[PATCH 2/2] nodewatcher: Prevent multiple instances at the same time

[robert]

Hi Adrian,

hier auch

Reviewed-by: Robert Langhammer <rlanghammer at web.de>

Am 31.10.18 um 17:35 schrieb Adrian Schmutzler:
> This is based on the configurehood-Patch from Tim Niemeyer.
>
> Signed-off-by: Adrian Schmutzler <freifunk at adrianschmutzler.de>
> ---
>  src/packages/fff/fff-nodewatcher/Makefile                   |  2 +-
>  src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher | 12 ++++++++++--
>  2 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/src/packages/fff/fff-nodewatcher/Makefile b/src/packages/fff/fff-nodewatcher/Makefile
> index 12ccb0f6..7f989fdb 100644
> --- a/src/packages/fff/fff-nodewatcher/Makefile
> +++ b/src/packages/fff/fff-nodewatcher/Makefile
> @@ -1,7 +1,7 @@
>  include $(TOPDIR)/rules.mk
>  
>  PKG_NAME:=fff-nodewatcher
> -PKG_VERSION:=48
> +PKG_VERSION:=49
>  PKG_RELEASE:=1
>  
>  PKG_BUILD_DIR:=$(BUILD_DIR)/$(PKG_NAME)
> diff --git a/src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher b/src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher
> index c0ae57b8..b0b67e1a 100755
> --- a/src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher
> +++ b/src/packages/fff/fff-nodewatcher/files/usr/sbin/nodewatcher
> @@ -2,10 +2,18 @@
>  # Netmon Nodewatcher (C) 2010-2012 Freifunk Oldenburg
>  # License; GPL v3
>  
> -SCRIPT_VERSION="48"
> -
>  test -f /tmp/started || exit
>  
> +# Allow only one instance
> +lockfile="/var/lock/${0##*/}.lock"
> +if ! lock -n "$lockfile"; then
> +        echo "Only one instance of $0 allowed."
> +        exit 1
> +fi
> +trap "lock -u \"$lockfile\"" INT TERM EXIT
> +
> +SCRIPT_VERSION="49"
> +
>  #Get the configuration from the uci configuration file
>  #If it does not exists, then get it from a normal bash file with variables.
>  if [ -f /etc/config/nodewatcher ];then