示例#1
0
        /// <param name="r">
        /// </param><returns></returns>
        internal int Process(int r)
        {
            // copy input/output information to locals (UPDATE macro restores)
            int p = this.Codec.NextIn;
            int n = this.Codec.AvailableBytesIn;
            int b = this.Bitb;
            int k = this.Bitk;

            int q = this.WriteAt;
            int m = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;

            // process input based on current state
            while (true)
            {
                int t; // temporary storage
                switch (this.mode)
                {
                case InflateBlockMode.Type:

                    while (k < 3)
                    {
                        if (n != 0)
                        {
                            r = ZlibConstants.Zok;
                        }
                        else
                        {
                            this.Bitb = b;
                            this.Bitk = k;
                            this.Codec.AvailableBytesIn = n;
                            this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                            this.Codec.NextIn           = p;
                            this.WriteAt = q;
                            return(this.Flush(r));
                        }

                        n--;
                        b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                        k += 8;
                    }

                    t         = b & 7;
                    this.last = t & 1;

                    switch ((uint)t >> 1)
                    {
                    case 0:         // stored
                        b       >>= 3;
                        k        -= 3;
                        t         = k & 7; // go to byte boundary
                        b       >>= t;
                        k        -= t;
                        this.mode = InflateBlockMode.Lens;         // get length of stored block
                        break;

                    case 1:         // fixed
                        var bl = new int[1];
                        var bd = new int[1];
                        var tl = new int[1][];
                        var td = new int[1][];
                        InfTree.InflateTreesFixed(bl, bd, tl, td);
                        this.codes.Init(bl[0], bd[0], tl[0], 0, td[0], 0);
                        b       >>= 3;
                        k        -= 3;
                        this.mode = InflateBlockMode.Codes;
                        break;

                    case 2:         // dynamic
                        b       >>= 3;
                        k        -= 3;
                        this.mode = InflateBlockMode.Table;
                        break;

                    case 3:         // illegal
                        b                         >>= 3;
                        k                          -= 3;
                        this.mode                   = InflateBlockMode.Bad;
                        this.Codec.Message          = "invalid block type";
                        r                           = ZlibConstants.ZDataError;
                        this.Bitb                   = b;
                        this.Bitk                   = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt                = q;
                        return(this.Flush(r));
                    }

                    break;

                case InflateBlockMode.Lens:

                    while (k < 32)
                    {
                        if (n != 0)
                        {
                            r = ZlibConstants.Zok;
                        }
                        else
                        {
                            this.Bitb = b;
                            this.Bitk = k;
                            this.Codec.AvailableBytesIn = n;
                            this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                            this.Codec.NextIn           = p;
                            this.WriteAt = q;
                            return(this.Flush(r));
                        }

                        n--;
                        b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                        k += 8;
                    }

                    if ((((~b) >> 16) & 0xffff) != (b & 0xffff))
                    {
                        this.mode          = InflateBlockMode.Bad;
                        this.Codec.Message = "invalid stored block lengths";
                        r = ZlibConstants.ZDataError;

                        this.Bitb = b;
                        this.Bitk = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt = q;
                        return(this.Flush(r));
                    }

                    this.left = b & 0xffff;
                    b         = k = 0; // dump bits
                    this.mode = this.left != 0
                                        ? InflateBlockMode.Stored
                                        : (this.last != 0 ? InflateBlockMode.Dry : InflateBlockMode.Type);
                    break;

                case InflateBlockMode.Stored:
                    if (n == 0)
                    {
                        this.Bitb = b;
                        this.Bitk = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt = q;
                        return(this.Flush(r));
                    }

                    if (m == 0)
                    {
                        if (q == this.End && this.ReadAt != 0)
                        {
                            q = 0;
                            m = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;
                        }

                        if (m == 0)
                        {
                            this.WriteAt = q;
                            r            = this.Flush(r);
                            q            = this.WriteAt;
                            m            = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;
                            if (q == this.End && this.ReadAt != 0)
                            {
                                q = 0;
                                m = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;
                            }

