[p5sagit/p5-mst-13.2.git] / ext / Compress / Zlib / Zlib.xs

/* Filename: Zlib.xs
 * Author  : Paul Marquess, <pmqs@cpan.org>
 * Created : 22nd January 1996
 * Version : 2.000
 *
 *   Copyright (c) 1995-2005 Paul Marquess. All rights reserved.
 *   This program is free software; you can redistribute it and/or
 *   modify it under the same terms as Perl itself.
 *
 */

/* Parts of this code are based on the files gzio.c and gzappend.c from 
 * the standard zlib source distribution. Below are the copyright statements
 * from each. 
 */

/* gzio.c -- IO on .gz files
 * Copyright (C) 1995 Jean-loup Gailly.
 * For conditions of distribution and use, see copyright notice in zlib.h
 */

/* gzappend -- command to append to a gzip file

  Copyright (C) 2003 Mark Adler, all rights reserved
  version 1.1, 4 Nov 2003
*/


#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <zlib.h> 


#if  defined(ZLIB_VERNUM) && ZLIB_VERNUM >= 0x1210
#  define MAGIC_APPEND
#endif

#if  defined(ZLIB_VERNUM) && ZLIB_VERNUM >= 0x1221
#  define AT_LEAST_ZLIB_1_2_2_1
#endif

#if  defined(ZLIB_VERNUM) && ZLIB_VERNUM >= 0x1223
#  define AT_LEAST_ZLIB_1_2_2_3
#endif

#if  defined(ZLIB_VERNUM) && ZLIB_VERNUM >= 0x1230
#  define AT_LEAST_ZLIB_1_2_3
#endif

#if 0

#  include "ppport.h"

#else

/* zlib prior to 1.06 doesn't know about z_off_t */
#ifndef z_off_t
#  define z_off_t   long
#endif

#  ifndef PERL_VERSION
#    include "patchlevel.h"
#    define PERL_REVISION       5
#    define PERL_VERSION        PATCHLEVEL
#    define PERL_SUBVERSION     SUBVERSION
#  endif

#  if PERL_REVISION == 5 && (PERL_VERSION < 4 || (PERL_VERSION == 4 && PERL_SUBVERSION <= 75 ))

#      define PL_sv_undef       sv_undef
#      define PL_na             na
#      define PL_curcop         curcop
#      define PL_compiling      compiling

#  endif

#  ifndef newSVuv
#      define newSVuv   newSViv
#  endif

#endif


#if PERL_REVISION == 5 && (PERL_VERSION >= 8 || (PERL_VERSION == 8 && PERL_SUBVERSION < 4 ))
#    define UTF8_AVAILABLE
#endif

#if PERL_REVISION == 5 && (PERL_VERSION < 8 || (PERL_VERSION == 8 && PERL_SUBVERSION < 4 ))

#    ifdef SvPVbyte_force
#        undef SvPVbyte_force
#    endif

#    define SvPVbyte_force(sv,lp) SvPV_force(sv,lp)

#endif

#ifndef SvPVbyte_nolen
#    define SvPVbyte_nolen SvPV_nolen
#endif

#ifndef SvPVbyte
#    define SvPVbyte SvPV
#endif

#ifndef dTHX
#    define dTHX 
#endif

#ifndef SvPV_nolen

#define sv_2pv_nolen(a) my_sv_2pv_nolen(a)

static char *
my_sv_2pv_nolen(register SV *sv)
{   
  STRLEN n_a;
  return sv_2pv(sv, &n_a);
}


/* SvPV_nolen depends on sv_2pv_nolen */
#define SvPV_nolen(sv) \
          ((SvFLAGS(sv) & (SVf_POK)) == SVf_POK \
           ? SvPVX(sv) : sv_2pv_nolen(sv))


#endif

#ifndef SvGETMAGIC
#  define SvGETMAGIC(x)                  STMT_START { if (SvGMAGICAL(x)) mg_get(x); } STMT_END
#endif

typedef int                     DualType ;
typedef int                     int_undef ;

typedef struct di_stream {
    int      flags ;
#define FLAG_APPEND             1
#define FLAG_CRC32              2
#define FLAG_ADLER32            4
#define FLAG_CONSUME_INPUT      8
    uLong    crc32 ;
    uLong    adler32 ;
    z_stream stream;
    uLong     bufsize; 
    uLong     bufinc; 
    SV *     dictionary ;
    uLong    dict_adler ;
    int      last_error ;
    bool     zip_mode ;
#define SETP_BYTE
#ifdef SETP_BYTE
    bool     deflateParams_out_valid ;
    Bytef    deflateParams_out_byte;
#else
#define deflateParams_BUFFER_SIZE       0x4000
    uLong    deflateParams_out_length;
    Bytef*   deflateParams_out_buffer;
#endif
    int      Level;
    int      Method;
    int      WindowBits;
    int      MemLevel;
    int      Strategy;
    uLong    bytesInflated ;
#ifdef MAGIC_APPEND

#define WINDOW_SIZE 32768U

    bool     matchedEndBlock;
    Bytef*   window ;
    int      window_lastbit,  window_left,  window_full;
    unsigned window_have;
    off_t    window_lastoff, window_end;
    off_t    window_endOffset;

    uLong    lastBlockOffset ;
    unsigned char window_lastByte ;
                

#endif
} di_stream;

typedef di_stream * deflateStream ;
typedef di_stream * Compress__Zlib__deflateStream ;
typedef di_stream * inflateStream ;
typedef di_stream * Compress__Zlib__inflateStream ;
typedef di_stream * Compress__Zlib__inflateScanStream ;

#define GZERRNO "Compress::Zlib::gzerrno"

#define ZMALLOC(to, typ) ((to = (typ *)safemalloc(sizeof(typ))), \
                                Zero(to,1,typ))

/* Figure out the Operating System */
#ifdef MSDOS
#  define OS_CODE  0x00
#endif

#if defined(AMIGA) || defined(AMIGAOS) 
#  define OS_CODE  0x01
#endif
 
#if defined(VAXC) || defined(VMS)
#  define OS_CODE  0x02
#endif

#if 0 /* VM/CMS */
#  define OS_CODE  0x04
#endif
 
#if defined(ATARI) || defined(atarist)
#  define OS_CODE  0x05
#endif
 
#ifdef OS2
#  define OS_CODE  0x06
#endif
 
#if defined(MACOS) || defined(TARGET_OS_MAC)
#  define OS_CODE  0x07
#endif

#if 0 /* Z-System */
#  define OS_CODE  0x08
#endif
 
#if 0 /* CP/M */
#  define OS_CODE  0x09
#endif
 
#ifdef TOPS20
#  define OS_CODE  0x0a
#endif

#ifdef WIN32 /* Window 95 & Windows NT */
#  define OS_CODE  0x0b
#endif
 
#if 0 /* QDOS */
#  define OS_CODE  0x0c
#endif
 
#if 0 /* Acorn RISCOS */
#  define OS_CODE  0x0d
#endif
 
#if 0 /* ???  */
#  define OS_CODE  0x0e
#endif
 
#ifdef __50SERIES /* Prime/PRIMOS */
#  define OS_CODE  0x0F
#endif
 
/* Default to UNIX */ 
#ifndef OS_CODE
#  define OS_CODE  0x03  /* assume Unix */
#endif

