unzip.cpp

这是CODEPROJECT上的zip压缩解压代码

  Byte *write;         // window write pointer 
  check_func checkfn;   // check function 
  uLong check;          // check on output 

};


// defines for inflate input/output
//   update pointers and return 
#define UPDBITS {s->bitb=b;s->bitk=k;}
#define UPDIN {z->avail_in=n;z->total_in+=(uLong)(p-z->next_in);z->next_in=p;}
#define UPDOUT {s->write=q;}
#define UPDATE {UPDBITS UPDIN UPDOUT}
#define LEAVE {UPDATE return inflate_flush(s,z,r);}
//   get bytes and bits 
#define LOADIN {p=z->next_in;n=z->avail_in;b=s->bitb;k=s->bitk;}
#define NEEDBYTE {if(n)r=Z_OK;else LEAVE}
#define NEXTBYTE (n--,*p++)
#define NEEDBITS(j) {while(k<(j)){NEEDBYTE;b|=((uLong)NEXTBYTE)<<k;k+=8;}}
#define DUMPBITS(j) {b>>=(j);k-=(j);}
//   output bytes 
#define WAVAIL (uInt)(q<s->read?s->read-q-1:s->end-q)
#define LOADOUT {q=s->write;m=(uInt)WAVAIL;m;}
#define WRAP {if(q==s->end&&s->read!=s->window){q=s->window;m=(uInt)WAVAIL;}}
#define FLUSH {UPDOUT r=inflate_flush(s,z,r); LOADOUT}
#define NEEDOUT {if(m==0){WRAP if(m==0){FLUSH WRAP if(m==0) LEAVE}}r=Z_OK;}
#define OUTBYTE(a) {*q++=(Byte)(a);m--;}
//   load local pointers 
#define LOAD {LOADIN LOADOUT}

// masks for lower bits (size given to avoid silly warnings with Visual C++) 
// And'ing with mask[n] masks the lower n bits
const uInt inflate_mask[17] = {
    0x0000,
    0x0001, 0x0003, 0x0007, 0x000f, 0x001f, 0x003f, 0x007f, 0x00ff,
    0x01ff, 0x03ff, 0x07ff, 0x0fff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};

// copy as much as possible from the sliding window to the output area
int inflate_flush (inflate_blocks_statef *, z_streamp, int);

int inflate_fast (uInt, uInt, const inflate_huft *, const inflate_huft *, inflate_blocks_statef *, z_streamp );



