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 4, 2026 28.Dt CORE.LUA 8 29.Os 30.Sh NAME 31.Nm core.lua 32.Nd bootloader core module 33.Sh DESCRIPTION 34.Nm 35contains core functionality that does not have a more fitting module. 36.Pp 37Before hooking into or using the functionality provided by 38.Nm , 39it must be included with a statement such as the following: 40.Pp 41.Dl local core = require("core") 42.Ss CONSTANTS 43The following raw key code constants are defined in 44.Nm : 45.Bl -tag -width KEY_BACKSPACE -compact -offset indent 46.It Ic KEY_BACKSPACE 47The backspace code. 48Should generally be checked along with 49.Ic KEY_DELETE 50for backspace functionality. 51.It Ic KEY_ENTER 52The enter key, or hard return. 53.It Ic KEY_DELETE 54The delete code. 55Should generally be checked along with 56.Ic KEY_BACKSPACE 57for backspace functionality. 58.El 59.Pp 60The following key-string constants are defined in 61.Nm : 62.Bl -tag -width KEYSTR_ESCAPE -compact -offset indent 63.It Ic KEYSTR_ESCAPE 64The escape key. 65.It Ic KEYSTR_CSI 66The ANSI CSI sequence. 67.El 68.Pp 69The following menu entry type constants are defined in 70.Nm : 71.Bl -tag -width MENU_CAROUSEL_ENTRY -compact -offset indent 72.It Ic MENU_RETURN 73Return to the parent menu. 74.It Ic MENU_ENTRY 75A normal menu entry. 76.It Ic MENU_SEPARATOR 77A menu entry that serves as a separator. 78.It Ic MENU_SUBMENU 79A menu entry that opens a submenu when selected. 80.It Ic MENU_CAROUSEL_ENTRY 81A menu entry that rotates through items like a carousel upon selection of the 82menu entry. 83.El 84.Pp 85Please see 86.Xr menu.lua 8 87for extended descriptions and usage of the 88.Ic MENU_* 89constants. 90.Ss Exported functions 91The following functions are exported from 92.Nm : 93.Bl -tag -width core.setSingleUser -offset indent 94.It Fn core.setVerbose verbose 95Sets or unsets 96.Ev boot_verbose . 97If 98.Fa verbose 99is omitted, toggle the current verbose setting. 100.It Fn core.setSingleUser singleUser 101Sets or unsets 102.Ev boot_single . 103If 104.Fa singleUser 105is omitted, toggle the current single user setting. 106.It Fn core.getACPI 107Return true if ACPI is both present and not explicitly disabled by 108.Ev hints.acpi.0.disabled . 109.It Fn core.hasACPI 110Checks whether ACPI support is present. 111This requires the loader to probe the system and set 112.Ev acpi.rsdp 113early before starting the interpreter. 114.It Fn core.setACPI acpi 115Sets or unsets 116.Ev acpi_load , 117.Ev hint.acpi.0.disabled , 118and 119.Ev loader.acpi_disabled_by_user . 120If 121.Fa acpi 122is omitted, toggle the current ACPI setting. 123.It Fn core.setSafeMode safeMode 124Set the safe mode setting. 125Sets or unsets 126.Ev kern.smp.disabled , 127.Ev hw.ata.ata_dma , 128.Ev hw.ata.atapi_dma , 129.Ev kern.eventtimer.periodic , 130and 131.Ev kern.geom.part.check_integrity . 132If 133.Fa safeMode 134is omitted, toggle the current safe mode setting. 135.It Fn core.clearCachedKernels 136Clears out the cache of kernels to be displayed on the boot menu. 137This function is registered as a 138.Ev config.reloaded 139hook. 140It is used to invalidate the kernel list whenever it may have changed, either 141due to a boot environment change or a potential change in either 142.Ic kernel 143or 144.Ic kernels . 145.It Fn core.hasFeature featureName 146Checks whether the named 147.Fa featureName 148is enabled in the current loader. 149This is specifically used for detecting capabilities of the loaded loader 150binary, so that one can reasonably implement backwards compatibility shims if 151needed. 152.It Fn core.kernelList 153Returns a table of kernels to display on the boot menu. 154This will combine 155.Ic kernel 156and 157.Ic kernels 158from 159.Xr loader.conf 5 . 160If 161.Ic kernels_autodetect 162is set in 163.Xr loader.conf 5 , 164kernels will be autodetected from the current system. 165.It Fn core.bootenvDefault 166Returns the default boot environment, nil if unset. 167.It Fn core.bootenvFilter func 168Installs a filter 169.Fa func 170into 171.Fn core.bootenvList . 172If the 173.Fa func 174returns true, then the boot environment is retained in the list. 175Otherwise, the boot environment is hidden. 176The old filter, if any, is returned to allow the caller to compose a filter on 177top of another filter. 178.It Fn core.bootenvIter 179Returns an iterator over the known boot environment list. 180The returned boot environment names do not include the boot environmnt root, 181which would need to be added back on from the 182.Ev zfs_be_root 183environment variable. 184.It Fn core.bootenvList 185Returns a table of boot environments, or an empty table. 186These will be picked up using the 187.Ev bootenvs 188and 189.Ev bootenvs_count 190variables set by 191.Xr loader 8 . 192.It Fn core.setDefaults 193Resets ACPI, safe mode, single user, and verbose settings to their system 194defauilts. 195.It Fn core.autoboot argstr 196Loads the kernel and specified modules, then invokes the 197.Ic autoboot 198.Xr loader 8 199command with 200.Fa argstr 201as-is. 202.It Fn core.boot argstr 203Loads the kernel and specified modules, then invokes the 204.Ic boot 205.Xr loader 8 206command with 207.Fa argstr 208as-is. 209.It Fn core.isSingleUserBoot 210Returns true if 211.Ev boot_single 212is set to yes. 213.It Fn core.isZFSBoot 214Returns true if 215.Ev currdev 216is set to a 217.Xr zfs 8 218dataset. 219.It Fn core.isSerialBoot 220Returns true if we are booting over serial. 221This checks 222.Ev console , 223.Ev boot_serial , 224and 225.Ev boot_multicons . 226.It Fn core.deepCopyTable tbl 227Recursively deep copies 228.Fa tbl 229and returns the result. 230.It Fn core.popFrontTable tbl 231Pops the front element off of 232.Fa tbl , 233and returns two return values: the front element, and the rest of the table. 234If there are no elements, this returns nil and nil. 235If there is one element, this returns the front element and an empty table. 236This will not operate on truly associative tables; numeric indices are 237required. 238.It Fn core.switchBE beName 239Switch to the requested 240.Fa beName . 241It may be either be formatted as a fully-qualified loader dataset path 242.Dq zfs:pool/ROOT/beName , 243or like one of 244.Dq pool/ROOT/beName 245or 246.Dq beName . 247.It Fn core.loaderTooOld 248Returns true if the loader is too old. 249Specifically, this means, is the loader old enough to require one or more 250workarounds in the current lua base modules. 251.El 252.Sh SEE ALSO 253.Xr loader.conf 5 , 254.Xr loader 8 , 255.Xr menu.lua 8 256.Sh AUTHORS 257The 258.Nm 259file was originally written by 260.An Pedro Souza Aq Mt pedrosouza@FreeBSD.org . 261Later work and this manual page was done by 262.An Kyle Evans Aq Mt kevans@FreeBSD.org . 263