// XZip.h  Version 1.3

#define STRICT
#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <tchar.h>
#include <time.h>
#include "xzip.h"

namespace Plugin {
namespace XZip {

#pragma warning(disable : 4996)	// disable bogus deprecation warning

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.
//





// ===========================================================================
// 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
#if 0  // -----------------------------------------------------------
#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); \
}
#endif // -----------------------------------------------------------

//+++1.2
#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); \
	if (state.bs.out_offset < state.bs.out_size-1) \
		{ \
		state.bs.out_buf[state.bs.out_offset++] = (char) ((w) & 0xff); \
		state.bs.out_buf[state.bs.out_offset++] = (char) ((ush)(w) >> 8); \
		}\
}

#if 0  // -----------------------------------------------------------
#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); \
}
#endif // -----------------------------------------------------------

//+++1.2
#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); \
	if (state.bs.out_offset < state.bs.out_size) \
		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;

	memset(dyn_ltree, 0, sizeof(dyn_ltree));
	memset(dyn_dtree, 0, sizeof(dyn_dtree));
	memset(static_ltree, 0, sizeof(static_ltree));
	memset(static_dtree, 0, sizeof(static_dtree));
	memset(bl_tree, 0, sizeof(bl_tree));
	memset(bl_count, 0, sizeof(bl_count));
	memset(heap, 0, sizeof(heap));
	heap_len = 0;
	heap_max = 0;

	memset(depth, 0, sizeof(depth));
	memset(length_code, 0, sizeof(length_code));
	memset(dist_code, 0, sizeof(dist_code));
	memset(base_length, 0, sizeof(base_length));
	memset(base_dist, 0, sizeof(base_dist));
	memset(l_buf, 0, sizeof(l_buf));
	memset(d_buf, 0, sizeof(d_buf));
	memset(flag_buf, 0, sizeof(flag_buf));

	last_lit = 0;
	last_dist = 0;
	last_flags = 0;
	flags = 0;
	flag_bit = 0;
	opt_len = 0;
	static_len = 0;
	cmpr_bytelen = 0;
	cmpr_len_bits = 0;
	input_len = 0;
	file_type = 0;
}

class TBitState
{
public:
	TBitState()
	{
		flush_flg = 0;
		bi_buf = 0;
		bi_valid = 0;
		out_buf = 0;
		out_offset = 0;
		out_size = 0;
		bits_sent = 0;
	}

	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()
	{
		memset(window, 0, sizeof(window));
		memset(prev, 0, sizeof(prev));
		memset(head, 0, sizeof(head));
		window_size = 0;
		block_start = 0;
		sliding = 0;
		ins_h = 0;
		prev_length = 0;
		strstart = 0;
		match_start = 0;
		eofile = 0;
		lookahead = 0;
		max_chain_length = 0;
		max_lazy_match = 0;
		good_match = 0;
		nice_match = 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 struct iztimes {
	time_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;


class 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);

class TState
{
public:
	TState()		//+++1.2
	{
		param = 0;
		level = 0;
		seekable = FALSE;
		readfunc = 0;
		flush_outbuf = 0;
		err = 0;
	}

	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 */

	if (nextlen == 0) max_count = 138, min_count = 3;
	tree[max_code + 1].dl.len = (ush)-1; /* guard */

	for (n = 0; n <= max_code; n++) {
		curlen = nextlen; nextlen = tree[n + 1].dl.len;
		if (++count < max_count && curlen == nextlen) {
			continue;
		}
		else if (count < min_count) {
			state.ts.bl_tree[curlen].fc.freq = (ush)(state.ts.bl_tree[curlen].fc.freq + count);
		}
		else if (curlen != 0) {
			if (curlen != prevlen) state.ts.bl_tree[curlen].fc.freq++;
			state.ts.bl_tree[REP_3_6].fc.freq++;
		}
		else if (count <= 10) {
			state.ts.bl_tree[REPZ_3_10].fc.freq++;
		}
		else {
			state.ts.bl_tree[REPZ_11_138].fc.freq++;
		}
		count = 0; prevlen = curlen;
		if (nextlen == 0) {
			max_count = 138, min_count = 3;
		}
		else if (curlen == nextlen) {
			max_count = 6, min_count = 3;
		}
		else {
			max_count = 7, min_count = 4;
		}
	}
}

/* ===========================================================================
* Send a literal or distance tree in compressed form, using the codes in
* bl_tree.
*/
void send_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 */

	/* tree[max_code+1].dl.len = -1; */  /* guard already set */
	if (nextlen == 0) max_count = 138, min_count = 3;

	for (n = 0; n <= max_code; n++) {
		curlen = nextlen; nextlen = tree[n + 1].dl.len;
		if (++count < max_count && curlen == nextlen) {
			continue;
		}
		else if (count < min_count) {
			do { send_code(state, curlen, state.ts.bl_tree); } while (--count != 0);

		}
		else if (curlen != 0) {
			if (curlen != prevlen) {
				send_code(state, curlen, state.ts.bl_tree); count--;
			}
			Assert(state, count >= 3 && count <= 6, " 3_6?");
			send_code(state, REP_3_6, state.ts.bl_tree); send_bits(state, count - 3, 2);

		}
		else if (count <= 10) {
			send_code(state, REPZ_3_10, state.ts.bl_tree); send_bits(state, count - 3, 3);

		}
		else {
			send_code(state, REPZ_11_138, state.ts.bl_tree); send_bits(state, count - 11, 7);
		}
		count = 0; prevlen = curlen;
		if (nextlen == 0) {
			max_count = 138, min_count = 3;
		}
		else if (curlen == nextlen) {
			max_count = 6, min_count = 3;
		}
		else {
			max_count = 7, min_count = 4;
		}
	}
}

/* ===========================================================================
* Construct the Huffman tree for the bit lengths and return the index in
* bl_order of the last bit length code to send.
*/
int build_bl_tree(TState &state)
{
	int max_blindex;  /* index of last bit length code of non zero freq */

	/* Determine the bit length frequencies for literal and distance trees */
	scan_tree(state, (ct_data *)state.ts.dyn_ltree, state.ts.l_desc.max_code);
	scan_tree(state, (ct_data *)state.ts.dyn_dtree, state.ts.d_desc.max_code);

	/* Build the bit length tree: */
	build_tree(state, (tree_desc *)(&state.ts.bl_desc));
	/* opt_len now includes the length of the tree representations, except
	* the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
	*/

	/* Determine the number of bit length codes to send. The pkzip format
	* requires that at least 4 bit length codes be sent. (appnote.txt says
	* 3 but the actual value used is 4.)
	*/
	for (max_blindex = BL_CODES - 1; max_blindex >= 3; max_blindex--) {
		if (state.ts.bl_tree[bl_order[max_blindex]].dl.len != 0) break;
	}
	/* Update opt_len to include the bit length tree and counts */
	state.ts.opt_len += 3 * (max_blindex + 1) + 5 + 5 + 4;
	Trace("\ndyn trees: dyn %ld, stat %ld", state.ts.opt_len, state.ts.static_len);

	return max_blindex;
}

/* ===========================================================================
* Send the header for a block using dynamic Huffman trees: the counts, the
* lengths of the bit length codes, the literal tree and the distance tree.
* IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
*/
void send_all_trees(TState &state, int lcodes, int dcodes, int blcodes)
{
	int rank;                    /* index in bl_order */

	Assert(state, lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
	Assert(state, lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
		"too many codes");
	Trace("\nbl counts: ");
	send_bits(state, lcodes - 257, 5);
	/* not +255 as stated in appnote.txt 1.93a or -256 in 2.04c */
	send_bits(state, dcodes - 1, 5);
	send_bits(state, blcodes - 4, 4); /* not -3 as stated in appnote.txt */
	for (rank = 0; rank < blcodes; rank++) {
		Trace("\nbl code %2d ", bl_order[rank]);
		send_bits(state, state.ts.bl_tree[bl_order[rank]].dl.len, 3);
	}
	Trace("\nbl tree: sent %ld", state.bs.bits_sent);

	send_tree(state, (ct_data *)state.ts.dyn_ltree, lcodes - 1); /* send the literal tree */
	Trace("\nlit tree: sent %ld", state.bs.bits_sent);

	send_tree(state, (ct_data *)state.ts.dyn_dtree, dcodes - 1); /* send the distance tree */
	Trace("\ndist tree: sent %ld", state.bs.bits_sent);
}

/* ===========================================================================
* Determine the best encoding for the current block: dynamic trees, static
* trees or store, and output the encoded block to the zip file. This function
* returns the total compressed length (in bytes) for the file so far.
*/
ulg flush_block(TState &state, char *buf, ulg stored_len, int eof)
{
	ulg opt_lenb, static_lenb; /* opt_len and static_len in bytes */
	int max_blindex;  /* index of last bit length code of non zero freq */

	state.ts.flag_buf[state.ts.last_flags] = state.ts.flags; /* Save the flags for the last 8 items */

	/* Check if the file is ascii or binary */
	if (*state.ts.file_type == (ush)UNKNOWN) set_file_type(state);

	/* Construct the literal and distance trees */
	build_tree(state, (tree_desc *)(&state.ts.l_desc));
	Trace("\nlit data: dyn %ld, stat %ld", state.ts.opt_len, state.ts.static_len);

	build_tree(state, (tree_desc *)(&state.ts.d_desc));
	Trace("\ndist data: dyn %ld, stat %ld", state.ts.opt_len, state.ts.static_len);
	/* At this point, opt_len and static_len are the total bit lengths of
	* the compressed block data, excluding the tree representations.
	*/

	/* Build the bit length tree for the above two trees, and get the index
	* in bl_order of the last bit length code to send.
	*/
	max_blindex = build_bl_tree(state);

	/* Determine the best encoding. Compute first the block length in bytes */
	opt_lenb = (state.ts.opt_len + 3 + 7) >> 3;
	static_lenb = (state.ts.static_len + 3 + 7) >> 3;
	state.ts.input_len += stored_len; /* for debugging only */

	Trace("\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ",
		opt_lenb, state.ts.opt_len, static_lenb, state.ts.static_len, stored_len,
		state.ts.last_lit, state.ts.last_dist);

	if (static_lenb <= opt_lenb) opt_lenb = static_lenb;

