#!/bin/bash
# file: database_h
#
# Copyright (C) 2015 Ubuntu Kylin
#
# Author: Min Chen <minchen@ubuntukylin.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Library Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Library Public License for more details.
#

my_dir=$(dirname "$0")

. $my_dir/common_h
. $my_dir/metadata_h
. $my_dir/epoch_h

db_image_prefix=
db_image_size=
db_order=
db_snap_id=
db_snap_image_size=
found=0

#init osd_data and get all objects path
function gen_database()
{
  local func="gen_database"
  rm -rf $database/*
  rm -rf $images
  rm -rf $raw
  mkdir -p $database
  local host=
  local data_path=

  trap 'echo $func failed; exit;' INT HUP
  while read line
  do
    {
      host=`echo $line|awk '{print $1}'`
      data_path=`echo $line|awk '{print $2}'`
      if [ "$host"x = ""x ] || [ "$data_path"x = ""x ];then
 	continue
      fi
      local cmds="find $data_path/current -type f"
      ssh $ssh_option $host $cmds > $database/$host
    } &
  done < $osd_host_path
  wait
  echo "$func: finish"
}

# collect hobjects from database 
# and choose the object whose epoch is latest
# then, sort the objects by their offsets in image 
function gather_hobject_common()
{
  func="gather_hobject_common"

  trap 'echo $func failed; exit;' INT HUP
  if [ $# -lt 2 ];then
    echo "$func: parameters: <pool_id> <image_prefix> [<snap_id>]"  
    exit
  fi

  local pool_id=$1
  local image_prefix=$2
  pool_id=$(($pool_id))
  local hex_pool_id=`printf "%x" $pool_id`
  # NOSNAP = uint64(-2)
  local snap_id=`printf "%u" -2`
  local hex_snap_id="head"
  local psuffix=
  local fsuffix="_head"
  if [ $# = 3 ];then
    snap_id=$(($3))
    hex_snap_id=`printf "%x" $snap_id`
    psuffix="_"$snap_id
    fsuffix="_"$snap_id
  fi
  local underline_image_prefix=`convert_underline $image_prefix`
  local dump_image_prefix=`dump_backslash $underline_image_prefix`
  local ddump_image_prefix=`dump_dump_backslash $underline_image_prefix`
  local images_raw_dir=$rbd_image/raw
  local image_hobjects_dir=$images/pool_$pool_id/$image_prefix
  # $images/raw/$image_prefix"_head"
  local image_hobjects_raw=$images_raw_dir/$image_prefix"$fsuffix"
  # $images/$image_prefix/$image_prefix"_head"
  local image_hobjects_stable=$image_hobjects_dir/$image_prefix"$fsuffix"

  if [ ! -e $images_raw_dir ];then
    mkdir -p $images_raw_dir
  fi
  if [ ! -e $image_hobjects_dir ];then
  local image_metadata=$images_meta/$image_name_in
    mkdir -p $image_hobjects_dir
  fi

  pushd $database >/dev/null
  local  pattern="\.[0-9a-f]+__"$hex_snap_id"_[0-9A-F]{8}__"$hex_pool_id
  >$image_hobjects_raw
  grep -r -E $dump_image_prefix""$pattern * >$image_hobjects_raw
  if [ ! -s $image_hobjects_raw ];then
    echo "$func: image snap [ $image_prefix"$psuffix" ] is empty"
    return 1 #no data available
  fi
  popd >/dev/null

  local offset_dir_temp=$images_raw_dir/$image_prefix"$fsuffix""_dir_temp"
  rm -rf $offset_dir_temp
  mkdir -p $offset_dir_temp

  echo "gather hobjects from database: snapid=$snap_id ..."

  # format: ceph2:/var/lib/ceph/osd/ceph-1/current/2.d3_head/rb.0.1293.6b8b4567.000000000002__head_FB425CD3__2
  local tmp_image=$offset_dir_temp/tmpimage.$$$$
  >$tmp_image
  cat $image_hobjects_raw | 
  awk -F ':' '
  BEGIN {
    pg_coll="'$pg_coll'"
    tmp_image="'$tmp_image'"
    osd_host_mapping="'$osd_host_mapping'"
    snapid="'$snap_id'"
  }{ 
      # $2 = /var/lib/ceph/osd/ceph-1/current/2.d3_head/rb.0.1293.6b8b4567.000000000002__head_FB425CD3__2

      split($2, arr1, "/current/");   # {/var/lib/ceph/osd/ceph-1/, 2.d3_head/rb.0.1293.6b8b4567.000000000002__head_FB425CD3__2}
      split(arr1[2], arr2, "/");     # {2.d3_head, rb.0.1293.6b8b4567.000000000002__head_FB425CD3__2} 
      split(arr2[1], arr3, "_head"); # {2.d3,} 

      hobject=$2;
      data_path=arr1[1];
      gsub(/\\u/, "\\\\\\\\u", hobject); # dump backslash to delay escape (\ -> \\)
      "awk \"\\$1 == \\\""$1"\\\" {print \\$2}\" "osd_host_mapping" | head -n 1" | getline node
      pgid = arr3[1];

      len=length(arr2);
      offset_hobject=arr2[len]             # rb.0.1293.6b8b4567.000000000002__head_FB425CD3__2
      split(offset_hobject, offarr1, "."); # {rb, 0, 1293, 6b8b4567, 000000000002__head_FB425CD3__2}
      len1=length(offarr1) 
      offset_p=offarr1[len1]               # 000000000002__head_FB425CD3__2
      split(offset_p, offarr2, "__");      # {000000000002, head_FB425CD3, 2}
      offset=offarr2[1];                   # 000000000002

      system("echo -n \""node" "pgid" "hobject" "offset" "snapid" \" >>"tmp_image);
      #system("echo -n \""node" "pgid" "hobject" "offset" "snapid" \"");
      #print node" "pgid" "hobject" "offset" "snapid
      
