#!/bin/bash
#
# script: rc.udev
#
# This is a script to initialize udev, which populates the /dev
# directory with device nodes, scans for devices, loads the
# appropriate kernel modules, and configures the devices.
#
# LimeTech - modified for Unraid OS
# Bergware - modified for Unraid OS, October 2023

# Set the path.
PATH=/sbin:/bin

# run & log functions
. /etc/rc.d/rc.runlog

check_mounted(){
  grep -Eq "^[^[:space:]]+ $1 $2" /proc/mounts
}

mount_devpts(){
  if ! check_mounted /dev/pts devpts; then
    mkdir /dev/pts 2>/dev/null
    mount -n -o mode=0620,gid=5 -t devpts devpts /dev/pts
  fi
}

mount_devshm(){
  if ! check_mounted /dev/shm tmpfs; then
    mkdir /dev/shm 2>/dev/null
    mount /dev/shm
  fi
}

case "$1" in
'start')
  # Sanity check #1, udev requires that the kernel support tmpfs:
  if ! grep -wq tmpfs /proc/filesystems; then
    log "Sorry, but you need tmpfs support in the kernel to use udev."
    log "FATAL: Refusing to run /etc/rc.d/rc.udev."
    exit 1
  fi
  # Sanity check #2, make sure that a 2.6.x kernel is new enough:
  if [[ $(uname -r | cut -f 1,2 -d .) == 2.6 ]]; then
    if [[ $(uname -r | cut -f 3 -d . | sed 's/[^[:digit:]].*//') -lt 32 ]]; then
      log "Sorry, but you need a 2.6.32+ kernel to use this udev."
      log "Your kernel version is only $(uname -r)."
      log "FATAL: Refusing to run /etc/rc.d/rc.udev."
      exit 1
    fi
  fi
  # Sanity check #3, make sure the udev package was not removed.  If udevd
  # is not there, this will also shut off this script to prevent further
  # problems:
  if [[ ! -x /sbin/udevd ]]; then
    chmod 0644 /etc/rc.d/rc.udev
    log "No udevd daemon found."
    log "Turning off udev:  chmod 644 /etc/rc.d/rc.udev"
    log "FATAL:  Refusing to run /etc/rc.d/rc.udev."
    exit 1
  fi
  # Disable hotplug helper since udevd listens to netlink:
  if [[ -e /proc/sys/kernel/hotplug ]]; then
    echo >/proc/sys/kernel/hotplug
  fi
  if grep -qw devtmpfs /proc/filesystems; then
    if ! check_mounted /dev devtmpfs; then
      # umount shm if needed
      check_mounted /dev/shm tmpfs && umount -l /dev/shm
      # Umount pts if needed, we will remount it later:
      check_mounted /dev/pts devpts && umount -l /dev/pts
      # Mount tmpfs on /dev:
      mount -n -t devtmpfs -o size=8M devtmpfs /dev
    fi
  else
    # Mount tmpfs on /dev:
    if ! check_mounted /dev tmpfs; then
      # umount shm if needed
      check_mounted /dev/shm tmpfs && umount -l /dev/shm
      # Umount pts if needed, we will remount it later:
      check_mounted /dev/pts devpts && umount -l /dev/pts
      # Mount tmpfs on /dev:
      # the -n is because we don't want /dev umounted when
      # someone (rc.[06]) calls umount -a
      mount -n -o mode=0755 -t tmpfs -o size=8M tmpfs /dev
    fi
  fi
  # Mount devpts
  mount_devpts
  mount_devshm
  if ! pidof udevd &>/dev/null; then # start udevd
    log "Creating static nodes in /dev."
    run kmod static-nodes -f tmpfiles --output /run/static-nodes
    grep "^d " /run/static-nodes | while read line; do
      mkdir -p -m $(echo $line | cut -f 3 -d ' ') $(echo $line | cut -f 2 -d ' ')
    done
    grep -v "^d " /run/static-nodes | while read line; do
      mknod -m $(echo $line | cut -f 3 -d ' ') \
      $(echo $line | cut -f 2 -d ' ') \
      $(echo $line | cut -b1 ) \
      $(echo $line | cut -f 7 -d ' ' | cut -f 1 -d :) \
      $(echo $line | cut -f 7 -d ' ' | cut -f 2 -d :) 2>/dev/null
    done
    rm -f /run/static-nodes
    # Add any system defined additional device nodes:
    cp --preserve=all --recursive --update /lib/udev/devices/* /dev 2>/dev/null
    # Add any locally defined additional device nodes:
    cp --preserve=all --recursive --update /etc/udev/devices/* /dev 2>/dev/null
    log "Starting udevd..."
    run udevd --daemon
    # Since udev is just now being started we want to use add events:
    log "Triggering udev events..."
