/// <summary>
/// copy as much as possible from the sliding window to the output area
/// </summary>
/// <param name="z">The z.</param>
/// <param name="r">The r.</param>
/// <returns></returns>
public ZLibStatus InflateFlush(ZStream z, ZLibStatus r)
{
int n;
int p;
int q;
// local copies of source and destination pointers
p = z.next_out_index;
q = read;
// compute number of bytes to copy as far as end of window
n = (int)((q <= write ? write : end) - q);
if (n > z.avail_out) n = z.avail_out;
if (n != 0 && r == ZLibStatus.Z_BUF_ERROR)
r = ZLibStatus.Z_OK;
// update counters
z.avail_out -= n;
z.total_out += n;
// update check information
if (checkfn != null)
{
//z.adler = check = z.Adler32(check, window, q, n);
z.UpdateAdler(check, window, q, n);
check = z.Adler;
}
// copy as far as end of window
System.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 (write == end)
write = 0;
// compute bytes to copy
n = write - q;
if (n > z.avail_out) n = z.avail_out;
if (n != 0 && r == ZLibStatus.Z_BUF_ERROR)
r = ZLibStatus.Z_OK;
// update counters
z.avail_out -= n;
z.total_out += n;
// update check information
if (checkfn != null)
{
//z.adler = check = z.Adler32(check, window, q, n);
z.UpdateAdler(check, window, q, n);
check = z.Adler;
}
// copy
System.Array.Copy(window, q, z.next_out, p, n);
p += n;
q += n;
}
// update pointers
z.next_out_index = p;
read = q;
// done
return r;
}
public void Reset(ZStream z, long[] c)
{
if (c != null) c[0] = check;
if (mode == InflateBlockMode.BTREE || mode == InflateBlockMode.DTREE)
{
}
//if (mode == InflateBlockMode.CODES)
//{
// codes.free(z);
//}
mode = InflateBlockMode.TYPE;
bitk = 0;
bitb = 0;
read = write = 0;
if (checkfn != null)
{
//z.adler = check = z.Adler32(0L, null, 0, 0);
z.UpdateAdler(0L, null, 0, 0);
check = z.Adler;
}
}
public ZLibStatus deflateSetDictionary(ZStream strm, byte[] dictionary, int dictLength)
{
int length = dictLength;
int index = 0;
if (dictionary == null || status != INIT_STATE)
return ZLibStatus.Z_STREAM_ERROR;
//strm.adler = strm.Adler32(strm.adler, dictionary, 0, dictLength);
strm.UpdateAdler(dictionary, 0, dictLength);
if (length < MIN_MATCH) return ZLibStatus.Z_OK;
if (length > w_size - MIN_LOOKAHEAD)
{
length = w_size - MIN_LOOKAHEAD;
index = dictLength - length; // use the tail of the dictionary
}
System.Array.Copy(dictionary, index, window, 0, length);
strstart = length;
block_start = length;
// Insert all strings in the hash table (except for the last two bytes).
// s->lookahead stays null, so s->ins_h will be recomputed at the next
// call of fill_window.
ins_h = window[0] & 0xff;
ins_h = (((ins_h) << hash_shift) ^ (window[1] & 0xff)) & hash_mask;
for (int n = 0; n <= length - MIN_MATCH; n++)
{
ins_h = (((ins_h) << hash_shift) ^ (window[(n) + (MIN_MATCH - 1)] & 0xff)) & hash_mask;
prev[n & w_mask] = head[ins_h];
head[ins_h] = (short)n;
}
return ZLibStatus.Z_OK;
}
public ZLibStatus deflate(ZStream strm, FlushType flush)
{
FlushType old_flush;
if (flush > FlushType.Z_FINISH || flush < 0)
{
return ZLibStatus.Z_STREAM_ERROR;
}
if (strm.next_out == null ||
(strm.next_in == null && strm.avail_in != 0) ||
(status == FINISH_STATE && flush != FlushType.Z_FINISH))
{
strm.msg = z_errmsg[ZLibStatus.Z_NEED_DICT - (ZLibStatus.Z_STREAM_ERROR)];
return ZLibStatus.Z_STREAM_ERROR;
}
if (strm.avail_out == 0)
{
strm.msg = z_errmsg[ZLibStatus.Z_NEED_DICT - (ZLibStatus.Z_BUF_ERROR)];
return ZLibStatus.Z_BUF_ERROR;
}
this.strm = strm; // just in case
old_flush = last_flush;
last_flush = flush;
// Write the zlib header
if (status == INIT_STATE)
{
int header = (Z_DEFLATED + ((w_bits - 8) << 4)) << 8;
int level_flags = (((int)level - 1) & 0xff) >> 1;
if (level_flags > 3) level_flags = 3;
header |= (level_flags << 6);
if (strstart != 0) header |= PRESET_DICT;
header += 31 - (header % 31);
status = BUSY_STATE;
putShortMSB(header);
// Save the adler32 of the preset dictionary:
if (strstart != 0)
{
putShortMSB((int)(strm.Adler >> 16));
putShortMSB((int)(strm.Adler & 0xffff));
}
//strm.adler = strm.Adler32(0, null, 0, 0);
strm.UpdateAdler(0, null, 0, 0);
}
// Flush as much pending output as possible
if (pending != 0)
{
strm.flush_pending();
if (strm.avail_out == 0)
{
//System.out.println(" avail_out==0");
// Since avail_out is 0, deflate will be called again with
// more output space, but possibly with both pending and
// avail_in equal to zero. There won't be anything to do,
// but this is not an error situation so make sure we
// return OK instead of BUF_ERROR at next call of deflate:
last_flush = (FlushType)(-1);
return ZLibStatus.Z_OK;
}
// Make sure there is something to do and avoid duplicate consecutive
// flushes. For repeated and useless calls with FlushType.Z_FINISH, we keep
// returning ZLibStatus.Z_STREAM_END instead of Z_BUFF_ERROR.
