[libvirt] [PATCH] Rework configure logic for virtualport support

[Stefan Berger]

  In this patch I am reworking the logic around detecting virtual port 
support and requiring the libnl dependency.

- It requires --with-macvtap and displays an error in case of 
--without-macvtap --with-virtualport.
- It tests for availability of certain data in include files and 
displays an error in case the include file is not at the correct level 
and --with-virtualport was chosen
- displays 'checking' messages for macvtap and virtualport support and 
results
- libnl support is required when macvtap is found or requested; if libnl 
is not there, please supply without-macvtap

Signed-off-by: Stefan Berger <stefanb at us.ibm.com>


diff --git a/configure.ac b/configure.ac
index 6100610..d94b510 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2058,6 +2058,7 @@ AC_ARG_WITH([macvtap],
    [with_macvtap=${withval}],
    [with_macvtap=check])

+AC_MSG_CHECKING([whether to compile with macvtap support])
  if test "$with_macvtap" != "no" ; then
      AC_TRY_COMPILE([ #include <sys/socket.h>
                       #include <linux/rtnetlink.h> ],
@@ -2075,19 +2076,31 @@ if test "$with_macvtap" != "no" ; then
      AC_DEFINE_UNQUOTED([WITH_MACVTAP], $val, [whether macvtap support 
is enabled])
  fi
  AM_CONDITIONAL([WITH_MACVTAP], [test "$with_macvtap" = "yes"])
+AC_MSG_RESULT([$with_macvtap])

-AC_TRY_COMPILE([ #include <sys/socket.h>
-                 #include <linux/rtnetlink.h> ],
-                 [ int x = IFLA_PORT_MAX; ],
-                 [ with_virtualport=yes ],
-                 [ with_virtualport=no ])
-if test "$with_virtualport" = "yes"; then
-    val=1
-else
-    val=0
+val=0
+if test "$with_virtualport" != "no"; then
+    if test "$with_macvtap" = "no"; then
+        AC_MSG_ERROR([--with-virtualport requires --with-macvtap])
+    fi
+    AC_MSG_CHECKING([whether to compile with virtual port support])
+    AC_TRY_COMPILE([ #include <sys/socket.h>
+                     #include <linux/rtnetlink.h> ],
+                     [ int x = IFLA_PORT_MAX; ],
+                     [ with_virtualport=yes ],
+                     [ if test "$with_virtualport" = "yes" ; then
+                         AC_MSG_ERROR([Installed linux headers don't 
show support for virtual port support.])
+                       fi
+                       with_virtualport=no ])
+    if test "$with_virtualport" = "yes"; then
+        val=1
+    else
+        val=0
+    fi
+    AC_DEFINE_UNQUOTED([WITH_VIRTUALPORT], $val,
+                       [whether vsi vepa support is enabled])
+    AC_MSG_RESULT([$with_virtualport])
  fi
-AC_DEFINE_UNQUOTED([WITH_VIRTUALPORT], $val,
-                   [whether vsi vepa support is enabled])
  AM_CONDITIONAL([WITH_VIRTUALPORT], [test "$with_virtualport" = "yes"])


@@ -2096,7 +2109,7 @@ dnl netlink library
  LIBNL_CFLAGS=""
  LIBNL_LIBS=""

-if test "$with_macvtap" = "yes" || test "$with_virtualport" = "yes"; then
+if test "$with_macvtap" = "yes"; then
      PKG_CHECK_MODULES([LIBNL], [libnl-1 >= $LIBNL_REQUIRED], [
      ], [
          AC_MSG_ERROR([libnl >= $LIBNL_REQUIRED is required for macvtap 
support])