mountsshfs with addition of MOUNT_AS variable

mountsshfs

#!/bin/sh

## http://ubuntuforums.org/showthread.php?t=430312
## The script will attempt to mount any fstab entry with an option
## "...,comment=$SELECTED_STRING,..."
## Use this to select specific sshfs mounts rather than all of them.
SELECTED_STRING="sshfs"

## mount as user, default = "root"
MOUNT_AS="root"

# Not for loopback
[ "$IFACE" != "lo" ] || exit 0

## define a number of useful functions

## returns true if input contains nothing but the digits 0-9, false otherwise
## so realy, more like isa_positive_integer 
isa_number () {
    ! echo $1 | egrep -q '[^0-9]'
    return $?
}

## returns true if the given uid or username is that of the current user
am_i () {
  [ "$1" = "`id -u`" ] || [ "$1" = "`id -un`" ]
}

## takes a username or uid and finds it in /etc/passwd
## echoes the name and returns true on success
## echoes nothing and returns false on failure 
user_from_uid () {
    if isa_number "$1"
    then
		# look for the corresponding name in /etc/passwd
    	local IFS=":"
    	while read name x uid the_rest
    	do
        	if [ "$1" = "$uid" ]
			then 
				echo "$name"
				return 0
			fi
    	done </etc/passwd
    else
    	# look for the username in /etc/passwd
    	if grep -q "^${1}:" /etc/passwd
    	then
    		echo "$1"
    		return 0
    	fi
    fi
    # if nothing was found, return false
   	return 1
}

## Parses a string of comma-separated fstab options and finds out the 
## username/uid assigned within them. 
## echoes the found username/uid and returns true if found
## echoes "root" and returns false if none found
uid_from_fs_opts () {
	local uid=`echo $1 | egrep -o 'uid=[^,]+'`
	if [ -z "$uid" ]; then
		# no uid was specified, so default is root
		echo "root"
		return 1
	else
		# delete the "uid=" at the beginning
		uid_length=`expr length $uid - 3`
		uid=`expr substr $uid 5 $uid_length`
		echo $uid
		return 0
	fi
}

# unmount all shares first
sh "/etc/network/if-down.d/umountsshfs"

while read fs mp type opts dump pass extra
do
    # check validity of line
    if [ -z "$pass" -o -n "$extra" -o "`expr substr ${fs}x 1 1`" = "#" ]; 
    then
        # line is invalid or a comment, so skip it
        continue
    
    # check if the line is a selected line
    elif echo $opts | grep -q "comment=$SELECTED_STRING"; then
        sudo -u $MOUNT_AS sh -c "mount $mp" &&
        echo "$mp mounted as $MOUNT_AS" ||
        echo "$mp failed to mount as $MOUNT_AS";
    fi
    # if not an sshfs line, do nothing
done </etc/fstab

wait