/* deflate.c -- compress data using the deflation algorithm

 * Copyright (C) 1995-2005 Jean-loup Gailly.

 * For conditions of distribution and use, see copyright notice in zlib.h

 */



/*

 *  ALGORITHM

 *

 *      The "deflation" process depends on being able to identify portions

 *      of the input text which are identical to earlier input (within a

 *      sliding window trailing behind the input currently being processed).

 *

 *      The most straightforward technique turns out to be the fastest for

 *      most input files: try all possible matches and select the longest.

 *      The key feature of this algorithm is that insertions into the string

 *      dictionary are very simple and thus fast, and deletions are avoided

 *      completely. Insertions are performed at each input character, whereas

 *      string matches are performed only when the previous match ends. So it

 *      is preferable to spend more time in matches to allow very fast string

 *      insertions and avoid deletions. The matching algorithm for small

 *      strings is inspired from that of Rabin & Karp. A brute force approach

 *      is used to find longer strings when a small match has been found.

 *      A similar algorithm is used in comic (by Jan-Mark Wams) and freeze

 *      (by Leonid Broukhis).

 *         A previous version of this file used a more sophisticated algorithm

 *      (by Fiala and Greene) which is guaranteed to run in linear amortized

 *      time, but has a larger average cost, uses more memory and is patented.

 *      However the F&G algorithm may be faster for some highly redundant

 *      files if the parameter max_chain_length (described below) is too large.

 *

 *  ACKNOWLEDGEMENTS

 *

 *      The idea of lazy evaluation of matches is due to Jan-Mark Wams, and

 *      I found it in 'freeze' written by Leonid Broukhis.

 *      Thanks to many people for bug reports and testing.

 *

 *  REFERENCES

 *

 *      Deutsch, L.P.,"DEFLATE Compressed Data Format Specification".

 *      Available in http://www.ietf.org/rfc/rfc1951.txt

 *

 *      A description of the Rabin and Karp algorithm is given in the book

 *         "Algorithms" by R. Sedgewick, Addison-Wesley, p252.

 *

 *      Fiala,E.R., and Greene,D.H.

 *         Data Compression with Finite Windows, Comm.ACM, 32,4 (1989) 490-595

 *

 */



/* @(#) $Id$ */



#include "edgezlib_deflate.h"



const char deflate_copyright[] =

   " deflate 1.2.3 Copyright 1995-2005 Jean-loup Gailly ";

/*

  If you use the zlib library in a product, an acknowledgment is welcome

  in the documentation of your product. If for some reason you cannot

  include such an acknowledgment, I would appreciate that you keep this

  copyright string in the executable of your product.

 */



/* ===========================================================================

 *  Function prototypes.

 */

typedef enum {

    need_more,      /* block not completed, need more input or more output */

    block_done,     /* block flush performed */

    finish_started, /* finish started, need only more output at next deflate */

    finish_done     /* finish done, accept no more input or output */

} block_state;



typedef block_state (*compress_func) OF((deflate_state *s, int flush));

/* Compression function. Returns the block state after the call. */



local void fill_window    OF((deflate_state *s));

local block_state deflate_stored OF((deflate_state *s, int flush));

local block_state deflate_fast   OF((deflate_state *s, int flush));

#ifndef FASTEST

local block_state deflate_slow   OF((deflate_state *s, int flush));

#endif

local void lm_init        OF((deflate_state *s));

local void putShortMSB    OF((deflate_state *s, uInt b));

local void flush_pending  OF((z_streamp strm));

local int read_buf        OF((z_streamp strm, Bytef *buf, unsigned size));

#ifndef FASTEST

#ifdef ASMV

      void match_init OF((void)); /* asm code initialization */

      uInt longest_match_original  OF((deflate_state *s, IPos cur_match));

#else

      uInt longest_match_original  OF((deflate_state *s, IPos cur_match));

#endif

#endif



uInt longest_match_optimized_c  OF((deflate_state *s, IPos cur_match));

extern uInt _edgeZlib_longest_match_spu_asm( deflate_state* s, IPos cur_match );



//Choose which version we want to call

//#define longest_match longest_match_original

//#define longest_match longest_match_optimized_c

#define longest_match _edgeZlib_longest_match_spu_asm



local uInt longest_match_fast OF((deflate_state *s, IPos cur_match));



#ifdef DEBUG

local  void check_match OF((deflate_state *s, IPos start, IPos match,

                            int length));

#endif



/* ===========================================================================

 * Local data

 */



#define NIL 0

/* Tail of hash chains */



#ifndef TOO_FAR

#  define TOO_FAR 4096

#endif

/* Matches of length 3 are discarded if their distance exceeds TOO_FAR */



#define MIN_LOOKAHEAD (MAX_MATCH+MIN_MATCH+1)

/* Minimum amount of lookahead, except at the end of the input file.

 * See deflate.c for comments about the MIN_MATCH+1.

 */



//To avoid having to have compile time initialization of function pointers in the data

// table below, instead we use enums for the function IDs.

typedef enum EdgeZlibDeflateFuncChoice

{

	kFuncChoiceDeflateSlow,

	kFuncChoiceDeflateFast,

	kFuncChoiceDeflateStored

} EdgeZlibDeflateFuncChoice;



/* Values for max_lazy_match, good_match and max_chain_length, depending on

 * the desired pack level (0..9). The values given below have been tuned to

 * exclude worst case performance for pathological files. Better values may be

 * found for specific files.

 */

typedef struct config_s {

   ush good_length; /* reduce lazy search above this match length */

   ush max_lazy;    /* do not perform lazy search above this match length */

   ush nice_length; /* quit search above this match length */

   ush max_chain;

   EdgeZlibDeflateFuncChoice funcChoice;

} config;



//Note that for PIC this table could have resulted in compile-time pointers needing to be resolved.

//For that reason we've changed it to enums rather than function pointers.

#ifdef FASTEST

local const config configuration_table[2] = {

/*      good lazy nice chain */

/* 0 */ {0,    0,  0,    0, kFuncChoiceDeflateStored},  /* store only */

/* 1 */ {4,    4,  8,    4, kFuncChoiceDeflateFast}}; /* max speed, no lazy matches */

#else

local const config configuration_table[10] = {

/*      good lazy nice chain */

/* 0 */ {0,    0,  0,    0, kFuncChoiceDeflateStored},  /* store only */

/* 1 */ {4,    4,  8,    4, kFuncChoiceDeflateFast}, /* max speed, no lazy matches */

/* 2 */ {4,    5, 16,    8, kFuncChoiceDeflateFast},

/* 3 */ {4,    6, 32,   32, kFuncChoiceDeflateFast},



/* 4 */ {4,    4, 16,   16, kFuncChoiceDeflateSlow},  /* lazy matches */

/* 5 */ {8,   16, 32,   32, kFuncChoiceDeflateSlow},

/* 6 */ {8,   16, 128, 128, kFuncChoiceDeflateSlow},

/* 7 */ {8,   32, 128, 256, kFuncChoiceDeflateSlow},

/* 8 */ {32, 128, 258, 1024, kFuncChoiceDeflateSlow},

/* 9 */ {32, 258, 258, 4096, kFuncChoiceDeflateSlow}}; /* max compression */

#endif



/* Note: the deflate() code requires max_lazy >= MIN_MATCH and max_chain >= 4

 * For deflate_fast() (levels <= 3) good is ignored and lazy has a different

 * meaning.

 */



#define EQUAL 0

/* result of memcmp for equal strings */



#ifndef NO_DUMMY_DECL

struct static_tree_desc_s {int dummy;}; /* for buggy compilers */

#endif



/* ===========================================================================

 * Update a hash value with the given input byte

 * IN  assertion: all calls to to UPDATE_HASH are made with consecutive

 *    input characters, so that a running hash key can be computed from the

 *    previous key instead of complete recalculation each time.

 */

#define UPDATE_HASH(s,h,c) (h = (((h)<<s->hash_shift) ^ (c)) & s->hash_mask)





/* ===========================================================================

 * Insert string str in the dictionary and set match_head to the previous head

 * of the hash chain (the most recent string with same hash key). Return

 * the previous length of the hash chain.