}
else if (strm.avail_in == 0 && flush <= old_flush &&
flush != FlushType.Z_FINISH)
{
strm.msg = z_errmsg[ZLibStatus.Z_NEED_DICT - (ZLibStatus.Z_BUF_ERROR)];
return ZLibStatus.Z_BUF_ERROR;
}
// User must not provide more input after the first FINISH:
if (status == FINISH_STATE && strm.avail_in != 0)
{
strm.msg = z_errmsg[ZLibStatus.Z_NEED_DICT - (ZLibStatus.Z_BUF_ERROR)];
return ZLibStatus.Z_BUF_ERROR;
}
// Start a new block or continue the current one.
if (strm.avail_in != 0 || lookahead != 0 ||
(flush != FlushType.Z_NO_FLUSH && status != FINISH_STATE))
{
int bstate = -1;
switch (_configurationTable[level].Function)
{
case STORED:
bstate = deflate_stored(flush);
break;
case FAST:
bstate = deflate_fast(flush);
break;
case SLOW:
bstate = deflate_slow(flush);
break;
default:
break;
}
if (bstate == FinishStarted || bstate == FinishDone)
{
status = FINISH_STATE;
}
if (bstate == NeedMore || bstate == FinishStarted)
{
if (strm.avail_out == 0)
{
last_flush = (FlushType)(-1); // avoid BUF_ERROR next call, see above
}
return ZLibStatus.Z_OK;
// If flush != FlushType.Z_NO_FLUSH && avail_out == 0, the next call
// of deflate should use the same flush parameter to make sure
// that the flush is complete. So we don't have to output an
// empty block here, this will be done at next call. This also
// ensures that for a very small output buffer, we emit at most
// one empty block.
}
if (bstate == BlockDone)
{
if (flush == FlushType.Z_PARTIAL_FLUSH)
{
_tr_align();
}
else
{ // FULL_FLUSH or SYNC_FLUSH
_tr_stored_block(0, 0, false);
// For a full flush, this empty block will be recognized
// as a special marker by inflate_sync().
if (flush == FlushType.Z_FULL_FLUSH)
{
//state.head[s.hash_size-1]=0;
for (int i = 0; i < hash_size/*-1*/; i++) // forget history
head[i] = 0;
}
}
strm.flush_pending();
if (strm.avail_out == 0)
{
last_flush = (FlushType)(-1); // avoid BUF_ERROR at next call, see above
return ZLibStatus.Z_OK;
}
}
}
if (flush != FlushType.Z_FINISH) return ZLibStatus.Z_OK;
if (noheader != 0) return ZLibStatus.Z_STREAM_END;
// Write the zlib trailer (adler32)
putShortMSB((int)(strm.Adler >> 16));
putShortMSB((int)(strm.Adler & 0xffff));
strm.flush_pending();
// If avail_out is zero, the application will call deflate again
// to flush the rest.
noheader = -1; // write the trailer only once!
return pending != 0 ? ZLibStatus.Z_OK : ZLibStatus.Z_STREAM_END;
}
private ZLibStatus deflateReset(ZStream strm)
{
strm.total_in = strm.total_out = 0;
strm.msg = null; //
//strm.data_type = Z_UNKNOWN;
pending = 0;
pending_out = 0;
if (noheader < 0)
{
noheader = 0; // was set to -1 by deflate(..., FlushType.Z_FINISH);
}
status = (noheader != 0) ? BUSY_STATE : INIT_STATE;
//strm.adler = strm.Adler32(0, null, 0, 0);
strm.UpdateAdler(0L, null, 0, 0);
last_flush = FlushType.Z_NO_FLUSH;
tr_init();
lm_init();
return ZLibStatus.Z_OK;
}