#!/bin/sh
 
# Copyright (c) 2003-2004 Gideon Romm (Symbio Technologies, LLC)
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
# SYMBIO TECHNOLOGIES BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
# OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
#
# This hotplug program expands on ideas of my previous work and work 
# done by Scott Balneaves.
#
# Version: 0.5
#
# Changelog:
#
# 0.5:
#
#   - Added support for USB flash sticks that report bad partition tables 
#     yet *should* be mounted as ../disc 
# 
# 0.4:
#   - Fixed bug in symbolic link generation
# 
# 0.3:
#   - Reverted to scotty's mount/unmount scripts 
#
# 0.2:
#   - Modified parser 
# 0.1: 
#   - Initial release

# Hotplug will run this script and set the following environment variables:
#
# ACTION - What action to take: eg. add/remove
# DEVPATH - On 2.6 kernels, the sysfs directory for the device
# PRODUCT -  idVendor/idProduct/bcdDevice, from device descriptor. Numbers are
#            hexadecimal, without leading '0x' or zeros: eg.  46d/c281/108
# TYPE -  bDeviceClass/bDeviceSubClass/bDeviceProtocol, from device descriptor
#         when 0/*/* is seen, a variable of type INTERFACE is also provided. 
#         Numbers are decimal:  eg. 9/0/0
# INTERFACE -  bInterfaceClass/bInterfaceSubClass/bInterfaceProtocol
#              only for device class zero.
#              Linux 2.6 gives each interface its own hotplug event, and
#              /sys/$DEVPATH/bInterfaceNumber tells them apart. Earlier 
#              kernels only reported the first interface. Numbers are decimal.
#              eg. 3/1/1
# DEVFS - Where USB drivers list lives: eg. /proc/bus/usb
# DEVICE - The path to the usbdevfs node for this device: 
#          eg. /proc/bus/usb/002/008

#######################
#      The Plan       #
#######################
#
# When an "add" ACTION is triggered, we will search a lookup table for 
# an appropriate module to load.
# Call the function add_<module_name>
# If the module is not found, let's assume usb-storage...
#
# When a "remove" ACTION is triggered, then we will run remove_<module_name>
# and attempt to remove the module

#######################
#  Set up environment #
#######################

# For unknown devices, this will allow us to check syslog for IDs
logger "PRODUCT: $PRODUCT (idVendor/idProduct/bcdDevice)"
logger "TYPE: $TYPE (bDeviceClass/bDeviceSubClass/bDeviceProtocol)"
logger "INTERFACE: $INTERFACE (bInterfaceClass/bInterfaceSubClass/bInterfaceProtocol)"

#
# Directories
#
DRIVESDIR=/tmp/drives
HOTPLUGDIR=/tmp/drives/.hotplug
PROCSCSI=/proc/scsi/scsi
SUPERMOUNTS=/proc/fs/supermount/subfs
MOUNTS=/proc/mounts
TESTMOUNT=/tmp/testmount

#
# Module location
#
KERNEL=`uname -r`
MODULE_DIR=/lib/modules/$KERNEL
USB_MODMAP=$MODULE_DIR/modules.usbmap
LTSP_USB_MODMAP=/etc/usblist

#
# Set environment and exit upon failure
#

if [ ! -d $HOTPLUGDIR ] ; then
  exit 0
fi

if [ ! -d $TESTMOUNT ]; then
  mkdir $TESTMOUNT || exit 1
fi

grep usbdevfs $MOUNTS >/dev/null 2>&1
if [ "$?" != 0 ]; then
  mount -t usbdevfs none /proc/bus/usb
  if [ "$?" != 0 ]; then
    exit 1
  fi
fi