#ifndef GZIP_OS_CODE
#  define GZIP_OS_CODE OS_CODE
#endif

#define adlerInitial adler32(0L, Z_NULL, 0)
#define crcInitial crc32(0L, Z_NULL, 0)


static const char * const my_z_errmsg[] = {
    "need dictionary",     /* Z_NEED_DICT     2 */
    "stream end",          /* Z_STREAM_END    1 */
    "",                    /* Z_OK            0 */
    "file error",          /* Z_ERRNO        (-1) */
    "stream error",        /* Z_STREAM_ERROR (-2) */
    "data error",          /* Z_DATA_ERROR   (-3) */
    "insufficient memory", /* Z_MEM_ERROR    (-4) */
    "buffer error",        /* Z_BUF_ERROR    (-5) */
    "incompatible version",/* Z_VERSION_ERROR(-6) */
    ""};

#define setDUALstatus(var, err)                                         \
                sv_setnv(var, (double)err) ;                            \
                sv_setpv(var, ((err) ? GetErrorString(err) : "")) ;     \
                SvNOK_on(var);

   
#if defined(__SYMBIAN32__)
# define NO_WRITEABLE_DATA
#endif

#define TRACE_DEFAULT 0

#ifdef NO_WRITEABLE_DATA
#  define trace TRACE_DEFAULT
#else
  static int trace = TRACE_DEFAULT ;
#endif

/* Dodge PerlIO hiding of these functions. */
#undef printf

static char *
#ifdef CAN_PROTOTYPE
GetErrorString(int error_no)
#else
GetErrorString(error_no)
int error_no ;
#endif
{
    dTHX;
    char * errstr ;
  
    if (error_no == Z_ERRNO) {
        errstr = Strerror(errno) ;
    }
    else
        /* errstr = gzerror(fil, &error_no) ; */
        errstr = (char*) my_z_errmsg[2 - error_no]; 

    return errstr ;
}

#if 0
static void
#ifdef CAN_PROTOTYPE
SetGzErrorNo(int error_no)
#else
SetGzErrorNo(error_no)
int error_no ;
#endif
{
    char * errstr ;
    SV * gzerror_sv = perl_get_sv(GZERRNO, FALSE) ;
  
    if (error_no == Z_ERRNO) {
        error_no = errno ;
        errstr = Strerror(errno) ;
    }
    else
        /* errstr = gzerror(fil, &error_no) ; */
        errstr = (char*) my_z_errmsg[2 - error_no]; 

    if (SvIV(gzerror_sv) != error_no) {
        sv_setiv(gzerror_sv, error_no) ;
        sv_setpv(gzerror_sv, errstr) ;
        SvIOK_on(gzerror_sv) ;
    }

}


static void
#ifdef CAN_PROTOTYPE
SetGzError(gzFile file)
#else
SetGzError(file)
gzFile file ;
#endif
{
    int error_no ;

    (void)gzerror(file, &error_no) ;
    SetGzErrorNo(error_no) ;
}

#endif

#ifdef MAGIC_APPEND

/*
   The following two functions are taken almost directly from
   examples/gzappend.c. Only cosmetic changes have been made to conform to
   the coding style of the rest of the code in this file.
*/


/* return the greatest common divisor of a and b using Euclid's algorithm,
   modified to be fast when one argument much greater than the other, and
   coded to avoid unnecessary swapping */
static unsigned 
#ifdef CAN_PROTOTYPE
gcd(unsigned a, unsigned b)
#else
gcd(a, b)
    unsigned a;
    unsigned b;
#endif
{
    unsigned c;

    while (a && b)
        if (a > b) {
            c = b;
            while (a - c >= c)
                c <<= 1;
            a -= c;
        }
        else {
            c = a;
            while (b - c >= c)
                c <<= 1;
            b -= c;
        }
    return a + b;
}

/* rotate list[0..len-1] left by rot positions, in place */
static void 
#ifdef CAN_PROTOTYPE
rotate(unsigned char *list, unsigned len, unsigned rot)
#else
rotate(list, len, rot)
    unsigned char *list;
    unsigned len ;
    unsigned rot;
#endif
{
    unsigned char tmp;
    unsigned cycles;
    unsigned char *start, *last, *to, *from;

    /* normalize rot and handle degenerate cases */
    if (len < 2) return;
    if (rot >= len) rot %= len;
    if (rot == 0) return;

    /* pointer to last entry in list */
    last = list + (len - 1);

    /* do simple left shift by one */
    if (rot == 1) {
        tmp = *list;
        memcpy(list, list + 1, len - 1);
        *last = tmp;
        return;
    }

    /* do simple right shift by one */
    if (rot == len - 1) {
        tmp = *last;
        memmove(list + 1, list, len - 1);
        *list = tmp;
        return;
    }

    /* otherwise do rotate as a set of cycles in place */
    cycles = gcd(len, rot);             /* number of cycles */
    do {
        start = from = list + cycles;   /* start index is arbitrary */
        tmp = *from;                    /* save entry to be overwritten */
        for (;;) {
            to = from;                  /* next step in cycle */
            from += rot;                /* go right rot positions */
            if (from > last) from -= len;   /* (pointer better not wrap) */
            if (from == start) break;   /* all but one shifted */
            *to = *from;                /* shift left */
        }
        *to = tmp;                      /* complete the circle */
    } while (--cycles);
}

#endif /* MAGIC_APPEND */

static void
#ifdef CAN_PROTOTYPE
DispHex(void * ptr, int length)
#else
DispHex(ptr, length)
    void * ptr;
    int length;
#endif
{
    char * p = (char*)ptr;
    int i;
    for (i = 0; i < length; ++i) {
        printf(" %02x", 0xFF & *(p+i));
    }
}


static void
#ifdef CAN_PROTOTYPE
DispStream(di_stream * s, char * message)
#else
DispStream(s, message)
    di_stream * s;
    char * message;
#endif
{

