RealExceptions.mesa
Copyright © 1985 by Xerox Corporation. All rights reserved.
Russ Atkinson (RRA) May 22, 1985 12:50:27 pm PDT
DIRECTORY
Basics USING [LongNumber],
PrincOps USING [PsbIndex],
Real USING [Exception, ExceptionFlags, Extended];
RealExceptions: CEDAR DEFINITIONS = BEGIN
FlagsArray: TYPE = ARRAY PrincOps.PsbIndex OF CombinedFlags;
CombinedFlags:
TYPE =
RECORD [
sticky: Real.ExceptionFlags,
exceptions: Real.ExceptionFlags
];
Init:
UNSAFE PROC [lp:
LONG
POINTER
TO FlagsArray];
Must be called to enable multi-process REAL exception handling.
ClearExceptions:
PROC;
Clear the exceptions for the current process
ClearSticky:
PROC;
Clear the sticky bits for the current process
ClearCombined:
PROC;
Clear the exceptions & sticky bits for the current process
SetCombined:
PROC [flags: CombinedFlags];
Sets the exception bits & sticky bits for the current process
SetException:
PROC [which: Real.Exception];
Sets a given exception for the current process
SetSticky:
PROC [which: Real.Exception];
Sets a given sticky bit for the current process
TestException:
PROC [which: Real.Exception]
RETURNS [
BOOL];
Tests a particular exception for the current process
TestSticky:
PROC [which: Real.Exception]
RETURNS [
BOOL];
Tests a particular sticky bit for the current process
GetExceptions:
PROC
RETURNS [Real.ExceptionFlags];
Samples the exceptions for the current process
GetSticky:
PROC
RETURNS [Real.ExceptionFlags];
Samples the sticky bits for the current process
GetCombined:
PROC
RETURNS [CombinedFlags];
Samples the exceptions & sticky bits for the current process
RaiseException:
PROC [ext: Real.Extended]
RETURNS [clientFixup:
BOOL, fraction: Basics.LongNumber];
Raises Real.RealException with the current exception flags and the given extended number. Returns whatever the client directed if the client RESUMEs the signal.
END.