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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([email protected]) and Mark Adler([email protected])
* 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= 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 (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)<= MIN_MATCH){
ins_h=(((ins_h)<=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<= MIN_MATCH) {
ins_h=(((ins_h)< 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)<(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)<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) {
// CMF: 0-3 CM, 4-7 CINFO (one byte)
int header = (Z_DEFLATED+((w_bits-8)<<4))<<8; //cmf: 1000 0111
// FLG: 0-4 FCHECK, 5 FDICT, 6-7 FLEVEL (one byte)
int level_flags=((level-1)&0xff)>>1; //flevel: 0 - 3, 2 for default algorithm
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: //default FLEVEL
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>>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;
}
}