#if 0
    if (! trace)
        return ;
#endif

#define EnDis(f) (s->flags & f ? "Enabled" : "Disabled")

    printf("DispStream 0x%p", s) ;
    if (message)
        printf("- %s \n", message) ;
    printf("\n") ;

    if (!s)  {
        printf("    stream pointer is NULL\n");
    }
    else     {
        printf("    stream           0x%p\n", &(s->stream));
        printf("           zalloc    0x%p\n", s->stream.zalloc);
        printf("           zfree     0x%p\n", s->stream.zfree);
        printf("           opaque    0x%p\n", s->stream.opaque);
        if (s->stream.msg)
            printf("           msg       %s\n", s->stream.msg);
        else
            printf("           msg       \n");
        printf("           next_in   0x%p", s->stream.next_in);
        if (s->stream.next_in){
            printf(" =>");
            DispHex(s->stream.next_in, 4);
        }
        printf("\n");

        printf("           next_out  0x%p", s->stream.next_out);
        if (s->stream.next_out){
            printf(" =>");
            DispHex(s->stream.next_out, 4);
        }
        printf("\n");

        printf("           avail_in  %lu\n",  (unsigned long)s->stream.avail_in);
        printf("           avail_out %lu\n",  (unsigned long)s->stream.avail_out);
        printf("           total_in  %ld\n",  s->stream.total_in);
        printf("           total_out %ld\n",  s->stream.total_out);
        printf("           adler     %ld\n",  s->stream.adler    );
        printf("    bufsize          %ld\n",  s->bufsize);
        printf("    dictionary       0x%p\n", s->dictionary);
        printf("    dict_adler       0x%ld\n",s->dict_adler);
        printf("    zip_mode         %d\n",   s->zip_mode);
        printf("    crc32            0x%x\n", (unsigned)s->crc32);
        printf("    adler32          0x%x\n", (unsigned)s->adler32);
        printf("    flags            0x%x\n", s->flags);
        printf("           APPEND    %s\n",   EnDis(FLAG_APPEND));
        printf("           CRC32     %s\n",   EnDis(FLAG_CRC32));
        printf("           ADLER32   %s\n",   EnDis(FLAG_ADLER32));
        printf("           CONSUME   %s\n",   EnDis(FLAG_CONSUME_INPUT));

#ifdef MAGIC_APPEND
        printf("    window           0x%p\n", s->window);
#endif
        printf("\n");

    }
}

static di_stream *
#ifdef CAN_PROTOTYPE
InitStream(void)
#else
InitStream()
#endif
{
    di_stream *s ;

    ZMALLOC(s, di_stream) ;

    return s ;
    
}

static void
#ifdef CAN_PROTOTYPE
PostInitStream(di_stream * s, int flags, int bufsize, int windowBits)
#else
PostInitStream(s, flags, bufsize, windowBits)
    di_stream *s ;
    int flags ;
    int bufsize ;
    int windowBits ;
#endif
{
    s->bufsize = bufsize ;
    s->bufinc  = bufsize ;
    s->last_error = 0 ;
    s->flags    = flags ;
    s->zip_mode = (windowBits < 0) ;
    if (flags & FLAG_CRC32) 
        s->crc32 = crcInitial ;
    if (flags & FLAG_ADLER32) 
        s->adler32 = adlerInitial ;
}


static SV* 
#ifdef CAN_PROTOTYPE
deRef(SV * sv, char * string)
#else
deRef(sv, string)
SV * sv ;
char * string;
#endif
{
    dTHX;
    SvGETMAGIC(sv);

    if (SvROK(sv)) {
        sv = SvRV(sv) ;
        SvGETMAGIC(sv);
        switch(SvTYPE(sv)) {
            case SVt_PVAV:
            case SVt_PVHV:
            case SVt_PVCV:
                croak("%s: buffer parameter is not a SCALAR reference", string);
        }
        if (SvROK(sv))
            croak("%s: buffer parameter is a reference to a reference", string) ;
    }

    if (!SvOK(sv)) { 
        sv = newSVpv("", 0);
    }

    return sv ;
}

static SV*
#ifdef CAN_PROTOTYPE
deRef_l(SV * sv, char * string)
#else
deRef_l(sv, string)
SV * sv ;
char * string ;
#endif
{
    bool wipe = 0 ;
    
    SvGETMAGIC(sv);
    wipe = ! SvOK(sv) ;

    if (SvROK(sv)) {
        sv = SvRV(sv) ;
        SvGETMAGIC(sv);
        wipe = ! SvOK(sv) ;

        switch(SvTYPE(sv)) {
            case SVt_PVAV:
            case SVt_PVHV:
            case SVt_PVCV:
                croak("%s: buffer parameter is not a SCALAR reference", string);
        }
        if (SvROK(sv))
            croak("%s: buffer parameter is a reference to a reference", string) ;
    }

    if (SvREADONLY(sv) && PL_curcop != &PL_compiling)
        croak("%s: buffer parameter is read-only", string);

    SvUPGRADE(sv, SVt_PV);

    if (wipe)
        SvCUR_set(sv, 0);
    
    SvOOK_off(sv);
    SvPOK_only(sv);

    return sv ;
}


#include "constants.h"

MODULE = Compress::Zlib PACKAGE = Compress::Zlib        PREFIX = Zip_

REQUIRE:	1.924
PROTOTYPES:	DISABLE

INCLUDE: constants.xs

BOOT:
    /* Check this version of zlib is == 1 */
    if (zlibVersion()[0] != '1')
	croak("Compress::Zlib needs zlib version 1.x\n") ;
	
    {
        /* Create the $os_code scalar */
        SV * os_code_sv = perl_get_sv("Compress::Zlib::gzip_os_code", GV_ADDMULTI) ;
        sv_setiv(os_code_sv, GZIP_OS_CODE) ;
    }

    {
        /* Create the $gzerror scalar */
        SV * gzerror_sv = perl_get_sv(GZERRNO, GV_ADDMULTI) ;
        sv_setiv(gzerror_sv, 0) ;
        sv_setpv(gzerror_sv, "") ;
        SvIOK_on(gzerror_sv) ;
    }


int
_readonly_ref(sv)
    SV* sv
    CODE:
        if (SvROK(sv)) 
            RETVAL = SvREADONLY(SvRV(sv)) ;
        else 
            RETVAL = SvREADONLY(sv) ;
    OUTPUT:
        RETVAL

void
_dualvar(num,str)
    SV *        num
    SV *        str
PROTOTYPE: $$
CODE:
{
    STRLEN len;
    char *ptr = SvPVbyte(str,len); 
    ST(0) = sv_newmortal();
    SvUPGRADE(ST(0),SVt_PVNV);
    sv_setpvn(ST(0),ptr,len);
    if(SvNOK(num) || SvPOK(num) || SvMAGICAL(num)) {
        SvNV_set(ST(0), SvNV(num));
        SvNOK_on(ST(0));
    }
#ifdef SVf_IVisUVXXXX
    else if (SvUOK(num)) {
        SvUVX(ST(0)) = SvUV(num);
        SvIOK_on(ST(0));
        SvIsUV_on(ST(0));
    }
#endif
    else {
        SvIV_set(ST(0), SvIV(num));
        SvIOK_on(ST(0));
    }
    XSRETURN(1);
}


#define Zip_zlib_version()	(char*)zlib_version
char*
Zip_zlib_version()

unsigned
ZLIB_VERNUM()
    CODE:
#ifdef ZLIB_VERNUM
        RETVAL = ZLIB_VERNUM ;
#else
        /* 1.1.4 => 0x1140 */
        RETVAL  = (ZLIB_VERSION[0] - '0') << 12 ;
        RETVAL += (ZLIB_VERSION[2] - '0') <<  8 ;
        RETVAL += (ZLIB_VERSION[4] - '0') <<  4 ;
#endif
    OUTPUT:
        RETVAL

