fixed a serious bug and prevented simultaneous runs of the main script

door.sh

@@ -1,28 +1,82 @@
-#! /bin/sh
+#! /bin/bash
 
-cd /etc/door/
 export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
 
 OPEN_INDICATOR=/tmp/door_status_open
 CLOSED_INDICATOR=/tmp/door_status_closed
 
+DELAY=10
+DATE_STRING="$(date +%s)#$(date +"%F %X")"
+TIMEOUT=30
+LOCKDIR="/var/lock"
+
+lock_file() {
+        OUTFILE=$1
+        OUTFILE_LOCK="${LOCKDIR}/$(readlink -f $OUTFILE | sed -e "s/\//\!/g").lock"
+        TIMEOUT_LOCK=$TIMEOUT
+        while [ $(mkdir "$OUTFILE_LOCK" 2> /dev/null; echo $? ) -ne 0 -a $TIMEOUT_LOCK -gt 0 ]; do
+                TIMEOUT_LOCK=$(($TIMEOUT_LOCK-1))
+                if [ -f "$OUTFILE_LOCK/lastaction" -a ! -d "$OUTFILE_LOCK/timeout"  ] >> /dev/null 2>&1; then
+                        FILEAGE=$(($(date +%s) - $(stat -c '%Y' "$OUTFILE_LOCK/lastaction" || echo $(date +%s) 2> /dev/null )))
+                        TIMEOUT_LOCK=$(($TIMEOUT-$FILEAGE))
+                fi
+                if [ $TIMEOUT_LOCK -le 0 ]; then
+                        if [ $(mkdir "$OUTFILE_LOCK/timeout" >> /dev/null 2>&1; echo $? ) -ne 0 ]; then
+                                TIMEOUTAGE_LOCK=$(($(date +%s) - $(stat -c '%Y' "$OUTFILE_LOCK/timeout")))
+                                if [ $TIMEOUTAGE_LOCK -gt $TIMEOUT ]; then
+                                        if [ $(rm -rf "$OUTFILE_LOCK/timeout" >> /dev/null 2>&1; echo $? ) -ne 0 ]; then
+                                                TIMEOUT_LOCK=$TIMEOUT
+                                        else
+                                                TIMEOUT_LOCK=1
+                                        fi
+                                else
+                                        TIMEOUT_LOCK=$(($TIMEOUT-$TIMEOUTAGE_LOCK))
+                                fi
+                        fi
+                fi
+                sleep 1
+        done
+        if [ $TIMEOUT_LOCK -le 0 ]; then
+                echo "Timeout! Ignoring old \"$OUTFILE_LOCK\"." >&2
+        fi
+        touch "$OUTFILE_LOCK/lastaction"
+}
+
+unlock_file() {
+        OUTFILE=${1}
+        OUTFILE_LOCK="${LOCKDIR}/$(readlink -f $OUTFILE | sed -e "s/\//\!/g").lock"
+        rm -rf "$OUTFILE_LOCK"
+}
+
+cd $(dirname $0) || {
+    echo "konnte verzeichniss nicht wechseln"
+    exit 1
+}
+
+lock_file $OPEN_INDICATOR
+lock_file $CLOSED_INDICATOR
 if [ -f $OPEN_INDICATOR ]; then
 	LOCK_AGE=$(( $(date +%s)-$(stat -c %X $OPEN_INDICATOR) ))
 elif [ -f $CLOSED_INDICATOR ]; then
 	LOCK_AGE=$(( $(date +%s)-$(stat -c %X $CLOSED_INDICATOR) ))
 else
-	LOCK_AGE=15
+	LOCK_AGE=$DELAY
 fi
 
-if [ $LOCK_AGE -lt 15 ]; then
-	echo "please wait at least 15 seconds befor a second run of this script" >&2
+if [ $LOCK_AGE -lt $DELAY ]; then
+	echo "please wait at least $DELAY seconds before a second run of this script" >&2
+	unlock_file $OPEN_INDICATOR
+	unlock_file $CLOSED_INDICATOR
 	exit 1
 fi
 
-./door_verify.sh
-STATUS=$?
+if [ "$1" == "noverify" ]; then
+	STATUS=0
+else
+	./door_verify.sh
+	STATUS=$?
+fi
 if [ $STATUS -eq 0 ]; then
-	echo "opening door"
 	if [ -f $OPEN_INDICATOR ]; then
 		echo "closing door"
 		./door_lock.sh close
@@ -34,8 +88,17 @@ if [ $STATUS -eq 0 ]; then
 		rm $CLOSED_INDICATOR
 		touch $OPEN_INDICATOR	
 	fi
+	unlock_file $OPEN_INDICATOR
+	unlock_file $CLOSED_INDICATOR
 	exit 0
 else
 	echo "the lock won't move" >&2
+	if [ -f $OPEN_INDICATOR ]; then
+		touch $OPEN_INDICATOR
+	else
+		touch $CLOSED_INDICATOR
+	fi
+	unlock_file $OPEN_INDICATOR
+	unlock_file $CLOSED_INDICATOR
 	exit 1
 fi