+ best_len = len;
+ if (len >= nice_match) break;
+ scan_end1 = window[scan+best_len-1];
+ scan_end = window[scan+best_len];
+ }
+
+ } while ((cur_match = (prev[cur_match & wmask]&0xffff)) > limit
+ && --chain_length != 0);
+
+ if (best_len <= lookahead) return best_len;
+ return lookahead;
+ }
+
+ int deflateInit(ZStream strm, int level, int bits){
+ return deflateInit2(strm, level, Z_DEFLATED, bits, DEF_MEM_LEVEL,
+ Z_DEFAULT_STRATEGY);
+ }
+ int deflateInit(ZStream strm, int level){
+ return deflateInit(strm, level, MAX_WBITS);
+ }
+ int deflateInit2(ZStream strm, int level, int method, int windowBits,
+ int memLevel, int strategy){
+ int noheader = 0;
+ // byte[] my_version=ZLIB_VERSION;
+
+ //
+ // if (version == null || version[0] != my_version[0]
+ // || stream_size != sizeof(z_stream)) {
+ // return Z_VERSION_ERROR;
+ // }
+
+ strm.msg = null;
+
+ if (level == Z_DEFAULT_COMPRESSION) level = 6;
+
+ if (windowBits < 0) { // undocumented feature: suppress zlib header
+ noheader = 1;
+ windowBits = -windowBits;
+ }
+
+ if (memLevel < 1 || memLevel > MAX_MEM_LEVEL ||
+ method != Z_DEFLATED ||
+ windowBits < 9 || windowBits > 15 || level < 0 || level > 9 ||
+ strategy < 0 || strategy > Z_HUFFMAN_ONLY) {
+ return Z_STREAM_ERROR;
+ }
+
+ strm.dstate = (Deflate)this;
+
+ this.noheader = noheader;
+ w_bits = windowBits;
+ w_size = 1 << w_bits;
+ w_mask = w_size - 1;
+
+ hash_bits = memLevel + 7;
+ hash_size = 1 << hash_bits;
+ hash_mask = hash_size - 1;
+ hash_shift = ((hash_bits+MIN_MATCH-1)/MIN_MATCH);
+
+ window = new byte[w_size*2];
+ prev = new short[w_size];
+ head = new short[hash_size];
+
+ lit_bufsize = 1 << (memLevel + 6); // 16K elements by default
+
+ // We overlay pending_buf and d_buf+l_buf. This works since the average
+ // output size for (length,distance) codes is <= 24 bits.
+ pending_buf = new byte[lit_bufsize*4];
+ pending_buf_size = lit_bufsize*4;
+
+ d_buf = lit_bufsize/2;
+ l_buf = (1+2)*lit_bufsize;
+
+ this.level = level;
+
+//System.out.println("level="+level);
+
+ this.strategy = strategy;
+ this.method = (byte)method;
+
+ return deflateReset(strm);
+ }
+
+ int deflateReset(ZStream strm){
+ strm.total_in = strm.total_out = 0;
+ strm.msg = null; //
+ strm.data_type = Z_UNKNOWN;
+
+ pending = 0;
+ pending_out = 0;
+
+ if(noheader < 0) {
+ noheader = 0; // was set to -1 by deflate(..., Z_FINISH);
+ }
+ status = (noheader!=0) ? BUSY_STATE : INIT_STATE;
+ strm.adler=strm._adler.adler32(0, null, 0, 0);
+
+ last_flush = Z_NO_FLUSH;
+
+ tr_init();
+ lm_init();
+ return Z_OK;
+ }
+
+ int deflateEnd(){
+ if(status!=INIT_STATE && status!=BUSY_STATE && status!=FINISH_STATE){
+ return Z_STREAM_ERROR;
+ }
+ // Deallocate in reverse order of allocations:
+ pending_buf=null;
+ head=null;
+ prev=null;
+ window=null;
+ // free
+ // dstate=null;
+ return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;
+ }
+
+ int deflateParams(ZStream strm, int _level, int _strategy){
+ int err=Z_OK;
+
+ if(_level == Z_DEFAULT_COMPRESSION){
+ _level = 6;
+ }
+ if(_level < 0 || _level > 9 ||
+ _strategy < 0 || _strategy > Z_HUFFMAN_ONLY) {
+ return Z_STREAM_ERROR;
+ }
+
+ if(config_table[level].func!=config_table[_level].func &&
+ strm.total_in != 0) {
+ // Flush the last buffer:
+ err = strm.deflate(Z_PARTIAL_FLUSH);
+ }
+
+ if(level != _level) {
+ level = _level;
+ max_lazy_match = config_table[level].max_lazy;
+ good_match = config_table[level].good_length;
+ nice_match = config_table[level].nice_length;
+ max_chain_length = config_table[level].max_chain;
+ }
+ strategy = _strategy;
+ return err;
+ }
+
+ int deflateSetDictionary (ZStream strm, byte[] dictionary, int dictLength){
+ int length = dictLength;
+ int index=0;
+
+ if(dictionary == null || status != INIT_STATE)
+ return Z_STREAM_ERROR;
+
+ strm.adler=strm._adler.adler32(strm.adler, dictionary, 0, dictLength);
+
+ if(length < MIN_MATCH) return Z_OK;
+ if(length > w_size-MIN_LOOKAHEAD){
+ length = w_size-MIN_LOOKAHEAD;
+ index=dictLength-length; // use the tail of the dictionary
+ }
+ System.arraycopy(dictionary, index, window, 0, length);
+ strstart = length;
+ block_start = length;
+
+ // Insert all strings in the hash table (except for the last two bytes).
+ // s->lookahead stays null, so s->ins_h will be recomputed at the next
+ // call of fill_window.