                            if (m == 0)
                            {
                                this.Bitb = b;
                                this.Bitk = k;
                                this.Codec.AvailableBytesIn = n;
                                this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                                this.Codec.NextIn           = p;
                                this.WriteAt = q;
                                return(this.Flush(r));
                            }
                        }
                    }

                    r = ZlibConstants.Zok;

                    t = this.left;
                    if (t > n)
                    {
                        t = n;
                    }

                    if (t > m)
                    {
                        t = m;
                    }

                    Array.Copy(this.Codec.InputBuffer, p, this.Window, q, t);
                    p += t;
                    n -= t;
                    q += t;
                    m -= t;
                    if ((this.left -= t) != 0)
                    {
                        break;
                    }

                    this.mode = this.last != 0 ? InflateBlockMode.Dry : InflateBlockMode.Type;
                    break;

                case InflateBlockMode.Table:

                    while (k < 14)
                    {
                        if (n != 0)
                        {
                            r = ZlibConstants.Zok;
                        }
                        else
                        {
                            this.Bitb = b;
                            this.Bitk = k;
                            this.Codec.AvailableBytesIn = n;
                            this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                            this.Codec.NextIn           = p;
                            this.WriteAt = q;
                            return(this.Flush(r));
                        }

                        n--;
                        b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                        k += 8;
                    }

                    this.table = t = b & 0x3fff;
                    if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
                    {
                        this.mode          = InflateBlockMode.Bad;
                        this.Codec.Message = "too many length or distance symbols";
                        r = ZlibConstants.ZDataError;

                        this.Bitb = b;
                        this.Bitk = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt = q;
                        return(this.Flush(r));
                    }

                    t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
                    if (this.blens == null || this.blens.Length < t)
                    {
                        this.blens = new int[t];
                    }
                    else
                    {
                        Array.Clear(this.blens, 0, t);

                        // for (int i = 0; i < t; i++) { blens[i] = 0; }
                    }

                    b >>= 14;
                    k  -= 14;

                    this.index = 0;
                    this.mode  = InflateBlockMode.Btree;
                    goto case InflateBlockMode.Btree;

                case InflateBlockMode.Btree:
                    while (this.index < 4 + (this.table >> 10))
                    {
                        while (k < 3)
                        {
                            if (n != 0)
                            {
                                r = ZlibConstants.Zok;
                            }
                            else
                            {
                                this.Bitb = b;
                                this.Bitk = k;
                                this.Codec.AvailableBytesIn = n;
                                this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                                this.Codec.NextIn           = p;
                                this.WriteAt = q;
                                return(this.Flush(r));
                            }

                            n--;
                            b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                            k += 8;
                        }

                        this.blens[Border[this.index++]] = b & 7;

                        b >>= 3;
                        k  -= 3;
                    }

                    while (this.index < 19)
                    {
                        this.blens[Border[this.index++]] = 0;
                    }

                    this.bb[0] = 7;
                    t          = this.inftree.InflateTreesBits(this.blens, this.bb, this.tb, this.hufts, this.Codec);
                    if (t != ZlibConstants.Zok)
                    {
                        r = t;
                        if (r == ZlibConstants.ZDataError)
                        {
                            this.blens = null;
                            this.mode  = InflateBlockMode.Bad;
                        }

                        this.Bitb = b;
                        this.Bitk = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt = q;
                        return(this.Flush(r));
                    }

                    this.index = 0;
                    this.mode  = InflateBlockMode.Dtree;
                    goto case InflateBlockMode.Dtree;

                case InflateBlockMode.Dtree:
                    while (true)
                    {
                        t = this.table;
                        if (!(this.index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)))
                        {
                            break;
                        }

                        t = this.bb[0];

                        while (k < t)
                        {
                            if (n != 0)
                            {
                                r = ZlibConstants.Zok;
                            }
                            else
                            {
                                this.Bitb = b;
                                this.Bitk = k;
                                this.Codec.AvailableBytesIn = n;
                                this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                                this.Codec.NextIn           = p;
                                this.WriteAt = q;
                                return(this.Flush(r));
                            }

                            n--;
                            b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                            k += 8;
                        }

                        t = this.hufts[(this.tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 1];
                        int c = this.hufts[(this.tb[0] + (b & InternalInflateConstants.InflateMask[t])) * 3 + 2];