      # find pg_epoch from pg_coll database
      system("awk  \"\\$1 == \\\""node"\\\" && \\$2 == \\\""pgid"\\\" && \\$4 == \\\""data_path"\\\" {print \\$3}\" "pg_coll" >>"tmp_image);
      #system("awk  \"\\$1 == \\\""node"\\\" && \\$2 == \\\""pgid"\\\" && \\$4 == \\\""data_path"\\\" {print \\$3}\" "pg_coll);
  }'

  local sort_image=$offset_dir_temp/sortimage.$$$$
  >$sort_image
  sort -t ' ' -k 4.1,4 -k 6.1nr -k 1.1,1 $tmp_image >$sort_image
  sort -t ' ' -k 4.1,4 -u $sort_image > $image_hobjects_stable
  
  #rm -rf $offset_dir_temp
  return 0
}

function gather_hobject_nosnap()
{
  gather_hobject_common $1 $2
}

function gather_hobject_snap()
{
  gather_hobject_common $1 $2 $3
}

# select the max pg_epoch item of the same $field
# if no same $field, choose the first 
# format : "node $field pg_epoch"
function choose_epoch()
{
  cat $1|sort -t ' ' -k 3.1,3nr -k 2.1,2n |head -n 1;
}

# lookup image info , after scatter_node_jobs & gather_node_infos
function lookup_image()
{
  local func="lookup_image"
  if [ $# -lt 2 ];then
    echo "$func: parameters error <pool_id> <image_name> [<snap_name>]"
  fi
  local pool_id=$1
  local image_name=$2
  local snap_name=$3
  pool_id=$((pool_id))
  echo -e "$func: pool_id = $pool_id\timage_name = $image_name\tsnap_name = $snap_name"
  if [ $pool_id -lt 0 ];then
    echo "$func: pool_id must great than zero"
    exit
  fi
  local hex_pool_id=`printf "%x" $pool_id`
  input_image $image_name
  local node=
  local item=/tmp/item.$$$$
  local img_name=`dump_backslash $image_name`

  local image_format=0
  local image_id_hobject=
  local image_header_hobject=
  local result=/tmp/tmp_result.$$$$
  local res1=/tmp/tmp_res1.$$$$
  local res2=/tmp/tmp_res2.$$$$
  local data_path=

  # image format v1
  {
    cat $image_coll_v1|grep -E "/$img_name\.rbd__head_[0-9A-F]{8}__$hex_pool_id" >$res1
    if [ -s $res1 ];then
      echo -n "$func: rbd_header_hobject = "
      choose_epoch $res1| tee $item
      #choose_epoch $res1 > $item
      
      if [ -e $item ];then
        node=`cat $item|awk '{print $1}'`
        image_header_hobject=`cat $item|awk '{print $2}'`
        if [ "$node"x = ""x ];then
    	  echo "$func: v1 node is NULL"
 	  exit
	fi
	if [ "$image_header_hobject"x = ""x ];then
	  echo "$func: v1 image_header_hobject is NULL"
	  exit
  	fi
        rm -f $item
      fi

      image_format=1
      echo -e "image_name:\t$image_name_in"
      echo -e "image_format:\t$image_format"
      data_path=`echo $image_header_hobject|awk -F "/current" '{print $1}'`
 
      >$result
      cmds="bash $job_path/osd_job do_image_metadata_v1 $data_path `dump_backslash $image_header_hobject` $snap_name" 
      ssh $ssh_option $node $cmds | tee $result
    fi
  }

  # image format v2
  {
    cat $image_coll_v2|grep -E "/rbd\\\\uid\."$img_name"__head_[0-9A-F]{8}__$hex_pool_id" >$res2
    if [ -s $res2 ];then
      echo -n "$func: rbd_id_hobject = "
      choose_epoch $res2 | tee $item
      #choose_epoch $res2 > $item

      if [ -e $item ];then
        node=`cat $item|awk '{print $1}'`
        image_id_hobject=`cat $item|awk '{print $2}'`
        if [ "$node"x = ""x ];then
    	  echo "$func: v2 node is NULL(to get image_id_hobject)"
 	  exit
	fi
	if [ "$image_id_hobject"x = ""x ];then
	  echo "$func: v2 image_id_hobject is NULL"
	  exit
  	fi
        rm -f $item
      fi

      check_osd_process $node
      image_format=2
      
      local tid=/tmp/image_id.$$$$
      data_path=`echo $image_id_hobject|awk -F "/current" '{print $1}'`
      >$tid
      cmds="bash $job_path/osd_job do_image_id $data_path `dump_backslash $image_id_hobject`" 
      ssh $ssh_option $node $cmds > $tid

      local image_id=`cat $tid`
      rm -f $tid

      #get image_header_hobject
      pushd $database >/dev/null
      local pattern="header\."$image_id"__head_[0-9A-F]{8}__$hex_pool_id"
      local tcoll=/tmp/tmp_image_head_coll.$$$$