MODULE = Compress::Zlib	PACKAGE = Compress::Zlib	PREFIX = Zip_

#define Zip_adler32(buf, adler) adler32(adler, buf, (uInt)len)

uLong
Zip_adler32(buf, adler=adlerInitial)
        uLong    adler = NO_INIT
        STRLEN   len = NO_INIT
        Bytef *  buf = NO_INIT
	SV *	 sv = ST(0) ;
	INIT:
    	/* If the buffer is a reference, dereference it */
	sv = deRef(sv, "adler32") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(sv) && !sv_utf8_downgrade(sv, 1))
         croak("Wide character in Compress::Zlib::adler32");
#endif         
	buf = (Byte*)SvPVbyte(sv, len) ;

	if (items < 2)
	  adler = adlerInitial;
	else if (SvOK(ST(1)))
	  adler = SvUV(ST(1)) ;
	else
	  adler = adlerInitial;
 
#define Zip_crc32(buf, crc) crc32(crc, buf, (uInt)len)

uLong
Zip_crc32(buf, crc=crcInitial)
        uLong    crc = NO_INIT
        STRLEN   len = NO_INIT
        Bytef *  buf = NO_INIT
	SV *	 sv = ST(0) ;
	INIT:
    	/* If the buffer is a reference, dereference it */
	sv = deRef(sv, "crc32") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(sv) && !sv_utf8_downgrade(sv, 1))
         croak("Wide character in Compress::Zlib::crc32");
#endif         
	buf = (Byte*)SvPVbyte(sv, len) ;

	if (items < 2)
	  crc = crcInitial;
	else if (SvOK(ST(1)))
	  crc = SvUV(ST(1)) ;
	else
	  crc = crcInitial;


uLong
crc32_combine(crc1, crc2, len2)
        uLong    crc1 
        uLong    crc2 
        z_off_t   len2 
	CODE:
#ifndef AT_LEAST_ZLIB_1_2_2_1
        crc1 = crc1; crc2 = crc2 ; len2 = len2; /* Silence -Wall */
        croak("crc32_combine needs zlib 1.2.3 or better");
#else
        RETVAL = crc32_combine(crc1, crc2, len2);
#endif
    OUTPUT:
        RETVAL


uLong
adler32_combine(adler1, adler2, len2)
        uLong    adler1 
        uLong    adler2 
        z_off_t   len2 
	CODE:
#ifndef AT_LEAST_ZLIB_1_2_2_1
        adler1 = adler1; adler2 = adler2 ; len2 = len2; /* Silence -Wall */
        croak("adler32_combine needs zlib 1.2.3 or better");
#else
        RETVAL = adler32_combine(adler1, adler2, len2);
#endif
    OUTPUT:
        RETVAL


MODULE = Compress::Zlib PACKAGE = Compress::Zlib

void
_deflateInit(flags,level, method, windowBits, memLevel, strategy, bufsize, dictionary)
    int flags
    int	level
    int method
    int windowBits
    int memLevel
    int strategy
    uLong bufsize
    SV* dictionary
  PPCODE:
    int err ;
    deflateStream s ;

    if (trace)
        warn("in _deflateInit(level=%d, method=%d, windowBits=%d, memLevel=%d, strategy=%d, bufsize=%ld\n",
	level, method, windowBits, memLevel, strategy, bufsize) ;
    if ((s = InitStream() )) {

        s->Level      = level;
        s->Method     = method;
        s->WindowBits = windowBits;
        s->MemLevel   = memLevel;
        s->Strategy   = strategy;

        err = deflateInit2(&(s->stream), level, 
			   method, windowBits, memLevel, strategy);

	/* Check if a dictionary has been specified */

	if (err == Z_OK && SvCUR(dictionary)) {
#ifdef UTF8_AVAILABLE    
        if (DO_UTF8(dictionary) && !sv_utf8_downgrade(dictionary, 1))
             croak("Wide character in Compress::Zlib::Deflate::new dicrionary parameter");
#endif         
	    err = deflateSetDictionary(&(s->stream), (const Bytef*) SvPVbyte_nolen(dictionary), 
					SvCUR(dictionary)) ;
	    s->dict_adler = s->stream.adler ;
	}

        if (err != Z_OK) {
            Safefree(s) ;
            s = NULL ;
	}
	else
	    PostInitStream(s, flags, bufsize, windowBits) ;
        
    }
    else
        err = Z_MEM_ERROR ;

    XPUSHs(sv_setref_pv(sv_newmortal(), 
	"Compress::Zlib::deflateStream", (void*)s));
    if (GIMME == G_ARRAY) {
        SV * sv = sv_2mortal(newSViv(err)) ;
	setDUALstatus(sv, err);
        XPUSHs(sv) ;
    }

void
_inflateInit(flags, windowBits, bufsize, dictionary)
    int flags
    int windowBits
    uLong bufsize
    SV * dictionary
  ALIAS:
    _inflateScanInit = 1
  PPCODE:
 
    int err = Z_OK ;
    inflateStream s ;
#ifndef MAGIC_APPEND
    if (ix == 1)
        croak("inflateScanInit needs zlib 1.2.1 or better");
#endif
    if (trace)
        warn("in _inflateInit(windowBits=%d, bufsize=%lu, dictionary=%lu\n",
                windowBits, bufsize, (unsigned long)SvCUR(dictionary)) ;
    if ((s = InitStream() )) {

        s->WindowBits = windowBits;

        err = inflateInit2(&(s->stream), windowBits);
        if (err != Z_OK) {
            Safefree(s) ;
            s = NULL ;
	}
	else if (SvCUR(dictionary)) {
            /* Dictionary specified - take a copy for use in inflate */
	    s->dictionary = newSVsv(dictionary) ;
	}
	if (s) {
	    PostInitStream(s, flags, bufsize, windowBits) ;
#ifdef MAGIC_APPEND
            if (ix == 1)
            {
                s->window = (unsigned char *)safemalloc(WINDOW_SIZE);
            }
#endif
        }
    }
    else
	err = Z_MEM_ERROR ;

    XPUSHs(sv_setref_pv(sv_newmortal(), 
                   ix == 1 
                   ? "Compress::Zlib::inflateScanStream" 
                   :  "Compress::Zlib::inflateStream",
                   (void*)s));
    if (GIMME == G_ARRAY) {
        SV * sv = sv_2mortal(newSViv(err)) ;
	setDUALstatus(sv, err);
        XPUSHs(sv) ;
    }
 

MODULE = Compress::Zlib PACKAGE = Compress::Zlib::deflateStream

void
DispStream(s, message=NULL)
    Compress::Zlib::deflateStream   s
    char *  message

DualType
deflateReset(s)
    Compress::Zlib::deflateStream   s
  CODE:
      RETVAL = deflateReset(&(s->stream)) ;
      if (RETVAL == Z_OK) {
	  PostInitStream(s, s->flags, s->bufsize, s->WindowBits) ;
      }
    OUTPUT:
      RETVAL

