source: trunk/minix/commands/scripts/adduser.sh@ 21

#!/bin/sh
#
#       adduser 1.0 - add a new user to the system      Author: Kees J. Bot
#                                                               16 Jan 1996

# Check arguments.
case "$#" in
3)      user="$1"; group="$2"; home="$3"
        ;;
*)      echo "Usage: adduser user group home-dir" >&2; exit 1
esac

# We need to be root.
case "`id`" in
'uid=0('*)
        ;;
*)      echo "adduser: you must be root to add users" >&2; exit 1
esac

# User and group names must be alphanumeric and no longer than 8 characters.
len=`expr "$user" : '[a-z][a-z0-9]*$'`
if [ "$len" -eq 0 -o "$len" -gt 8 ]
then
        echo >&2 \
"adduser: the user name must be alphanumeric and no longer than 8 characters"
        exit 1
fi

len=`expr "$group" : '[a-z][a-z0-9]*$'`
if [ "$len" -eq 0 -o "$len" -gt 8 ]
then
        echo >&2 \
"adduser: the group name must be alphanumeric and no longer than 8 characters"
        exit 1
fi

# The new user name must not exist, but the group must exist.
if grep "^$user:" /etc/passwd >/dev/null
then
        echo "adduser: user $user already exists" >&2
        exit 1
fi

gid=`sed -e "/^$group:/!d" -e 's/^[^:]*:[^:]*:\\([^:]*\\):.*/\\1/' /etc/group`
if [ `expr "$gid" : '[0-9]*$'` -eq 0 ]
then
        echo "adduser: group $group does not exist" >&2
        exit 1
fi

# Find the first free user-id of 10 or higher.
uid=10
while grep "^[^:]*:[^:]*:$uid:.*" /etc/passwd >/dev/null
do
        uid=`expr $uid + 1`
done

# No interruptions.
trap '' 1 2 3 15

# Lock the password file.
ln /etc/passwd /etc/ptmp || {
        echo "adduser: password file busy, try again later"
        exit 1
}

# Make the new home directory, it should not exist already.
mkdir "$home" || {
        rm -rf /etc/ptmp
        exit 1
}

# Make the new home directory by copying the honorary home directory of our
# fearless leader.
echo cpdir /usr/ast "$home"
cpdir /usr/ast "$home" || {
        rm -rf /etc/ptmp "$home"
        exit 1
}

# Change the ownership to the new user.
echo chown -R $uid:$gid "$home"
chown -R $uid:$group "$home" || {
        rm -rf /etc/ptmp "$home"
        exit 1
}

# Is there a shadow password file?  If so add an entry.
if [ -f /etc/shadow ]
then
        echo "echo $user::0:0::: >>/etc/shadow"
        echo "$user::0:0:::" >>/etc/shadow || {
                rm -rf /etc/ptmp "$home"
                exit 1
        }
        pwd="##$user"
else
        pwd=
fi

# Finish up by adding a password file entry.
echo "echo $user:$pwd:$uid:$gid:$user:$home: >>/etc/passwd"
echo "$user:$pwd:$uid:$gid:$user:$home:" >>/etc/passwd || {
        rm -rf /etc/ptmp "$home"
        exit 1
}

# Remove the lock.
rm /etc/ptmp || exit

echo "
The new user $user has been added to the system.  Note that the password,
full name, and shell may be changed with the commands passwd(1), chfn(1),
and chsh(1).  The password is now empty, so only console logins are possible."
if [ $gid = 0 ]
then
        echo "\
Also note that a new operator needs an executable search path (\$PATH) that
does not contain the current directory (an empty field or "." in \$PATH)."
fi
exit 0