const uInt fixed_bl = 9;
const uInt fixed_bd = 5;
const inflate_huft fixed_tl[] = {
    {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
    {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},192},
    {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},160},
    {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},224},
    {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},144},
    {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},208},
    {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},176},
    {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},240},
    {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
    {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},200},
    {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},168},
    {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},232},
    {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},152},
    {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},216},
    {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},184},
    {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},248},
    {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
    {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},196},
    {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},164},
    {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},228},
    {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},148},
    {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},212},
    {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},180},
    {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},244},
    {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
    {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},204},
    {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},172},
    {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},236},
    {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},156},
    {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},220},
    {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},188},
    {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},252},
    {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
    {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},194},
    {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},162},
    {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},226},
    {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},146},
    {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},210},
    {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},178},
    {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},242},
    {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
    {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},202},
    {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},170},
    {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},234},
    {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},154},
    {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},218},
    {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},186},
    {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},250},
    {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
    {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},198},
    {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},166},
    {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},230},
    {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},150},
    {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},214},
    {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},182},
    {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},246},
    {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
    {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},206},
    {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},174},
    {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},238},
    {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},158},
    {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},222},
    {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},190},
    {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},254},
    {{{96,7}},256}, {{{0,8}},80}, {{{0,8}},16}, {{{84,8}},115},
    {{{82,7}},31}, {{{0,8}},112}, {{{0,8}},48}, {{{0,9}},193},
    {{{80,7}},10}, {{{0,8}},96}, {{{0,8}},32}, {{{0,9}},161},
