Exemplo n.º 1
0
        internal int Initialize(ZCodec codec, int w)
        {
            _codec         = codec;
            _codec.Message = null;
            blocks         = null;

            // handle undocumented nowrap option (no zlib header or check)
            //nowrap = 0;
            //if (w < 0)
            //{
            //    w = - w;
            //    nowrap = 1;
            //}

            // set window size
            if (w < 8 || w > 15)
            {
                End();
                throw new IOException("Bad window size.");

                //return ZConstants.Z_STREAM_ERROR;
            }
            wbits = w;

            blocks = new InflateBlocks(codec,
                                       HandleRfc1950HeaderBytes ? this : null,
                                       1 << w);

            // reset state
            Reset();
            return(ZConstants.Z_OK);
        }
Exemplo n.º 2
0
 // Methods
 internal InflateBlocks(ZCodec codec, System.Object checkfn, int w)
 {
     _codec       = codec;
     hufts        = new int[MANY * 3];
     window       = new byte[w];
     end          = w;
     this.checkfn = checkfn;
     mode         = InflateBlockMode.TYPE;
     Reset();
 }
Exemplo n.º 3
0
 private void end()
 {
     if (z == null)
     {
         return;
     }
     if (_wantCompress)
     {
         _z.EndDeflate();
     }
     else
     {
         _z.EndInflate();
     }
     _z = null;
 }
Exemplo n.º 4
0
        internal int inflate_trees_bits(int[] c, int[] bb, int[] tb, int[] hp, ZCodec z)
        {
            int result;

            initWorkArea(19);
            hn[0]  = 0;
            result = huft_build(c, 0, 19, 19, null, null, tb, bb, hp, hn, v);

            if (result == Z_DATA_ERROR)
            {
                z.Message = "oversubscribed dynamic bit lengths tree";
            }
            else if (result == Z_BUF_ERROR || bb[0] == 0)
            {
                z.Message = "incomplete dynamic bit lengths tree";
                result    = Z_DATA_ERROR;
            }
            return(result);
        }
Exemplo n.º 5
0
 internal static int inflate_trees_fixed(int[] bl, int[] bd, int[][] tl, int[][] td, ZCodec z)
 {
     bl[0] = fixed_bl;
     bd[0] = fixed_bd;
     tl[0] = fixed_tl;
     td[0] = fixed_td;
     return(Z_OK);
 }
Exemplo n.º 6
0
        internal int inflate_trees_dynamic(int nl, int nd, int[] c, int[] bl, int[] bd, int[] tl, int[] td, int[] hp, ZCodec z)
        {
            int result;

            // build literal/length tree
            initWorkArea(288);
            hn[0]  = 0;
            result = huft_build(c, 0, nl, 257, cplens, cplext, tl, bl, hp, hn, v);
            if (result != Z_OK || bl[0] == 0)
            {
                if (result == Z_DATA_ERROR)
                {
                    z.Message = "oversubscribed literal/length tree";
                }
                else if (result != Z_MEM_ERROR)
                {
                    z.Message = "incomplete literal/length tree";
                    result    = Z_DATA_ERROR;
                }
                return(result);
            }

            // build distance tree
            initWorkArea(288);
            result = huft_build(c, nl, nd, 0, cpdist, cpdext, td, bd, hp, hn, v);

            if (result != Z_OK || (bd[0] == 0 && nl > 257))
            {
                if (result == Z_DATA_ERROR)
                {
                    z.Message = "oversubscribed distance tree";
                }
                else if (result == Z_BUF_ERROR)
                {
                    z.Message = "incomplete distance tree";
                    result    = Z_DATA_ERROR;
                }
                else if (result != Z_MEM_ERROR)
                {
                    z.Message = "empty distance tree with lengths";
                    result    = Z_DATA_ERROR;
                }
                return(result);
            }

            return(Z_OK);
        }
Exemplo n.º 7
0
        // Called with number of bytes left to write in window at least 258
        // (the maximum string length) and number of input bytes available
        // at least ten.  The ten bytes are six bytes for the longest length/
        // distance pair plus four bytes for overloading the bit buffer.
        internal int InflateFast(int bl, int bd, int[] tl, int tl_index, int[] td, int td_index, InflateBlocks s, ZCodec z)
        {
            int t;            // temporary pointer

