eliminate dependency on pipework

...and docker-ns (though we still leave the script around since it's
handy for debugging), and arping (as I have yet to encounter a
situation where it was required)

README.md

@@ -8,24 +8,14 @@ multiple containers, running anywhere.
 
 ## Installation
 
-Each host needs to have the following installed
+Each host needs to have `weave` from the `weaver` sub-directory
+installed in the root user's path, e.g.
 
-- `weave` and `docker-ns` from the `weaver` sub-directory. Install
-  these somewhere in the root user's path, e.g. `/usr/local/bin`.
-- [pipework][], by Jérôme Petazzoni. Install this in the same place as
-  the aforementioned scripts.
+    host# curl https://raw.githubusercontent.com/zettio/weave/master/weaver/weave \
+          > /usr/local/bin/weave; chmod a+x /usr/local/bin/weave
 
-[pipework]: https://raw.githubusercontent.com/jpetazzo/pipework/master/pipework
-
-e.g.
-
-    host# cp -a weaver/weave weaver/docker-ns /usr/local/bin
-    host# curl https://raw.githubusercontent.com/jpetazzo/pipework/master/pipework \
-          > /usr/local/bin/pipework; chmod a+x /usr/local/bin/pipework
-
-We also need `ethtool` and `arping`. On most systems these are
-installed already; if not then grab them via your favourite package
-manager.
+We also need `ethtool`. On most systems that is installed already; if
+not then grab it via your favourite package manager.
 
 ## Example
 

weaver/.gitignore

@@ -1,2 +1 @@
 weaver
-pipework

weaver/Makefile

@@ -13,10 +13,6 @@ docker-image: /tmp/weave.tar
 	sudo docker build -t zettio/weave .
 	sudo docker save zettio/weave > /tmp/weave.tar
 
-pipework:
-	wget --no-check-certificate -nv https://raw.github.com/jpetazzo/pipework/master/pipework
-	chmod +x pipework
-
 clean:
 	-sudo docker rmi zettio/weave
 	rm -f weaver pipework /tmp/weave.tar

weaver/weave

@@ -12,7 +12,7 @@ shift 2
 
 # pre-create bridge so we can set the MTU
 [ ! -d /sys/class/net/$BRIDGE ] && {
-    ip link add dev $BRIDGE type bridge > /dev/null 2>&1
+    ip link add dev $BRIDGE type bridge
     ip link set dev $BRIDGE address 7a:$(od -txC -An -N5 /dev/random | tr \  : | tail -c+2)
     # attempting to set the bridge MTU to a high value directly
     # fails. Bridges take the lowest MTU of their interfaces. So
@@ -42,8 +42,36 @@ case "$COMMAND" in
         ;;
 esac
 
-${SCRIPT_DIR}/pipework $BRIDGE -i $CONTAINER_IFNAME $CONTAINER $IPADDR 1>&2
+# the following borrows from https://github.com/jpetazzo/pipework
 
-${SCRIPT_DIR}/docker-ns $CONTAINER ethtool -K $IFACE tx off > /dev/null
+DOCKERPID=$(docker inspect --format='{{ .State.Pid }}' $CONTAINER)
+[ "$DOCKERPID" = 0 ] && {
+    echo "Docker inspect returned invalid PID 0"
+    exit 1
+}
+[ "$DOCKERPID" = "<no value>" ] && {
+    echo "Container $CONTAINER unknown to Docker."
+    exit 1
+}
+
+NSPID=$DOCKERPID
+
+[ ! -d /var/run/netns ] && mkdir -p /var/run/netns
+[ -f /var/run/netns/$NSPID ] && rm -f /var/run/netns/$NSPID
+ln -s /proc/$NSPID/ns/net /var/run/netns/$NSPID
+
+LOCAL_IFNAME="v${CONTAINER_IFNAME}pl${NSPID}"
+GUEST_IFNAME="v${CONTAINER_IFNAME}pg${NSPID}"
+ip link add name $LOCAL_IFNAME mtu $MTU type veth peer name $GUEST_IFNAME mtu $MTU
+ip link set $LOCAL_IFNAME master $BRIDGE
+ip link set $LOCAL_IFNAME up
+ip link set $GUEST_IFNAME netns $NSPID
+ip netns exec $NSPID ip link set $GUEST_IFNAME name $CONTAINER_IFNAME
+ip netns exec $NSPID ip addr add $IPADDR dev $CONTAINER_IFNAME
+ip netns exec $NSPID ip link set $CONTAINER_IFNAME up
+
+ip netns exec $NSPID ethtool -K $IFACE tx off > /dev/null
+
+[ -f /var/run/netns/$NSPID ] && rm -f /var/run/netns/$NSPID
 
 echo $CONTAINER