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
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* 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
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
MODULE StreamRdClass EXPORTS StreamRd, StreamRdClass;
IMPORT RdClass;
CONST
Threshold = LAST(CARDINAL) DIV 2;
PROCEDURE ByteCount(srd: T): LONGREAL =
BEGIN
RdClass.Lock(srd);
TRY
RETURN srd.offset + FLOAT(srd.cur, LONGREAL);
FINALLY
RdClass.Unlock(srd);
END;
END ByteCount;
PROCEDURE DontOverflow(srd: T) =
(* The reader is already locked. *)
BEGIN
IF srd.hi >= Threshold THEN
srd.offset := srd.offset + FLOAT(srd.lo, LONGREAL);
DEC(srd.hi, srd.lo);
DEC(srd.cur, srd.lo);
srd.lo := 0;
END;
END DontOverflow;
BEGIN
END StreamRdClass.