            int[] tp;         // temporary pointer
            int   tp_index;   // temporary pointer
            int   e;          // extra bits or operation
            int   b;          // bit buffer
            int   k;          // bits in bit buffer
            int   p;          // input data pointer
            int   n;          // bytes available there
            int   q;          // output window write pointer
            int   m;          // bytes to end of window or read pointer
            int   ml;         // mask for literal/length tree
            int   md;         // mask for distance tree
            int   c;          // bytes to copy
            int   d;          // distance back to copy from
            int   r;          // copy source pointer

            int tp_index_t_3; // (tp_index+t)*3

            // load input, output, bit values
            p = z.NextIn; n = z.AvailableBytesIn; b = s.bitb; k = s.bitk;
            q = s.writeAt; m = q < s.readAt ? s.readAt - q - 1 : s.end - q;

            // initialize masks
            ml = InternalInflateConstants.InflateMask[bl];
            md = InternalInflateConstants.InflateMask[bd];

            // do until not enough input or output space for fast loop
            do
            {
                // assume called with m >= 258 && n >= 10
                // get literal/length code
                while (k < (20))
                {
                    // max bits for literal/length code
                    n--;
                    b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
                }

                t            = b & ml;
                tp           = tl;
                tp_index     = tl_index;
                tp_index_t_3 = (tp_index + t) * 3;
                if ((e = tp[tp_index_t_3]) == 0)
                {
                    b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);

                    s.window[q++] = (byte)tp[tp_index_t_3 + 2];
                    m--;
                    continue;
                }
                do
                {
                    b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);

                    if ((e & 16) != 0)
                    {
                        e &= 15;
                        c  = tp[tp_index_t_3 + 2] + ((int)b & InternalInflateConstants.InflateMask[e]);

                        b >>= e; k -= e;

                        // decode distance base of block to copy
                        while (k < 15)
                        {
                            // max bits for distance code
                            n--;
                            b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
                        }

                        t            = b & md;
                        tp           = td;
                        tp_index     = td_index;
                        tp_index_t_3 = (tp_index + t) * 3;
                        e            = tp[tp_index_t_3];

                        do
                        {
                            b >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);

                            if ((e & 16) != 0)
                            {
                                // get extra bits to add to distance base
                                e &= 15;
                                while (k < e)
                                {
                                    // get extra bits (up to 13)
                                    n--;
                                    b |= (z.InputBuffer[p++] & 0xff) << k; k += 8;
                                }

                                d = tp[tp_index_t_3 + 2] + (b & InternalInflateConstants.InflateMask[e]);

                                b >>= e; k -= e;

                                // do the copy
                                m -= c;
                                if (q >= d)
                                {
                                    // offset before dest
                                    //  just copy
                                    r = q - d;
                                    if (q - r > 0 && 2 > (q - r))
                                    {
                                        s.window[q++] = s.window[r++]; // minimum count is three,
                                        s.window[q++] = s.window[r++]; // so unroll loop a little
                                        c            -= 2;
                                    }
                                    else
                                    {
                                        Array.Copy(s.window, r, s.window, q, 2);
                                        q += 2; r += 2; c -= 2;
                                    }
                                }
                                else
                                {
                                    // else offset after destination
                                    r = q - d;
                                    do
                                    {
                                        r += s.end; // force pointer in window
                                    }while (r < 0); // covers invalid distances
                                    e = s.end - r;
                                    if (c > e)
                                    {
                                        // if source crosses,
                                        c -= e; // wrapped copy
                                        if (q - r > 0 && e > (q - r))
                                        {
                                            do
                                            {
                                                s.window[q++] = s.window[r++];
                                            }while (--e != 0);
                                        }
                                        else
                                        {
                                            Array.Copy(s.window, r, s.window, q, e);
                                            q += e; r += e; e = 0;
                                        }
                                        r = 0; // copy rest from start of window
                                    }
                                }

