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|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
//
#include "common.h"
#include "corhost.h"
#include "synch.h"
void CLREventBase::CreateAutoEvent (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
SO_TOLERANT;
// disallow creation of Crst before EE starts
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
PRECONDITION((!IsOSEvent()));
}
CONTRACTL_END;
SetAutoEvent();
{
HANDLE h = UnsafeCreateEvent(NULL,FALSE,bInitialState,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
m_handle = h;
}
}
BOOL CLREventBase::CreateAutoEventNoThrow (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
// disallow creation of Crst before EE starts
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
PRECONDITION((!IsOSEvent()));
}
CONTRACTL_END;
EX_TRY
{
CreateAutoEvent(bInitialState);
}
EX_CATCH
{
}
EX_END_CATCH(SwallowAllExceptions);
return IsValid();
}
void CLREventBase::CreateManualEvent (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
SO_TOLERANT;
// disallow creation of Crst before EE starts
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
PRECONDITION((!IsOSEvent()));
}
CONTRACTL_END;
{
HANDLE h = UnsafeCreateEvent(NULL,TRUE,bInitialState,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
m_handle = h;
}
}
BOOL CLREventBase::CreateManualEventNoThrow (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
// disallow creation of Crst before EE starts
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
PRECONDITION((!IsOSEvent()));
}
CONTRACTL_END;
EX_TRY
{
CreateManualEvent(bInitialState);
}
EX_CATCH
{
}
EX_END_CATCH(SwallowAllExceptions);
return IsValid();
}
void CLREventBase::CreateMonitorEvent(SIZE_T Cookie)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
// disallow creation of Crst before EE starts
PRECONDITION((g_fEEStarted));
PRECONDITION((GetThread() != NULL));
PRECONDITION((!IsOSEvent()));
}
CONTRACTL_END;
// thread-safe SetAutoEvent
FastInterlockOr(&m_dwFlags, CLREVENT_FLAGS_AUTO_EVENT);
{
HANDLE h = UnsafeCreateEvent(NULL,FALSE,FALSE,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
if (FastInterlockCompareExchangePointer(&m_handle,
h,
INVALID_HANDLE_VALUE) != INVALID_HANDLE_VALUE)
{
// We lost the race
CloseHandle(h);
}
}
// thread-safe SetInDeadlockDetection
FastInterlockOr(&m_dwFlags, CLREVENT_FLAGS_IN_DEADLOCK_DETECTION);
for (;;)
{
LONG oldFlags = m_dwFlags;
if (oldFlags & CLREVENT_FLAGS_MONITOREVENT_ALLOCATED)
{
// Other thread has set the flag already. Nothing left for us to do.
break;
}
LONG newFlags = oldFlags | CLREVENT_FLAGS_MONITOREVENT_ALLOCATED;
if (FastInterlockCompareExchange((LONG*)&m_dwFlags, newFlags, oldFlags) != oldFlags)
{
// We lost the race
continue;
}
// Because we set the allocated bit, we are the ones to do the signalling
if (oldFlags & CLREVENT_FLAGS_MONITOREVENT_SIGNALLED)
{
// We got the honour to signal the event
Set();
}
break;
}
}
void CLREventBase::SetMonitorEvent()
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
}
CONTRACTL_END;
// SetMonitorEvent is robust against initialization races. It is possible to
// call CLREvent::SetMonitorEvent on event that has not been initialialized yet by CreateMonitorEvent.
// CreateMonitorEvent will signal the event once it is created if it happens.
for (;;)
{
LONG oldFlags = m_dwFlags;
if (oldFlags & CLREVENT_FLAGS_MONITOREVENT_ALLOCATED)
{
// Event has been allocated already. Use the regular codepath.
Set();
break;
}
LONG newFlags = oldFlags | CLREVENT_FLAGS_MONITOREVENT_SIGNALLED;
if (FastInterlockCompareExchange((LONG*)&m_dwFlags, newFlags, oldFlags) != oldFlags)
{
// We lost the race
continue;
}
break;
}
}
void CLREventBase::CreateOSAutoEvent (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
// disallow creation of Crst before EE starts
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
//_ASSERTE (g_fEEStarted);
SetOSEvent();
SetAutoEvent();
HANDLE h = UnsafeCreateEvent(NULL,FALSE,bInitialState,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
m_handle = h;
}
BOOL CLREventBase::CreateOSAutoEventNoThrow (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
// disallow creation of Crst before EE starts
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
EX_TRY
{
CreateOSAutoEvent(bInitialState);
}
EX_CATCH
{
}
EX_END_CATCH(SwallowAllExceptions);
return IsValid();
}
void CLREventBase::CreateOSManualEvent (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
// disallow creation of Crst before EE starts
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
// Can not assert here. ASP.Net uses our Threadpool before EE is started.
