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#include <windows.h>

#include <stdio.h>

#include <tchar.h>

#include "zip.h"

// THIS FILE is almost entirely based upon code by info-zip.

// It has been modified by Lucian Wischik. The modifications

// were a complete rewrite of the bit of code that generates the

// layout of the zipfile, and support for zipping to/from memory

// or handles or pipes or pagefile or diskfiles, encryption, unicode.

// The original code may be found at http://www.info-zip.org

// The original copyright text follows.

//

//

//

// This is version 1999-Oct-05 of the Info-ZIP copyright and license.

// The definitive version of this document should be available at

// ftp://ftp.cdrom.com/pub/infozip/license.html indefinitely.

//

// Copyright (c) 1990-1999 Info-ZIP.  All rights reserved.

//

// For the purposes of this copyright and license, "Info-ZIP" is defined as

// the following set of individuals:

//

//   Mark Adler, John Bush, Karl Davis, Harald Denker, Jean-Michel Dubois,

//   Jean-loup Gailly, Hunter Goatley, Ian Gorman, Chris Herborth, Dirk Haase,

//   Greg Hartwig, Robert Heath, Jonathan Hudson, Paul Kienitz, David Kirschbaum,

//   Johnny Lee, Onno van der Linden, Igor Mandrichenko, Steve P. Miller,

//   Sergio Monesi, Keith Owens, George Petrov, Greg Roelofs, Kai Uwe Rommel,

//   Steve Salisbury, Dave Smith, Christian Spieler, Antoine Verheijen,

//   Paul von Behren, Rich Wales, Mike White

//

// This software is provided "as is," without warranty of any kind, express

// or implied.  In no event shall Info-ZIP or its contributors be held liable

// for any direct, indirect, incidental, special or consequential damages

// arising out of the use of or inability to use this software.

//

// Permission is granted to anyone to use this software for any purpose,

// including commercial applications, and to alter it and redistribute it

// freely, subject to the following restrictions:

//

//    1. Redistributions of source code must retain the above copyright notice,

//       definition, disclaimer, and this list of conditions.

//

//    2. Redistributions in binary form must reproduce the above copyright

//       notice, definition, disclaimer, and this list of conditions in

//       documentation and/or other materials provided with the distribution.

//

//    3. Altered versions--including, but not limited to, ports to new operating

//       systems, existing ports with new graphical interfaces, and dynamic,

//       shared, or static library versions--must be plainly marked as such

//       and must not be misrepresented as being the original source.  Such

//       altered versions also must not be misrepresented as being Info-ZIP

//       releases--including, but not limited to, labeling of the altered

//       versions with the names "Info-ZIP" (or any variation thereof, including,

//       but not limited to, different capitalizations), "Pocket UnZip," "WiZ"

//       or "MacZip" without the explicit permission of Info-ZIP.  Such altered

//       versions are further prohibited from misrepresentative use of the

//       Zip-Bugs or Info-ZIP e-mail addresses or of the Info-ZIP URL(s).

//

//    4. Info-ZIP retains the right to use the names "Info-ZIP," "Zip," "UnZip,"

//       "WiZ," "Pocket UnZip," "Pocket Zip," and "MacZip" for its own source and

//       binary releases.

//

typedef unsigned char uch;      // unsigned 8-bit value

typedef unsigned short ush;     // unsigned 16-bit value

typedef unsigned long ulg;      // unsigned 32-bit value

typedef size_t extent;          // file size

typedef unsigned Pos;   // must be at least 32 bits

typedef unsigned IPos; // A Pos is an index in the character window. Pos is used only for parameter passing

#ifndef EOF

#define EOF (-1)

#endif

// Error return values.  The values 0..4 and 12..18 follow the conventions

// of PKZIP.   The values 4..10 are all assigned to "insufficient memory"

// by PKZIP, so the codes 5..10 are used here for other purposes.

#define ZE_MISS         -1      // used by procname(), zipbare()

#define ZE_OK           0       // success

#define ZE_EOF          2       // unexpected end of zip file

#define ZE_FORM         3       // zip file structure error

#define ZE_MEM          4       // out of memory

#define ZE_LOGIC        5       // internal logic error

#define ZE_BIG          6       // entry too large to split

#define ZE_NOTE         7       // invalid comment format

#define ZE_TEST         8       // zip test (-T) failed or out of memory

#define ZE_ABORT        9       // user interrupt or termination

#define ZE_TEMP         10      // error using a temp file

#define ZE_READ         11      // read or seek error

#define ZE_NONE         12      // nothing to do

#define ZE_NAME         13      // missing or empty zip file

#define ZE_WRITE        14      // error writing to a file

#define ZE_CREAT        15      // couldn't open to write

#define ZE_PARMS        16      // bad command line

#define ZE_OPEN         18      // could not open a specified file to read

#define ZE_MAXERR       18      // the highest error number

// internal file attribute

#define UNKNOWN (-1)