 * If this file is compiled with -DFASTEST, the compression level is forced

 * to 1, and no hash chains are maintained.

 * IN  assertion: all calls to to INSERT_STRING are made with consecutive

 *    input characters and the first MIN_MATCH bytes of str are valid

 *    (except for the last MIN_MATCH-1 bytes of the input file).

 */

#ifdef FASTEST

#define INSERT_STRING(s, str, match_head) \

   (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \

    match_head = s->head[s->ins_h], \

    s->head[s->ins_h] = (Pos)(str))

#else

#define INSERT_STRING(s, str, match_head) \

   (UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \

    match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \

    s->head[s->ins_h] = (Pos)(str))

#endif



/* ===========================================================================

 * Initialize the hash table (avoiding 64K overflow for 16 bit systems).

 * prev[] will be initialized on the fly.

 */

#define CLEAR_HASH(s) \

    s->head[s->hash_size-1] = NIL; \

    zmemzero((Bytef *)s->head, (unsigned)(s->hash_size-1)*sizeof(*s->head));



/* ========================================================================= */



#define PREDICT_LIKELY( cond )	__builtin_expect( ( cond ), 1 )

#define PREDICT_UNLIKELY( cond )	__builtin_expect( ( cond ), 0 )



#define MY_MIN( a, b ) ((a) < (b) ? (a) : (b))



#define COUNT_HITS()	do { } while ( 0 )



/* ========================================================================= */

int ZEXPORT deflateInit_(strm, level, version, stream_size)

    z_streamp strm;

    int level;

    const char *version;

    int stream_size;

{

    return deflateInit2_(strm, level, Z_DEFLATED, MAX_WBITS, DEF_MEM_LEVEL,

                         Z_DEFAULT_STRATEGY, version, stream_size);

    /* To do: ignore strm->next_in if we use it as window */

}



/* ========================================================================= */

int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy,

                  version, stream_size)

    z_streamp strm;

    int  level;

    int  method;

    int  windowBits;

    int  memLevel;

    int  strategy;

    const char *version;

    int stream_size;

{

    deflate_state *s;

    int wrap = 1;

    static const char my_version[] = ZLIB_VERSION;



    ushf *overlay;

    /* We overlay pending_buf and d_buf+l_buf. This works since the average

     * output size for (length,distance) codes is <= 24 bits.

     */



    if (version == Z_NULL || version[0] != my_version[0] ||

        stream_size != sizeof(z_stream)) {

        return Z_VERSION_ERROR;

    }

    if (strm == Z_NULL) return Z_STREAM_ERROR;



    strm->msg = Z_NULL;



//    if (strm->zalloc == (alloc_func)0) {

//        strm->zalloc = zcalloc;

//        strm->opaque = (voidpf)0;

//    }

//    if (strm->zfree == (free_func)0) strm->zfree = zcfree;



#ifdef FASTEST

    if (level != 0) level = 1;

#else

    if (level == Z_DEFAULT_COMPRESSION) level = 6;

#endif



    if (windowBits < 0) { /* suppress zlib wrapper */

        wrap = 0;

        windowBits = -windowBits;

    }

#ifdef GZIP

    else if (windowBits > 15) {

        wrap = 2;       /* write gzip wrapper instead */

        windowBits -= 16;

    }

#endif

    if (memLevel < 1 || memLevel > MAX_MEM_LEVEL || method != Z_DEFLATED ||

        windowBits < 8 || windowBits > 15 || level < 0 || level > 9 ||

        strategy < 0 || strategy > Z_FIXED) {

        return Z_STREAM_ERROR;

    }

    if (windowBits == 8) windowBits = 9;  /* until 256-byte window bug fixed */



	//s = (deflate_state *) ZALLOC(strm, 1, sizeof(deflate_state));

	static deflate_state	s_state_init2;

	s = &s_state_init2;



    if (s == Z_NULL) return Z_MEM_ERROR;

    strm->state = (struct internal_state FAR *)s;

    s->strm = strm;



    s->wrap = wrap;

    s->gzhead = Z_NULL;

    s->w_bits = windowBits;

    s->w_size = 1 << s->w_bits;

    s->w_mask = s->w_size - 1;



    s->hash_bits = memLevel + 7;

    s->hash_size = 1 << s->hash_bits;

    s->hash_mask = s->hash_size - 1;

    s->hash_shift =  ((s->hash_bits+MIN_MATCH-1)/MIN_MATCH);



	//windowBits must not be greater than this value or else we'd overflow

	//our statically allocated buffers below.

	if ( windowBits > MAX_WBITS )

		return Z_STREAM_ERROR;



	//s->window = (Bytef *) ZALLOC(strm, s->w_size, 2*sizeof(Byte));

	//s->prev   = (Posf *)  ZALLOC(strm, s->w_size, sizeof(Pos));

	//s->head   = (Posf *)  ZALLOC(strm, s->hash_size, sizeof(Pos));

	static Byte	s_window_init2	[ (1 << MAX_WBITS) * 2 ];

	static Pos	s_prev_init2	[ (1 << MAX_WBITS) * sizeof(Pos) / sizeof(Pos) ];

	static Pos	s_head_init2	[ (1 << (MAX_MEM_LEVEL+7)) * sizeof(Pos) / sizeof(Pos) ];

	s->window		= &s_window_init2[0];

	s->prev			= &s_prev_init2[0];

	s->head			= &s_head_init2[0];



    s->lit_bufsize = 1 << (memLevel + 6); /* 16K elements by default */



	//overlay = (ushf *) ZALLOC(strm, s->lit_bufsize, sizeof(ush)+2);

	static ush	s_overlay_init2	[ (1 << (MAX_MEM_LEVEL+6)) * (sizeof(ush)+2) / sizeof(ush) ];

	overlay = &s_overlay_init2[0];



    s->pending_buf = (uchf *) overlay;

    s->pending_buf_size = (ulg)s->lit_bufsize * (sizeof(ush)+2L);



    if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL ||

        s->pending_buf == Z_NULL) {

        s->status = FINISH_STATE;

        strm->msg = (char*)ERR_MSG(Z_MEM_ERROR);

        deflateEnd (strm);

        return Z_MEM_ERROR;

    }

    s->d_buf = overlay + s->lit_bufsize/sizeof(ush);

    s->l_buf = s->pending_buf + (1+sizeof(ush))*s->lit_bufsize;



    s->level = level;

    s->strategy = strategy;

    s->method = (Byte)method;



    return deflateReset(strm);

}



/* ========================================================================= */

int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength)

    z_streamp strm;

    const Bytef *dictionary;

    uInt  dictLength;

{

    deflate_state *s;

    uInt length = dictLength;

    uInt n;

    IPos hash_head = 0;



    if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL ||

        strm->state->wrap == 2 ||

        (strm->state->wrap == 1 && strm->state->status != INIT_STATE))

        return Z_STREAM_ERROR;



    s = strm->state;

    if (s->wrap)

        strm->adler = adler32(strm->adler, dictionary, dictLength);



    if (length < MIN_MATCH) return Z_OK;

    if (length > MAX_DIST(s)) {

        length = MAX_DIST(s);

        dictionary += dictLength - length; /* use the tail of the dictionary */

    }

    zmemcpy(s->window, dictionary, length);

    s->strstart = length;

    s->block_start = (long)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.

