#!/bin/sh
#BLURB="Create a USB Linux boot stick"
RDIR=/dev/tty4
NDIR=/dev/null
TMP=/var/log/setup/tmp

if [ ! -d $TMP ]; then
  mkdir -p $TMP
fi
T_PX="$1"
ROOT_DEVICE="$2"

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
 dialog --title "MAKE USB FLASH BOOT" --default-item "Skip" --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 
  # Determine max size of the filesystem (in KB) we want to create:
  USBSIZE=$(( $(cat /sys/block/$STICK/size) / 2048))
  if [ $USBSIZE -lt 512 ]; then DOSSIZE=$(($USBSIZE*1024))
  else DOSSIZE=$((512*1024))
  fi
  # Hack from Pat.  If we're wasting a whole stick, who cares if the partition is
  # extra-small, as long as the kernel fits?  Also, FAT12 is the least problematic.
  DOSSIZE=15861
  if [ -x /sbin/mkdosfs ]; then
    /sbin/mkdosfs -I -n USBSLACK -F 12 /dev/$STICK $DOSSIZE 1> /dev/null 2> /dev/null
  else
    chroot $T_PX /sbin/mkdosfs -I -n USBSLACK -F 12 /dev/$STICK $DOSSIZE 1> /dev/null 2> /dev/null
  fi
  if [ ! -d $TMP/bootdisk ]; then
    mkdir $TMP/bootdisk
  fi
  mount -t vfat /dev/$STICK $TMP/bootdisk 1> /dev/null 2> /dev/null
  if [ -r $T_PX/vmlinuz ]; then
    cp $T_PX/vmlinuz $TMP/bootdisk/vmlinuz
  elif [ -r $T_PX/boot/vmlinuz ]; then
    cp $T_PX/boot/vmlinuz $TMP/bootdisk/vmlinuz
  fi
  # We don't need the isolinux bootloader with syslinux do we?
  #cp $T_PX/usr/share/syslinux/isolinux.bin $TMP/bootdisk/
  cat << EOF > $TMP/bootdisk/message.txt

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 > $TMP/bootdisk/syslinux.cfg
default vmlinuz root=$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
 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
  umount /dev/$STICK
  rm -r $TMP/bootdisk
  # Make the device bootable:
  syslinux -s /dev/$STICK 1> /dev/null 2> /dev/null
  dialog --title "USB BOOT STICK CREATED" --ok-label Continue --cancel-label Create --menu \
"The USB boot stick has been successfully created in /dev/$STICK.  If you would like to \
create an additional boot stick, please select 'Create' and we'll go back and make another \
one, otherwise select 'Continue' to continue configuring your system." 12 70 2 \
 "Continue" "Continue the configuration (done making boot sticks)" \
 "Create" "Make a spare Linux boot stick in /dev/$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