linphone not able to record SIP calls

[brettpim]

I am running Ubuntu 21.10 on a Thinkpad X1 Tablet. I installed linphone with ```sudo apt install linphone```. I tried recording with no success. I got a desktop notification that the recording was in ```~/linphone/captures``` but the directory was empty. I enabled logging and in the logs I found
```
2022-02-02 20:05:30:805 [linphone/qt] MESSAGE QT: components/call/CallModel.cpp:244: "Start recording call:" CallModel(0x7f8e2800c420)
2022-02-02 20:05:30:805 [linphone/mediastreamer] ERROR Cannot record in mkv format, not supported in this build.
```
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu71
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
DistroRelease: Ubuntu 21.10
InstallationDate: Installed on 2017-06-28 (1683 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
Package: linphone-desktop 4.2.5-3
PackageArchitecture: amd64
ProcVersionSignature: Ubuntu 5.13.0-29.32-generic 5.13.19
Tags: impish
Uname: Linux 5.13.0-29-generic x86_64
UpgradeStatus: Upgraded to impish on 2022-02-03 (3 days ago)
UserGroups: adm cdrom dialout dip lpadmin plugdev sambashare sudo video
_MarkForUpload: True

[lotuspsychje (lotuspsychje)]

Thank you for reporting this bug on Ubuntu!

Please type; apport-collect 1960137 from a terminal to collect relevant
systeminfo and logs into this existing bug, so volunteers can start debug
your issue better, thanks!

[brettpim (brett-h)]

apport information

[brettpim (brett-h)]

apport information

[brettpim (brett-h)]

apport information

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[TheRealSpidermonkey (realspidermonkey)]

First of all, please do excuse if I don't reply to this bug in the right way, this is my first interaction on Launchpad.

As far as I can see, this bug is equivalent to Ubuntu bug #1974163. Both in turn are equivalent to Debian bug #979044 (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=979044) and have recently been fixed. I will describe what's necessary to fix this, and I kindly ask you to evaluate whether a feature freeze exception or a similar measure can still be taken for Ubuntu Kinetic.

Some time ago, Linphone has switched to recording calls in MKV only. However, Linphone uses a modified version of libmatroska, which as of now is not available in Ubuntu. It has recently been added in Debian: https://tracker.debian.org/pkg/bcmatroska2

If this library is not available, the ability to handle MKV is turned off during build configuration. This is why a current Ubuntu-packaged Linphone won't record anything, and it can't play most of its own ringtones either. To close this bug, the following steps are necessary:

1) Add bcmatroska2 to the Ubuntu package repositories. This should be doable as it only links to libc. Should it not be able to still get this package into Kinetic, I can confirm that as a workaround the current version packaged in Debian testing can be used after manual installation.

2) Rebuild mediastreamer2 (-> libmediastreamer11) with an installed libbcmatroska2-dev. This automatically adds MKV handling in the current Kinetic version, without any alterations to the build configuration files.

2a) However, a minimal patch is needed as the file src/utils/mkv_reader.cpp is using std::numeric_limits, for which the GCC version currently available in Kinetic is requiring the limits header. (I. e. add the #include <limits> which upstream has already)

I have validated this re-enables the recording and general MKV handling capabilities. Please consider still adding bcmatroska2 to Kinetic if possible; I can't see any problems arising from this as nothing else can possibly depend on this package.