Copyright 1999-2003 John D. Polstra.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgment:
* This product includes software developed by John D. Polstra.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: StreamWrClass.m3.html,v 1.3 2010-04-29 17:20:11 wagner Exp $
MODULE StreamWrClass EXPORTS StreamWr, StreamWrClass;
IMPORT WrClass;
CONST
Threshold = LAST(CARDINAL) DIV 2;
PROCEDURE ByteCount(swr: T): LONGREAL =
BEGIN
WrClass.Lock(swr);
TRY
RETURN swr.offset + FLOAT(swr.cur, LONGREAL);
FINALLY
WrClass.Unlock(swr);
END;
END ByteCount;
PROCEDURE DontOverflow(swr: T) =
(* The writer is already locked. *)
BEGIN
IF swr.hi >= Threshold THEN
swr.offset := swr.offset + FLOAT(swr.lo, LONGREAL);
DEC(swr.hi, swr.lo);
DEC(swr.cur, swr.lo);
swr.lo := 0;
END;
END DontOverflow;
BEGIN
END StreamWrClass.