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Diffstat (limited to 'Crypto/src/util/zlib/Deflate.cs')
| -rw-r--r-- | Crypto/src/util/zlib/Deflate.cs | 1640 |
1 files changed, 1640 insertions, 0 deletions
diff --git a/Crypto/src/util/zlib/Deflate.cs b/Crypto/src/util/zlib/Deflate.cs new file mode 100644 index 000000000..ca0430939 --- /dev/null +++ b/Crypto/src/util/zlib/Deflate.cs @@ -0,0 +1,1640 @@ +using System; +/* + * $Id: Deflate.cs,v 1.2 2008-05-10 09:35:40 bouncy Exp $ + * +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. + */ + +namespace Org.BouncyCastle.Utilities.Zlib { + + public sealed class Deflate{ + + private const int MAX_MEM_LEVEL=9; + + private const int Z_DEFAULT_COMPRESSION=-1; + + private const int MAX_WBITS=15; // 32K LZ77 window + private const int DEF_MEM_LEVEL=8; + + internal class Config{ + internal int good_length; // reduce lazy search above this match length + internal int max_lazy; // do not perform lazy search above this match length + internal int nice_length; // quit search above this match length + internal int max_chain; + internal int func; + internal 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; + } + } + + private const int STORED=0; + private const int FAST=1; + private const int SLOW=2; + private static readonly Config[] config_table; + + static Deflate(){ + 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); + } + + private static readonly 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 + private const int NeedMore=0; + + // block flush performed + private const int BlockDone=1; + + // finish started, need only more output at next deflate + private const int FinishStarted=2; + + // finish done, accept no more input or output + private const int FinishDone=3; + + // preset dictionary flag in zlib header + private const int PRESET_DICT=0x20; + + private const int Z_FILTERED=1; + private const int Z_HUFFMAN_ONLY=2; + private const int Z_DEFAULT_STRATEGY=0; + + private const int Z_NO_FLUSH=0; + private const int Z_PARTIAL_FLUSH=1; + private const int Z_SYNC_FLUSH=2; + private const int Z_FULL_FLUSH=3; + private const int Z_FINISH=4; + + private const int Z_OK=0; + private const int Z_STREAM_END=1; + private const int Z_NEED_DICT=2; + private const int Z_ERRNO=-1; + private const int Z_STREAM_ERROR=-2; + private const int Z_DATA_ERROR=-3; + private const int Z_MEM_ERROR=-4; + private const int Z_BUF_ERROR=-5; + private const int Z_VERSION_ERROR=-6; + + private const int INIT_STATE=42; + private const int BUSY_STATE=113; + private const int FINISH_STATE=666; + + // The deflate compression method + private const int Z_DEFLATED=8; + + private const int STORED_BLOCK=0; + private const int STATIC_TREES=1; + private const int DYN_TREES=2; + + // The three kinds of block type + private const int Z_BINARY=0; + private const int Z_ASCII=1; + private const int Z_UNKNOWN=2; + + private const int Buf_size=8*2; + + // repeat previous bit length 3-6 times (2 bits of repeat count) + private const int REP_3_6=16; + + // repeat a zero length 3-10 times (3 bits of repeat count) + private const int REPZ_3_10=17; + + // repeat a zero length 11-138 times (7 bits of repeat count) + private const int REPZ_11_138=18; + + private const int MIN_MATCH=3; + private const int MAX_MATCH=258; + private const int MIN_LOOKAHEAD=(MAX_MATCH+MIN_MATCH+1); + + private const int MAX_BITS=15; + private const int D_CODES=30; + private const int BL_CODES=19; + private const int LENGTH_CODES=29; + private const int LITERALS=256; + private const int L_CODES=(LITERALS+1+LENGTH_CODES); + private const int HEAP_SIZE=(2*L_CODES+1); + + private const int END_BLOCK=256; + + internal ZStream strm; // pointer back to this zlib stream + internal int status; // as the name implies + internal byte[] pending_buf; // output still pending + internal int pending_buf_size; // size of pending_buf + internal int pending_out; // next pending byte to output to the stream + internal int pending; // nb of bytes in the pending buffer + internal int noheader; // suppress zlib header and adler32 + internal byte data_type; // UNKNOWN, BINARY or ASCII + internal byte method; // STORED (for zip only) or DEFLATED + internal int last_flush; // value of flush param for previous deflate call + + internal int w_size; // LZ77 window size (32K by default) + internal int w_bits; // log2(w_size) (8..16) + internal int w_mask; // w_size - 1 + + internal 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. + + internal int window_size; + // Actual size of window: 2*wSize, except when the user input buffer + // is directly used as sliding window. + + internal 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. + + internal short[] head; // Heads of the hash chains or NIL. + + internal int ins_h; // hash index of string to be inserted + internal int hash_size; // number of elements in hash table + internal int hash_bits; // log2(hash_size) + internal 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 + internal int hash_shift; + + // Window position at the beginning of the current output block. Gets + // negative when the window is moved backwards. + + internal int block_start; + + internal int match_length; // length of best match + internal int prev_match; // previous match + internal int match_available; // set if previous match exists + internal int strstart; // start of string to insert + internal int match_start; // start of matching string + internal 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. + internal 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. + internal 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. + internal 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. + + internal int level; // compression level (1..9) + internal int strategy; // favor or force Huffman coding + + // Use a faster search when the previous match is longer than this + internal int good_match; + + // Stop searching when current match exceeds this + internal int nice_match; + + internal short[] dyn_ltree; // literal and length tree + internal short[] dyn_dtree; // distance tree + internal short[] bl_tree; // Huffman tree for bit lengths + + internal Tree l_desc=new Tree(); // desc for literal tree + internal Tree d_desc=new Tree(); // desc for distance tree + internal Tree bl_desc=new Tree(); // desc for bit length tree + + // number of codes at each bit length for an optimal tree + internal short[] bl_count=new short[MAX_BITS+1]; + + // heap used to build the Huffman trees + internal int[] heap=new