#define BINARY  0

#define ASCII   1

#define BEST -1                 // Use best method (deflation or store)

#define STORE 0                 // Store method

#define DEFLATE 8               // Deflation method

#define CRCVAL_INITIAL  0L

// MSDOS file or directory attributes

#define MSDOS_HIDDEN_ATTR 0x02

#define MSDOS_DIR_ATTR 0x10

// Lengths of headers after signatures in bytes

#define LOCHEAD 26

#define CENHEAD 42

#define ENDHEAD 18

// Definitions for extra field handling:

#define EB_HEADSIZE       4     /* length of a extra field block header */

#define EB_LEN            2     /* offset of data length field in header */

#define EB_UT_MINLEN      1     /* minimal UT field contains Flags byte */

#define EB_UT_FLAGS       0     /* byte offset of Flags field */

#define EB_UT_TIME1       1     /* byte offset of 1st time value */

#define EB_UT_FL_MTIME    (1 << 0)      /* mtime present */

#define EB_UT_FL_ATIME    (1 << 1)      /* atime present */

#define EB_UT_FL_CTIME    (1 << 2)      /* ctime present */

#define EB_UT_LEN(n)      (EB_UT_MINLEN + 4 * (n))

#define EB_L_UT_SIZE    (EB_HEADSIZE + EB_UT_LEN(3))

#define EB_C_UT_SIZE    (EB_HEADSIZE + EB_UT_LEN(1))

// Macros for writing machine integers to little-endian format

#define PUTSH(a,f) {char _putsh_c=(char)((a)&0xff); wfunc(param,&_putsh_c,1); _putsh_c=(char)((a)>>8); wfunc(param,&_putsh_c,1);}

#define PUTLG(a,f) {PUTSH((a) & 0xffff,(f)) PUTSH((a) >> 16,(f))}

// -- Structure of a ZIP file --

// Signatures for zip file information headers

#define LOCSIG     0x04034b50L

#define CENSIG     0x02014b50L

#define ENDSIG     0x06054b50L

#define EXTLOCSIG  0x08074b50L

#define MIN_MATCH  3

#define MAX_MATCH  258

// The minimum and maximum match lengths

#define WSIZE  (0x8000)

// Maximum window size = 32K. If you are really short of memory, compile

// with a smaller WSIZE but this reduces the compression ratio for files

// of size > WSIZE. WSIZE must be a power of two in the current implementation.

//

#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.

//

#define MAX_DIST  (WSIZE-MIN_LOOKAHEAD)

// In order to simplify the code, particularly on 16 bit machines, match

// distances are limited to MAX_DIST instead of WSIZE.

//

#define ZIP_HANDLE   1

#define ZIP_FILENAME 2

#define ZIP_MEMORY   3

#define ZIP_FOLDER   4

// ===========================================================================

// Constants

//

#define MAX_BITS 15

// All codes must not exceed MAX_BITS bits

#define MAX_BL_BITS 7

// Bit length codes must not exceed MAX_BL_BITS bits

#define LENGTH_CODES 29

// number of length codes, not counting the special END_BLOCK code

#define LITERALS  256

// number of literal bytes 0..255

#define END_BLOCK 256

// end of block literal code

#define L_CODES (LITERALS+1+LENGTH_CODES)

// number of Literal or Length codes, including the END_BLOCK code

#define D_CODES   30

// number of distance codes

#define BL_CODES  19

// number of codes used to transfer the bit lengths

#define STORED_BLOCK 0

#define STATIC_TREES 1

#define DYN_TREES    2

// The three kinds of block type

#define LIT_BUFSIZE  0x8000

#define DIST_BUFSIZE  LIT_BUFSIZE

// Sizes of match buffers for literals/lengths and distances.  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).

//   - 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

// The current code is general and allows DIST_BUFSIZE < LIT_BUFSIZE (to save

// memory at the expense of compression). Some optimizations would be possible

// if we rely on DIST_BUFSIZE == LIT_BUFSIZE.

//

#define REP_3_6      16

// repeat previous bit length 3-6 times (2 bits of repeat count)

#define REPZ_3_10    17

// repeat a zero length 3-10 times  (3 bits of repeat count)

#define REPZ_11_138  18

// repeat a zero length 11-138 times  (7 bits of repeat count)

#define HEAP_SIZE (2*L_CODES+1)

// maximum heap size

// ===========================================================================

// Local data used by the "bit string" routines.