DualType 
deflate (s, buf, output)
    Compress::Zlib::deflateStream	s
    SV *	buf
    SV * 	output 
    uInt	cur_length = NO_INIT
    uInt	increment = NO_INIT
    int		RETVAL = 0;
  CODE:

    /* If the input buffer is a reference, dereference it */
    buf = deRef(buf, "deflate") ;
 
    /* initialise the input buffer */
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(buf) && !sv_utf8_downgrade(buf, 1))
         croak("Wide character in Compress::Zlib::Deflate::deflate input parameter");
#endif         
    s->stream.next_in = (Bytef*)SvPVbyte(buf, *(STRLEN*)&s->stream.avail_in) ;
    /* s->stream.avail_in = SvCUR(buf) ; */
    
    if (s->flags & FLAG_CRC32)
        s->crc32 = crc32(s->crc32, s->stream.next_in, s->stream.avail_in) ;

    if (s->flags & FLAG_ADLER32)
        s->adler32 = adler32(s->adler32, s->stream.next_in, s->stream.avail_in) ;

    /* and retrieve the output buffer */
    output = deRef_l(output, "deflate") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(output) && !sv_utf8_downgrade(output, 1))
         croak("Wide character in Compress::Zlib::Deflate::deflate output parameter");
#endif         

    if((s->flags & FLAG_APPEND) != FLAG_APPEND) {
        SvCUR_set(output, 0);
        /* sv_setpvn(output, "", 0); */
    }
    cur_length =  SvCUR(output) ;
    s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length;
    increment =  SvLEN(output) -  cur_length;
    s->stream.avail_out =  increment;
#ifdef SETP_BYTE
    /* Check for saved output from deflateParams */
    if (s->deflateParams_out_valid) {
	*(s->stream.next_out) = s->deflateParams_out_byte;
	++ s->stream.next_out;
	-- s->stream.avail_out ;
	s->deflateParams_out_valid = FALSE;
    }
#else
    /* Check for saved output from deflateParams */
    if (s->deflateParams_out_length) {
        uLong plen = s->deflateParams_out_length ;
        /* printf("Copy %d bytes saved data\n", plen);*/
        if (s->stream.avail_out < plen) {
            /*printf("GROW from %d to %d\n", s->stream.avail_out,
                        SvLEN(output) + plen - s->stream.avail_out); */
            Sv_Grow(output, SvLEN(output) + plen - s->stream.avail_out) ;
        }
        
        Copy(s->stream.next_out, s->deflateParams_out_buffer, plen, Bytef) ;	
        cur_length = cur_length + plen;
        SvCUR_set(output, cur_length);
	s->stream.next_out += plen ;
	s->stream.avail_out = SvLEN(output) - cur_length ;
	increment = s->stream.avail_out;
	s->deflateParams_out_length = 0;
    }
#endif
    while (s->stream.avail_in != 0) {

        if (s->stream.avail_out == 0) {
	    /* out of space in the output buffer so make it bigger */
            s->bufinc *= 2 ;
            Sv_Grow(output, SvLEN(output) + s->bufinc) ;
            cur_length += increment ;
            s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length ;
            increment = s->bufinc ;
            s->stream.avail_out = increment;
        }

        RETVAL = deflate(&(s->stream), Z_NO_FLUSH);
        if (RETVAL != Z_OK) 
            break;
    }

    s->last_error = RETVAL ;
    if (RETVAL == Z_OK) {
        SvPOK_only(output);
        SvCUR_set(output, cur_length + increment - s->stream.avail_out) ;
    }
    OUTPUT:
	RETVAL
	output
  

void
DESTROY(s)
    Compress::Zlib::deflateStream	s
  CODE:
    deflateEnd(&s->stream) ;
    if (s->dictionary)
	SvREFCNT_dec(s->dictionary) ;
#ifndef SETP_BYTE
    if (s->deflateParams_out_buffer)
        Safefree(s->deflateParams_out_buffer);
#endif
    Safefree(s) ;


DualType
flush(s, output, f=Z_FINISH)
    Compress::Zlib::deflateStream	s
    SV * output 
    int  f
    uInt	cur_length = NO_INIT
    uInt	increment = NO_INIT
  CODE:
  
    s->stream.avail_in = 0; /* should be zero already anyway */
  
    /* retrieve the output buffer */
    output = deRef_l(output, "flush") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(output) && !sv_utf8_downgrade(output, 1))
         croak("Wide character in Compress::Zlib::Deflate::flush input parameter");
#endif         
    if(! s->flags & FLAG_APPEND) {
        SvCUR_set(output, 0);
        /* sv_setpvn(output, "", 0); */
    }
    cur_length =  SvCUR(output) ;
    s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length;
    increment =  SvLEN(output) -  cur_length;
    s->stream.avail_out =  increment;
#ifdef SETP_BYTE
    /* Check for saved output from deflateParams */
    if (s->deflateParams_out_valid) {
	*(s->stream.next_out) = s->deflateParams_out_byte;
	++ s->stream.next_out;
	-- s->stream.avail_out ;
	s->deflateParams_out_valid = FALSE;
    }
#else
    /* Check for saved output from deflateParams */
    if (s->deflateParams_out_length) {
        uLong plen = s->deflateParams_out_length ;
        /* printf("Copy %d bytes saved data\n", plen); */
        if (s->stream.avail_out < plen) {
            /* printf("GROW from %d to %d\n", s->stream.avail_out, 
                        SvLEN(output) + plen - s->stream.avail_out); */
            Sv_Grow(output, SvLEN(output) + plen - s->stream.avail_out) ;
        }
        
        Copy(s->stream.next_out, s->deflateParams_out_buffer, plen, Bytef) ;	
        cur_length = cur_length + plen;
        SvCUR_set(output, cur_length);
	s->stream.next_out += plen ;
	s->stream.avail_out = SvLEN(output) - cur_length ;
	increment = s->stream.avail_out;
	s->deflateParams_out_length = 0;
    }
#endif

    for (;;) {
        if (s->stream.avail_out == 0) {
	    /* consumed all the available output, so extend it */
            s->bufinc *= 2 ;
            Sv_Grow(output, SvLEN(output) + s->bufinc) ;
            cur_length += increment ;
            s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length ;
            increment = s->bufinc ;
            s->stream.avail_out = increment;
        }
        RETVAL = deflate(&(s->stream), f);
    
        /* deflate has finished flushing only when it hasn't used up
         * all the available space in the output buffer: 
         */
        if (s->stream.avail_out != 0 || RETVAL != Z_OK )
            break;
    }
  
    RETVAL =  (RETVAL == Z_STREAM_END ? Z_OK : RETVAL) ;
    s->last_error = RETVAL ;
  
    if (RETVAL == Z_OK) {
        SvPOK_only(output);
        SvCUR_set(output, cur_length + increment - s->stream.avail_out) ;
    }
    OUTPUT:
	RETVAL
	output


