freebsd-src/libexec/rc/safe_eval.sh
Simon J. Gerraty 35399f68c8 safe_dot check file is a file
Since we are being paranoid, check that each arg to safe_dot is
actually a file as well as non-empty.

Check for white-space in filenames - these require special handling.
2024-08-16 13:15:20 -07:00

96 lines
1.9 KiB
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# SPDX-License-Identifier: BSD-2-Clause
# RCSid:
# $Id: safe_eval.sh,v 1.20 2024/08/16 00:57:58 sjg Exp $
#
# @(#) Copyright (c) 2023-2024 Simon J. Gerraty
#
# This file is provided in the hope that it will
# be of use. There is absolutely NO WARRANTY.
# Permission to copy, redistribute or otherwise
# use this file is hereby granted provided that
# the above copyright notice and this notice are
# left intact.
#
# Please send copies of changes and bug-fixes to:
# sjg@crufty.net
_SAFE_EVAL_SH=:
##
# safe_set
#
# return a safe variable setting
# any non-alphanumeric chars are replaced with '_'
#
safe_set() {
${SED:-sed} 's/[ ]*#.*//;/^[A-Za-z_][A-Za-z0-9_]*=/!d;s;[^A-Za-z0-9_. "$,/=-];_;g'
}
##
# safe_eval [file]
#
# eval variable assignments only from file
# taking care to eliminate any shell meta chars
#
safe_eval() {
eval `cat "$@" | safe_set`
}
##
# safe_eval_export [file]
#
# eval variable assignments only from file
# taking care to eliminate any shell meta chars
# export any variables thus set
#
safe_eval_export() {
eval `cat "$@" | safe_set | ${SED:-sed} 's/^\([^=]*\)=.*/&; export \1/'`
}
##
# safe_dot file [...]
#
# feed all "file" that exist to safe_eval
#
safe_dot() {
eval ${local:-:} ef ex f rc
ef=
ex=
rc=1
while :
do
case "$1" in
--export) ex=_export; shift;;
*) break;;
esac
done
for f in "$@"
do
test -s "$f" -a -f "$f" || continue
: check for space or tab in "$f"
case "$f" in
*[[:space:]]*|*" "*|*" "*) # we cannot do this efficiently
dotted="$dotted $f"
safe_eval$ex "$f"
rc=$?
continue
;;
esac
ef="${ef:+$ef }$f"
dotted="$dotted $f"
done
test -z "$ef" && return $rc
safe_eval$ex $ef
return 0
}
case /$0 in
*/safe_eval*)
case "$1" in
dot|eval|set) op=safe_$1; shift; $op "$@";;
*) safe_dot "$@";;
esac
;;
esac