                                // copy all or what's left
                                if (q - r > 0 && c > (q - r))
                                {
                                    do
                                    {
                                        s.window[q++] = s.window[r++];
                                    }while (--c != 0);
                                }
                                else
                                {
                                    Array.Copy(s.window, r, s.window, q, c);
                                    q += c; r += c; c = 0;
                                }
                                break;
                            }
                            else if ((e & 64) == 0)
                            {
                                t           += tp[tp_index_t_3 + 2];
                                t           += (b & InternalInflateConstants.InflateMask[e]);
                                tp_index_t_3 = (tp_index + t) * 3;
                                e            = tp[tp_index_t_3];
                            }
                            else
                            {
                                z.Message = "invalid distance code";

                                c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);

                                s.bitb             = b; s.bitk = k;
                                z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                                s.writeAt          = q;

                                return(ZConstants.Z_DATA_ERROR);
                            }
                        }while (true);
                        break;
                    }

                    if ((e & 64) == 0)
                    {
                        t           += tp[tp_index_t_3 + 2];
                        t           += (b & InternalInflateConstants.InflateMask[e]);
                        tp_index_t_3 = (tp_index + t) * 3;
                        if ((e = tp[tp_index_t_3]) == 0)
                        {
                            b           >>= (tp[tp_index_t_3 + 1]); k -= (tp[tp_index_t_3 + 1]);
                            s.window[q++] = (byte)tp[tp_index_t_3 + 2];
                            m--;
                            break;
                        }
                    }
                    else if ((e & 32) != 0)
                    {
                        c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);

                        s.bitb             = b; s.bitk = k;
                        z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                        s.writeAt          = q;

                        return(ZConstants.Z_STREAM_END);
                    }
                    else
                    {
                        z.Message = "invalid literal/length code";

                        c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);

                        s.bitb             = b; s.bitk = k;
                        z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                        s.writeAt          = q;

                        return(ZConstants.Z_DATA_ERROR);
                    }
                }while (true);
            }while (m >= 258 && n >= 10);

            // not enough input or output--restore pointers and return
            c = z.AvailableBytesIn - n; c = (k >> 3) < c ? k >> 3 : c; n += c; p -= c; k -= (c << 3);

            s.bitb             = b; s.bitk = k;
            z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
            s.writeAt          = q;

            return(ZConstants.Z_OK);
        }
Exemplo n.º 8
0
        internal int Process(InflateBlocks blocks, int r)
        {
            int j;      // temporary storage
            int tindex; // temporary pointer
            int e;      // extra bits or operation
            int b = 0;  // bit buffer
            int k = 0;  // bits in bit buffer
            int p = 0;  // input data pointer
            int n;      // bytes available there
            int q;      // output window write pointer
            int m;      // bytes to end of window or read pointer
            int f;      // pointer to copy strings from

            ZCodec z = blocks._codec;

            // copy input/output information to locals (UPDATE macro restores)
            p = z.NextIn;
            n = z.AvailableBytesIn;
            b = blocks.bitb;
            k = blocks.bitk;
            q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;

            // process input and output based on current state
            while (true)
            {
                switch (mode)
                {
                // waiting for "i:"=input, "o:"=output, "x:"=nothing
                case START:      // x: set up for LEN
                    if (m >= 258 && n >= 10)
                    {
                        blocks.bitb        = b; blocks.bitk = k;
                        z.AvailableBytesIn = n;
                        z.TotalBytesIn    += p - z.NextIn;
                        z.NextIn           = p;
                        blocks.writeAt     = q;
                        r = InflateFast(lbits, dbits, ltree, ltree_index, dtree, dtree_index, blocks, z);

                        p = z.NextIn;
                        n = z.AvailableBytesIn;
                        b = blocks.bitb;
                        k = blocks.bitk;
                        q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;

