diff options
| author | J M Rossy <[email protected]> | 2015-07-29 15:40:09 -0700 |
|---|---|---|
| committer | J M Rossy <[email protected]> | 2015-07-29 16:34:40 -0700 |
| commit | 5d61a4a79a1e96dc5d9af1e5e712c84507307544 (patch) | |
| tree | 49ed270893578cd18758b74ffcca16dc7ab948d6 /avscamera/sys/Timer.cpp | |
| parent | 5d41613e26e147d2300c786bb2b34cb4b4067a25 (diff) | |
Samples update for public Windows 10 release
Fix #2 Enabling WPP Recorder in Sensors Samples causes errors
Fix #4 Add back fixed KMDOD sample
Add new BarcodeScanner sample in pos folder
Add new MagneticStripeReader sample in pos folder
Add new SynpaticsTouch sample in input folder
Add new Power Engine Plugin sample in pofx folder
Add new DeviceMft sample in avstream folder
Add new AvsCamera sample in root
Add new SimBatt sample in root
Add other pre-existing samples not yet released for Win10
Diffstat (limited to 'avscamera/sys/Timer.cpp')
| -rw-r--r-- | avscamera/sys/Timer.cpp | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/avscamera/sys/Timer.cpp b/avscamera/sys/Timer.cpp new file mode 100644 index 00000000..5345a361 --- /dev/null +++ b/avscamera/sys/Timer.cpp @@ -0,0 +1,172 @@ +/************************************************************************** + + A/V Stream Camera Sample + + Copyright (c) 2014, Microsoft Corporation. + + File: + + timer.cpp + + Abstract: + + Contains the implementation of a KTimer and KPassiveTimer. + + KTimer wraps a kernel timer object. KPassiveTimer uses a passive + callback through a KWorkItem. + + History: + + created 5/30/2014 + +**************************************************************************/ + +#include "Common.h" + +KTimer:: +KTimer( TIMER_TYPE type ) + : m_Period(0) + , m_Context(NULL) + , m_Callback(NULL) +{ + KeInitializeTimerEx( &m_Timer,type ) ; + KeInitializeDpc( &m_Dpc, KTimer::DpcThunk, this ) ; +} + +KTimer:: +~KTimer() +{ + Cancel(); +} + +// +// Cancels the timer and ensures no DPC is executing. +// +BOOLEAN +KTimer:: +Cancel() +{ + // Clear the timer and dequeue the DPC. + if( !Reset() ) + { + // If the item wasn't found, flush all the DPC queues. + KeFlushQueuedDpcs() ; + + // Return false because we lost the race. + return FALSE; + } + return TRUE; +} + +// +// Support for waitable class +// +PVOID +KTimer:: +GetDispatchObject() +{ + return &m_Timer; +} + +// +// Dpc Thunking function for KeSetTimerEx +// +_Function_class_(KDEFERRED_ROUTINE) +VOID +KTimer:: +DpcThunk( + _In_ PKDPC /*Dpc*/, + _Inout_opt_ PVOID DeferredContext, + _Inout_opt_ PVOID /*Arg1*/, + _Inout_opt_ PVOID /*Arg2*/ +) +{ + KTimer *pKTimer = (KTimer *) DeferredContext ; + pKTimer->Func() ; +} + +// +// Function invoked when a timer expires +// +// IRQL <= DISPATCH_LEVEL +// +void +KTimer:: +Func() +{ + if( m_Callback ) + { + m_Callback( m_Context ) ; + } +} + +// +// Dtor +// +// Calls Cancel() here to clean up. +// +// Note: KTimer will also call Cancel(), but it will invoke KTimer::Cancel(). +// Since KPassiveTimer::Cancel() first calls KTimer::Cancel() this second +// call is redudant; but preventing it would probably require an explicit +// call to Cancel() before destruction. This way you can just delete +// timers when they are no longer needed, but it make take a bit longer. +// +KPassiveTimer:: +~KPassiveTimer() +{ + Cancel(); +} + +// +// Function invoked when a timer expires +// +// IRQL == DISPATCH_LEVEL +// +void +KPassiveTimer:: +Func() +{ + if( m_Callback ) + { + // Start the work item. If it fails, there's not much we can do since + // it can only fail if the owner of this timer is trying to cancel it. + m_WorkItem.Start(); + } +} + +VOID +KPassiveTimer:: +WorkThunk( + _In_ PDEVICE_OBJECT DeviceObject, + _In_opt_ PVOID Context +) +{ + UNREFERENCED_PARAMETER(DeviceObject); + + if( Context ) + { + ((KPassiveTimer *) Context)->KTimer::Func(); + } +} + +// +// Cancels the timer +// +BOOLEAN +KPassiveTimer:: +Cancel() +{ + // Kill the timer. + if( !KTimer::Cancel() ) + { + // Wait until the work item is idle. + m_WorkItem.Wait(); + + // Reset the WorkItem so we can use it again. + m_WorkItem.Reset(); + + return FALSE; + } + return TRUE; +} + |
