/// <summary>
/// copy as much as possible from the sliding Window to the output area
/// </summary>
internal int inflate_flush(ZStream z, int r)
{
int n;
int p;
int q;
// local copies of source and destination pointers
p = z.next_out_index;
q = ReadPos;
// compute number of bytes to copy as far as End of Window
n = (int)((q <= WritePos?WritePos:End) - q);
if (n > z.avail_out)
{
n = z.avail_out;
}
if (n != 0 && r == (int)ZLibResultCode.Z_BUF_ERROR)
{
r = (int)ZLibResultCode.Z_OK;
}
// update counters
z.avail_out -= n;
z.total_out += n;
// update check information
if (this.needCheck)
{
z.adler = check = Adler32.GetAdler32Checksum(check, Window, q, n);
}
// copy as far as End of Window
Array.Copy(Window, q, z.next_out, p, n);
p += n;
q += n;
// see if more to copy at beginning of Window
if (q == End)
{
// wrap pointers
q = 0;
if (WritePos == End)
{
WritePos = 0;
}
// compute bytes to copy
n = WritePos - q;
if (n > z.avail_out)
{
n = z.avail_out;
}
if (n != 0 && r == (int)ZLibResultCode.Z_BUF_ERROR)
{
r = (int)ZLibResultCode.Z_OK;
}
// update counters
z.avail_out -= n;
z.total_out += n;
// update check information
if (this.needCheck)
{
z.adler = check = Adler32.GetAdler32Checksum(check, Window, q, n);
}
// copy
Array.Copy(Window, q, z.next_out, p, n);
p += n;
q += n;
}
// update pointers
z.next_out_index = p;
ReadPos = q;
// done
return(r);
}
/// <summary>
/// Block processing functions
/// </summary>
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 WritePos pointer
int m; // bytes to End of Window or ReadPos pointer
// copy input/output information to locals (UPDATE macro restores)
{
p = z.next_in_index; n = z.avail_in; b = BitB; k = BitK;
}
{
q = WritePos; m = (int)(q < ReadPos ? ReadPos - q - 1 : End - q);
}
// process input based on current state
while (true)
{
switch (mode)
{
case InflateBlockMode.TYPE:
while (k < (3))
{
if (n != 0)
{
r = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
;
n--;
b |= (z.next_in[p++] & 0xff) << k;
k += 8;
}
t = (int)(b & 7);
last = t & 1;
switch (ZLibUtil.URShift(t, 1))
{
case 0: // stored
{
b = ZLibUtil.URShift(b, (3)); k -= (3);
}
t = k & 7; // go to byte boundary
{
b = ZLibUtil.URShift(b, (t)); k -= (t);
}
mode = InflateBlockMode.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 = ZLibUtil.URShift(b, (3)); k -= (3);
}
mode = InflateBlockMode.CODES;
break;
case 2: // dynamic
{
b = ZLibUtil.URShift(b, (3)); k -= (3);
}
mode = InflateBlockMode.TABLE;
break;
case 3: // illegal
{
b = ZLibUtil.URShift(b, (3)); k -= (3);
}
mode = InflateBlockMode.BAD;
z.msg = "invalid block type";
r = (int)ZLibResultCode.Z_DATA_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
break;
case InflateBlockMode.LENS:
while (k < (32))
{
if (n != 0)
{
r = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
;
n--;
b |= (z.next_in[p++] & 0xff) << k;
k += 8;
}
if (((ZLibUtil.URShift((~b), 16)) & 0xffff) != (b & 0xffff))
{
mode = InflateBlockMode.BAD;
z.msg = "invalid stored block lengths";
r = (int)ZLibResultCode.Z_DATA_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
left = (b & 0xffff);
b = k = 0; // dump bits
mode = (left != 0) ? InflateBlockMode.STORED : (last != 0 ? InflateBlockMode.DRY : InflateBlockMode.TYPE);
break;
case InflateBlockMode.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;
WritePos = q;
return(inflate_flush(z, r));
}
if (m == 0)
{
if (q == End && ReadPos != 0)
{
q = 0; m = (int)(q < ReadPos ? ReadPos - q - 1 : End - q);
}
if (m == 0)
{
WritePos = q;
r = inflate_flush(z, r);
q = WritePos; m = (int)(q < ReadPos ? ReadPos - q - 1 : End - q);
if (q == End && ReadPos != 0)
{
q = 0; m = (int)(q < ReadPos ? ReadPos - 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;
WritePos = q;
return(inflate_flush(z, r));
}
}
}
