From bb8c7c599cdb2f4d8d2410772ba5b3ea68b1eb2f Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Tue, 12 Jan 2016 16:41:26 +0000
Subject: [PATCH 1/4] Revert "don't launch anything when plugin is running"

This reverts commit 3ade796e8d18a9d4253ce464463dd94114300052.
---
 weave | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/weave b/weave
index c37f332d..19f826e8 100755
--- a/weave
+++ b/weave
@@ -1846,11 +1846,14 @@ EOF
         deprecation_warnings "$@"
         check_not_running router $CONTAINER_NAME        $BASE_IMAGE
         check_not_running proxy  $PROXY_CONTAINER_NAME  $BASE_EXEC_IMAGE
-        check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE
         COMMON_ARGS=$(common_launch_args "$@")
         launch_router "$@"
         launch_proxy  $COMMON_ARGS
-        plugin_disabled || launch_plugin $COMMON_ARGS
+        # Allow an existing plugin to keep running, because we run it with restart=always
+        if ! plugin_disabled ; then
+            check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE 
+            launch_plugin $COMMON_ARGS
+        fi
         ;;
     launch-router)
         deprecation_warnings "$@"

From 517a2e0e0a0bdc7495af3c1b90fb78170e5c6328 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Tue, 12 Jan 2016 16:49:57 +0000
Subject: [PATCH 2/4] Fix nonzero exit code for a pre-existing plugin on
 launch; do this purely for the 'plugin running' case, not 'restarting' etc.

---
 weave | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/weave b/weave
index 19f826e8..786f8999 100755
--- a/weave
+++ b/weave
@@ -909,22 +909,22 @@ check_not_running() {
     case ${RUN_STATUS%:*} in
         "true restarting $3")
             echo "$2 is restarting; you can stop it with 'weave stop-$1'." >&2
-            exit 1
+            return 3
             ;;
         "true "*" $3")
             echo "$2 is already running; you can stop it with 'weave stop-$1'." >&2
-            exit 1
+            return 1
             ;;
         "false "*" $3")
             docker rm $2 >/dev/null
             ;;
         true*)
             echo "Found another running container named '$2'. Aborting." >&2
-            exit 1
+            return 2
             ;;
         false*)
             echo "Found another container named '$2'. Aborting." >&2
-            exit 1
+            return 2
             ;;
     esac
 }
@@ -1851,8 +1851,11 @@ EOF
         launch_proxy  $COMMON_ARGS
         # Allow an existing plugin to keep running, because we run it with restart=always
         if ! plugin_disabled ; then
-            check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE 
-            launch_plugin $COMMON_ARGS
+            if check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE ; then
+                launch_plugin $COMMON_ARGS
+            else
+                [ $? -lt 2 ] || exit 1
+            fi
         fi
         ;;
     launch-router)

From 3daceac668ff3955b9dea9482b6441dc7f365963 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Wed, 13 Jan 2016 10:03:43 +0000
Subject: [PATCH 3/4] Allow pre-existing plugin on 'weave launch-plugin'

---
 weave | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/weave b/weave
index 786f8999..a96e2787 100755
--- a/weave
+++ b/weave
@@ -1689,7 +1689,14 @@ stop_proxy() {
     stop $PROXY_CONTAINER_NAME "Proxy"
 }
 
-launch_plugin() {
+launch_plugin_if_not_running() {
+    retval=0
+    check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE || retval=$?
+    # If an existing plugin is running (we start it with restart=always), return its ID
+    [ $retval = 1 ] && PLUGIN_CONTAINER=$(container_id $PLUGIN_CONTAINER_NAME) && return 0
+    # Any other kind of error code from check_not_running is a failure.
+    [ $retval -gt 0 ] && return $retval
+
     PLUGIN_CONTAINER=$(docker run --privileged -d --name=$PLUGIN_CONTAINER_NAME \
         --restart=always \
         --net=host \
@@ -1849,14 +1856,7 @@ EOF
         COMMON_ARGS=$(common_launch_args "$@")
         launch_router "$@"
         launch_proxy  $COMMON_ARGS
-        # Allow an existing plugin to keep running, because we run it with restart=always
-        if ! plugin_disabled ; then
-            if check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE ; then
-                launch_plugin $COMMON_ARGS
-            else
-                [ $? -lt 2 ] || exit 1
-            fi
-        fi
+        plugin_disabled || launch_plugin_if_not_running $COMMON_ARGS
         ;;
     launch-router)
         deprecation_warnings "$@"
@@ -1879,8 +1879,7 @@ EOF
         echo $PROXY_CONTAINER
         ;;
     launch-plugin)
-        check_not_running plugin $PLUGIN_CONTAINER_NAME $BASE_PLUGIN_IMAGE
-        launch_plugin "$@"
+        launch_plugin_if_not_running "$@"
         echo $PLUGIN_CONTAINER
         ;;
     env|proxy-env)

From b055c9a4a2341f7333276af3b2b412f5870f41c7 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Wed, 13 Jan 2016 10:33:49 +0000
Subject: [PATCH 4/4] Fool-proofing

---
 weave | 1 +
 1 file changed, 1 insertion(+)

diff --git a/weave b/weave
index a96e2787..7e98cb51 100755
--- a/weave
+++ b/weave
@@ -1853,6 +1853,7 @@ EOF
         deprecation_warnings "$@"
         check_not_running router $CONTAINER_NAME        $BASE_IMAGE
         check_not_running proxy  $PROXY_CONTAINER_NAME  $BASE_EXEC_IMAGE
+        # Don't check the plugin here, since we start it with `--restart=always`
         COMMON_ARGS=$(common_launch_args "$@")
         launch_router "$@"
         launch_proxy  $COMMON_ARGS