//_ASSERTE (g_fEEStarted);
SetOSEvent();
HANDLE h = UnsafeCreateEvent(NULL,TRUE,bInitialState,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
m_handle = h;
}
BOOL CLREventBase::CreateOSManualEventNoThrow (BOOL bInitialState // If TRUE, initial state is signalled
)
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
// disallow creation of Crst before EE starts
PRECONDITION((m_handle == INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
EX_TRY
{
CreateOSManualEvent(bInitialState);
}
EX_CATCH
{
}
EX_END_CATCH(SwallowAllExceptions);
return IsValid();
}
void CLREventBase::CloseEvent()
{
CONTRACTL
{
NOTHROW;
if (IsInDeadlockDetection()) {GC_TRIGGERS;} else {GC_NOTRIGGER;}
SO_TOLERANT;
}
CONTRACTL_END;
GCX_MAYBE_PREEMP(IsInDeadlockDetection() && IsValid());
_ASSERTE(Thread::Debug_AllowCallout());
if (m_handle != INVALID_HANDLE_VALUE) {
{
CloseHandle(m_handle);
}
m_handle = INVALID_HANDLE_VALUE;
}
m_dwFlags = 0;
}
BOOL CLREventBase::Set()
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION((m_handle != INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
_ASSERTE(Thread::Debug_AllowCallout());
{
return UnsafeSetEvent(m_handle);
}
}
BOOL CLREventBase::Reset()
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION((m_handle != INVALID_HANDLE_VALUE));
}
CONTRACTL_END;
_ASSERTE(Thread::Debug_AllowCallout());
// We do not allow Reset on AutoEvent
_ASSERTE (!IsAutoEvent() ||
!"Can not call Reset on AutoEvent");
{
return UnsafeResetEvent(m_handle);
}
}
static DWORD CLREventWaitHelper2(HANDLE handle, DWORD dwMilliseconds, BOOL alertable)
{
STATIC_CONTRACT_THROWS;
STATIC_CONTRACT_SO_TOLERANT;
return WaitForSingleObjectEx(handle,dwMilliseconds,alertable);
}
static DWORD CLREventWaitHelper(HANDLE handle, DWORD dwMilliseconds, BOOL alertable)
{
STATIC_CONTRACT_NOTHROW;
STATIC_CONTRACT_SO_TOLERANT;
struct Param
{
HANDLE handle;
DWORD dwMilliseconds;
BOOL alertable;
DWORD result;
} param;
param.handle = handle;
param.dwMilliseconds = dwMilliseconds;
param.alertable = alertable;
param.result = WAIT_FAILED;
// Can not use EX_TRY/CATCH. EX_CATCH toggles GC mode. This function is called
// through RareDisablePreemptiveGC. EX_CATCH breaks profiler callback.
PAL_TRY(Param *, pParam, ¶m)
{
// Need to move to another helper (cannot have SEH and C++ destructors
// on automatic variables in one function)
pParam->result = CLREventWaitHelper2(pParam->handle, pParam->dwMilliseconds, pParam->alertable);
}
PAL_EXCEPT (EXCEPTION_EXECUTE_HANDLER)
{
param.result = WAIT_FAILED;
}
PAL_ENDTRY;
return param.result;
}
DWORD CLREventBase::Wait(DWORD dwMilliseconds, BOOL alertable, PendingSync *syncState)
{
WRAPPER_NO_CONTRACT;
return WaitEx(dwMilliseconds, alertable?WaitMode_Alertable:WaitMode_None,syncState);
}
DWORD CLREventBase::WaitEx(DWORD dwMilliseconds, WaitMode mode, PendingSync *syncState)
{
BOOL alertable = (mode & WaitMode_Alertable)!=0;
CONTRACTL
{
if (alertable)
{
THROWS; // Thread::DoAppropriateWait can throw
}
else
{
NOTHROW;
}
if (GetThread())
{
if (alertable)
GC_TRIGGERS;
else
GC_NOTRIGGER;
}
else
{
DISABLED(GC_TRIGGERS);
}
SO_TOLERANT;
PRECONDITION(m_handle != INVALID_HANDLE_VALUE); // Handle has to be valid
}
CONTRACTL_END;
_ASSERTE(Thread::Debug_AllowCallout());
Thread * pThread = GetThread();
#ifdef _DEBUG
// If a CLREvent is OS event only, we can not wait for the event on a managed thread
if (IsOSEvent())