                        if (c < 16)
                        {
                            b >>= t;
                            k  -= t;
                            this.blens[this.index++] = c;
                        }
                        else
                        {
                            // c == 16..18
                            int i = c == 18 ? 7 : c - 14;
                            int j = c == 18 ? 11 : 3;

                            while (k < (t + i))
                            {
                                if (n != 0)
                                {
                                    r = ZlibConstants.Zok;
                                }
                                else
                                {
                                    this.Bitb = b;
                                    this.Bitk = k;
                                    this.Codec.AvailableBytesIn = n;
                                    this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                                    this.Codec.NextIn           = p;
                                    this.WriteAt = q;
                                    return(this.Flush(r));
                                }

                                n--;
                                b |= (this.Codec.InputBuffer[p++] & 0xff) << k;
                                k += 8;
                            }

                            b >>= t;
                            k  -= t;

                            j += b & InternalInflateConstants.InflateMask[i];

                            b >>= i;
                            k  -= i;

                            i = this.index;
                            t = this.table;
                            if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || (c == 16 && i < 1))
                            {
                                this.blens         = null;
                                this.mode          = InflateBlockMode.Bad;
                                this.Codec.Message = "invalid bit length repeat";
                                r = ZlibConstants.ZDataError;

                                this.Bitb = b;
                                this.Bitk = k;
                                this.Codec.AvailableBytesIn = n;
                                this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                                this.Codec.NextIn           = p;
                                this.WriteAt = q;
                                return(this.Flush(r));
                            }

                            c = (c == 16) ? this.blens[i - 1] : 0;
                            do
                            {
                                this.blens[i++] = c;
                            }while (--j != 0);
                            this.index = i;
                        }
                    }

                    this.tb[0] = -1;
                    {
                        var bl = new[] { 9 };     // must be <= 9 for lookahead assumptions
                        var bd = new[] { 6 };     // must be <= 9 for lookahead assumptions
                        var tl = new int[1];
                        var td = new int[1];

                        t = this.table;
                        t = this.inftree.InflateTreesDynamic(
                            257 + (t & 0x1f),
                            1 + ((t >> 5) & 0x1f),
                            this.blens,
                            bl,
                            bd,
                            tl,
                            td,
                            this.hufts,
                            this.Codec);

                        if (t != ZlibConstants.Zok)
                        {
                            if (t == ZlibConstants.ZDataError)
                            {
                                this.blens = null;
                                this.mode  = InflateBlockMode.Bad;
                            }

                            r = t;

                            this.Bitb = b;
                            this.Bitk = k;
                            this.Codec.AvailableBytesIn = n;
                            this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                            this.Codec.NextIn           = p;
                            this.WriteAt = q;
                            return(this.Flush(r));
                        }

                        this.codes.Init(bl[0], bd[0], this.hufts, tl[0], this.hufts, td[0]);
                    }

                    this.mode = InflateBlockMode.Codes;
                    goto case InflateBlockMode.Codes;

                case InflateBlockMode.Codes:
                    this.Bitb = b;
                    this.Bitk = k;
                    this.Codec.AvailableBytesIn = n;
                    this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                    this.Codec.NextIn           = p;
                    this.WriteAt = q;

                    r = this.codes.Process(this, r);
                    if (r != ZlibConstants.ZStreamEnd)
                    {
                        return(this.Flush(r));
                    }

                    r = ZlibConstants.Zok;
                    p = this.Codec.NextIn;
                    n = this.Codec.AvailableBytesIn;
                    b = this.Bitb;
                    k = this.Bitk;
                    q = this.WriteAt;
                    m = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;

                    if (this.last == 0)
                    {
                        this.mode = InflateBlockMode.Type;
                        break;
                    }

                    this.mode = InflateBlockMode.Dry;
                    goto case InflateBlockMode.Dry;