int[2*L_CODES+1]; + + internal int heap_len; // number of elements in the heap + internal 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 + internal byte[] depth=new byte[2*L_CODES+1]; + + internal 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 + internal int lit_bufsize; + + internal 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. + + internal int d_buf; // index of pendig_buf + + internal int opt_len; // bit length of current block with optimal trees + internal int static_len; // bit length of current block with static trees + internal int matches; // number of string matches in current block + internal int last_eob_len; // bit length of EOB code for last block + + // Output buffer. bits are inserted starting at the bottom (least + // significant bits). + internal uint bi_buf; + + // Number of valid bits in bi_buf. All bits above the last valid bit + // are always zero. + internal int bi_valid; + + internal 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 + } + + internal 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. + internal 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(); + } + + internal 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). + internal 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; + } + + internal static bool 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. + internal 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] = -1; // 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] += (short)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. + internal 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. + internal 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. + internal 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. + internal void put_byte(byte[] p, int start, int len){ + System.Array.Copy(p, start, pending_buf, pending, len); + pending+=len; + } + + internal void put_byte(byte c){ + pending_buf[pending++]=c; + } + internal void put_short(int w) { + pending_buf[pending++]=(byte)(w/*&0xff*/); + pending_buf[pending++]=(byte)(w>>8); + } + internal void putShortMSB(int b){ + pending_buf[pending++]=(byte)(b>>8); + pending_buf[pending++]=(byte)(b/*&0xff*/); + } + + internal void send_code(int c, short[] tree){ + int c2=c*2; + send_bits((tree[c2]&0xffff), (tree[c2+1]&0xffff)); + } + + internal void send_bits(int val, int length){ + if (bi_valid > Buf_size - length) { + bi_buf |= (uint)(val << bi_valid); + pending_buf[pending++]=(byte)(bi_buf/*&0xff*/); + pending_buf[pending++]=(byte)(bi_buf>>8); + bi_buf = ((uint)val) >> (Buf_size - bi_valid); + bi_valid += length - Buf_size; + } else { + bi_buf |= (uint)(val << bi_valid); + bi_valid += length; + } +// int len = length; +// if (bi_valid > (int)Buf_size - len) { +// int val = value; +// // bi_buf |= (val << bi_valid); +// bi_buf = (short)((ushort)bi_buf | (ushort)((val << bi_valid)&0xffff)); +// put_short(bi_buf); +// bi_buf = (short)(((uint)val) >> (Buf_size - bi_valid)); +// bi_valid += len - Buf_size; +// } else { +// // bi_buf |= (value) << bi_valid; +// bi_buf = (short)((ushort)bi_buf | (ushort)(((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. + internal 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. + internal bool _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)((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 + internal 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). + internal 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. + internal void bi_flush(){ + if (bi_valid == 16) { + pending_buf[pending++]=(byte)(bi_buf/*&0xff*/); + pending_buf[pending++]=(byte)(bi_buf>>8); + bi_buf=0; + bi_valid=0; + } + else if (bi_valid >= 8) { + pending_buf[pending++]=(byte)(bi_buf); + bi_buf>>=8; + bi_buf &= 0x00ff; + bi_valid-=8; + } + } + + // Flush the bit buffer and align the output on a byte boundary + internal void bi_windup(){ + if (bi_valid > 8) { + pending_buf[pending++]=(byte)(bi_buf); + pending_buf[pending++]=(byte)(bi_buf>>8); + } else if (bi_valid > 0) { + pending_buf[pending++]=(byte)(bi_buf); + } + bi_buf = 0; + bi_valid = 0; + } + + // Copy a stored block, storing first the length and its + // one's complement if requested. + internal void copy_block(int buf, // the input data + int len, // its length + bool 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); + } + + internal void flush_block_only(bool 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. + internal 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 + internal void _tr_stored_block(int buf, // input block + int stored_len, // length of input block + bool 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. + internal void _tr_flush_block(int buf, // input block, or NULL if too old + int stored_len, // length of input block + bool 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). + internal 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.Array.Copy(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]=(short)(m>=w_size ? (m-w_size) : 0); + } + while (--n != 0); + + n = w_size; + p = n; + do { + m = (prev[--p]&0xffff); + prev[p] = (short)(m >= w_size ? (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. + internal int deflate_fast(int flush){ + // short hash_head = 0; // head of the hash chain + int hash_head = 0; // head of the hash chain + bool 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. + internal int deflate_slow(int flush){ + // short hash_head = 0; // head of hash chain + int hash_head = 0; // head of hash chain + bool 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; + } + + internal 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; + } + + internal int deflateInit(ZStream strm, int level, int bits){ + return deflateInit2(strm, level, Z_DEFLATED, bits, DEF_MEM_LEVEL, + Z_DEFAULT_STRATEGY); + } + internal int deflateInit(ZStream strm, int level){ + return deflateInit(strm, level, MAX_WBITS); + } + internal 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); + } + + internal 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; + } + + internal 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; + } + + internal 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; + } + + internal 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.Array.Copy(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; + } + + internal 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: + break; + } + + 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; + } + } +} \ No newline at end of file |