      # hostname(by command hostname) in $pg_coll  maybe different from hostname in tcoll(input by user) 
      # t_host:        hostname read from config file ($tcoll)
      # t_host_remote: $(hostname) on osd node ($pg_coll)
      grep -r -E $pattern * >$tcoll
      popd >/dev/null

      local t_host=(`cat $tcoll|awk -F ":" '{print $1}'`)
      local t_pgid=(`cat $tcoll|awk -F ":" '{print $2}'|sed -n 's/.*\/\([0-9a-fA-F]\+\.[0-9a-fA-F]\+\)_head\/.*/\1/p'`)
      local t_hobject=(`cat $tcoll|awk -F ":" '{print $2}'`)
      local t_data_path=(`cat $tcoll|awk -F ":" '{split($2, arr, "/current/"); print arr[1];}'`)
      rm -f $tcoll
      declare -a t_host_remote

      #if there is no failed pg migration, number of t_host is replica num
      #replica num : 3, 4, 5 ...
      local t_hostname=/tmp/t_hostname.$$$$
      for ((i=0; i<${#t_host[*]}; i++))
      do
	ssh $ssh_option ${t_host[$i]} "hostname" >$t_hostname
	if [ $? != 0 ];then
	  echo "$func: ${t_host[$i]} get host_remote failed"
	  exit
	fi
        t_host_remote[$i]=`cat $t_hostname`	
      done
      rm -f $t_hostname

      local t_item=/tmp/tmp_item.$$$$
      local tmp_item=/tmp/tmp_tmp_item.$$$$
      
      >$tmp_item
      for ((i=0; i<${#t_host_remote[*]}; i++ ))
      do
	local node=${t_host_remote[$i]}
	local pgid=${t_pgid[$i]}
	awk '$1 == "'"$node"'" && $2 == "'"$pgid"'" {print}' $pg_coll >>$tmp_item
      done

      # t_item: <remote_hostname> <pgid> <epoch> <data_path>
      sort -u $tmp_item >$t_item
      rm -f $tmp_item

      local entry=`choose_epoch $t_item` #t_host_remote
      rm -f $t_item

      node=`echo $entry|awk '{print $1}'`
      data_path=`echo $entry|awk '{print $4}'`
      if [ "$node"x = ""x ];then
        echo "$func: v2 node is NULL (to get image_header_hobject)"
        exit
      fi

      for ((i=0; i<${#t_host_remote[*]}; i++))
      do
	if [ "${t_host_remote[$i]}"x = "$node"x ] && [ "${t_data_path[$i]}"x = "$data_path"x ];then
	  image_header_hobject=${t_hobject[$i]}
	  break
	fi
      done
      
      if [ "$image_id_hobject"x = ""x ];then
        echo "$func: v2 image_header_hobject is NULL"
        exit
      fi

      check_osd_process $node
     
      echo "$func: rbd_header_hobject = $node $image_header_hobject"
      echo -e "image_name:\t$image_name_in"
      echo -e "image_format:\t$image_format"

      #data_path=`echo $image_header_hobject|awk -F "/current" '{print $1}'`
      >$result
      cmds="bash $job_path/osd_job do_image_metadata_v2 $data_path $image_id `dump_backslash $image_header_hobject` $snap_name" 
      ssh $ssh_option $node $cmds | tee $result
    fi
  }

  if [ ! -s $result ];then
    echo "$func: $image_name_in not exists" 
    exit
  fi
  
  # to assign value to global variable
  db_image_prefix=`cat $result|awk '/^(object_prefix|block_name):/{print $2}'`
  if [ "$db_image_prefix"x = ""x ];then
    echo "$func: image_prefix is NULL"
    exit
  fi

  db_image_size=`cat $result|awk '/^image_size:/{print $2}'`
  db_order=`cat $result|awk '/^order:/{print $2}'`
  if [ "$snap_name"x != ""x ];then
    db_snap_id=`cat $result|awk '/^snapshot:/{print $2}'`
    if [ "$db_snap_id"x = ""x ];then
      echo "$func: $image_name_in@$snap_name NOT EXISTS"
      exit
    fi
    db_snap_image_size=`cat $result|awk '/^snapshot:/{print $4}'`
  else
    #save snaplist
    local image_snaplist=$images/pool_$pool_id/$image_name_in/@snaplist
    local image_dir=$images/pool_$pool_id/$image_name_in
    if [ ! -e $image_dir ];then
      mkdir -p $image_dir
    fi
    cat $result|awk '/^snapshot:/{print $2" "$3" "$4}' >$image_snaplist
  fi
  found=1
  rm -f $result
}

function list_images()
{
   echo "=============== format =============="
   echo "format: <pool_id>/<image_name>"
   echo "================ v1: ================"
   #sed -n 's/\(.*\)\/\(.*\)\.rbd__\(.*\)/\2/p' $image_coll_v1|sort -u|sed -e 's/\\u/_/g'
   sed -n 's/.*\/\(.*\)\.rbd__head_[0-9A-F]\{8\}__\([0-9a-f]\+\).*/\2 \1/p' $image_coll_v1|sort -u|awk '{print strtonum("0x"$1)"/"$2;}'|sed -e 's/\\u/_/g'
   echo "================ v2: ================"
   #sed -n 's/\(.*\)\/rbd\\uid.\(.*\)__\(head.*\)/\2/p' $image_coll_v2|sort -u|sed 's/\\u/_/g'
   sed -n 's/.*\/rbd\\uid.\(.*\)__head_[0-9A-F]\{8\}__\([0-9a-f]\+\).*/\2 \1/p' $image_coll_v2|sort -u|awk '{print strtonum("0x"$1)"/"$2}'|sed 's/\\u/_/g'
}