                case InflateBlockMode.Dry:
                    this.WriteAt = q;
                    r            = this.Flush(r);
                    q            = this.WriteAt;
                    m            = q < this.ReadAt ? this.ReadAt - q - 1 : this.End - q;
                    if (this.ReadAt != this.WriteAt)
                    {
                        this.Bitb = b;
                        this.Bitk = k;
                        this.Codec.AvailableBytesIn = n;
                        this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                        this.Codec.NextIn           = p;
                        this.WriteAt = q;
                        return(this.Flush(r));
                    }

                    this.mode = InflateBlockMode.Done;
                    goto case InflateBlockMode.Done;

                case InflateBlockMode.Done:
                    r         = ZlibConstants.ZStreamEnd;
                    this.Bitb = b;
                    this.Bitk = k;
                    this.Codec.AvailableBytesIn = n;
                    this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                    this.Codec.NextIn           = p;
                    this.WriteAt = q;
                    return(this.Flush(r));

                case InflateBlockMode.Bad:
                    r = ZlibConstants.ZDataError;

                    this.Bitb = b;
                    this.Bitk = k;
                    this.Codec.AvailableBytesIn = n;
                    this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                    this.Codec.NextIn           = p;
                    this.WriteAt = q;
                    return(this.Flush(r));

                default:
                    r = ZlibConstants.ZStreamError;

                    this.Bitb = b;
                    this.Bitk = k;
                    this.Codec.AvailableBytesIn = n;
                    this.Codec.TotalBytesIn    += p - this.Codec.NextIn;
                    this.Codec.NextIn           = p;
                    this.WriteAt = q;
                    return(this.Flush(r));
                }
            }
        }
示例#2
0
        internal int proc(ZStream z, int r)
        {
            int t;             // temporary storage
            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

            // copy input/output information to locals (UPDATE macro restores)
            {
                p = z.next_in_index; n = z.avail_in; b = bitb; k = bitk;
            }
            {
                q = write; m = (int)(q < read?read - q - 1:end - q);
            }

            // process input based on current state
            while (true)
            {
                switch (mode)
                {
                case TYPE:

                    while (k < (3))
                    {
                        if (n != 0)
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb        = b; bitk = k;
                            z.avail_in  = n;
                            z.total_in += p - z.next_in_index; z.next_in_index = p;
                            write       = q;
                            return(inflate_flush(z, r));
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }
                    t    = (int)(b & 7);
                    last = t & 1;

                    switch (SupportClass.URShift(t, 1))
                    {
                    case 0:                                      // stored
                    {
                        b = SupportClass.URShift(b, (3)); k -= (3);
                    }
                        t = k & 7;                                         // go to byte boundary

                        {
                            b = SupportClass.URShift(b, (t)); k -= (t);
                        }
                        mode = LENS;                                         // get length of stored block
                        break;

                    case 1:                                      // fixed
                    {
                        int[]   bl = new int[1];
                        int[]   bd = new int[1];
                        int[][] tl = new int[1][];
                        int[][] td = new int[1][];

                        InfTree.inflate_trees_fixed(bl, bd, tl, td, z);
                        codes = new InfCodes(bl[0], bd[0], tl[0], td[0], z);
                    }

                        {
                            b = SupportClass.URShift(b, (3)); k -= (3);
                        }

                        mode = CODES;
                        break;

                    case 2:                                      // dynamic

                    {
                        b = SupportClass.URShift(b, (3)); k -= (3);
                    }

                        mode = TABLE;
                        break;

                    case 3:                                      // illegal

                    {
                        b = SupportClass.URShift(b, (3)); k -= (3);
                    }
                        mode  = BAD;
                        z.msg = "invalid block type";
                        r     = Z_DATA_ERROR;

                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }
                    break;

                case LENS:

                    while (k < (32))
                    {
                        if (n != 0)
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb        = b; bitk = k;
                            z.avail_in  = n;
                            z.total_in += p - z.next_in_index; z.next_in_index = p;
                            write       = q;
                            return(inflate_flush(z, r));
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }

                    if (((SupportClass.URShift((~b), 16)) & 0xffff) != (b & 0xffff))
                    {
                        mode  = BAD;
                        z.msg = "invalid stored block lengths";
                        r     = Z_DATA_ERROR;