     */

    s->ins_h = s->window[0];

    UPDATE_HASH(s, s->ins_h, s->window[1]);

    for (n = 0; n <= length - MIN_MATCH; n++) {

        INSERT_STRING(s, n, hash_head);

    }

    if (hash_head) hash_head = 0;  /* to make compiler happy */

    return Z_OK;

}



/* ========================================================================= */

int ZEXPORT deflateReset (strm)

    z_streamp strm;

{

    deflate_state *s;



//    if (strm == Z_NULL || strm->state == Z_NULL /* ||

//        strm->zalloc == (alloc_func)0 || strm->zfree == (free_func)0 */ ) {

//        return Z_STREAM_ERROR;

//    }



    strm->total_in = strm->total_out = 0;

    strm->msg = Z_NULL; /* use zfree if we ever allocate msg dynamically */

    strm->data_type = Z_UNKNOWN;



    s = (deflate_state *)strm->state;

    s->pending = 0;

    s->pending_out = s->pending_buf;



    if (s->wrap < 0) {

        s->wrap = -s->wrap; /* was made negative by deflate(..., Z_FINISH); */

    }

    s->status = s->wrap ? INIT_STATE : BUSY_STATE;

    strm->adler =

#ifdef GZIP

        s->wrap == 2 ? crc32(0L, Z_NULL, 0) :

#endif

        adler32(0L, Z_NULL, 0);

    s->last_flush = Z_NO_FLUSH;



    _tr_init(s);

    lm_init(s);



    return Z_OK;

}



/* ========================================================================= */

int ZEXPORT deflateSetHeader (strm, head)

    z_streamp strm;

    gz_headerp head;

{

    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;

    if (strm->state->wrap != 2) return Z_STREAM_ERROR;

    strm->state->gzhead = head;

    return Z_OK;

}



/* ========================================================================= */

int ZEXPORT deflatePrime (strm, bits, value)

    z_streamp strm;

    int bits;

    int value;

{

    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;

    strm->state->bi_valid = bits;

    strm->state->bi_buf = (ush)(value & ((1 << bits) - 1));

    return Z_OK;

}



/* ========================================================================= */

int ZEXPORT deflateParams(strm, level, strategy)

    z_streamp strm;

    int level;

    int strategy;

{

    deflate_state *s;

    EdgeZlibDeflateFuncChoice funcChoice;

    int err = Z_OK;



    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;

    s = strm->state;



#ifdef FASTEST

    if (level != 0) level = 1;

#else

    if (level == Z_DEFAULT_COMPRESSION) level = 6;

#endif

    if (level < 0 || level > 9 || strategy < 0 || strategy > Z_FIXED) {

        return Z_STREAM_ERROR;

    }

    funcChoice = configuration_table[s->level].funcChoice;



    if (funcChoice != configuration_table[level].funcChoice && strm->total_in != 0) {

        /* Flush the last buffer: */

        err = deflate(strm, Z_PARTIAL_FLUSH);

    }

    if (s->level != level) {

        s->level = level;

        s->max_lazy_match   = configuration_table[level].max_lazy;

        s->good_match       = configuration_table[level].good_length;

        s->nice_match       = configuration_table[level].nice_length;

        s->max_chain_length = configuration_table[level].max_chain;

    }

    s->strategy = strategy;

    return err;

}



/* ========================================================================= */

int ZEXPORT deflateTune(strm, good_length, max_lazy, nice_length, max_chain)

    z_streamp strm;

    int good_length;

    int max_lazy;

    int nice_length;

    int max_chain;

{

    deflate_state *s;



    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;

    s = strm->state;

    s->good_match = good_length;

    s->max_lazy_match = max_lazy;

    s->nice_match = nice_length;

    s->max_chain_length = max_chain;

    return Z_OK;

}



/* =========================================================================

 * For the default windowBits of 15 and memLevel of 8, this function returns

 * a close to exact, as well as small, upper bound on the compressed size.

 * They are coded as constants here for a reason--if the #define's are

 * changed, then this function needs to be changed as well.  The return

 * value for 15 and 8 only works for those exact settings.

 *

 * For any setting other than those defaults for windowBits and memLevel,

 * the value returned is a conservative worst case for the maximum expansion

 * resulting from using fixed blocks instead of stored blocks, which deflate

 * can emit on compressed data for some combinations of the parameters.

 *

 * This function could be more sophisticated to provide closer upper bounds

 * for every combination of windowBits and memLevel, as well as wrap.

 * But even the conservative upper bound of about 14% expansion does not

 * seem onerous for output buffer allocation.

 */

#if 0

uLong ZEXPORT deflateBound(strm, sourceLen)

    z_streamp strm;

    uLong sourceLen;

{

    deflate_state *s;

    uLong destLen;



    /* conservative upper bound */

    destLen = sourceLen +

              ((sourceLen + 7) >> 3) + ((sourceLen + 63) >> 6) + 11;



    /* if can't get parameters, return conservative bound */

    if (strm == Z_NULL || strm->state == Z_NULL)

        return destLen;



    /* if not default parameters, return conservative bound */

    s = strm->state;

    if (s->w_bits != 15 || s->hash_bits != 8 + 7)

        return destLen;



    /* default settings: return tight bound for that case */

    return compressBound(sourceLen);

}

#endif



/* =========================================================================

 * Put a short in the pending buffer. The 16-bit value is put in MSB order.

 * IN assertion: the stream state is correct and there is enough room in

 * pending_buf.

 */

local void putShortMSB (s, b)

    deflate_state *s;

    uInt b;

{

    put_byte(s, (Byte)(b >> 8));

    put_byte(s, (Byte)(b & 0xff));

}



/* =========================================================================

 * Flush as much pending output as possible. All deflate() output goes

 * through this function so some applications may wish to modify it

 * to avoid allocating a large strm->next_out buffer and copying into it.

 * (See also read_buf()).

 */

local void flush_pending(strm)

    z_streamp strm;

{

    unsigned len = strm->state->pending;



    if (len > strm->avail_out) len = strm->avail_out;

    if (len == 0) return;



    zmemcpy(strm->next_out, strm->state->pending_out, len);

    strm->next_out  += len;

    strm->state->pending_out  += len;

    strm->total_out += len;

    strm->avail_out  -= len;

    strm->state->pending -= len;

    if (strm->state->pending == 0) {

        strm->state->pending_out = strm->state->pending_buf;

    }

}



/* ========================================================================= */

int ZEXPORT deflate (strm, flush)

    z_streamp strm;

    int flush;

{

    int old_flush; /* value of flush param for previous deflate call */

    deflate_state *s;



    if (strm == Z_NULL || strm->state == Z_NULL ||

        flush > Z_FINISH || flush < 0) {

        return Z_STREAM_ERROR;

    }

    s = strm->state;



    if (strm->next_out == Z_NULL ||

        (strm->next_in == Z_NULL && strm->avail_in != 0) ||

        (s->status == FINISH_STATE && flush != Z_FINISH)) {

        ERR_RETURN(strm, Z_STREAM_ERROR);

    }

    if (strm->avail_out == 0) ERR_RETURN(strm, Z_BUF_ERROR);



    s->strm = strm; /* just in case */

    old_flush = s->last_flush;

    s->last_flush = flush;



    /* Write the header */

    if (s->status == INIT_STATE) {

#ifdef GZIP

        if (s->wrap == 2) {

            strm->adler = crc32(0L, Z_NULL, 0);

            put_byte(s, 31);

            put_byte(s, 139);

            put_byte(s, 8);

            if (s->gzhead == NULL) {

                put_byte(s, 0);

                put_byte(s, 0);

                put_byte(s, 0);

                put_byte(s, 0);

                put_byte(s, 0);

                put_byte(s, s->level == 9 ? 2 :

                            (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?

                             4 : 0));

                put_byte(s, OS_CODE);

                s->status = BUSY_STATE;

            }

            else {

                put_byte(s, (s->gzhead->text ? 1 : 0) +

                            (s->gzhead->hcrc ? 2 : 0) +

                            (s->gzhead->extra == Z_NULL ? 0 : 4) +

                            (s->gzhead->name == Z_NULL ? 0 : 8) +

                            (s->gzhead->comment == Z_NULL ? 0 : 16)

                        );

                put_byte(s, (Byte)(s->gzhead->time & 0xff));

                put_byte(s, (Byte)((s->gzhead->time >> 8) & 0xff));

                put_byte(s, (Byte)((s->gzhead->time >> 16) & 0xff));

                put_byte(s, (Byte)((s->gzhead->time >> 24) & 0xff));

                put_byte(s, s->level == 9 ? 2 :

                            (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2 ?

