=~ operator is not supported by busybox

[zhangyoufu]

tested on alpine:latest

PS: I don't like the idea of copy & paste from some ksh script

[zhangyoufu]

--- a/syslog-redirect.in
+++ b/syslog-redirect.in
@@ -20,25 +20,6 @@ esac
 
 pdie() { echo "$0: ERROR: ${1-}" 1>&2; exit "${2-1}"; }
 
-getopts_want_arg()
-{
-  if [[ $# -lt 2 ]]; then
-    pdie "Option requires an argument: $1"
-  fi
-  if [[ -n ${3:+set} ]]; then
-    if [[ $2 =~ $3 ]]; then
-      : OK
-    else
-      pdie "Invalid value for option: $1: $2"
-    fi
-  fi
-  if [[ -n ${4:+set} ]]; then
-    if [[ $2 =~ $4 ]]; then
-      pdie "Invalid value for option: $1: $2"
-    fi
-  fi
-}
-
 help_p=
 
 while [[ $# -gt 0 ]]; do
@@ -67,7 +48,13 @@ while [[ $# -gt 0 ]]; do
     exit 0
     ;;
   --log-level)
-    getopts_want_arg "$opt" ${1+"$1"} '^[0-7]$'
+    if [ $# -lt 2 ]; then
+      pdie "Option requires an argument: $opt"
+    fi
+    case $1 in
+      [0-7]) ;;
+      *) pdie "Invalid value for option: $opt: $1";;
+    esac
     SYSLOG_REDIRECT_LOG_LEVEL="$1"; shift
     export SYSLOG_REDIRECT_LOG_LEVEL
     ;;