snap install of vlc doesn't have correct permission

[Kim Tyler]

A snap installation of vlc will not allow vlc to play TV. A repo installation of vlc works as expected.
When run from command line, get the following messages:-
--------------snap version------------------
user@host:~$ /snap/bin/vlc Desktop/vlc_playlist.xspf
VLC media player 3.0.8 Vetinari (revision 3.0.8-0-gf350b6b)
[00000000007c7400] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
Qt: Session management error: None of the authentication protocols specified are supported
[00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
[00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
[00007f9a88008f20] dtv stream error: cannot access DVR: Operation not permitted
[00007f9a88001ab0] dtv stream error: cannot access DVR: Operation not permitted
[00007f9ab4000b20] dtv stream error: cannot access DVR: Operation not permitted
QObject::~QObject: Timers cannot be stopped from another thread

--------------repo version-----------------
user@host:~$ /usr/bin/vlc Desktop/vlc_playlist.xspf
VLC media player 3.0.8 Vetinari (revision 3.0.8-0-gf350b6b5a7)
[000055bfea101570] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
[00007f9a44009d30] main decoder error: buffer deadlock prevented
libva info: VA-API version 1.1.0
libva info: va_getDriverName() returns -1
libva error: va_getDriverName() failed with unknown libva error,driver_name=(null)
[00007f9a94002b30] glconv_vaapi_x11 gl error: vaInitialize: unknown libva error
libva info: VA-API version 1.1.0
libva info: va_getDriverName() returns 0
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so
libva info: Found init function __vaDriverInit_1_1
libva info: va_openDriver() returns 0
[00007f9a44009d30] avcodec decoder: Using Intel i965 driver for Intel(R) Haswell - 2.1.0 for hardware decoding

---------------------end of messages-------------

It seems that snap installations do not see the same file permission as the repo version.

1----------------lsb_release -rd

Description: Ubuntu 18.04.4 LTS
Release: 18.04

2a---------------apt-cache policy vlc
vlc:
  Installed: 3.0.8-0ubuntu18.04.1
  Candidate: 3.0.8-0ubuntu18.04.1
  Version table:
 *** 3.0.8-0ubuntu18.04.1 500
        500 http://ftp.iinet.net.au/pub/ubuntu bionic-updates/universe amd64 Packages
        500 http://ftp.iinet.net.au/pub/ubuntu bionic-security/universe amd64 Packages
        100 /var/lib/dpkg/status
     3.0.1-3build1 500
        500 http://ftp.iinet.net.au/pub/ubuntu bionic/universe amd64 Packages

2b--------------snap info vlc
name: vlc
summary: The ultimate media player
publisher: VideoLAN✓
store-url: https://snapcraft.io/vlc
contact: https://www.videolan.org/support/
license: GPL-2.0+
description: |
  VLC is the VideoLAN project's media player.

  Completely open source and privacy-friendly, it plays every multimedia file and streams.

  It notably plays MKV, MP4, MPEG, MPEG-2, MPEG-4, DivX, MOV, WMV, QuickTime, WebM, FLAC, MP3,
  Ogg/Vorbis files, BluRays, DVDs, VCDs, podcasts, and multimedia streams from various network
  sources. It supports subtitles, closed captions and is translated in numerous languages.
snap-id: RT9mcUhVsRYrDLG8qnvGiy26NKvv6Qkd
channels:
  latest/stable: 3.0.8 2019-12-19 (1397) 212MB -
  latest/candidate: 3.0.8 2019-12-16 (1397) 212MB -
  latest/beta: 3.0.8-469-g1525d52452 2020-04-08 (1589) 298MB -
  latest/edge: 4.0.0-dev-11620-ga93072befb 2020-04-06 (1585) 339MB -
3------------expected outcome
snap vlc should work the same as the repo version of vlc, ie display the dvb-t channels. Instead, it fails with the above messages
4----------what happens
Repo version works just fine. Snap version fails with permission errors.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: snapd 2.42.1+18.04
ProcVersionSignature: Ubuntu 4.15.0-88202002241620.0+mediatree+hauppauge-generic 4.15.18
Uname: Linux 4.15.0-88202002241620-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.9-0ubuntu7.14
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Thu Apr 9 12:24:16 2020
InstallationDate: Installed on 2018-05-08 (701 days ago)
InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
SourcePackage: snapd
UpgradeStatus: No upgrade log present (probably fresh install)

[Maciej Borzecki (maciek-borzecki)]

```
[00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
[00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
```

You probably need to allow vlc to access the dvb devices. Can you run `snap connect vlc:dvb` command and check whether it works?

[Kim Tyler (ktyler)]

Hi,

Yes, it works.  Thanks.

I obviously need to do a course on the ins and outs of snap. There
appears to be a lot of stuff to be configured than I'm used to.

Cheers for that,

Kim

On 15/5/20 3:18 am, Maciej Borzecki wrote:
> ```
> [00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
> [00007f9a84000bb0] dtv stream error: cannot access DVR: Operation not permitted
> ```
>
> You probably need to allow vlc to access the dvb devices. Can you run
> `snap connect vlc:dvb` command and check whether it works?
>
> ** Changed in: snapd (Ubuntu)
> Status: New => Incomplete
>

[Maciej Borzecki (maciek-borzecki)]

FWIW there should be a button which you can click in the snap-store. Sadly there does not seem to be one for the `dvb` interface.

[Kim Tyler (ktyler)]

Of course there is a button after you do the manual connection, but I
take your point.

Thanks again.

On 15/5/20 8:45 pm, Maciej Borzecki wrote:
> FWIW there should be a button which you can click in the snap-store.
> Sadly there does not seem to be one for the `dvb` interface.
>
> ** Also affects: snap-store
> Importance: Undecided
> Status: New
>

[Maciej Borzecki (maciek-borzecki)]

Double checked with snap-store from beta channel. The button is there, but it seems off.

When I connected the interface, the UI button is correctly showing on state. Now, I tried disconnecting the interface, which was correctly reported in `snap connections vlc`. However, after restarting snap-store, it's still shown as on.

[Kim Tyler (ktyler)]

Never mind, my problem is solved, although there seems to be some
tidying up to be done.

Thanks again,

Kim

On 15/5/20 9:47 pm, Maciej Borzecki wrote:
> Double checked with snap-store from beta channel. The button is there,
> but it seems off.
>
> When I connected the interface, the UI button is correctly showing on
> state. Now, I tried disconnecting the interface, which was correctly
> reported in `snap connections vlc`. However, after restarting snap-
> store, it's still shown as on.
>