                             4 : 0));

                put_byte(s, s->gzhead->os & 0xff);

                if (s->gzhead->extra != NULL) {

                    put_byte(s, s->gzhead->extra_len & 0xff);

                    put_byte(s, (s->gzhead->extra_len >> 8) & 0xff);

                }

                if (s->gzhead->hcrc)

                    strm->adler = crc32(strm->adler, s->pending_buf,

                                        s->pending);

                s->gzindex = 0;

                s->status = EXTRA_STATE;

            }

        }

        else

#endif

        {

            uInt header = (Z_DEFLATED + ((s->w_bits-8)<<4)) << 8;

            uInt level_flags;



            if (s->strategy >= Z_HUFFMAN_ONLY || s->level < 2)

                level_flags = 0;

            else if (s->level < 6)

                level_flags = 1;

            else if (s->level == 6)

                level_flags = 2;

            else

                level_flags = 3;

            header |= (level_flags << 6);

            if (s->strstart != 0) header |= PRESET_DICT;

            header += 31 - (header % 31);



            s->status = BUSY_STATE;

            putShortMSB(s, header);



            /* Save the adler32 of the preset dictionary: */

            if (s->strstart != 0) {

                putShortMSB(s, (uInt)(strm->adler >> 16));

                putShortMSB(s, (uInt)(strm->adler & 0xffff));

            }

            strm->adler = adler32(0L, Z_NULL, 0);

        }

    }

#ifdef GZIP

    if (s->status == EXTRA_STATE) {

        if (s->gzhead->extra != NULL) {

            uInt beg = s->pending;  /* start of bytes to update crc */



            while (s->gzindex < (s->gzhead->extra_len & 0xffff)) {

                if (s->pending == s->pending_buf_size) {

                    if (s->gzhead->hcrc && s->pending > beg)

                        strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                            s->pending - beg);

                    flush_pending(strm);

                    beg = s->pending;

                    if (s->pending == s->pending_buf_size)

                        break;

                }

                put_byte(s, s->gzhead->extra[s->gzindex]);

                s->gzindex++;

            }

            if (s->gzhead->hcrc && s->pending > beg)

                strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                    s->pending - beg);

            if (s->gzindex == s->gzhead->extra_len) {

                s->gzindex = 0;

                s->status = NAME_STATE;

            }

        }

        else

            s->status = NAME_STATE;

    }

    if (s->status == NAME_STATE) {

        if (s->gzhead->name != NULL) {

            uInt beg = s->pending;  /* start of bytes to update crc */

            int val;



            do {

                if (s->pending == s->pending_buf_size) {

                    if (s->gzhead->hcrc && s->pending > beg)

                        strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                            s->pending - beg);

                    flush_pending(strm);

                    beg = s->pending;

                    if (s->pending == s->pending_buf_size) {

                        val = 1;

                        break;

                    }

                }

                val = s->gzhead->name[s->gzindex++];

                put_byte(s, val);

            } while (val != 0);

            if (s->gzhead->hcrc && s->pending > beg)

                strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                    s->pending - beg);

            if (val == 0) {

                s->gzindex = 0;

                s->status = COMMENT_STATE;

            }

        }

        else

            s->status = COMMENT_STATE;

    }

    if (s->status == COMMENT_STATE) {

        if (s->gzhead->comment != NULL) {

            uInt beg = s->pending;  /* start of bytes to update crc */

            int val;



            do {

                if (s->pending == s->pending_buf_size) {

                    if (s->gzhead->hcrc && s->pending > beg)

                        strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                            s->pending - beg);

                    flush_pending(strm);

                    beg = s->pending;

                    if (s->pending == s->pending_buf_size) {

                        val = 1;

                        break;

                    }

                }

                val = s->gzhead->comment[s->gzindex++];

                put_byte(s, val);

            } while (val != 0);

            if (s->gzhead->hcrc && s->pending > beg)

                strm->adler = crc32(strm->adler, s->pending_buf + beg,

                                    s->pending - beg);

            if (val == 0)

                s->status = HCRC_STATE;

        }

        else

            s->status = HCRC_STATE;

    }

    if (s->status == HCRC_STATE) {

        if (s->gzhead->hcrc) {

            if (s->pending + 2 > s->pending_buf_size)

                flush_pending(strm);

            if (s->pending + 2 <= s->pending_buf_size) {

                put_byte(s, (Byte)(strm->adler & 0xff));

                put_byte(s, (Byte)((strm->adler >> 8) & 0xff));

                strm->adler = crc32(0L, Z_NULL, 0);

                s->status = BUSY_STATE;

            }

        }

        else

            s->status = BUSY_STATE;

    }

#endif



    /* Flush as much pending output as possible */

    if (s->pending != 0) {

        flush_pending(strm);

        if (strm->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:

             */

            s->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_BUF_ERROR.

     */

    } else if (strm->avail_in == 0 && flush <= old_flush &&

               flush != Z_FINISH) {

        ERR_RETURN(strm, Z_BUF_ERROR);

    }



    /* User must not provide more input after the first FINISH: */

    if (s->status == FINISH_STATE && strm->avail_in != 0) {

        ERR_RETURN(strm, Z_BUF_ERROR);

    }



    /* Start a new block or continue the current one.

     */

    if (strm->avail_in != 0 || s->lookahead != 0 ||

        (flush != Z_NO_FLUSH && s->status != FINISH_STATE)) {

        block_state bstate;



		switch ( configuration_table[s->level].funcChoice )

		{

		case kFuncChoiceDeflateStored:

			bstate = deflate_stored(s, flush);

			break;

		case kFuncChoiceDeflateFast:

			bstate = deflate_fast(s, flush);

			break;

		default:

		case kFuncChoiceDeflateSlow:

			bstate = deflate_slow(s, flush);

			break;

		}



        if (bstate == finish_started || bstate == finish_done) {

            s->status = FINISH_STATE;

        }

        if (bstate == need_more || bstate == finish_started) {

            if (strm->avail_out == 0) {

                s->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 == block_done) {

            if (flush == Z_PARTIAL_FLUSH) {

                _tr_align(s);

            } else { /* FULL_FLUSH or SYNC_FLUSH */

                _tr_stored_block(s, (char*)0, 0L, 0);

                /* For a full flush, this empty block will be recognized

                 * as a special marker by inflate_sync().

                 */

                if (flush == Z_FULL_FLUSH) {

                    CLEAR_HASH(s);             /* forget history */

                }

            }

            flush_pending(strm);

            if (strm->avail_out == 0) {

              s->last_flush = -1; /* avoid BUF_ERROR at next call, see above */

              return Z_OK;

            }

        }

    }

    Assert(strm->avail_out > 0, "bug2");



    if (flush != Z_FINISH) return Z_OK;

    if (s->wrap <= 0) return Z_STREAM_END;



    /* Write the trailer */

#ifdef GZIP

    if (s->wrap == 2) {

        put_byte(s, (Byte)(strm->adler & 0xff));

        put_byte(s, (Byte)((strm->adler >> 8) & 0xff));

        put_byte(s, (Byte)((strm->adler >> 16) & 0xff));

        put_byte(s, (Byte)((strm->adler >> 24) & 0xff));

        put_byte(s, (Byte)(strm->total_in & 0xff));

        put_byte(s, (Byte)((strm->total_in >> 8) & 0xff));

        put_byte(s, (Byte)((strm->total_in >> 16) & 0xff));

        put_byte(s, (Byte)((strm->total_in >> 24) & 0xff));

    }

    else

#endif

    {

        putShortMSB(s, (uInt)(strm->adler >> 16));

        putShortMSB(s, (uInt)(strm->adler & 0xffff));

    }

    flush_pending(strm);

    /* If avail_out is zero, the application will call deflate again

     * to flush the rest.

     */

    if (s->wrap > 0) s->wrap = -s->wrap; /* write the trailer only once! */

    return s->pending != 0 ? Z_OK : Z_STREAM_END;

}



/* ========================================================================= */

int ZEXPORT deflateEnd (strm)

    z_streamp strm;

{

    int status;



    if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR;



    status = strm->state->status;

    if (status != INIT_STATE &&

        status != EXTRA_STATE &&

        status != NAME_STATE &&

        status != COMMENT_STATE &&

        status != HCRC_STATE &&

        status != BUSY_STATE &&

        status != FINISH_STATE) {

      return Z_STREAM_ERROR;

    }



    /* Deallocate in reverse order of allocations: */

    //NOTE: these 4 have been made static

	//TRY_FREE(strm, strm->state->pending_buf);

    //TRY_FREE(strm, strm->state->head);

    //TRY_FREE(strm, strm->state->prev);

    //TRY_FREE(strm, strm->state->window);



	//Note: this has been made static

    //ZFREE(strm, strm->state);

    strm->state = Z_NULL;



    return status == BUSY_STATE ? Z_DATA_ERROR : Z_OK;

}



/* =========================================================================

 * Copy the source state to the destination state.

