#!/bin/bash
# Author: Guo Wenxue<guowenxue@gmail.com>  QQ: 281143292
#
# This script will create a bootable SD card and install u-boot into it. 
# Formatting can be skipped if the SD card is already formatted properly.
# SD card had better smaller than 16GB.
#
# It must be run with root permissions. Example:
#   $ sudo ./uboot-sdcard.sh
#

PWD=`pwd`
PRJ_PATH=`dirname ${PWD}`
IMG_PATH=${PRJ_PATH}/linux-bsp/images

function check_root_run()
{ 
   AMIROOT=`whoami | awk {'print $1'}` 
   if [ "$AMIROOT" != "root" ] ; then 
      echo "" 
      echo "  **** Error *** must run script with sudo"
      echo ""
      exit
   fi
}

# find the avaible SD cards
function find_avaible_sdcard()
{ 
   echo " "
   echo "Availible Drives to write images to: "
   echo " "
   
   ROOTDRIVE=`mount | grep 'on / ' | awk {'print $1'} |  cut -c6-8`
   echo "#  major   minor    size   name "
   cat /proc/partitions | grep -v $ROOTDRIVE | grep '\<sd.\>' | grep -n ''
   echo " "

   ENTERCORRECTLY=0
   while [ $ENTERCORRECTLY -ne 1 ]
   do
      read -p 'Enter Device Number: ' DRIVENUMBER
      echo " "

      DEVNAME=`cat /proc/partitions | grep -v 'sda' | grep '\<sd.\>' | grep -n '' | grep "${DRIVENUMBER}:" | awk '{print $5}'`
      DRIVE=/dev/$DEVNAME
      DEVSIZE=`cat /proc/partitions | grep -v 'sda' | grep '\<sd.\>' | grep -n '' | grep "${DRIVENUMBER}:" | awk '{print $4}'`

      if [ -n "$DEVNAME" ] ; then
	 ENTERCORRECTLY=1
	 echo "$DEVNAME was selected"
      else
	 echo "Invalid selection"
      fi

      echo ""
    done

}

function check_umount_sdcard()
{
echo ""
echo "+-----------------------------------------+"
echo "|    Check and umount SD card $DEVNAME    |"
echo "+-----------------------------------------+"
echo ""

   #unmount drives if they are mounted
   unmounted1=`df | grep '\<'$DEVNAME'1\>' | awk '{print $1}'`
   unmounted2=`df | grep '\<'$DEVNAME'2\>' | awk '{print $1}'`
   unmounted3=`df | grep '\<'$DEVNAME'3\>' | awk '{print $1}'`

   if [ -n "$unmounted1" ] ; then 
      echo " unmounted ${DRIVE}1" 
      sudo umount -f ${DRIVE}1 
   fi

   if [ -n "$unmounted2" ] ; then 
      echo " unmounted ${DRIVE}2" 
      sudo umount -f ${DRIVE}2 
   fi

   if [ -n "$unmounted3" ] ; then 
      echo " unmounted ${DRIVE}3" 
      sudo umount -f ${DRIVE}3 
   fi
}

function check_partition_sdcard()
{
echo ""
echo "+-----------------------------------------+"
echo "|      Check SD cards partitions          |"
echo "+-----------------------------------------+"
echo ""

   # check to see if the device is already partitioned
   SIZE1=`cat /proc/partitions | grep -v 'sda' | grep '\<'$DEVNAME'1\>'  | awk '{print $3}'`
   SIZE2=`cat /proc/partitions | grep -v 'sda' | grep '\<'$DEVNAME'2\>'  | awk '{print $3}'`
   SIZE3=`cat /proc/partitions | grep -v 'sda' | grep '\<'$DEVNAME'3\>'  | awk '{print $3}'`
   SIZE4=`cat /proc/partitions | grep -v 'sda' | grep '\<'$DEVNAME'4\>'  | awk '{print $3}'`

   echo " ${DEVNAME}1   ${DEVNAME}2     ${DEVNAME}3"
   echo $SIZE1 $SIZE2 $SIZE3
   echo ""

