void TimerIrqHandler( void )
{
uint32_t elapsedTime = 0;
if( LowPowerModeEnable == false )
{
if( TimerListHead == NULL )
{
return; // Only necessary when the standard timer is used as a time base
}
}
elapsedTime = TimerGetValue( );
TimerEvent_t* elapsedTimer = NULL;
if( elapsedTime > TimerListHead->Timestamp )
{
TimerListHead->Timestamp = 0;
}
else
{
TimerListHead->Timestamp -= elapsedTime;
}
// save TimerListHead
elapsedTimer = TimerListHead;
// remove all the expired object from the list
while( ( TimerListHead != NULL ) && ( TimerListHead->Timestamp == 0 ) )
{
if( TimerListHead->Next != NULL )
{
TimerListHead = TimerListHead->Next;
}
else
{
TimerListHead = NULL;
}
}
// execute the callbacks of all the expired objects
// this is to avoid potential issues between the callback and the object list
while( ( elapsedTimer != NULL ) && ( elapsedTimer->Timestamp == 0 ) )
{
if( elapsedTimer->Callback != NULL )
{
elapsedTimer->Callback( );
}
elapsedTimer = elapsedTimer->Next;
}
// start the next TimerListHead if it exists
if( TimerListHead != NULL )
{
TimerListHead->IsRunning = true;
TimerSetTimeout( TimerListHead );
}
}
void TimerStart( TimerEvent_t *obj )
{
uint32_t elapsedTime = 0;
uint32_t remainingTime = 0;
__disable_irq( );
if( ( obj == NULL ) || ( TimerExists( obj ) == true ) )
{
__enable_irq( );
return;
}
obj->Timestamp = obj->ReloadValue;
obj->IsRunning = false;
if( TimerListHead == NULL )
{
TimerInsertNewHeadTimer( obj, obj->Timestamp );
}
else
{
if( TimerListHead->IsRunning == true )
{
elapsedTime = TimerGetValue( );
if( elapsedTime > TimerListHead->Timestamp )
{
elapsedTime = TimerListHead->Timestamp; // security but should never occur
}
remainingTime = TimerListHead->Timestamp - elapsedTime;
}
else
{
remainingTime = TimerListHead->Timestamp;
}
if( obj->Timestamp < remainingTime )
{
TimerInsertNewHeadTimer( obj, remainingTime );
}
else
{
TimerInsertTimer( obj, remainingTime );
}
}
__enable_irq( );
}
void TimerStop( TimerEvent_t *obj )
{
__disable_irq( );
uint32_t elapsedTime = 0;
uint32_t remainingTime = 0;
TimerEvent_t* prev = TimerListHead;
TimerEvent_t* cur = TimerListHead;
// List is empty or the Obj to stop does not exist
if( ( TimerListHead == NULL ) || ( obj == NULL ) )
{
return;
}
if( TimerListHead == obj ) // Stop the Head
{
if( TimerListHead->IsRunning == true ) // The head is already running
{
elapsedTime = TimerGetValue( );
if( elapsedTime > obj->Timestamp )
{
elapsedTime = obj->Timestamp;
}
remainingTime = obj->Timestamp - elapsedTime;
if( TimerListHead->Next != NULL )
{
TimerListHead->IsRunning = false;
TimerListHead = TimerListHead->Next;
TimerListHead->Timestamp += remainingTime;
TimerListHead->IsRunning = true;
TimerSetTimeout( TimerListHead );
}
else
{
TimerListHead = NULL;
}
}
else // Stop the head before it is started
{
if( TimerListHead->Next != NULL )
{
remainingTime = obj->Timestamp;
TimerListHead = TimerListHead->Next;
TimerListHead->Timestamp += remainingTime;
}
else
{
TimerListHead = NULL;
}
}
}
else // Stop an object within the list
{
remainingTime = obj->Timestamp;
while( cur != NULL )
{
if( cur == obj )
{
if( cur->Next != NULL )
{
cur = cur->Next;
prev->Next = cur;
cur->Timestamp += remainingTime;
}
else
{
cur = NULL;
prev->Next = cur;
}
break;
}
else
{
prev = cur;
cur = cur->Next;
}
}
}
__enable_irq( );
}
