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[RTL] Implement RtlTryAcquireSRWLockExclusive & RtlTryAcquireSRWLockShared

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This commit is contained in:
Jérôme Gardou 2021-01-29 18:41:38 +01:00
parent 2486558ae1
commit 6a4c6ea5d0
2 changed files with 77 additions and 4 deletions
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43
sdk/include/ndk/rtlfuncs.h
View file

@ -4888,6 +4888,49 @@ RtlGetNativeSystemInformation(
_Out_opt_ PULONG ReturnLength
);
#if (_WIN32_WINNT >= _WIN32_WINNT_VISTA) || (defined(__REACTOS__) && defined(_NTDLLBUILD_))
/* Put NTSYSAPI back when this will be really exported. Only statically linked for now */
// NTSYSAPI
VOID
NTAPI
RtlInitializeSRWLock(OUT PRTL_SRWLOCK SRWLock);
// NTSYSAPI
VOID
NTAPI
RtlAcquireSRWLockShared(IN OUT PRTL_SRWLOCK SRWLock);
// NTSYSAPI
VOID
NTAPI
RtlAcquireSRWLockExclusive(IN OUT PRTL_SRWLOCK SRWLock);
// NTSYSAPI
VOID
NTAPI
RtlReleaseSRWLockShared(IN OUT PRTL_SRWLOCK SRWLock);
// NTSYSAPI
VOID
NTAPI
RtlReleaseSRWLockExclusive(IN OUT PRTL_SRWLOCK SRWLock);
#endif /* Win vista or Reactos Ntdll build */
#if (_WIN32_WINNT >= _WIN32_WINNT_WIN7) || (defined(__REACTOS__) && defined(_NTDLLBUILD_))
// NTSYSAPI
BOOLEAN
NTAPI
RtlTryAcquireSRWLockShared(PRTL_SRWLOCK SRWLock);
// NTSYSAPI
BOOLEAN
NTAPI
RtlTryAcquireSRWLockExclusive(PRTL_SRWLOCK SRWLock);
#endif /* Win7 or Reactos Ntdll build */
#endif // NTOS_MODE_USER
NTSYSAPI

38
sdk/lib/rtl/srw.c
View file

@ -25,21 +25,23 @@
#define InterlockedAddPointer(ptr,val) InterlockedAdd64((PLONGLONG)ptr,(LONGLONG)val)
#define InterlockedAndPointer(ptr,val) InterlockedAnd64((PLONGLONG)ptr,(LONGLONG)val)
#define InterlockedOrPointer(ptr,val) InterlockedOr64((PLONGLONG)ptr,(LONGLONG)val)
#define _ONE 1LL
#else
#define InterlockedBitTestAndSetPointer(ptr,val) InterlockedBitTestAndSet((PLONG)ptr,(LONG)val)
#define InterlockedAddPointer(ptr,val) InterlockedAdd((PLONG)ptr,(LONG)val)
#define InterlockedAndPointer(ptr,val) InterlockedAnd((PLONG)ptr,(LONG)val)
#define InterlockedOrPointer(ptr,val) InterlockedOr((PLONG)ptr,(LONG)val)
#define _ONE 1L
#endif
#define RTL_SRWLOCK_OWNED_BIT 0
#define RTL_SRWLOCK_CONTENDED_BIT 1
#define RTL_SRWLOCK_SHARED_BIT 2
#define RTL_SRWLOCK_CONTENTION_LOCK_BIT 3
#define RTL_SRWLOCK_OWNED (1 << RTL_SRWLOCK_OWNED_BIT)
#define RTL_SRWLOCK_CONTENDED (1 << RTL_SRWLOCK_CONTENDED_BIT)
#define RTL_SRWLOCK_SHARED (1 << RTL_SRWLOCK_SHARED_BIT)
#define RTL_SRWLOCK_CONTENTION_LOCK (1 << RTL_SRWLOCK_CONTENTION_LOCK_BIT)
#define RTL_SRWLOCK_OWNED (_ONE << RTL_SRWLOCK_OWNED_BIT)
#define RTL_SRWLOCK_CONTENDED (_ONE << RTL_SRWLOCK_CONTENDED_BIT)
#define RTL_SRWLOCK_SHARED (_ONE << RTL_SRWLOCK_SHARED_BIT)
#define RTL_SRWLOCK_CONTENTION_LOCK (_ONE << RTL_SRWLOCK_CONTENTION_LOCK_BIT)
#define RTL_SRWLOCK_MASK (RTL_SRWLOCK_OWNED | RTL_SRWLOCK_CONTENDED | \
RTL_SRWLOCK_SHARED | RTL_SRWLOCK_CONTENTION_LOCK)
#define RTL_SRWLOCK_BITS 4
@ -763,3 +765,31 @@ RtlReleaseSRWLockExclusive(IN OUT PRTL_SRWLOCK SRWLock)
YieldProcessor();
}
}
BOOLEAN
NTAPI
RtlTryAcquireSRWLockShared(PRTL_SRWLOCK SRWLock)
{
LONG_PTR CompareValue, NewValue, GotValue;
do
{
CompareValue = *(volatile LONG_PTR *)&SRWLock->Ptr;
NewValue = ((CompareValue >> RTL_SRWLOCK_BITS) + 1) | RTL_SRWLOCK_SHARED | RTL_SRWLOCK_OWNED;
/* Only increment shared count if there is no waiter */
CompareValue &= ~RTL_SRWLOCK_MASK | RTL_SRWLOCK_SHARED | RTL_SRWLOCK_OWNED;
} while (
((GotValue = (LONG_PTR)InterlockedCompareExchangePointer(&SRWLock->Ptr, (LONG_PTR*)NewValue, (LONG_PTR*)CompareValue)) != CompareValue)
&& (((GotValue & RTL_SRWLOCK_MASK) == (RTL_SRWLOCK_SHARED | RTL_SRWLOCK_OWNED)) || (GotValue == 0)));
return ((GotValue & RTL_SRWLOCK_MASK) == (RTL_SRWLOCK_SHARED | RTL_SRWLOCK_OWNED)) || (GotValue == 0);
}
BOOLEAN
NTAPI
RtlTryAcquireSRWLockExclusive(PRTL_SRWLOCK SRWLock)
{
return InterlockedCompareExchangePointer(&SRWLock->Ptr, (ULONG_PTR*)(ULONG_PTR)RTL_SRWLOCK_SHARED, 0) == 0;
}