 * To simplify the source, this is not supported for 16-bit MSDOS (which

 * doesn't have enough memory anyway to duplicate compression states).

 */

int ZEXPORT deflateCopy (dest, source)

    z_streamp dest;

    z_streamp source;

{

#ifdef MAXSEG_64K

    return Z_STREAM_ERROR;

#else

    deflate_state *ds;

    deflate_state *ss;

    ushf *overlay;





    if (source == Z_NULL || dest == Z_NULL || source->state == Z_NULL) {

        return Z_STREAM_ERROR;

    }



    ss = source->state;



    zmemcpy(dest, source, sizeof(z_stream));



    //ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state));

	static deflate_state s_deflate_state_copy;

	ds = &s_deflate_state_copy;



    if (ds == Z_NULL) return Z_MEM_ERROR;

    dest->state = (struct internal_state FAR *) ds;

    zmemcpy(ds, ss, sizeof(deflate_state));

    ds->strm = dest;



	//ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte));

	//ds->prev   = (Posf *)  ZALLOC(dest, ds->w_size, sizeof(Pos));

	//ds->head   = (Posf *)  ZALLOC(dest, ds->hash_size, sizeof(Pos));

	//overlay = (ushf *) ZALLOC(dest, ds->lit_bufsize, sizeof(ush)+2);

	static Byte	s_window_copy	[ (1 << MAX_WBITS) * 2 ];

	static Pos	s_prev_copy		[ (1 << MAX_WBITS) * sizeof(Pos) / sizeof(Pos) ];

	static Pos	s_head_copy		[ (1 << (MAX_MEM_LEVEL+7)) * sizeof(Pos) / sizeof(Pos) ];

	static ush	s_overlay_copy	[ (1 << (MAX_MEM_LEVEL+6)) * (sizeof(ush)+2) / sizeof(ush) ];

	ds->window		= &s_window_copy[0];

	ds->prev		= &s_prev_copy[0];

	ds->head		= &s_head_copy[0];

	overlay			= &s_overlay_copy[0];



    ds->pending_buf = (uchf *) overlay;



    if (ds->window == Z_NULL || ds->prev == Z_NULL || ds->head == Z_NULL ||

        ds->pending_buf == Z_NULL) {

        deflateEnd (dest);

        return Z_MEM_ERROR;

    }

    /* following zmemcpy do not work for 16-bit MSDOS */

    zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte));

    zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos));

    zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos));

    zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size);



    ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf);

    ds->d_buf = overlay + ds->lit_bufsize/sizeof(ush);

    ds->l_buf = ds->pending_buf + (1+sizeof(ush))*ds->lit_bufsize;



    ds->l_desc.dyn_tree = ds->dyn_ltree;

    ds->d_desc.dyn_tree = ds->dyn_dtree;

    ds->bl_desc.dyn_tree = ds->bl_tree;



    return Z_OK;

#endif /* MAXSEG_64K */

}



/* ===========================================================================

 * Read a new buffer from the current input stream, update the adler32

 * and total number of bytes read.  All deflate() input goes through

 * this function so some applications may wish to modify it to avoid

 * allocating a large strm->next_in buffer and copying from it.

 * (See also flush_pending()).

 */

local int read_buf(strm, buf, size)

    z_streamp strm;

    Bytef *buf;

    unsigned size;

{

    unsigned len = strm->avail_in;



    if (len > size) len = size;

    if (len == 0) return 0;



    strm->avail_in  -= len;



    if (strm->state->wrap == 1) {

        strm->adler = adler32(strm->adler, strm->next_in, len);

    }

#ifdef GZIP

    else if (strm->state->wrap == 2) {

        strm->adler = crc32(strm->adler, strm->next_in, len);

    }

#endif

    zmemcpy(buf, strm->next_in, len);

    strm->next_in  += len;

    strm->total_in += len;



    return (int)len;

}



/* ===========================================================================

 * Initialize the "longest match" routines for a new zlib stream

 */

local void lm_init (s)

    deflate_state *s;

{

    s->window_size = (ulg)2L*s->w_size;



    CLEAR_HASH(s);



    /* Set the default configuration parameters:

     */

    s->max_lazy_match   = configuration_table[s->level].max_lazy;

    s->good_match       = configuration_table[s->level].good_length;

    s->nice_match       = configuration_table[s->level].nice_length;

    s->max_chain_length = configuration_table[s->level].max_chain;



    s->strstart = 0;

    s->block_start = 0L;

    s->lookahead = 0;

    s->match_length = s->prev_length = MIN_MATCH-1;

    s->match_available = 0;

    s->ins_h = 0;

#ifndef FASTEST

#ifdef ASMV

    match_init(); /* initialize the asm code */

#endif

#endif

}



#ifndef FASTEST

/* ===========================================================================

 * Set match_start to the longest match starting at the given string and

 * return its length. Matches shorter or equal to prev_length are discarded,

 * in which case the result is equal to prev_length and match_start is

 * garbage.

 * IN assertions: cur_match is the head of the hash chain for the current

 *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1

 * OUT assertion: the match length is not greater than s->lookahead.

 */

#ifndef ASMV

/* For 80x86 and 680x0, an optimized version will be provided in match.asm or

 * match.S. The code will be functionally equivalent.

 */

#ifdef __SPU__

uInt longest_match_optimized_c( deflate_state* s, IPos cur_match )

{

	const Bytef* window				= s->window;

	uInt strstart					= s->strstart;



	unsigned chain_length			= s->max_chain_length;		/* max hash chain length */

	register const Bytef *scan		= window + strstart;		/* current string */

	register int len;											/* length of current match */

	uInt prev_length				= s->prev_length;

	int best_len					= prev_length;				/* best match length so far */

	int nice_match					= s->nice_match;			/* stop if match long enough */

	IPos max_dist					= (IPos)MAX_DIST(s);

	IPos limit						= strstart > max_dist

											? strstart - max_dist

											: NIL;

	/* Stop when cur_match becomes <= limit. To simplify the code,

	 * we prevent matches with the string of window index 0.

	 */

	const Posf* prev				= s->prev;

	uInt wmask						= s->w_mask;



	register const Bytef *strend	= window + strstart + MAX_MATCH;

	register Byte scan_end1			= scan[best_len-1];

	register Byte scan_end			= scan[best_len];



	uInt match_start				= s->match_start;

	uInt lookahead					= s->lookahead;



	/* 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.

	 */

	Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");



	/* Do not waste too much time if we already have a good match: */

	if ( prev_length >= s->good_match )

	{

		chain_length >>= 2;

	}



	/* Do not look for matches beyond the end of the input. This is necessary

	 * to make deflate deterministic.

	 */

	nice_match = MY_MIN( (uInt)nice_match, lookahead );



	Assert((ulg)strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");



	COUNT_HITS();	//7954



	do

	{

		Assert(cur_match < strstart, "no future");

		register const Bytef* match = window + cur_match;		/* matched string */



		IPos this_cur_match = cur_match;

		//set up cur_match early ready for next iteration

		cur_match = prev[cur_match & wmask];

		--chain_length;



		COUNT_HITS();	//478619



		/* Skip to next match if the match length cannot increase

		 * or if the match length is less than 2.  Note that the checks below

		 * for insufficient lookahead only occur occasionally for performance

		 * reasons.  Therefore uninitialized memory will be accessed, and

		 * conditional jumps will be made that depend on those values.

		 * However the length of the match is limited to the lookahead, so

		 * the output of deflate is not affected by the uninitialized values.

		 */

		if ( PREDICT_UNLIKELY(	match[best_len]   != scan_end  ||

								match[best_len-1] != scan_end1 ||

								match[0]          != scan[0]   ||

								match[1]          != scan[1] ) )

		{

			COUNT_HITS();	//474308, 99% !

			continue;

		}



		COUNT_HITS();	//4311, 1%



		/* 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.

