[wdmaudiodev] Re: Data Event in AVStream
- From: "Sam Tertzakian" <sam@xxxxxxxxxxx>
- To: <wdmaudiodev@xxxxxxxxxxxxx>
- Date: Sun, 20 Nov 2005 15:02:23 -0800
Hi,
I have resolved this problem.
The correct way to get the data is in step 3 should be:
KSQUERYBUFFER QueryBuffer;
DWORD Dword;
Event.Flags = KSEVENT_TYPE_QUERYBUFFER;
QueryBuffer.Event = Event;
QueryBuffer.EventData = &EventData.EventData;
QueryBuffer.Reserved = 0;
BytesReturned = 0x0;
hr = m_pControl->KsEvent(
(PKSEVENT)&QueryBuffer,
sizeof( QueryBuffer ),
&Dword,
sizeof (Dword),
&BytesReturned
);
Essentially, the parameters of KsEvent() should be renamed to (inputbuffer,
inputbuffersize, outputbuffer, outputbuffersize). The it matches the call as
if made using KS_IOCTL_*.
I think MSFT should update the docs.unless I am missing something, it is not
intuitive.
_____
From: wdmaudiodev-bounce@xxxxxxxxxxxxx
[mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] On Behalf Of Sam Tertzakian
Sent: Thursday, November 17, 2005 2:09 PM
To: wdmaudiodev@xxxxxxxxxxxxx
Subject: [wdmaudiodev] Data Event in AVStream
Hi,
I am trying to use KSEVENT to get a "data event" from an AVStream driver
(not using KS_IOCTL_* directly).
By "data event", I mean, that the user mode program registers for event
notification and when the underlying AVStream driver signals the event, it
also sends data in a buffer.
The user mode program is able to receive notification of the event. But, it
is unable to get the associated data. Here is what I have:
In Kernel Mode:
1. Define the event:
DEFINE_KSEVENT_ITEM
(
KSEVENT_XXXX, // Id
sizeof( KSEVENTDATA ) + sizeof( ULONG ), // DataInput (ULONG is
data to send)
0, // ExtraEntryData
NULL, // AddHandler
NULL, // RemoveHandler
NULL // SupportHandler
)
2. Signal the event:
ULONG Data=0x12345678;
KsFilterGenerateEvents(
pFilter,
&KSEVENTSETID_XXXX,
KSEVENT_XXXX,
Sizeof( ULONG ),
&Data,
NULL,
NULL
);
In User Mode:
1. Register for the event:
typedef struct {
KSEVENTDATA EventData;
ULONG ExtraData; // where data should go
} EVENTDATAEX, *PEVENTDATAEX;
HANDLE EventHandle;
KSEVENT Event;
EVENTDATAEX EventData;
EventHandle = CreateEvent( NULL, FALSE, FALSE, NULL );
Event.Set = KSEVENTSETID_XXXX;
Event.Id = KSEVENT_XXXX;
Event.Flags = KSEVENT_TYPE_ENABLEBUFFERED;
EventData.EventData.NotificationType = KSEVENTF_EVENT_HANDLE;
EventData.EventData.EventHandle.Event = EventHandle;
EventData.EventData.EventHandle.Reserved [0] = 0;
EventData.EventData.EventHandle.Reserved [1] = 0;
EventData.ExtraData = 0xAAAAAAAA;
// Note: target data should go right after EventData.
hr = m_pControl->KsEvent(
&Event,
sizeof (Event),
&EventData.EventData,
sizeof (EventData.EventData) + sizeof( ULONG
),
&BytesReturned
);
Hr = O_OK. If the size is not the sum in the 4th parameter, I get an error,
so I know that so far I am good.
2. Wait for event:
EventRet = WaitForSingleObject(
EventHandle,
INFINITE
);
if ( EventRet == WAIT_OBJECT_0) {
3. Try to get data:
Here I have tried several ways. I am putting one of them here:
Event.Flags = KSEVENT_TYPE_QUERYBUFFER;
BytesReturned = 0x0;
hr = m_pControl->KsEvent(
&Event,
sizeof(Event),
&EventData.EventData,
sizeof (EventData.EventData) + sizeof( ULONG ),
&BytesReturned
);
Or:
KSQUERYBUFFER QueryBuffer;
Event.Flags = KSEVENT_TYPE_QUERYBUFFER;
QueryBuffer.Event = Event;
QueryBuffer.EventData = &EventData.EventData;
QueryBuffer.Reserved = 0;
BytesReturned = 0x0;
hr = m_pControl->KsEvent(
&Event,
sizeof(Event),
&QueryBuffer,
sizeof( QueryBuffer ) + sizeof( ULONG ),
&BytesReturned
);
I have also verified that the data is not where it should be when the event
is signaled. I have tried not using EVENTBUFFERED and ENABLE instead but
there is no difference.
4. But I always get the error:
Hr = 0x800706F8 (The supplied user buffer is not valid for the requested
operation.)
Does anybody see what I am dong wrong? Is it possible that AVStream does not
support "Data Events"?
Thank you for your time.
Other related posts:
