tools: add macosx-firwall script to avoid popups

Currently, there are a number of popups that get displayed when running
the tests asking to accept incoming network connections. Rules can be
added manually to the socket firewall on Mac OS X but getting this right
might not be obvious and quite a lot of time can be wasted trying to get
the rules right. This script hopes to simplify things a little so that
it can be re-run when needed.

The script should be runnable from both the projects root directory and
from the tools directory, for example:
$ sudo ./tools/macosx-firewall.sh

Fixes: nodejs#8911

BUILDING.md

@@ -23,6 +23,7 @@ On OS X, you will also need:
   * You also need to install the `Command Line Tools` via Xcode. You can find
     this under the menu `Xcode -> Preferences -> Downloads`
   * This step will install `gcc` and the related toolchain containing `make`
+  * You may want to setup [firewall rules](tools/macosx-firewall.sh) to avoid popups asking to accept incoming network connections when running tests.
 
 On FreeBSD and OpenBSD, you may also need:
 * libexecinfo

tools/macosx-firewall.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+# Script that adds rules to Mac OS X Socket Firewall to avoid
+# popups asking to accept incoming network connections when
+# running tests.
+SFW="/usr/libexec/ApplicationFirewall/socketfilterfw"
+TOOLSDIR="`dirname \"$0\"`"
+TOOLSDIR="`( cd \"$TOOLSDIR\" && pwd) `"
+ROOTDIR="`( cd \"$TOOLSDIR/..\" && pwd) `"
+OUTDIR=$TOOLSDIR/../out
+OUTDIR="`( cd \"$OUTDIR\" && pwd) `"
+NODE_RELEASE=$OUTDIR/Release/node
+NODE_DEBUG=$OUTDIR/Debug/node
+NODE_LINK=$ROOTDIR/node
+
+if [ -f $SFW ];
+then
+  # Duplicating these commands on purpose as the symbolic link node might be
+  # linked to either out/Debug/node or out/Release/node depending on the
+  # BUILDTYPE.
+  $SFW --remove $NODE_DEBUG
+  $SFW --remove $NODE_DEBUG
+  $SFW --remove $NODE_RELEASE
+  $SFW --remove $NODE_RELEASE
+  $SFW --remove $NODE_LINK
+
+  $SFW --add $NODE_DEBUG
+  $SFW --add $NODE_RELEASE
+  $SFW --add $NODE_LINK
+
+  $SFW --unblock $NODE_DEBUG
+  $SFW --unblock $NODE_RELEASE
+  $SFW --unblock $NODE_LINK
+else
+  echo "SocketFirewall not found in location: $SFW"
+fi