                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }
                    left = (b & 0xffff);
                    b    = k = 0;                          // dump bits
                    mode = left != 0?STORED:(last != 0?DRY:TYPE);
                    break;

                case STORED:
                    if (n == 0)
                    {
                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }

                    if (m == 0)
                    {
                        if (q == end && read != 0)
                        {
                            q = 0; m = (int)(q < read?read - q - 1:end - q);
                        }
                        if (m == 0)
                        {
                            write = q;
                            r     = inflate_flush(z, r);
                            q     = write; m = (int)(q < read?read - q - 1:end - q);
                            if (q == end && read != 0)
                            {
                                q = 0; m = (int)(q < read?read - q - 1:end - q);
                            }
                            if (m == 0)
                            {
                                bitb       = b; bitk = k;
                                z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                                write      = q;
                                return(inflate_flush(z, r));
                            }
                        }
                    }
                    r = Z_OK;

                    t = left;
                    if (t > n)
                    {
                        t = n;
                    }
                    if (t > m)
                    {
                        t = m;
                    }
                    Array.Copy(z.next_in, p, window, q, t);
                    p += t; n -= t;
                    q += t; m -= t;
                    if ((left -= t) != 0)
                    {
                        break;
                    }
                    mode = last != 0?DRY:TYPE;
                    break;

                case TABLE:

                    while (k < (14))
                    {
                        if (n != 0)
                        {
                            r = Z_OK;
                        }
                        else
                        {
                            bitb        = b; bitk = k;
                            z.avail_in  = n;
                            z.total_in += p - z.next_in_index; z.next_in_index = p;
                            write       = q;
                            return(inflate_flush(z, r));
                        }
                        ;
                        n--;
                        b |= (z.next_in[p++] & 0xff) << k;
                        k += 8;
                    }

                    table = t = (b & 0x3fff);
                    if ((t & 0x1f) > 29 || ((t >> 5) & 0x1f) > 29)
                    {
                        mode  = BAD;
                        z.msg = "too many length or distance symbols";
                        r     = Z_DATA_ERROR;

                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }
                    t     = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
                    blens = new int[t];

                    {
                        b = SupportClass.URShift(b, (14)); k -= (14);
                    }

                    index = 0;
                    mode  = BTREE;
                    goto case BTREE;

                case BTREE:
                    while (index < 4 + (SupportClass.URShift(table, 10)))
                    {
                        while (k < (3))
                        {
                            if (n != 0)
                            {
                                r = Z_OK;
                            }
                            else
                            {
                                bitb        = b; bitk = k;
                                z.avail_in  = n;
                                z.total_in += p - z.next_in_index; z.next_in_index = p;
                                write       = q;
                                return(inflate_flush(z, r));
                            }
                            ;
                            n--;
                            b |= (z.next_in[p++] & 0xff) << k;
                            k += 8;
                        }

                        blens[border[index++]] = b & 7;

                        {
                            b = SupportClass.URShift(b, (3)); k -= (3);
                        }
                    }

                    while (index < 19)
                    {
                        blens[border[index++]] = 0;
                    }

                    bb[0] = 7;
                    t     = InfTree.inflate_trees_bits(blens, bb, tb, hufts, z);
                    if (t != Z_OK)
                    {
                        r = t;
                        if (r == Z_DATA_ERROR)
                        {
                            blens = null;
                            mode  = BAD;
                        }

                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }

                    index = 0;
                    mode  = DTREE;
                    goto case DTREE;

                case DTREE:
                    while (true)
                    {
                        t = table;
                        if (!(index < 258 + (t & 0x1f) + ((t >> 5) & 0x1f)))
                        {
                            break;
                        }


                        int i, j, c;

                        t = bb[0];

                        while (k < (t))
                        {
                            if (n != 0)
                            {
                                r = Z_OK;
                            }
                            else
                            {
                                bitb        = b; bitk = k;
                                z.avail_in  = n;
                                z.total_in += p - z.next_in_index; z.next_in_index = p;
                                write       = q;
                                return(inflate_flush(z, r));
                            }
                            ;
                            n--;
                            b |= (z.next_in[p++] & 0xff) << k;
                            k += 8;
                        }

                        if (tb[0] == -1)
                        {
                            //System.err.println("null...");
                        }

