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Rewrite DoWaveStreaming (makes CommitWaveHeaderToKernelDevice redundant).

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Tested with Media Player and NT's Sound Blaster 16 kernel-mode driver on
Windows NT4. Audio buffers play correctly and don't suffer from the
stuttering problem that my previous revision of this code did.


svn path=/trunk/; revision=39669
This commit is contained in:
Andrew Greenwood 2009-02-18 21:26:28 +00:00
parent b25be07add
commit cbac26c676
2 changed files with 91 additions and 3 deletions
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2
reactos/include/reactos/libs/sound/mmebuddy.h
View file

@ -595,7 +595,7 @@ WriteWaveHeader(
wave/streaming.c
*/
MMRESULT
VOID
DoWaveStreaming(
IN PSOUND_DEVICE_INSTANCE SoundDeviceInstance);

92
reactos/lib/drivers/sound/mmebuddy/wave/streaming.c
View file

@ -21,7 +21,7 @@
*/
#define SOUND_KERNEL_BUFFER_COUNT 10
#define SOUND_KERNEL_BUFFER_SIZE 200000
#define SOUND_KERNEL_BUFFER_SIZE 16384
/*
@ -29,13 +29,15 @@
Check if there is streaming to be done, and if so, do it.
*/
MMRESULT
VOID
DoWaveStreaming(
IN PSOUND_DEVICE_INSTANCE SoundDeviceInstance)
{
MMRESULT Result;
PSOUND_DEVICE SoundDevice;
PMMFUNCTION_TABLE FunctionTable;
PWAVEHDR Header;
PWAVEHDR_EXTENSION HeaderExtension;
Result = GetSoundDeviceFromInstance(SoundDeviceInstance, &SoundDevice);
SND_ASSERT( MMSUCCESS(Result) );
@ -45,6 +47,91 @@ DoWaveStreaming(
SND_ASSERT( FunctionTable );
SND_ASSERT( FunctionTable->CommitWaveBuffer );
/* No point in doing anything if no resources available to use */
if ( SoundDeviceInstance->OutstandingBuffers >= SOUND_KERNEL_BUFFER_COUNT )
{
SND_TRACE(L"DoWaveStreaming: No available buffers to stream with - doing nothing\n");
return;
}
/* Is there any work to do? */
Header = SoundDeviceInstance->HeadWaveHeader;
if ( ! Header )
{
SND_TRACE(L"DoWaveStreaming: No work to do - doing nothing\n");
return;
}
while ( ( SoundDeviceInstance->OutstandingBuffers < SOUND_KERNEL_BUFFER_COUNT ) &&
( Header ) )
{
HeaderExtension = (PWAVEHDR_EXTENSION) Header->reserved;
SND_ASSERT( HeaderExtension );
/* Can never be *above* the length */
SND_ASSERT( HeaderExtension->BytesCommitted <= Header->dwBufferLength );
if ( HeaderExtension->BytesCommitted == Header->dwBufferLength )
{
Header = Header->lpNext;
}
else
{
PSOUND_OVERLAPPED Overlap;
LPVOID OffsetPtr;
DWORD BytesRemaining, BytesToCommit;
BOOL OK;
/* Where within the header buffer to stream from */
OffsetPtr = Header->lpData + HeaderExtension->BytesCommitted;
/* How much of this header has not been committed */
BytesRemaining = Header->dwBufferLength - HeaderExtension->BytesCommitted;
/* We can commit anything up to the buffer size limit */
BytesToCommit = BytesRemaining > SOUND_KERNEL_BUFFER_SIZE ?
SOUND_KERNEL_BUFFER_SIZE :
BytesRemaining;
/* Should always have something to commit by this point */
SND_ASSERT( BytesToCommit > 0 );
/* We need a new overlapped info structure for each buffer */
Overlap = AllocateStruct(SOUND_OVERLAPPED);
if ( Overlap )
{
ZeroMemory(Overlap, sizeof(SOUND_OVERLAPPED));
Overlap->SoundDeviceInstance = SoundDeviceInstance;
Overlap->Header = Header;
/* Adjust the commit-related counters */
HeaderExtension->BytesCommitted += BytesToCommit;
++ SoundDeviceInstance->OutstandingBuffers;
OK = MMSUCCESS(FunctionTable->CommitWaveBuffer(SoundDeviceInstance,
OffsetPtr,
BytesToCommit,
Overlap,
CompleteIO));
if ( ! OK )
{
/* Clean-up and try again on the next iteration (is this OK?) */
SND_WARN(L"FAILED\n");
FreeMemory(Overlap);
HeaderExtension->BytesCommitted -= BytesToCommit;
-- SoundDeviceInstance->OutstandingBuffers;
}
}
}
}
#if 0
// HACK
SND_TRACE(L"Calling buffer submit routine\n");
@ -68,6 +155,7 @@ DoWaveStreaming(
}
return Result;
#endif
}