118 lines
2.1 KiB
C
118 lines
2.1 KiB
C
|
/*++
|
|||
|
|
|
|||
|
|
Copyright (c) 1989 Microsoft Corporation
|
|||
|
|
|
|||
|
|
Module Name:
|
|||
|
|
|
|||
|
|
intrloc2.c
|
|||
|
|
|
|||
|
|
Abstract:
|
|||
|
|
|
|||
|
|
This module implements the *portable* (i.e. SLOW) versions of
|
|||
|
|
the executive's simple atomic increment/decrement procedures.
|
|||
|
|
Real implementation should be in assembler.
|
|||
|
|
|
|||
|
|
Author:
|
|||
|
|
|
|||
|
|
Bryan Willman (bryanwi) 2-Aug-90
|
|||
|
|
|
|||
|
|
Environment:
|
|||
|
|
|
|||
|
|
Kernel mode only.
|
|||
|
|
|
|||
|
|
Revision History:
|
|||
|
|
|
|||
|
|
--*/
|
|||
|
|
|
|||
|
|
#include "exp.h"
|
|||
|
|
|
|||
|
|
INTERLOCKED_RESULT
|
|||
|
|
ExInterlockedIncrementLong (
|
|||
|
|
IN PLONG Addend,
|
|||
|
|
IN PKSPIN_LOCK Lock
|
|||
|
|
)
|
|||
|
|
|
|||
|
|
/*++
|
|||
|
|
|
|||
|
|
Routine Description:
|
|||
|
|
|
|||
|
|
This function atomically increments Addend, returning an ennumerated
|
|||
|
|
type which indicates what interesting transitions in the value of
|
|||
|
|
Addend occurred due the operation.
|
|||
|
|
|
|||
|
|
Arguments:
|
|||
|
|
|
|||
|
|
Addend - Pointer to variable to increment.
|
|||
|
|
|
|||
|
|
Lock - Spinlock used to implement atomicity.
|
|||
|
|
|
|||
|
|
Return Value:
|
|||
|
|
|
|||
|
|
An ennumerated type:
|
|||
|
|
|
|||
|
|
ResultNegative if Addend is < 0 after increment.
|
|||
|
|
ResultZero if Addend is = 0 after increment.
|
|||
|
|
ResultPositive if Addend is > 0 after increment.
|
|||
|
|
|
|||
|
|
--*/
|
|||
|
|
|
|||
|
|
{
|
|||
|
|
LONG OldValue;
|
|||
|
|
|
|||
|
|
OldValue = (LONG)ExInterlockedAddUlong((PULONG)Addend, 1, Lock);
|
|||
|
|
|
|||
|
|
if (OldValue < -1)
|
|||
|
|
return ResultNegative;
|
|||
|
|
|
|||
|
|
if (OldValue == -1)
|
|||
|
|
return ResultZero;
|
|||
|
|
|
|||
|
|
if (OldValue > -1)
|
|||
|
|
return ResultPositive;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
INTERLOCKED_RESULT
|
|||
|
|
ExInterlockedDecrementLong (
|
|||
|
|
IN PLONG Addend,
|
|||
|
|
IN PKSPIN_LOCK Lock
|
|||
|
|
)
|
|||
|
|
|
|||
|
|
/*++
|
|||
|
|
|
|||
|
|
Routine Description:
|
|||
|
|
|
|||
|
|
This function atomically decrements Addend, returning an ennumerated
|
|||
|
|
type which indicates what interesting transitions in the value of
|
|||
|
|
Addend occurred due the operation.
|
|||
|
|
|
|||
|
|
Arguments:
|
|||
|
|
|
|||
|
|
Addend - Pointer to variable to decrement.
|
|||
|
|
|
|||
|
|
Lock - Spinlock used to implement atomicity.
|
|||
|
|
|
|||
|
|
Return Value:
|
|||
|
|
|
|||
|
|
An ennumerated type:
|
|||
|
|
|
|||
|
|
ResultNegative if Addend is < 0 after decrement.
|
|||
|
|
ResultZero if Addend is = 0 after decrement.
|
|||
|
|
ResultPositive if Addend is > 0 after decrement.
|
|||
|
|
|
|||
|
|
--*/
|
|||
|
|
|
|||
|
|
{
|
|||
|
|
LONG OldValue;
|
|||
|
|
|
|||
|
|
OldValue = (LONG)ExInterlockedAddUlong((PULONG)Addend, -1, Lock);
|
|||
|
|
|
|||
|
|
if (OldValue > 1)
|
|||
|
|
return ResultPositive;
|
|||
|
|
|
|||
|
|
if (OldValue == 1)
|
|||
|
|
return ResultZero;
|
|||
|
|
|
|||
|
|
if (OldValue < 1)
|
|||
|
|
return ResultNegative;
|
|||
|
|
}
|