_ASSERTE (pThread == NULL);
#endif
_ASSERTE((pThread != NULL) || !g_fEEStarted || dbgOnly_IsSpecialEEThread());
{
if (pThread && alertable) {
DWORD dwRet = WAIT_FAILED;
BEGIN_SO_INTOLERANT_CODE_NOTHROW (pThread, return WAIT_FAILED;);
dwRet = pThread->DoAppropriateWait(1, &m_handle, FALSE, dwMilliseconds,
mode,
syncState);
END_SO_INTOLERANT_CODE;
return dwRet;
}
else {
_ASSERTE (syncState == NULL);
return CLREventWaitHelper(m_handle,dwMilliseconds,alertable);
}
}
}
void CLRSemaphore::Create (DWORD dwInitial, DWORD dwMax)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION(m_handle == INVALID_HANDLE_VALUE);
}
CONTRACTL_END;
{
HANDLE h = UnsafeCreateSemaphore(NULL,dwInitial,dwMax,NULL);
if (h == NULL) {
ThrowOutOfMemory();
}
m_handle = h;
}
}
void CLRSemaphore::Close()
{
LIMITED_METHOD_CONTRACT;
if (m_handle != INVALID_HANDLE_VALUE) {
CloseHandle(m_handle);
m_handle = INVALID_HANDLE_VALUE;
}
}
BOOL CLRSemaphore::Release(LONG lReleaseCount, LONG *lpPreviousCount)
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION(m_handle != INVALID_HANDLE_VALUE);
}
CONTRACTL_END;
{
return ::UnsafeReleaseSemaphore(m_handle, lReleaseCount, lpPreviousCount);
}
}
DWORD CLRSemaphore::Wait(DWORD dwMilliseconds, BOOL alertable)
{
CONTRACTL
{
if (GetThread() && alertable)
{
THROWS; // Thread::DoAppropriateWait can throw
}
else
{
NOTHROW;
}
if (GetThread())
{
if (alertable)
GC_TRIGGERS;
else
GC_NOTRIGGER;
}
else
{
DISABLED(GC_TRIGGERS);
}
SO_TOLERANT;
PRECONDITION(m_handle != INVALID_HANDLE_VALUE); // Invalid to have invalid handle
}
CONTRACTL_END;
Thread *pThread = GetThread();
_ASSERTE (pThread || !g_fEEStarted || dbgOnly_IsSpecialEEThread());
{
// TODO wwl: if alertable is FALSE, do we support a host to break a deadlock?
// Currently we can not call through DoAppropriateWait because of CannotThrowComplusException.
// We should re-consider this after our code is exception safe.
if (pThread && alertable) {
return pThread->DoAppropriateWait(1, &m_handle, FALSE, dwMilliseconds,
alertable?WaitMode_Alertable:WaitMode_None,
NULL);
}
else {
DWORD result = WAIT_FAILED;
EX_TRY
{
result = WaitForSingleObjectEx(m_handle,dwMilliseconds,alertable);
}
EX_CATCH
{
result = WAIT_FAILED;
}
EX_END_CATCH(SwallowAllExceptions);
return result;
}
}
}
void CLRMutex::Create(LPSECURITY_ATTRIBUTES lpMutexAttributes, BOOL bInitialOwner, LPCTSTR lpName)
{
CONTRACTL
{
THROWS;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION(m_handle == INVALID_HANDLE_VALUE && m_handle != NULL);
}
CONTRACTL_END;
m_handle = WszCreateMutex(lpMutexAttributes,bInitialOwner,lpName);
if (m_handle == NULL)
{
ThrowOutOfMemory();
}
}
void CLRMutex::Close()
{
LIMITED_METHOD_CONTRACT;
if (m_handle != INVALID_HANDLE_VALUE)
{
CloseHandle(m_handle);
m_handle = INVALID_HANDLE_VALUE;
}
}
BOOL CLRMutex::Release()
{
CONTRACTL
{
NOTHROW;
GC_NOTRIGGER;
SO_TOLERANT;
PRECONDITION(m_handle != INVALID_HANDLE_VALUE && m_handle != NULL);
}
CONTRACTL_END;
BOOL fRet = ReleaseMutex(m_handle);
if (fRet)
{
EE_LOCK_RELEASED(this);
}
return fRet;
}
DWORD CLRMutex::Wait(DWORD dwMilliseconds, BOOL bAlertable)
{
CONTRACTL {
NOTHROW;
GC_NOTRIGGER;
CAN_TAKE_LOCK;
PRECONDITION(m_handle != INVALID_HANDLE_VALUE && m_handle != NULL);
}
CONTRACTL_END;
DWORD fRet = WaitForSingleObjectEx(m_handle, dwMilliseconds, bAlertable);
if (fRet == WAIT_OBJECT_0)
{
EE_LOCK_TAKEN(this);
}
return fRet;
}
|