#!/bin/sh
-# Copyright 2018, 2019 Paul Hänsch
+# Copyright 2018, 2019, 2021 Paul Hänsch
#
# This is a file format helper, part of CGIlite.
#
'
LOCK(){
- local lock timeout block
- lock="${1}.lock"
- timeout="${2-20}"
+ local lock="${1}.lock" timeout="${2-20}" block
if [ \! -w "${lock%/*}" ] || [ -e "$lock" -a \! -f "$lock" ]; then
debug "Impossible to get lock: $lock"
if [ "$block" = $$ ]; then
return 0
elif ! { ps -eo pid |grep -qwF "$block"; }; then
- debug "Overriding stale lock: $lock"
+ debug "Trying to override stale lock: $lock"
if LOCK "$lock" 1; then
rm -- "$lock"
RELEASE "$lock"
fi
else
timeout=$((timeout - 1))
- sleep 1
+ [ $timeout -gt 0 ] && sleep 1
fi
done
}
RELEASE(){
- local lock block
- lock="${1}.lock"
+ local lock="${1}.lock" block
read block <"$lock"
if [ "$block" = $$ ]; then