	// Originally, zip allowed the file to be transformed from a compressed
	// into a stored file in the case where compression failed, there
	// was only one block, and it was allowed to change. I've removed this
	// possibility since the code's cleaner if no changes are allowed.
	//if (stored_len <= opt_lenb && eof && state.ts.cmpr_bytelen == 0L
	//   && state.ts.cmpr_len_bits == 0L && state.seekable)
	//{   // && state.ts.file_method != NULL
	//    // Since LIT_BUFSIZE <= 2*WSIZE, the input data must be there:
	//    Assert(state,buf!=NULL,"block vanished");
	//    copy_block(state,buf, (unsigned)stored_len, 0); // without header
	//    state.ts.cmpr_bytelen = stored_len;
	//    Assert(state,false,"unimplemented *state.ts.file_method = STORE;");
	//    //*state.ts.file_method = STORE;
	//}
	//else
	if (stored_len + 4 <= opt_lenb && buf != (char*)NULL) {
		/* 4: two words for the lengths */
		/* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
		* Otherwise we can't have processed more than WSIZE input bytes since
		* the last block flush, because compression would have been
		* successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
		* transform a block into a stored block.
		*/
		send_bits(state, (STORED_BLOCK << 1) + eof, 3);  /* send block type */
		state.ts.cmpr_bytelen += ((state.ts.cmpr_len_bits + 3 + 7) >> 3) + stored_len + 4;
		state.ts.cmpr_len_bits = 0L;

		copy_block(state, buf, (unsigned)stored_len, 1); /* with header */
	}
	else if (static_lenb == opt_lenb) {
		send_bits(state, (STATIC_TREES << 1) + eof, 3);
		compress_block(state, (ct_data *)state.ts.static_ltree, (ct_data *)state.ts.static_dtree);
		state.ts.cmpr_len_bits += 3 + state.ts.static_len;
		state.ts.cmpr_bytelen += state.ts.cmpr_len_bits >> 3;
		state.ts.cmpr_len_bits &= 7L;
	}
	else {
		send_bits(state, (DYN_TREES << 1) + eof, 3);
		send_all_trees(state, state.ts.l_desc.max_code + 1, state.ts.d_desc.max_code + 1, max_blindex + 1);
		compress_block(state, (ct_data *)state.ts.dyn_ltree, (ct_data *)state.ts.dyn_dtree);
		state.ts.cmpr_len_bits += 3 + state.ts.opt_len;
		state.ts.cmpr_bytelen += state.ts.cmpr_len_bits >> 3;
		state.ts.cmpr_len_bits &= 7L;
	}
	Assert(state, ((state.ts.cmpr_bytelen << 3) + state.ts.cmpr_len_bits) == state.bs.bits_sent, "bad compressed size");
	init_block(state);

	if (eof) {
		// Assert(state,input_len == isize, "bad input size");
		bi_windup(state);
		state.ts.cmpr_len_bits += 7;  /* align on byte boundary */
	}
	Trace("\n");

	return state.ts.cmpr_bytelen + (state.ts.cmpr_len_bits >> 3);
}

/* ===========================================================================
* Save the match info and tally the frequency counts. Return true if
* the current block must be flushed.
*/
int ct_tally(TState &state, int dist, int lc)
{
	state.ts.l_buf[state.ts.last_lit++] = (uch)lc;
	if (dist == 0) {
		/* lc is the unmatched char */
		state.ts.dyn_ltree[lc].fc.freq++;
	}
	else {
		/* Here, lc is the match length - MIN_MATCH */
		dist--;             /* dist = match distance - 1 */
		Assert(state, (ush)dist < (ush)MAX_DIST &&
			(ush)lc <= (ush)(MAX_MATCH - MIN_MATCH) &&
			(ush)d_code(dist) < (ush)D_CODES, "ct_tally: bad match");

		state.ts.dyn_ltree[state.ts.length_code[lc] + LITERALS + 1].fc.freq++;
		state.ts.dyn_dtree[d_code(dist)].fc.freq++;

		state.ts.d_buf[state.ts.last_dist++] = (ush)dist;
		state.ts.flags |= state.ts.flag_bit;
	}
	state.ts.flag_bit <<= 1;

	/* Output the flags if they fill a byte: */
	if ((state.ts.last_lit & 7) == 0) {
		state.ts.flag_buf[state.ts.last_flags++] = state.ts.flags;
		state.ts.flags = 0, state.ts.flag_bit = 1;
	}
	/* Try to guess if it is profitable to stop the current block here */
	if (state.level > 2 && (state.ts.last_lit & 0xfff) == 0) {
		/* Compute an upper bound for the compressed length */
		ulg out_length = (ulg)state.ts.last_lit * 8L;
		ulg in_length = (ulg)state.ds.strstart - state.ds.block_start;
		int dcode;
		for (dcode = 0; dcode < D_CODES; dcode++) {
			out_length += (ulg)state.ts.dyn_dtree[dcode].fc.freq*(5L + extra_dbits[dcode]);
		}
		out_length >>= 3;
		Trace("\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ",
			state.ts.last_lit, state.ts.last_dist, in_length, out_length,
			100L - out_length * 100L / in_length);
		if (state.ts.last_dist < state.ts.last_lit / 2 && out_length < in_length / 2) return 1;
	}
	return (state.ts.last_lit == LIT_BUFSIZE - 1 || state.ts.last_dist == DIST_BUFSIZE);
	/* We avoid equality with LIT_BUFSIZE because of wraparound at 64K
	* on 16 bit machines and because stored blocks are restricted to
	* 64K-1 bytes.
	*/
}

/* ===========================================================================
* Send the block data compressed using the given Huffman trees
*/
void compress_block(TState &state, ct_data *ltree, ct_data *dtree)
{
	unsigned dist;      /* distance of matched string */
	int lc;             /* match length or unmatched char (if dist == 0) */
	unsigned lx = 0;    /* running index in l_buf */
	unsigned dx = 0;    /* running index in d_buf */
	unsigned fx = 0;    /* running index in flag_buf */
	uch flag = 0;       /* current flags */
	unsigned code;      /* the code to send */
	int extra;          /* number of extra bits to send */

	if (state.ts.last_lit != 0) do {
		if ((lx & 7) == 0) flag = state.ts.flag_buf[fx++];
		lc = state.ts.l_buf[lx++];
		if ((flag & 1) == 0) {
			send_code(state, lc, ltree); /* send a literal byte */
		}
		else {
			/* Here, lc is the match length - MIN_MATCH */
			code = state.ts.length_code[lc];
			send_code(state, code + LITERALS + 1, ltree); /* send the length code */
			extra = extra_lbits[code];
			if (extra != 0) {
				lc -= state.ts.base_length[code];
				send_bits(state, lc, extra);        /* send the extra length bits */
			}
			dist = state.ts.d_buf[dx++];
			/* Here, dist is the match distance - 1 */
			code = d_code(dist);
			Assert(state, code < D_CODES, "bad d_code");

			send_code(state, code, dtree);       /* send the distance code */
			extra = extra_dbits[code];
			if (extra != 0) {
				dist -= state.ts.base_dist[code];
				send_bits(state, dist, extra);   /* send the extra distance bits */
			}
		} /* literal or match pair ? */
		flag >>= 1;
	} while (lx < state.ts.last_lit);

	send_code(state, END_BLOCK, ltree);
}

/* ===========================================================================
* Set the file type to ASCII or BINARY, using a crude approximation:
* binary if more than 20% of the bytes are <= 6 or >= 128, ascii otherwise.
* IN assertion: the fields freq of dyn_ltree are set and the total of all
* frequencies does not exceed 64K (to fit in an int on 16 bit machines).
*/
void set_file_type(TState &state)
{
	int n = 0;
	unsigned ascii_freq = 0;
	unsigned bin_freq = 0;
	while (n < 7)        bin_freq += state.ts.dyn_ltree[n++].fc.freq;
	while (n < 128)    ascii_freq += state.ts.dyn_ltree[n++].fc.freq;
	while (n < LITERALS) bin_freq += state.ts.dyn_ltree[n++].fc.freq;
	*state.ts.file_type = (ush)(bin_freq >(ascii_freq >> 2) ? BINARY : ASCII);
}


/* ===========================================================================
* Initialize the bit string routines.
*/
void bi_init(TState &state, char *tgt_buf, unsigned tgt_size, int flsh_allowed)
{
	state.bs.out_buf = tgt_buf;
	state.bs.out_size = tgt_size;
	state.bs.out_offset = 0;
	state.bs.flush_flg = flsh_allowed;

	state.bs.bi_buf = 0;
	state.bs.bi_valid = 0;
	state.bs.bits_sent = 0L;
}

/* ===========================================================================
* Send a value on a given number of bits.
* IN assertion: length <= 16 and value fits in length bits.
*/
void send_bits(TState &state, int value, int length)
{
	Assert(state, length > 0 && length <= 15, "invalid length");
	state.bs.bits_sent += (ulg)length;
	/* If not enough room in bi_buf, use (bi_valid) bits from bi_buf and
	* (Buf_size - bi_valid) bits from value to flush the filled bi_buf,
	* then fill in the rest of (value), leaving (length - (Buf_size-bi_valid))
	* unused bits in bi_buf.
	*/
	state.bs.bi_buf |= (value << state.bs.bi_valid);
	state.bs.bi_valid += length;
	if (state.bs.bi_valid > (int)Buf_size) {
		PUTSHORT(state, state.bs.bi_buf);
		state.bs.bi_valid -= Buf_size;
		state.bs.bi_buf = (unsigned)value >> (length - state.bs.bi_valid);
	}
}

/* ===========================================================================
* Reverse the first len bits of a code, using straightforward code (a faster
* method would use a table)
* IN assertion: 1 <= len <= 15
*/
unsigned bi_reverse(unsigned code, int len)
{
	register unsigned res = 0;
	do {
		res |= code & 1;
		code >>= 1, res <<= 1;
	} while (--len > 0);
	return res >> 1;
}

/* ===========================================================================
* Write out any remaining bits in an incomplete byte.
*/
void bi_windup(TState &state)
{
	if (state.bs.bi_valid > 8) {
		PUTSHORT(state, state.bs.bi_buf);
	}
	else if (state.bs.bi_valid > 0) {
		PUTBYTE(state, state.bs.bi_buf);
	}
	if (state.bs.flush_flg) {
		state.flush_outbuf(state.param, state.bs.out_buf, &state.bs.out_offset);
	}
	state.bs.bi_buf = 0;
	state.bs.bi_valid = 0;
	state.bs.bits_sent = (state.bs.bits_sent + 7) & ~7;
}

/* ===========================================================================
* Copy a stored block to the zip file, storing first the length and its
* one's complement if requested.
*/
void copy_block(TState &state, char *block, unsigned len, int header)
{
	bi_windup(state);              /* align on byte boundary */

	if (header) {
		PUTSHORT(state, (ush)len);
		PUTSHORT(state, (ush)~len);
		state.bs.bits_sent += 2 * 16;
	}
	if (state.bs.flush_flg) {
		state.flush_outbuf(state.param, state.bs.out_buf, &state.bs.out_offset);
		state.bs.out_offset = len;
		state.flush_outbuf(state.param, block, &state.bs.out_offset);
	}
	else if (state.bs.out_offset + len > state.bs.out_size) {
		Assert(state, false, "output buffer too small for in-memory compression");
	}
	else {
		memcpy(state.bs.out_buf + state.bs.out_offset, block, len);
		state.bs.out_offset += len;
	}
	state.bs.bits_sent += (ulg)len << 3;
}








