Index: head/stand/lua/core.lua
===================================================================
--- head/stand/lua/core.lua	(revision 329851)
+++ head/stand/lua/core.lua	(revision 329852)
@@ -1,330 +1,331 @@
 --
 -- SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 --
 -- Copyright (c) 2015 Pedro Souza <pedrosouza@freebsd.org>
+-- Copyright (c) 2018 Kyle Evans <kevans@FreeBSD.org>
 -- 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. Redistributions in binary form must reproduce the above copyright
 --    notice, this list of conditions and the following disclaimer in the
 --    documentation and/or other materials provided with the distribution.
 --
 -- 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.
 --
 -- $FreeBSD$
 --
 
 local config = require("config")
 
 local core = {}
 
 local compose_loader_cmd = function(cmd_name, argstr)
 	if argstr ~= nil then
 		cmd_name = cmd_name .. " " .. argstr
 	end
 	return cmd_name
 end
 
 -- Module exports
 -- Commonly appearing constants
 core.KEY_BACKSPACE	= 8
 core.KEY_ENTER		= 13
 core.KEY_DELETE		= 127
 
 core.KEYSTR_ESCAPE	= "\027"
 
 core.MENU_RETURN	= "return"
 core.MENU_ENTRY		= "entry"
 core.MENU_SEPARATOR	= "separator"
 core.MENU_SUBMENU	= "submenu"
 core.MENU_CAROUSEL_ENTRY	= "carousel_entry"
 
 function core.setVerbose(b)
 	if b == nil then
 		b = not core.verbose
 	end
 
 	if b then
 		loader.setenv("boot_verbose", "YES")
 	else
 		loader.unsetenv("boot_verbose")
 	end
 	core.verbose = b
 end
 
 function core.setSingleUser(b)
 	if b == nil then
 		b = not core.su
 	end
 
 	if b then
 		loader.setenv("boot_single", "YES")
 	else
 		loader.unsetenv("boot_single")
 	end
 	core.su = b
 end
 
 function core.getACPIPresent(checkingSystemDefaults)
 	local c = loader.getenv("hint.acpi.0.rsdp")
 
 	if c ~= nil then
 		if checkingSystemDefaults then
 			return true
 		end
 		-- Otherwise, respect disabled if it's set
 		c = loader.getenv("hint.acpi.0.disabled")
 		return c == nil or tonumber(c) ~= 1
 	end
 	return false
 end
 
 function core.setACPI(b)
 	if b == nil then
 		b = not core.acpi
 	end
 
 	if b then
 		loader.setenv("acpi_load", "YES")
 		loader.setenv("hint.acpi.0.disabled", "0")
 		loader.unsetenv("loader.acpi_disabled_by_user")
 	else
 		loader.unsetenv("acpi_load")
 		loader.setenv("hint.acpi.0.disabled", "1")
 		loader.setenv("loader.acpi_disabled_by_user", "1")
 	end
 	core.acpi = b
 end
 
 function core.setSafeMode(b)
 	if b == nil then
 		b = not core.sm
 	end
 	if b then
 		loader.setenv("kern.smp.disabled", "1")
 		loader.setenv("hw.ata.ata_dma", "0")
 		loader.setenv("hw.ata.atapi_dma", "0")
 		loader.setenv("hw.ata.wc", "0")
 		loader.setenv("hw.eisa_slots", "0")
 		loader.setenv("kern.eventtimer.periodic", "1")
 		loader.setenv("kern.geom.part.check_integrity", "0")
 	else
 		loader.unsetenv("kern.smp.disabled")
 		loader.unsetenv("hw.ata.ata_dma")
 		loader.unsetenv("hw.ata.atapi_dma")
 		loader.unsetenv("hw.ata.wc")
 		loader.unsetenv("hw.eisa_slots")
 		loader.unsetenv("kern.eventtimer.periodic")
 		loader.unsetenv("kern.geom.part.check_integrity")
 	end
 	core.sm = b
 end
 
 function core.kernelList()
 	local k = loader.getenv("kernel")
 	local v = loader.getenv("kernels")
 	local autodetect = loader.getenv("kernels_autodetect") or ""
 
 	local kernels = {}
 	local unique = {}
 	local i = 0
 	if k ~= nil then
 		i = i + 1
 		kernels[i] = k
 		unique[k] = true
 	end
 
 	if v ~= nil then
 		for n in v:gmatch("([^; ]+)[; ]?") do
 			if unique[n] == nil then
 				i = i + 1
 				kernels[i] = n
 				unique[n] = true
 			end
 		end
 	end
 