//

#define Buf_size (8 * 2*sizeof(char))

// Number of bits used within bi_buf. (bi_buf may be implemented on

// more than 16 bits on some systems.)

// Output a 16 bit value to the bit stream, lower (oldest) byte first

#define PUTSHORT(state,w) \

{ if (state.bs.out_offset >= state.bs.out_size-1) \

    state.flush_outbuf(state.param,state.bs.out_buf, &state.bs.out_offset); \

  state.bs.out_buf[state.bs.out_offset++] = (char) ((w) & 0xff); \

  state.bs.out_buf[state.bs.out_offset++] = (char) ((ush)(w) >> 8); \

}

#define PUTBYTE(state,b) \

{ if (state.bs.out_offset >= state.bs.out_size) \

    state.flush_outbuf(state.param,state.bs.out_buf, &state.bs.out_offset); \

  state.bs.out_buf[state.bs.out_offset++] = (char) (b); \

}

// DEFLATE.CPP HEADER

#define HASH_BITS  15

// For portability to 16 bit machines, do not use values above 15.

#define HASH_SIZE (unsigned)(1<<HASH_BITS)

#define HASH_MASK (HASH_SIZE-1)

#define WMASK     (WSIZE-1)

// HASH_SIZE and WSIZE must be powers of two

#define NIL 0

// Tail of hash chains

#define FAST 4

#define SLOW 2

// speed options for the general purpose bit flag

#define TOO_FAR 4096

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

#define EQUAL 0

// result of memcmp for equal strings

// ===========================================================================

// Local data used by the "longest match" routines.

#define H_SHIFT  ((HASH_BITS+MIN_MATCH-1)/MIN_MATCH)

// Number of bits by which ins_h and del_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:

//   H_SHIFT * MIN_MATCH >= HASH_BITS

#define max_insert_length  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.

const int extra_lbits[LENGTH_CODES] // extra bits for each length code

   = {0,0,0,0,0,0,0,0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,0};

const int extra_dbits[D_CODES] // extra bits for each distance code

   = {0,0,0,0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,13,13};

const int extra_blbits[BL_CODES]// extra bits for each bit length code

   = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7};

const uch bl_order[BL_CODES] = {16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15};

// The lengths of the bit length codes are sent in order of decreasing

// probability, to avoid transmitting the lengths for unused bit length codes.

typedef struct config {

   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;

} config;

// Values for max_lazy_match, good_match, nice_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.

//

const config configuration_table[10] = {

//  good lazy nice chain

    {0,    0,  0,    0},  // 0 store only

    {4,    4,  8,    4},  // 1 maximum speed, no lazy matches

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

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

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

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

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

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

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

    {32, 258, 258, 4096}};// 9 maximum compression */

// 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.

// Data structure describing a single value and its code string.

typedef struct ct_data {

    union {

        ush  freq;       // frequency count

        ush  code;       // bit string

    } fc;

    union {

        ush  dad;        // father node in Huffman tree

        ush  len;        // length of bit string

    } dl;

} ct_data;

typedef struct tree_desc {

    ct_data *dyn_tree;      // the dynamic tree

    ct_data *static_tree;   // corresponding static tree or NULL

    const int *extra_bits;  // extra bits for each code or NULL

    int     extra_base;     // base index for extra_bits

    int     elems;          // max number of elements in the tree

    int     max_length;     // max bit length for the codes

    int     max_code;       // largest code with non zero frequency

} tree_desc;

class TTreeState

{ public:

  TTreeState();

  ct_data dyn_ltree[HEAP_SIZE];    // literal and length tree

  ct_data dyn_dtree[2*D_CODES+1];  // distance tree

  ct_data static_ltree[L_CODES+2]; // the static literal tree...

  // ... Since the bit lengths are imposed, there is no need for the L_CODES

  // extra codes used during heap construction. However the codes 286 and 287

  // are needed to build a canonical tree (see ct_init below).

  ct_data static_dtree[D_CODES]; // the static distance tree...

  // ... (Actually a trivial tree since all codes use 5 bits.)

  ct_data bl_tree[2*BL_CODES+1];  // Huffman tree for the bit lengths

  tree_desc l_desc;

  tree_desc d_desc;

  tree_desc bl_desc;

  ush bl_count[MAX_BITS+1];  // number of codes at each bit length for an optimal tree

  int heap[2*L_CODES+1]; // heap used to build the Huffman trees

  int heap_len;               // number of elements in the heap

  int heap_max;               // element of largest frequency

  // The sons of heap[n] are heap[2*n] and heap[2*n+1]. heap[0] is not used.