+
+ ins_h = window[0]&0xff;
+ ins_h=(((ins_h)<<hash_shift)^(window[1]&0xff))&hash_mask;
+
+ for(int n=0; n<=length-MIN_MATCH; n++){
+ ins_h=(((ins_h)<<hash_shift)^(window[(n)+(MIN_MATCH-1)]&0xff))&hash_mask;
+ prev[n&w_mask]=head[ins_h];
+ head[ins_h]=(short)n;
+ }
+ return Z_OK;
+ }
+
+ int deflate(ZStream strm, int flush){
+ int old_flush;
+
+ if(flush>Z_FINISH || flush<0){
+ return Z_STREAM_ERROR;
+ }
+
+ if(strm.next_out == null ||
+ (strm.next_in == null && strm.avail_in != 0) ||
+ (status == FINISH_STATE && flush != Z_FINISH)) {
+ strm.msg=z_errmsg[Z_NEED_DICT-(Z_STREAM_ERROR)];
+ return Z_STREAM_ERROR;
+ }
+ if(strm.avail_out == 0){
+ strm.msg=z_errmsg[Z_NEED_DICT-(Z_BUF_ERROR)];
+ return Z_BUF_ERROR;
+ }
+
+ this.strm = strm; // just in case
+ old_flush = last_flush;
+ last_flush = flush;
+
+ // Write the zlib header
+ if(status == INIT_STATE) {
+ int header = (Z_DEFLATED+((w_bits-8)<<4))<<8;
+ int level_flags=((level-1)&0xff)>>1;
+
+ if(level_flags>3) level_flags=3;
+ header |= (level_flags<<6);
+ if(strstart!=0) header |= PRESET_DICT;
+ header+=31-(header % 31);
+
+ status=BUSY_STATE;
+ putShortMSB(header);
+
+
+ // Save the adler32 of the preset dictionary:
+ if(strstart!=0){
+ putShortMSB((int)(strm.adler>>>16));
+ putShortMSB((int)(strm.adler&0xffff));
+ }
+ strm.adler=strm._adler.adler32(0, null, 0, 0);
+ }
+
+ // Flush as much pending output as possible
+ if(pending != 0) {
+ strm.flush_pending();
+ if(strm.avail_out == 0) {
+ //System.out.println(" avail_out==0");
+ // Since avail_out is 0, deflate will be called again with
+ // more output space, but possibly with both pending and
+ // avail_in equal to zero. There won't be anything to do,
+ // but this is not an error situation so make sure we
+ // return OK instead of BUF_ERROR at next call of deflate:
+ last_flush = -1;
+ return Z_OK;
+ }
+
+ // Make sure there is something to do and avoid duplicate consecutive
+ // flushes. For repeated and useless calls with Z_FINISH, we keep
+ // returning Z_STREAM_END instead of Z_BUFF_ERROR.
+ }
+ else if(strm.avail_in==0 && flush <= old_flush &&
+ flush != Z_FINISH) {
+ strm.msg=z_errmsg[Z_NEED_DICT-(Z_BUF_ERROR)];
+ return Z_BUF_ERROR;
+ }
+
+ // User must not provide more input after the first FINISH:
+ if(status == FINISH_STATE && strm.avail_in != 0) {
+ strm.msg=z_errmsg[Z_NEED_DICT-(Z_BUF_ERROR)];
+ return Z_BUF_ERROR;
+ }
+
+ // Start a new block or continue the current one.
+ if(strm.avail_in!=0 || lookahead!=0 ||
+ (flush != Z_NO_FLUSH && status != FINISH_STATE)) {
+ int bstate=-1;
+ switch(config_table[level].func){
+ case STORED:
+ bstate = deflate_stored(flush);
+ break;
+ case FAST:
+ bstate = deflate_fast(flush);
+ break;
+ case SLOW:
+ bstate = deflate_slow(flush);
+ break;
+ default:
+ }
+
+ if (bstate==FinishStarted || bstate==FinishDone) {
+ status = FINISH_STATE;
+ }
+ if (bstate==NeedMore || bstate==FinishStarted) {
+ if(strm.avail_out == 0) {
+ last_flush = -1; // avoid BUF_ERROR next call, see above
+ }
+ return Z_OK;
+ // If flush != Z_NO_FLUSH && avail_out == 0, the next call
+ // of deflate should use the same flush parameter to make sure
+ // that the flush is complete. So we don't have to output an
+ // empty block here, this will be done at next call. This also
+ // ensures that for a very small output buffer, we emit at most
+ // one empty block.
+ }
+
+ if (bstate==BlockDone) {
+ if(flush == Z_PARTIAL_FLUSH) {
+ _tr_align();
+ }
+ else { // FULL_FLUSH or SYNC_FLUSH
+ _tr_stored_block(0, 0, false);
+ // For a full flush, this empty block will be recognized
+ // as a special marker by inflate_sync().
+ if(flush == Z_FULL_FLUSH) {
+ //state.head[s.hash_size-1]=0;
+ for(int i=0; i<hash_size/*-1*/; i++) // forget history
+ head[i]=0;
+ }
+ }
+ strm.flush_pending();
+ if(strm.avail_out == 0) {
+ last_flush = -1; // avoid BUF_ERROR at next call, see above
+ return Z_OK;
+ }
+ }
+ }
+
+ if(flush!=Z_FINISH) return Z_OK;
+ if(noheader!=0) return Z_STREAM_END;
+
+ // Write the zlib trailer (adler32)
+ putShortMSB((int)(strm.adler>>>16));
+ putShortMSB((int)(strm.adler&0xffff));
+ strm.flush_pending();
+
+ // If avail_out is zero, the application will call deflate again
+ // to flush the rest.
+ noheader = -1; // write the trailer only once!
+ return pending != 0 ? Z_OK : Z_STREAM_END;
+ }
+}