#!/bin/bash
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#boot.img tool
#by xiaolu
trap "clean" 2 3 4
workdir=$(pwd)
toolpath=$(readlink -f $0)
tooldir=$(dirname $toolpath)
mkbootimg=$tooldir/mkbootimg
old_bootimg=true
C_OUT="\033[0;1m"
C_ERR="\033[31;1m"
C_CLEAR="\033[0;0m"

pout() {
    printf "${C_OUT}${*}${C_CLEAR}\n"
}
perr() {
    printf "${C_ERR}${*}${C_CLEAR}\n"
}
clean()
{
    rm -rf /tmp/mkboot.*
    pout "..."
    exit
}

usage()
{
    pout "<Unpack and repack boot.img tool>"
    pout "----------------------------------------------------------------------"
    pout "Not enough parameters or parameter error!"
    pout "unpack boot.img & decompress ramdisk：\n    $(basename $0) [img] [output dir]"
    pout "    $(basename $0) boot.img boot20130905"
    pout "Use the unpacked directory repack boot.img(img_info)：\n    $(basename $0) [unpacked dir] [newbootfile]"
    pout "    $(basename $0) boot20130905 newboot.img"
    clean
}

print_info()
{
    pout "  kernel         : $kernel"
    pout "  ramdisk        : $ramdisk"
    pout "  page size      : $page_size"
    pout "  kernel size    : $kernel_size"
    pout "  ramdisk size   : $ramdisk_size"
    [ ! -z $second_size ] && [ $second_size -gt 0 ] && \
        pout "  second_size    : $second_size"
    [ $dtb_size -gt 0 ] && pout "  dtb size       : $dtb_size"
    pout "  base           : $base_addr"
    pout "  kernel offset  : $kernel_offset"
    pout "  ramdisk offset : $ramdisk_offset"
    [ -z $second_offset ] || pout "  second_offset  : $second_offset"
    pout "  tags offset    : $tags_offset"
    [ $dtb_size -gt 0 ] && pout "  dtb img        : $dt"
    pout "  cmd line       : $cmd_line"
}

mkboot_img()
{
    error=0
    if [ $dtb_size -gt 0 ]; then
        dtb="--dt ${dt}"
    fi
    $mkbootimg --kernel $kernel --ramdisk $ramdisk \
        --base $base_addr --ramdisk_offset $ramdisk_offset \
        --tags_offset $tags_offset --cmdline "$cmd_line" \
        --pagesize $page_size $dtb -o $1 || error=1
    [ $error -eq 1 ] && return $error
    ramdisk_size=$(stat -c "%s" $ramdisk)
    boot_size=$(stat -c "%s" $1)
    pout "Kernel size: $kernel_size, new ramdisk size: $ramdisk_size, $(basename $1): $boot_size."
    pout "$(basename $1) has been created."
}

#decide action
[ $# -lt 2 ] || [ $# -gt 3 ] && usage
if [ $# -eq 2 ] && [ -d $1 ]; then
    mkboot_from_dir=1
elif [ $# -eq 2 ] && [ -s $1 ]; then
    split_boot_to_dir=1
else
    usage
fi

#mkboot_from_dir, img_info
if [ ! -z $mkboot_from_dir ]; then
    pout "mkbootimg from $1/img_info."
    unpacked_dir=$(readlink -f $1)
    new_img=$(readlink -f $2)
    cd $unpacked_dir
    if [ ! -s img_info ]; then
        pout "not found img_info file! can't rebuild img."
        clean
    fi 
    eval $(cat img_info)
    if [ -z $kernel ] || [ -z $ramdisk ] || [ -z $base_addr ]; then
        pout "img_info file have not enough parameters."
        clean
    fi
    [ -z $dtb_size ] && dtb_size=0
    if [ -d $ramdisk ]; then
        #cd $ramdisk
        #find . | cpio -R 0:0 -H newc -o 2>/dev/null | gzip > $unpacked_dir/new_ramdisk.gz
        mkbootfs $ramdisk | gzip > new_ramdisk.gz
        ramdisk=new_ramdisk.gz
        ramdisk_size=$(stat -c "%s" $ramdisk)
    fi
    #cd $unpacked_dir
    print_info
    rm -f $new_img
    mkboot_img $new_img || perr "Make boot.img Error! pls check img_info file."
    #pout "Add SEANDROIDENFORCE tag."
    #printf SEANDROIDENFORCE >> $new_img
    rm -f new_ramdisk.gz
    clean
fi

#split boot.img to dir.
if [ -e $2 ]; then
    read -p "$2 exists, delete?(N/y)" reply
    case $reply in
        y | Y)
        rm -rf $2
        ;;
    *)
        exit
        ;;
    esac
fi
tempdir="$(readlink -f $2)"
mkdir -p $tempdir
pout "Unpack & decompress $1 to $2"