  // The same heap array is used to build all trees.

  uch depth[2*L_CODES+1];

  // Depth of each subtree used as tie breaker for trees of equal frequency

  uch length_code[MAX_MATCH-MIN_MATCH+1];

  // length code for each normalized match length (0 == MIN_MATCH)

  uch dist_code[512];

  // distance codes. The first 256 values correspond to the distances

  // 3 .. 258, the last 256 values correspond to the top 8 bits of

  // the 15 bit distances.

  int base_length[LENGTH_CODES];

  // First normalized length for each code (0 = MIN_MATCH)

  int base_dist[D_CODES];

  // First normalized distance for each code (0 = distance of 1)

  uch far l_buf[LIT_BUFSIZE];  // buffer for literals/lengths

  ush far d_buf[DIST_BUFSIZE]; // buffer for distances

  uch flag_buf[(LIT_BUFSIZE/8)];

  // flag_buf is a bit array distinguishing literals from lengths in

  // l_buf, and thus indicating the presence or absence of a distance.

  unsigned last_lit;    // running index in l_buf

  unsigned last_dist;   // running index in d_buf

  unsigned last_flags;  // running index in flag_buf

  uch flags;            // current flags not yet saved in flag_buf

  uch flag_bit;         // current bit used in flags

  // bits are filled in flags starting at bit 0 (least significant).

  // Note: these flags are overkill in the current code since we don't

  // take advantage of DIST_BUFSIZE == LIT_BUFSIZE.

  ulg opt_len;          // bit length of current block with optimal trees

  ulg static_len;       // bit length of current block with static trees

  ulg cmpr_bytelen;     // total byte length of compressed file

  ulg cmpr_len_bits;    // number of bits past 'cmpr_bytelen'

  ulg input_len;        // total byte length of input file

  // input_len is for debugging only since we can get it by other means.

  ush *file_type;       // pointer to UNKNOWN, BINARY or ASCII

//  int *file_method;     // pointer to DEFLATE or STORE

};

TTreeState::TTreeState()

{ tree_desc a = {dyn_ltree, static_ltree, extra_lbits, LITERALS+1, L_CODES, MAX_BITS, 0};  l_desc = a;

  tree_desc b = {dyn_dtree, static_dtree, extra_dbits, 0,          D_CODES, MAX_BITS, 0};  d_desc = b;

  tree_desc c = {bl_tree, NULL,       extra_blbits, 0,         BL_CODES, MAX_BL_BITS, 0};  bl_desc = c;

  last_lit=0;

  last_dist=0;

  last_flags=0;

}

class TBitState

{ public:

  int flush_flg;

  //

  unsigned bi_buf;

  // Output buffer. bits are inserted starting at the bottom (least significant

  // bits). The width of bi_buf must be at least 16 bits.

  int bi_valid;

  // Number of valid bits in bi_buf.  All bits above the last valid bit

  // are always zero.

  char *out_buf;

  // Current output buffer.

  unsigned out_offset;

  // Current offset in output buffer.

  // On 16 bit machines, the buffer is limited to 64K.

  unsigned out_size;

  // Size of current output buffer

  ulg bits_sent;   // bit length of the compressed data  only needed for debugging???

};

class TDeflateState

{ public:

  TDeflateState() {window_size=0;}

  uch    window[2L*WSIZE];

  // 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: limit the window size to WSIZE+CBSZ if SMALL_MEM (the code would

  // be less efficient since the data would have to be copied WSIZE/CBSZ times)

  Pos    prev[WSIZE];

  // 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.

  Pos    head[HASH_SIZE];

  // Heads of the hash chains or NIL. If your compiler thinks that

  // HASH_SIZE is a dynamic value, recompile with -DDYN_ALLOC.

  ulg window_size;

  // window size, 2*WSIZE except for MMAP or BIG_MEM, where it is the

  // input file length plus MIN_LOOKAHEAD.

  long block_start;

  // window position at the beginning of the current output block. Gets

  // negative when the window is moved backwards.

  int sliding;

  // Set to false when the input file is already in memory

  unsigned ins_h;  // hash index of string to be inserted

  unsigned int prev_length;

  // Length of the best match at previous step. Matches not greater than this

  // are discarded. This is used in the lazy match evaluation.

  unsigned strstart;         // start of string to insert

  unsigned match_start; // start of matching string

  int      eofile;           // flag set at end of input file

  unsigned lookahead;        // number of valid bytes ahead in window

  unsigned max_chain_length;

  // To speed up deflation, hash chains are never searched beyond this length.