                        if (r != ZConstants.Z_OK)
                        {
                            mode = (r == ZConstants.Z_STREAM_END) ? WASH : BADCODE;
                            break;
                        }
                    }
                    need       = lbits;
                    tree       = ltree;
                    tree_index = ltree_index;

                    mode = LEN;
                    goto case LEN;

                case LEN:      // i: get length/literal/eob next
                    j = need;

                    while (k < j)
                    {
                        if (n != 0)
                        {
                            r = ZConstants.Z_OK;
                        }
                        else
                        {
                            blocks.bitb        = b; blocks.bitk = k;
                            z.AvailableBytesIn = n;
                            z.TotalBytesIn    += p - z.NextIn;
                            z.NextIn           = p;
                            blocks.writeAt     = q;
                            return(blocks.Flush(r));
                        }
                        n--;
                        b |= (z.InputBuffer[p++] & 0xff) << k;
                        k += 8;
                    }

                    tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3;

                    b >>= (tree[tindex + 1]);
                    k  -= (tree[tindex + 1]);

                    e = tree[tindex];

                    if (e == 0)
                    {
                        // literal
                        lit  = tree[tindex + 2];
                        mode = LIT;
                        break;
                    }
                    if ((e & 16) != 0)
                    {
                        // length
                        bitsToGet = e & 15;
                        len       = tree[tindex + 2];
                        mode      = LENEXT;
                        break;
                    }
                    if ((e & 64) == 0)
                    {
                        // next table
                        need       = e;
                        tree_index = tindex / 3 + tree[tindex + 2];
                        break;
                    }
                    if ((e & 32) != 0)
                    {
                        // end of block
                        mode = WASH;
                        break;
                    }
                    mode      = BADCODE; // invalid code
                    z.Message = "invalid literal/length code";
                    r         = ZConstants.Z_DATA_ERROR;

                    blocks.bitb        = b; blocks.bitk = k;
                    z.AvailableBytesIn = n;
                    z.TotalBytesIn    += p - z.NextIn;
                    z.NextIn           = p;
                    blocks.writeAt     = q;
                    return(blocks.Flush(r));


                case LENEXT:      // i: getting length extra (have base)
                    j = bitsToGet;

                    while (k < j)
                    {
                        if (n != 0)
                        {
                            r = ZConstants.Z_OK;
                        }
                        else
                        {
                            blocks.bitb        = b; blocks.bitk = k;
                            z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                            blocks.writeAt     = q;
                            return(blocks.Flush(r));
                        }
                        n--; b |= (z.InputBuffer[p++] & 0xff) << k;
                        k      += 8;
                    }

                    len += (b & InternalInflateConstants.InflateMask[j]);

                    b >>= j;
                    k  -= j;

                    need       = dbits;
                    tree       = dtree;
                    tree_index = dtree_index;
                    mode       = DIST;
                    goto case DIST;

                case DIST:      // i: get distance next
                    j = need;

                    while (k < j)
                    {
                        if (n != 0)
                        {
                            r = ZConstants.Z_OK;
                        }
                        else
                        {
                            blocks.bitb        = b; blocks.bitk = k;
                            z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                            blocks.writeAt     = q;
                            return(blocks.Flush(r));
                        }
                        n--; b |= (z.InputBuffer[p++] & 0xff) << k;
                        k      += 8;
                    }

                    tindex = (tree_index + (b & InternalInflateConstants.InflateMask[j])) * 3;

                    b >>= tree[tindex + 1];
                    k  -= tree[tindex + 1];

                    e = (tree[tindex]);
                    if ((e & 0x10) != 0)
                    {
                        // distance
                        bitsToGet = e & 15;
                        dist      = tree[tindex + 2];
                        mode      = DISTEXT;
                        break;
                    }
                    if ((e & 64) == 0)
                    {
                        // next table
                        need       = e;
                        tree_index = tindex / 3 + tree[tindex + 2];
                        break;
                    }
                    mode      = BADCODE; // invalid code
                    z.Message = "invalid distance code";
                    r         = ZConstants.Z_DATA_ERROR;

                    blocks.bitb        = b; blocks.bitk = k;
                    z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                    blocks.writeAt     = q;
                    return(blocks.Flush(r));


                case DISTEXT:      // i: getting distance extra
                    j = bitsToGet;

                    while (k < j)
                    {
                        if (n != 0)
                        {
                            r = ZConstants.Z_OK;
                        }
                        else
                        {
                            blocks.bitb        = b; blocks.bitk = k;
                            z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                            blocks.writeAt     = q;
                            return(blocks.Flush(r));
                        }
                        n--; b |= (z.InputBuffer[p++] & 0xff) << k;
                        k      += 8;
                    }

