System.util.zlib.InfCodes.proc C# (CSharp) Méthode

proc() private méthode

private proc ( InfBlocks s, ZStream z, int r ) : int
s InfBlocks
z ZStream
r int
Résultat int
        internal int proc(InfBlocks s, ZStream z, 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

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

                            s.bitb=b;s.bitk=k;
                            z.avail_in=n;z.total_in+=p-z.next_in_index;z.next_in_index=p;
                            s.write=q;
                            r = inflate_fast(lbits, dbits,
                                ltree, ltree_index,
                                dtree, dtree_index,
                                s, z);

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

                            if (r != Z_OK){
                                mode = r == 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=Z_OK;
                            else{

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

                        tindex=(tree_index+(b&inflate_mask[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
                            get = 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.msg = "invalid literal/length code";
                        r = Z_DATA_ERROR;

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

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

                        while(k<(j)){
                            if(n!=0)r=Z_OK;
                            else{

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

                        len += (b & inflate_mask[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=Z_OK;
                            else{

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

                        tindex=(tree_index+(b & inflate_mask[j]))*3;

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

                        e = (tree[tindex]);
                        if((e & 16)!=0){               // distance
                            get = 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.msg = "invalid distance code";
                        r = Z_DATA_ERROR;

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

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

                        while(k<(j)){
                            if(n!=0)r=Z_OK;
                            else{

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

                        dist += (b & inflate_mask[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 += s.end;     // of "if" handles invalid distances
                        }
                        while (len!=0){

                            if(m==0){
                                if(q==s.end&&s.read!=0){q=0;m=q<s.read?s.read-q-1:s.end-q;}
                                if(m==0){
                                    s.write=q; r=s.inflate_flush(z,r);
                                    q=s.write;m=q<s.read?s.read-q-1:s.end-q;

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

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

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

                            if (f == s.end)
                                f = 0;
                            len--;
                        }
                        mode = START;
                        break;
                    case LIT:           // o: got literal, waiting for output space
                        if(m==0){
                            if(q==s.end&&s.read!=0){q=0;m=q<s.read?s.read-q-1:s.end-q;}
                            if(m==0){
                                s.write=q; r=s.inflate_flush(z,r);
                                q=s.write;m=q<s.read?s.read-q-1:s.end-q;

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

                        s.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
                        }

                        s.write=q; r=s.inflate_flush(z,r);
                        q=s.write;m=q<s.read?s.read-q-1:s.end-q;

                        if (s.read != s.write){
                            s.bitb=b;s.bitk=k;
                            z.avail_in=n;z.total_in+=p-z.next_in_index;z.next_in_index=p;
                            s.write=q;
                            return s.inflate_flush(z,r);
                        }
                        mode = END;
                        goto case END;
                    case END:
                        r = Z_STREAM_END;
                        s.bitb=b;s.bitk=k;
                        z.avail_in=n;z.total_in+=p-z.next_in_index;z.next_in_index=p;
                        s.write=q;
                        return s.inflate_flush(z,r);

                    case BADCODE:       // x: got error

                        r = Z_DATA_ERROR;

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

                    default:
                        r = Z_STREAM_ERROR;

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

Usage Example

Exemple #1
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 (t >> 1)
                    {
                    case 0: {                             // stored
                        b >>= (3); k -= (3);
                    }
                        t = k & 7; {                        // go to byte boundary
                            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.init(bl[0], bd[0], tl[0], 0, td[0], 0, z);
                    } {
                            b >>= (3); k -= (3);
                    }

                        mode = CODES;
                        break;

                    case 2: {                             // dynamic
                        b >>= (3); k -= (3);
                    }

                        mode = TABLE;
                        break;

                    case 3: {                             // illegal
                        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 ((((~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;
                    }
                    System.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);
                    if (blens == null || blens.Length < t)
                    {
                        blens = new int[t];
                    }
                    else
                    {
                        for (int i = 0; i < t; i++)
                        {
                            blens[i] = 0;
                        }
                    } {
                        b >>= (14); k -= (14);
                    }

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

                case BTREE:
                    while (index < 4 + (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 >>= (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 >>= (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 >>= (t); k -= (t);

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

                            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.init(bl[0], bd[0], hufts, tl[0], hufts, td[0], z);
                    }
                    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));
                }
            }
        }