From dad18c78cb52afe5428abf5403725118a285e641 Mon Sep 17 00:00:00 2001
From: "emellor@leeni.uk.xensource.com" <emellor@leeni.uk.xensource.com>
Date: Mon, 28 Nov 2005 11:05:07 +0000
Subject: [PATCH] Change uses of \s within sed regexps -- some versions of sed
 do not support this escape.

Allow the vif-nat and vif-route scripts to have netdev specified, rather than
hard-coding eth0.

Signed-off-by: Ewan Mellor <ewan@xensource.com>
---
 tools/examples/README.incompatibilities |  6 +++++
 tools/examples/vif-common.sh            | 34 +++++++++++++++++++++++++
 tools/examples/vif-nat                  |  2 +-
 tools/examples/vif-route                |  2 +-
 4 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/tools/examples/README.incompatibilities b/tools/examples/README.incompatibilities
index 2d2c9503cf..87b2dbd62e 100644
--- a/tools/examples/README.incompatibilities
+++ b/tools/examples/README.incompatibilities
@@ -23,3 +23,9 @@ appropriately.  See xen-network-common.sh for details.
 Gentoo doesn't have ifup/ifdown; appropriate alternatives are defined in
 xen-network-common.sh.
 
+
+sed
+---
+
+\s is not supported in regexps on Debian etch (sed 4.1.2), Ubuntu 4.10.  We
+hand-craft character classes instead.
diff --git a/tools/examples/vif-common.sh b/tools/examples/vif-common.sh
index f7a488082a..18a0b6c88e 100644
--- a/tools/examples/vif-common.sh
+++ b/tools/examples/vif-common.sh
@@ -103,3 +103,37 @@ function handle_iptable()
       frob_iptable
   fi
 }
+
+
+##
+# ip_of interface
+#
+# Print the IP address currently in use at the given interface, or nothing if
+# the interface is not up.
+#
+function ip_of()
+{
+  ip addr show "$1" | sed -n 's/^.*inet \([0-9.]*\).*$/\1/p'
+}
+
+
+##
+# dom0_ip
+#
+# Print the IP address of the interface in dom0 through which we are routing.
+# This is the IP address on the interface specified as "netdev" as a parameter
+# to these scripts, or eth0 by default.  This function will call fatal if no
+# such interface could be found.
+#
+function dom0_ip()
+{
+  local nd=${netdev:-eth0}
+  local result=$(ip_of "$nd")
+  if [ -z "$result" ]
+  then
+      fatal
+"$netdev is not up.  Bring it up or specify another interface with " \
+"netdev=<if> as a parameter to $0."
+  fi
+  echo "$result"
+}
diff --git a/tools/examples/vif-nat b/tools/examples/vif-nat
index 653038f223..f94829689c 100644
--- a/tools/examples/vif-nat
+++ b/tools/examples/vif-nat
@@ -37,7 +37,7 @@ netmask=$netmask.$(( (($intmask & 0x00FF0000)) >> 16 ))
 netmask=$netmask.$(( (($intmask & 0x0000FF00)) >> 8 ))
 netmask=$netmask.$(( $intmask & 0x000000FF ))
 
-main_ip=$(ip addr show eth0 | sed -e '/inet /!d;s/^.*inet \([^\s*]\)\s.*$/\1/')
+main_ip=$(dom0_ip)
 
 case "$command" in
     online)
diff --git a/tools/examples/vif-route b/tools/examples/vif-route
index 84a6f2d0c6..d733119d30 100755
--- a/tools/examples/vif-route
+++ b/tools/examples/vif-route
@@ -23,7 +23,7 @@
 dir=$(dirname "$0")
 . "$dir/vif-common.sh"
 
-main_ip=$(ip addr show eth0 | sed -e '/inet /!d;s/^.*inet \([^\s*]\)\s.*$/\1/')
+main_ip=$(dom0_ip)
 
 case "$command" in
     online)
-- 
2.30.2