  // A higher limit improves compression ratio but degrades the speed.

  unsigned int max_lazy_match;

  // 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.

  unsigned good_match;

  // Use a faster search when the previous match is longer than this

  int nice_match; // Stop searching when current match exceeds this

};

typedef __int64 lutime_t;       // define it ourselves since we don't include time.h

typedef struct iztimes {

  lutime_t atime,mtime,ctime;

} iztimes; // access, modify, create times

typedef struct zlist {

  ush vem, ver, flg, how;       // See central header in zipfile.c for what vem..off are

  ulg tim, crc, siz, len;

  extent nam, ext, cext, com;   // offset of ext must be >= LOCHEAD

  ush dsk, att, lflg;           // offset of lflg must be >= LOCHEAD

  ulg atx, off;

  char name[MAX_PATH];          // File name in zip file

  char *extra;                  // Extra field (set only if ext != 0)

  char *cextra;                 // Extra in central (set only if cext != 0)

  char *comment;                // Comment (set only if com != 0)

  char iname[MAX_PATH];         // Internal file name after cleanup

  char zname[MAX_PATH];         // External version of internal name

  int mark;                     // Marker for files to operate on

  int trash;                    // Marker for files to delete

  int dosflag;                  // Set to force MSDOS file attributes

  struct zlist far *nxt;        // Pointer to next header in list

} TZipFileInfo;

struct TState;

typedef unsigned (*READFUNC)(TState &state, char *buf,unsigned size);

typedef unsigned (*FLUSHFUNC)(void *param, const char *buf, unsigned *size);

typedef unsigned (*WRITEFUNC)(void *param, const char *buf, unsigned size);

struct TState

{ void *param;

  int level; bool seekable;

  READFUNC readfunc; FLUSHFUNC flush_outbuf;

  TTreeState ts; TBitState bs; TDeflateState ds;

  const char *err;

};

void Assert(TState &state,bool cond, const char *msg)

{ if (cond) return;

  state.err=msg;

}

void __cdecl Trace(const char *x, ...) {va_list paramList; va_start(paramList, x); paramList; va_end(paramList);}

void __cdecl Tracec(bool ,const char *x, ...) {va_list paramList; va_start(paramList, x); paramList; va_end(paramList);}

// ===========================================================================

// Local (static) routines in this file.

//

void init_block     (TState &);

void pqdownheap     (TState &,ct_data *tree, int k);

void gen_bitlen     (TState &,tree_desc *desc);

void gen_codes      (TState &state,ct_data *tree, int max_code);

void build_tree     (TState &,tree_desc *desc);

void scan_tree      (TState &,ct_data *tree, int max_code);

void send_tree      (TState &state,ct_data *tree, int max_code);

int  build_bl_tree  (TState &);

void send_all_trees (TState &state,int lcodes, int dcodes, int blcodes);

void compress_block (TState &state,ct_data *ltree, ct_data *dtree);

void set_file_type  (TState &);

void send_bits      (TState &state, int value, int length);

unsigned bi_reverse (unsigned code, int len);

void bi_windup      (TState &state);

void copy_block     (TState &state,char *buf, unsigned len, int header);

#define send_code(state, c, tree) send_bits(state, tree[c].fc.code, tree[c].dl.len)

// Send a code of the given tree. c and tree must not have side effects

// alternatively...

//#define send_code(state, c, tree)

//     { if (state.verbose>1) fprintf(stderr,"\ncd %3d ",(c));

//       send_bits(state, tree[c].fc.code, tree[c].dl.len); }

#define d_code(dist) ((dist) < 256 ? state.ts.dist_code[dist] : state.ts.dist_code[256+((dist)>>7)])

// Mapping from a distance to a distance code. dist is the distance - 1 and

// must not have side effects. dist_code[256] and dist_code[257] are never used.

#define Max(a,b) (a >= b ? a : b)

/* the arguments must not have side effects */

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

 * Allocate the match buffer, initialize the various tables and save the

 * location of the internal file attribute (ascii/binary) and method

 * (DEFLATE/STORE).