    {{{0,8}},0}, {{{0,8}},128}, {{{0,8}},64}, {{{0,9}},225},
    {{{80,7}},6}, {{{0,8}},88}, {{{0,8}},24}, {{{0,9}},145},
    {{{83,7}},59}, {{{0,8}},120}, {{{0,8}},56}, {{{0,9}},209},
    {{{81,7}},17}, {{{0,8}},104}, {{{0,8}},40}, {{{0,9}},177},
    {{{0,8}},8}, {{{0,8}},136}, {{{0,8}},72}, {{{0,9}},241},
    {{{80,7}},4}, {{{0,8}},84}, {{{0,8}},20}, {{{85,8}},227},
    {{{83,7}},43}, {{{0,8}},116}, {{{0,8}},52}, {{{0,9}},201},
    {{{81,7}},13}, {{{0,8}},100}, {{{0,8}},36}, {{{0,9}},169},
    {{{0,8}},4}, {{{0,8}},132}, {{{0,8}},68}, {{{0,9}},233},
    {{{80,7}},8}, {{{0,8}},92}, {{{0,8}},28}, {{{0,9}},153},
    {{{84,7}},83}, {{{0,8}},124}, {{{0,8}},60}, {{{0,9}},217},
    {{{82,7}},23}, {{{0,8}},108}, {{{0,8}},44}, {{{0,9}},185},
    {{{0,8}},12}, {{{0,8}},140}, {{{0,8}},76}, {{{0,9}},249},
    {{{80,7}},3}, {{{0,8}},82}, {{{0,8}},18}, {{{85,8}},163},
    {{{83,7}},35}, {{{0,8}},114}, {{{0,8}},50}, {{{0,9}},197},
    {{{81,7}},11}, {{{0,8}},98}, {{{0,8}},34}, {{{0,9}},165},
    {{{0,8}},2}, {{{0,8}},130}, {{{0,8}},66}, {{{0,9}},229},
    {{{80,7}},7}, {{{0,8}},90}, {{{0,8}},26}, {{{0,9}},149},
    {{{84,7}},67}, {{{0,8}},122}, {{{0,8}},58}, {{{0,9}},213},
    {{{82,7}},19}, {{{0,8}},106}, {{{0,8}},42}, {{{0,9}},181},
    {{{0,8}},10}, {{{0,8}},138}, {{{0,8}},74}, {{{0,9}},245},
    {{{80,7}},5}, {{{0,8}},86}, {{{0,8}},22}, {{{192,8}},0},
    {{{83,7}},51}, {{{0,8}},118}, {{{0,8}},54}, {{{0,9}},205},
    {{{81,7}},15}, {{{0,8}},102}, {{{0,8}},38}, {{{0,9}},173},
    {{{0,8}},6}, {{{0,8}},134}, {{{0,8}},70}, {{{0,9}},237},
    {{{80,7}},9}, {{{0,8}},94}, {{{0,8}},30}, {{{0,9}},157},
    {{{84,7}},99}, {{{0,8}},126}, {{{0,8}},62}, {{{0,9}},221},
    {{{82,7}},27}, {{{0,8}},110}, {{{0,8}},46}, {{{0,9}},189},
    {{{0,8}},14}, {{{0,8}},142}, {{{0,8}},78}, {{{0,9}},253},
    {{{96,7}},256}, {{{0,8}},81}, {{{0,8}},17}, {{{85,8}},131},
    {{{82,7}},31}, {{{0,8}},113}, {{{0,8}},49}, {{{0,9}},195},
    {{{80,7}},10}, {{{0,8}},97}, {{{0,8}},33}, {{{0,9}},163},
    {{{0,8}},1}, {{{0,8}},129}, {{{0,8}},65}, {{{0,9}},227},
    {{{80,7}},6}, {{{0,8}},89}, {{{0,8}},25}, {{{0,9}},147},
    {{{83,7}},59}, {{{0,8}},121}, {{{0,8}},57}, {{{0,9}},211},
    {{{81,7}},17}, {{{0,8}},105}, {{{0,8}},41}, {{{0,9}},179},
    {{{0,8}},9}, {{{0,8}},137}, {{{0,8}},73}, {{{0,9}},243},
    {{{80,7}},4}, {{{0,8}},85}, {{{0,8}},21}, {{{80,8}},258},
    {{{83,7}},43}, {{{0,8}},117}, {{{0,8}},53}, {{{0,9}},203},
    {{{81,7}},13}, {{{0,8}},101}, {{{0,8}},37}, {{{0,9}},171},
    {{{0,8}},5}, {{{0,8}},133}, {{{0,8}},69}, {{{0,9}},235},
    {{{80,7}},8}, {{{0,8}},93}, {{{0,8}},29}, {{{0,9}},155},
    {{{84,7}},83}, {{{0,8}},125}, {{{0,8}},61}, {{{0,9}},219},
    {{{82,7}},23}, {{{0,8}},109}, {{{0,8}},45}, {{{0,9}},187},
    {{{0,8}},13}, {{{0,8}},141}, {{{0,8}},77}, {{{0,9}},251},
    {{{80,7}},3}, {{{0,8}},83}, {{{0,8}},19}, {{{85,8}},195},
    {{{83,7}},35}, {{{0,8}},115}, {{{0,8}},51}, {{{0,9}},199},
    {{{81,7}},11}, {{{0,8}},99}, {{{0,8}},35}, {{{0,9}},167},
    {{{0,8}},3}, {{{0,8}},131}, {{{0,8}},67}, {{{0,9}},231},
    {{{80,7}},7}, {{{0,8}},91}, {{{0,8}},27}, {{{0,9}},151},
    {{{84,7}},67}, {{{0,8}},123}, {{{0,8}},59}, {{{0,9}},215},
    {{{82,7}},19}, {{{0,8}},107}, {{{0,8}},43}, {{{0,9}},183},
    {{{0,8}},11}, {{{0,8}},139}, {{{0,8}},75}, {{{0,9}},247},
    {{{80,7}},5}, {{{0,8}},87}, {{{0,8}},23}, {{{192,8}},0},
    {{{83,7}},51}, {{{0,8}},119}, {{{0,8}},55}, {{{0,9}},207},
    {{{81,7}},15}, {{{0,8}},103}, {{{0,8}},39}, {{{0,9}},175},
    {{{0,8}},7}, {{{0,8}},135}, {{{0,8}},71}, {{{0,9}},239},
    {{{80,7}},9}, {{{0,8}},95}, {{{0,8}},31}, {{{0,9}},159},
    {{{84,7}},99}, {{{0,8}},127}, {{{0,8}},63}, {{{0,9}},223},
    {{{82,7}},27}, {{{0,8}},111}, {{{0,8}},47}, {{{0,9}},191},
    {{{0,8}},15}, {{{0,8}},143}, {{{0,8}},79}, {{{0,9}},255}
  };
const inflate_huft fixed_td[] = {
    {{{80,5}},1}, {{{87,5}},257}, {{{83,5}},17}, {{{91,5}},4097},
    {{{81,5}},5}, {{{89,5}},1025}, {{{85,5}},65}, {{{93,5}},16385},
    {{{80,5}},3}, {{{88,5}},513}, {{{84,5}},33}, {{{92,5}},8193},
    {{{82,5}},9}, {{{90,5}},2049}, {{{86,5}},129}, {{{192,5}},24577},
    {{{80,5}},2}, {{{87,5}},385}, {{{83,5}},25}, {{{91,5}},6145},
    {{{81,5}},7}, {{{89,5}},1537}, {{{85,5}},97}, {{{93,5}},24577},
    {{{80,5}},4}, {{{88,5}},769}, {{{84,5}},49}, {{{92,5}},12289},
    {{{82,5}},13}, {{{90,5}},3073}, {{{86,5}},193}, {{{192,5}},24577}
  };







