dw-start.sh

#!/usr/bin/env bash

# Why not simply "#!/bin/bash" ?

# For OpenBSD, the bash location is /usr/local/bin/bash.
# By using env here, bash is found based on the user's $PATH.
# I hope this does not break some other operating system.


# Run this from crontab periodically to start up
# Dire Wolf automatically.

# See User Guide for more discussion.
# For release 1.4 it is section 5.7 "Automatic Start Up After Reboot"
# but it could change in the future as more information is added.


# Versioning (this file, not direwolf version)
#-----------
# v1.3 - KI6ZHD - added variable support for direwolf binary location
# v1.2 - KI6ZHD - support different versions of VNC
# v1.1 - KI6ZHD - expanded version to support running on text-only displays with 
#        auto support; log placement change
# v1.0 - WB2OSZ - original version for Xwindow displays only



#How are you running Direwolf : within a GUI (Xwindows / VNC) or CLI mode
#
#  AUTO mode is design to try starting direwolf with GUI support and then
#    if no GUI environment is available, it reverts to CLI support with screen
#
#  GUI mode is suited for users with the machine running LXDE/Gnome/KDE or VNC
#    which auto-logs on (sitting at a login prompt won't work)
#
#  CLI mode is suited for say a Raspberry Pi running the Jessie LITE version
#      where it will run from the CLI w/o requiring Xwindows - uses screen

RUNMODE=AUTO

# Location of the direwolf binary.  Depends on $PATH as shown.
# change this if you want to use some other specific location.
# e.g.  DIREWOLF="/usr/local/bin/direwolf"

DIREWOLF="direwolf"


#Direwolf start up command :: Uncomment only one of the examples.
#
# 1. For normal operation as TNC, digipeater, IGate, etc.
#    Print audio statistics each 100 seconds for troubleshooting.
#    Change this command to however you wish to start Direwolf

DWCMD="$DIREWOLF -a 100"

# 2. FX.25 Forward Error Correction (FEC) will allow your signal to
#    go farther under poor radio conditions.  Add "-X 1" to the command line.

#DWCMD="$DIREWOLF -a 100 -X 1"

#---------------------------------------------------------------
#
# 3. Alternative for running with SDR receiver.
#    Piping one application into another makes it a little more complicated.
#    We need to use bash for the | to be recognized.

#DWCMD="bash -c 'rtl_fm -f 144.39M - | direwolf -c sdr.conf -r 24000 -D 1 -'"


#Where will logs go - needs to be writable by non-root users
LOGFILE=/var/tmp/dw-start.log


#-------------------------------------
# Main functions of the script
#-------------------------------------

#Status variables
SUCCESS=0

function CLI {
   SCREEN=`which screen`
   if [ $? -ne 0 ]; then
      echo -e "Error: screen is not installed but is required for CLI mode.  Aborting"
      exit 1
   fi

   echo "Direwolf in CLI mode start up"
   echo "Direwolf in CLI mode start up" >> $LOGFILE

   # Screen commands
   #  -d m :: starts the command in detached mode
   #  -S   :: name the session
   $SCREEN -d -m -S direwolf $DWCMD >> $LOGFILE
   SUCCESS=1

   $SCREEN -list direwolf
   $SCREEN -list direwolf >> $LOGFILE

   echo "-----------------------"
   echo "-----------------------" >> $LOGFILE
}

function GUI {
   # In this case
   # In my case, the Raspberry Pi is not connected to a monitor.
   # I access it remotely using VNC as described here:
   # http://learn.adafruit.com/adafruit-raspberry-pi-lesson-7-remote-control-with-vnc
   #
   # If VNC server is running, use its display number.
   # Otherwise default to :0 (the Xwindows on the HDMI display)
   #
   export DISPLAY=":0"

   #Reviewing for RealVNC sessions (stock in Raspbian Pixel)
   if [ -n "`ps -ef | grep vncserver-x11-serviced | grep -v grep`" ]; then
      sleep 0.1
      echo -e "\nRealVNC found - defaults to connecting to the :0 root window"
     elif [ -n "`ps -ef | grep Xtightvnc | grep -v grep`" ]; then
      #Reviewing for TightVNC sessions
      echo -e "\nTightVNC found - defaults to connecting to the :1 root window"
      v=`ps -ef | grep Xtightvnc | grep -v grep`
      d=`echo "$v" | sed 's/.*tightvnc *\(:[0-9]\).*/\1/'`
      export DISPLAY="$d"
   fi

   echo "Direwolf in GUI mode start up"
   echo "Direwolf in GUI mode start up" >> $LOGFILE
   echo "DISPLAY=$DISPLAY" 
   echo "DISPLAY=$DISPLAY" >> $LOGFILE

   # 
   # Auto adjust the startup for your particular environment:  gnome-terminal, xterm, etc.
   #

   if [ -x /usr/bin/lxterminal ]; then
      /usr/bin/lxterminal -t "Dire Wolf" -e "$DWCMD" &
      SUCCESS=1
     elif [ -x /usr/bin/xterm ]; then
      /usr/bin/xterm -bg white -fg black -e "$DWCMD" &
      SUCCESS=1
     elif [ -x /usr/bin/x-terminal-emulator ]; then
      /usr/bin/x-terminal-emulator -e "$DWCMD" &
      SUCCESS=1
     else
      echo "Did not find an X terminal emulator.  Reverting to CLI mode"
      SUCCESS=0
   fi
   echo "-----------------------"
   echo "-----------------------" >> $LOGFILE
}

# -----------------------------------------------------------
# Main Script start
# -----------------------------------------------------------

# When running from cron, we have a very minimal environment
# including PATH=/usr/bin:/bin.
#
export PATH=/usr/local/bin:$PATH

#Log the start of the script run and re-run
date >> $LOGFILE

# First wait a little while in case we just rebooted
# and the desktop hasn't started up yet.
#
sleep 30


#
# Nothing to do if Direwolf is already running.
#

a=`ps ax | grep direwolf | grep -vi -e bash -e screen -e grep | awk '{print $1}'`
if [ -n "$a" ] 
then
  #date >> /tmp/dw-start.log
  #echo "Direwolf already running." >> $LOGFILE
  exit
fi

# Main execution of the script

if [ $RUNMODE == "AUTO" ];then 
   GUI
   if [ $SUCCESS -eq 0 ]; then
      CLI
   fi
  elif [ $RUNMODE == "GUI" ];then
   GUI
  elif [ $RUNMODE == "CLI" ];then
   CLI
  else
   echo -e "ERROR: illegal run mode given.  Giving up"
   exit 1
fi