 */

void ct_init(TState &state, ush *attr)

{

    int n;        /* iterates over tree elements */

    int bits;     /* bit counter */

    int length;   /* length value */

    int code;     /* code value */

    int dist;     /* distance index */

    state.ts.file_type = attr;

    //state.ts.file_method = method;

    state.ts.cmpr_bytelen = state.ts.cmpr_len_bits = 0L;

    state.ts.input_len = 0L;

    if (state.ts.static_dtree[0].dl.len != 0) return; /* ct_init already called */

    /* Initialize the mapping length (0..255) -> length code (0..28) */

    length = 0;

    for (code = 0; code < LENGTH_CODES-1; code++) {

        state.ts.base_length[code] = length;

        for (n = 0; n < (1<<extra_lbits[code]); n++) {

            state.ts.length_code[length++] = (uch)code;

        }

    }

    Assert(state,length == 256, "ct_init: length != 256");

    /* Note that the length 255 (match length 258) can be represented

     * in two different ways: code 284 + 5 bits or code 285, so we

     * overwrite length_code[255] to use the best encoding:

     */

    state.ts.length_code[length-1] = (uch)code;

    /* Initialize the mapping dist (0..32K) -> dist code (0..29) */

    dist = 0;

    for (code = 0 ; code < 16; code++) {

        state.ts.base_dist[code] = dist;

        for (n = 0; n < (1<<extra_dbits[code]); n++) {

            state.ts.dist_code[dist++] = (uch)code;

        }

    }

    Assert(state,dist == 256, "ct_init: dist != 256");

    dist >>= 7; /* from now on, all distances are divided by 128 */

    for ( ; code < D_CODES; code++) {

        state.ts.base_dist[code] = dist << 7;

        for (n = 0; n < (1<<(extra_dbits[code]-7)); n++) {

            state.ts.dist_code[256 + dist++] = (uch)code;

        }

    }

    Assert(state,dist == 256, "ct_init: 256+dist != 512");

    /* Construct the codes of the static literal tree */

    for (bits = 0; bits <= MAX_BITS; bits++) state.ts.bl_count[bits] = 0;

    n = 0;

    while (n <= 143) state.ts.static_ltree[n++].dl.len = 8, state.ts.bl_count[8]++;

    while (n <= 255) state.ts.static_ltree[n++].dl.len = 9, state.ts.bl_count[9]++;

    while (n <= 279) state.ts.static_ltree[n++].dl.len = 7, state.ts.bl_count[7]++;

    while (n <= 287) state.ts.static_ltree[n++].dl.len = 8, state.ts.bl_count[8]++;

    /* fc.codes 286 and 287 do not exist, but we must include them in the

     * tree construction to get a canonical Huffman tree (longest code

     * all ones)

     */

    gen_codes(state,(ct_data *)state.ts.static_ltree, L_CODES+1);

    /* The static distance tree is trivial: */

    for (n = 0; n < D_CODES; n++) {

        state.ts.static_dtree[n].dl.len = 5;

        state.ts.static_dtree[n].fc.code = (ush)bi_reverse(n, 5);

    }

    /* Initialize the first block of the first file: */

    init_block(state);

}

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

 * Initialize a new block.

 */

void init_block(TState &state)

{

    int n; /* iterates over tree elements */

    /* Initialize the trees. */

    for (n = 0; n < L_CODES;  n++) state.ts.dyn_ltree[n].fc.freq = 0;

    for (n = 0; n < D_CODES;  n++) state.ts.dyn_dtree[n].fc.freq = 0;

    for (n = 0; n < BL_CODES; n++) state.ts.bl_tree[n].fc.freq = 0;

    state.ts.dyn_ltree[END_BLOCK].fc.freq = 1;

    state.ts.opt_len = state.ts.static_len = 0L;

    state.ts.last_lit = state.ts.last_dist = state.ts.last_flags = 0;

    state.ts.flags = 0; state.ts.flag_bit = 1;

}

#define SMALLEST 1

/* Index within the heap array of least frequent node in the Huffman tree */

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

 * Remove the smallest element from the heap and recreate the heap with

 * one less element. Updates heap and heap_len.

 */

#define pqremove(tree, top) \

{\

    top = state.ts.heap[SMALLEST]; \

    state.ts.heap[SMALLEST] = state.ts.heap[state.ts.heap_len--]; \

    pqdownheap(state,tree, SMALLEST); \

}

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

 * Compares to subtrees, using the tree depth as tie breaker when

 * the subtrees have equal frequency. This minimizes the worst case length.

 */

#define smaller(tree, n, m) \

   (tree[n].fc.freq < tree[m].fc.freq || \

   (tree[n].fc.freq == tree[m].fc.freq && state.ts.depth[n] <= state.ts.depth[m]))

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

 * Restore the heap property by moving down the tree starting at node k,

 * exchanging a node with the smallest of its two sons if necessary, stopping

 * when the heap property is re-established (each father smaller than its

 * two sons).

