#!/bin/sh

run_it () {

# Pretty message function
NiceMsg () {
   printf "\033[0;32m$1\033[0m\n"
}

# Version compare function
cver () {
  echo $1 | perl -n \
  -e '@ver = /^([0-9]+)\.([0-9]+)(?:\.([0-9]+))?(?:\.([0-9]+))?/;' \
  -e 'printf "%04s%04s%04s%04s", @ver;'
}

if [ "$(uname -s)" != "Darwin" ] || [ $(cver "$(sw_vers -productVersion)") -le $(cver "10.10") ]; then
    NiceMsg "=> Not intended to run on this platform/version!  Exiting."
    exit 1
fi

NiceMsg "Welcome!  This script will (hopefully) fix your ulimit settings on your Mac..."
echo
NiceMsg "*** If you didn't intend to run this, press Ctrl-C within 10 seconds! ***"
sleep 10

if [ -f /etc/launchd.conf ]; then
  NiceMsg "=> You have an /etc/launchd.conf file, which should be removed."
fi

# Remove lines that shouldn't be in sysctl.conf
if [ -f /etc/sysctl.conf ]; then
  NiceMsg "=> Removing kern.maxfiles* settings which should not be in /etc/sysctl.conf anymore"
  perl -ni -e 'print unless /^kern.maxfiles/' /etc/sysctl.conf
  echo "  => Done!"
fi

NiceMsg "=> Writing new LaunchDaemon property list..."
cat <<EOM > /Library/LaunchDaemons/limit.maxfiles.plist
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
    <dict>
      <key>Label</key>
        <string>limit.maxfiles</string>
      <key>ProgramArguments</key>
        <array>
          <string>launchctl</string>
          <string>limit</string>
          <string>maxfiles</string>
          <string>524288</string>
          <string>524288</string>
        </array>
      <key>RunAtLoad</key>
        <true/>
    </dict>
  </plist>
EOM

NiceMsg "=> Activating new settings immediately..."
launchctl load -w /Library/LaunchDaemons/limit.maxfiles.plist

NiceMsg "Done!  Hopefully you can enjoy your expensive hardware to its full potential now!"
NiceMsg "====> Please close this shell and open a new shell to use the new settings! <===="
trap - EXIT
set +e
}

run_it