# lookup image metadata
# and 
# collect hobjects of image with the latest pg epoch
function discover_image_nosnap()
{
  local func="discover_image_nosnap"
  echo "$func ..."
  local pool_id=$1
  local image_name=$2
  pool_id=$(($pool_id))
  lookup_image $pool_id $image_name # assign $image_prefix
  gather_hobject_nosnap $pool_id $db_image_prefix 
  if [ $? -ne 0 ];then
    exit
  fi
  local image_hobjects_stable_nosnap=$images/pool_$pool_id/$db_image_prefix/$db_image_prefix"_head"
  local image_hobjects_dir=$images/pool_$pool_id/$image_name_in
  if [ ! -e $image_hobjects_dir ];then
    mkdir -p $image_hobjects_dir
  fi
  # mv image_prefix to image_name
  mv $image_hobjects_stable_nosnap $image_hobjects_dir/$image_name_in
  rm -rf $images/pool_$pool_id/$db_image_prefix
}

# get the offset snapid object 
# if there is no object, choose the smallest snapid which is greater than current snapid
function get_object_clone()
{
  local func="get_object_clone"
  if [ $# -lt 4 ];then
    exit
  fi

  local object_offset_string=$1
  local snapid=$2
  local snaplist_path=$3
  local snapset_output_dir=$4

  # snapid in desc
  local snap_coll_arr=(`
  cat $snaplist_path|awk '{ if ($1 >= '"$snapid"') print "'"$snapset_output_dir"'/@"$1}'`) 

  local hex_snapid=`printf "%x" $snapid`
  pushd $snapset_output_dir >/dev/null
  # get object with the smallest snapid greater than current snapid
  awk '$4 == "'"$object_offset_string"'" && $5 >= '$snapid' {print}' `echo ${snap_coll_arr[@]}` |tail -n 1
  popd >/dev/null
}

# gather hobject for each snapid
function gen_snapset_hobject()
{
  local func="gen_image_snapset"
  echo "$func ..."
  if [ $# -lt 4 ];then
    echo "$func: parameters: <pool_id> <image_prefix> <snaplist_path> <snapset_output_dir>"
    exit
  fi
  local pool_id=$1
  local image_prefix=$2
  local snaplist_path=$3
  local snapset_output_dir=$4
  pool_id=$(($pool_id))
  OIFS=$IFS
  IFS=$'\n'
  local snaparr=(`cat $snaplist_path`) 
  # gather hobject for each snapshot
  trap 'echo $func failed; exit;' INT HUP
  for line in ${snaparr[@]}
  do
    OOIFS=$IFS
    IFS=$' '
    local field=(`echo $line`)
    local snapid=${field[0]}
    local image_hobjects_stable_snap=$images/pool_$pool_id/$image_prefix/$image_prefix"_"$snapid
    local image_snap=$snapset_output_dir/@$snapid
    gather_hobject_snap $pool_id $image_prefix $snapid 
    local res=$?
    if [ $res -ne 0 ];then
      touch $image_snap
    else 
      mv $image_hobjects_stable_snap $image_snap
    fi
    IFS=$OOIFS
  done
  IFS=$OIFS
}

# lookup image metadata and get snapid hobjects
function discover_image_snap()
{
  local func="discover_image_snap"
  echo "$func ..."
  if [ $# -lt 3 ];then
    echo "$func: paramters: <pool_id> <image_name> [<snap_name>]"
    exit
  fi
  local pool_id=$1
  local image_name=$2
  local snap_name=$3
  pool_id=$(($pool_id))
  #mkdir -p $images/$image_prefix
  lookup_image $pool_id $image_name $snap_name # input image_name and snap_name to lookup metadata and snap_id
  if [ "$db_snap_id"x = ""x ];then
    echo "$func: lookup image failed to gen snapid"
    exit
  fi
  local image_hobjects_dir_prefix=$images/pool_$pool_id/$db_image_prefix
  local image_nosnap=$images/pool_$pool_id/$image_name_in 
  #check if image nosnap recovered
  if [ ! -s $image_nosnap ];then
    echo "$func: please recover image nosnap before recover with snap"
    rm -rf $image_hobjects_dir_prefix
    exit
  fi
  local image_hobject_dir=$images/pool_$pool_id/$image_name_in
  local image_snap_hobject=$image_hobject_dir/$image_name_in@$db_snap_id
  local image_snap_hobject_head=$image_hobject_dir/$image_name_in@$db_snap_id@head
  local image_snaplist=$image_hobject_dir/@snaplist
  local image_snapset_dir=$image_hobject_dir/@snapset_dir
  local image_head=$image_hobject_dir/$image_name_in
  if [ ! -e $image_hobject_dir ];then
    mkdir -p $image_hobject_dir
  fi
  # only gen snapset one time
  if [ ! -e $image_snapset_dir ];then
    mkdir -p $image_snapset_dir
    gen_snapset_hobject $pool_id $db_image_prefix $image_snaplist $image_snapset_dir  
   
  fi

  echo "$func: will get object clone ..."
  >$image_snap_hobject
  >$image_snap_hobject_head

  trap 'echo $func failed; exit;' INT HUP
  # get each offset 's snapid hobject
  while read line
  do
    #echo $line
    OOIFS=$IFS
    IFS=$' '
    local field=(`echo $line`)
    local offset_string=${field[3]}
    IFS=$OOIFS
    local entry=`get_object_clone $offset_string $db_snap_id $image_snaplist $image_snapset_dir` 
    if [ "$entry"x != ""x ];then
      echo $entry >> $image_snap_hobject
      echo `dump_backslash $line` >> $image_snap_hobject_head
    fi
  done < $image_head
  rm -rf $image_hobjects_dir_prefix
}