 	-- Base whether we autodetect kernels or not on a loader.conf(5)
 	-- setting, kernels_autodetect. If it's set to 'yes', we'll add
 	-- any kernels we detect based on the criteria described.
 	if autodetect:lower() ~= "yes" then
 		return kernels
 	end
 
 	-- Automatically detect other bootable kernel directories using a
 	-- heuristic.  Any directory in /boot that contains an ordinary file
 	-- named "kernel" is considered eligible.
 	for file in lfs.dir("/boot") do
 		local fname = "/boot/" .. file
 
 		if file == "." or file == ".." then
 			goto continue
 		end
 
 		if lfs.attributes(fname, "mode") ~= "directory" then
 			goto continue
 		end
 
 		if lfs.attributes(fname .. "/kernel", "mode") ~= "file" then
 			goto continue
 		end
 
 		if unique[file] == nil then
 			i = i + 1
 			kernels[i] = file
 			unique[file] = true
 		end
 
 		::continue::
 	end
 	return kernels
 end
 
 function core.bootenvDefault()
 	return loader.getenv("zfs_be_active")
 end
 
 function core.bootenvList()
 	local bootenv_count = tonumber(loader.getenv("bootenvs_count"))
 	local bootenvs = {}
 	local curenv
 	local envcount = 0
 	local unique = {}
 
 	if bootenv_count == nil or bootenv_count <= 0 then
 		return bootenvs
 	end
 
 	-- Currently selected bootenv is always first/default
 	curenv = core.bootenvDefault()
 	if curenv ~= nil then
 		envcount = envcount + 1
 		bootenvs[envcount] = curenv
 		unique[curenv] = true
 	end
 
 	for curenv_idx = 0, bootenv_count - 1 do
 		curenv = loader.getenv("bootenvs[" .. curenv_idx .. "]")
 		if curenv ~= nil and unique[curenv] == nil then
 			envcount = envcount + 1
 			bootenvs[envcount] = curenv
 			unique[curenv] = true
 		end
 	end
 	return bootenvs
 end
 
 function core.setDefaults()
 	core.setACPI(core.getACPIPresent(true))
 	core.setSafeMode(false)
 	core.setSingleUser(false)
 	core.setVerbose(false)
 end
 
 function core.autoboot(argstr)
 	config.loadelf()
 	loader.perform(compose_loader_cmd("autoboot", argstr))
 end
 
 function core.boot(argstr)
 	config.loadelf()
 	loader.perform(compose_loader_cmd("boot", argstr))
 end
 
 function core.isSingleUserBoot()
 	local single_user = loader.getenv("boot_single")
 	return single_user ~= nil and single_user:lower() == "yes"
 end
 
 function core.isZFSBoot()
 	local c = loader.getenv("currdev")
 
 	if c ~= nil then
 		return c:match("^zfs:") ~= nil
 	end
 	return false
 end
 
 function core.isSerialBoot()
 	local c = loader.getenv("console")
 
 	if c ~= nil then
 		if c:find("comconsole") ~= nil then
 			return true
 		end
 	end
 
 	local s = loader.getenv("boot_serial")
 	if s ~= nil then
 		return true
 	end
 
 	local m = loader.getenv("boot_multicons")
 	if m ~= nil then
 		return true
 	end
 	return false
 end
 
 function core.isSystem386()
 	return loader.machine_arch == "i386"
 end
 
 -- This may be a better candidate for a 'utility' module.
 function core.shallowCopyTable(tbl)
 	local new_tbl = {}
 	for k, v in pairs(tbl) do
 		if type(v) == "table" then
 			new_tbl[k] = core.shallowCopyTable(v)
 		else
 			new_tbl[k] = v
 		end
 	end
 	return new_tbl
 end
 
 -- XXX This should go away if we get the table lib into shape for importing.
 -- As of now, it requires some 'os' functions, so we'll implement this in lua
 -- for our uses
 function core.popFrontTable(tbl)
 	-- Shouldn't reasonably happen
 	if #tbl == 0 then
 		return nil, nil
 	elseif #tbl == 1 then
 		return tbl[1], {}
 	end
 
 	local first_value = tbl[1]
 	local new_tbl = {}
 	-- This is not a cheap operation
 	for k, v in ipairs(tbl) do
 		if k > 1 then
 			new_tbl[k - 1] = v
 		end
 	end
 
 	return first_value, new_tbl
 end
 
 -- On i386, hint.acpi.0.rsdp will be set before we're loaded. On !i386, it will
 -- generally be set upon execution of the kernel. Because of this, we can't (or
 -- don't really want to) detect/disable ACPI on !i386 reliably. Just set it
 -- enabled if we detect it and leave well enough alone if we don't.
 if core.isSystem386() and core.getACPIPresent(false) then
 	core.setACPI(true)
 end
 return core