variable.subr revision 245437 
1if [ ! "$_VARIABLE_SUBR" ]; then _VARIABLE_SUBR=1
2#
3# Copyright (c) 2012 Devin Teske
4# All Rights Reserved.
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 (INLUDING, 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# $FreeBSD: head/usr.sbin/bsdconfig/share/variable.subr 245437 2013-01-14 21:03:34Z dteske $
28#
29############################################################ INCLUDES
30
31BSDCFG_SHARE="/usr/share/bsdconfig"
32. $BSDCFG_SHARE/common.subr || exit 1
33f_dprintf "%s: loading includes..." variable.subr
34f_include $BSDCFG_SHARE/dialog.subr
35
36############################################################ GLOBALS
37
38VARIABLES=
39
40#
41# Default behavior is to call f_variable_set_defaults() when loaded.
42#
43: ${VARIABLE_SELF_INITIALIZE=1}
44
45#
46# File to write when f_dump_variables() is called.
47#
48: ${VARIABLE_DUMPFILE:=/etc/bsdconfig.vars}
49
50############################################################ FUNCTIONS
51
52# f_variable_new $handle $variable
53#
54# Register a new variable named $variable with the given reference-handle
55# $handle. The environment variable $handle is set to $variable allowing you to
56# use the f_getvar() function (from common.subr) with $handle to get the value
57# of environment variable $variable. For example:
58#
59# 	f_variable_new VAR_ABC abc
60#
61# allows the later indirection:
62#
63# 	f_getvar $VAR_ABC
64#
65# to return the value of environment variable `abc'. Variables registered in
66# this manner are recorded in the $VARIABLES environment variable for later
67# allowing dynamic enumeration of so-called `registered/advertised' variables.
68#
69f_variable_new()
70{
71	local handle="$1" variable="$2"
72	[ "$handle" ] || return $FAILURE
73	f_dprintf "variable.subr: New variable %s -> %s" "$handle" "$variable"
74	setvar $handle $variable
75	VARIABLES="$VARIABLES${VARIABLES:+ }$handle"
76}
77
78# f_variable_get_value $var [ $fmt [ $opts ... ] ]
79#
80# Unless nonInteractive is set, prompt the user with a given value (pre-filled
81# with the value of $var) and give them the chance to change the value.
82#
83# Unlike f_getvar() (from common.subr) which can return a variable to the
84# caller on standard output, this function has no [meaningful] output.
85#
86# Returns success unless $var is either NULL or missing.
87#
88f_variable_get_value()
89{
90	local var="$1" cp
91
92	[ "$var" ] || return $FAILURE
93
94	if ! { f_getvar $var cp && ! f_interactive; }; then
95		shift 1 # var
96		cp=$( f_dialog_input "$( printf "$@" )" "$cp" ) &&
97			setvar $var "$cp"
98	fi
99
100	return $SUCCESS
101}
102
103# f_variable_set_defaults
104#
105# Installs sensible defaults for registered/advertised variables.
106#
107f_variable_set_defaults()
108{
109	#
110	# Initialize various user-edittable values to their defaults
111	#
112	setvar $VAR_RELNAME "$UNAME_R"
113
114	f_dprintf "f_variable_set_defaults: Defaults initialized."
115}
116
117# f_dump_variables
118#
119# Dump a list of registered/advertised variables and their respective values to
120# $VARIABLE_DUMPFILE. Returns success unless the file couldn't be written. If
121# an error occurs, it is displayed using f_dialog_msgbox() (from dialog.subr).
122#
123f_dump_variables()
124{
125	local err sanitize_awk="{ gsub(/'/, \"'\\\\''\"); print }"
126	if ! err=$(
127		( for handle in $VARIABLES; do
128			f_getvar $handle var || continue
129			f_getvar $var value || continue
130			value=$( echo "$value" | awk "$sanitize_awk" )
131			printf "%s='%s'\n" "$var" "$value"
132		  done > "$VARIABLE_DUMPFILE" ) 2>&1
133	); then
134		f_dialog_msgbox "$err"
135		return $FAILURE
136	fi
137}
138
139# f_debugging
140#
141# Are we in debug mode? Returns success if extra DEBUG information has been
142# requested (by setting $debug to non-NULL), otherwise false.
143#
144f_debugging()
145{
146	local value
147	f_getvar $VAR_DEBUG value && [ "$value" ]
148}
149
150# f_interactive()
151#
152# Are we running interactively? Return error if $nonInteractive is set and non-
153# NULL, otherwise return success.
154#
155f_interactive()
156{
157	local value
158	! f_getvar $VAR_NONINTERACTIVE value || [ ! "$value" ]
159}
160
161############################################################ MAIN
162
163#
164# Variables that can be tweaked from config files
165#
166f_variable_new VAR_CONFIG_FILE		configFile
167f_variable_new VAR_DEBUG		debug
168f_variable_new VAR_DEBUG_FILE		debugFile
169f_variable_new VAR_NO_ERROR		noError
170f_variable_new VAR_NONINTERACTIVE	nonInteractive
171f_variable_new VAR_RELNAME		releaseName
172
173#
174# Self-initialize unless requested otherwise
175#
176f_dprintf "%s: VARIABLE_SELF_INITIALIZE=[%s]" \
177          variable.subr "$VARIABLE_SELF_INITIALIZE"
178case "$VARIABLE_SELF_INITIALIZE" in
179""|0|[Nn][Oo]|[Oo][Ff][Ff]|[Ff][Aa][Ll][Ss][Ee]) : do nothing ;;
180*) f_variable_set_defaults
181esac
182
183f_dprintf "%s: Successfully loaded." variable.subr
184
185fi # ! $_VARIABLE_SUBR
186