added lock-util

bin/lock-util

@@ -0,0 +1 @@
+../files/lock-util

files/lock-util

@@ -0,0 +1,77 @@
+#!/bin/bash
+
+_help() {
+  echo '
+Usage: lock-util {lock-file} [-v] [command] [args]
+Commands:
+  create
+  exist                ( return 0 if lock exists )
+  old [age in seconds] ( return 0 if file younger than [args] seconds )
+  remove
+  -v as first argument sets very verbose mode
+ 
+'
+}
+LOCKFILE="$1"
+[[ "$2" = "-v" ]] && { 
+    VERBOSE=on
+    COMMAND="$3"
+    ARG="$4"
+} || {
+    COMMAND="$2"
+    ARG="$3"
+}
+BOXES=cat
+which boxes &>/dev/null && BOXES="boxes -d shell"
+
+_create() {
+    touch "$LOCKFILE"
+}
+_exist() {
+    test -f "$LOCKFILE"
+}
+_remove() {
+    rm "$LOCKFILE"
+}
+
+[[ $COMMAND = "create" ]] && {
+    _exist && {
+        [[ "$VERBOSE" = "on" ]] && echo "LOCK FILE EXISTS" | $BOXES
+        exit 1
+    }
+    _create
+    ec=$?
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -eq 0 ]] && echo "LOCK FILE CREATED" | $BOXES
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -ne 0 ]] && echo "UNABLE TO CREATE LOCK FILE" | $BOXES
+    exit $ec
+}
+
+[[ $COMMAND = "exist" ]] && {
+    _exist
+    ec=$?
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -eq 0 ]] && echo "LOCK FILE EXISTS" | $BOXES
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -ne 0 ]] && echo "LOCK FILE DOES NOT EXIST" | $BOXES
+    exit $ec
+}
+
+[[ $COMMAND = "old" ]] && { 
+    created=$( stat -c %Z "$LOCKFILE" )
+    now=$( date +%s )
+    age=$(( $now - $created ))
+    test $ARG -lt $age
+    ec=$?
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -eq 0 ]] && echo "LOCK FILE OLDER THAN $ARG s" | $BOXES
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -ne 0 ]] && echo "LOCK FILE YOUNGER THAN $ARG s" | $BOXES
+    exit $ec
+}
+
+[[ $COMMAND = "remove" ]] && {
+    _remove
+    ec=$?
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -eq 0 ]] && echo "LOCK FILE REMOVED" | $BOXES
+    [[ "$VERBOSE" = "on" ]] && [[ $ec -ne 0 ]] && echo "UNABLE TO REMOVE LOCK FILE" | $BOXES
+    exit $ec
+}
+
+echo Command not recognized
+_help