    # Call udevtrigger and udevsettle to do the device configuration:
    run udevadm trigger --type=subsystems --action=add
    run udevadm trigger --type=devices --action=add
  else # trigger changes for already running udevd
    # Bergware - set file references
    RAM=/etc/udev/rules.d/70-persistent-net.rules
    ROM=/boot/config/network-rules.cfg
    MAC='ATTR{address}=="\K..:..:..:..:..:..'
    # If the persistent network rules file does not exist, trigger an add event:
    if [[ ! -r $RAM ]]; then
      # Test that we can actually write to the directory first:
      if touch /etc/udev/rules.d/testfile 2>/dev/null; then
        rm -f /etc/udev/rules.d/testfile
        # This should add persistent net rules:
        log "Triggering udev to write persistent rules to /etc/udev/rules.d/"
        run udevadm trigger --type=devices --action=add
        sleep 3
        # Create the files if they don't exist at this point.
        # If a machine does not have a network device or an optical
        # device, we don't want to waste time trying to generate
        # rules at every boot.
        # To force another attempt, delete the file(s).
        touch $RAM
      fi
    fi
    # Bergware - start of code
    if [[ -f $ROM ]]; then
      NEW=$(grep -Po $MAC $RAM | sort)
      # Bergware - set persistent rules of existing interfaces
      grep -B2 "$NEW" $ROM | /usr/bin/fromdos >$RAM
      run udevadm control --reload
      # Bergware - find the unique drivers currently in use by the interface(s)
      DRIVERS=
      for PORT in $(ls --indicator-style=none /sys/class/net | grep -P '^eth\d+$'); do
        DRIVER=$(/usr/sbin/ethtool -i $PORT | grep -Po '^driver: \K\S+')
        [[ $DRIVERS != *$DRIVER* ]] && DRIVERS="$DRIVERS $DRIVER"
      done
      # Bergware - delete existing interfaces and recreate them using the updated udev rules
      modprobe -r $DRIVERS
      modprobe -a $DRIVERS
      # Bergware - check for changes and save them
      if [[ $NEW != $(grep -Po $MAC $ROM | sort) ]]; then
        # Bergware - copy to flash only when more than one interface is present
        [[ $(echo "$NEW" | wc -l) -gt 1 ]] && /usr/bin/todos <$RAM >$ROM || rm -f $ROM
      fi
    else
      # Bergware - remove leading remarks in file
      sed -i '/^# This/,/^$/d' $RAM
      # Bergware - copy to flash only when more than one interface is present
      [[ $(grep -Pc 'NAME="eth\d+"' $RAM) -gt 1 ]] && /usr/bin/todos <$RAM >$ROM || rm -f $ROM
    fi
    # Bergware - end of code
    # Update the hardware database index (/etc/udev/hwdb.bin), if possible:
    if touch /etc/udev/testfile 2>/dev/null; then
      rm -f /etc/udev/testfile
      log "Updating hardware database index..."
      run udevadm hwdb --update
    fi
    # Since udevd is running, most of the time we only need change events:
    log "Triggering udev events..."
    run udevadm trigger --type=subsystems --action=change
    run udevadm trigger --type=devices --action=change
  fi
  run udevadm settle --timeout=120
  ;;
'stop')
  log "Stopping udevd is STRONGLY discouraged and not supported."
  log "If you are sure you want to do this, use 'force-stop' instead."
  ;;
'restart')
  log "Restarting udevd is STRONGLY discouraged and not supported."
  log "If you are sure you want to do this, use 'force-restart' instead."
  ;;
'reload')
  log "Reloading udev rules"
  udevadm control --reload
  ;;
'force-stop')
  log "Stopping udevd"
  udevadm control --exit
  killall udevd 2>/dev/null
  ;;
'force-restart')
  log "Restarting udevd"
  udevadm control --exit
  sleep 3
  udevd --daemon
  ;;
'force-reload')
  log "Updating all available device nodes in /dev"
  udevadm control --reload
  rm -rf /dev/.udev /dev/disk
  cp --preserve=all --recursive --update /lib/udev/devices/* /dev 2>/dev/null
  ;;
*)
  echo "Usage: $BASENAME start|stop|restart|reload|force-stop|force-restart|force-reload"
  exit 1
esac
exit 0