510Connectbot: src/com/jcraft/jzlib/Deflate.java comparison

comparison src/com/jcraft/jzlib/Deflate.java @ 0:0ce5cc452d02

initial version

author	Carl Byington <carl@five-ten-sg.com>
date	Thu, 22 May 2014 10:41:19 -0700
parents
children	46c2115ae1c8

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--1:000000000000
+:0ce5cc452d02
+/* -*-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;
+}
+}

Mercurial > 510Connectbot

comparison src/com/jcraft/jzlib/Deflate.java @ 0:0ce5cc452d02