From fe0731b10011075ab40960e13eb2ae5f39771e90 Mon Sep 17 00:00:00 2001 From: Ben Pfaff Date: Thu, 16 Feb 2012 10:34:55 -0800 Subject: [PATCH] configure: Try to extract kernel source directory from build Makefile. OVS needs to inspect the headers in the kernel source directory at build time. Debian keeps moving the source directory relative to the build directory and doesn't provide an obvious way to find the source directory, so in the past we've used some name-based heuristics to essentially guess where it is. This commit introduces a new heuristic that I hope will be more reliable: extracting the source directory from the Makefile in the build directory. In Debian's case, it looks like the Makefile generally contains a line of the form "MAKEARGS := -C O=". This commit extracts the source directory from that line. To avoid regressions this commit retains the older heuristics as fallbacks. CC: 659685@bugs.debian.org Reported-by: Thomas Goirand Signed-off-by: Ben Pfaff --- acinclude.m4 | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-) diff --git a/acinclude.m4 b/acinclude.m4 index 4c1b06544..69bb7727d 100644 --- a/acinclude.m4 +++ b/acinclude.m4 @@ -1,6 +1,6 @@ # -*- autoconf -*- -# Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks. +# Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. @@ -98,16 +98,23 @@ AC_DEFUN([OVS_CHECK_LINUX], [ else KSRC=$KBUILD if test ! -e $KSRC/include/linux/kernel.h; then - case `echo "$KBUILD" | sed 's,/*$,,'` in # ( - */build) - KSRC=`echo "$KBUILD" | sed 's,/build/*$,/source,'` - ;; # ( - *) - KSRC=`(cd $KBUILD && pwd -P) | sed 's,-[[^-]]*$,-common,'` - ;; - esac + # Debian kernel build Makefiles tend to include a line of the form: + # MAKEARGS := -C /usr/src/linux-headers-3.2.0-1-common O=/usr/src/linux-headers-3.2.0-1-486 + # First try to extract the source directory from this line. + KSRC=`sed -n 's/.*-C \([[^ ]]*\).*/\1/p' "$KBUILD"/Makefile` + if test ! -e "$KSRC"/include/linux/kernel.h; then + # Didn't work. Fall back to name-based heuristics that used to work. + case `echo "$KBUILD" | sed 's,/*$,,'` in # ( + */build) + KSRC=`echo "$KBUILD" | sed 's,/build/*$,/source,'` + ;; # ( + *) + KSRC=`(cd $KBUILD && pwd -P) | sed 's,-[[^-]]*$,-common,'` + ;; + esac + fi fi - if test ! -e $KSRC/include/linux/kernel.h; then + if test ! -e "$KSRC"/include/linux/kernel.h; then AC_MSG_ERROR([cannot find source directory (please use --with-linux-source)]) fi fi -- 2.43.0