DualType
_deflateParams(s, flags, level, strategy, bufsize)
  	Compress::Zlib::deflateStream	s
	int 	flags
	int	level
	int	strategy
    	uLong	bufsize
    CODE:
	/* printf("_deflateParams(Flags %d Level %d Strategy %d Bufsize %d)\n", flags, level, strategy, bufsize); 
	printf("Before -- Level %d, Strategy %d, Bufsize %d\n", s->Level, s->Strategy, s->bufsize); */
	if (flags & 1)
	    s->Level = level ;
	if (flags & 2)
	    s->Strategy = strategy ;
        if (flags & 4) {
            s->bufsize = bufsize; 
            s->bufinc  = bufsize; 
	}
	/* printf("After --  Level %d, Strategy %d, Bufsize %d\n", s->Level, s->Strategy, s->bufsize);*/
#ifdef SETP_BYTE
        s->stream.avail_in = 0; 
        s->stream.next_out = &(s->deflateParams_out_byte) ;
        s->stream.avail_out = 1;
	RETVAL = deflateParams(&(s->stream), s->Level, s->Strategy);
	s->deflateParams_out_valid = 
		(RETVAL == Z_OK && s->stream.avail_out == 0) ;
	/* printf("RETVAL %d, avail out %d, byte %c\n", RETVAL, s->stream.avail_out, s->deflateParams_out_byte); */
#else
	/* printf("Level %d Strategy %d, Prev Len %d\n", 
                s->Level, s->Strategy, s->deflateParams_out_length); */
        s->stream.avail_in = 0; 
        if (s->deflateParams_out_buffer == NULL)
            s->deflateParams_out_buffer = safemalloc(deflateParams_BUFFER_SIZE);
        s->stream.next_out = s->deflateParams_out_buffer ;
        s->stream.avail_out = deflateParams_BUFFER_SIZE;

	RETVAL = deflateParams(&(s->stream), s->Level, s->Strategy);
	s->deflateParams_out_length = deflateParams_BUFFER_SIZE - s->stream.avail_out;
	/* printf("RETVAL %d, length out %d, avail %d\n", 
                    RETVAL, s->deflateParams_out_length, s->stream.avail_out ); */
#endif
    OUTPUT:
	RETVAL


int
get_Level(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->Level ;
    OUTPUT:
	RETVAL

int
get_Strategy(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->Strategy ;
    OUTPUT:
	RETVAL


uLong
get_Bufsize(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->bufsize ;
    OUTPUT:
	RETVAL


int
status(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->last_error ;
    OUTPUT:
	RETVAL

uLong
crc32(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->crc32 ;
    OUTPUT:
	RETVAL

uLong
dict_adler(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->dict_adler ;
    OUTPUT:
	RETVAL

uLong
adler32(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->adler32 ;
    OUTPUT:
	RETVAL

uLong
total_in(s)
        Compress::Zlib::deflateStream   s
    CODE:
        RETVAL = s->stream.total_in ;
    OUTPUT:
	RETVAL

uLong
total_out(s)
        Compress::Zlib::deflateStream   s
    CODE:
        RETVAL = s->stream.total_out ;
    OUTPUT:
	RETVAL

char*
msg(s)
        Compress::Zlib::deflateStream   s
    CODE:
	RETVAL = s->stream.msg;
    OUTPUT:
	RETVAL

int 
deflateTune(s, good_length, max_lazy, nice_length, max_chain)
            Compress::Zlib::deflateStream   s
            int good_length
            int max_lazy
            int nice_length
            int max_chain
    CODE:
#ifndef AT_LEAST_ZLIB_1_2_2_3
        good_length = good_length; max_lazy = max_lazy ; /* Silence -Wall */
        nice_length = nice_length; max_chain = max_chain; /* Silence -Wall */
        croak("deflateTune needs zlib 1.2.2.3 or better");
#else
	RETVAL = deflateTune(&(s->stream), good_length, max_lazy, nice_length, max_chain);
#endif
    OUTPUT:
	RETVAL
    

MODULE = Compress::Zlib PACKAGE = Compress::Zlib::inflateStream

void
DispStream(s, message=NULL)
    Compress::Zlib::inflateStream   s
    char *  message

DualType
inflateReset(s)
    Compress::Zlib::inflateStream   s
  CODE:
      RETVAL = inflateReset(&(s->stream)) ;
      if (RETVAL == Z_OK) {
	  PostInitStream(s, s->flags, s->bufsize, s->WindowBits) ;
      }
    OUTPUT:
      RETVAL

DualType 
inflate (s, buf, output)
    Compress::Zlib::inflateStream	s
    SV *	buf
    SV * 	output 
    uInt	cur_length = NO_INIT
    uInt	prefix_length = NO_INIT
    uInt	increment = NO_INIT
  PREINIT:
#ifdef UTF8_AVAILABLE    
    bool	out_utf8  = FALSE;
#endif    
  CODE:
    /* If the buffer is a reference, dereference it */
    buf = deRef(buf, "inflate") ;

    if (s->flags & FLAG_CONSUME_INPUT && SvREADONLY(buf))
        croak("Compress::Zlib::Inflate::inflate input parameter cannot be read-only when ConsumeInput is specified");
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(buf) && !sv_utf8_downgrade(buf, 1))
         croak("Wide character in Compress::Zlib::Inflate::inflate input parameter");
#endif         
    
    /* initialise the input buffer */
    s->stream.next_in = (Bytef*)SvPVbyte_force(buf, *(STRLEN*)&s->stream.avail_in) ;
	
    /* and retrieve the output buffer */
    output = deRef_l(output, "inflate") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(output))
         out_utf8 = TRUE ;
    if (DO_UTF8(output) && !sv_utf8_downgrade(output, 1))
         croak("Wide character in Compress::Zlib::Inflate::inflate output parameter");
#endif         
    if((s->flags & FLAG_APPEND) != FLAG_APPEND) {
        SvCUR_set(output, 0);
    }
    prefix_length = cur_length =  SvCUR(output) ;
    s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length;
    increment =  SvLEN(output) -  cur_length;
    s->stream.avail_out =  increment;
    s->bytesInflated = 0;
    
    while (1) {

        if (s->stream.avail_out == 0) {
	    /* out of space in the output buffer so make it bigger */
            s->bufinc *= 2 ;
            Sv_Grow(output, SvLEN(output) + s->bufinc + 1) ;
            cur_length += increment ;
            s->stream.next_out = (Bytef*) SvPVbyte_nolen(output) + cur_length ;
            increment = s->bufinc ;
            s->stream.avail_out = increment;
        }