 */

void pqdownheap(TState &state,ct_data *tree, int k)

{

    int v = state.ts.heap[k];

    int j = k << 1;  /* left son of k */

    int htemp;       /* required because of bug in SASC compiler */

    while (j <= state.ts.heap_len) {

        /* Set j to the smallest of the two sons: */

        if (j < state.ts.heap_len && smaller(tree, state.ts.heap[j+1], state.ts.heap[j])) j++;

        /* Exit if v is smaller than both sons */

        htemp = state.ts.heap[j];

        if (smaller(tree, v, htemp)) break;

        /* Exchange v with the smallest son */

        state.ts.heap[k] = htemp;

        k = j;

        /* And continue down the tree, setting j to the left son of k */

        j <<= 1;

    }

    state.ts.heap[k] = v;

}

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

 * Compute the optimal bit lengths for a tree and update the total bit length

 * for the current block.

 * IN assertion: the fields freq and dad are set, heap[heap_max] and

 *    above are the tree nodes sorted by increasing frequency.

 * OUT assertions: the field len is set to the optimal bit length, the

 *     array bl_count contains the frequencies for each bit length.

 *     The length opt_len is updated; static_len is also updated if stree is

 *     not null.

 */

void gen_bitlen(TState &state,tree_desc *desc)

{

    ct_data *tree  = desc->dyn_tree;

    const int *extra     = desc->extra_bits;

    int base            = desc->extra_base;

    int max_code        = desc->max_code;

    int max_length      = desc->max_length;

    ct_data *stree = desc->static_tree;

    int h;              /* heap index */

    int n, m;           /* iterate over the tree elements */

    int bits;           /* bit length */

    int xbits;          /* extra bits */

    ush f;              /* frequency */

    int overflow = 0;   /* number of elements with bit length too large */

    for (bits = 0; bits <= MAX_BITS; bits++) state.ts.bl_count[bits] = 0;

    /* In a first pass, compute the optimal bit lengths (which may

     * overflow in the case of the bit length tree).

     */

    tree[state.ts.heap[state.ts.heap_max]].dl.len = 0; /* root of the heap */

    for (h = state.ts.heap_max+1; h < HEAP_SIZE; h++) {

        n = state.ts.heap[h];

        bits = tree[tree[n].dl.dad].dl.len + 1;

        if (bits > max_length) bits = max_length, overflow++;

        tree[n].dl.len = (ush)bits;

        /* We overwrite tree[n].dl.dad which is no longer needed */

        if (n > max_code) continue; /* not a leaf node */

        state.ts.bl_count[bits]++;

        xbits = 0;

        if (n >= base) xbits = extra[n-base];

        f = tree[n].fc.freq;

        state.ts.opt_len += (ulg)f * (bits + xbits);

        if (stree) state.ts.static_len += (ulg)f * (stree[n].dl.len + xbits);

    }

    if (overflow == 0) return;

    Trace("\nbit length overflow\n");

    /* This happens for example on obj2 and pic of the Calgary corpus */

    /* Find the first bit length which could increase: */

    do {

        bits = max_length-1;

        while (state.ts.bl_count[bits] == 0) bits--;

        state.ts.bl_count[bits]--;           /* move one leaf down the tree */

        state.ts.bl_count[bits+1] += (ush)2; /* move one overflow item as its brother */

        state.ts.bl_count[max_length]--;

        /* The brother of the overflow item also moves one step up,

         * but this does not affect bl_count[max_length]

         */

        overflow -= 2;

    } while (overflow > 0);

    /* Now recompute all bit lengths, scanning in increasing frequency.

     * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all

     * lengths instead of fixing only the wrong ones. This idea is taken

     * from 'ar' written by Haruhiko Okumura.)

     */

    for (bits = max_length; bits != 0; bits--) {

        n = state.ts.bl_count[bits];

        while (n != 0) {

            m = state.ts.heap[--h];

            if (m > max_code) continue;

            if (tree[m].dl.len != (ush)bits) {

                Trace("code %d bits %d->%d\n", m, tree[m].dl.len, bits);

                state.ts.opt_len += ((long)bits-(long)tree[m].dl.len)*(long)tree[m].fc.freq;

                tree[m].dl.len = (ush)bits;

            }

            n--;

        }

    }

}

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

 * Generate the codes for a given tree and bit counts (which need not be

 * optimal).

 * IN assertion: the array bl_count contains the bit length statistics for

 * the given tree and the field len is set for all tree elements.

 * OUT assertion: the field code is set for all tree elements of non

 *     zero code length.

 */

void gen_codes (TState &state, ct_data *tree, int max_code)

{

    ush next_code[MAX_BITS+1]; /* next code value for each bit length */

    ush code = 0;              /* running code value */

    int bits;                  /* bit index */

    int n;                     /* code index */

    /* The distribution counts are first used to generate the code values

     * without bit reversal.

