Snapshot 3.1

#!/system/bin/sh

# Change Log
# 3.1
#  Re-Added memory clear from 2.0
#  Added disabling and re-enabling of multi-cpus
# 3.0
#  Leaving /system processes alone
# 2.0 aka dynamic
#  Dynamically determining which services to stop
# 1.0 Initial hard-coded service list

echo $0

##### md5sum e24d678d9c18c7811e16f4755dfd1e19  /system/sbin/busybox-armv7l

### Make sure 'free' command is in the path, recommend /system/sbin/busybox-armv7l --install -s /system/sbin
which free >/dev/null 2>&1
if [[ $? -ne 0 ]]
then
  echo "Unable to find 'which' and/or 'free' command, install busybox-armv7l
# mount -o rw,remount /system
# mkdir /system/sbin
# download https://busybox.net/downloads/binaries/latest/busybox-armv7l to /system/sbin
# chmod 777 /system/sbin/busybox-armv7l
# /system/sbin/busybox-armv7l --install -s /system/sbin
# rm -f /system/sbin/ps"
  exit 1
fi

### Determine list of init rc scripts to reference when looking to pair a process name with a service name
init_rc_list=`ls /init*rc  | grep -v goldfish | tr '\n' ' '`
service_restart_list=""
abort=0

### Determine which services and processes need to be stopped for /extdata and /data to happily umount
for blocking_pid in `fuser -m /extdata /data | sort | uniq`
do
  ### Find the name and parent pid of the blocking pid
  comm=`cat /proc/${blocking_pid}/comm`
  ppid=`cat /proc/${blocking_pid}/stat | awk '{print $4}'`

  ### If the parent pid is another process, set the blocking pid to the parent, the children will stop when the parent stops
  if [[ $ppid -gt 1 ]]
  then
    #echo -n "PARENT ppid = [${ppid}] "
    blocking_pid=${ppid}
    comm=`cat /proc/${blocking_pid}/comm`
  fi

  ### Add service and process names to variables for us to work with later.
  if [[ "${comm}" == "sh" ]]
  then
    echo "There is an open shell using something in /extdata and/or /data... aborting."
    abort=1
  elif [[ "${comm}" == "zygote" ]]
  then
    ### Only add zygote to the list once
    if [[ "$zygote_stopped" == "" ]]
    then
      echo "Adding [zygote] to the list of services to stop"
      service_restart_list=" zygote ${service_restart_list} "
      zygote_stopped=yes
    fi
  elif [[ "${comm}" == "keystore" ]]
  then
    echo "Ignoring keystore, it will be handled by pioneer /sbin/andsnap"
  elif [[ "${comm}" != "" ]]
  then
    echo -n "blocking_pid = [${blocking_pid}] comm = [${comm}] "
    service_name=`grep "^service.*\/${comm}" ${init_rc_list} | awk '{print $2}'`
    if [[ "${service_name}" != "" ]]
    then
      echo "${service_restart_list}" | grep -q " ${service_name} "
      if [[ $? -eq 0 ]]
      then
        echo "Service [${service_name}] has already been dealt with"
      else
        echo "Adding [${service_name}] to the list of services to stop"
        service_restart_list=" ${service_name} ${service_restart_list} "
      fi
    else
      echo "No match for service, killing [${service_name}]"
      killall_list=" ${killall_list} ${comm} "
    fi
  fi
done

echo "service_restart_list = [${service_restart_list}]"

[ $abort -ne 0 ] && exit 1

echo "No changes have been made yet, Ctrl-C to abort within 10 seconds"
for i in `seq 1 10`
do
  echo -n '.'
  sleep 1
done
echo "Continuing on..."

echo "Stopping Services"
for service in ${service_restart_list}
do
  echo "Stopping ${service}"
  stop ${service}
done
echo "Done Stopping Services"

for rogue_process in ${killall_list}
do
  echo "Killing Rogue Process: [${rogue_process}]"
  killall ${rogue_process}
done

multi_cpus=`find /sys/devices/system/cpu/cpu[1-9] -name online 2>/dev/null`
if [[ "${multi_cpus}" == "" ]]
then
  echo "Single CPU, continuing..."
else
  for cpu_online in ${multi_cpus}
  do
    echo "Disabling [${cpu_online}]"
    echo 0 > ${cpu_online}
  done
fi

echo "Sleeping for 10 seconds to let system end processes"
sleep 10

echo "Zero out the memory for a small clean snapshot"
head -n2 /proc/meminfo
sync && echo 3 > /proc/sys/vm/drop_caches && echo ""
memfree=$(free -m | awk '/^Mem/ {print $4-32}')
echo "memfree=[${memfree}]"
if [ $memfree -gt 0 ]; then
        dd if=/dev/zero of=/dev/null bs=${memfree}M count=1
fi
head -n2 /proc/meminfo

sync
sleep 10
sync
/sbin/andsnap $*

if [[ "${multi_cpus}" == "" ]]
then
  echo "Single CPU, continuing..."
else
  for cpu_online in ${multi_cpus}
  do
    echo "Re-enabling [${cpu_online}]"
    echo 1 > ${cpu_online}
  done
fi

echo "Re-Starting Services"
for service in ${service_restart_list}
do
  echo "Starting ${service}"
  start ${service}
done

echo "Done!"