# after discover_image_nosnap
# collect objects from osds one by one in sequence
function copy_image_nosnap_single_thread()
{
  local func="copy_image_nosnap_single_thread"
  echo "$func ..."
  if [ $# -lt 3 ];then
    echo "$func: parameters: <pool_id> <image_hobjects> <backup_dir>"
    exit
  fi
  local pool_id=$1
  local image_hobjects=$2
  local backup_dir=$3
  pool_id=$(($pool_id))

  # make sure lookup_image first
  if [ $found = 0 ];then
    echo "$func: image not found, maybe forget to discover_image"
    exit
  fi
  if [ ! -e $backup_dir ];then
    mkdir -p $backup_dir
  fi

  local image_dir=$backup_dir/pool_$pool_id/$image_name_in
  local image_file=$image_dir/$image_name_in
  local CURRENT=$image_dir/@CURRENT
  local LOCK=$image_dir/@LOCK
  if [ ! -e $image_dir ];then
    mkdir -p $image_dir
  fi
  if [ -e $LOCK ];then
    echo "$func: $LOCK is locked by other process"
    exit
  else
    touch $LOCK
  fi

  >$image_file
  truncate -s $db_image_size $image_file 
  echo "head">$CURRENT

  local count=$(($db_image_size >> $db_order))
  local start=`cat $image_hobjects|head -n 1|awk '{print $4}'`
  local end=`cat $image_hobjects|tail -n 1|awk '{print $4}'`
  local entry_count=`cat $image_hobjects|wc -l`

  local char_bits=$((`echo $start|wc -c` -1 ))
  local format="%0"$char_bits"x"
  
  local expect_start=`printf $format 0`
  local expect_end=`printf $format $(($count -1 ))`  

  echo -e "object_count\t$entry_count"
  echo -e "expect\t\t[$expect_start ~ $expect_end] count:$count"
  echo -e "range\t\t[$start ~ $end] count:$entry_count"

  local icount=0
  local istart=
  local iend=
  local percent=
  
  trap 'echo $func failed; exit;' INT HUP
  local unit=$((1<<$db_order))
  while read line
  do
  {
    icount=$(($icount+1))
    node=`echo $line|awk '{print $1}'` 
    hobject=`echo $line|awk '{print $3}'` 
    offset=`echo $line|awk '{print $4}'`
    off=$((16#$offset))
    if [ $icount = 1 ];then
      istart=$offset
    fi
    hobject=`dump_backslash $hobject`
    iend=$offset
    sshcmd="cat $hobject"
    ssh $ssh_option $node $sshcmd < /dev/null | dd of=$image_file bs=$unit seek=$off conv=notrunc 2>/dev/null
    percent=`echo "scale=3; 100*$icount/$entry_count"|bc`
    tput sc  #record current cursor
    echo -n -e "complete\t[$istart ~ $iend] $icount/$entry_count ==> "$percent"%"
    if [ $icount != $entry_count ];then
      tput rc # backport most recent cursor
    fi
  }
  done < $image_hobjects

  echo
  echo -n "size: "
  ls -lh $image_file|awk '{print  $5"\t"$9}'
  echo -n "du:   "
  du -h $image_file
  #unlock
  rm -f $LOCK
}


# ssh copy snap_object & head_object from osd to admin node
# copy all snapshot objects 
# and 
# all head objects which have the same offset as snapshot objects 
function collect_image_snap_objects()
{
  local func="collect_image_snap_objects"
  #$1=backup_dir, $2=snap_name, $3=snap_hobjects, $4=head_hobjects
  if [ $# -lt 6 ];then
    echo "$func: parameters: <pool_id> <image_name> <snap_id> <snap_hobjects> <head_hobjects> <backup_dir>"
    exit
  fi  

  local pool_id=$1
  local image_name=$2
  local snap_id=$3
  local snap_hobjects=$4 #snap hobjects info
  local head_hobjects=$5 #head hobjects info
  local backup_dir=$6
  pool_id=$(($pool_id))

  local head_dir=$backup_dir/pool_$pool_id/$image_name/@head
  local snap_dir=$backup_dir/pool_$pool_id/$image_name/@$snap_id
  local CURRENT=$backup_dir/pool_$pool_id/$image_name/@CURRENT
 
  if [ ! -e $head_dir ];then
    mkdir -p $head_dir
  fi
  if [ ! -e $snap_dir ];then
    mkdir -p $snap_dir
  fi

  local snap_node= #osd node
  local snap_hobject= #hobject path with snapid on osd
  local snap_offset=
  local snap_filename=

  local head_node=
  local head_hobject=
  local head_offset=
  local head_filename=