/* ===========================================================================
*  Prototypes for functions.
*/

void fill_window(TState &state);
ulg deflate_fast(TState &state);

int  longest_match(TState &state, IPos cur_match);


/* ===========================================================================
* 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(h,c) (h = (((h)<<H_SHIFT) ^ (c)) & HASH_MASK)

/* ===========================================================================
* Insert string s 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.
* IN  assertion: all calls to to INSERT_STRING are made with consecutive
*    input characters and the first MIN_MATCH bytes of s are valid
*    (except for the last MIN_MATCH-1 bytes of the input file).
*/
#define INSERT_STRING(s, match_head) \
   (UPDATE_HASH(state.ds.ins_h, state.ds.window[(s) + (MIN_MATCH-1)]), \
    state.ds.prev[(s) & WMASK] = match_head = state.ds.head[state.ds.ins_h], \
    state.ds.head[state.ds.ins_h] = (s))

/* ===========================================================================
* Initialize the "longest match" routines for a new file
*
* IN assertion: window_size is > 0 if the input file is already read or
*    mmap'ed in the window[] array, 0 otherwise. In the first case,
*    window_size is sufficient to contain the whole input file plus
*    MIN_LOOKAHEAD bytes (to avoid referencing memory beyond the end
*    of window[] when looking for matches towards the end).
*/
void lm_init(TState &state, int pack_level, ush *flags)
{
	register unsigned j;

	Assert(state, pack_level >= 1 && pack_level <= 8, "bad pack level");

	/* Do not slide the window if the whole input is already in memory
	* (window_size > 0)
	*/
	state.ds.sliding = 0;
	if (state.ds.window_size == 0L) {
		state.ds.sliding = 1;
		state.ds.window_size = (ulg)2L * WSIZE;
	}

	/* Initialize the hash table (avoiding 64K overflow for 16 bit systems).
	* prev[] will be initialized on the fly.
	*/
	state.ds.head[HASH_SIZE - 1] = NIL;
	memset((char*)state.ds.head, NIL, (unsigned)(HASH_SIZE - 1)*sizeof(*state.ds.head));

	/* Set the default configuration parameters:
	*/
	state.ds.max_lazy_match = configuration_table[pack_level].max_lazy;
	state.ds.good_match = configuration_table[pack_level].good_length;
	state.ds.nice_match = configuration_table[pack_level].nice_length;
	state.ds.max_chain_length = configuration_table[pack_level].max_chain;
	if (pack_level <= 2) {
		*flags |= FAST;
	}
	else if (pack_level >= 8) {
		*flags |= SLOW;
	}
	/* ??? reduce max_chain_length for binary files */

	state.ds.strstart = 0;
	state.ds.block_start = 0L;

	j = WSIZE;
	j <<= 1; // Can read 64K in one step
	state.ds.lookahead = state.readfunc(state, (char*)state.ds.window, j);

	if (state.ds.lookahead == 0 || state.ds.lookahead == (unsigned)EOF) {
		state.ds.eofile = 1, state.ds.lookahead = 0;
		return;
	}
	state.ds.eofile = 0;
	/* Make sure that we always have enough lookahead. This is important
	* if input comes from a device such as a tty.
	*/
	if (state.ds.lookahead < MIN_LOOKAHEAD) fill_window(state);

	state.ds.ins_h = 0;
	for (j = 0; j<MIN_MATCH - 1; j++) UPDATE_HASH(state.ds.ins_h, state.ds.window[j]);
	/* If lookahead < MIN_MATCH, ins_h is garbage, but this is
	* not important since only literal bytes will be emitted.
	*/
}


/* ===========================================================================
* 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
*/
// For 80x86 and 680x0 and ARM, an optimized version is in match.asm or
// match.S. The code is functionally equivalent, so you can use the C version
// if desired. Which I do so desire!
int longest_match(TState &state, IPos cur_match)
{
	unsigned chain_length = state.ds.max_chain_length;   /* max hash chain length */
	register uch far *scan = state.ds.window + state.ds.strstart; /* current string */
	register uch far *match;                    /* matched string */
	register int len;                           /* length of current match */
	int best_len = state.ds.prev_length;                 /* best match length so far */
	IPos limit = state.ds.strstart > (IPos)MAX_DIST ? state.ds.strstart - (IPos)MAX_DIST : NIL;
	/* Stop when cur_match becomes <= limit. To simplify the code,
	* we prevent matches with the string of window index 0.
	*/

	// 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(state, HASH_BITS >= 8 && MAX_MATCH == 258, "Code too clever");



	register uch far *strend = state.ds.window + state.ds.strstart + MAX_MATCH;
	register uch scan_end1 = scan[best_len - 1];
	register uch scan_end = scan[best_len];

	/* Do not waste too much time if we already have a good match: */
	if (state.ds.prev_length >= state.ds.good_match) {
		chain_length >>= 2;
	}

	Assert(state, state.ds.strstart <= state.ds.window_size - MIN_LOOKAHEAD, "insufficient lookahead");

	do {
		Assert(state, cur_match < state.ds.strstart, "no future");
		match = state.ds.window + cur_match;

		/* Skip to next match if the match length cannot increase
		* or if the match length is less than 2:
		*/
		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++;

		/* 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(state, scan <= state.ds.window + (unsigned)(state.ds.window_size - 1), "wild scan");

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


		if (len > best_len) {
			state.ds.match_start = cur_match;
			best_len = len;
			if (len >= state.ds.nice_match) break;
			scan_end1 = scan[best_len - 1];
			scan_end = scan[best_len];
		}
	} while ((cur_match = state.ds.prev[cur_match & WMASK]) > limit
		&& --chain_length != 0);

	return best_len;
}



#define check_match(state,start, match, length)
// or alternatively...
//void check_match(TState &state,IPos start, IPos match, int length)
//{ // check that the match is indeed a match
//    if (memcmp((char*)state.ds.window + match,
//                (char*)state.ds.window + start, length) != EQUAL) {
//        fprintf(stderr,
//            " start %d, match %d, length %d\n",
//            start, match, length);
//        error("invalid match");
//    }
//    if (state.verbose > 1) {
//        fprintf(stderr,"\\[%d,%d]", start-match, length);
//        do { fprintf(stdout,"%c",state.ds.window[start++]); } while (--length != 0);
//    }
//}

/* ===========================================================================
* Fill the window when the lookahead becomes insufficient.
* Updates strstart and lookahead, and sets eofile if end of input file.
*
* IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0
* OUT assertions: strstart <= window_size-MIN_LOOKAHEAD
*    At least one byte has been read, or eofile is set; file reads are
*    performed for at least two bytes (required for the translate_eol option).
*/
void fill_window(TState &state)
{
	register unsigned n, m;
	unsigned more;    /* Amount of free space at the end of the window. */

	do {
		more = (unsigned)(state.ds.window_size - (ulg)state.ds.lookahead - (ulg)state.ds.strstart);

		/* 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 (more == (unsigned)EOF) {
			/* Very unlikely, but possible on 16 bit machine if strstart == 0
			* and lookahead == 1 (input done one byte at time)
			*/
			more--;

			/* For MMAP or BIG_MEM, the whole input file is already in memory so
			* we must not perform sliding. We must however call (*read_buf)() in
			* order to compute the crc, update lookahead and possibly set eofile.
			*/
		}
		else if (state.ds.strstart >= WSIZE + MAX_DIST && state.ds.sliding) {

			/* By the IN assertion, the window is not empty so we can't confuse
			* more == 0 with more == 64K on a 16 bit machine.
			*/
			memcpy((char*)state.ds.window, (char*)state.ds.window + WSIZE, (unsigned)WSIZE);
			state.ds.match_start -= WSIZE;
			state.ds.strstart -= WSIZE; /* we now have strstart >= MAX_DIST: */

			state.ds.block_start -= (long)WSIZE;

			for (n = 0; n < HASH_SIZE; n++) {
				m = state.ds.head[n];
				state.ds.head[n] = (Pos)(m >= WSIZE ? m - WSIZE : NIL);
			}
			for (n = 0; n < WSIZE; n++) {
				m = state.ds.prev[n];
				state.ds.prev[n] = (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.
				*/
			}
			more += WSIZE;
		}
		if (state.ds.eofile) 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 MMAP or BIG_MEM case (not yet supported in gzip),
		*   window_size == input_size + MIN_LOOKAHEAD  &&
		*   strstart + 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(state, more >= 2, "more < 2");

		n = state.readfunc(state, (char*)state.ds.window + state.ds.strstart + state.ds.lookahead, more);

		if (n == 0 || n == (unsigned)EOF) {
			state.ds.eofile = 1;
		}
		else {
			state.ds.lookahead += n;
		}
	} while (state.ds.lookahead < MIN_LOOKAHEAD && !state.ds.eofile);
}

/* ===========================================================================
* 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(state,eof) \
   flush_block(state,state.ds.block_start >= 0L ? (char*)&state.ds.window[(unsigned)state.ds.block_start] : \
                (char*)NULL, (long)state.ds.strstart - state.ds.block_start, (eof))

/* ===========================================================================
* Processes a new input file and return its compressed length. 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.
*/
ulg deflate_fast(TState &state)
{
	IPos hash_head = NIL;       /* head of the hash chain */
	int flush;                  /* set if current block must be flushed */
	unsigned match_length = 0;  /* length of best match */

	state.ds.prev_length = MIN_MATCH - 1;
	while (state.ds.lookahead != 0) {
		/* Insert the string window[strstart .. strstart+2] in the
		* dictionary, and set hash_head to the head of the hash chain:
		*/
		if (state.ds.lookahead >= MIN_MATCH)
			INSERT_STRING(state.ds.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 && state.ds.strstart - hash_head <= MAX_DIST) {
			/* 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).
			*/
			/* Do not look for matches beyond the end of the input.
			* This is necessary to make deflate deterministic.
			*/
			if ((unsigned)state.ds.nice_match > state.ds.lookahead) state.ds.nice_match = (int)state.ds.lookahead;
			match_length = longest_match(state, hash_head);
			/* longest_match() sets match_start */
			if (match_length > state.ds.lookahead) match_length = state.ds.lookahead;
		}
		if (match_length >= MIN_MATCH) {
			check_match(state, state.ds.strstart, state.ds.match_start, match_length);

			flush = ct_tally(state, state.ds.strstart - state.ds.match_start, match_length - MIN_MATCH);

			state.ds.lookahead -= match_length;

