install-xe-guest-utilities.sh for Gentoo

#!/bin/bash
# Copyright (c) 2011 Pandu E Poluan <pandu@poluan.info>
# Distributed under the terms of the GNU General Public License v2 or newer

# Description: Script to automate installation of Citrix XenServer xe-guest-utilities

INITSCRIPT=/etc/init.d/xe-daemon
APP=$(basename $0)


# Setting up colors & attributes *if* tput exists *and* display supports colors
if which tput &> /dev/null; then
  if (( $(tput colors) >=8 )); then
    c_c="$(tput setaf 6)"   #Cyan
    c_g="$(tput setaf 2)"   #Green
    c_r="$(tput setaf 1)"   #Red
    c_w="$(tput setaf 7)"   #White
    c_b="$(tput setaf 4)"   #Blue
    c_0="$(tput op)"        #Normal
    c__b="$(tput bold)"     #Begin bold
    c__0="$(tput sgr0)"     #End attributes

    c_cb="$c_c$c__b"         #Cyan Bold
    c_gb="$c_g$c__b"         #Green Bold
    c_rb="$c_r$c__b"         #Red Bold
    c_wb="$c_w$c__b"         #White BOld
    c_bb="$c_b$c__b"         #Blue Bold
    c_00="$c__0$c_0"         #Normal without attributes
  fi
fi

# Standardized help
# The coloring variables will not disturb the output even if display does not
# support colors, because they will be null ""
PrintHelp() {
  echo "
${c_wb}${APP}${c_00} - XenServer Guest Utilities Installer

SYNTAX:

    ${c_wb}${APP} ${c_c}PATH ARCH${c_00}

    ${c_cb}PATH${c_00} is either one of:
       1* Device where ${c_gb}xs-tools.iso${c_00} is loaded
       2* Path containing the ${c_rb}.rpm${c_00} files
       3* Path containing the ${c_bb}Linux${c_00} directory containing #2 above

    ${c_cb}ARCH${c_00} is either one of:
       ${c_cb}i386${c_00} if you need the 32-bit variant, or
       ${c_cb}x86_64${c_00} or ${c_cb}amd64${c_00} if you need the 64-bit variant.
       (The latter two are synonyms)

"
}


# First, check if help is requested. If so, emit help, and exit normally.
if [[ "-h" == "$1" || "--help" == "$1" ]] ; then
  PrintHelp
  exit 0
fi

# We need 2 parameters. If the 2nd parameter is null, print help, and exit abnormally
if [[ "" == "$2" ]] ; then
  PrintHelp
  exit 1
fi

# Limit allowable ARCH-es
case $2 in
  i386)
    ARCH=$2
    ;;
  x86_64|x86-64|amd64)
    ARCH=x86_64
    ;;
  *)
    PrintHelp
    exit 1
    ;;
esac

# Check if necessary tools are installed
ExitIfNotMerged() {
  if ! which $1 &> /dev/null; then
    printf "\nCan't find ${c_wb}${1}${c_00}."
    [[ "$2" ]] && printf "\nHave you ${c_cb}emerge ${2}${c_00} yet?\n\n"
    exit 2
  fi
}

ExitIfNotMerged rpm2cpio app-arch/rpm
ExitIfNotMerged cpio     app-arch/cpio

ProgressReport() {
  printf "\n "
  if [[ $1 == 0 ]]; then
    printf "${c_gb}*${c_00} "
  else
    printf "${c_rb}*${c_00} "
  fi
  printf "$2"
}

# Let's process the source first
SRC=$1

# First, check if parameter is a block special file (in which case, we must mount)
if [[ -b $SRC ]]; then
  ProgressReport 0 "Mounting $SRC as /mnt"
  mount $SRC /mnt &> /dev/null
  SRCPATH=/mnt
else
  SRCPATH=$SRC
fi

# If the SRCPATH is not a directory, then abort
# (if $1 is a device, SRCPATH is the mounted path of the device)
if ! [[ -d $SRCPATH ]]; then
  printf "\n${c_bb}$SRCPATH${c_00} is not found. Aborting!\n\n"
  exit 3
fi

# Check that there are 2 .rpm files we need here
ProgressReport 0 "Searching for ${c_wb}$ARCH${c_00} .rpm files"
if (( $(find $SRCPATH -maxdepth 2 -name "xe-guest-utilities-*.$ARCH.rpm" | wc -l) < 2 )); then
    ProgressReport 1 "\nCan't find the needed ${c_rb}.rpm${c_00} files."
    ProgressReport 1 "\nPlease check your parameters.\n\n"
    [[ -b $SRC ]] && umount $SRC
    exit 3
fi

# Save our current directory, so we can exit the work directories
PREVDIR=$(pwd)

for f in $(find $SRCPATH -maxdepth 2 -name "xe-guest-utilities-*.$ARCH.rpm"); do
  TEMPDIR=$(mktemp -d)
  cd $TEMPDIR
  ProgressReport 0 "Extracting $(basename $f)"
  if ! rpm2cpio $f | cpio -id &> /dev/null ; then
    ProgressReport 1 "Error while extracting ${c_rb}${f}${c_00} !!"
    exit 4
  fi
  if [[ $f =~ xenstore ]]; then
    DIRstore=$TEMPDIR
  else
    DIRutils=$TEMPDIR
  fi
done