  # ignore if there is no object in snapshot(empty )
  if [ ! -s $snap_hobjects ];then
    echo "$func: $snap_hobjects is empty"
    return 0
  fi
  local start=`head -n 1 $snap_hobjects|awk '{print $4}'`
  local end=`tail -n 1 $snap_hobjects|awk '{print $4}'`
  local entry_count=`cat $snap_hobjects|wc -l`
  if [ $((16#$first_offset)) -gt $((16#$last_offset)) ];then
    echo "$func: $snap_hobjects not sorted"
    return 1
  fi

  # just assert if ignored empty snapshot
  if [ "$start"x = ""x ] || [ "$end"x = ""x ];then
    return 1
  fi
 
  # speed up copy snapshot
  # lookup the coresponding head hobject of snap hobject
  # use command: grep <offset> <head hobjects>
  # 
  # eg.
  # head hobjects: (32 objects, snapid = uint64(-2) = 18446744073709551614)
  # ceph1 29.4d /var/lib/ceph/osd/ceph-0/current/29.4d_head/rb.0.1c414.6b8b4567.000000000000__head_EC2C1C4D__1d 000000000000 18446744073709551614 869
  # ceph1 29.8c /var/lib/ceph/osd/ceph-0/current/29.8c_head/rb.0.1c414.6b8b4567.000000000001__head_0F439A8C__1d 000000000001 18446744073709551614 867
  # ceph1 29.6a /var/lib/ceph/osd/ceph-0/current/29.6a_head/rb.0.1c414.6b8b4567.000000000002__head_FC55706A__1d 000000000002 18446744073709551614 869
  # ceph1 29.8b /var/lib/ceph/osd/ceph-0/current/29.8b_head/rb.0.1c414.6b8b4567.000000000003__head_20A6328B__1d 000000000003 18446744073709551614 869
  # ceph2 29.75 /var/lib/ceph/osd/ceph-1/current/29.75_head/rb.0.1c414.6b8b4567.000000000004__head_AC5ADB75__1d 000000000004 18446744073709551614 867
  # ceph2 29.23 /var/lib/ceph/osd/ceph-1/current/29.23_head/rb.0.1c414.6b8b4567.000000000005__head_1FDEA823__1d 000000000005 18446744073709551614 867
  # ......
  # ceph1 29.34 /var/lib/ceph/osd/ceph-0/current/29.34_head/rb.0.1c414.6b8b4567.00000000001f__head_52373734__1d 00000000001f 18446744073709551614 869
  #
  # snap hobjects: (3 objects, snapid >= 29)
  # ceph1 29.8c /var/lib/ceph/osd/ceph-0/current/29.8c_head/rb.0.1c414.6b8b4567.000000000001__1f_0F439A8C__1d 000000000001 31 867
  # ceph1 29.6a /var/lib/ceph/osd/ceph-0/current/29.6a_head/rb.0.1c414.6b8b4567.000000000002__1e_FC55706A__1d 000000000002 30 869
  # ceph1 29.8b /var/lib/ceph/osd/ceph-0/current/29.8b_head/rb.0.1c414.6b8b4567.000000000003__1d_20A6328B__1d 000000000003 29 869
  #
  # so find out offset in head hobjects line number:
  # snap hobjects: 000000000001 ---> head hobjects: 2 (n1)
  # snap hobjects: 000000000003 ---> head hobjects: 4 (n2)
  # 
  # finally , grep range from the whole file [1 ~ N] shranked to part of file [n1 ~ n2]
  # the worst case : [n1 ~ n2] = [1 ~ N], means no shranking

  # get the line number of the start offset in head hobjects
  local n1=`grep -n $start $head_hobjects|head -n 1|cut -d ":" -f 1`
  # get the line number of the end offset in head hobjects
  local n2=`grep -n $end $head_hobjects|head -n 1|cut -d ":" -f 1`
 
  local icount=0
  local istart=
  local iend=
  local percent=

  OIFS=$IFS
  IFS=$'\n'

  #assume file:snap_hobjects is not very large, and can be loaded into memory
  local snap_arr=(`cat $snap_hobjects`)
  local snap_tmp=/tmp/snaptmp.$$$$

  # snap_tmp: 
  # consists of snap hobject or head hobject
  # select lineno range: [n1 ~ n2]
  head -n $n2 $head_hobjects|tail -n $(($n2-$n1+1)) >$snap_tmp 

  echo "copy image snap/head objects from osd ..."
  echo -e "object_count\t$entry_count"
  echo -e "range\t\t[$start ~ $end] count:$entry_count"

  trap 'echo $func failed; exit;' INT HUP
  for line in ${snap_arr[*]}
  do
    icount=$(($icount+1))    

    OOIFS=$IFS
    IFS=$' '

    local arr=(`echo $line`)
    snap_node=${arr[0]}
    snap_hobject=${arr[2]}
    snap_offset=${arr[3]}
    snap_filename=$snap_dir/$snap_offset

    if [ $icount = 1 ];then
      istart=$snap_offset
    fi
    iend=$snap_offset

    #lookup corresponding head hobject of snap hobject
    local res=`grep $snap_offset $snap_tmp|head -n 1` 
    if [ "$res"x = ""x ];then
      echo "$func: image object[ $snap_offset ] missing"
      exit
    fi
    
    local arr2=(`echo $res`)
    head_node=${arr2[0]}
    head_hobject=${arr2[2]}
    head_offset=${arr2[3]}
    head_filename=$head_dir/$head_offset