        RETVAL = inflate(&(s->stream), Z_SYNC_FLUSH);


        if (RETVAL == Z_BUF_ERROR) {
            if (s->stream.avail_out == 0)
                continue ;
            if (s->stream.avail_in == 0) {
                RETVAL = Z_OK ;
                break ;
            }
        }
	
        if (RETVAL == Z_NEED_DICT && s->dictionary) {
            s->dict_adler = s->stream.adler ;
            RETVAL = inflateSetDictionary(&(s->stream), 
            (const Bytef*)SvPVbyte_nolen(s->dictionary),
            SvCUR(s->dictionary));
        }

        if (RETVAL != Z_OK) 
            break;
    }

    s->last_error = RETVAL ;
    if (RETVAL == Z_OK || RETVAL == Z_STREAM_END || RETVAL == Z_DATA_ERROR) {
	unsigned in ;

        s->bytesInflated = cur_length + increment - s->stream.avail_out - prefix_length;
        SvPOK_only(output);
        SvCUR_set(output, prefix_length + s->bytesInflated) ;
	*SvEND(output) = '\0';
#ifdef UTF8_AVAILABLE    
        if (out_utf8)
            sv_utf8_upgrade(output);
#endif        

        if (s->flags & FLAG_CRC32 )
            s->crc32 = crc32(s->crc32, 
				(const Bytef*)SvPVbyte_nolen(output)+prefix_length, 
            			SvCUR(output)-prefix_length) ;

        if (s->flags & FLAG_ADLER32) 
            s->adler32 = adler32(s->adler32, 
				(const Bytef*)SvPVbyte_nolen(output)+prefix_length, 
            			SvCUR(output)-prefix_length) ;

	/* fix the input buffer */
	if (s->flags & FLAG_CONSUME_INPUT) {
	    in = s->stream.avail_in ;
	    SvCUR_set(buf, in) ;
	    if (in)
	        Move(s->stream.next_in, SvPVbyte_nolen(buf), in, char) ;	
            *SvEND(buf) = '\0';
            SvSETMAGIC(buf);
	}
    }
    OUTPUT:
	RETVAL
	buf
	output

uLong
inflateCount(s)
    Compress::Zlib::inflateStream	s
    CODE:
        RETVAL = s->bytesInflated;
  OUTPUT:
	RETVAL


DualType 
inflateSync (s, buf)
    Compress::Zlib::inflateStream	s
    SV *	buf
  CODE:
  
    /* If the buffer is a reference, dereference it */
    buf = deRef(buf, "inflateSync") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(buf) && !sv_utf8_downgrade(buf, 1))
         croak("Wide character in Compress::Zlib::Inflate::inflateSync");
#endif         
    
    /* initialise the input buffer */
    s->stream.next_in = (Bytef*)SvPVbyte_nolen(buf) ;
    s->stream.avail_in = SvCUR(buf) ;
	
    /* inflateSync doesn't create any output */
    s->stream.next_out = (Bytef*) NULL;
    s->stream.avail_out = 0;

    RETVAL = inflateSync(&(s->stream));
    s->last_error = RETVAL ;

    /* fix the input buffer */
    {
	unsigned in = s->stream.avail_in ;
 	SvCUR_set(buf, in) ;
 	if (in)
     	    Move(s->stream.next_in, SvPVbyte_nolen(buf), in, char) ;	
        *SvEND(buf) = '\0';
        SvSETMAGIC(buf);
    }
    OUTPUT:
	RETVAL
	buf

void
DESTROY(s)
    Compress::Zlib::inflateStream	s
  CODE:
    inflateEnd(&s->stream) ;
    if (s->dictionary)
	SvREFCNT_dec(s->dictionary) ;
#ifndef SETP_BYTE
    if (s->deflateParams_out_buffer)
        Safefree(s->deflateParams_out_buffer);
#endif
#ifdef MAGIC_APPEND
    if (s->window)
        Safefree(s->window);
#endif
    Safefree(s) ;


uLong
status(s)
        Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->last_error ;
    OUTPUT:
	RETVAL

uLong
crc32(s)
        Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->crc32 ;
    OUTPUT:
	RETVAL

uLong
dict_adler(s)
        Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->dict_adler ;
    OUTPUT:
	RETVAL

uLong
total_in(s)
        Compress::Zlib::inflateStream   s
    CODE:
        RETVAL = s->stream.total_in ;
    OUTPUT:
	RETVAL

uLong
adler32(s)
        Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->adler32 ;
    OUTPUT:
	RETVAL

uLong
total_out(s)
        Compress::Zlib::inflateStream   s
    CODE:
        RETVAL = s->stream.total_out ;
    OUTPUT:
	RETVAL

char*
msg(s)
	Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->stream.msg;
    OUTPUT:
	RETVAL


uLong
get_Bufsize(s)
        Compress::Zlib::inflateStream   s
    CODE:
	RETVAL = s->bufsize ;
    OUTPUT:
	RETVAL

bool
set_Append(s, mode)
        Compress::Zlib::inflateStream   s
	bool	mode
    CODE:
        RETVAL = ((s->flags & FLAG_APPEND) == FLAG_APPEND);
	if (mode)
	    s->flags |= FLAG_APPEND ;
	else
	    s->flags &= ~FLAG_APPEND ;
    OUTPUT:
        RETVAL

MODULE = Compress::Zlib PACKAGE = Compress::Zlib::inflateScanStream

void
DESTROY(s)
    Compress::Zlib::inflateScanStream	s
  CODE:
    inflateEnd(&s->stream) ;
    if (s->dictionary)
	SvREFCNT_dec(s->dictionary) ;
#ifndef SETP_BYTE
    if (s->deflateParams_out_buffer)
        Safefree(s->deflateParams_out_buffer);
#endif
#ifdef MAGIC_APPEND
    if (s->window)
        Safefree(s->window);
#endif
    Safefree(s) ;

void
DispStream(s, message=NULL)
    Compress::Zlib::inflateScanStream   s
    char *  message

DualType 
scan(s, buf, out=NULL)
    Compress::Zlib::inflateScanStream	s
    SV *	buf
    SV *	out
    int    start_len = NO_INIT
  ALIAS:
    inflate = 1
  CODE:
    /* If the input buffer is a reference, dereference it */
    ix = ix ; /* warning suppression */
#ifndef MAGIC_APPEND
        buf = buf;
        croak("scan needs zlib 1.2.1 or better");
#else
    buf = deRef(buf, "inflateScan") ;
#ifdef UTF8_AVAILABLE    
    if (DO_UTF8(buf) && !sv_utf8_downgrade(buf, 1))
        croak("Wide character in Compress::Zlib::InflateScan::scan input parameter");
#endif         
    
    /* initialise the input buffer */
    s->stream.next_in = (Bytef*)SvPVbyte_force(buf, *(STRLEN*)&s->stream.avail_in) ;
    start_len = s->stream.avail_in ;
    s->bytesInflated = 0 ; 
    do
    {
        if (s->stream.avail_in == 0) {
            RETVAL = Z_OK ;
            break ;
        }

        /* set up output to next available section of sliding window */
        s->stream.avail_out = WINDOW_SIZE - s->window_have;
        s->stream.next_out = s->window + s->window_have;

