Ticket #600: start_udev-RHEL-5.7

#!/bin/sh
#
# start_udev
#
# script to initialize /dev by using udev.
#
# Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
#
# Released under the GPL v2 only.
#
# This needs to be run at the earliest possible point in the boot 
# process.
#
# Based on the udev init.d script
#
# Thanks go out to the Gentoo developers for proving 
# that this is possible to do.
#
# Yes, it's very verbose, feel free to turn off all of the echo calls,
# they were there to make me feel better that everything was working
# properly during development...
#
# don't use udev if sysfs is not mounted.

sysfs_dir=/sys

export TZ=/etc/localtime

[ -d $sysfs_dir/class ] || exit 1
[ -r /proc/mounts ] || exit 1
[ -x /sbin/udevd ] || exit 1
[ -f /etc/udev/udev.conf ] && . /etc/udev/udev.conf
udev_root=${udev_root-/dev}


. /etc/init.d/functions

umask 0022

prog=udev
bin=/sbin/udev
udevd=/sbin/udevd
MAKEDEV="/sbin/MAKEDEV"

xargs_simple () {
    if [ "$1" = "-n" ]; then
        shift
        MAXNR="$1"
        shift
    else
        MAXNR=100
    fi
    NR=$MAXNR
    ARGS=""
    [ -z "$1" ] && set echo

    while read line; do
        if [ $NR -gt 0 ]; then
                ARGS="$ARGS $line"
                NR=$[$NR - 1]
        else
                "$@" $ARGS
                NR=$MAXNR
                ARGS="$line"
        fi
    done
    if [ -n "$ARGS" ]; then
        "$@" $ARGS
    fi 
}

make_extra_nodes () {
    ln -snf /proc/self/fd $udev_root/fd
    ln -snf /proc/self/fd/0 $udev_root/stdin
    ln -snf /proc/self/fd/1 $udev_root/stdout
    ln -snf /proc/self/fd/2 $udev_root/stderr
    ln -snf /proc/kcore $udev_root/core

    [ -d $udev_root/pts ] || mkdir -m 0755 $udev_root/pts
    [ -d $udev_root/shm ] || mkdir -m 0755 $udev_root/shm
    [ -a /dev/MAKEDEV ] || ln -s $MAKEDEV /dev/MAKEDEV;

    if [ -x $MAKEDEV ]; then
        for i in /etc/udev/makedev.d/*.nodes; do
            if [ -f "$i" ]; then 
                cat "$i" | sed -e 's,#.*,,g' | \
                    xargs_simple -n 100 $MAKEDEV -x
            fi
        done 
    fi
    for devdir in /etc/udev/devices /lib/udev/devices; do
        [ -d "$devdir" ] || continue
        pushd $devdir &> "$udev_root/null"
        set *
        if [ "$1" != "*" ]; then
                cp -ar "$@" $udev_root/ 
            pushd "$udev_root" &> "$udev_root/null"
            [ -x /sbin/restorecon ] && /sbin/restorecon "$@" 
            popd &> "$udev_root/null"
        fi
        popd &> "$udev_root/null"
    done
}

kill_udevd() {
    if [ -x /sbin/pidof ]; then
        pid=`/sbin/pidof -x udevd`
            [ -n "$pid" ] && kill $pid
    fi
}


wait_for_queue() {
        local timeout=${1:-0}
    local ret=0
    if [ $timeout -gt 0 ]; then
        /sbin/udevsettle --timeout=$timeout
        else
        /sbin/udevsettle
    fi
    ret=$?
    if [ $ret -ne 0 ]; then
        echo -n "Wait timeout. Will continue in the background."
    fi
    return $ret;
}

export ACTION=add
prog=udev
ret=0
STRING=$"Starting $prog: "
# propagate $udev_root from /sys
echo -n "$STRING"

# mount the tmpfs on ${udev_root%/}, if not already done
LANG=C awk "\$2 == \"${udev_root%/}\" && \$3 == \"tmpfs\" { exit 1 }" /proc/mounts && {
    if LANG=C fgrep -q "none ${udev_root%/}/pts " /proc/mounts; then
        PTSDIR=$(mktemp -d)
        mount --move $udev_root/pts "$PTSDIR"
    fi
    if LANG=C fgrep -q "none ${udev_root%/}/shm " /proc/mounts; then
        SHMDIR=$(mktemp -d)
        mount --move $udev_root/shm "$SHMDIR"
    fi
    mount -n -o mode=0755 -t tmpfs none "$udev_root"
    mkdir -m 0755 $udev_root/pts
    mkdir -m 0755 $udev_root/shm
    if [ -n "$PTSDIR" ]; then
        mount --move "$PTSDIR" $udev_root/pts
        rmdir "$PTSDIR"
    fi
    if [ -n "$SHMDIR" ]; then
        mount --move "$SHMDIR" $udev_root/shm
        rmdir "$SHMDIR"
    fi
    
    ret=$[$ret + $?]
}

# returns OK if $1 contains $2
strstr() {
  [ "${1#*$2*}" = "$1" ] && return 1
  return 0
}

getval() {
    what=$1
    shift
    for arg; do 
    if strstr "$arg" "$what="; then
        val=${arg#${what}=*}
        echo $val
        return 0
    fi
    done
    return 1
}


make_extra_nodes

kill_udevd > "$udev_root/null" 2>&1

rm -fr /dev/.udev  > "$udev_root/null" 2>&1

cmdline=$(cat /proc/cmdline)

if [ -f "/sys/class/tty/console/uevent" ]; then
    # trigger the sorted events
    echo -e '\000\000\000\000' > /proc/sys/kernel/hotplug
    if strstr "$cmdline" modprobedebug; then
        touch /dev/.modprobe_debug
    else
        rm -f /dev/.modprobe_debug
    fi
    /sbin/udevd -d
    ret=$[$ret + $?]
    if strstr "$cmdline" udevdebug; then
        /sbin/udevcontrol log_priority=debug
    fi
    /sbin/udevtrigger
    ret=$[$ret + $?]
    wait_for_queue $(getval udevtimeout $cmdline)
    ret=$[$ret + $?]
else
    echo -n " kernel too old for this udev version "
    /sbin/udevd -d
    ret=10
fi

ret=$[$ret + $?]
[ $ret -eq 0 ] && success $"$STRING" || failure $"$STRING"
echo
exit 0