    # just copy object(snap/head) if it does not exist
    if [ ! -e $snap_filename ];then
      ssh $ssh_option $snap_node "cat $snap_hobject" > $snap_filename 
    fi
    if [ ! -e $head_filename ];then
      ssh $ssh_option $head_node "cat $head_hobject" > $head_filename 
    fi
    IFS=$OOIFS

    percent=`echo "scale=3; 100*$icount/$entry_count"|bc`
    tput sc  #record current cursor
    echo -n -e "complete\t[$istart ~ $iend] $icount/$entry_count ==> "$percent"%"
    if [ $icount != $entry_count ];then
      tput rc # backport most recent cursor
    fi
  done
  echo
  IFS=$OIFS 
  rm -f $snap_tmp
  return 0
}

# copy all snap objects and corresponding head objects from osds
# in single process
function copy_image_snap_single_thread()
{
  local func="copy_image_snap_single_thread"
  if [ $# -lt 6 ];then
    echo "$func: parameters: <pool_id> <image_name> <snap_id> <snap_hobjects> <head_hobjects> <backup_dir>" 
    exit
  fi
  local pool_id=$1
  local image_name=$2
  local snap_id=$3
  local snap_hobjects=$4
  local head_hobjects=$5
  local backup_dir=$6
  pool_id=$(($pool_id))

  local CURRENT=$backup_dir/pool_$pool_id/$image_name/@CURRENT
  local LOCK=$backup_dir/pool_$pool_id/$image_name/@LOCK
  #lock
  if [ -e $LOCK ];then
    echo "$func: $LOCK is locked by other process"
    exit
  else
    touch $LOCK
  fi
  collect_image_snap_objects $pool_id $image_name $snap_id $snap_hobjects $head_hobjects $backup_dir
  #unlock
  rm -f $LOCK
}

# after all snap objects and necessary head objects are copied,
# just pick appropriate head objects and snap objects and write them to image
# in order to rollback image to snapshot
#
# init: image is created by copy_image_nosnap_single_thread firstly
#
# all output include 3 parts:
# <image>  <head objects>      <snap objects>
# 
#          head objects1  ---  snap1 objects
#          head objects2  ---  snap2 objects
#  image   head objects3  ---  snap3 objects
#          ......
#          head objectsN  ---  snapN objects
#
# how to rollback:
# firstly rollback to head, secondly write <snapX objects>
# head  = <image> + <head objects>
# snap1 = <image> + <head objects> + <snap1 objects>
# snap2 = <image> + <head objects> + <snap2 objects>
# snap3 = <image> + <head objects> + <snap3 objects>
# ......
# snapN = <image> + <head objects> + <snapN objects>
# 
# improve rollback:
# there is intersection of head objects and snapX objects, if snapX objects are not empty
# and need to deduplicate the intersection.
# deduplicate steps:
# - get difference set of head objects and snapX objects
# - write the difference set objects to image
# - write the snapX objects to image
function rollback_image_snap()
{
  local func="rollback_image_snap"
  
  echo "$func ..."
  
  trap 'echo $func failed; exit;' INT HUP
  if [ $# -lt 6 ];then
    echo "$func: parameters <pool_id> <image_name> <snap_id> <snap_object_dir> <backup_dir> <image_unit>"
    exit
  fi
  local pool_id=$1
  local image_name=$2
  local snap_id=$3
  local snap_object_dir=$4
  local backup_dir=$5
  local image_unit=$6

  local need_diff_set=0

  local image_path=$backup_dir/pool_$pool_id/$image_name/$image_name
  local head_object_dir=$backup_dir/pool_$pool_id/$image_name/@head
  local CURRENT=$backup_dir/pool_$pool_id/$image_name/@CURRENT
  local LOCK=$backup_dir/pool_$pool_id/$image_name/@LOCK
  if [ -e $LOCK ];then
    echo "$func: $LOCK is locked by other process"
    exit
  else
    touch $LOCK
  fi
  if [ $snap_id -ne -2 ];then
    echo $snap_id > $CURRENT
  else
    echo "head" > $CURRENT
  fi 

  if [ ! -e $snap_object_dir ];then
    return 0
  fi

  if [ "$snap_object_dir"x != "$head_object_dir"x ];then
    echo "$func: need to compute diff_set of head"
    need_diff_set=1
  else
    echo "$func: NO diff_set"
    need_diff_set=0
  fi

  local entry_count=0
  local start=
  local end=
  local offset=
  local icount=0
  local istart=
  local iend=
  local percent=

  local snap_objects=
  local head_objects=
  local diff_set=

  snap_objects=(`ls $snap_object_dir`)

  # if need to compute difference set of head_objects and snap_objects
  if [ $need_diff_set -ne 0 ];then
    head_objects=(`ls $head_object_dir`) 

    #get the difference set: ( head_objects - snap_objects )
    diff_set=(`
    sort -m <(echo ${head_objects[@]}|xargs -n 1 echo) <(echo ${snap_objects[@]}|xargs -n 1 echo) \
  	<(echo ${snap_objects[@]}|xargs -n 1 echo) |uniq -u`) 

