internal int deflate(ZStream strm, int flush)
{
int old_flush;
if (flush > Z_FINISH || flush < 0)
{
return Z_STREAM_ERROR;
}
if (strm.next_out == null || (strm.next_in == null && strm.avail_in != 0) || (status == FINISH_STATE && flush != Z_FINISH))
{
strm.msg = z_errmsg[Z_NEED_DICT - (Z_STREAM_ERROR)];
return Z_STREAM_ERROR;
}
if (strm.avail_out == 0)
{
strm.msg = z_errmsg[Z_NEED_DICT - (Z_BUF_ERROR)];
return 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 = ((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;
//nanook
//putShortMSB(header);
// Save the adler32 of the preset dictionary:
if (strstart != 0)
{
putShortMSB((int) (SupportClass.URShift(strm.adler, 16)));
putShortMSB((int) (strm.adler & 0xffff));
}
strm.adler = strm._adler.adler32(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 = - 1;
return Z_OK;
}
// Make sure there is something to do and avoid duplicate consecutive
// flushes. For repeated and useless calls with Z_FINISH, we keep
// returning Z_STREAM_END instead of Z_BUFF_ERROR.
}
else if (strm.avail_in == 0 && flush <= old_flush && flush != Z_FINISH)
{
strm.msg = z_errmsg[Z_NEED_DICT - (Z_BUF_ERROR)];
return 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[Z_NEED_DICT - (Z_BUF_ERROR)];
return Z_BUF_ERROR;
}
// Start a new block or continue the current one.
if (strm.avail_in != 0 || lookahead != 0 || (flush != Z_NO_FLUSH && status != FINISH_STATE))
{
int bstate = - 1;
switch (config_table[level].func)
{
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 = - 1; // avoid BUF_ERROR next call, see above
}
return Z_OK;
// If flush != 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 == 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 == Z_FULL_FLUSH)
{
//state.head[s.hash_size-1]=0;
for (int i = 0; i < hash_size; i++)
// forget history
head[i] = 0;
}
}
strm.flush_pending();
if (strm.avail_out == 0)
{
last_flush = - 1; // avoid BUF_ERROR at next call, see above
return Z_OK;
}
}
}
if (flush != Z_FINISH)
return Z_OK;
if (noheader != 0)
return Z_STREAM_END;
// Write the zlib trailer (adler32)
//Nanook - no trailer
//putShortMSB((int) (SupportClass.URShift(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?Z_OK:Z_STREAM_END;
}
