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