xref: /freebsd-10.2-release/usr.sbin/bsdconfig/share/variable.subr

if [ ! "$_VARIABLE_SUBR" ]; then _VARIABLE_SUBR=1
#
# Copyright (c) 2012 Devin Teske
# 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 (INLUDING, 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: head/usr.sbin/bsdconfig/share/variable.subr 245052 2013-01-05 02:08:47Z dteske $
#
############################################################ INCLUDES

BSDCFG_SHARE="/usr/share/bsdconfig"
. $BSDCFG_SHARE/common.subr || exit 1
f_dprintf "%s: loading includes..." variable.subr
f_include $BSDCFG_SHARE/dialog.subr

############################################################ GLOBALS

VARIABLES=

#
# Default behavior is to call f_variable_set_defaults() when loaded.
#
: ${VARIABLE_SELF_INITIALIZE=1}

#
# File to write when f_dump_variables() is called.
#
: ${VARIABLE_DUMPFILE:=/etc/bsdconfig.vars}

############################################################ FUNCTIONS

# f_variable_new $handle $variable
#
# Register a new variable named $variable with the given reference-handle
# $handle. The environment variable $handle is set to $variable allowing you to
# use the f_getvar() function (from common.subr) with $handle to get the value
# of environment variable $variable. For example:
#
# 	f_variable_new VAR_ABC abc
#
# allows the later indirection:
#
# 	f_getvar $VAR_ABC
#
# to return the value of environment variable `abc'. Variables registered in
# this manner are recorded in the $VARIABLES environment variable for later
# allowing dynamic enumeration of so-called `registered/advertised' variables.
#
f_variable_new()
{
	local handle="$1" variable="$2"
	[ "$handle" ] || return $FAILURE
	f_dprintf "variable.subr: New variable %s -> %s" "$handle" "$variable"
	setvar $handle $variable
	VARIABLES="$VARIABLES${VARIABLES:+ }$handle"
}

# f_variable_get_value $var [ $fmt [ $opts ... ] ]
#
# Unless nonInteractive is set, prompt the user with a given value (pre-filled
# with the value of $var) and give them the chance to change the value.
#
# Unlike f_getvar() (from common.subr) which can return a variable to the
# caller on standard output, this function has no [meaningful] output.
#
# Returns success unless $var is either NULL or missing.
#
f_variable_get_value()
{
	local var="$1" cp

	[ "$var" ] || return $FAILURE

	if ! { f_getvar $var cp && ! f_interactive; }; then
		shift 1 # var
		cp=$( f_dialog_input "$( printf "$@" )" "$cp" ) &&
			setvar $var "$cp"
	fi

	return $SUCCESS
}

# f_variable_set_defaults
#
# Installs sensible defaults for registered/advertised variables.
#
f_variable_set_defaults()
{
	#
	# Initialize various user-edittable values to their defaults
	#
	setvar $VAR_RELNAME "$UNAME_R"

	f_dprintf "f_variable_set_defaults: Defaults initialized."
}

# f_dump_variables
#
# Dump a list of registered/advertised variables and their respective values to
# $VARIABLE_DUMPFILE. Returns success unless the file couldn't be written. If
# an error occurs, it is displayed using f_show_msg() (from common.subr).
#
f_dump_variables()
{
	local err sanitize_awk="{ gsub(/'/, \"'\\\\''\"); print }"
	if ! err=$(
		( for handle in $VARIABLES; do
			f_getvar $handle var || continue
			f_getvar $var value || continue
			value=$( echo "$value" | awk "$sanitize_awk" )
			printf "%s='%s'\n" "$var" "$value"
		  done > "$VARIABLE_DUMPFILE" ) 2>&1
	); then
		f_show_msg "%s" "$err"
		return $FAILURE
	fi
}

# f_debugging
#
# Are we in debug mode? Returns success if extra DEBUG information has been
# requested (by setting $debug to non-NULL), otherwise false.
#
f_debugging()
{
	local value
	f_getvar $VAR_DEBUG value && [ "$value" ]
}

# f_interactive()
#
# Are we running interactively? Return error if $nonInteractive is set and non-
# NULL, otherwise return success.
#
f_interactive()
{
	local value
	! f_getvar $VAR_NONINTERACTIVE value || [ ! "$value" ]
}

############################################################ MAIN

#
# Variables that can be tweaked from config files
#
f_variable_new VAR_CONFIG_FILE		configFile
f_variable_new VAR_DEBUG		debug
f_variable_new VAR_DEBUG_FILE		debugFile
f_variable_new VAR_NO_ERROR		noError
f_variable_new VAR_NONINTERACTIVE	nonInteractive
f_variable_new VAR_RELNAME		releaseName

#
# Self-initialize unless requested otherwise
#
f_dprintf "%s: VARIABLE_SELF_INITIALIZE=[%s]" \
          variable.subr "$VARIABLE_SELF_INITIALIZE"
case "$VARIABLE_SELF_INITIALIZE" in
""|0|[Nn][Oo]|[Oo][Ff][Ff]|[Ff][Aa][Ll][Ss][Ee]) : do nothing ;;
*) f_variable_set_defaults
esac

f_dprintf "%s: Successfully loaded." variable.subr

fi # ! $_VARIABLE_SUBR