RUNSCRIPT¶

NAME¶

runscript - a means of hooking shell commands into a service

SYNOPSIS¶

runscript [-D , -nodeps ] [-d , -debug ] [-s , -ifstarted ] [-Z , -dry-run ] [command ... ]

DESCRIPTION¶

runscript is basically an interpreter for shell scripts which provide an easy interface to the often complex system commands and daemons. When a service runs a command it first loads its multiplexed configuration file, then its master configuration file, then /etc/rc.conf and finally the script itself. At this point runscript then runs the command given.

Commands are defined as shell functions within the script. Here is a list of some functions that all runscripts have by default:

describe

Describes what the service does and each command the service defines.

start

First we ensure that any services we depend on are started. If any needed services fail to start then we exit with a suitable error, otherwise call the supplied start function if it exists.

stop

First we ensure that any services that depend on us are stopped. If any services that need us fail to stop then we exit with a suitable error, otherwise call the supplied stop function if it exists.

restart

Stop and start the service, including dependencies.

status

Show the status of the service. The return code matches the status, with the exception of "started" returning 0 to match standard command behaviour.

zap

Resets the service state to stopped and removes all saved data about the service.

The following options affect how the service is run:

-d , -debug

Set xtrace on in the shell to assist in debugging.

-D , -nodeps

Ignore all dependency information the service supplies.

-s , -ifstarted

Only run the command if the service has been started.

-q , -quiet

Turns off all informational output the service generates. Output from any non OpenRC commands is not affected.

-v , -verbose

Turns on any extra informational output the service generates.

-Z , -dry-run

Shows what services would be stopped and/or started without actually starting or stopping them.

The following variables affect the service script:

extra_commands

Space separated list of extra commands the service defines.

extra_started_commands

Space separated list of extra commands the service defines. These only work if the service has already been started.

description

String describing the service.

description_$command

String describing the extra command the.

command

Daemon to start or stop via start-stop-daemon if no start or stop function is defined by the service.

command_args

List of arguments to pass to the daemon when starting.

pidfile

Pidfile to use for the above defined command.

name

Display name used for the above defined command.

DEPENDENCIES¶

You should define a depend function for the service so that runscript will start and stop it in the right order in relation to other services. As it's a function it can be very flexible, see the example below. Here is a list of the functions you can use in a depend function. You simply pass the names of the services to it to add to that dependency type, or prefix it with ! to remove it.

need

The service will refuse to start until needed services have started and it will refuse to stop until any services that need it have stopped.

use

The service will attempt to start any services we use that have been added to the runlevel.

after

The service will start after these services and stop before these services.

before

The service will start before these services and stop after these services.

provide

We provide this virtual service. For example, named provides dns.

config

We should recalculate our dependencies if the listed files have changed.

keyword

Tags a service with a keyword. Here's the keywords we currently understand:-

-shutdown

Don't stop this service when shutting the system down. This normally quite safe as remaining daemons will be sent a SIGTERM just before final shutdown. Network related services such as the network and dhcpcd init scripts normally have this keyword.

-stop

Don't stop this service when changing runlevels, even if not present. This includes shutting the system down.

-timeout

Other services should wait indefinitely for this service to start. Use this keyword if your service may take longer than 60 seconds to start.

-jail

When in a jail, exclude this service from any dependencies. The service can still be run directly. Set via rc_sys in /etc/rc.conf

-lxc

Same as -jail, but for Linux Resource Containers (LXC).

-openvz

Same as -jail, but for OpenVZ systems.

-prefix

Same as -jail, but for Prefix systems.

-uml

Same as -jail, but for UML systems.

-vserver

Same as -jail, but for VServer systems.

-xen0

Same as -jail, but for Xen DOM0 systems.

-xenu

Same as -jail, but for Xen DOMU systems.

To see how to influence dependencies in configuration files, see the FILES section below.

BUILTINS¶

runscript defines some builtin functions that you can use inside your service scripts:

einfo [string ]

Output a green asterisk followed by the string.

ewarn [string ]

Output a yellow asterisk followed by the string.

eerror [string ]

Output a red asterisk followed by the string to stderr.

ebegin [string ]

Same as einfo, but append 3 dots to the end.

eend retval [string ]

If retval does not equal 0 then output the string using eerror and !! in square brackets at the end of the line. Otherwise output ok in square brackets at the end of the line. The value of retval is returned.

ewend retval [string ]

Same as eend, but use ewarn instead of eerror.

You can prefix the above commands with the letter v, which means they only output when the environment variable EINFO_VERBOSE is true.

ewaitfile timeout file1 file2 ...

Wait for timeout seconds until all files exist. Returns 0 if all files exist, otherwise non zero. If timeout is less then 1 then we wait indefinitely.

is_newer_than file1 file2 ...

If file1 is newer than file2 return 0, otherwise 1. If file2 is a directory, then check all its contents too.

is_older_than file1 file2 ...

