#!/bin/sh
#BLURB="Create a USB Linux boot stick"
if [ -r /usr/lib/setup/setup ]; then
  RDIR=/dev/tty4
else
  RDIR=/dev/null
fi
TMP=/var/lib/pkgtools/setup/tmp

if [ ! -d $TMP ]; then
  mkdir -p $TMP
fi
if [ -z "$1" ]; then
  T_PX=/
else
  T_PX="$1"
fi
if [ -z "$2" ]; then
  ROOT_DEVICE=$(mount | head -n 1 | cut -f 1 -d ' ')
else
  ROOT_DEVICE="$2"
fi

if [ -r $T_PX/usr/share/syslinux/mbr.bin ]; then
  MBR_BIN=$T_PX/usr/share/syslinux/mbr.bin
elif [ -r /usr/share/syslinux/mbr.bin ]; then
  MBR_BIN=/usr/share/syslinux/mbr.bin
else
  dialog --title "ERROR: USB BOOT STICK NOT CREATED" --msgbox \
  "Master Boot Record file mbr.bin not found. This script requires that the syslinux package is installed." 6 60
  exit
fi

while [ 0 ]; do # the bootdisk menu loop
 # Run "rescan-scsi-bus -l" to get an up to date overview of devices:
 /sbin/rescan-scsi-bus -l 1>$RDIR 2>$RDIR
 # Get a list of removable block devices before the USB stick is inserted:
 echo "" > $TMP/remov_prior
 for BDEV in $(ls --indicator-style none /sys/block | egrep -v "loop|ram"); do
   [ -r /sys/block/$BDEV/removable -a "$(cat /sys/block/$BDEV/removable)" == "1" ] \
     && echo $BDEV >> $TMP/remov_prior
 done
 if [ "$T_PX" = "/" ]; then
   DEFAULTITEM="Create"
 else
   DEFAULTITEM="Skip"
 fi
 dialog --title "MAKE USB FLASH BOOT" --default-item "$DEFAULTITEM" --menu \
"If your computer supports booting from a USB device, it is recommended that you make \
a USB boot stick for your system at this time. It will boot your computer straight \
into the root filesystem on $ROOT_DEVICE. \n\
\n\
Please insert a USB flash memory stick and then press ENTER to create a boot stick. \n\
\n\
WARNING! The existing contents of the USB stick will be erased. \n\
   " 18 70 2 \
 "Create" "Make a USB Linux boot stick" \
 "Skip" "Skip making a USB boot stick" \
 2> $TMP/return
 REPLY=`cat $TMP/return`
 rm -f $TMP/return
 if [ "$REPLY" = "Create" ]; then
  # Run "rescan-scsi-bus -l" to discover our USB stick if needed:
  /sbin/rescan-scsi-bus -l 1>$RDIR 2>$RDIR
  # Get a list of removable block devices after the USB stick is inserted:
  echo "" > $TMP/remov_after
  for BDEV in $(ls --indicator-style none /sys/block | egrep -v "loop|ram"); do
    [ -r /sys/block/$BDEV/removable -a "$(cat /sys/block/$BDEV/removable)" == "1" ] \
      && echo $BDEV >> $TMP/remov_after
  done
  ADDED=$(diff -u $TMP/remov_prior $TMP/remov_after | sed -n 's/^\+//p' | grep -v '^+')
  REMVD=$(diff -u $TMP/remov_prior $TMP/remov_after | sed -n 's/^\+//p' | grep -v '^+')
  if [ -n "$ADDED" ] ; then STICK=$ADDED ; else STICK="" ; fi
  rm $TMP/remov_prior $TMP/remov_after
  if [ ! -n "$STICK" ]; then
   dialog --title "NO NEW DEVICE DETECTED" --ok-label Restart --msgbox  \
"No new USB device was detected. 
If you had already inserted your USB stick, please remove it now. \
Then select 'Restart'." 7 70
   continue
  else
   VENDOR="Vendor : $(cat /sys/block/$STICK/device/vendor)"
   MODEL="Model  : $(cat /sys/block/$STICK/device/model)"
   SIZE="Size   : $(( $(cat /sys/block/$STICK/size) / 2048)) MB"
   dialog --title "NEW DEVICE DETECTED" --yesno \
"A new USB device '/dev/$STICK' was detected with specifications:

--  $VENDOR
--  $MODEL
--  $SIZE

If this is the USB stick to use, select 'Yes',
otherwise select 'No'." 12 70
   if [ $? -eq 1 ]; then
    continue
   fi
  fi

  dialog --title "CREATING USB BOOT STICK" --infobox "Creating SYSLINUX bootdisk for \
$ROOT_DEVICE on /dev/$STICK." 3 64 
  # Create a 16M partition with FAT16. This should be large enough for any kernel (for now).
  PARTSIZE="+16384K"
  # Zero out master boot record and then initialize it with one bootable dos partition  
  dd if=/dev/zero of=/dev/$STICK bs=512 count=1  1> $RDIR 2> $RDIR
  echo "PARTSIZE=$PARTSIZE" 1> $RDIR 
  fdisk /dev/$STICK << EOF 1> $RDIR 2> $RDIR
n
p
1
2048
$PARTSIZE
t 1
6
a
w
EOF
  if [ -x /sbin/mkdosfs ]; then
    /sbin/mkdosfs -I -n USBSLACK -F 16 /dev/${STICK}1 1> $RDIR 2> $RDIR
  else
    chroot $T_PX /sbin/mkdosfs -I -n USBSLACK -F 16 /dev/${STICK}1 1> $RDIR 2> $RDIR
  fi
  sync
  # install syslinux
  if which syslinux-nomtools 1> $RDIR 2> $RDIR ; then
    syslinux-nomtools -i -s /dev/${STICK}1 1> $RDIR 2> $RDIR
  elif which strace 1> $RDIR 2> $RDIR ; then
    # There is a race condition between udev >= 214 and mtools which causes
    # the regular version of syslinux to fail when installing to USB, but
    # strace changes the timing just enough that it usually works:
    strace syslinux -i -s /dev/${STICK}1 1> $RDIR 2> $RDIR
  else
    # This might work when the issues with mtools and udev are addressed,
    # or if syslinux is eventually able to work around them.
    syslinux -i -s /dev/${STICK}1 1> $RDIR 2> $RDIR
  fi
  # make the device bootable:
  echo "dd if=$MBR_BIN of=/dev/$STICK" 1> $RDIR 2> $RDIR
  dd if=$MBR_BIN of=/dev/$STICK  1> $RDIR 2> $RDIR
  sync
  # mount the device and write some configuration files
  if [ ! -d $TMP/bootdisk ]; then
    mkdir $TMP/bootdisk 2> $RDIR
  fi
  mount -t vfat /dev/${STICK}1 $TMP/bootdisk 1> $RDIR 2> $RDIR
  if [ -r $T_PX/boot/vmlinuz ]; then
    cp $T_PX/boot/vmlinuz $TMP/bootdisk/vmlinuz 1> $RDIR 2> $RDIR
  elif [ -r $T_PX/vmlinuz ]; then
    cp $T_PX/vmlinuz $TMP/bootdisk/vmlinuz  1> $RDIR 2> $RDIR
  fi
  cat << EOF > $TMP/bootdisk/message.txt 2> $RDIR

Welcome to the 09Slackware07 Linux custom USB boot stick!

By default, this stick boots a root Linux partition on $ROOT_DEVICE when you
hit ENTER. If you'd like to boot some other partition, use a command like
this on the prompt below:

    mount root=/dev/sda1 ro

Where "/dev/sda1" is the partition you want to boot, and "ro" specifies that
the partition should be initially mounted as read-only. If you wish to mount
the partition read-write, use "rw" instead. To set the video console mode,
use the vga= parameter (press F1 to see a table). You may also add any other
kernel parameters you might need depending on your hardware, and which
drivers are included in your kernel.