r = (int)ZLibResultCode.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 ? InflateBlockMode.DRY : InflateBlockMode.TYPE;
break;
case InflateBlockMode.TABLE:
while (k < (14))
{
if (n != 0)
{
r = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = 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 = InflateBlockMode.BAD;
z.msg = "too many length or distance symbols";
r = (int)ZLibResultCode.Z_DATA_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
t = 258 + (t & 0x1f) + ((t >> 5) & 0x1f);
blens = new int[t];
{
b = ZLibUtil.URShift(b, (14)); k -= (14);
}
index = 0;
mode = InflateBlockMode.BTREE;
goto case InflateBlockMode.BTREE;
case InflateBlockMode.BTREE:
while (index < 4 + (ZLibUtil.URShift(table, 10)))
{
while (k < (3))
{
if (n != 0)
{
r = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
;
n--;
b |= (z.next_in[p++] & 0xff) << k;
k += 8;
}
blens[ZLibUtil.border[index++]] = b & 7;
{
b = ZLibUtil.URShift(b, (3)); k -= (3);
}
}
while (index < 19)
{
blens[ZLibUtil.border[index++]] = 0;
}
bb[0] = 7;
t = InfTree.inflate_trees_bits(blens, bb, tb, hufts, z);
if (t != (int)ZLibResultCode.Z_OK)
{
r = t;
if (r == (int)ZLibResultCode.Z_DATA_ERROR)
{
blens = null;
mode = InflateBlockMode.BAD;
}
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
index = 0;
mode = InflateBlockMode.DTREE;
goto case InflateBlockMode.DTREE;
case InflateBlockMode.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 = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
;
n--;
b |= (z.next_in[p++] & 0xff) << k;
k += 8;
}
t = hufts[(tb[0] + (b & ZLibUtil.inflate_mask[t])) * 3 + 1];
c = hufts[(tb[0] + (b & ZLibUtil.inflate_mask[t])) * 3 + 2];
if (c < 16)
{
b = ZLibUtil.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 = (int)ZLibResultCode.Z_OK;
}
else
{
BitB = b; BitK = k;
z.avail_in = n;
z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
;
n--;
b |= (z.next_in[p++] & 0xff) << k;
k += 8;
}
b = ZLibUtil.URShift(b, (t)); k -= (t);
j += (b & ZLibUtil.inflate_mask[i]);
b = ZLibUtil.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 = InflateBlockMode.BAD;
z.msg = "invalid bit length repeat";
r = (int)ZLibResultCode.Z_DATA_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = 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 != (int)ZLibResultCode.Z_OK)
{
if (t == (int)ZLibResultCode.Z_DATA_ERROR)
{
blens = null;
mode = InflateBlockMode.BAD;
}
r = t;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
codes = new InfCodes(bl[0], bd[0], hufts, tl[0], hufts, td[0], z);
}
blens = null;
mode = InflateBlockMode.CODES;
goto case InflateBlockMode.CODES;
case InflateBlockMode.CODES:
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
if ((r = codes.proc(this, z, r)) != (int)ZLibResultCode.Z_STREAM_END)
{
return(inflate_flush(z, r));
}
r = (int)ZLibResultCode.Z_OK;
codes.free(z);
p = z.next_in_index; n = z.avail_in; b = BitB; k = BitK;
q = WritePos; m = (int)(q < ReadPos ? ReadPos - q - 1 : End - q);
if (last == 0)
{
mode = InflateBlockMode.TYPE;
break;
}
mode = InflateBlockMode.DRY;
goto case InflateBlockMode.DRY;
case InflateBlockMode.DRY:
WritePos = q;
r = inflate_flush(z, r);
q = WritePos; m = (int)(q < ReadPos ? ReadPos - q - 1 : End - q);
if (ReadPos != WritePos)
{
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
mode = InflateBlockMode.DONE;
goto case InflateBlockMode.DONE;
case InflateBlockMode.DONE:
r = (int)ZLibResultCode.Z_STREAM_END;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
case InflateBlockMode.BAD:
r = (int)ZLibResultCode.Z_DATA_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
default:
r = (int)ZLibResultCode.Z_STREAM_ERROR;
BitB = b; BitK = k;
z.avail_in = n; z.total_in += p - z.next_in_index; z.next_in_index = p;
WritePos = q;
return(inflate_flush(z, r));
}
}
}