                    dist += (b & InternalInflateConstants.InflateMask[j]);

                    b >>= j;
                    k  -= j;

                    mode = COPY;
                    goto case COPY;

                case COPY:      // o: copying bytes in window, waiting for space
                    f = q - dist;
                    while (f < 0)
                    {
                        // modulo window size-"while" instead
                        f += blocks.end;     // of "if" handles invalid distances
                    }
                    while (len != 0)
                    {
                        if (m == 0)
                        {
                            if (q == blocks.end && blocks.readAt != 0)
                            {
                                q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
                            }
                            if (m == 0)
                            {
                                blocks.writeAt = q; r = blocks.Flush(r);
                                q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;

                                if (q == blocks.end && blocks.readAt != 0)
                                {
                                    q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
                                }

                                if (m == 0)
                                {
                                    blocks.bitb        = b; blocks.bitk = k;
                                    z.AvailableBytesIn = n;
                                    z.TotalBytesIn    += p - z.NextIn;
                                    z.NextIn           = p;
                                    blocks.writeAt     = q;
                                    return(blocks.Flush(r));
                                }
                            }
                        }

                        blocks.window[q++] = blocks.window[f++]; m--;

                        if (f == blocks.end)
                        {
                            f = 0;
                        }
                        len--;
                    }
                    mode = START;
                    break;

                case LIT:      // o: got literal, waiting for output space
                    if (m == 0)
                    {
                        if (q == blocks.end && blocks.readAt != 0)
                        {
                            q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
                        }
                        if (m == 0)
                        {
                            blocks.writeAt = q; r = blocks.Flush(r);
                            q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;

                            if (q == blocks.end && blocks.readAt != 0)
                            {
                                q = 0; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;
                            }
                            if (m == 0)
                            {
                                blocks.bitb        = b; blocks.bitk = k;
                                z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                                blocks.writeAt     = q;
                                return(blocks.Flush(r));
                            }
                        }
                    }
                    r = ZConstants.Z_OK;

                    blocks.window[q++] = (byte)lit; m--;

                    mode = START;
                    break;

                case WASH:      // o: got eob, possibly more output
                    if (k > 7)
                    {
                        // return unused byte, if any
                        k -= 8;
                        n++;
                        p--;     // can always return one
                    }

                    blocks.writeAt = q; r = blocks.Flush(r);
                    q = blocks.writeAt; m = q < blocks.readAt ? blocks.readAt - q - 1 : blocks.end - q;

                    if (blocks.readAt != blocks.writeAt)
                    {
                        blocks.bitb        = b; blocks.bitk = k;
                        z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                        blocks.writeAt     = q;
                        return(blocks.Flush(r));
                    }
                    mode = END;
                    goto case END;

                case END:
                    r                  = ZConstants.Z_STREAM_END;
                    blocks.bitb        = b; blocks.bitk = k;
                    z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                    blocks.writeAt     = q;
                    return(blocks.Flush(r));

                case BADCODE:      // x: got error

                    r = ZConstants.Z_DATA_ERROR;

                    blocks.bitb        = b; blocks.bitk = k;
                    z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                    blocks.writeAt     = q;
                    return(blocks.Flush(r));

                default:
                    r = ZConstants.Z_STREAM_ERROR;

                    blocks.bitb        = b; blocks.bitk = k;
                    z.AvailableBytesIn = n; z.TotalBytesIn += p - z.NextIn; z.NextIn = p;
                    blocks.writeAt     = q;
                    return(blocks.Flush(r));
                }
            }
        }
Exemplo n.º 9
0
 // Returns true if inflate is currently at the end of a block generated
 // by Z_SYNC_FLUSH or Z_FULL_FLUSH. This function is used by one PPP
 // implementation to provide an additional safety check. PPP uses Z_SYNC_FLUSH
 // but removes the length bytes of the resulting empty stored block. When
 // decompressing, PPP checks that at the end of input packet, inflate is
 // waiting for these length bytes.
 internal int SyncPoint(ZCodec z)
 {
     return(blocks.SyncPoint());
 }