poky/meta/recipes-core/initrdscripts/initramfs-framework/init

#!/bin/sh

Copyright (C) 2011 O.S. Systems Software LTDA.

Licensed on MIT

Provides the API to be used by the initramfs modules

Modules need to provide the following functions:

_enabled : check if the module ought to run (return 1 to skip)

_run : do what is need

Boot parameters are available on environment in the as:

'foo=value' as 'bootparam_foo=value'

'foo' as 'bootparam_foo=true'

'foo.bar[=value] as 'foo_bar=[value|true]'

Register a function to be called before running a module

The hook is called as:

pre

add_module_pre_hook() { MODULE_PRE_HOOKS="$MODULE_PRE_HOOKS $1" }

Register a function to be called after running a module

The hook is called as:

post

add_module_post_hook() { MODULE_POST_HOOKS="$MODULE_POST_HOOKS $1" }

Load kernel module

load_kernel_module() { if modprobe $1 >/dev/null 2>&1; then info "Loaded module $1" else debug "Failed to load module $1" fi }

Prints information

msg() { echo "$@" >/dev/console }

Prints information if verbose bootparam is used

info() { [ -n "$bootparam_verbose" ] && echo "$@" >/dev/console }

Prints information if debug bootparam is used

debug() { [ -n "$bootparam_debug" ] && echo "DEBUG: $@" >/dev/console }

Prints a message and start a endless loop

fatal() { echo $1 >/dev/console echo >/dev/console

if [ -n "$bootparam_init_fatal_sh" ]; then
    sh
else
while [ "true" ]; do
	sleep 3600
done
fi

}

Variables shared amoung modules

ROOTFS_DIR="/rootfs" # where to do the switch root MODULE_PRE_HOOKS="" # functions to call before running each module MODULE_POST_HOOKS="" # functions to call after running each module MODULES_DIR=/init.d # place to look for modules EFI_DIR=/sys/firmware/efi # place to store device firmware information

make mount stop complaining about missing /etc/fstab

touch /etc/fstab

initialize /proc, /sys, /run/lock and /var/lock

mkdir -p /proc /sys /run/lock /var/lock mount -t proc proc /proc mount -t sysfs sysfs /sys

if [ -d $EFI_DIR ];then mount -t efivarfs none /sys/firmware/efi/efivars fi

populate bootparam environment

for p in cat /proc/cmdline; do opt=echo $p | cut -d'=' -f1 opt=echo $opt | sed -e 'y/.-/__/' if [ "echo $p | cut -d'=' -f1" = "$p" ]; then eval "bootparam_${opt}=true" else value="echo $p | cut -d'=' -f2-" eval "bootparam_${opt}="${value}"" fi done

use /dev with devtmpfs

if grep -q devtmpfs /proc/filesystems; then mkdir -p /dev mount -t devtmpfs devtmpfs /dev else if [ ! -d /dev ]; then fatal "ERROR: /dev doesn't exist and kernel doesn't has devtmpfs enabled." fi fi

mkdir $ROOTFS_DIR

Load and run modules

for m in $MODULES_DIR/*; do # Skip backup files if [ "echo $m | sed -e 's/\~$//'" != "$m" ]; then continue fi

module=`basename $m | cut -d'-' -f 2`
debug "Loading module $module"

# pre hooks
for h in $MODULE_PRE_HOOKS; do
	debug "Calling module hook (pre): $h"
	eval "$h pre $module"
	debug "Finished module hook (pre): $h"
done

# process module
. $m

if ! eval "${module}_enabled"; then
	debug "Skipping module $module"
	continue
fi

debug "Running ${module}_run"
eval "${module}_run"

# post hooks
for h in $MODULE_POST_HOOKS; do
	debug "Calling module hook (post): $h"
	eval "$h post $module"
	debug "Finished module hook (post): $h"
done

done

Catch all

fatal "ERROR: Initramfs failed to initialize the system."