			/* Insert new strings in the hash table only if the match length
			* is not too large. This saves time but degrades compression.
			*/
			if (match_length <= state.ds.max_insert_length
				&& state.ds.lookahead >= MIN_MATCH) {
				match_length--; /* string at strstart already in hash table */
				do {
					state.ds.strstart++;
					INSERT_STRING(state.ds.strstart, hash_head);
					/* strstart never exceeds WSIZE-MAX_MATCH, so there are
					* always MIN_MATCH bytes ahead.
					*/
				} while (--match_length != 0);
				state.ds.strstart++;
			}
			else {
				state.ds.strstart += match_length;
				match_length = 0;
				state.ds.ins_h = state.ds.window[state.ds.strstart];
				UPDATE_HASH(state.ds.ins_h, state.ds.window[state.ds.strstart + 1]);
				Assert(state, MIN_MATCH == 3, "Call UPDATE_HASH() MIN_MATCH-3 more times");
			}
		}
		else {
			/* No match, output a literal byte */
			flush = ct_tally(state, 0, state.ds.window[state.ds.strstart]);
			state.ds.lookahead--;
			state.ds.strstart++;
		}
		if (flush) FLUSH_BLOCK(state, 0), state.ds.block_start = state.ds.strstart;

		/* 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 (state.ds.lookahead < MIN_LOOKAHEAD) fill_window(state);
	}
	return FLUSH_BLOCK(state, 1); /* eof */
}

/* ===========================================================================
* 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.
*/
ulg deflate(TState &state)
{
	IPos hash_head = NIL;       /* head of hash chain */
	IPos prev_match;            /* previous match */
	int flush;                  /* set if current block must be flushed */
	int match_available = 0;    /* set if previous match exists */
	register unsigned match_length = MIN_MATCH - 1; /* length of best match */

	if (state.level <= 3) return deflate_fast(state); /* optimized for speed */

	/* Process the input block. */
	while (state.ds.lookahead != 0) {
		/* Insert the string window[strstart .. strstart+2] in the
		* dictionary, and set hash_head to the head of the hash chain:
		*/
		if (state.ds.lookahead >= MIN_MATCH)
			INSERT_STRING(state.ds.strstart, hash_head);

		/* Find the longest match, discarding those <= prev_length.
		*/
		state.ds.prev_length = match_length, prev_match = state.ds.match_start;
		match_length = MIN_MATCH - 1;

		if (hash_head != NIL && state.ds.prev_length < state.ds.max_lazy_match &&
			state.ds.strstart - hash_head <= MAX_DIST) {
			/* 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).
			*/
			/* Do not look for matches beyond the end of the input.
			* This is necessary to make deflate deterministic.
			*/
			if ((unsigned)state.ds.nice_match > state.ds.lookahead) state.ds.nice_match = (int)state.ds.lookahead;
			match_length = longest_match(state, hash_head);
			/* longest_match() sets match_start */
			if (match_length > state.ds.lookahead) match_length = state.ds.lookahead;

			/* Ignore a length 3 match if it is too distant: */
			if (match_length == MIN_MATCH && state.ds.strstart - state.ds.match_start > TOO_FAR){
				/* If prev_match is also MIN_MATCH, match_start is garbage
				* but we will ignore the current match anyway.
				*/
				match_length = MIN_MATCH - 1;
			}
		}
		/* If there was a match at the previous step and the current
		* match is not better, output the previous match:
		*/
		if (state.ds.prev_length >= MIN_MATCH && match_length <= state.ds.prev_length) {
			unsigned max_insert = state.ds.strstart + state.ds.lookahead - MIN_MATCH;
			check_match(state, state.ds.strstart - 1, prev_match, state.ds.prev_length);
			flush = ct_tally(state, state.ds.strstart - 1 - prev_match, state.ds.prev_length - MIN_MATCH);

			/* Insert in hash table all strings up to the end of the match.
			* strstart-1 and strstart are already inserted.
			*/
			state.ds.lookahead -= state.ds.prev_length - 1;
			state.ds.prev_length -= 2;
			do {
				if (++state.ds.strstart <= max_insert) {
					INSERT_STRING(state.ds.strstart, hash_head);
					/* strstart never exceeds WSIZE-MAX_MATCH, so there are
					* always MIN_MATCH bytes ahead.
					*/
				}
			} while (--state.ds.prev_length != 0);
			state.ds.strstart++;
			match_available = 0;
			match_length = MIN_MATCH - 1;

			if (flush) FLUSH_BLOCK(state, 0), state.ds.block_start = state.ds.strstart;

		}
		else if (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.
			*/
			if (ct_tally(state, 0, state.ds.window[state.ds.strstart - 1])) {
				FLUSH_BLOCK(state, 0), state.ds.block_start = state.ds.strstart;
			}
			state.ds.strstart++;
			state.ds.lookahead--;
		}
		else {
			/* There is no previous match to compare with, wait for
			* the next step to decide.
			*/
			match_available = 1;
			state.ds.strstart++;
			state.ds.lookahead--;
		}
		//        Assert(state,strstart <= isize && lookahead <= isize, "a bit too far");

		/* 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 (state.ds.lookahead < MIN_LOOKAHEAD) fill_window(state);
	}
	if (match_available) ct_tally(state, 0, state.ds.window[state.ds.strstart - 1]);

	return FLUSH_BLOCK(state, 1); /* eof */
}












int putlocal(struct zlist far *z, WRITEFUNC wfunc, void *param)
{ // Write a local header described by *z to file *f.  Return a ZE_ error code.
	PUTLG(LOCSIG, f);
	PUTSH(z->ver, f);
	PUTSH(z->lflg, f);
	PUTSH(z->how, f);
	PUTLG(z->tim, f);
	PUTLG(z->crc, f);
	PUTLG(z->siz, f);
	PUTLG(z->len, f);
	PUTSH(z->nam, f);
	PUTSH(z->ext, f);
	size_t res = (size_t)wfunc(param, z->iname, (unsigned int)z->nam);
	if (res != z->nam) return ZE_TEMP;
	if (z->ext)
	{
		res = (size_t)wfunc(param, z->extra, (unsigned int)z->ext);
		if (res != z->ext) return ZE_TEMP;
	}
	return ZE_OK;
}

int putextended(struct zlist far *z, WRITEFUNC wfunc, void *param)
{ // Write an extended local header described by *z to file *f. Returns a ZE_ code
	PUTLG(EXTLOCSIG, f);
	PUTLG(z->crc, f);
	PUTLG(z->siz, f);
	PUTLG(z->len, f);
	return ZE_OK;
}

int putcentral(struct zlist far *z, WRITEFUNC wfunc, void *param)
{ // Write a central header entry of *z to file *f. Returns a ZE_ code.
	PUTLG(CENSIG, f);
	PUTSH(z->vem, f);
	PUTSH(z->ver, f);
	PUTSH(z->flg, f);
	PUTSH(z->how, f);
	PUTLG(z->tim, f);
	PUTLG(z->crc, f);
	PUTLG(z->siz, f);
	PUTLG(z->len, f);
	PUTSH(z->nam, f);
	PUTSH(z->cext, f);
	PUTSH(z->com, f);
	PUTSH(z->dsk, f);
	PUTSH(z->att, f);
	PUTLG(z->atx, f);
	PUTLG(z->off, f);
	if ((size_t)wfunc(param, z->iname, (unsigned int)z->nam) != z->nam ||
		(z->cext && (size_t)wfunc(param, z->cextra, (unsigned int)z->cext) != z->cext) ||
		(z->com && (size_t)wfunc(param, z->comment, (unsigned int)z->com) != z->com))
		return ZE_TEMP;
	return ZE_OK;
}


int putend(int n, ulg s, ulg c, extent m, char *z, WRITEFUNC wfunc, void *param)
{ // write the end of the central-directory-data to file *f.
	PUTLG(ENDSIG, f);
	PUTSH(0, f);
	PUTSH(0, f);
	PUTSH(n, f);
	PUTSH(n, f);
	PUTLG(s, f);
	PUTLG(c, f);
	PUTSH(m, f);
	// Write the comment, if any
	if (m && wfunc(param, z, (unsigned int)m) != m) return ZE_TEMP;
	return ZE_OK;
}