If file1 is newer than file2 return 0, otherwise 1. If file2 is a directory, then check all its contents too.

service_set_value name value

Saves the name value for later retrieval. Saved values are lost when the service stops.

service_get_value name

Returns the saved value called name.

service_started [service ]

If the service is started, return 0 otherwise 1.

service_starting [service ]

If the service is starting, return 0 otherwise 1.

service_inactive [service ]

If the service is inactive, return 0 otherwise 1.

service_stopping [service ]

If the service is stopping, return 0 otherwise 1.

service_stopped [service ]

If the service is stopped, return 0 otherwise 1.

service_coldplugged [service ]

If the service is coldplugged, return 0 otherwise 1.

service_wasinactive [service ]

If the service was inactive, return 0 otherwise 1.

service_started_daemon

[service ] daemon [index ] &infin; start-stop-daemon, return 0 otherwise 1. If an index is specified, it has to be the nth daemon started by the service.

mark_service_started [service ]

Mark the service as started.

mark_service_starting [service ]

Mark the service as starting.

mark_service_inactive [service ]

Mark the service as inactive.

mark_service_stopping [service ]

Mark the service as stopping.

mark_service_stopped [service ]

Mark the service as stopped.

mark_service_coldplugged [service ]

Mark the service as coldplugged.

mark_service_wasinactive [service ]

Mark the service as inactive.

checkpath

[-d , -directory ] [-f , -file ] [-m , -mode mode ] [-o , owner owner ] path ... Checks to see if the path exists, is of the right type, owned by the right people and has the correct access modes. If not, then it corrects the path.

yesno value

If value matches YES, TRUE, ON or 1 regardless of case then we return 0, otherwise 1.

ENVIRONMENT¶

runscript sets the following environment variables for use in the service scripts:

RC_SVCNAME

Name of the service.

RC_RUNLEVEL

Current runlevel that rc is in.

RC_BOOTLEVEL

Boot runlevel chosen. Default is boot.

RC_DEFAULTLEVEL

Default runlevel chosen. Default is default.

RC_SYS

A special variable to describe the system more. Possible values are OPENVZ, XENU, XEN0, UML and VSERVER.

RC_UNAME

The result of `uname -s`.

FILES¶

Configuration files, relative to the location of the service. If a file ending with .${RC_RUNLEVEL} exists then we use that instead.

../conf.d/${RC_SVCNAME%%.*}

multiplexed configuration file. Example: if ${RC_SVCNAME} is net.eth1 then look for ../conf.d/net.

../conf.d/${RC_SVCNAME}

service configuration file.

/etc/rc.conf

host configuration file.

With the exception of /etc/rc.conf, the configuration files can also influence the dependencies of the service through variables. Simply prefix the name of the dependency with rc_. Examples:

# Whilst most services don't bind to a specific interface, our
# openvpn configuration requires a specific interface, namely bge0.
rc_need="net.bge0" 
# To put it in /etc/rc.conf you would do it like this
rc_openvpn_need="net.bge0" 

# Services should not depend on the tap1 interface for network,
# but we need to add net.tap1 to the default runlevel to start it.
rc_provide="!net" 
# To put it in /etc/conf.d/net you would do it like this
rc_provide_tap1="!net" 
# To put in in /etc/rc.conf you would do it like this
rc_net_tap1_provide="!net" 

# It's also possible to negate keywords. This is mainly useful for prefix
# users testing OpenRC.
rc_keyword="!noprefix"

EXAMPLES¶

An example service script for foo.

#!/sbin/runscript
command=/usr/bin/foo
command_args="${foo_args} --bar" 
pidfile=/var/run/foo.pid
name="FooBar Daemon" 

description="FooBar is a daemon that eats and drinks" 
extra_commands="show" 
extra_started_commands="drink eat" 
description_drink="Opens mouth and reflexively swallows" 
description_eat="Chews food in mouth" 
description_show="Shows what's in the tummy" 

_need_dbus()
{
    grep -q dbus /etc/foo/plugins
}

depend()
{
    # We write a pidfile and to /var/cache, so we need localmount.
    need localmount
    # We can optionally use the network, but it's not essential.
    use net
    # We should be after bootmisc so that /var/run is cleaned before
    # we put our pidfile there.
    after bootmisc

    # Foo may use a dbus plugin.
    # However, if we add the dbus plugin whilst foo is running and
    # stop dbus, we don't need to stop foo as foo didn't use dbus.
    config /etc/foo/plugins
    local _need=
    if service_started; then
        _need=`service_get_value need`
    else
        if _need_dbus; then
           _need="${_need} dbus" 
        fi
    fi
    need ${_need}
}

start_pre()
{
    # Ensure that our dirs are correct
    checkpath --dir --owner foo:foo --mode 0664 \
        /var/run/foo /var/cache/foo
}

start_post()
{
    # Save our need
    if _need_dbus; then
        service_set_value need dbus
    fi
}

stop_post() {
    # Clean any spills
    rm -rf /var/cache/foo/*
}

drink()
{
    ebegin "Starting to drink" 
    ${command} --drink beer
    eend $? "Failed to drink any beer :(" 
}

eat()
{
    local result=0 retval= ate= food=
    ebegin "Starting to eat" 

    if yesno "${foo_diet}"; then
        eend 1 "We are on a diet!" 
        return 1
    fi

    for food in /usr/share/food/*; do
        veinfo "Eating `basename ${food}`" 
        ${command} --eat ${food}
        retval=$?
        : $((${result} += ${retval}))
        [ ${retval} = 0 ] && ate="${ate} `basename ${food}`" 
    done

    if eend ${result} "Failed to eat all the food"; then
        service_set_value ate "${ate}" 
    fi
}

show()
{
    einfo "Foo has eaten: `service_get_value ate`" 
}

BUGS¶

Because of the way we load our configuration files and the need to handle more than one service directory, you can only use symlinks in service directories to other services in the same directory. You cannot symlink to a service in a different directory even if it is another service directory.

is_older_than should return 0 on success. Instead we return 1 to be compliant with Gentoo baselayout. Users are encouraged to use the is_newer_than function which returns correctly.

AUTHORS¶

Roy Marples <roy@marples.name>