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.\"
.\" Copyright (c) 2002 M. Warner Losh
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. The name of the author may not be used to endorse or promote products
.\"    derived from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.\" The section on comments was taken from named.conf.5, which has the
.\" following copyright:
.\" Copyright (c) 1999-2000 by Internet Software Consortium
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
.\" ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
.\" OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
.\" CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
.\" DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
.\" PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
.\" ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
.\" SOFTWARE.
.\"
.Dd October 8, 2016
.Dt DEVD.CONF 5
.Os
.Sh NAME
.Nm devd.conf
.Nd configuration file for
.Xr devd 8
.Sh DESCRIPTION
.Ss General Syntax
A
.Xr devd 8
configuration consists of two general features, statements
and comments.
All statements end with a semicolon.
Many statements can contain substatements, which are also
terminated with a semicolon.
.Pp
The following statements are supported:
.Bl -tag -width ".Ic options"
.It Ic attach
Specifies various matching criteria and actions to perform when
a newly attached device matches said criteria.
.It Ic detach
Specifies various matching criteria and actions to perform when
a newly detached device matches said criteria.
.It Ic nomatch
Specifies various matching criteria and actions to perform when
no device driver currently loaded in the kernel claims a (new)
device.
.It Ic notify
Specifies various matching criteria and actions to perform when the kernel
sends an event notification to userland.
.It Ic options
Specifies various options and parameters for the operation of
.Xr devd 8 .
.El
.Pp
Statements may occur in any order in the configuration file, and may be
repeated as often as required.
Further details on the syntax and meaning of each statement and their
substatements are explained below.
.Pp
Each statement, except
.Ic options
has a priority (an arbitrary number) associated with it, where
.Ql 0
is defined as the lowest priority.
If two statements match the same event, only the action of the statement with
highest priority will be executed.
In this way generic statements can be overridden for devices or
notifications that require special attention.
.Pp
The general syntax of a statement is:
.Bd -literal -offset indent
statement priority {
	substatement "value";
	...
	substatement "value";
};
.Ed
.Ss Sub-statements
The following sub-statements are supported within the
.Ic options
statement.
.Bl -tag -width ".Ic directory"
.It Ic directory Qq Ar /some/path ;
Adds the given directory to the list of directories from which
.Xr devd 8
will read all files named "*.conf" as further
configuration files.
Any number of
.Ic directory
statements can be used.
.It Ic pid-file Qq Pa /var/run/devd.pid ;
Specifies PID file.
.It Ic set Ar regexp-name Qq Ar (some|regexp) ;
Creates a regular expression and assigns it to the variable
.Ar regexp-name .
The variable is available throughout the rest of
the configuration file.
If the string begins with
.Ql \&! ,
it matches if the regular expression formed by the rest of the string
does not match.
All regular expressions have an implicit
.Ql ^$
around them.
.El
.Pp
The following sub-statements are supported within the
.Ic attach
and
.Ic detach
statements.
.Bl -tag -width ".Ic directory"
.It Ic action Qq Ar command ;
Command to execute upon a successful match.
Example
.Dq Li "/etc/pccard_ether $device-name start" .
.It Ic class Qq Ar string ;
This is shorthand for
.Dq Ic match Qo Li class Qc Qq Ar string .
.It Ic device-name Qq string ;
This is shorthand for
.Dq Ic match Qo Li device-name Qc Qq Ar string .
This matches a device named
.Ar string ,
which is allowed to be a regular expression or a variable previously created
containing a regular expression.
The
.Dq Li device-name
variable
is available for later use with the
.Ic action
statement.
.It Ic match Qo Ar variable Qc Qq Ar value ;
Matches the content of
.Ar value
against
.Ar variable ;
the content of
.Ar value
may be a regular expression.
Not required during
.Ic attach
nor
.Ic detach
events since the
.Ic device-name
statement takes care of all device matching.
For a partial list of variables, see below.
.It Ic media-type Qq Ar string ;
For network devices,
.Ic media-type
will match devices that have the given media type.
Valid media types are:
.Dq Li Ethernet ,
.Dq Li Tokenring ,
.Dq Li FDDI ,
.Dq Li 802.11 ,
and
.Dq Li ATM .
.It Ic subdevice Qq Ar string ;
This is shorthand for
.Dq Ic match Qo Li subdevice Qc Qq Ar string .
.El
.Pp
The following sub-statements are supported within the
.Ic nomatch
statement.
.Bl -tag -width ".Ic directory"
.It Ic action Qq Ar command ;
Same as above.
.It Ic match Qo Ar variable Qc Qq Ar value ;
Matches the content of
.Ar value
against
.Ar variable ;
the content of
.Ar value
may be a regular expression.
For a partial list of variables, see below.
.El
.Pp
The following sub-statements are supported within the
.Ic notify
statement.
The
.Dq Li notify
variable is available inside this statement and contains, a value, depending
on which system and subsystem that delivered the event.
.Bl -tag -width ".Ic directory"
.It Ic action Qq Ar command ;
Command to execute upon a successful match.
Example
.Dq Li "/etc/rc.d/power_profile $notify" .
.It Ic match Qo Ar system | subsystem | type | notify Qc Qq Ar value ;
Any number of
.Ic match
statements can exist within a
.Ic notify
statement;
.Ar value
can be either a fixed string or a regular expression.
Below is a list of available systems, subsystems, and types.
.It Ic media-type Qq Ar string ;
See above.
.El
.Ss Variables that can be used with the match statement
A partial list of variables and their possible values that can be used together
with the
.Ic match
statement.
The variables are published by the bus based on characteristics of the device
that generated the event (for device events).
Variables for other classes of events are dependent on those events.
.Pp
.Bl -tag -width ".Li manufacturer" -compact
.It Ic Variable
.Ic Description
.It Li *
The entire message from the current event
.It Li _
The entire message from the current event, after the initial type character
.It Li timestamp
The time this event was processed, in seconds since 1970 dot fraction
.It Li bus
Device name of parent bus.
.It Li cdev
Device node path if one is created by the
.Xr devfs 5
filesystem.
.It Li cisproduct
CIS-product.
.It Li cisvendor
CIS-vendor.
.It Li class
Device class.
.It Li device
Device ID.
.It Li devclass
Device Class (USB)
.It Li devsubclass
Device Sub-class (USB)
.It Li device-name
Name of attached/detached device.
.It Li endpoints
Endpoint count (USB)
