use pure bash for uppercasing strings. fixes #36

Author: ehough

Diff for: CHANGELOG.md

@@ -4,6 +4,11 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [unreleased]
+
+### Changed
+* Use pure Bash for uppercasing strings ([#36](https://github.com/ehough/docker-nfs-server/issues/36))
+
 ## [2.2.1] - 2019-03-15
 
 ### Fixed

Diff for: entrypoint.sh

@@ -5,7 +5,7 @@
 # https://hub.docker.com/r/erichough/nfs-server
 # https://github.com/ehough/docker-nfs-server
 #
-# Copyright (C) 2017-2019  Eric D. Hough
+# Copyright (C) 2017-2020  Eric D. Hough
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -75,16 +75,6 @@ readonly STATE_NFS_VERSION='nfs_version'
 declare -A state
 
 
-######################################################################################
-### string utils
-######################################################################################
-
-toupper() {
-
-  echo "$1" | awk '{ print toupper($0) }'
-}
-
-
 ######################################################################################
 ### logging
 ######################################################################################
@@ -110,7 +100,7 @@ log_header() {
 
   echo "
 ==================================================================
-      $(toupper "$1")
+      ${1^^}
 =================================================================="
 }
 
@@ -341,7 +331,8 @@ assert_port() {
 init_state_logging() {
 
   # if the user didn't request a specific log level, the default is INFO
-  local -r normalized_log_level=$(toupper "${!ENV_VAR_NFS_LOG_LEVEL:-$LOG_LEVEL_INFO}")
+  local incoming_log_level="${!ENV_VAR_NFS_LOG_LEVEL:-$LOG_LEVEL_INFO}"
+  local -r normalized_log_level="${incoming_log_level^^}"
 
   if ! echo "$normalized_log_level" | grep -Eq 'DEBUG|INFO'; then
     bail "the only acceptable values for $ENV_VAR_NFS_LOG_LEVEL are: DEBUG, INFO"