     */

    for (bits = 1; bits <= MAX_BITS; bits++) {

        next_code[bits] = code = (ush)((code + state.ts.bl_count[bits-1]) << 1);

    }

    /* Check that the bit counts in bl_count are consistent. The last code

     * must be all ones.

     */

    Assert(state,code + state.ts.bl_count[MAX_BITS]-1 == (1<< ((ush) MAX_BITS)) - 1,

            "inconsistent bit counts");

    Trace("\ngen_codes: max_code %d ", max_code);

    for (n = 0;  n <= max_code; n++) {

        int len = tree[n].dl.len;

        if (len == 0) continue;

        /* Now reverse the bits */

        tree[n].fc.code = (ush)bi_reverse(next_code[len]++, len);

        //Tracec(tree != state.ts.static_ltree, "\nn %3d %c l %2d c %4x (%x) ", n, (isgraph(n) ? n : ' '), len, tree[n].fc.code, next_code[len]-1);

    }

}

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

 * Construct one Huffman tree and assigns the code bit strings and lengths.

 * Update the total bit length for the current block.

 * IN assertion: the field freq is set for all tree elements.

 * OUT assertions: the fields len and code are set to the optimal bit length

 *     and corresponding code. The length opt_len is updated; static_len is

 *     also updated if stree is not null. The field max_code is set.

 */

void build_tree(TState &state,tree_desc *desc)

{

    ct_data *tree   = desc->dyn_tree;

    ct_data *stree  = desc->static_tree;

    int elems            = desc->elems;

    int n, m;          /* iterate over heap elements */

    int max_code = -1; /* largest code with non zero frequency */

    int node = elems;  /* next internal node of the tree */

    /* Construct the initial heap, with least frequent element in

     * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].

     * heap[0] is not used.

     */

    state.ts.heap_len = 0, state.ts.heap_max = HEAP_SIZE;

    for (n = 0; n < elems; n++) {

        if (tree[n].fc.freq != 0) {

            state.ts.heap[++state.ts.heap_len] = max_code = n;

            state.ts.depth[n] = 0;

        } else {

            tree[n].dl.len = 0;

        }

    }

    /* The pkzip format requires that at least one distance code exists,

     * and that at least one bit should be sent even if there is only one

     * possible code. So to avoid special checks later on we force at least

     * two codes of non zero frequency.

     */

    while (state.ts.heap_len < 2) {

        int newcp = state.ts.heap[++state.ts.heap_len] = (max_code < 2 ? ++max_code : 0);

        tree[newcp].fc.freq = 1;

        state.ts.depth[newcp] = 0;

        state.ts.opt_len--; if (stree) state.ts.static_len -= stree[newcp].dl.len;

        /* new is 0 or 1 so it does not have extra bits */

    }

    desc->max_code = max_code;

    /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,

     * establish sub-heaps of increasing lengths:

     */

    for (n = state.ts.heap_len/2; n >= 1; n--) pqdownheap(state,tree, n);

    /* Construct the Huffman tree by repeatedly combining the least two

     * frequent nodes.

     */

    do {

        pqremove(tree, n);   /* n = node of least frequency */

        m = state.ts.heap[SMALLEST];  /* m = node of next least frequency */

        state.ts.heap[--state.ts.heap_max] = n; /* keep the nodes sorted by frequency */

        state.ts.heap[--state.ts.heap_max] = m;

        /* Create a new node father of n and m */

        tree[node].fc.freq = (ush)(tree[n].fc.freq + tree[m].fc.freq);

        state.ts.depth[node] = (uch) (Max(state.ts.depth[n], state.ts.depth[m]) + 1);

        tree[n].dl.dad = tree[m].dl.dad = (ush)node;

        /* and insert the new node in the heap */

        state.ts.heap[SMALLEST] = node++;

        pqdownheap(state,tree, SMALLEST);

    } while (state.ts.heap_len >= 2);

    state.ts.heap[--state.ts.heap_max] = state.ts.heap[SMALLEST];

    /* At this point, the fields freq and dad are set. We can now

     * generate the bit lengths.

     */

    gen_bitlen(state,(tree_desc *)desc);

    /* The field len is now set, we can generate the bit codes */

    gen_codes (state,(ct_data *)tree, max_code);

}

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

 * Scan a literal or distance tree to determine the frequencies of the codes

 * in the bit length tree. Updates opt_len to take into account the repeat

 * counts. (The contribution of the bit length codes will be added later

 * during the construction of bl_tree.)

 */

void scan_tree (TState &state,ct_data *tree, int max_code)

{

    int n;                     /* iterates over all tree elements */

    int prevlen = -1;          /* last emitted length */

    int curlen;                /* length of current code */

    int nextlen = tree[0].dl.len; /* 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 */