		 */

		Assert(scan[2] == match[2], "match[2]?");



		scan	+= 3;

		match	+= 3;



		/* We check for insufficient lookahead only every 8th comparison;

		 * the 256th check will be made at strstart+258.

		 */



		const vec_uchar16 mask128		= (const vec_uchar16)(vec_uint4){ 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF };

		vec_uchar16 scanPrev			= ((const vec_uchar16*) &scan[0])[0];

		vec_uchar16 matchPrev			= ((const vec_uchar16*) &match[0])[0];



		vec_uchar16 scanNext			= ((const vec_uchar16*) &scan[0])[1];

		vec_uchar16 matchNext			= ((const vec_uchar16*) &match[0])[1];



		unsigned int scanOffset			= ((unsigned int)scan)&0xF;

		unsigned int matchOffset		= ((unsigned int)match)&0xF;



		vec_uchar16 scanMask128			= spu_slqwbyte( mask128, scanOffset );

		vec_uchar16 matchMask128		= spu_slqwbyte( mask128, matchOffset );



		vec_uchar16 scanPrevRotated		= spu_rlqwbyte( scanPrev, scanOffset );

		vec_uchar16 matchPrevRotated	= spu_rlqwbyte( matchPrev, matchOffset );



		unsigned int matchCount;



		while ( 1 )

		{

			COUNT_HITS();	//4417



			vec_uchar16 scanNextRotated		= spu_rlqwbyte( scanNext, scanOffset );

			vec_uchar16 matchNextRotated	= spu_rlqwbyte( matchNext, matchOffset );



			//combine the two qwords to make our 128 bits of data

			vec_uchar16 scan128				= spu_sel( scanNextRotated, scanPrevRotated, scanMask128 );

			vec_uchar16 match128			= spu_sel( matchNextRotated, matchPrevRotated, matchMask128 );



			//compare all bytes and count how many it is before we find the first difference

			vec_uchar16 cmp128				= spu_cmpeq( scan128, match128 );

			vec_uint4 cmp16					= spu_gather( cmp128 );

			vec_uint4 cmp16hi				= spu_slqwbyte(cmp16, 2);

			vec_uint4 cmp16hineg			= ~cmp16hi;

			vec_uint4 lz					= spu_cntlz(cmp16hineg);



			matchCount = spu_extract(lz,0);



			//speculatively preload ready for next iteration

			scanNext						= ((const vec_uchar16*) scan)[2];

			matchNext						= ((const vec_uchar16*) match)[2];



			scanPrevRotated					= scanNextRotated;

			matchPrevRotated				= matchNextRotated;



			//Note: This version currently checks 16 bytes per iteration.

			//Original version checked 8 bytes per iteration.

			//This means that the escape due to "scan>strend" only happens half as often.



			//matchCount is something between 0 and 16



			if ( PREDICT_UNLIKELY( scan > strend ) )

				break;

			COUNT_HITS();	//4417, 100%



			if ( PREDICT_LIKELY( matchCount < 16 ) )

				break;



			COUNT_HITS();	//106, 2%

			//matchCount must have been 16

			//offset for this loop is 16

			scan	+= 16;

			match	+= 16;

		}



		COUNT_HITS();	//4311



		if ( PREDICT_UNLIKELY( scan > strend ) )

		{

			--scan;

		}

		else

		{

			//matchCount was something between 0 and 16

			//offset for the final loop is between 0 and 15

			unsigned int offset = MY_MIN( matchCount, 15 );

			scan	+= offset;

		}



		Assert(scan <= window+(unsigned)(s->window_size-1), "wild scan");



		len		= MAX_MATCH - (int)(strend - scan);

		scan	= strend - MAX_MATCH;



		if ( PREDICT_LIKELY( len > best_len ) )

		{

			COUNT_HITS();	//3527, 82%

			match_start = this_cur_match;

			best_len = len;

			if ( PREDICT_UNLIKELY( len >= nice_match ) )

			{

				break;

			}

			COUNT_HITS();	//3527, 100%

			scan_end1	= scan[len-1];

			scan_end	= scan[len];

		}



		COUNT_HITS();	//4311

	} while ( PREDICT_LIKELY( (cur_match > limit) && (chain_length != 0) ) );



	COUNT_HITS();	//3527

	s->match_start = match_start;



	return MY_MIN( (uInt)best_len, lookahead );

}

#endif /* __SPU__ */



uInt longest_match_original(s, cur_match)

    deflate_state *s;

    IPos cur_match;                             /* current match */

{

    unsigned chain_length = s->max_chain_length;/* max hash chain length */

    register Bytef *scan = s->window + s->strstart; /* current string */

    register Bytef *match;                       /* matched string */

    register int len;                           /* length of current match */

    int best_len = s->prev_length;              /* best match length so far */

    int nice_match = s->nice_match;             /* stop if match long enough */

    IPos limit = s->strstart > (IPos)MAX_DIST(s) ?

        s->strstart - (IPos)MAX_DIST(s) : NIL;

    /* Stop when cur_match becomes <= limit. To simplify the code,

     * we prevent matches with the string of window index 0.

     */

    Posf *prev = s->prev;

    uInt wmask = s->w_mask;



#ifdef UNALIGNED_OK

    /* Compare two bytes at a time. Note: this is not always beneficial.

     * Try with and without -DUNALIGNED_OK to check.

     */

    register Bytef *strend = s->window + s->strstart + MAX_MATCH - 1;

    register ush scan_start = *(ushf*)scan;

    register ush scan_end   = *(ushf*)(scan+best_len-1);

#else

    register Bytef *strend = s->window + s->strstart + MAX_MATCH;

    register Byte scan_end1  = scan[best_len-1];

    register Byte scan_end   = scan[best_len];

#endif



    /* 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.

     */

    Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");



    /* Do not waste too much time if we already have a good match: */

    if (s->prev_length >= s->good_match) {

        chain_length >>= 2;

    }

    /* Do not look for matches beyond the end of the input. This is necessary

     * to make deflate deterministic.

     */

    if ((uInt)nice_match > s->lookahead) nice_match = s->lookahead;



    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");



    do {

        Assert(cur_match < s->strstart, "no future");

        match = s->window + cur_match;



        /* Skip to next match if the match length cannot increase

         * or if the match length is less than 2.  Note that the checks below

         * for insufficient lookahead only occur occasionally for performance

         * reasons.  Therefore uninitialized memory will be accessed, and

         * conditional jumps will be made that depend on those values.

         * However the length of the match is limited to the lookahead, so

         * the output of deflate is not affected by the uninitialized values.

         */

#if (defined(UNALIGNED_OK) && MAX_MATCH == 258)

        /* This code assumes sizeof(unsigned short) == 2. Do not use

         * UNALIGNED_OK if your compiler uses a different size.

         */

        if (*(ushf*)(match+best_len-1) != scan_end ||

            *(ushf*)match != scan_start) continue;



        /* 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. Compare 2 bytes at a time at

         * strstart+3, +5, ... up to strstart+257. We check for insufficient

         * lookahead only every 4th comparison; the 128th check will be made

         * at strstart+257. If MAX_MATCH-2 is not a multiple of 8, it is

         * necessary to put more guard bytes at the end of the window, or

         * to check more often for insufficient lookahead.

         */

        Assert(scan[2] == match[2], "scan[2]?");

        scan++, match++;

        do {

        } while (*(ushf*)(scan+=2) == *(ushf*)(match+=2) &&

                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&

                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&

                 *(ushf*)(scan+=2) == *(ushf*)(match+=2) &&

                 scan < strend);

        /* The funny "do {}" generates better code on most compilers */



        /* Here, scan <= window+strstart+257 */

        Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");

        if (*scan == *match) scan++;



        len = (MAX_MATCH - 1) - (int)(strend-scan);

        scan = strend - (MAX_MATCH-1);



#else /* UNALIGNED_OK */



        if (match[best_len]   != scan_end  ||

            match[best_len-1] != scan_end1 ||

            *match            != *scan     ||

            *++match          != 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++;

        Assert(*scan == *match, "match[2]?");



        /* We check for insufficient lookahead only every 8th comparison;

         * the 256th check will be made at strstart+258.

