1if [ ! "$_STRUCT_SUBR" ]; then _STRUCT_SUBR=1 2# 3# Copyright (c) 2012-2013 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 (INCLUDING, 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# $FreeBSD$ 28# 29############################################################ INCLUDES 30 31BSDCFG_SHARE="/usr/share/bsdconfig" 32. $BSDCFG_SHARE/common.subr || exit 1 33 34############################################################ FUNCTIONS 35 36# f_struct_define $type $member_name1 ... 37# 38# Define a new `structure' type $type made up of the properties $member_name1 39# $member_name2 and so-on. Properties are not typed and can hold any type of 40# data (including names of other structs). 41# 42# Before creating instances of a struct (using f_struct_new $type $name) you 43# should use this function to define $type. 44# 45# Both $type and member names should consist only of alpha-numeric letters or 46# the underscore. 47# 48f_struct_define() 49{ 50 local type="$1" 51 [ "$type" ] || return $FAILURE 52 shift 53 setvar "_struct_typedef_$type" "$*" 54} 55 56# f_struct_new $type $name 57# 58# Create a new `structure' named $name of type $type. There are two ways to 59# access properties of a struct, but they are not equal (each method has its 60# own unique benefits, discussed below). 61# 62# The primary method of accessing (both setting and getting) properties of any 63# struct is through the f_struct() function below. 64# 65# The secondary method of accessing data is by using $name as a function. 66# 67# Both access methods are cross-platform compatible with any version of sh(1). 68# Below is an example of the primary access method: 69# 70# f_struct_new MY_STRUCT_TYPE my_struct 71# f_struct my_struct set abc 123 72# f_struct my_struct get abc # prints 123 to stdout 73# f_struct my_struct get abc abc # sets local variable $abc to 123 74# 75# Alternatively, the secondary access method (details below): 76# 77# f_struct_new MY_STRUCT_TYPE my_struct 78# my_struct set abc 123 79# my_struct get abc # prints 123 to stdout 80# my_struct get abc abc # sets local variable $abc to 123 81# 82# The secondary form should only be used if/when: 83# + You are certain that the structure already exists 84# + You want a syntax error if/when the struct does not exist 85# 86# The primary benefit to the secondary form is syntax cleanliness and read- 87# ability. If you are unsure if a given struct exists (which would cause a 88# syntax error when using this form), you can use the primary access method to 89# first test for the existence of the struct. For example: 90# 91# if f_struct my_struct; then 92# my_struct get abc # only executed if my_struct exists 93# fi 94# 95# For more information, see the f_struct() function. 96# 97f_struct_new() 98{ 99 local type="$1" name="$2" 100 f_dprintf "f_struct_new: type=[%s] name=[%s]" "$type" "$name" 101 [ "$name" ] || return $FAILURE 102 setvar "_struct_type_$name" "$type" || return $FAILURE 103 # OK to use bare $name at this point 104 eval $name\(\){ f_struct $name \"\$@\"\; } 105} 106 107# f_struct $name 108# f_struct $name get $property [$var_to_set] 109# f_struct $name set $property $new_value 110# f_struct $name unset $property 111# 112# Access routine for getting, setting, unsetting, and testing properties of 113# `structures'. 114# 115# If only given $name, returns success if struct $name has been created (using 116# the f_struct_new() function above). 117# 118# For getting properties of a struct (versus setting) there are two methods of 119# access. If $var_to_set is missing or NULL, the value of the property is 120# printed to standard output for capturing in a sub-shell (which is less- 121# recommended because of performance degredation; for example, when called in a 122# loop). Returns success unless the property is unset. 123# 124# For setting properties of a struct, sets the value of $property to $new_value 125# and returns success. 126# 127# For unsetting, the underlying environment variable associated with the given 128# $property is unset. 129# 130f_struct() 131{ 132 local __name="$1" __action="$2" __property="$3" 133 case $# in 134 0) return $FAILURE ;; 135 1) f_have $__name ;; 136 *) case "$__action" in 137 get) local __var_to_set="$4" 138 f_getvar "_struct_value_${__name}_$__property" "$__var_to_set" 139 ;; 140 set) local new_value="$4" 141 setvar "_struct_value_${__name}_$__property" "$new_value" ;; 142 unset) unset "_struct_value_${__name}_$__property" ;; 143 esac 144 esac 145 # Return the status of the last command above 146} 147 148# f_struct_free $name 149# 150# Unset the collection of environment variables and accessor-function 151# associated with struct $name. 152# 153f_struct_free() 154{ 155 local name="$1" type member members 156 f_getvar "_struct_type_$name" type 157 f_dprintf "f_struct_free: name=[%s] type=[%s]" "$name" "$type" 158 [ "$name" ] || return $FAILURE 159 f_getvar "_struct_typedef_$type" members 160 for member in $members; do 161 f_struct "$name" unset $member 162 done 163 unset -f "$name" 164 unset "_struct_type_$name" 165} 166 167# f_struct_copy $from_name $to_name 168# 169# Copy the properties of one struct to another. If struct $to_name does not 170# exist, it is created. If struct $from_name does not exist, nothing is done 171# and struct $to_name remains unmodified. 172# 173# Returns success unless struct $to_name did not exist and f_struct_new() was 174# unable to create it. 175# 176f_struct_copy() 177{ 178 local from_name="$1" to_name="$2" type 179 f_dprintf "f_struct_copy: from_name=[%s] to_name=[%s]" \ 180 "$from_name" "$to_name" 181 f_getvar "_struct_type_$from_name" type 182 f_struct "$to_name" || 183 f_struct_new "$type" "$to_name" || return $FAILURE 184 f_struct "$from_name" || return $SUCCESS 185 f_dprintf "f_struct_copy: copying properties from %s to %s" \ 186 "$from_name" "$to_name" 187 local property properties from_value n=0 k=0 188 f_getvar "_struct_typedef_$type" properties 189 for property in $properties; do 190 k=$(( $k + 1 )) 191 if f_struct "$from_name" get $property from_value; then 192 f_struct "$to_name" set $property "$from_value" 193 n=$(( $n + 1 )) 194 else 195 f_struct "$to_name" unset $property 196 fi 197 done 198 f_dprintf "f_struct_copy: copied %u of %u properties from %s to %s" \ 199 "$n" "$k" "$from_name" "$to_name" 200} 201 202############################################################ MAIN 203 204f_dprintf "%s: Successfully loaded." struct.subr 205 206fi # ! $_STRUCT_SUBR 207