From 6d4ed94d98bbe812805ed6ab71df0badbb8b9101 Mon Sep 17 00:00:00 2001
From: Kyle Evans <kevans@FreeBSD.org>
Date: Tue, 20 Feb 2018 21:23:01 +0000
Subject: [PATCH] lualoader: Prepare for interception of "boot" CLI cmd

core.boot and core.autoboot may both take arguments; add a helper to cleanly
append an argstring to the given loader command.

Also provide a popFrontTable() that we'll use pop the command name off of an
argv table. We don't have the table library included, and including it is
non-trivial, so we'll implement this one function that we need in lua for
the time being.
---
 stand/lua/core.lua | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/stand/lua/core.lua b/stand/lua/core.lua
index 3c51cc3d5442..e9c96a86ccbd 100644
--- a/stand/lua/core.lua
+++ b/stand/lua/core.lua
@@ -30,6 +30,13 @@ 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;
@@ -182,14 +189,14 @@ function core.setDefaults()
 	core.setVerbose(false);
 end
 
-function core.autoboot()
+function core.autoboot(argstr)
 	config.loadelf();
-	loader.perform("autoboot");
+	loader.perform(compose_loader_cmd("autoboot", argstr));
 end
 
-function core.boot()
+function core.boot(argstr)
 	config.loadelf();
-	loader.perform("boot");
+	loader.perform(compose_loader_cmd("boot", argstr));
 end
 
 function core.isSingleUserBoot()
@@ -235,6 +242,29 @@ function core.shallowCopyTable(tbl)
 	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