EOF
   cat << EOF > $TMP/bootdisk/syslinux.cfg 2> $RDIR
default vmlinuz root=$ROOT_DEVICE vga=normal ro
prompt 1
timeout 6000
display message.txt
F1 f1.txt
F2 message.txt
#F3 f3.txt
#F4 f4.txt
#F5 f5.txt
#F6 f6.txt
#F7 f7.txt
label mount
  kernel vmlinuz
  append root=$ROOT_DEVICE vga=normal ro
EOF
  cat << EOF > $TMP/bootdisk/f1.txt 2> $RDIR
 STANDARD MODES:
 To make the kernel prompt for standard video modes use: vga=ask

 FRAMEBUFFER MODES:
 To get the kernel to start in VESA framebuffer mode, you need to pass it
 a vga= init string on the "boot:" prompt. Here's a table:

   Colors   640x480 800x600 1024x768 1280x1024 1600x1200
  --------+---------------------------------------------
  256     |   769     771      773      775       796
  32,768  |   784     787      790      793       797
  65,536  |   785     788      791      794       798
  16.8M   |   786     789      792      795       799

  ...such as this for 1024x768x64k:
   vga=791

  F2 returns to the previous page.

EOF
  if [ "$(uname -m)" == "x86_64" ]; then # also install an EFI bootloader
    mkdir -p $TMP/bootdisk/EFI/BOOT 1> $RDIR 2> $RDIR
    cp $T_PX/boot/elilo-x86_64.efi $TMP/bootdisk/EFI/BOOT/BOOTX64.EFI 1> $RDIR 2> $RDIR
    cat << EOF > $TMP/bootdisk/EFI/BOOT/message.txt 2> $RDIR

Welcome to the Slackware Linux custom USB boot stick!

By default, this stick boots a root Linux partition on $ROOT_DEVICE when you
hit ENTER. If you'd like to boot some other partition, use a command like
this on the prompt below:

    huge.s root=/dev/sda1 ro

Where "/dev/sda1" is the partition you want to boot, and "ro" specifies that
the partition should be initially mounted as read-only. If you wish to mount
the partition read-write, use "rw" instead. You may also add any other
kernel parameters you might need depending on your hardware, and which
drivers are included in your kernel.

Hit ENTER to boot:

EOF
  cat << EOF > $TMP/bootdisk/EFI/BOOT/elilo.conf 2> $RDIR
chooser=simple
message=message.txt
delay=300
timeout=300
#
image=/vmlinuz
        label=huge.s
        read-only
        append="root=$ROOT_DEVICE vga=normal ro"
EOF
  fi # end EFI installation
  sync
  umount /dev/${STICK}1
  rm -r $TMP/bootdisk
  # Sometimes the nomtools version of syslinux will leave the volume mounted,
  # so umount again:
  umount /dev/${STICK}1 2> $RDIR
  if [ "$T_PX" = "/" ]; then
    dialog --title "USB BOOT STICK CREATED" --msgbox \
    "The USB boot stick has been successfully created on device /dev/$STICK." 6 60
    exit
  fi
  dialog --title "USB BOOT STICK CREATED" --ok-label Continue --cancel-label Create --menu \
"The USB boot stick has been successfully created on device /dev/$STICK. If you would like to \
create an additional boot stick, please select 'Create' and we'll go back and make another \
one, otherwise select 'Continue' to continue configuring your system." 12 71 2 \
 "Continue" "Continue the configuration (done making boot sticks)" \
 "Create" "Make a spare Linux boot stick in /dev/$STICK" \
 2> $TMP/return
  REPLY=`cat $TMP/return`
  rm -f $TMP/return
  if [ "$REPLY" = "Create" ]; then
   continue
  else
   break
  fi
 else # ! Create
  break
 fi
done