const ulg crc_table[256] = {
	0x00000000L, 0x77073096L, 0xee0e612cL, 0x990951baL, 0x076dc419L,
	0x706af48fL, 0xe963a535L, 0x9e6495a3L, 0x0edb8832L, 0x79dcb8a4L,
	0xe0d5e91eL, 0x97d2d988L, 0x09b64c2bL, 0x7eb17cbdL, 0xe7b82d07L,
	0x90bf1d91L, 0x1db71064L, 0x6ab020f2L, 0xf3b97148L, 0x84be41deL,
	0x1adad47dL, 0x6ddde4ebL, 0xf4d4b551L, 0x83d385c7L, 0x136c9856L,
	0x646ba8c0L, 0xfd62f97aL, 0x8a65c9ecL, 0x14015c4fL, 0x63066cd9L,
	0xfa0f3d63L, 0x8d080df5L, 0x3b6e20c8L, 0x4c69105eL, 0xd56041e4L,
	0xa2677172L, 0x3c03e4d1L, 0x4b04d447L, 0xd20d85fdL, 0xa50ab56bL,
	0x35b5a8faL, 0x42b2986cL, 0xdbbbc9d6L, 0xacbcf940L, 0x32d86ce3L,
	0x45df5c75L, 0xdcd60dcfL, 0xabd13d59L, 0x26d930acL, 0x51de003aL,
	0xc8d75180L, 0xbfd06116L, 0x21b4f4b5L, 0x56b3c423L, 0xcfba9599L,
	0xb8bda50fL, 0x2802b89eL, 0x5f058808L, 0xc60cd9b2L, 0xb10be924L,
	0x2f6f7c87L, 0x58684c11L, 0xc1611dabL, 0xb6662d3dL, 0x76dc4190L,
	0x01db7106L, 0x98d220bcL, 0xefd5102aL, 0x71b18589L, 0x06b6b51fL,
	0x9fbfe4a5L, 0xe8b8d433L, 0x7807c9a2L, 0x0f00f934L, 0x9609a88eL,
	0xe10e9818L, 0x7f6a0dbbL, 0x086d3d2dL, 0x91646c97L, 0xe6635c01L,
	0x6b6b51f4L, 0x1c6c6162L, 0x856530d8L, 0xf262004eL, 0x6c0695edL,
	0x1b01a57bL, 0x8208f4c1L, 0xf50fc457L, 0x65b0d9c6L, 0x12b7e950L,
	0x8bbeb8eaL, 0xfcb9887cL, 0x62dd1ddfL, 0x15da2d49L, 0x8cd37cf3L,
	0xfbd44c65L, 0x4db26158L, 0x3ab551ceL, 0xa3bc0074L, 0xd4bb30e2L,
	0x4adfa541L, 0x3dd895d7L, 0xa4d1c46dL, 0xd3d6f4fbL, 0x4369e96aL,
	0x346ed9fcL, 0xad678846L, 0xda60b8d0L, 0x44042d73L, 0x33031de5L,
	0xaa0a4c5fL, 0xdd0d7cc9L, 0x5005713cL, 0x270241aaL, 0xbe0b1010L,
	0xc90c2086L, 0x5768b525L, 0x206f85b3L, 0xb966d409L, 0xce61e49fL,
	0x5edef90eL, 0x29d9c998L, 0xb0d09822L, 0xc7d7a8b4L, 0x59b33d17L,
	0x2eb40d81L, 0xb7bd5c3bL, 0xc0ba6cadL, 0xedb88320L, 0x9abfb3b6L,
	0x03b6e20cL, 0x74b1d29aL, 0xead54739L, 0x9dd277afL, 0x04db2615L,
	0x73dc1683L, 0xe3630b12L, 0x94643b84L, 0x0d6d6a3eL, 0x7a6a5aa8L,
	0xe40ecf0bL, 0x9309ff9dL, 0x0a00ae27L, 0x7d079eb1L, 0xf00f9344L,
	0x8708a3d2L, 0x1e01f268L, 0x6906c2feL, 0xf762575dL, 0x806567cbL,
	0x196c3671L, 0x6e6b06e7L, 0xfed41b76L, 0x89d32be0L, 0x10da7a5aL,
	0x67dd4accL, 0xf9b9df6fL, 0x8ebeeff9L, 0x17b7be43L, 0x60b08ed5L,
	0xd6d6a3e8L, 0xa1d1937eL, 0x38d8c2c4L, 0x4fdff252L, 0xd1bb67f1L,
	0xa6bc5767L, 0x3fb506ddL, 0x48b2364bL, 0xd80d2bdaL, 0xaf0a1b4cL,
	0x36034af6L, 0x41047a60L, 0xdf60efc3L, 0xa867df55L, 0x316e8eefL,
	0x4669be79L, 0xcb61b38cL, 0xbc66831aL, 0x256fd2a0L, 0x5268e236L,
	0xcc0c7795L, 0xbb0b4703L, 0x220216b9L, 0x5505262fL, 0xc5ba3bbeL,
	0xb2bd0b28L, 0x2bb45a92L, 0x5cb36a04L, 0xc2d7ffa7L, 0xb5d0cf31L,
	0x2cd99e8bL, 0x5bdeae1dL, 0x9b64c2b0L, 0xec63f226L, 0x756aa39cL,
	0x026d930aL, 0x9c0906a9L, 0xeb0e363fL, 0x72076785L, 0x05005713L,
	0x95bf4a82L, 0xe2b87a14L, 0x7bb12baeL, 0x0cb61b38L, 0x92d28e9bL,
	0xe5d5be0dL, 0x7cdcefb7L, 0x0bdbdf21L, 0x86d3d2d4L, 0xf1d4e242L,
	0x68ddb3f8L, 0x1fda836eL, 0x81be16cdL, 0xf6b9265bL, 0x6fb077e1L,
	0x18b74777L, 0x88085ae6L, 0xff0f6a70L, 0x66063bcaL, 0x11010b5cL,
	0x8f659effL, 0xf862ae69L, 0x616bffd3L, 0x166ccf45L, 0xa00ae278L,
	0xd70dd2eeL, 0x4e048354L, 0x3903b3c2L, 0xa7672661L, 0xd06016f7L,
	0x4969474dL, 0x3e6e77dbL, 0xaed16a4aL, 0xd9d65adcL, 0x40df0b66L,
	0x37d83bf0L, 0xa9bcae53L, 0xdebb9ec5L, 0x47b2cf7fL, 0x30b5ffe9L,
	0xbdbdf21cL, 0xcabac28aL, 0x53b39330L, 0x24b4a3a6L, 0xbad03605L,
	0xcdd70693L, 0x54de5729L, 0x23d967bfL, 0xb3667a2eL, 0xc4614ab8L,
	0x5d681b02L, 0x2a6f2b94L, 0xb40bbe37L, 0xc30c8ea1L, 0x5a05df1bL,
	0x2d02ef8dL
};

#define CRC32(c, b) (crc_table[((int)(c) ^ (b)) & 0xff] ^ ((c) >> 8))
#define DO1(buf)  crc = CRC32(crc, *buf++)
#define DO2(buf)  DO1(buf); DO1(buf)
#define DO4(buf)  DO2(buf); DO2(buf)
#define DO8(buf)  DO4(buf); DO4(buf)

ulg crc32(ulg crc, const uch *buf, extent len)
{
	if (buf == NULL) return 0L;
	crc = crc ^ 0xffffffffL;
	while (len >= 8) { DO8(buf); len -= 8; }
	if (len) do { DO1(buf); } while (--len);
	return crc ^ 0xffffffffL;  // (instead of ~c for 64-bit machines)
}








bool HasZipSuffix(const char *fn)
{
	const char *ext = fn + strlen(fn);
	while (ext>fn && *ext != '.') ext--;
	if (ext == fn && *ext != '.') return false;
	if (stricmp(ext, ".Z") == 0) return true;
	if (stricmp(ext, ".zip") == 0) return true;
	if (stricmp(ext, ".zoo") == 0) return true;
	if (stricmp(ext, ".arc") == 0) return true;
	if (stricmp(ext, ".lzh") == 0) return true;
	if (stricmp(ext, ".arj") == 0) return true;
	if (stricmp(ext, ".gz") == 0) return true;
	if (stricmp(ext, ".tgz") == 0) return true;
	return false;
}


time_t filetime2timet(const FILETIME ft)
{
	SYSTEMTIME st; FileTimeToSystemTime(&ft, &st);
	if (st.wYear<1970) { st.wYear = 1970; st.wMonth = 1; st.wDay = 1; }
	if (st.wYear >= 2038) { st.wYear = 2037; st.wMonth = 12; st.wDay = 31; }
	struct tm tm;
	tm.tm_sec = st.wSecond;
	tm.tm_min = st.wMinute;
	tm.tm_hour = st.wHour;
	tm.tm_mday = st.wDay;
	tm.tm_mon = st.wMonth - 1;
	tm.tm_year = st.wYear - 1900;
	tm.tm_isdst = 0;
	time_t t = mktime(&tm);
	return t;
}


ZRESULT GetFileInfo(HANDLE hf, ulg *attr, long *size, iztimes *times, ulg *timestamp)
{
	DWORD type = GetFileType(hf);
	if (type != FILE_TYPE_DISK)
		return ZR_NOTINITED;
	// The handle must be a handle to a file
	// The date and time is returned in a long with the date most significant to allow
	// unsigned integer comparison of absolute times. The attributes have two
	// high bytes unix attr, and two low bytes a mapping of that to DOS attr.
	//struct stat s; int res=stat(fn,&s); if (res!=0) return false;
	// translate windows file attributes into zip ones.
	BY_HANDLE_FILE_INFORMATION bhi;
	BOOL res = GetFileInformationByHandle(hf, &bhi);
	if (!res)
		return ZR_NOFILE;

	// +++1.3
	/// Convert times from UTC to local time. MSDN says that FILETIME is local
	/// for FAT file system and UTC for NTFS system, but tests show that both FAT and NTFS
	/// return UTC time.
	{
		// Get time zone difference
		SYSTEMTIME stUTC, stLocal;
		GetSystemTime(&stUTC);
		GetLocalTime(&stLocal); // could be a few milliseconds difference, but should we care?
		FILETIME ftUTC, ftLocal;
		SystemTimeToFileTime(&stUTC, &ftUTC);
		SystemTimeToFileTime(&stLocal, &ftLocal);
		LONG64 uiUTC, uiLocal;
		memcpy(&uiUTC, &ftUTC, min(sizeof(LONG64), sizeof(FILETIME))); // use 'min' as safeguard, however both sizes should be the same: 64-bit
		memcpy(&uiLocal, &ftLocal, min(sizeof(LONG64), sizeof(FILETIME)));
		LONG64 uiTimeDiff = uiUTC - uiLocal;

		// apply difference
		FILETIME* pFileTimes[3] = { &bhi.ftLastWriteTime, &bhi.ftLastAccessTime, &bhi.ftCreationTime };
		for (int i = 0; i<3; i++){
			LONG64 uiUTC_file;
			memcpy(&uiUTC_file, pFileTimes[i], min(sizeof(LONG64), sizeof(FILETIME)));
			LONG64 uiLocal_file = uiUTC_file - uiTimeDiff;
			memcpy(pFileTimes[i], &uiLocal_file, min(sizeof(LONG64), sizeof(FILETIME)));
		}
	}

	DWORD fa = bhi.dwFileAttributes;
	ulg a = 0;
	// Zip uses the lower word for its interpretation of windows stuff
	if (fa&FILE_ATTRIBUTE_READONLY) a |= 0x01;
	if (fa&FILE_ATTRIBUTE_HIDDEN)   a |= 0x02;
	if (fa&FILE_ATTRIBUTE_SYSTEM)   a |= 0x04;
	if (fa&FILE_ATTRIBUTE_DIRECTORY)a |= 0x10;
	if (fa&FILE_ATTRIBUTE_ARCHIVE)  a |= 0x20;
	// It uses the upper word for standard unix attr, which we must manually construct
	if (fa&FILE_ATTRIBUTE_DIRECTORY)a |= 0x40000000;  // directory
	else a |= 0x80000000;  // normal file
	a |= 0x01000000;      // readable
	if (fa&FILE_ATTRIBUTE_READONLY) {}
	else a |= 0x00800000; // writeable
	// now just a small heuristic to check if it's an executable:
	DWORD red, hsize = GetFileSize(hf, NULL); if (hsize>40)
	{
		SetFilePointer(hf, 0, NULL, FILE_BEGIN); unsigned short magic; ReadFile(hf, &magic, sizeof(magic), &red, NULL);
		SetFilePointer(hf, 36, NULL, FILE_BEGIN); unsigned long hpos;  ReadFile(hf, &hpos, sizeof(hpos), &red, NULL);
		if (magic == 0x54AD && hsize>hpos + 4 + 20 + 28)
		{
			SetFilePointer(hf, hpos, NULL, FILE_BEGIN); unsigned long signature; ReadFile(hf, &signature, sizeof(signature), &red, NULL);
			if (signature == IMAGE_DOS_SIGNATURE || signature == IMAGE_OS2_SIGNATURE
				|| signature == IMAGE_OS2_SIGNATURE_LE || signature == IMAGE_NT_SIGNATURE)
			{
				a |= 0x00400000; // executable
			}
		}
	}
	//
	if (attr != NULL) *attr = a;
	if (size != NULL) *size = hsize;
	if (times != NULL)
	{ // time_t is 32bit number of seconds elapsed since 0:0:0GMT, Jan1, 1970.
		// but FILETIME is 64bit number of 100-nanosecs since Jan1, 1601
		times->atime = filetime2timet(bhi.ftLastAccessTime);
		times->mtime = filetime2timet(bhi.ftLastWriteTime);
		times->ctime = filetime2timet(bhi.ftCreationTime);
	}
	if (timestamp != NULL)
	{
		WORD dosdate, dostime;
		FileTimeToDosDateTime(&bhi.ftLastWriteTime, &dosdate, &dostime);
		*timestamp = (WORD)dostime | (((DWORD)dosdate) << 16);
	}
	return ZR_OK;
}