### First, we process the utilities directory
ProgressReport 0 "Processing xe-guest-utilities"
procdirs=( /etc/udev/rules.d /usr )
for d in ${procdirs[@]}; do
  cp -rn ${DIRutils}${d}/* $d
done

### Second, we process the xenstore directory
ProgressReport 0 "Processing xe-guest-utilities-xenstore"
cp -rn ${DIRstore}/usr/* /usr
ProgressReport 0 "Remaking xenstore symbolic links"
for f in ${DIRstore}/usr/bin/xenstore-* ; do
  bf=$(basename $f)
  rm -f /usr/bin/$bf
  ln -s /usr/bin/xenstore /usr/bin/$bf
done

### Three, we create the proper, OpenRC-compatible initscript
ProgressReport 0 "Creating initscript"
cat - > $INITSCRIPT <<<'#!/sbin/runscript
# Copyright (c) 2011 Pandu E Poluan <pandu@poluan.info>
# Distributed under the terms of the GNU General Public License v2 or newer

description="xe-daemon enables the XenServer hypervisor to interrogate some status of the Gentoo DomU VM"
description_start="Starts the xe-daemon"
description_stop="Stops the xe-daemon"

depend() {
    need localmount
    after bootmisc
}

XE_LINUX_DISTRIBUTION=/usr/sbin/xe-linux-distribution
XE_LINUX_DISTRIBUTION_CACHE=/var/cache/xe-linux-distribution
XE_DAEMON=/usr/sbin/xe-daemon
XE_DAEMON_PIDFILE=/var/run/${SVCNAME}.pid

checkxen() {
    if [ ! -x "${XE_LINUX_DISTRIBUTION}" ] ; then
        eend 1 "${SVCNAME}: Could not find ${XE_LINUX_DISTRIBUTION}"
        return 1
    else
        return 0
    fi
}

checkdom0() {
    if [ -e /proc/xen/capabilities ] && grep -q control_d /proc/xen/capabilities ; then
      ewarn 1 "${SVCNAME}: Not necessary to run this in dom0"
      return 1
    else
      return 0
    fi
}

mountxenfs() {
    local XENFS_RSLT=0
    eindent
    if [ ! -e /proc/xen/xenbus ] ; then
        if [ ! -d /proc/xen ] ; then
            eerror "Could not find /proc/xen directory!"
            eerror "Need a post 2.6.29-rc1 kernel with CONFIG_XEN_COMPAT_XENFS=y and CONFIG_XENFS=y|m"
            XENFS_RSLT=1
        else
            # This is needed post 2.6.29-rc1 when /proc/xen support was pushed upstream as a xen filesystem
            if mount -t xenfs none /proc/xen ; then
                einfo "xenfs mounted on /proc/xen"
            else
                eerror "Failed mounting xenfs on /proc/xen!"
                XENFS_RSLT=1
            fi
        fi
    fi
    eoutdent
    return $XENFS_RSLT
}

start() {
    checkxen || return 1
    checkdom0 || return 1

    ebegin "${SVCNAME} starting..."

    if mountxenfs ; then
      :
    else
      eend 1 "${SVCNAME} not started!"
      return 1
    fi

    eindent

      einfo "Detecting Linux distribution version"
      ${XE_LINUX_DISTRIBUTION} ${XE_LINUX_DISTRIBUTION_CACHE}

      einfo "Daemonizing"
      mkdir -p $(dirname ${XE_DAEMON_PIDFILE})

    eoutdent

    start-stop-daemon --start --exec "${XE_DAEMON}" --background \
        --pidfile "${XE_DAEMON_PIDFILE}" \
        -- -p ${XE_DAEMON_PIDFILE}

    eend $?
}

stop() {
    ebegin "Stopping ${SVCNAME}"
    start-stop-daemon --stop --exec "/usr/sbin/xe-daemon" --pidfile "/var/run/xe-daemon.pid"
    eend $?
}

## End of xe-daemon initscript
'
chmod +x $INITSCRIPT

# Clean up
ProgressReport 0 "Cleaning up"
cd $PREVDIR
rm -rf $DIRutils $DIRstore

# Unmount if it was a device we're reading from
if [[ -b $SRC ]] ; then
  ProgressReport 0 "Unmounting $SRC"
  umount $SRC
fi

printf "\n
   Successfully installed xe-guest-utilities.
   Don't forget to do ${c_cb}rc-update add xe-daemon default${c_00} to ensure that the
   xe-daemon runs on boot.

   After doing the ${c_c}rc-update${c_00} above, you are strongly suggested to reboot.

   After reboot, you can check on xe-daemon's status by entering the following
   command: ${c_cb}pgrep xe-daemon${c_00}
"

exit 0

## End of install-xe-guest-utilities.sh