static HRESULT STDCALL MemAllocator_GetBuffer(IMemAllocator * This,
/* [out] */ IMediaSample **ppBuffer,
/* [in] */ REFERENCE_TIME *pStartTime,
/* [in] */ REFERENCE_TIME *pEndTime,
/* [in] */ DWORD dwFlags)
{
MemAllocator* me = (MemAllocator*)This;
CMediaSample* sample;
Debug printf("MemAllocator_ReleaseBuffer(%p) called %d %d\n", This,
avm_list_size(me->used_list), avm_list_size(me->free_list));
if (!me->free_list)
{
Debug printf("No samples available\n");
return E_FAIL;//should block here if no samples are available
}
sample = (CMediaSample*) me->free_list->member;
me->free_list = avm_list_del_head(me->free_list);
me->used_list = avm_list_add_tail(me->used_list, sample);
*ppBuffer = (IMediaSample*) sample;
sample->vt->AddRef((IUnknown*) sample);
if (me->new_pointer)
{
if (me->modified_sample)
me->modified_sample->ResetPointer(me->modified_sample);
sample->SetPointer(sample, me->new_pointer);
me->modified_sample = sample;
me->new_pointer = 0;
}
return 0;
}
//------------------------------------------------------------------------------
// IDecklinkPushSource2 interface
//------------------------------------------------------------------------------
//------------------------------------------------------------------------------
// GetFrameBuffer
// Provide the caller with a free media sample. If there are no free samples,
// all have been delivered downstream, block until one is returned to the free list.
STDMETHODIMP CCustomAllocator::GetFrameBuffer(IMediaSample** ppSample)
{
HRESULT hr = S_OK;
if (ppSample)
{
CAutoLock lck(this);
unsigned char* pBuffer = m_lBuffers.RemoveHead(); // retrieve a frame buffer
if (pBuffer)
{
// attempt to retrieve a free media sample
CMediaSample* pSample = NULL;
for (;;)
{
{ // scope for lock
CAutoLock cObjectLock(this);
/* Check we are committed */
if (!m_bCommitted)
{
return VFW_E_NOT_COMMITTED;
}
pSample = (CMediaSample*)m_lFree.RemoveHead();
if (pSample == NULL)
{
SetWaitingFree();
}
}
if (pSample)
{
// return the sample to the caller
hr = pSample->SetPointer(pBuffer, m_lSize);
*ppSample = pSample;
break;
}
/* If we didn't get a sample then wait for the list to signal */
ASSERT(m_hSemFree);
WaitForSingleObject(m_hSemFree, INFINITE);
}
}
else
{
hr = E_FAIL;
}
}
else
{
hr = E_POINTER;
}
return hr;
}
//------------------------------------------------------------------------------
// Deliver
// Attach the supplied buffer to a free media sample. Add media sample to delivery
// queue so that the streaming thread can deliver the sample downstream. If there
// are no free samples, all have been delivered downstream, block until one is returned
// to the free list. If the streaming thread is blocked, waiting for a sample to
// become available on the delivery queue, signal the thread when a new sample is added.
STDMETHODIMP CCustomAllocator::Deliver(unsigned char* pBuffer)
{
HRESULT hr = S_OK;
if (pBuffer)
{
CMediaSample* pSample = NULL;
for (;;)
{
{ // scope for lock
CAutoLock cObjectLock(this);
/* Check we are committed */
if (!m_bCommitted)
{
return VFW_E_NOT_COMMITTED;
}
pSample = (CMediaSample*)m_lFree.RemoveHead();
if (pSample == NULL)
{
SetWaitingFree();
}
}
if (pSample)
{
hr = pSample->SetPointer(pBuffer, m_lSize);
if (SUCCEEDED(hr))
{
CAutoLock cObjectLock(this);
m_lDeliver.AddTail(pSample);
NotifySample();
DbgLog((LOG_TRACE, DBG_MEM, TEXT("CCustomAllocator::Deliver(): m_lFree: %d m_lDeliver: %d"), m_lFree.GetCount(), m_lDeliver.GetCount()));
}
break;
}
/* If we didn't get a sample then wait for the list to signal */
ASSERT(m_hSemFree);
WaitForSingleObject(m_hSemFree, INFINITE);
}
}
else
{
hr = E_POINTER;
}
return hr;
}