// copy as much as possible from the sliding window to the output area
int inflate_flush(inflate_blocks_statef *s,z_streamp z,int r)
{
  uInt n;
  Byte *p;
  Byte *q;

  // local copies of source and destination pointers 
  p = z->next_out;
  q = s->read;

  // compute number of bytes to copy as far as end of window 
  n = (uInt)((q <= s->write ? s->write : s->end) - q);
  if (n > z->avail_out) n = z->avail_out;
  if (n && r == Z_BUF_ERROR) r = Z_OK;

  // update counters
  z->avail_out -= n;
  z->total_out += n;

  // update check information 
  if (s->checkfn != Z_NULL)
    z->adler = s->check = (*s->checkfn)(s->check, q, n);

  // copy as far as end of window 
  if (n!=0)          // check for n!=0 to avoid waking up CodeGuard
  { memcpy(p, q, n);
    p += n;
    q += n;
  }

  // see if more to copy at beginning of window
  if (q == s->end)
  {
    // wrap pointers 
    q = s->window;
    if (s->write == s->end)
      s->write = s->window;

    // compute bytes to copy 
    n = (uInt)(s->write - q);
    if (n > z->avail_out) n = z->avail_out;
    if (n && r == Z_BUF_ERROR) r = Z_OK;

    // update counters 
    z->avail_out -= n;
    z->total_out += n;

    // update check information 
    if (s->checkfn != Z_NULL)
      z->adler = s->check = (*s->checkfn)(s->check, q, n);

    // copy
    if (n!=0) {memcpy(p,q,n); p+=n; q+=n;}
  }

  // update pointers
  z->next_out = p;
  s->read = q;

  // done
  return r;
}






// simplify the use of the inflate_huft type with some defines
#define exop word.what.Exop
#define bits word.what.Bits

typedef enum {        // waiting for "i:"=input, "o:"=output, "x:"=nothing 
      START,    // x: set up for LEN 
      LEN,      // i: get length/literal/eob next 
      LENEXT,   // i: getting length extra (have base) 
      DIST,     // i: get distance next 
      DISTEXT,  // i: getting distance extra 
      COPY,     // o: copying bytes in window, waiting for space
      LIT,      // o: got literal, waiting for output space 
      WASH,     // o: got eob, possibly still output waiting 
      END,      // x: got eob and all data flushed 
      BADCODE}  // x: got error 
inflate_codes_mode;

// inflate codes private state
struct inflate_codes_state {

  // mode 
  inflate_codes_mode mode;      // current inflate_codes mode 

  // mode dependent information 
  uInt len;
  union {
    struct {
      const inflate_huft *tree;       // pointer into tree 
      uInt need;                // bits needed 
    } code;             // if LEN or DIST, where in tree 
    uInt lit;           // if LIT, literal 
    struct {
      uInt get;                 // bits to get for extra 
      uInt dist;                // distance back to copy from 
    } copy;             // if EXT or COPY, where and how much 
  } sub;                // submode

  // mode independent information 
  Byte lbits;           // ltree bits decoded per branch 
  Byte dbits;           // dtree bits decoder per branch 
  const inflate_huft *ltree;          // literal/length/eob tree
  const inflate_huft *dtree;          // distance tree

};


inflate_codes_statef *inflate_codes_new(
uInt bl, uInt bd,
const inflate_huft *tl,
const inflate_huft *td, // need separate declaration for Borland C++
z_streamp z)
{
  inflate_codes_statef *c;

  if ((c = (inflate_codes_statef *)
       ZALLOC(z,1,sizeof(struct inflate_codes_state))) != Z_NULL)
  {
    c->mode = START;
    c->lbits = (Byte)bl;
    c->dbits = (Byte)bd;
    c->ltree = tl;
    c->dtree = td;
    LuTracev((stderr, "inflate:       codes new\n"));
  }
  return c;
}


int inflate_codes(inflate_blocks_statef *s, z_streamp z, int r)
{
  uInt j;               // temporary storage
  const inflate_huft *t;      // temporary pointer
  uInt e;               // extra bits or operation
  uLong b;              // bit buffer
  uInt k;               // bits in bit buffer
  Byte *p;             // input data pointer
  uInt n;               // bytes available there
  Byte *q;             // output window write pointer
  uInt m;               // bytes to end of window or read pointer
  Byte *f;             // pointer to copy strings from
  inflate_codes_statef *c = s->sub.decode.codes;  // codes state

  // copy input/output information to locals (UPDATE macro restores)
  LOAD