                        t = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 1];
                        c = hufts[(tb[0] + (b & inflate_mask[t])) * 3 + 2];

                        if (c < 16)
                        {
                            b = SupportClass.URShift(b, (t)); k -= (t);
                            blens[index++] = c;
                        }
                        else
                        {
                            // c == 16..18
                            i = c == 18?7:c - 14;
                            j = c == 18?11:3;

                            while (k < (t + i))
                            {
                                if (n != 0)
                                {
                                    r = Z_OK;
                                }
                                else
                                {
                                    bitb        = b; bitk = k;
                                    z.avail_in  = n;
                                    z.total_in += p - z.next_in_index; z.next_in_index = p;
                                    write       = q;
                                    return(inflate_flush(z, r));
                                }
                                ;
                                n--;
                                b |= (z.next_in[p++] & 0xff) << k;
                                k += 8;
                            }

                            b = SupportClass.URShift(b, (t)); k -= (t);

                            j += (b & inflate_mask[i]);

                            b = SupportClass.URShift(b, (i)); k -= (i);

                            i = index;
                            t = table;
                            if (i + j > 258 + (t & 0x1f) + ((t >> 5) & 0x1f) || (c == 16 && i < 1))
                            {
                                blens = null;
                                mode  = BAD;
                                z.msg = "invalid bit length repeat";
                                r     = Z_DATA_ERROR;

                                bitb       = b; bitk = k;
                                z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                                write      = q;
                                return(inflate_flush(z, r));
                            }

                            c = c == 16?blens[i - 1]:0;
                            do
                            {
                                blens[i++] = c;
                            }while (--j != 0);
                            index = i;
                        }
                    }

                    tb[0] = -1;
                    {
                        int[] bl = new int[1];
                        int[] bd = new int[1];
                        int[] tl = new int[1];
                        int[] td = new int[1];


                        bl[0] = 9;                                 // must be <= 9 for lookahead assumptions
                        bd[0] = 6;                                 // must be <= 9 for lookahead assumptions
                        t     = table;
                        t     = InfTree.inflate_trees_dynamic(257 + (t & 0x1f), 1 + ((t >> 5) & 0x1f), blens, bl, bd, tl, td, hufts, z);
                        if (t != Z_OK)
                        {
                            if (t == Z_DATA_ERROR)
                            {
                                blens = null;
                                mode  = BAD;
                            }
                            r = t;

                            bitb       = b; bitk = k;
                            z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                            write      = q;
                            return(inflate_flush(z, r));
                        }

                        codes = new InfCodes(bl[0], bd[0], hufts, tl[0], hufts, td[0], z);
                    }
                    blens = null;
                    mode  = CODES;
                    goto case CODES;

                case CODES:
                    bitb       = b; bitk = k;
                    z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                    write      = q;

                    if ((r = codes.proc(this, z, r)) != Z_STREAM_END)
                    {
                        return(inflate_flush(z, r));
                    }
                    r = Z_OK;
                    codes.free(z);

                    p = z.next_in_index; n = z.avail_in; b = bitb; k = bitk;
                    q = write; m = (int)(q < read?read - q - 1:end - q);

                    if (last == 0)
                    {
                        mode = TYPE;
                        break;
                    }
                    mode = DRY;
                    goto case DRY;

                case DRY:
                    write = q;
                    r     = inflate_flush(z, r);
                    q     = write; m = (int)(q < read?read - q - 1:end - q);
                    if (read != write)
                    {
                        bitb       = b; bitk = k;
                        z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                        write      = q;
                        return(inflate_flush(z, r));
                    }
                    mode = DONE;
                    goto case DONE;

                case DONE:
                    r = Z_STREAM_END;

                    bitb       = b; bitk = k;
                    z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                    write      = q;
                    return(inflate_flush(z, r));

                case BAD:
                    r = Z_DATA_ERROR;

                    bitb       = b; bitk = k;
                    z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                    write      = q;
                    return(inflate_flush(z, r));


                default:
                    r = Z_STREAM_ERROR;

                    bitb       = b; bitk = k;
                    z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
                    write      = q;
                    return(inflate_flush(z, r));
                }
            }
        }