         */

        do {

        } while (*++scan == *++match && *++scan == *++match &&

                 *++scan == *++match && *++scan == *++match &&

                 *++scan == *++match && *++scan == *++match &&

                 *++scan == *++match && *++scan == *++match &&

                 scan < strend);



        Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");



        len = MAX_MATCH - (int)(strend - scan);

        scan = strend - MAX_MATCH;



#endif /* UNALIGNED_OK */



        if (len > best_len) {

            s->match_start = cur_match;

            best_len = len;

            if (len >= nice_match) break;

#ifdef UNALIGNED_OK

            scan_end = *(ushf*)(scan+best_len-1);

#else

            scan_end1  = scan[best_len-1];

            scan_end   = scan[best_len];

#endif

        }

    } while ((cur_match = prev[cur_match & wmask]) > limit

             && --chain_length != 0);



    if ((uInt)best_len <= s->lookahead) return (uInt)best_len;

    return s->lookahead;

}

#endif /* ASMV */

#endif /* FASTEST */



/* ---------------------------------------------------------------------------

 * Optimized version for level == 1 or strategy == Z_RLE only

 */

local uInt longest_match_fast(s, cur_match)

    deflate_state *s;

    IPos cur_match;                             /* current match */

{

    register Bytef *scan = s->window + s->strstart; /* current string */

    register Bytef *match;                       /* matched string */

    register int len;                           /* length of current match */

    register Bytef *strend = s->window + s->strstart + MAX_MATCH;



    /* 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.

     */

    Assert(s->hash_bits >= 8 && MAX_MATCH == 258, "Code too clever");



    Assert((ulg)s->strstart <= s->window_size-MIN_LOOKAHEAD, "need lookahead");



    Assert(cur_match < s->strstart, "no future");



    match = s->window + cur_match;



    /* Return failure if the match length is less than 2:

     */

    if (match[0] != scan[0] || match[1] != scan[1]) return MIN_MATCH-1;



    /* 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 += 2;

    Assert(*scan == *match, "match[2]?");



    /* We check for insufficient lookahead only every 8th comparison;

     * the 256th check will be made at strstart+258.

     */

    do {

    } while (*++scan == *++match && *++scan == *++match &&

             *++scan == *++match && *++scan == *++match &&

             *++scan == *++match && *++scan == *++match &&

             *++scan == *++match && *++scan == *++match &&

             scan < strend);



    Assert(scan <= s->window+(unsigned)(s->window_size-1), "wild scan");



    len = MAX_MATCH - (int)(strend - scan);



    if (len < MIN_MATCH) return MIN_MATCH - 1;



    s->match_start = cur_match;

    return (uInt)len <= s->lookahead ? (uInt)len : s->lookahead;

}



#ifdef DEBUG

/* ===========================================================================

 * Check that the match at match_start is indeed a match.

 */

local void check_match(s, start, match, length)

    deflate_state *s;

    IPos start, match;

    int length;

{

    /* check that the match is indeed a match */

    if (zmemcmp(s->window + match,

                s->window + start, length) != EQUAL) {

        fprintf(stderr, " start %u, match %u, length %d\n",

                start, match, length);

        do {

            fprintf(stderr, "%c%c", s->window[match++], s->window[start++]);

        } while (--length != 0);

        z_error("invalid match");

    }

    if (z_verbose > 1) {

        fprintf(stderr,"\\[%d,%d]", start-match, length);

        do { putc(s->window[start++], stderr); } while (--length != 0);

    }

}

#else

#  define check_match(s, start, match, length)

#endif /* DEBUG */



/* ===========================================================================

 * 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).

 */

local void fill_window(s)

    deflate_state *s;

{

    register unsigned n, m;

    register Posf *p;

    unsigned more;    /* Amount of free space at the end of the window. */

    uInt wsize = s->w_size;



    do {

        more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart);



        /* Deal with !@#$% 64K limit: */

        if (sizeof(int) <= 2) {

            if (more == 0 && s->strstart == 0 && s->lookahead == 0) {

                more = wsize;



            } else if (more == (unsigned)(-1)) {

                /* Very unlikely, but possible on 16 bit machine if

                 * strstart == 0 && lookahead == 1 (input done a 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.

         */

        if (s->strstart >= wsize+MAX_DIST(s)) {



            zmemcpy(s->window, s->window+wsize, (unsigned)wsize);

            s->match_start -= wsize;

            s->strstart    -= wsize; /* we now have strstart >= MAX_DIST */

            s->block_start -= (long) wsize;



            /* 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.)

             */

            /* %%% avoid this when Z_RLE */

            n = s->hash_size;

            p = &s->head[n];

            do {

                m = *--p;

                *p = (Pos)(m >= wsize ? m-wsize : NIL);

            } while (--n);



            n = wsize;

#ifndef FASTEST

            p = &s->prev[n];

            do {

                m = *--p;

                *p = (Pos)(m >= wsize ? m-wsize : NIL);

                /* If n is not on any hash chain, prev[n] is garbage but

                 * its value will never be used.

                 */

            } while (--n);

#endif

            more += wsize;

        }

        if (s->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.

         */

        Assert(more >= 2, "more < 2");



        n = read_buf(s->strm, s->window + s->strstart + s->lookahead, more);

        s->lookahead += n;



        /* Initialize the hash value now that we have some input: */

        if (s->lookahead >= MIN_MATCH) {

            s->ins_h = s->window[s->strstart];

            UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);

#if MIN_MATCH != 3

            Call UPDATE_HASH() MIN_MATCH-3 more times

#endif

        }

        /* 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 (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0);

}



/* ===========================================================================

 * Flush the current block, with given end-of-file flag.

 * IN assertion: strstart is set to the end of the current match.

 */

#define FLUSH_BLOCK_ONLY(s, eof) { \

   _tr_flush_block(s, (s->block_start >= 0L ? \

                   (charf *)&s->window[(unsigned)s->block_start] : \

                   (charf *)Z_NULL), \

                (ulg)((long)s->strstart - s->block_start), \

                (eof)); \

   s->block_start = s->strstart; \

   flush_pending(s->strm); \

   Tracev((stderr,"[FLUSH]")); \

}



/* Same but force premature exit if necessary. */

#define FLUSH_BLOCK(s, eof) { \

   FLUSH_BLOCK_ONLY(s, eof); \

   if (s->strm->avail_out == 0) return (eof) ? finish_started : need_more; \

}



/* ===========================================================================

 * 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.

 */

local block_state deflate_stored(s, flush)

    deflate_state *s;

    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:

     */

    ulg max_block_size = 0xffff;

    ulg max_start;



    if (max_block_size > s->pending_buf_size - 5) {

        max_block_size = s->pending_buf_size - 5;

    }



    /* Copy as much as possible from input to output: */

    for (;;) {

        /* Fill the window as much as possible: */

        if (s->lookahead <= 1) {



            Assert(s->strstart < s->w_size+MAX_DIST(s) ||

                   s->block_start >= (long)s->w_size, "slide too late");



            fill_window(s);

            if (s->lookahead == 0 && flush == Z_NO_FLUSH) return need_more;



            if (s->lookahead == 0) break; /* flush the current block */

        }

        Assert(s->block_start >= 0L, "block gone");



        s->strstart += s->lookahead;

        s->lookahead = 0;



        /* Emit a stored block if pending_buf will be full: */

        max_start = s->block_start + max_block_size;

        if (s->strstart == 0 || (ulg)s->strstart >= max_start) {

            /* strstart == 0 is possible when wraparound on 16-bit machine */

            s->lookahead = (uInt)(s->strstart - max_start);

            s->strstart = (uInt)max_start;

            FLUSH_BLOCK(s, 0);

        }

        /* Flush if we may have to slide, otherwise block_start may become

         * negative and the data will be gone:

         */

        if (s->strstart - (uInt)s->block_start >= MAX_DIST(s)) {

            FLUSH_BLOCK(s, 0);

        }

    }

    FLUSH_BLOCK(s, flush == Z_FINISH);

    return flush == Z_FINISH ? finish_done : block_done;

}



/* ===========================================================================

 * 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.