#get boot.img info
cp -f $1 $tempdir/
cd $tempdir
bootimg=$(basename $1)
offset=$(grep -abo ANDROID! $bootimg | cut -f 1 -d :)
[ -z $offset ] && clean
if [ $offset -gt 0 ]; then
    dd if=$bootimg of=bootimg bs=$offset skip=1 2>/dev/null
    bootimg=bootimg
fi

kernel_addr=0x$(od -A n -X -j 12 -N 4 $bootimg | sed 's/ //g' | sed 's/^0*//g')
ramdisk_addr=0x$(od -A n -X -j 20 -N 4 $bootimg | sed 's/ //g' | sed 's/^0*//g')
second_addr=0x$(od -A n -X -j 28 -N 4 $bootimg | sed 's/ //g' | sed 's/^0*//g')
tags_addr=0x$(od -A n -X -j 32 -N 4 $bootimg | sed 's/ //g' | sed 's/^0*//g')

kernel_size=$(od -A n -D -j 8 -N 4 $bootimg | sed 's/ //g')
base_addr=0x$(od -A n -x -j 14 -N 2 $bootimg | sed 's/ //g')0000
ramdisk_size=$(od -A n -D -j 16 -N 4 $bootimg | sed 's/ //g')
second_size=$(od -A n -D -j 24 -N 4 $bootimg | sed 's/ //g')
page_size=$(od -A n -D -j 36 -N 4 $bootimg | sed 's/ //g')
dtb_size=$(od -A n -D -j 40 -N 4 $bootimg | sed 's/ //g')
cmd_line=$(od -A n --strings -j 64 -N 512 $bootimg)

kernel_offset=$((kernel_addr-base_addr))
ramdisk_offset=$((ramdisk_addr-base_addr))
second_offset=$((second_addr-base_addr))
tags_offset=$((tags_addr-base_addr))

base_addr=$(printf "0x%08x" $base_addr)
kernel_offset=$(printf "0x%08x" $kernel_offset)
ramdisk_offset=$(printf "0x%08x" $ramdisk_offset)
second_offset=$(printf "0x%08x" $second_offset)
tags_offset=$(printf "0x%08x" $tags_offset)

k_count=$(((kernel_size+page_size-1)/page_size))
r_count=$(((ramdisk_size+page_size-1)/page_size))
s_count=$(((second_size+page_size-1)/page_size))
d_count=$(((dtb_size+page_size-1)/page_size))
k_offset=1
r_offset=$((k_offset+k_count))
s_offset=$((r_offset+r_count))
d_offset=$((s_offset+s_count))

#zImage
dd if=$bootimg of=zImage_tmp bs=$page_size skip=$k_offset count=$k_count 2>/dev/null
dd if=zImage_tmp of=zImage bs=$kernel_size count=1 2>/dev/null
#ramdisk.gz
dd if=$bootimg of=ramdisk_tmp bs=$page_size skip=$r_offset count=$r_count 2>/dev/null
dd if=ramdisk_tmp of=ramdisk.gz bs=$ramdisk_size count=1 2>/dev/null
#dtb
if [ $dtb_size -gt 0 ]; then
    dd if=$bootimg of=dt.img_tmp bs=$page_size skip=$d_offset count=$d_count 2>/dev/null
    dd if=dt.img_tmp of=dt.img bs=$dtb_size count=1 2>/dev/null
    dt="$tempdir/dt.img"
    dt=$(basename $dt)
    dt_name="dt=$dt\n"
    dt_size="dtb_size=$dtb_size\n"
fi
rm -f *_tmp $(basename $1) $bootimg

kernel=zImage
ramdisk=ramdisk
[ ! -s $kernel ] && clean
#print boot.img info
print_info

#write info to img_info,decompression ramdisk.gz
printf "kernel=zImage\nramdisk=ramdisk\n${dt_name}page_size=$page_size\n\
kernel_size=$kernel_size\nramdisk_size=$ramdisk_size\n${dt_size}base_addr=$base_addr\nkernel_offset=$kernel_offset\n\
ramdisk_offset=$ramdisk_offset\ntags_offset=$tags_offset\ncmd_line=\"$cmd_line\"\n" > img_info
mkdir ramdisk
cd ramdisk

gzip -t ../ramdisk.gz
if [ $? -gt 0 ]; then

    lzma -t ../ramdisk.gz
    if [ $? -gt 0 ]; then
        #try lz4
        $tooldir/lz4 -d ../ramdisk.gz ../ramdisk.cpio
        if [ $? -gt 0 ]; then
            pout "ramdisk is unknown format,can't unpack ramdisk"
    	    rm ../ramdisk.cpio
        else
            pout "ramdisk is lz4 format."
            cpio -i -d -m  --no-absolute-filenames 2>/dev/null < ../ramdisk.cpio
        fi
    else
        pout "ramdisk is lzma format."
        lzma -d -c ../ramdisk.gz | cpio -i -d -m  --no-absolute-filenames 2>/dev/null
    fi
else
    pout "ramdisk is gzip format."
    gzip -d -c ../ramdisk.gz | cpio -i -d -m  --no-absolute-filenames 2>/dev/null
fi
#Unpack Finish to exit.
pout "Unpack completed."
exit