.It Li function
Card functions.
.It Li interface
Interface ID (USB)
.It Li intclass
Interface Class (USB)
.It Li intprotocol
Interface Protocol  (USB)
.It Li intsubclass
Interface Sub-class (USB)
.It Li jail
Jail name for the process triggering the rule (RCTL)
.It Li manufacturer
Manufacturer ID (pccard).
.It Li mode
Peripheral mode (USB)
.It Li notify
Match the value of the
.Dq Li notify
variable.
.It Li parent
Parent device
.It Li pid
PID of the process triggering the rule (RCTL)
.It Li port
Hub port number (USB)
.It Li product
Product ID (pccard/USB).
.It Li release
Hardware revision (USB)
.It Li ruid
Real UID of the process triggering the rule (RCTL)
.It Li rule
Rule (RCTL)
.It Li sernum
Serial Number (USB).
.It Li slot
Card slot.
.It Li subvendor
Sub-vendor ID.
.It Li subdevice
Sub-device ID.
.It Li subsystem
Matches a subsystem of a system, see below.
.It Li system
Matches a system type, see below.
.It Li type
Type of notification, see below.
.It Li vendor
Vendor ID.
.El
.Ss Notify matching
A partial list of systems, subsystems, and types used within the
.Ic notify
mechanism.
.Pp
.Bl -tag -width ".Li coretemp" -compact
.It Sy System
.It Li ACPI
Events related to the ACPI subsystem.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li ACAD
AC line state ($notify=0x00 is offline, 0x01 is online).
.It Li Button
Button state ($notify=0x00 is power, 0x01 is sleep).
.It Li CMBAT
Battery events.
.It Li Lid
Lid state ($notify=0x00 is closed, 0x01 is open).
.It Li PROCESSOR
Processor state/configuration ($notify=0x81 is a change in available Cx states).
.It Li Resume
Resume notification.
.It Li Suspend
Suspend notification.
.It Li Thermal
Thermal zone events.
.El
.Pp
.It Li CARP
Events related to the
.Xr carp 4
protocol.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Ar vhid@interface
The
.Dq subsystem
contains the actual CARP vhid and the name of the network interface
on which the event took place.
.Bl -tag -width ".Li MASTER" -compact
.It Sy Type
.It Li MASTER
Node become the master for a virtual host.
.It Li BACKUP
Node become the backup for a virtual host.
.El
.El
.Pp
.It Li IFNET
Events related to the network subsystem.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Ar interface
The
.Dq subsystem
is the actual name of the network interface on which the event
took place.
.Bl -tag -width ".Li LINK_DOWN" -compact
.It Sy Type
.It Li LINK_UP
Carrier status changed to UP.
.It Li LINK_DOWN
Carrier status changed to DOWN.
.It Li ATTACH
The network interface is attached to the system.
.It Li DETACH
The network interface is detached from the system.
.El
.El
.Pp
.It Li DEVFS
Events related to the
.Xr devfs 5
filesystem.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li CDEV
.Bl -tag -width ".Li DESTROY" -compact
.It Sy Type
.It Li CREATE
The
.Xr devfs 5
node is created.
.It Li DESTROY
The
.Xr devfs 5
node is destroyed.
.El
.El
.Pp
.It Li GEOM
Events related to the
.Xr geom 4
framework.
The difference compared to
.Li DEVFS
is that
.Li GEOM
only includes disk-like devices.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li DEV
.Bl -tag -width ".Li MEDIACHANGE" -compact
.It Sy Type
.It Li CREATE
A
.Xr geom 4
device node is created.
.It Li DESTROY
A
.Xr geom 4
device node is destroyed.
.It Li GEOM::physpath
The physical path of a device has changed.
.It Li MEDIACHANGE
Physical media has changed.
.El
.El
.Pp
.It Li RCTL
Events related to the
.Xr rctl 8
framework.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li rule
.Bl -tag -width ".Li matched" -compact
.It Sy Type
.It Li matched
A rule with action specified as "devctl" was triggered.
.El
.El
.Pp
.It Li USB
Events related to the USB subsystem.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li DEVICE
.Bl -tag -width ".Li DETACH" -compact
.It Sy Type
.It Li ATTACH
USB device is attached to the system.
.It Li DETACH
USB device is detached from the system.
.El
.It Li INTERFACE
.Bl -tag -width ".Li DETACH" -compact
.It Sy Type
.It Li ATTACH
USB interface is attached to a device.
.It Li DETACH
USB interface is detached from a device.
.El
.El
.Pp
.It Li coretemp
Events related to the
.Xr coretemp 4
device.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li Thermal
Notification that the CPU core has reached critical temperature.
.Bl -tag -width ".Ar temperature" -compact
.It Sy Type
.It Ar temperature
String containing the temperature of the core that has become too hot.
.El
.El
.Pp
.It Li kern
Events related to the kernel.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li power
Information about the state of the system.
.Bl -tag -width ".li resume" -compact
.It Sy Type
.It Li resume
Notification that the system has woken from the suspended state.
.El
.El
.Pp
.It Li CAM
Events related to the
.Xr cam 4
system.
.Bl -tag -width ".Sy Subsystem" -compact
.It Sy Subsystem
.It Li periph
Events related to peripheral devices.
.Bl -tag -width ".li timeout" -compact
.It Sy Type
.It Li error
Generic errors.
.It Li timeout
Command timeouts.
.El
.El
.El
.Pp
A link state change to UP on the interface
.Dq Li fxp0
would result in the following notify event:
.Bd -literal -offset indent
system=IFNET, subsystem=fxp0, type=LINK_UP
.Ed
.Pp
An AC line state change to
.Dq offline
would result in the following event:
.Bd -literal -offset indent
system=ACPI, subsystem=ACAD, notify=0x00
.Ed
.Ss Comments
Comments may appear anywhere that whitespace may appear in a
configuration file.
To appeal to programmers of all kinds, they can
be written in C, C++, or shell/Perl constructs.
.Pp
C-style comments start with the two characters
.Ql /*
(slash, star) and end with
.Ql */
(star, slash).
Because they are completely delimited with these characters,
they can be used to comment only a portion of a line or to span
multiple lines.
.Pp
C-style comments cannot be nested.
For example, the following is
not valid because the entire comment ends with the first
.Ql */ :
.Bd -literal -offset indent
/* This is the start of a comment.
   This is still part of the comment.
/* This is an incorrect attempt at nesting a comment. */
   This is no longer in any comment. */
.Ed
.Pp
C++-style comments start with the two characters
.Ql //
(slash, slash) and continue to the end of the physical line.
They cannot be continued across multiple physical lines; to have
one logical comment span multiple lines, each line must use the
.Ql //
pair.
For example:
.Bd -literal -offset indent
// This is the start of a comment.  The next line
// is a new comment, even though it is logically
// part of the previous comment.
.Ed
.Sh FILES
.Bl -tag -width ".Pa /etc/devd.conf" -compact
.It Pa /etc/devd.conf
The
.Xr devd 8
configuration file.
.El
.Sh EXAMPLES
.Bd -literal
#
# This will catch link down events on the interfaces fxp0 and ath0
#
notify 0 {
	match "system"			"IFNET";
	match "subsystem"		"(fxp0|ath0)";
	match "type"			"LINK_DOWN";
	action "logger $subsystem is DOWN";
};