///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////

class TZip
{
public:
	TZip() : hfout(0), hmapout(0), zfis(0), obuf(0), hfin(0), writ(0), oerr(false), hasputcen(false), ooffset(0) {}
	~TZip() {}

	// These variables say about the file we're writing into
	// We can write to pipe, file-by-handle, file-by-name, memory-to-memmapfile
	HANDLE hfout;             // if valid, we'll write here (for files or pipes)
	HANDLE hmapout;           // otherwise, we'll write here (for memmap)
	unsigned ooffset;         // for hfout, this is where the pointer was initially
	ZRESULT oerr;             // did a write operation give rise to an error?
	unsigned writ;            // how far have we written. This is maintained by Add, not write(), to avoid confusion over seeks
	bool ocanseek;            // can we seek?
	char *obuf;               // this is where we've locked mmap to view.
	unsigned int opos;        // current pos in the mmap
	unsigned int mapsize;     // the size of the map we created
	bool hasputcen;           // have we yet placed the central directory?
	//
	TZipFileInfo *zfis;       // each file gets added onto this list, for writing the table at the end

	ZRESULT Create(void *z, unsigned int len, DWORD flags);
	static unsigned sflush(void *param, const char *buf, unsigned *size);
	static unsigned swrite(void *param, const char *buf, unsigned size);
	unsigned int write(const char *buf, unsigned int size);
	bool oseek(unsigned int pos);
	ZRESULT GetMemory(void **pbuf, unsigned long *plen);
	ZRESULT Close();

	// some variables to do with the file currently being read:
	// I haven't done it object-orientedly here, just put them all
	// together, since OO didn't seem to make the design any clearer.
	ulg attr; iztimes times; ulg timestamp;  // all open_* methods set these
	bool iseekable; long isize, ired;         // size is not set until close() on pips
	ulg crc;                                 // crc is not set until close(). iwrit is cumulative
	HANDLE hfin; bool selfclosehf;           // for input files and pipes
	const char *bufin; unsigned int lenin, posin; // for memory
	// and a variable for what we've done with the input: (i.e. compressed it!)
	ulg csize;                               // compressed size, set by the compression routines
	// and this is used by some of the compression routines
	char buf[16384];


	ZRESULT open_file(const TCHAR *fn);
	ZRESULT open_handle(HANDLE hf, unsigned int len);
	ZRESULT open_mem(void *src, unsigned int len);
	ZRESULT open_dir();
	static unsigned sread(TState &s, char *buf, unsigned size);
	unsigned read(char *buf, unsigned size);
	ZRESULT iclose();

	ZRESULT ideflate(TZipFileInfo *zfi);
	ZRESULT istore();

	ZRESULT Add(const char *odstzn, void *src, unsigned int len, DWORD flags);
	ZRESULT AddCentral();

};

ZRESULT TZip::Create(void *z, unsigned int len, DWORD flags)
{
	if (hfout != 0 || hmapout != 0 || obuf != 0 || writ != 0 || oerr != ZR_OK || hasputcen)
		return ZR_NOTINITED;
	//
	if (flags == ZIP_HANDLE)
	{
		HANDLE hf = (HANDLE)z;
		BOOL res = DuplicateHandle(GetCurrentProcess(), hf, GetCurrentProcess(), &hfout, 0, FALSE, DUPLICATE_SAME_ACCESS);
		if (!res)
			return ZR_NODUPH;
		// now we have our own hfout, which we must close. And the caller will close hf
		DWORD type = GetFileType(hfout);
		ocanseek = (type == FILE_TYPE_DISK);
		if (type == FILE_TYPE_DISK)
			ooffset = SetFilePointer(hfout, 0, NULL, FILE_CURRENT);
		else
			ooffset = 0;
		return ZR_OK;
	}
	else if (flags == ZIP_FILENAME)
	{
#ifdef _UNICODE
		const TCHAR *fn = (const TCHAR*)z;
		hfout = CreateFileW(fn, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
#else
		const char *fn = (const char*)z;
		hfout = CreateFileA(fn, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
#endif

		if (hfout == INVALID_HANDLE_VALUE)
		{
			hfout = 0;
			return ZR_NOFILE;
		}
		ocanseek = true;
		ooffset = 0;
		return ZR_OK;
	}
	else if (flags == ZIP_MEMORY)
	{
		unsigned int size = len;
		if (size == 0)
			return ZR_MEMSIZE;
		if (z != 0)
			obuf = (char*)z;
		else
		{
			hmapout = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, size, NULL);
			if (hmapout == NULL)
				return ZR_NOALLOC;
			obuf = (char*)MapViewOfFile(hmapout, FILE_MAP_ALL_ACCESS, 0, 0, size);
			if (obuf == 0)
			{
				CloseHandle(hmapout);
				hmapout = 0;
				return ZR_NOALLOC;
			}
		}
		ocanseek = true;
		opos = 0;
		mapsize = size;
		return ZR_OK;
	}
	else
		return ZR_ARGS;
}


unsigned TZip::sflush(void *param, const char *buf, unsigned *size)
{ // static
	if (*size == 0) return 0;
	TZip *zip = (TZip*)param;
	unsigned int writ = zip->write(buf, *size);
	if (writ != 0) *size = 0;
	return writ;
}
unsigned TZip::swrite(void *param, const char *buf, unsigned size)
{ // static
	if (size == 0) return 0;
	TZip *zip = (TZip*)param; return zip->write(buf, size);
}

#if 0  // -----------------------------------------------------------
unsigned int TZip::write(const char *buf, unsigned int size)
{
	if (obuf != 0)
	{
		if (opos + size >= mapsize) { oerr = ZR_MEMSIZE; return 0; }
		memcpy(obuf + opos, buf, size);
		opos += size;
		return size;
	}
	else if (hfout != 0)
	{
		DWORD writ; WriteFile(hfout, buf, size, &writ, NULL);
		return writ;
	}
	oerr = ZR_NOTINITED; return 0;
}
#endif // -----------------------------------------------------------

//+++1.2
unsigned int TZip::write(const char *buf, unsigned int size)
{
	if (obuf != 0)
	{
		if (opos + size >= mapsize)
		{
			int newmapsize = 2 * mapsize>opos + size ? 2 * mapsize : opos + size;
			HANDLE hmapout2 = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, newmapsize, NULL);
			if (hmapout2 == NULL)
				return ZR_NOALLOC;
			char *obuf2 = NULL; // this is where we've locked mmap to view.

			obuf2 = (char*)MapViewOfFile(hmapout2, FILE_MAP_ALL_ACCESS, 0, 0, newmapsize);
			if (obuf2 == 0)
			{
				CloseHandle(hmapout2);
				hmapout2 = 0;
				return ZR_NOALLOC;
			}

			memcpy(obuf2, obuf, mapsize);

			UnmapViewOfFile(obuf);
			CloseHandle(hmapout);

			mapsize = newmapsize;
			obuf = obuf2;
			hmapout = hmapout2;
		}
		memcpy(obuf + opos, buf, size);
		opos += size;
		return size;
	}
	else if (hfout != 0)
	{
		DWORD writ = 0;
		WriteFile(hfout, buf, size, &writ, NULL);
		return writ;
	}
	oerr = ZR_NOTINITED;
	return 0;
}


bool TZip::oseek(unsigned int pos)
{
	if (!ocanseek) { oerr = ZR_SEEK; return false; }
	if (obuf != 0)
	{
		if (pos >= mapsize) { oerr = ZR_MEMSIZE; return false; }
		opos = pos;
		return true;
	}
	else if (hfout != 0)
	{
		SetFilePointer(hfout, pos + ooffset, NULL, FILE_BEGIN);
		return true;
	}
	oerr = ZR_NOTINITED; return 0;
}

ZRESULT TZip::GetMemory(void **pbuf, unsigned long *plen)
{ // When the user calls GetMemory, they're presumably at the end
	// of all their adding. In any case, we have to add the central
	// directory now, otherwise the memory we tell them won't be complete.
	if (!hasputcen) AddCentral(); hasputcen = true;
	if (pbuf != NULL) *pbuf = (void*)obuf;
	if (plen != NULL) *plen = writ;
	if (obuf == NULL) return ZR_NOTMMAP;
	return ZR_OK;
}

ZRESULT TZip::Close()
{ // if the directory hadn't already been added through a call to GetMemory,
	// then we do it now
	ZRESULT res = ZR_OK; if (!hasputcen) res = AddCentral(); hasputcen = true;
	if (obuf != 0 && hmapout != 0) UnmapViewOfFile(obuf); obuf = 0;
	if (hmapout != 0) CloseHandle(hmapout); hmapout = 0;
	if (hfout != 0) CloseHandle(hfout); hfout = 0;
	return res;
}




