From c7bf21cbf190df6d5a9f8a355de46009bde02b19 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Mayer?= <jmayer@loplof.de>
Date: Tue, 11 Sep 2012 10:48:43 +0000
Subject: [PATCH] Differentiate between libnl versions. Feature parity with
 autofoo for libnl.

svn path=/trunk/; revision=44876
---
 cmake/modules/FindNL.cmake | 91 ++++++++++++++++++++++++--------------
 1 file changed, 57 insertions(+), 34 deletions(-)

diff --git a/cmake/modules/FindNL.cmake b/cmake/modules/FindNL.cmake
index 9eeab4f1ae..54531ecaa1 100644
--- a/cmake/modules/FindNL.cmake
+++ b/cmake/modules/FindNL.cmake
@@ -1,9 +1,13 @@
 #
 # $Id$
 #
-# - Find netlink
 # Find the native netlink includes and library
 #
+# If they exist, differentiate between versions 1,2 and 3.
+# Version 1 does not have netlink/version.h
+# Version 3 does have the major version number as a suffix
+#   to the libnl name (libnl-3)
+#
 #  NL_INCLUDE_DIRS - where to find libnl.h, etc.
 #  NL_LIBRARIES    - List of libraries when using libnl3.
 #  NL_FOUND        - True if libnl found.
@@ -12,51 +16,72 @@ IF (NL_LIBRARIES AND NL_INCLUDE_DIRS )
   # in cache already
   SET(NL_FOUND TRUE)
 ELSE (NL_LIBRARIES AND NL_INCLUDE_DIRS )
-
   SET( SEARCHPATHS
       /opt/local
       /sw
       /usr
       /usr/local
   )
-
   FIND_PATH( NL_INCLUDE_DIR
     PATH_SUFFIXES
       include/libnl3
     NAMES
-      netlink/version.h netlink/netlink.h
+      netlink/version.h
     PATHS
       $(SEARCHPATHS)
   )
-
-  FIND_LIBRARY( NL_LIBRARY
-    NAMES
-      nl-3 nl
-    PATH_SUFFIXES
-      lib64 lib
-    PATHS
-      $(SEARCHPATHS)
-  )
-
-  FIND_LIBRARY( NLGENL_LIBRARY
-    NAMES
-      nl-genl-3 nl-genl
-    PATH_SUFFIXES
-      lib64 lib
-    PATHS
-      $(SEARCHPATHS)
-  )
-
-  FIND_LIBRARY( NLROUTE_LIBRARY
-    NAMES
-      nl-route-3 nl-route
-    PATH_SUFFIXES
-      lib64 lib
-    PATHS
-      $(SEARCHPATHS)
-  )
-
+  # NL version >= 2
+  IF ( NL_INCLUDE_DIR )
+    FIND_LIBRARY( NL_LIBRARY
+      NAMES
+        nl-3 nl
+      PATH_SUFFIXES
+        lib64 lib
+      PATHS
+        $(SEARCHPATHS)
+    )
+    FIND_LIBRARY( NLGENL_LIBRARY
+      NAMES
+        nl-genl-3 nl-genl
+      PATH_SUFFIXES
+        lib64 lib
+      PATHS
+        $(SEARCHPATHS)
+    )
+    FIND_LIBRARY( NLROUTE_LIBRARY
+      NAMES
+        nl-route-3 nl-route
+      PATH_SUFFIXES
+        lib64 lib
+      PATHS
+        $(SEARCHPATHS)
+    )
+    STRING(REGEX REPLACE ".*nl-([^.,;]*).*" "\\1" NLSUFFIX ${NL_LIBRARY})
+    IF ( NLSUFFIX )
+      SET( HAVE_LIBNL3 1 )
+    ELSE ( NLSUFFIX )
+      SET( HAVE_LIBNL2 1 )
+    ENDIF (NLSUFFIX )
+  ELSE( NL_INCLUDE_DIR )
+    # NL version 1 ?
+    FIND_PATH( NL_INCLUDE_DIR
+      NAMES
+        netlink/netlink.h
+      PATHS
+        $(SEARCHPATHS)
+    )
+    FIND_LIBRARY( NL_LIBRARY
+      NAMES
+        nl
+      PATH_SUFFIXES
+        lib64 lib
+      PATHS
+        $(SEARCHPATHS)
+    )
+    SET( HAVE_LIBNL1 1 )
+  ENDIF( NL_INCLUDE_DIR )
 ENDIF(NL_LIBRARIES AND NL_INCLUDE_DIRS)
+# MESSAGE(STATUS "LIB Found: ${NL_LIBRARY}, Suffix: ${NLSUFFIX}\n  1:${HAVE_LIBNL1}, 2:${HAVE_LIBNL2}, 3:${HAVE_LIBNL3}.")
 
 # handle the QUIETLY and REQUIRED arguments and set NL_FOUND to TRUE if
 # all listed variables are TRUE
@@ -66,8 +91,6 @@ FIND_PACKAGE_HANDLE_STANDARD_ARGS(NL DEFAULT_MSG NL_LIBRARY NL_INCLUDE_DIR)
 IF(NL_FOUND)
   SET( NL_LIBRARIES ${NLGENL_LIBRARY} ${NLROUTE_LIBRARY} ${NL_LIBRARY} )
   SET( NL_INCLUDE_DIRS ${NL_INCLUDE_DIR})
-# FIXME: Differentiate between libnl versions
-  SET( HAVE_LIBNL3 1 )
 ELSE()
   SET( NL_LIBRARIES )
   SET( NL_INCLUDE_DIRS )