#
# Match lid open/close events
# These can be combined to a single event, by passing the
# value of $notify to the external script.
#
notify 0 {
	match "system"			"ACPI";
	match "subsystem"		"Lid";
	match "notify"			"0x00";
	action "logger Lid closed, we can sleep now!";
};

notify 0 {
	match "system"			"ACPI";
	match "subsystem"		"Lid";
	match "notify"			"0x01";
	action "logger Lid opened, the sleeper must awaken!";
};

#
# Match a USB device type
#
notify 0 {
	match "system"			"USB";
	match "subsystem"		"INTERFACE";
	match "type"			"ATTACH";
	match "intclass"		"0x0e";
	action "logger USB video device attached";
};

#
# Try to configure ath and wi devices with pccard_ether
# as they are attached.
#
attach 0 {
        device-name "(ath|wi)[0-9]+";
        action "/etc/pccard_ether $device-name start";
};

#
# Stop ath and wi devices as they are detached from
# the system.
#
detach 0 {
        device-name "(ath|wi)[0-9]+";
        action "/etc/pccard_ether $device-name stop";
};
.Ed
.Pp
The installed
.Pa /etc/devd.conf
has many additional examples.
.Sh SEE ALSO
.Xr cam 4 ,
.Xr coretemp 4 ,
.Xr devfs 5 ,
.Xr re_format 7 ,
.Xr devd 8