        /* DispStream(s, "before inflate\n"); */

        /* inflate and check for errors */
        RETVAL = inflate(&(s->stream), Z_BLOCK);


        if (start_len > 1)
            s->window_lastByte = *(s->stream.next_in - 1 ) ;

        if (RETVAL == Z_STREAM_ERROR || RETVAL == Z_MEM_ERROR ||
            RETVAL == Z_DATA_ERROR )
            break ;

        if (s->flags & FLAG_CRC32 )
            s->crc32 = crc32(s->crc32, s->window + s->window_have, 
                             WINDOW_SIZE - s->window_have - s->stream.avail_out);

        if (s->flags & FLAG_ADLER32) 
            s->adler32 = adler32(s->adler32, s->window + s->window_have, 
                                 WINDOW_SIZE - s->window_have - s->stream.avail_out);

        s->bytesInflated += WINDOW_SIZE - s->window_have - s->stream.avail_out;

        if (s->stream.avail_out)
            s->window_have = WINDOW_SIZE - s->stream.avail_out;
        else {
            s->window_have = 0;
            s->window_full = 1;
        }

        /* process end of block */
        if (s->stream.data_type & 128) {
            if (s->stream.data_type & 64) {
                s->window_left = s->stream.data_type & 0x1f;
            }
            else {
                s->window_lastbit = s->stream.data_type & 0x1f;
                s->lastBlockOffset = s->stream.total_in;
            }
        }

    } while (RETVAL != Z_STREAM_END);

    s->last_error = RETVAL ;
    s->window_lastoff = s->stream.total_in ;

    if (RETVAL == Z_STREAM_END)
    {
        s->matchedEndBlock = 1 ;

        /* save the location of the end of the compressed data */
        s->window_end = SvCUR(buf) - s->stream.avail_in - 1 ;
        s->window_endOffset = s->stream.total_in ;
        if (s->window_left)
        {
            -- s->window_endOffset ;
        }

        /* if window wrapped, build dictionary from window by rotating */
        if (s->window_full) {
            rotate(s->window, WINDOW_SIZE, s->window_have);
            s->window_have = WINDOW_SIZE;
        }

        /* if (s->flags & FLAG_CONSUME_INPUT) { */
        if (1) {
            unsigned in = s->stream.avail_in ;
            SvCUR_set(buf, in) ;
            if (in)
                Move(s->stream.next_in, SvPVbyte_nolen(buf), in, char) ;	
                *SvEND(buf) = '\0';
                SvSETMAGIC(buf);
        }
    }
#endif
  OUTPUT:
	RETVAL


uLong
getEndOffset(s)
    Compress::Zlib::inflateScanStream	s
    CODE:
#ifndef MAGIC_APPEND
        croak("getEndOffset needs zlib 1.2.1 or better");
#else
        RETVAL = s->window_endOffset;
#endif
  OUTPUT:
	RETVAL

uLong
inflateCount(s)
    Compress::Zlib::inflateScanStream	s
    CODE:
#ifndef MAGIC_APPEND
        croak("inflateCount needs zlib 1.2.1 or better");
#else
        RETVAL = s->bytesInflated;
#endif
  OUTPUT:
	RETVAL


uLong
getLastBlockOffset(s)
    Compress::Zlib::inflateScanStream	s
    CODE:
#ifndef MAGIC_APPEND
        croak("getLastBlockOffset needs zlib 1.2.1 or better");
#else
        RETVAL = s->lastBlockOffset - (s->window_lastbit != 0);
#endif
  OUTPUT:
	RETVAL

uLong
getLastBufferOffset(s)
    Compress::Zlib::inflateScanStream	s
    CODE:
#ifndef MAGIC_APPEND
        croak("getLastBufferOffset needs zlib 1.2.1 or better");
#else
        RETVAL = s->window_lastoff;
#endif
  OUTPUT:
	RETVAL

void
resetLastBlockByte(s, byte)
    Compress::Zlib::inflateScanStream	s
    unsigned char*                      byte
    CODE:
#ifndef MAGIC_APPEND
        croak("resetLastBlockByte needs zlib 1.2.1 or better");
#else
        *byte = *byte ^ (1 << ((8 - s->window_lastbit) & 7));
#endif


void
_createDeflateStream(inf_s, flags,level, method, windowBits, memLevel, strategy, bufsize)
    Compress::Zlib::inflateScanStream	inf_s
    int flags
    int	level
    int method
    int windowBits
    int memLevel
    int strategy
    uLong bufsize
  PPCODE:
  {
#ifndef MAGIC_APPEND
        flags = flags;
        level = level ;
        method = method;
        windowBits = windowBits;
        memLevel = memLevel;
        strategy = strategy;
        bufsize= bufsize;
        croak("_createDeflateStream needs zlib 1.2.1 or better");
#else
    int err ;
    deflateStream s ;

    if (trace)
        warn("in _createDeflateStream(level=%d, method=%d, windowBits=%d, memLevel=%d, strategy=%d, bufsize=%lu\n",
	level, method, windowBits, memLevel, strategy, bufsize) ;
    if ((s = InitStream() )) {

        s->Level      = level;
        s->Method     = method;
        s->WindowBits = windowBits;
        s->MemLevel   = memLevel;
        s->Strategy   = strategy;

        err = deflateInit2(&(s->stream), level, 
			   method, windowBits, memLevel, strategy);

	if (err == Z_OK) {
	    err = deflateSetDictionary(&(s->stream), inf_s->window, inf_s->window_have);
	    s->dict_adler = s->stream.adler ;
	}

        if (err != Z_OK) {
            Safefree(s) ;
            s = NULL ;
	}
	else {
	    PostInitStream(s, flags, bufsize, windowBits) ;
            s->crc32            = inf_s->crc32;
            s->adler32          = inf_s->adler32;
            s->stream.adler     = inf_s->stream.adler ;
            /* s->stream.total_out = inf_s->bytesInflated ; */
            s->stream.total_in  = inf_s->stream.total_out ;
            if (inf_s->window_left) {
                /* printf("** window_left %d, window_lastByte %d\n", inf_s->window_left, inf_s->window_lastByte); */
                deflatePrime(&(s->stream), 8 - inf_s->window_left, inf_s->window_lastByte);
            }
        }
    }
    else
        err = Z_MEM_ERROR ;

    XPUSHs(sv_setref_pv(sv_newmortal(), 
            "Compress::Zlib::deflateStream", (void*)s));
    if (GIMME == G_ARRAY) {
        SV * sv = sv_2mortal(newSViv(err)) ;
        setDUALstatus(sv, err);
        XPUSHs(sv) ;
    }
#endif
  }

DualType
status(s)
        Compress::Zlib::inflateScanStream   s
    CODE:
	RETVAL = s->last_error ;
    OUTPUT:
	RETVAL

uLong
crc32(s)
        Compress::Zlib::inflateScanStream   s
    CODE:
	RETVAL = s->crc32 ;
    OUTPUT:
	RETVAL


uLong
adler32(s)
        Compress::Zlib::inflateScanStream   s
    CODE:
	RETVAL = s->adler32 ;
    OUTPUT:
	RETVAL