[PATCH 1/5] winegstreamer: Implement IMFMediaSource::GetCharacteristics.

[Zebediah Figura]

On 11/2/20 11:00 AM, Derek Lesho wrote:
> On 11/2/20 10:47 AM, Nikolay Sivov wrote:
> 
>> On 11/2/20 7:26 PM, Derek Lesho wrote:
>>> Signed-off-by: Derek Lesho <dlesho at codeweavers.com>
>>> ---
>>>   dlls/winegstreamer/media_source.c | 6 ++++--
>>>   1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/dlls/winegstreamer/media_source.c
>>> b/dlls/winegstreamer/media_source.c
>>> index dbc656a24da..913b1cc9e93 100644
>>> --- a/dlls/winegstreamer/media_source.c
>>> +++ b/dlls/winegstreamer/media_source.c
>>> @@ -1032,12 +1032,14 @@ static HRESULT WINAPI
>>> media_source_GetCharacteristics(IMFMediaSource *iface, DWO
>>>   {
>>>       struct media_source *source = impl_from_IMFMediaSource(iface);
>>>   -    FIXME("(%p)->(%p): stub\n", source, characteristics);
>>> +    TRACE("(%p)->(%p)\n", source, characteristics);
>>>         if (source->state == SOURCE_SHUTDOWN)
>>>           return MF_E_SHUTDOWN;
>>>   -    return E_NOTIMPL;
>>> +    *characteristics = MFMEDIASOURCE_CAN_SEEK;
>>> +
>>> +    return S_OK;
>>>   }
>>>     static HRESULT WINAPI
>>> media_source_CreatePresentationDescriptor(IMFMediaSource *iface,
>>> IMFPresentationDescriptor **descriptor)
>> I think if the choice is between 0 and CAN_SEEK, it should consider
>> MFBYTESTREAM_IS_SEEKABLE. Unless of course if winegstreamer code
>> currently won't work for non-seekable bytestreams at all.
>>
> Since we are now using typefind for the input because Zebediah wanted a
> generic source, it seems that the SetCurrentPosition is used after
> typefind figures out what type of data the input is.  So if the absence
> of MFBYTESTREAM_IS_SEEKABLE means SetCurrentPosition doesn't work, then
> yeah, I don't think the current code would work with such a bytestream
> at all.  On the other hand, if MFBYTESTREAM_IS_SEEKABLE only indicates
> whether IMFByteStream::Seek is functional, then we should be fine as we
> never use that method. The documentation on this isn't clear.
> 

It seems fair to assume that MFBYTESTREAM_IS_SEEKABLE also covers
SetCurrentPosition(). I'd assume that flag covers all random access, and
would be clear for e.g. a TCP byte stream.

[Incidentally, although this is an implementation detail, typefind does
support streams which can't seek, although perhaps not very well, and it
seems to need push mode.]

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: OpenPGP digital signature
URL: <http://www.winehq.org/pipermail/wine-devel/attachments/20201102/c8d72655/attachment.sig>