#######################
#      Functions      #
#######################

deviceInfo() {
  THISFILE=$1
  # Gather info about devices
  hostArray=`grep Host $THISFILE|cut -d" " -f2`
  busArray=`grep Host $THISFILE|cut -d" " -f4`
  targetArray=`grep Host $THISFILE|cut -d" " -f6`
  lunArray=`grep Host $THISFILE|cut -d" " -f8`
                                                                                
  j=0
  devices=
  for i in $hostArray; do
    thisbus=`echo $busArray|cut -d" " -f$(( ${j} + 1 ))`
    thistarget=`echo $targetArray|cut -d" " -f$(( ${j} + 1 ))`
    thislun=`echo $lunArray|cut -d" " -f$(( ${j} + 1 ))`
    devices="$devices /dev/scsi/host${i/scsi/}/bus$(($thisbus%100))/target$(($thistarget))/lun$(($thislun))"
    j=$(( ${j} + 1 ))
  done
  echo $devices
}

mount_device_num()
{
  DEVNUM=$1
  SCSI_DIR=$2
  mkdir ${HOTPLUGDIR}/host${DEVNUM}
 
  #SCSI_DIR=/dev/scsi/host${DEVNUM}/bus0/target0/lun0
 
  PRODUCT_NAME=`grep Product /proc/scsi/usb-storage-${DEVNUM}/${DEVNUM} | \
                sed -e 's/.*: //' | tr ' ' '_'`
                                                                                
  MODEL=`grep -h -s "^${PRODUCT_NAME}" /etc/devname_map.local /etc/devname_map|\         head -1 | sed 's/      / /g' | tr -s ' ' | cut -d' ' -f 2`
                                                                                
  [ -n "${MODEL}" ] && PRODUCT_NAME="${MODEL}"
                                                                                
  COUNT=1
  while [ -L ${DRIVESDIR}/${PRODUCT_NAME}_${COUNT} ]; do
    COUNT=`expr $COUNT + 1`
  done
                                                                                
  LINK_NAME=${PRODUCT_NAME}_${COUNT}
                                                                                
  if [ -b $SCSI_DIR/part1 ] ; then
     mount $SCSI_DIR/part1 $TESTMOUNT
     if [ "$?" != 0 ]; then
       umount $TESTMOUNT
     else
       umount $TESTMOUNT
       echo "${DRIVESDIR}/${LINK_NAME}" >${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME
       mount -t supermount \
         -o fs=vfat:msdos:iso9660:ext2,dev=$SCSI_DIR/part1,--,rw,uid=99,gid=99 \
         none $HOTPLUGDIR/host${DEVNUM}
       cd $HOTPLUGDIR/host${DEVNUM}
       ln -s `basename $HOTPLUGDIR`/host${DEVNUM} "${DRIVESDIR}/${LINK_NAME}"
       return
     fi
  fi
  if [ -b $SCSI_DIR/cd ] ; then
     echo "${DRIVESDIR}/${LINK_NAME}" >${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME
     mount -t supermount \
       -o fs=vfat:msdos:iso9660:ext2,dev=$SCSI_DIR/cd,--,ro,uid=99,gid=99 \
       none $HOTPLUGDIR/host${DEVNUM}
     cd $HOTPLUGDIR/host${DEVNUM}
     ln -s `basename $HOTPLUGDIR`/host${DEVNUM} "${DRIVESDIR}/${LINK_NAME}"
     return
  fi
  if [ -b $SCSI_DIR/disc ] ; then
     echo "${DRIVESDIR}/${LINK_NAME}" >${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME
     mount -t supermount \
       -o fs=vfat:msdos:iso9660:ext2,dev=$SCSI_DIR/disc,--,rw,uid=99,gid=99 \
       none $HOTPLUGDIR/host${DEVNUM}
     cd $HOTPLUGDIR/host${DEVNUM}
     ln -s `basename $HOTPLUGDIR`/host${DEVNUM} "${DRIVESDIR}/${LINK_NAME}"
     return
  fi
}

umount_device_num()
{
  DEVNUM=$1
  if [ -d ${HOTPLUGDIR}/host${DEVNUM} ] ; then
    umount -l ${HOTPLUGDIR}/host${DEVNUM}
    if [ -f ${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME ]; then
      rm -f `cat ${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME`
      rm ${HOTPLUGDIR}/host${DEVNUM}/LINK_NAME
    fi
    rmdir ${HOTPLUGDIR}/host${DEVNUM}
  fi
}

device_disconnected() {
  k=$1
  USBDEV="/proc/scsi/usb-storage-${k}/${k}"
  if [ -f ${USBDEV} ] ; then
    grep "Attached: Yes" $USBDEV > /dev/null
    echo $?
  fi
}

