#!/bin/bash
# file: metadata_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/epoch_h

# put origin name in $image_name_in: for output
# put convert "_" name in $image_name: for grep image hobjects from database
image_name_in=
image_name=
function input_image()
{
  local func="input_image"
  if [ "$1"x = ""x ];then
    echo "$func: no image name input"
    exit
  fi

  image_name_in=$1
  # "_" -> "\u"
  image_name=`convert_underline $image_name_in`
}

#======================================== distinguish v1 or v2 ===================================  
#image_list_v1=$single_node/$cluster-$id/image_list_v1
#image_list_v2=$single_node/$cluster-$id/image_list_v2
function get_image_list()
{
  find $osd_data/current/ -type f|grep ".rbd__" >$image_list_v1
  find $osd_data/current/ -type f|grep "rbd\\\\uid." >$image_list_v2
}

function get_image_format_by_hobject()
{
  local func="get_image_format"
  if [ "$1"x = ""x ];then
    exit
  fi
  local res1=`cat $image_list_v1|grep $1`  
  if [ "$res1"x != ""x ];then
    echo 1
    exit
  fi  
 
  local res2=`cat $image_list_v2|grep  $1`
  if [ "$res2"x = ""x ];then
    echo 2
    exit
  fi
}

#======================================== image format v1 ========================================  
# <image_name>.rbd inlude 3 parts:
# header + snap_count*snapshot + snap_count*snap_name
# 
# struct rbd_obj_header_ondisk {
# 40	char text[40];
# 24	char block_name[RBD_MAX_BLOCK_NAME_SIZE];
# 4	char signature[4];
# 8	char version[8];
# 	struct {
# 1		__u8 order;
# 1		__u8 crypt_type;
# 1		__u8 comp_type;
# 1		__u8 unused;
# 	} __attribute__((packed)) options;
# 8	__le64 image_size;//hexdump -C s=80 n=8
# 8	__le64 snap_seq;  //hexdump -C s=88 n=8
# 4	__le32 snap_count;//hexdump -C s=96 n=4
# 4	__le32 reserved;
# 8	__le64 snap_names_len;//hexdump -C s=104 n=8
# 	struct rbd_obj_snap_ondisk snaps[0];
# } __attribute__((packed));
#
# sizeof(rbd_obj_header_ondisk): 112
#
# struct rbd_obj_snap_ondisk {
# 8	__le64 id;    //hexdump -C s=112+i*16 n=8   , i=[0, snap_count)
# 8	__le64 image_size;//hexdump -C s=112+i*16+8 n=8, i=[0, snap_count)
# } __attribute__((packed));
# sizeof(rbd_obj_snap_ondisk): 16
#
# get snap_names form <image_nane>.rbd
# hexdump -e '10/1 "%_c"' -s $((112 + $snap_count*16)) -n $snap_names_len <image_name>.rbd
# then split snap_names into array

function get_image_metadata_v1()
{
  local func="get_image_metadata_v1"
  if [ "$1"x = ""x ];then
    echo "$func: no image head object input"
    exit
  fi
  local snap_name=
  if [ "$2"x != ""x ];then
    snap_name=$2 
  fi
    
  if [ ! -e $1 ];then
    echo "$func: $1 not exists"
    exit
  fi
  local hobject_path=$1  
  d_hobject_path=`dump_backslash $1`
  local image_format=`get_image_format_by_hobject $d_hobject_path`
  if [ $image_format != 1 ];then
    echo "$func: image_format must be 1"
    exit
  fi
 
  if [ ! -e $hobject_path ];then
    echo "$func: $hobject_path not exists"
    exit
  fi

  # decode rbd_obj_header_ondisk of <image_name>.rbd
  local block_name=`hexdump -e '10/1 "%c"' -s 40 -n 24 $hobject_path`
  local order=`hexdump -e '10/4 "%u"' -s 76 -n 1 $hobject_path`
  local image_size=`hexdump -C -s 80 -n 8 $hobject_path|head -n 1|awk '{for (i=9; i>1; i--) {printf $i}}'`
  image_size=$((16#$image_size))
  local snap_seq=`hexdump -C -s 88 -n 8 $hobject_path|head -n 1|
	awk '{num=""; for(i=9; i>1; i--){ num=num""$i;} print strtonum("0x"num);}'`
  local snap_count=`hexdump -C -s 96 -n 4 $hobject_path|head -n 1|
	awk '{num=""; for(i=5; i>1; i--){ num=num""$i;} print strtonum("0x"num);}'` 
  local snap_names_len=`hexdump -C -s 104 -n 8 $hobject_path|head -n 1|
	awk '{num=""; for(i=9; i>1; i--){ num=num""$i;} print strtonum("0x"num);}'` 

  echo -e "block_name:\t$block_name"
  echo -e "order:\t\t$order"
  echo -e "image_size:\t$image_size"
  echo -e "snap_seq:\t$snap_seq"

  # decode N rbd_obj_snap_ondisk of <image_name>.rbd
  declare -a snap_ids
  declare -a snap_names
  declare -a snap_image_sizes
  local size_header=112 #sizeof(rbd_obj_header_ondisk)
  local size_snap=16 #sizeof(rbd_obj_snap_ondisk)
  local offset=0
  local id_off=0
  local size_off=0
  for ((i=0; i<$snap_count; i++))
  do
    offset=$(($size_header + $i * $size_snap)) 
    id_off=$offset 
    size_off=$(($offset + 8))
    snap_ids[$i]=`hexdump -C -s $id_off -n 8 $hobject_path|head -n 1|
	awk '{num=""; for(i=9; i>1; i--){num=num""$i;} print strtonum("0x"num);}'`
    snap_image_sizes[$i]=`hexdump -C -s $size_off -n 8 $hobject_path|head -n 1|
	awk '{num=""; for(i=9; i>1; i--){num=num""$i;} print strtonum("0x"num);}'`
  done
  offset=$(($size_header + $snap_count * $size_snap))
  snap_names=(`hexdump -e '10/1 "%_c"' -s $offset -n $snap_names_len $hobject_path|
  	awk -F "\\\\\\\\\\\\\\\\0" '{for(i=1; i<=NF; i++) {print $i" "} }'`); 

  echo -e "\t\tID\tNAME\t\tSIZE"
  for ((i=0; i<$snap_count; i++))
  do
    if [ "$snap_name"x = ""x ];then
      echo -n -e "snapshot:\t"
      echo -e "${snap_ids[$i]}\t${snap_names[$i]}\t\t${snap_image_sizes[$i]}"
      continue
    fi
    if [ "$snap_name"x = "${snap_names[$i]}"x ];then 
      echo -n -e "snapshot:\t"
      echo -e "${snap_ids[$i]}\t${snap_names[$i]}\t\t${snap_image_sizes[$i]}"
      return
    fi
  done
}

#======================================== end image format v1 ========================================  

#======================================== image format v2 ======================================== 

# map_header, header_seq, header, key/value
# eg. 
# map_header		_HOBJTOSEQ_:rbd%uheader%e139a6b8b4567...head.2.68E826B6
# meta_header_seq	17426
# header:		_USER_0000000000017426_USER_:object_prefix
#			_USER_0000000000017426_USER_:order
#			_USER_0000000000017426_USER_:size
#			_USER_0000000000017426_USER_:snap_seq
# key/value		ceph-kvstore-tool /storepath get _USER_0000000000017426_USER_ (object_prefix|order|size|snap_seq)

# decode image id from image_id_hobject 
function get_image_id()
{
  local func="get_image_id"
  if [ "$1"x = ""x ];then
    exit;
  fi
  local image_id_hobject=$1 #from admin node's database

  if [ ! -e $image_id_hobject ];then
    #echo "$func: $image_id_hobject not exists"
    exit;
  fi
  
  # get len of string  
  local n=`hexdump -e '10/4 "%u"' -s 0 -n 4 $image_id_hobject`
  # get string
  hexdump -e '10/1 "%c"' -s 4 -n $n $image_id_hobject
}

#find image_id omap entry in omaplist
map_header_prefix=
map_header_key=
function get_map_header()
{
  local func="get_map_header"
  local image_id=$1
  if [ "$image_id"x = ""x ];then
    echo "$func: no image_id input"
    exit;
  fi
  map_header_prefix=`get_map_header_prefix`
  local keyword="header%e"$image_id
  map_header_key=`get_map_header_key $keyword`
  if [ "$map_header_key"x = ""x ];then
    echo "$func: map_header_key is NULL(not in omaplist)"
    exit
  fi
}

#get meta header seq from map_header
meta_header_seq=
function get_meta_header_seq() 
{
  local func="get_meta_header_seq"
  if [ "$1"x == ""x ];then
    echo "$func: no prefix input"
    exit;
  elif [ "$2"x == ""x ];then
    echo "$func: no key input"
    exit;
  fi
  local prefix=$1;
  local key=$2;
  meta_header_seq=`get_header_seq $prefix $key`
}

# get image metadata : object_prefix, order, image_size, snap_seq
object_prefix=
order=
image_size=
snap_seq=
function get_image_metadata_v2()
{
  local func="get_image_metadata_v2"
  if [ "$1"x = ""x ];then
    echo "$func: no meta_header_seq input"
    exit;
  fi
  local meta_header_seq=`printf "%016d" $1`
  #echo "$func: meta_header_seq = "$meta_header_seq
  local ghobject_key="_USER_"$meta_header_seq"_USER_"
  local prefix=$ghobject_key

  object_prefix=`get_header_kv $prefix object_prefix string`
  #object_prefix="rbd_data.$image_id"
  order=`get_header_kv $prefix order int`
  image_size=`get_header_kv $prefix size int` 
  snap_seq=`get_header_kv $prefix snap_seq int`

  echo -e "object_prefix:\t$object_prefix"
  echo -e "order:\t\t$order"
  echo -e "image_size:\t$image_size"
  echo -e "snap_seq:\t$snap_seq"

  # list snapshot
  list_snaps_v2 $1 $2
}

# struct cls_rbd_snap {
# 	snapid_t id;
#	string name;
#	uint64_t image_size;
#	uint64_t features;
#	uint8_t protection_status;
#	cls_rbd_parent parent;
# }
# decode cls_rbd_snap
# 1	u8	struct_v
# 1	u8	struct_compat
# 4	u32	struct_len
# 8	u64	snapid_t id //s=6 n=8
# 4	u32	len of name //s=14 n=4
# len	char	name        //s=18 n=len
# 8	u64	image_size
# 8	u64	features
# ......
#
function list_snaps_v2()
{
  local func="list_snaps_v2"
  if [ "$1"x = ""x ];then
    exit
  fi
  local sname=
  if [ $# -eq 2 ];then
    sname=$2
  fi
  local meta_header_seq=`printf "%016d" $1`
  local prefix="_USER_"$meta_header_seq"_USER_"
  local keys=(`awk -F ":" '/snapshot_/ && $1 == "'"$prefix"'" {if ($2 == "") exit; split($2, arr, "_"); 
	print arr[2];}' $omap_list|sort -r`)
  echo -e "\t\tID\tNAME\t\tSIZE"
  for key in ${keys[@]}
  do
    key="snapshot_$key"
    local arr=(`ceph-kvstore-tool $omap_path get $prefix $key|awk -F ":" '{print $2}'`);
    # get snap_name
    tmp=
    for ((i=17; i>13; i--))
    do
      tmp="$tmp${arr[$i]}"
    done
    local len=$((16#$tmp))
    local snap_name=
    for ((i=18; i<$((18+$len)); i++))
    do
      # convert ascii to char
      local char=`echo -e "\x${arr[$i]}"` 
      snap_name="$snap_name$char"
    done
    # get snap_id (little endian)
    local tmp=
    for ((i=13; i>5; i--))
    do
      tmp="$tmp${arr[$i]}" 
    done
    local snap_id=$((16#$tmp))
    # get image_size of current snap (little endian)
    tmp=
    for ((i=$((25+$len)); i>$((17+$len)); i--))
    do
      tmp="$tmp${arr[$i]}"
    done
    local image_size=$((16#$tmp))
    if [ "$sname"x = ""x ];then
      echo -e "snapshot:\t$snap_id\t$snap_name\t\t$image_size" 
      continue
    fi
    if [ "$sname"x = "$snap_name"x ];then
      echo -e "snapshot:\t$snap_id\t$snap_name\t\t$image_size" 
      return
    fi
  done
}

#======================================== end image format v2 ========================================