    # copy diff_set of head object to image
    pushd $head_object_dir >/dev/null

    echo "$func: copy diff_set head objects ..."
    entry_count=${#diff_set[@]}  
    start=${diff_set[0]}
    end=
    if [ $entry_count -gt 0 ];then
      end=${diff_set[$(($entry_count - 1))]}
    fi
    offset=
    icount=0
    istart=
    iend=
    percent=

    echo -e "object_count\t$entry_count"
    echo -e "range\t\t[$start ~ $end] count:$entry_count"

    for object in ${diff_set[@]}
    do
      icount=$(($icount+1))
      if [ $icount = 1 ];then
        istart=$object
      fi
      iend=$object

      local offset=$((16#$object))
      dd if=$object of=$image_path bs=$image_unit seek=$offset conv=notrunc 2>/dev/null

      percent=`echo "scale=3; 100*$icount/$entry_count"|bc`
      tput sc  #record current cursor
      echo -n -e "complete\t[$istart ~ $iend] $icount/$entry_count ==> "$percent"%"
      if [ $icount != $entry_count ];then
        tput rc # backport most recent cursor
      fi
    done
    if [ $entry_count -gt 0 ];then
      echo
    fi
    popd >/dev/null

    if [ $snap_id -ne -2 ];then
      echo -e "$image_name already rollback diff_set: (head - snap)"
    fi
  fi
  
  # copy snap object to image
  pushd $snap_object_dir >/dev/null 

  if [ $need_diff_set -ne 0 ];then
    echo "$func: copy snap objects ..."
  else
    echo "$func: copy head objects ..."
  fi
  entry_count=${#snap_objects[@]}  
  start=${snap_objects[0]}
  end=
  if [ $entry_count -gt 0 ];then
    end=${snap_objects[$(($entry_count - 1))]}
  fi
  offset=
  icount=0
  istart=
  iend=
  percent=

  echo -e "object_count\t$entry_count"
  echo -e "range\t\t[$start ~ $end] count:$entry_count"

  for object in ${snap_objects[@]}
  do
    icount=$(($icount+1))
    if [ $icount = 1 ];then
      istart=$object
    fi
    iend=$object

    local offset=$((16#$object))
    dd if=$object of=$image_path bs=$image_unit seek=$offset conv=notrunc 2>/dev/null

    percent=`echo "scale=3; 100*$icount/$entry_count"|bc`
    tput sc  #record current cursor
    echo -n -e "complete\t[$istart ~ $iend] $icount/$entry_count ==> "$percent"%"
    if [ $icount != $entry_count ];then
      tput rc # backport most recent cursor
    fi
  done
  if [ $entry_count -gt 0 ];then
    echo
  fi
  popd >/dev/null

  rm -f $LOCK
  if [ $snap_id -ne -2 ];then
    echo "$image_name rollback to snapid: $snap_id"
  else
    echo "$image_name rollback to head"
  fi
}

function recover_image()
{
  local func="recover_image"
  echo "$func ..."
  
  if [ $# -lt 3 ];then
    echo "$func: paramters: <pool_id> <image_name> <snap_name> [<backup_dir>]"
    exit
  fi

  local pool_id=$1
  local img_name=$2
  local snap_name=$3
  local backup_dir=$4
  pool_id=$(($pool_id))
  if [ "$snap_name"x = "@"x ];then
    snap_name=
  fi
  if [ "$backup_dir"x = ""x ];then
    backup_dir=$default_backup_dir
  fi

  #recover image with nosnap
  if [ "$snap_name"x = ""x ];then
    discover_image_nosnap $pool_id $img_name #input image_name 
    local image_hobjects=$images/pool_$pool_id/$image_name_in/$image_name_in
    copy_image_nosnap_single_thread $pool_id $image_hobjects $backup_dir

  #recover image with snap
  else

    # check if recovered head already
    local img_hobjects_path=$images/pool_$pool_id/$img_name/$img_name
    local img_file_path=$backup_dir/pool_$pool_id/$img_name/$img_name
    if [ ! -e $img_hobjects_path ] || [ ! -e $img_file_path ];then
      echo "$func: $img_name@$snap_name : can not rollback to snapshot, please recover image head first"
      exit
    fi

    # rollback to head
    if [ "$snap_name"x = "@@"x ];then
      local head_dir=$backup_dir/pool_$pool_id/$img_name/@head
      if [ -e $head_dir ];then
	local unit=`pushd $head_dir >/dev/null; ls|head -n 1|xargs -n 1 stat|awk '/Size:/{print $2}'`
        # rollback to head
        rollback_image_snap $pool_id $img_name -2 $backup_dir/$img_name/@head $backup_dir $unit
        echo "$image_name_in head : $backup_dir/$img_name/$img_name"
      else
	echo "$func: no need to rollback to head"
      fi
      return 0
    fi
    
    # rollback to snap
    discover_image_snap $pool_id $img_name $snap_name # get image meta & get snapid object
    local snap_hobjects=$images/pool_$pool_id/$image_name_in/$image_name_in@$db_snap_id
    local head_hobjects=$images/pool_$pool_id/$image_name_in/$image_name_in@$db_snap_id@head
    local snap_object_dir=$backup_dir/pool_$pool_id/$image_name_in/@$db_snap_id
    local image_path=$backup_dir/pool_$pool_id/$image_name_in/$image_name_in
    local image_unit=$((1<<$db_order))
    copy_image_snap_single_thread $pool_id $image_name_in $db_snap_id $snap_hobjects $head_hobjects $backup_dir
    rollback_image_snap $pool_id $image_name_in $db_snap_id $snap_object_dir $backup_dir $image_unit 
    echo "$image_name_in@$snap_name : $image_path"
  fi
}