#######################
#   Module Functions  #
#######################

add_usbstorage() {
  proc_devices=`deviceInfo $PROCSCSI`

  # Supermount this device
  # If the device is attached but is not supermounted:
  count=0
  for k in $proc_devices; do
    DEVICE_DISCONNECTED=`device_disconnected $count`
    grep $k $SUPERMOUNTS >/dev/null 2>&1
    if [ "$?" != 0 -a "$DEVICE_DISCONNECTED" != 1 ]; then
      # I am connected and not supermounted
      echo "$k not found in $SUPERMOUNTS"
      mount_device_num $count $k
    fi
    count=$(($count + 1))
  done
}

remove_usbstorage() {
  proc_devices=`deviceInfo $PROCSCSI`

  # If the device is in supermount and unmounted, 
  # remove the supermount for this device
  count=0
  for k in $proc_devices; do
    DEVICE_DISCONNECTED=`device_disconnected $count`
    grep $k $SUPERMOUNTS >/dev/null 2>&1
    if [ "$?" == 0 -a "$DEVICE_DISCONNECTED" == 1 ]; then
      # This will trigger a removal
      umount_device_num $count
    fi
    count=$(($count + 1))
  done 
}


#######################
#        Main         #
#######################

#
# ADD event
#
                                                                                
if [ "$ACTION" == "add" ] ; then

  #
  # USB add event
  #
                                                                                
  if [ "$DEVFS" == "/proc/bus/usb" ] ; then

     #
     # Get vendor and product ID, and find them in the module map
     #
                                                                                
     ID_VENDOR=`echo $PRODUCT | cut -d'/' -f 1`
     ID_PRODUCT=`echo $PRODUCT | cut -d'/' -f 2`
     #MODULE=`grep -h $ID_VENDOR $LTSP_USB_MODMAP $USB_MODMAP | grep $ID_PRODUCT | cut -d' ' -f 1 | head -1`
     # Below is an updated usblist parser, which should be more accurate
     MODULE=`cat $LTSP_USB_MODMAP $USB_MODMAP|sed -e 's/x\(0\)\+/x/g' -e 's/x /x0/g' -e 's/x$/x0/' -e 's/\([[:blank:]]\)\+/ /g'|grep "0x$ID_VENDOR 0x$ID_PRODUCT"| cut -d' ' -f 1 | head -1`

     MODULE=${MODULE:-"usb-storage"}

     lsmod | grep $MODULE > /dev/null
     if [ $? -eq 1 ] ; then
       modprobe $MODULE
     fi
 
     # This next part *should* be in modules.dep, but...
     if [ "$MODULE" == "usb-storage" ] ; then
       lsmod | grep "s[dr]_mod" > /dev/null
       if [ $? -eq 1 ] ; then
         modprobe sd_mod && modprobe sr_mod
       fi
     fi

     add_${MODULE/-/} 2>/dev/null

  fi #end is USB device

#
# REMOVE action
#
                                                                                
elif [ "$ACTION" == "remove" ] ; then
                                                                                
  if [ "$DEVFS" == "/proc/bus/usb" ] ; then

     #
     # Get vendor and product ID, and find them in the module map
     #
                                                                                
     ID_VENDOR=`echo $PRODUCT | cut -d'/' -f 1`
     ID_PRODUCT=`echo $PRODUCT | cut -d'/' -f 2`
     #MODULE=`grep -h $ID_VENDOR $LTSP_USB_MODMAP $USB_MODMAP | grep $ID_PRODUCT | cut -d' ' -f 1 | head -1`
     # Below is an updated usblist parser, which should be more accurate
     MODULE=`cat $LTSP_USB_MODMAP $USB_MODMAP|sed -e 's/x\(0\)\+/x/g' -e 's/x /x0/g' -e 's/x$/x0/' -e 's/\([[:blank:]]\)\+/ /g'|grep "0x$ID_VENDOR 0x$ID_PRODUCT"| cut -d' ' -f 1 | head -1`
                                                                                
     MODULE=${MODULE:-"usb-storage"}

     remove_${MODULE/-/} 2>/dev/null
     rmmod $MODULE 2>/dev/null
   
  fi # end is USB device

fi