   PARTITION="0"
   if [ -n "$SIZE1" -a -n "$SIZE2" ] ; then
      if  [ "$SIZE1" -gt "72000" -a "$SIZE2" -gt "700000" ] ; then 
          echo  "Detected device has partitions already"
	  PARTITION=1
      fi
   else
      echo "WARN: SD Card is not correctly partitioned"
   fi

}

function format_sdcard()
{ 
   check_partition_sdcard

   if [ $PARTITION -eq 1 ] ; then
      ENTERCORRECTLY=0
      while [ $ENTERCORRECTLY -ne 1 ]
      do
         echo ""
         read -p 'Would you like to re-partition the drive anyways [y/n] : ' CASEPARTITION
         ENTERCORRECTLY=1

         echo ""
         case $CASEPARTITION in
	     "y")  echo "Now partitioning $DEVICEDRIVENAME ...";PARTITION=0;;
	     "n")  echo "Skipping partitioning"; return ;;
	       *)  echo "Please enter y or n";ENTERCORRECTLY=0;;
         esac
       done
   fi


echo ""
echo "+-----------------------------------------+"
echo "|        Now making 2 partitions          |"
echo "+-----------------------------------------+"
echo ""

   dd if=/dev/zero of=$DRIVE bs=1024 count=1024
   SIZE=`fdisk -l $DRIVE | grep Disk | awk '{print $5}'`
   echo DISK SIZE - $SIZE bytes

   # 每一个柱面的大小为255*63*512=8,225,280 Bytes
   CYLINDERS=`echo $SIZE/255/63/512 | bc`

# sfdisk的-D参数指定与DOS兼容，并自动在每个分区前预留空间，以存放MBR（Master Boot Record);
# 第一行分区描述,40,0x0C,*, 自动分配起始柱面，数量为40，分区ID为0x0C(表示FAT32分区），< bootable >为*, 表示可启动分区。
# 第二行分区描述,41,,,-, 起始柱面为41，后面的所有空间分配到该分区。

sfdisk -D -H 255 -S 63 -C $CYLINDERS $DRIVE << EOF
,40,0x0C,*
41,,,-
EOF


echo ""
echo "+-----------------------------------------+"
echo "|     Format boot partition as FAT        |"
echo "+-----------------------------------------+"
echo ""
    mkfs.vfat -F 32 -n "boot" ${DRIVE}1


echo ""
echo "+-----------------------------------------+"
echo "|     Format rootfs partition as ext3     |"
echo "+-----------------------------------------+"
echo ""
    mkfs.ext3 -L "rootfs" ${DRIVE}2


    sync 
    sync
}

function install_uboot()
{

echo ""
echo "+-----------------------------------------+"
echo "|     Install bootloader into SD card     |"
echo "+-----------------------------------------+"
echo ""

   ENTERCORRECTLY=0
   while [ $ENTERCORRECTLY -ne 1 ]
   do
      read -p 'Would you like to continue install u-boot ? [y/n] : ' EXITQ 
      echo ""
      echo " "
     
      ENTERCORRECTLY=1
      case $EXITQ in
           "n") ;;
	   "y") 
	       mkdir /media/{boot,rootfs} 2> /dev/null
	       sudo mount ${DRIVE}1 /media/boot 

	       COPY=0

	       if [ -s ${IMG_PATH}/MLO ] ; then
		  echo "cp -f ${IMG_PATH}/MLO /media/boot"
                  cp -f ${IMG_PATH}/MLO /media/boot
		  COPY=1
	       fi

	       if [ -s ${IMG_PATH}/u-boot.img ] ; then
		  echo "cp -f ${IMG_PATH}/u-boot.img /media/boot"
                  cp -f ${IMG_PATH}/u-boot.img /media/boot
		  COPY=2
	       fi

	       if [ $COPY != 2 ] ; then
		  echo "ERROR: MLO or u-boot.img copy failure"
	       fi

	       echo "ls /medial/boot"
	       ls --color /media/boot

	       echo ""
	       echo "Install bootloader done"
	       echo ""

	       sudo umount /media/boot
	       return;;
	     
	   *)  echo "Please enter y or n"; ENTERCORRECTLY=0;;
      esac 
   done 
}


check_root_run

find_avaible_sdcard

check_umount_sdcard

format_sdcard

install_uboot