#!/bin/sh
#
# Licensed under the GPLv2
#
# Copyright 2008, Red Hat, Inc.
# Jeremy Katz <katzj@redhat.com>

emergency_shell()
{
    source_all emergency
    echo ; echo
    echo "Bug in initramfs /init detected. Dropping to a shell. Good luck!"
    echo
    sh -i
}

export PATH=/sbin:/bin:/usr/sbin:/usr/bin
export TERM=linux
NEWROOT="/sysroot"

trap "emergency_shell" 0

. /lib/dracut-lib.sh

mknod /dev/null c 1 3

# mount some important things
mount -t proc /proc /proc >/dev/null 2>&1
mount -t sysfs /sys /sys >/dev/null 2>&1

if [ ! -c /dev/ptmx ]; then
    if mount -t devtmpfs -omode=0755 udev /dev >/dev/null 2>&1; then
    :; else
	mount -t tmpfs -omode=0755 udev /dev >/dev/null 2>&1 
	# Make some basic devices first, let udev handle the rest
	mknod /dev/null c 1 3
	mknod /dev/ptmx c 5 2
	mknod /dev/console c 5 1
	mknod /dev/kmsg c 1 11
    fi
fi

getarg rdinitdebug && set -x
mkdir /dev/shm
mkdir /dev/pts
mount -t devpts -o gid=5,mode=620 /dev/pts /dev/pts >/dev/null 2>&1

# run scriptlets to parse the command line
getarg 'rdbreak=cmdline' && emergency_shell
source_all cmdline

[ -z "$root" ] && die "No or empty root= argument"
[ -z "$rootok" ] && die "Don't know how to handle 'root=$root'"

# Network root scripts may need updated root= options,
# so deposit them where they can see them (udev purges the env)
{
    echo "root='$root'"
    echo "rflags='$rflags'"
    echo "fstype='$fstype'"
    echo "netroot='$netroot'"
    echo "NEWROOT='$NEWROOT'"
} > /tmp/root.info

# pre-udev scripts run before udev starts, and are run only once.
getarg 'rdbreak=pre-udev' && emergency_shell
source_all pre-udev

# start up udev and trigger cold plugs
udevd --daemon
getarg rdudevinfo && udevadm control --log_priority=info
getarg rdudevdebug && udevadm control --log_priority=debug

source_all pre-trigger

# then the rest
udevadm trigger $udevtriggeropts  >/dev/null 2>&1
udevadm settle --timeout=30 >/dev/null 2>&1

# pre-mount happens before we try to mount the root filesystem,
# and happens once.
getarg 'rdbreak=pre-mount' && emergency_shell
source_all pre-mount
getarg 'rdbreak=mount' && emergency_shell

# mount scripts actually try to mount the root filesystem, and may
# be sourced any number of times. As soon as one suceeds, no more are sourced.
i=0
while :; do
    [ -d "$NEWROOT/proc" ] && break;

    for f in /mount/*.sh; do
       [ -x "$f" ] && . "$f";
       [ "$ROOTFS_MOUNTED" ] && break;
    done

    sleep 0.5
    i=$(($i+1))
    { flock -s 9 ; [ $i -gt 20 ] && emergency_shell; } 9>/.console_lock
done

# pre pivot scripts are sourced just before we switch over to the new root.
getarg 'rdbreak=pre-pivot' && emergency_shell
source_all pre-pivot

# by the time we get here, the root filesystem should be mounted.
# Try to find init.
for i in "$(getarg init=)" /sbin/init /etc/init /init /bin/sh; do
    [ -f "$NEWROOT$i" -a -x "$NEWROOT$i" ] && { INIT="$i"; break; }
done
[ "$INIT" ] || {
    echo "Cannot find init! Please check to make sure you passed"
    echo "a valid root filesystem!  Dropping to a shell."
    emergency_shell
}

getarg rdbreak && emergency_shell
kill $(pidof udevd)

# Clean up the environment
for i in $(export -p); do
    i=${i#declare -x}
    i=${i#export}
    i=${i%%=*}
    [ "$i" = "root" -o "$i" = "PATH" -o "$i" = "HOME" -o "$i" = "TERM" ] || unset $i
done

initargs=""
for x in "$@"; do
    [ "${x%%=*}" = "console" ] && continue
    [ "${x%%=*}" = "BOOT_IMAGE" ] && continue
    [ "${x%%=*}" = "rdbreak" ] && continue
    [ "${x%%=*}" = "rdinitdebug" ] && continue
    [ "${x%%=*}" = "rdudevinfo" ] && continue
    [ "${x%%=*}" = "rdudevdebug" ] && continue
    [ "${x%%=*}" = "rdnetdebug" ] && continue
    [ "${x%%=*}" = "rdcopystate" ] && continue
    initargs="$initargs $x"
done

# Copy state
mkdir /dev/.initramfs/
if getarg rdcopystate; then
    cp /tmp/* /dev/.initramfs/ >/dev/null 2>&1
else
    cp /tmp/net.* /dev/.initramfs/ >/dev/null 2>&1
fi

exec switch_root "$NEWROOT" "$INIT" $initargs || {
    # davej doesn't like initrd bugs
    echo "Something went very badly wrong in the initrd.  Please "
    echo "file a bug against mkinitrd."
    emergency_shell
}