ZRESULT TZip::open_file(const TCHAR *fn)
{
	hfin = 0; bufin = 0; selfclosehf = false; crc = CRCVAL_INITIAL; isize = 0; csize = 0; ired = 0;
	if (fn == 0) return ZR_ARGS;
	HANDLE hf = CreateFile(fn, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, 0, NULL);
	if (hf == INVALID_HANDLE_VALUE) return ZR_NOFILE;
	ZRESULT res = open_handle(hf, 0);
	if (res != ZR_OK) { CloseHandle(hf); return res; }
	selfclosehf = true;
	return ZR_OK;
}
ZRESULT TZip::open_handle(HANDLE hf, unsigned int len)
{
	hfin = 0; bufin = 0; selfclosehf = false; crc = CRCVAL_INITIAL; isize = 0; csize = 0; ired = 0;
	if (hf == 0 || hf == INVALID_HANDLE_VALUE) return ZR_ARGS;
	DWORD type = GetFileType(hf);
	if (type == FILE_TYPE_DISK)
	{
		ZRESULT res = GetFileInfo(hf, &attr, &isize, &times, &timestamp);
		if (res != ZR_OK) return res;
		SetFilePointer(hf, 0, NULL, FILE_BEGIN); // because GetFileInfo will have screwed it up
		iseekable = true; hfin = hf;
		return ZR_OK;
	}
	else
	{
		attr = 0x80000000;      // just a normal file
		isize = -1;            // can't know size until at the end
		if (len != 0) isize = len; // unless we were told explicitly!
		iseekable = false;
		SYSTEMTIME st; GetLocalTime(&st);
		FILETIME ft;   SystemTimeToFileTime(&st, &ft);
		WORD dosdate, dostime; FileTimeToDosDateTime(&ft, &dosdate, &dostime);
		times.atime = filetime2timet(ft);
		times.mtime = times.atime;
		times.ctime = times.atime;
		timestamp = (WORD)dostime | (((DWORD)dosdate) << 16);
		hfin = hf;
		return ZR_OK;
	}
}
ZRESULT TZip::open_mem(void *src, unsigned int len)
{
	hfin = 0; bufin = (const char*)src; selfclosehf = false; crc = CRCVAL_INITIAL; ired = 0; csize = 0; ired = 0;
	lenin = len; posin = 0;
	if (src == 0 || len == 0) return ZR_ARGS;
	attr = 0x80000000; // just a normal file
	isize = len;
	iseekable = true;
	SYSTEMTIME st; GetLocalTime(&st);
	FILETIME ft;   SystemTimeToFileTime(&st, &ft);
	WORD dosdate, dostime; FileTimeToDosDateTime(&ft, &dosdate, &dostime);
	times.atime = filetime2timet(ft);
	times.mtime = times.atime;
	times.ctime = times.atime;
	timestamp = (WORD)dostime | (((DWORD)dosdate) << 16);
	return ZR_OK;
}
ZRESULT TZip::open_dir()
{
	hfin = 0; bufin = 0; selfclosehf = false; crc = CRCVAL_INITIAL; isize = 0; csize = 0; ired = 0;
	attr = 0x41C00010; // a readable writable directory, and again directory
	isize = 0;
	iseekable = false;
	SYSTEMTIME st; GetLocalTime(&st);
	FILETIME ft;   SystemTimeToFileTime(&st, &ft);
	WORD dosdate, dostime; FileTimeToDosDateTime(&ft, &dosdate, &dostime);
	times.atime = filetime2timet(ft);
	times.mtime = times.atime;
	times.ctime = times.atime;
	timestamp = (WORD)dostime | (((DWORD)dosdate) << 16);
	return ZR_OK;
}

unsigned TZip::sread(TState &s, char *buf, unsigned size)
{ // static
	TZip *zip = (TZip*)s.param;
	return zip->read(buf, size);
}

unsigned TZip::read(char *buf, unsigned size)
{
	if (bufin != 0)
	{
		if (posin >= lenin) return 0; // end of input
		ulg red = lenin - posin;
		if (red>size) red = size;
		memcpy(buf, bufin + posin, red);
		posin += red;
		ired += red;
		crc = crc32(crc, (uch*)buf, red);
		return red;
	}
	else if (hfin != 0)
	{
		DWORD red;
		BOOL ok = ReadFile(hfin, buf, size, &red, NULL);
		if (!ok) return 0;
		ired += red;
		crc = crc32(crc, (uch*)buf, red);
		return red;
	}
	else { oerr = ZR_NOTINITED; return 0; }
}

ZRESULT TZip::iclose()
{
	if (selfclosehf && hfin != 0) CloseHandle(hfin); hfin = 0;
	bool mismatch = (isize != -1 && isize != ired);
	isize = ired; // and crc has been being updated anyway
	if (mismatch) return ZR_MISSIZE;
	else return ZR_OK;
}



#if 0  // -----------------------------------------------------------
ZRESULT TZip::ideflate(TZipFileInfo *zfi)
{
	TState state;
	state.readfunc = sread; state.flush_outbuf = sflush;
	state.param = this; state.level = 8; state.seekable = iseekable; state.err = NULL;
	// the following line will make ct_init realise it has to perform the init
	state.ts.static_dtree[0].dl.len = 0;
	// It would be nicer if I could figure out precisely which data had to
	// be initted each time, and which didn't, but that's kind of difficult.
	// Maybe for the next version...
	//
	bi_init(state, buf, sizeof(buf), TRUE); // it used to be just 1024-size, not 16384 as here
	ct_init(state, &zfi->att);
	lm_init(state, state.level, &zfi->flg);
	ulg sz = deflate(state);
	csize = sz;
	if (state.err != NULL) return ZR_FLATE;
	else return ZR_OK;
}
#endif // -----------------------------------------------------------

//+++1.2
// create state object on heap
ZRESULT TZip::ideflate(TZipFileInfo *zfi)
{
	ZRESULT zr = ZR_OK;
	TState* state = new TState();
	(*state).readfunc = sread; (*state).flush_outbuf = sflush;
	(*state).param = this; (*state).level = 8; (*state).seekable = iseekable; (*state).err = NULL;
	// the following line will make ct_init realise it has to perform the init
	(*state).ts.static_dtree[0].dl.len = 0;
	// It would be nicer if I could figure out precisely which data had to
	// be initted each time, and which didn't, but that's kind of difficult.
	// Maybe for the next version...
	//
	bi_init(*state, buf, sizeof(buf), TRUE); // it used to be just 1024-size, not 16384 as here
	ct_init(*state, &zfi->att);
	lm_init(*state, (*state).level, &zfi->flg);
	ulg sz = deflate(*state);
	csize = sz;
	if ((*state).err != NULL)
	{
		zr = ZR_FLATE;
	}
	delete state;
	return zr;
}

ZRESULT TZip::istore()
{
	ulg size = 0;
	for (;;)
	{
		unsigned int cin = read(buf, 16384); if (cin <= 0 || cin == (unsigned int)EOF) break;
		unsigned int cout = write(buf, cin); if (cout != cin) return ZR_MISSIZE;
		size += cin;
	}
	csize = size;
	return ZR_OK;
}




ZRESULT TZip::Add(const char *odstzn, void *src, unsigned int len, DWORD flags)
{
	if (oerr)
		return ZR_FAILED;
	if (hasputcen)
		return ZR_ENDED;

	// zip has its own notion of what its names should look like: i.e. dir/file.stuff
	char dstzn[MAX_PATH];
	strcpy(dstzn, odstzn);
	if (*dstzn == 0)
		return ZR_ARGS;
	char *d = dstzn;
	while (*d != 0)
	{
		if (*d == '\\')
			*d = '/'; d++;
	}
	bool isdir = (flags == ZIP_FOLDER);
	bool needs_trailing_slash = (isdir && dstzn[strlen(dstzn) - 1] != '/');
	int method = DEFLATE;
	if (isdir || HasZipSuffix(dstzn))
		method = STORE;

	// now open whatever was our input source:
	ZRESULT openres;
	if (flags == ZIP_FILENAME)
		openres = open_file((const TCHAR*)src);
	else if (flags == ZIP_HANDLE)
		openres = open_handle((HANDLE)src, len);
	else if (flags == ZIP_MEMORY)
		openres = open_mem(src, len);
	else if (flags == ZIP_FOLDER)
		openres = open_dir();
	else return ZR_ARGS;
	if (openres != ZR_OK)
		return openres;

	// A zip "entry" consists of a local header (which includes the file name),
	// then the compressed data, and possibly an extended local header.

	// Initialize the local header
	TZipFileInfo zfi; zfi.nxt = NULL;
	strcpy(zfi.name, "");
	strcpy(zfi.iname, dstzn);
	zfi.nam = strlen(zfi.iname);
	if (needs_trailing_slash)
	{
		strcat(zfi.iname, "/");
		zfi.nam++;
	}
	strcpy(zfi.zname, "");
	zfi.extra = NULL; zfi.ext = 0;   // extra header to go after this compressed data, and its length
	zfi.cextra = NULL; zfi.cext = 0; // extra header to go in the central end-of-zip directory, and its length
	zfi.comment = NULL; zfi.com = 0; // comment, and its length
	zfi.mark = 1;
	zfi.dosflag = 0;
	zfi.att = (ush)BINARY;
	zfi.vem = (ush)0xB17; // 0xB00 is win32 os-code. 0x17 is 23 in decimal: zip 2.3
	zfi.ver = (ush)20;    // Needs PKUNZIP 2.0 to unzip it
	zfi.tim = timestamp;
	// Even though we write the header now, it will have to be rewritten, since we don't know compressed size or crc.
	zfi.crc = 0;            // to be updated later
	zfi.flg = 8;            // 8 means 'there is an extra header'. Assume for the moment that we need it.
	zfi.lflg = zfi.flg;     // to be updated later
	zfi.how = (ush)method;  // to be updated later
	zfi.siz = (ulg)(method == STORE && isize >= 0 ? isize : 0); // to be updated later
	zfi.len = (ulg)(isize);  // to be updated later
	zfi.dsk = 0;
	zfi.atx = attr;
	zfi.off = writ + ooffset;         // offset within file of the start of this local record
	// stuff the 'times' structure into zfi.extra
	char xloc[EB_L_UT_SIZE];
	zfi.extra = xloc;
	zfi.ext = EB_L_UT_SIZE;
	char xcen[EB_C_UT_SIZE];
	zfi.cextra = xcen;
	zfi.cext = EB_C_UT_SIZE;
	xloc[0] = 'U';
	xloc[1] = 'T';
	xloc[2] = EB_UT_LEN(3);       // length of data part of e.f.
	xloc[3] = 0;
	xloc[4] = EB_UT_FL_MTIME | EB_UT_FL_ATIME | EB_UT_FL_CTIME;
	xloc[5] = (char)(times.mtime);
	xloc[6] = (char)(times.mtime >> 8);
	xloc[7] = (char)(times.mtime >> 16);
	xloc[8] = (char)(times.mtime >> 24);
	xloc[9] = (char)(times.atime);
	xloc[10] = (char)(times.atime >> 8);
	xloc[11] = (char)(times.atime >> 16);
	xloc[12] = (char)(times.atime >> 24);
	xloc[13] = (char)(times.ctime);
	xloc[14] = (char)(times.ctime >> 8);
	xloc[15] = (char)(times.ctime >> 16);
	xloc[16] = (char)(times.ctime >> 24);
	memcpy(zfi.cextra, zfi.extra, EB_C_UT_SIZE);
	zfi.cextra[EB_LEN] = EB_UT_LEN(1);


	// (1) Start by writing the local header:
	int r = putlocal(&zfi, swrite, this);
	if (r != ZE_OK)
	{
		iclose();
		return ZR_WRITE;
	}
	writ += 4 + LOCHEAD + (unsigned int)zfi.nam + (unsigned int)zfi.ext;
	if (oerr != ZR_OK)
	{
		iclose();
		return oerr;
	}

	//(2) Write deflated/stored file to zip file
	ZRESULT writeres = ZR_OK;
	if (!isdir && method == DEFLATE)
		writeres = ideflate(&zfi);
	else if (!isdir && method == STORE)
		writeres = istore();
	else if (isdir)
		csize = 0;
	iclose();
	writ += csize;
	if (oerr != ZR_OK)
		return oerr;
	if (writeres != ZR_OK)
		return ZR_WRITE;

