After many years of using Linux (and I am not going to be criticizing any specific distribution here) I came to the realization that installing any non trivial thing is a kind of a rite of passage. It’s almost like a ceremony of going to an adulthood. The first time one modprobes psmouse module just to make the touchpad work again after upgrading the system feels like one is not a child anymore. Linux is often a test to sift the weak from the strong, a test if one still has what it takes to use it. All jokes aside, I don’t mind the need to install this or that dependency but sometimes it feels like a maze that you need to navigate your way out of.
Recently I had to move to a new machine after a hardware failure in my previous latop. This meant that I needed to install Desktop Head Unit for Android Auto to work on some of my projects. Google has a nice page describing the installation process but not with all the possible issues. So where should I start?
I’ve used the SDK Manager and downloaded version 1.1 with it. Android Auto Desktop Head Unit Emulator is easy to spot from the Android Studio UI, It took a minute to download. The package was available in the SDK_LOCATION/extras/google/auto/ and according to Googles adivce I switched the executable bit for it with a simple chmod +x ./desktop-head-unit. All is fine!
There is nothing left but to run it.
$ ./desktop-head-unit
./desktop-head-unit: error while loading shared libraries: libSDL2_ttf-2.0.so.0: cannot open shared object file: No such file or directory
Ok, so I was missing libSDL2_ttf-2.0.so on my Ubuntu 20.04 a quick look at the Google instruction revealed that I needed to install a few packages more for this to work:
They were even kind enough to show the command that would install said packages. Running it unfortunately did not go so well.
$ sudo apt-get install libsdl2-2.0-0 libsdl2-ttf-2.0-0 libportaudio2 libpng12-0
(...)
Package libpng12-0 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'libpng12-0' has no installation candidate
Ok, so everything else installed fine, I just need to install this libpng12-0 and it will be fine. So libpng12 is no longer available in the system repositories and archives, all apps should be built with the newer version libpng16 instead. Lucky me! Ubuntu dropped libpng12 with version 16.10 so it is definitely not available on 20.04.
It is not hard to find it, someone was kind enough to prepare a PPA with it.
First adding the PPA:
$ sudo add-apt-repository ppa:linuxuprising/libpng12
libpng12-0 for Ubuntu 20.10, 20.04, 19.10 or 19.04: https://www.linuxuprising.com/2018/05/fix-libpng12-0-missing-in-ubuntu-1804.html
More info: https://launchpad.net/~linuxuprising/+archive/ubuntu/libpng12
Press [ENTER] to continue or Ctrl-c to cancel adding it.
(...)
Fetched 141 kB in 2s (66.6 kB/s)
Reading package lists... Done
Then an update and installation:
$ sudo apt update
(...)
$ sudo apt install libpng12-0
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
libpng12-0
0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/173 kB of archives.
After this operation, 290 kB of additional disk space will be used.
(Reading database ... 273706 files and directories currently installed.)
Preparing to unpack .../libpng12-0_1.2.54-1ubuntu1.1+1~ppa0~focal_amd64.deb ...
Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1.1+1~ppa0~focal) ...
Setting up libpng12-0:amd64 (1.2.54-1ubuntu1.1+1~ppa0~focal) ...
Processing triggers for libc-bin (2.31-0ubuntu9.2) ...
There is nothing left but to run it.
$ ./desktop-head-unit
./desktop-head-unit: error while loading shared libraries: libssl.so.1.0.0: cannot open shared object file: No such file or directory
Ok, a quick look at the list of needed packages for desktop head unit did not specify libssl. It is obvious at this point that I already had a newer version of libssl on my system, the question is where to find the needed one. Luckily enough for it was easy to find.
Now to download and install it.
$ wget http://security.ubuntu.com/ubuntu/pool/main/o/openssl1.0/libssl1.0.0_1.0.2n-1ubuntu5.7_amd64.deb
$ sudo apt install libssl1.0.0_1.0.2n-1ubuntu5.7_amd64.deb
There is nothing left but to run it.
./desktop-head-unit
ALSA lib pcm_dmix.c:1089:(snd_pcm_dmix_open) unable to open slave
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe
ALSA lib pcm.c:2642:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side
ALSA lib pcm_route.c:869:(find_matching_chmap) Found no matching channel map
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pcm_oss.c:377:(_snd_pcm_oss_open) Unknown field port
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_usb_stream.c:486:(_snd_pcm_usb_stream_open) Invalid type for card
ALSA lib pcm_dmix.c:1089:(snd_pcm_dmix_open) unable to open slave
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
Connecting over ADB to localhost:5277...failed.
Failed to start Google Automotive Link.
Ok, finally it works. Works? but there is a glaring failed in the output. Yes that is true but it can be easily fixed (sic!) with a few things:
adb forward tcp:5277 tcp:5277and then there is nothing left but to run desktop head unit again!