1.\" 2.\" SPDX-License-Identifier: BSD-2-Clause 3.\" 4.\" Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org> 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.Dd June 9, 2018 28.Dt HOOK.LUA 8 29.Os 30.Sh NAME 31.Nm hook.lua 32.Nd FreeBSD hook module 33.Sh DESCRIPTION 34.Nm 35contains functionality for defining hook types and attaching hooks. 36Hooks are functions used to attach custom behaviors at pre-defined points in 37loader execution. 38These pre-defined points are what we refer to as 39.Dq hook types . 40.Pp 41Before using the functionality provided by 42.Nm , 43it must be included with a statement such as the following: 44.Pp 45.Dl local hook = require("hook") 46.Ss Exported functions 47The following functions are exported from 48.Nm : 49.Bl -tag -width hook.registerType -offset indent 50.It Fn hook.registerType hooktype 51Adds 52.Ev hooktype 53as a recognized hook type. 54This allows functions to be added to run when hooks of this type are invoked 55using 56.Fn hook.runAll hooktype . 57.It Fn hook.register hooktype hookfunc 58Register 59.Ev hookfunc 60to be run when hooks of type 61.Ev hooktype 62are invoked. 63.It Fn hook.runAll hooktype 64Invoke all hooks registered for type 65.Ev hooktype . 66Hooks are invoked in the order in which they are registered. 67.El 68.Ss Hook Naming Guidelines 69Hook names should consist of the name of the module they are defined in, as well 70as a verb describing when the hook is executed, separated by a period. 71For example, 72.Dq config.reloaded 73is defined in the 74.Xr config.lua 8 75module and run when the configuration is reloaded. 76.Sh EXAMPLES 77To register a hook to be run when configuration is reloaded: 78.Pp 79.Bd -literal -offset indent -compact 80local hook = require("hook") 81 82local function configuration_was_reloaded() 83 print("Configuration was reloaded!") 84end 85 86hook.register("config.reloaded", configuration_was_reloaded) 87.Ed 88.Sh AUTHORS 89The 90.Nm 91file was originally written by 92.An Kyle Evans Aq Mt kevans@FreeBSD.org . 93