 */

local block_state deflate_fast(s, flush)

    deflate_state *s;

    int flush;

{

    IPos hash_head = NIL; /* head of the hash chain */

    int bflush;           /* set if current block must be flushed */



    for (;;) {

        /* 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 (s->lookahead < MIN_LOOKAHEAD) {

            fill_window(s);

            if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {

                return need_more;

            }

            if (s->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 (s->lookahead >= MIN_MATCH) {

            INSERT_STRING(s, s->strstart, hash_head);

        }



        /* Find the longest match, discarding those <= prev_length.

         * At this point we have always match_length < MIN_MATCH

         */

        if (hash_head != NIL && s->strstart - hash_head <= MAX_DIST(s)) {

            /* 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).

             */

#ifdef FASTEST

            if ((s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) ||

                (s->strategy == Z_RLE && s->strstart - hash_head == 1)) {

                s->match_length = longest_match_fast (s, hash_head);

            }

#else

            if (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {

                s->match_length = longest_match (s, hash_head);

            } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {

                s->match_length = longest_match_fast (s, hash_head);

            }

#endif

            /* longest_match() or longest_match_fast() sets match_start */

        }

        if (s->match_length >= MIN_MATCH) {

            check_match(s, s->strstart, s->match_start, s->match_length);



            _tr_tally_dist(s, s->strstart - s->match_start,

                           s->match_length - MIN_MATCH, bflush);



            s->lookahead -= s->match_length;



            /* Insert new strings in the hash table only if the match length

             * is not too large. This saves time but degrades compression.

             */

#ifndef FASTEST

            if (s->match_length <= s->max_insert_length &&

                s->lookahead >= MIN_MATCH) {

                s->match_length--; /* string at strstart already in table */

                do {

                    s->strstart++;

                    INSERT_STRING(s, s->strstart, hash_head);

                    /* strstart never exceeds WSIZE-MAX_MATCH, so there are

                     * always MIN_MATCH bytes ahead.

                     */

                } while (--s->match_length != 0);

                s->strstart++;

            } else

#endif

            {

                s->strstart += s->match_length;

                s->match_length = 0;

                s->ins_h = s->window[s->strstart];

                UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]);

#if MIN_MATCH != 3

                Call UPDATE_HASH() MIN_MATCH-3 more times

#endif

                /* 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 */

            Tracevv((stderr,"%c", s->window[s->strstart]));

            _tr_tally_lit (s, s->window[s->strstart], bflush);

            s->lookahead--;

            s->strstart++;

        }

        if (bflush) FLUSH_BLOCK(s, 0);

    }

    FLUSH_BLOCK(s, flush == Z_FINISH);

    return flush == Z_FINISH ? finish_done : block_done;

}



#ifndef FASTEST

/* ===========================================================================

 * 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.

 */

local block_state deflate_slow(s, flush)

    deflate_state *s;

    int flush;

{

    IPos hash_head = NIL;    /* head of hash chain */

    int bflush;              /* set if current block must be flushed */



    /* Process the input block. */

    for (;;) {

        /* 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 (s->lookahead < MIN_LOOKAHEAD) {

            fill_window(s);

            if (s->lookahead < MIN_LOOKAHEAD && flush == Z_NO_FLUSH) {

                return need_more;

            }

            if (s->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 (s->lookahead >= MIN_MATCH) {

            INSERT_STRING(s, s->strstart, hash_head);

        }



        /* Find the longest match, discarding those <= prev_length.

         */

        s->prev_length = s->match_length, s->prev_match = s->match_start;

        s->match_length = MIN_MATCH-1;



        if (hash_head != NIL && s->prev_length < s->max_lazy_match &&

            s->strstart - hash_head <= MAX_DIST(s)) {

            /* 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 (s->strategy != Z_HUFFMAN_ONLY && s->strategy != Z_RLE) {

                s->match_length = longest_match (s, hash_head);

            } else if (s->strategy == Z_RLE && s->strstart - hash_head == 1) {

                s->match_length = longest_match_fast (s, hash_head);

            }

            /* longest_match() or longest_match_fast() sets match_start */



            if (s->match_length <= 5 && (s->strategy == Z_FILTERED

#if TOO_FAR <= 32767

                || (s->match_length == MIN_MATCH &&

                    s->strstart - s->match_start > TOO_FAR)

#endif

                )) {



                /* If prev_match is also MIN_MATCH, match_start is garbage

                 * but we will ignore the current match anyway.

                 */

                s->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 (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {

            uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;

            /* Do not insert strings in hash table beyond this. */



            check_match(s, s->strstart-1, s->prev_match, s->prev_length);



            _tr_tally_dist(s, s->strstart -1 - s->prev_match,

                           s->prev_length - MIN_MATCH, bflush);



            /* 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.

             */

            s->lookahead -= s->prev_length-1;

            s->prev_length -= 2;

            do {

                if (++s->strstart <= max_insert) {

                    INSERT_STRING(s, s->strstart, hash_head);

                }

            } while (--s->prev_length != 0);

            s->match_available = 0;

            s->match_length = MIN_MATCH-1;

            s->strstart++;



            if (bflush) FLUSH_BLOCK(s, 0);



        } else if (s->match_available) {

            /* 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.

             */

            Tracevv((stderr,"%c", s->window[s->strstart-1]));

            _tr_tally_lit(s, s->window[s->strstart-1], bflush);

            if (bflush) {

                FLUSH_BLOCK_ONLY(s, 0);

            }

            s->strstart++;

            s->lookahead--;

            if (s->strm->avail_out == 0) return need_more;

        } else {

            /* There is no previous match to compare with, wait for

             * the next step to decide.

             */

            s->match_available = 1;

            s->strstart++;

            s->lookahead--;

        }

    }

    Assert (flush != Z_NO_FLUSH, "no flush?");

    if (s->match_available) {

        Tracevv((stderr,"%c", s->window[s->strstart-1]));

        _tr_tally_lit(s, s->window[s->strstart-1], bflush);

        s->match_available = 0;

    }

    FLUSH_BLOCK(s, flush == Z_FINISH);

    return flush == Z_FINISH ? finish_done : block_done;

}

#endif /* FASTEST */



#if 0

/* ===========================================================================

 * For Z_RLE, simply look for runs of bytes, generate matches only of distance

 * one.  Do not maintain a hash table.  (It will be regenerated if this run of

 * deflate switches away from Z_RLE.)

 */

local block_state deflate_rle(s, flush)

    deflate_state *s;

    int flush;

{

    int bflush;         /* set if current block must be flushed */

    uInt run;           /* length of run */

    uInt max;           /* maximum length of run */

    uInt prev;          /* byte at distance one to match */

    Bytef *scan;        /* scan for end of run */



    for (;;) {

        /* Make sure that we always have enough lookahead, except

         * at the end of the input file. We need MAX_MATCH bytes

         * for the longest encodable run.

         */

        if (s->lookahead < MAX_MATCH) {

            fill_window(s);

            if (s->lookahead < MAX_MATCH && flush == Z_NO_FLUSH) {

                return need_more;

            }

            if (s->lookahead == 0) break; /* flush the current block */

        }



        /* See how many times the previous byte repeats */

        run = 0;

        if (s->strstart > 0) {      /* if there is a previous byte, that is */

            max = s->lookahead < MAX_MATCH ? s->lookahead : MAX_MATCH;

            scan = s->window + s->strstart - 1;

            prev = *scan++;

            do {

                if (*scan++ != prev)

                    break;

            } while (++run < max);

        }



        /* Emit match if have run of MIN_MATCH or longer, else emit literal */

        if (run >= MIN_MATCH) {

            check_match(s, s->strstart, s->strstart - 1, run);

            _tr_tally_dist(s, 1, run - MIN_MATCH, bflush);

            s->lookahead -= run;

            s->strstart += run;

        } else {

            /* No match, output a literal byte */

            Tracevv((stderr,"%c", s->window[s->strstart]));

            _tr_tally_lit (s, s->window[s->strstart], bflush);

            s->lookahead--;

            s->strstart++;

        }

        if (bflush) FLUSH_BLOCK(s, 0);

    }

    FLUSH_BLOCK(s, flush == Z_FINISH);

    return flush == Z_FINISH ? finish_done : block_done;

}

#endif

