#!/bin/bash
#
# $Id: rescanscsi,v 1.2 2001/02/20 06:35:56 merlin Exp $
#
# $Log: rescanscsi,v $
# Revision 1.2  2001/02/20 06:35:56  merlin
# Now remove devices too
#
# Revision 1.1  1998/05/24 05:23:41  merlin
# First version checked in CVS
#
#
# Skript to rescan SCSI bus, using the 
# scsi add-single-device mechanism     
# (w) 98/03/19 Kurt Garloff <K.Garloff@ping.de> (c) GNU GPL
                                                           
# Return hosts. /proc/scsi/HOSTADAPTER/? must exist        
findhosts ()                                               
{
  hosts=
  for name in /proc/scsi/*/?; do
    name=${name#/proc/scsi/}    
    if test ! $name = scsi      
      then hosts="$hosts ${name#*/}"
      echo "Host adapter ${name#*/} (${name%/*}) found."
    fi                                                  
  done                                                  
}
 
# Test if SCSI device $host $channen $id $lun exists
# Outputs description from /proc/scsi/scsi, returns new
testexist ()                                           
{
  grepstr="scsi$host Channel: 0$channel Id: 0*$id Lun: 0$lun"
  new=`cat /proc/scsi/scsi|grep -e"$grepstr"`                
  if test ! -z "$new"                                        
    then cat /proc/scsi/scsi|grep -e"$grepstr"                                  
    cat /proc/scsi/scsi|grep -A2 -e"$grepstr"|tail -2|pr -o4 -l1                
  fi                                                                            
}
 
# Perform search (scan $host)
dosearch ()                  
{
  for channel in $channelsearch; do
    for id in $idsearch; do
      for lun in $lunsearch; do
        new=                   
        devnr="$host $channel $id $lun"
        echo "scsi remove-single-device $devnr" >/proc/scsi/scsi
        echo "Scanning for device $devnr ..."
        printf "OLD: "
        testexist     
        if test -z "$new"
          then printf "\rNEW: "
          echo "scsi add-single-device $devnr" >/proc/scsi/scsi
          testexist                                            
          if test -z "$new"; then printf "\r\x1b[A"; else let found+=1; fi
        fi
      done
    done
  done
}
 
 
# main
if test @$1 = @--help -o @$1 = @-h
  then                            
    echo "Usage: rescan-scsi-bus.sh [-l] [-c] [host [host ...]]"
    echo " -l activates scanning for LUNs 0 .. 7 [default: 0]"
    echo " -c enables scanning of channels 0 1 [default: 0]"
    echo " If hosts are given, only these are scanned [def.: all]"
    exit 0                                                        
fi

# defaults
lunsearch="0"
idsearch="0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15"
channelsearch="0"

# Scan options
opt="$1"      
while test ! -z "$opt" -a -z "${opt##-*}"; do
  opt=${opt#-}                               
  case "$opt" in                             
    l) lunsearch="0 1 2 3 4 5 6 7" ;;        
    c) channelsearch="0 1" ;;        
    *) echo "Unknown option -$opt !" ;;        
  esac                                         
  shift                                        
  opt="$1"                                     
done                                           

# Hosts given ?
if test @$1 = @; then findhosts; else hosts=$*; fi

declare -i found=0
for host in $hosts; do dosearch; done
echo "$found new device(s) found."