fix-hibernate

#!/bin/bash

# I use this doc to assist me.
# https://ubuntuhandbook.org/index.php/2021/08/enable-hibernate-ubuntu-21-10/
# Updated with http://askubuntu.com/questions/1240123/ddg#1241902

echo This will first test if your system is able to hibernate.
echo if it works, simply wake your system.
echo if it does not, then the script will setup everything for you.
[[ $(cat /sys/power/state) == "freeze mem disk" ]] && echo "it should be working" || echo "its unlikely to work"
echo -n "ready? [Y/n] "
read answer

if [ "$answer" != "Y" ]; then
  echo Ok bye bye
  exit 0
fi

hibernate_output=$(sudo systemctl hibernate 2>&1)

if [[ $(echo $hibernate_output | grep -o 'not supported$') ]]; then
  system_memory=$(free -m | grep Mem | awk {'print $2'})
  #full_memory=$(grep MemTotal: /proc/meminfo | awk {'print $2'} | rev | cut -c 4- | rev)
  echo "You need a swap file large enough to hold all your system memory ($system_memory MiB)."
  #echo "I will create a file of $full_memory MB."
  swapon --show
  df -h
  echo "Please enter a file name where you want this new swap file to be created. (CTRL-C to cancel.)"
  echo "Entering an existing file will assume this file is the one you want to use and skip creation."
  echo -n "swap fullpath filename: "
  read swapfilepath
  if [ -f $swapfilepath ]; then
    echo "File exist, skipping creation and setting up hibernation."
  else
    echo "Swap file does not exist, proceeding with creation."
    sudo dd if=/dev/zero of=$swapfilepath count=$system_memory bs=1MiB
    sudo chmod 600 $swapfilepath
    sudo mkswap $swapfilepath
    sudo swapon $swapfilepath
    echo "$swapfilepath none swap sw 0 0" | sudo tee -a /etc/fstab
  fi

  blk_info=$(sudo blkid $(df $swapfilepath | tail -n 1 | awk {'print $1'}))
  dev_uuid=$(echo $blk_info | awk {'print $2'} | cut -c 7-42)
  file_offset=$(sudo filefrag -v $swapfilepath | grep "^ *0: " | awk {'print $4'} | rev | cut -c 3- | rev)
  echo "This is your current Grub default options: $(grep GRUB_CMDLINE_LINUX_DEFAULT /etc/default/grub)"
  grub_line="GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash resume=UUID=$dev_uuid resume_offset=$file_offset\""
  echo "I will overwrite it with >>>$grub_line<<<"
  sudo sed -i "s/GRUB_CMDLINE_LINUX_DEFAULT.*/$grub_line/" /etc/default/grub
  sudo apt install --yes pm-utils
  sudo update-grub
  echo "Please reboot your computer before testing again."
  # Maybe optional:
  # Regenerate initramfs:
  echo "RESUME=UUID=$dev_uuid resume_offset=$file_offset" | sudo tee /etc/initramfs-tools/conf.d/resume
  sudo update-initramfs -c -k all
  # Enable Hibernate option in Power-Off Menu:
  polkit_content='
[Re-enable hibernate by default in upower]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes

[Re-enable hibernate by default in logind]
Identity=unix-user:*
Action=org.freedesktop.login1.hibernate;org.freedesktop.login1.handle-hibernate-key;org.freedesktop.login1;org.freedesktop.login1.hibernate-multiple-sessions;org.freedesktop.login1.hibernate-ignore-inhibit
ResultActive=yes
'
  echo "$polkit_content" | sudo tee /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla
  [[ $(cat /sys/power/state) == "freeze mem disk" ]] && echo "it should be working now" || echo "its still unlikely to work"
else
  echo Got unsupported message: $hibernate_output
  echo 42
fi