From d87bf146cca2c78005cf3c915cbee3cf4a985ad9 Mon Sep 17 00:00:00 2001
From: Sebastian Harl <sh@tokkee.org>
Date: Mon, 9 Jan 2012 11:16:19 +0100
Subject: [PATCH] build system, ipvs plugin: Check for linux/ip_vs.h as well.

Also, try to find ip_vs.h without using KERNEL_CFLAGS at first. The Linux
kernel headers should not be used directly -- in current kernel versions this
generates warnings leading to build failures because of -Werror.
---
 configure.in    | 35 +++++++++++++++++++++++++++++------
 src/Makefile.am |  2 ++
 src/ipvs.c      |  4 +++-
 3 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/configure.in b/configure.in
index 254e7fdf..5618ef84 100644
--- a/configure.in
+++ b/configure.in
@@ -385,18 +385,36 @@ AC_CHECK_HEADERS(linux/netdevice.h, [], [],
 ])
 
 # For ipvs module
+have_linux_ip_vs_h="no"
 have_net_ip_vs_h="no"
 have_ip_vs_h="no"
+ip_vs_h_needs_kernel_cflags="no"
 if test "x$ac_system" = "xLinux"
 then
-	SAVE_CFLAGS="$CFLAGS"
-	CFLAGS="$CFLAGS $KERNEL_CFLAGS"
-
+	AC_CHECK_HEADERS(linux/ip_vs.h, [have_linux_ip_vs_h="yes"])
 	AC_CHECK_HEADERS(net/ip_vs.h, [have_net_ip_vs_h="yes"])
 	AC_CHECK_HEADERS(ip_vs.h, [have_ip_vs_h="yes"])
 
-	CFLAGS="$SAVE_CFLAGS"
+	if test "x$have_linux_ip_vs_h$have_net_ip_vs_h$have_ip_vs_h" = "xnonono" && test -d "$KERNEL_DIR"
+	then
+		SAVE_CFLAGS="$CFLAGS"
+		CFLAGS="$CFLAGS $KERNEL_CFLAGS"
+
+		AC_MSG_NOTICE([Did not find ip_vs.h. Trying again using headers from $KERNEL_DIR.])
+
+		AC_CHECK_HEADERS(linux/ip_vs.h, [have_linux_ip_vs_h="yes"])
+		AC_CHECK_HEADERS(net/ip_vs.h, [have_net_ip_vs_h="yes"])
+		AC_CHECK_HEADERS(ip_vs.h, [have_ip_vs_h="yes"])
+
+		if test "x$have_linux_ip_vs_h" = "xyes" || test "x$have_net_ip_vs_h" = "xyes" || test "x$have_ip_vs_h" = "xyes"
+		then
+			ip_vs_h_needs_kernel_cflags="yes"
+		fi
+
+		CFLAGS="$SAVE_CFLAGS"
+	fi
 fi
+AM_CONDITIONAL(IP_VS_H_NEEDS_KERNEL_CFLAGS, test "x$ip_vs_h_needs_kernel_cflags" = "xyes")
 
 # For quota module
 AC_CHECK_HEADERS(sys/ucred.h, [], [],
@@ -4031,7 +4049,7 @@ then
 	plugin_vserver="yes"
 	plugin_wireless="yes"
 
-	if test "x$have_net_ip_vs_h" = "xyes" || test "x$have_ip_vs_h" = "xyes"
+	if test "x$have_linux_ip_vs_h" = "xyes" || test "x$have_net_ip_vs_h" = "xyes" || test "x$have_ip_vs_h" = "xyes"
 	then
 		plugin_ipvs="yes"
 	fi
@@ -4441,11 +4459,16 @@ AC_SUBST(LOAD_PLUGIN_CSV)
 
 dnl ip_vs.h
 if test "x$ac_system" = "xLinux" \
-	&& test "x$have_net_ip_vs_h$have_ip_vs_h" = "xnono"
+	&& test "x$have_linux_ip_vs_h$have_net_ip_vs_h$have_ip_vs_h" = "xnonono"
 then
 	enable_ipvs="$enable_ipvs (ip_vs.h not found)"
 fi
 
+if test "x$ip_vs_h_needs_kernel_cflags" = "xyes"
+then
+	enable_ipvs="$enable_ipvs (needs $KERNEL_CFLAGS)"
+fi
+
 dnl Perl bindings
 AC_ARG_WITH(perl-bindings, [AS_HELP_STRING([--with-perl-bindings@<:@=OPTIONS@:>@], [Options passed to "perl Makefile.PL".])],
 [
diff --git a/src/Makefile.am b/src/Makefile.am
index c6b0538d..0c427dc8 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -438,7 +438,9 @@ endif
 if BUILD_PLUGIN_IPVS
 pkglib_LTLIBRARIES += ipvs.la
 ipvs_la_SOURCES = ipvs.c
+if IP_VS_H_NEEDS_KERNEL_CFLAGS
 ipvs_la_CFLAGS = $(AM_CFLAGS) $(KERNEL_CFLAGS)
+endif
 ipvs_la_LDFLAGS = -module -avoid-version
 collectd_LDADD += "-dlopen" ipvs.la
 collectd_DEPENDENCIES += ipvs.la
diff --git a/src/ipvs.c b/src/ipvs.c
index 87eee108..7bd8c698 100644
--- a/src/ipvs.c
+++ b/src/ipvs.c
@@ -45,7 +45,9 @@
 #endif /* HAVE_NETINET_IN_H */
 
 /* this can probably only be found in the kernel sources */
-#if HAVE_NET_IP_VS_H
+#if HAVE_LINUX_IP_VS_H
+# include <linux/ip_vs.h>
+#elif HAVE_NET_IP_VS_H
 # include <net/ip_vs.h>
 #elif HAVE_IP_VS_H
 # include <ip_vs.h>
-- 
2.30.2