Re: [Libmtp-discuss] send object/get object property list

[Philip L. <ph...@ov...>]

On Sun, 10 Dec 2017 10:41:25 +0000
Alistair Buxton <a.j...@gm...> wrote:

> On 10 December 2017 at 02:11, Alistair Buxton <a.j...@gm...>
> wrote:
> > On 9 December 2017 at 22:59, Philip Langdale <ph...@ov...>
> > wrote: 
> >> I don't know about how reasonable your device side call trace is
> >> but:
> >>
> >> https://git.gnome.org/browse/gvfs/tree/daemon/gvfsbackendmtp.c?h=gnome-3-26#n2527
> >>
> >> You need to declare the android extension string for gvfsd-mtp to
> >> try and use the
> >> direct I/O extensions.
> >>
> >> --phil  
> >
> > That's the problem then. I didn't declare the extension strings,
> > just implemented the functions. But interestingly, gvfs still uses
> > some of the android extensions - I have seen at least
> > GET_PARTIAL_FILE_64 in my logs after I added it.
> >
> > I will implement those strings tomorrow and report back if it
> > works.  
> 
> Okay, this worked - I added the extension strings and now gvfs is
> calling my stubs. So I need to finish implementing those.

Glad to hear.

> Would I be right in saying the microsoft extensions are the operations
> beginning with 0x98.. and the google ones are the ones beginning with
> 0x95..?
>
> If I don't implement the 0x98.. operations (object properties), is it
> okay to not send the microsoft extension string?

I don't know. I didn't consider if there's a specific namespace there,
but I guess it makes sense.
 
> Finally, where are the google extensions documented? They don't seem
> to be in the MTP spec.
> 

They are not part of the core spec, so would not be documented there. I
never found any documentation for them - I used:

https://github.com/hanwen/go-mtpfs

as my reference as this was written by a Googler who understood how the
extensions worked.

--phil