	// (3) Either rewrite the local header with correct information...
	bool first_header_has_size_right = (zfi.siz == csize);
	zfi.crc = crc;
	zfi.siz = csize;
	zfi.len = isize;
	if (ocanseek)
	{
		zfi.how = (ush)method;
		if ((zfi.flg & 1) == 0)
			zfi.flg &= ~8; // clear the extended local header flag
		zfi.lflg = zfi.flg;
		// rewrite the local header:
		if (!oseek(zfi.off - ooffset))
			return ZR_SEEK;
		if ((r = putlocal(&zfi, swrite, this)) != ZE_OK)
			return ZR_WRITE;
		if (!oseek(writ))
			return ZR_SEEK;
	}
	else
	{
		// (4) ... or put an updated header at the end
		if (zfi.how != (ush)method)
			return ZR_NOCHANGE;
		if (method == STORE && !first_header_has_size_right)
			return ZR_NOCHANGE;
		if ((r = putextended(&zfi, swrite, this)) != ZE_OK)
			return ZR_WRITE;
		writ += 16L;
		zfi.flg = zfi.lflg; // if flg modified by inflate, for the central index
	}
	if (oerr != ZR_OK)
		return oerr;

	// Keep a copy of the zipfileinfo, for our end-of-zip directory
	char *cextra = new char[zfi.cext];
	memcpy(cextra, zfi.cextra, zfi.cext); zfi.cextra = cextra;
	TZipFileInfo *pzfi = new TZipFileInfo;
	memcpy(pzfi, &zfi, sizeof(zfi));
	if (zfis == NULL)
		zfis = pzfi;
	else
	{
		TZipFileInfo *z = zfis;
		while (z->nxt != NULL)
			z = z->nxt;
		z->nxt = pzfi;
	}
	return ZR_OK;
}

ZRESULT TZip::AddCentral()
{ // write central directory
	int numentries = 0;
	ulg pos_at_start_of_central = writ;
	//ulg tot_unc_size=0, tot_compressed_size=0;
	bool okay = true;
	for (TZipFileInfo *zfi = zfis; zfi != NULL;)
	{
		if (okay)
		{
			int res = putcentral(zfi, swrite, this);
			if (res != ZE_OK) okay = false;
		}
		writ += 4 + CENHEAD + (unsigned int)zfi->nam + (unsigned int)zfi->cext + (unsigned int)zfi->com;
		//tot_unc_size += zfi->len;
		//tot_compressed_size += zfi->siz;
		numentries++;
		//
		TZipFileInfo *zfinext = zfi->nxt;
		if (zfi->cextra != 0) delete[] zfi->cextra;
		delete zfi;
		zfi = zfinext;
	}
	ulg center_size = writ - pos_at_start_of_central;
	if (okay)
	{
		int res = putend(numentries, center_size, pos_at_start_of_central + ooffset, 0, NULL, swrite, this);
		if (res != ZE_OK) okay = false;
		writ += 4 + ENDHEAD + 0;
	}
	if (!okay) return ZR_WRITE;
	return ZR_OK;
}





ZRESULT lasterrorZ = ZR_OK;

unsigned int FormatZipMessageZ(ZRESULT code, char *buf, unsigned int len)
{
	if (code == ZR_RECENT) code = lasterrorZ;
	const char *msg = "unknown zip result code";
	switch (code)
	{
	case ZR_OK: msg = "Success"; break;
	case ZR_NODUPH: msg = "Culdn't duplicate handle"; break;
	case ZR_NOFILE: msg = "Couldn't create/open file"; break;
	case ZR_NOALLOC: msg = "Failed to allocate memory"; break;
	case ZR_WRITE: msg = "Error writing to file"; break;
	case ZR_NOTFOUND: msg = "File not found in the zipfile"; break;
	case ZR_MORE: msg = "Still more data to unzip"; break;
	case ZR_CORRUPT: msg = "Zipfile is corrupt or not a zipfile"; break;
	case ZR_READ: msg = "Error reading file"; break;
	case ZR_ARGS: msg = "Caller: faulty arguments"; break;
	case ZR_PARTIALUNZ: msg = "Caller: the file had already been partially unzipped"; break;
	case ZR_NOTMMAP: msg = "Caller: can only get memory of a memory zipfile"; break;
	case ZR_MEMSIZE: msg = "Caller: not enough space allocated for memory zipfile"; break;
	case ZR_FAILED: msg = "Caller: there was a previous error"; break;
	case ZR_ENDED: msg = "Caller: additions to the zip have already been ended"; break;
	case ZR_ZMODE: msg = "Caller: mixing creation and opening of zip"; break;
	case ZR_NOTINITED: msg = "Zip-bug: internal initialisation not completed"; break;
	case ZR_SEEK: msg = "Zip-bug: trying to seek the unseekable"; break;
	case ZR_MISSIZE: msg = "Zip-bug: the anticipated size turned out wrong"; break;
	case ZR_NOCHANGE: msg = "Zip-bug: tried to change mind, but not allowed"; break;
	case ZR_FLATE: msg = "Zip-bug: an internal error during flation"; break;
	}
	unsigned int mlen = (unsigned int)strlen(msg);
	if (buf == 0 || len == 0) return mlen;
	unsigned int n = mlen; if (n + 1>len) n = len - 1;
	strncpy(buf, msg, n); buf[n] = 0;
	return mlen;
}



typedef struct
{
	DWORD flag;
	TZip *zip;
} TZipHandleData;


HZIP CreateZipZ(void *z, unsigned int len, DWORD flags)
{
	tzset();
	TZip *zip = new TZip();
	lasterrorZ = zip->Create(z, len, flags);
	if (lasterrorZ != ZR_OK)
	{
		delete zip;
		return 0;
	}
	TZipHandleData *han = new TZipHandleData;
	han->flag = 2;
	han->zip = zip;
	return (HZIP)han;
}

ZRESULT ZipAdd(HZIP hz, const CHAR *dstzn, void *src, unsigned int len, DWORD flags)
{
	if (hz == 0)
	{
		lasterrorZ = ZR_ARGS;
		return ZR_ARGS;
	}
	TZipHandleData *han = (TZipHandleData*)hz;
	if (han->flag != 2)
	{
		lasterrorZ = ZR_ZMODE;
		return ZR_ZMODE;
	}
	TZip *zip = han->zip;

	char szDest[MAX_PATH * 2];
	memset(szDest, 0, sizeof(szDest));

	strcpy(szDest, dstzn);

	if (flags == ZIP_FILENAME)
	{
		lasterrorZ = zip->Add(szDest, src, len, flags);
	}
	else
	{
		lasterrorZ = zip->Add(szDest, src, len, flags);
	}

	return lasterrorZ;
}

ZRESULT ZipGetMemory(HZIP hz, void **buf, unsigned long *len)
{
	if (hz == 0) { if (buf != 0) *buf = 0; if (len != 0) *len = 0; lasterrorZ = ZR_ARGS; return ZR_ARGS; }
	TZipHandleData *han = (TZipHandleData*)hz;
	if (han->flag != 2) { lasterrorZ = ZR_ZMODE; return ZR_ZMODE; }
	TZip *zip = han->zip;
	lasterrorZ = zip->GetMemory(buf, len);
	return lasterrorZ;
}

ZRESULT CloseZipZ(HZIP hz)
{
	if (hz == 0) { lasterrorZ = ZR_ARGS; return ZR_ARGS; }
	TZipHandleData *han = (TZipHandleData*)hz;
	if (han->flag != 2) { lasterrorZ = ZR_ZMODE; return ZR_ZMODE; }
	TZip *zip = han->zip;
	lasterrorZ = zip->Close();
	delete zip;
	delete han;
	return lasterrorZ;
}

bool IsZipHandleZ(HZIP hz)
{
	if (hz == 0) return true;
	TZipHandleData *han = (TZipHandleData*)hz;
	return (han->flag == 2);
}

//+++1.2
/**
* Added by Renaud Deysine. This fonctionnality was missing in API
* @brief Add a folder to the zip file. Empty folders will also be added.
* This method add recursively the content of a directory
* @param AbsolutePath like "C:\\Windows" or "C:\\Windows\"
* @param DirToAdd like "System32"
*
*/
BOOL AddFolderContent(HZIP hZip, CHAR* AbsolutePath, CHAR* DirToAdd)
{
	HANDLE hFind; // file handle
	WIN32_FIND_DATAA FindFileData;
	CHAR PathToSearchInto[MAX_PATH] = { 0 };

	if (NULL != DirToAdd)
	{
		ZipAdd(hZip, DirToAdd, 0, 0, ZIP_FOLDER);
	}

	// Construct the path to search into "C:\\Windows\\System32\\*"
	strcpy(PathToSearchInto, AbsolutePath);
	strcat(PathToSearchInto, "\\");
	strcat(PathToSearchInto, DirToAdd);
	strcat(PathToSearchInto, "\\*");

	hFind = FindFirstFileA(PathToSearchInto, &FindFileData); // find the first file
	if (hFind == INVALID_HANDLE_VALUE)
	{
		return FALSE;
	}

	bool bSearch = true;
	while (bSearch) // until we finds an entry
	{
		if (FindNextFileA(hFind, &FindFileData))
		{
			// Don't care about . and ..
			//if(IsDots(FindFileData.cFileName))
			if ((strcmp(FindFileData.cFileName, ".") == 0) ||
				(strcmp(FindFileData.cFileName, "..") == 0))
				continue;

			// We have found a directory
			if ((FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY))
			{
				CHAR RelativePathNewDirFound[MAX_PATH] = { 0 };
				strcat(RelativePathNewDirFound, DirToAdd);
				strcat(RelativePathNewDirFound, "\\");
				strcat(RelativePathNewDirFound, FindFileData.cFileName);

				// Recursive call with the new directory found
				if (AddFolderContent(hZip, AbsolutePath, RelativePathNewDirFound) == FALSE)
				{
					return FALSE;
				}

			}
			// We have found a file
			else
			{
				// Add the found file to the zip file
				CHAR RelativePathNewFileFound[MAX_PATH] = { 0 };
				strcpy(RelativePathNewFileFound, AbsolutePath);
				strcat(RelativePathNewFileFound, DirToAdd);
				strcat(RelativePathNewFileFound, "\\");
				strcat(RelativePathNewFileFound, FindFileData.cFileName);

				if (ZipAdd(hZip, RelativePathNewFileFound + strlen(AbsolutePath), RelativePathNewFileFound, 0, ZIP_FILENAME) != ZR_OK)
				{
					return FALSE;
				}
			}

		}//FindNextFile
		else
		{
			if (GetLastError() == ERROR_NO_MORE_FILES) // no more files there
				bSearch = false;
			else {
				// some error occured, close the handle and return FALSE
				FindClose(hFind);
				return FALSE;
			}
		}
	}//while

	FindClose(hFind); // closing file handle
	return true;

}

}
}