Version 0.2.5 crashs with SEGV if invoked by systemd

[kerel-fs]

ogn-rf and ogn-decode crashes with SEGV or exits when stdin is redirected from /dev/null.
This redirection is done by default by systemd for simple services.

Steps to repoduce

Download and install rtlsdr-ogn-0.2.5.ARM, then execute it with

./ogn-rf /etc/rtlsdr-ogn/site.conf < /dev/null

Alternatively, there is an ansible role to reproduces the issue with systemd involved: ogn-node

Initial log (systemd involved): http://paste.debian.net/hidden/b0f487a3/
Minimal failing scenario:

ogn@collin:/opt/rtlsdr-ogn-0.2.5 $ ./ogn-rf /etc/rtlsdr-ogn/site.conf < /dev/null 
HTTP_Server.Exec() ... Start
HTTP_Server.Exec() ... Listening on port 8080
Found Rafael Micro R820T tuner
Exact sample rate is: 1000000.026491 Hz
RTLSDR::Open(0,868300000,1000000) => Generic RTL2832U OEM,  868.300 MHz, 1.000 Msps
RTLSDR::Gain[29] =  +0.0  +0.9  +1.4  +2.7  +3.7  +7.7  +8.7 +12.5 +14.4 +15.7 +16.6 +19.7 +20.7 +22.9 +25.4 +28.0 +29.7 +32.8 +33.8 +36.4 +37.2 +38.6 +40.2 +42.1 +43.4 +43.9 +44.5 +48.0 +49.6 [dB]
RF_Acq.Exec() ... Half time slot
ogn@collin:/opt/rtlsdr-ogn-0.2.5 $

[kerel-fs]

I propose to add a command-line argument allowing ogn-rf and ogn-decode to run non-interactive, perhaps even as a proper daemon (--daemon/-d: Runs process in the background).

[kerel-fs]

Possible fix

Detect whether stdin is a terminal or a pipe and only try to read from stdin if it's a terminal.
see also: SO: Detect if stdin is a terminal or pipe in C/C++/Qt?

[csindle]

Also affects version 0.2.6.

[saedelman]

This works for me. I use tty20 for ogn-rf and tty21 for ogn-decode.

[Service]
Type=simple
WorkingDirectory=/home/pi/rtlsdr-ogn
ExecStart=/home/pi/rtlsdr-ogn/ogn-rf /home/pi/rtlsdr-ogn/ogn.conf
KillMode=process
StandardInput=tty-force
TTYVHangup=yes
TTYPath=/dev/tty20
TTYReset=yes
Restart=always
RestartSec=10
KillSignal=SIGKILL

[rvt]

Perhaps late in the game, from docker I can run it with:

setsid sh -c 'exec ./ogn-rf Station.conf <> /dev/tty20'