xref: /freebsd/stand/lua/color.lua (revision 02e9120893770924227138ba49df1edb3896112a)
1--
2-- SPDX-License-Identifier: BSD-2-Clause
3--
4-- Copyright (c) 2015 Pedro Souza <pedrosouza@freebsd.org>
5-- All rights reserved.
6--
7-- Redistribution and use in source and binary forms, with or without
8-- modification, are permitted provided that the following conditions
9-- are met:
10-- 1. Redistributions of source code must retain the above copyright
11--    notice, this list of conditions and the following disclaimer.
12-- 2. Redistributions in binary form must reproduce the above copyright
13--    notice, this list of conditions and the following disclaimer in the
14--    documentation and/or other materials provided with the distribution.
15--
16-- THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17-- ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18-- IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19-- ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20-- FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21-- DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22-- OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23-- HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24-- LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25-- OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26-- SUCH DAMAGE.
27--
28
29local core = require("core")
30local hook = require("hook")
31
32local color = {}
33
34local function recalcDisabled()
35	color.disabled = not color.isEnabled()
36end
37
38-- Module exports
39color.BLACK   = 0
40color.RED     = 1
41color.GREEN   = 2
42color.YELLOW  = 3
43color.BLUE    = 4
44color.MAGENTA = 5
45color.CYAN    = 6
46color.WHITE   = 7
47
48color.DEFAULT = 9
49color.BRIGHT  = 1
50color.DIM     = 2
51
52function color.isEnabled()
53	local c = loader.getenv("loader_color")
54	if c ~= nil then
55		return c:lower() ~= "no" and c ~= "0"
56	end
57	return true
58end
59
60function color.escapefg(color_value)
61	if color.disabled then
62		return ''
63	end
64	return core.KEYSTR_CSI .. "3" .. color_value .. "m"
65end
66
67function color.resetfg()
68	if color.disabled then
69		return ''
70	end
71	return color.escapefg(color.DEFAULT)
72end
73
74function color.escapebg(color_value)
75	if color.disabled then
76		return ''
77	end
78	return core.KEYSTR_CSI .. "4" .. color_value .. "m"
79end
80
81function color.resetbg()
82	if color.disabled then
83		return ''
84	end
85	return color.escapebg(color.DEFAULT)
86end
87
88function color.escape(fg_color, bg_color, attribute)
89	if color.disabled then
90		return ""
91	end
92	if attribute == nil then
93		attribute = ""
94	else
95		attribute = attribute .. ";"
96	end
97	return core.KEYSTR_CSI .. attribute ..
98	    "3" .. fg_color .. ";4" .. bg_color .. "m"
99end
100
101function color.default()
102	if color.disabled then
103		return ""
104	end
105	return color.escape(color.DEFAULT, color.DEFAULT)
106end
107
108function color.highlight(str)
109	if color.disabled then
110		return str
111	end
112	-- We need to reset attributes as well as color scheme here, just in
113	-- case the terminal defaults don't match what we're expecting.
114	return core.KEYSTR_CSI .. "1m" .. str .. core.KEYSTR_CSI .. "22m"
115end
116
117recalcDisabled()
118hook.register("config.loaded", recalcDisabled)
119
120return color
121