Daniel P. Berrange wrote:
On Mon, May 17, 2010 at 04:25:43PM +0200, Jim Meyering wrote:
This is required for any kernel prior to 2.6.19, since <linux/magic.h> didn't exist back then. Now that file is provided by the kernel-headers package.
From d14ef1669968ffeb65076b007e318934ed99aa61 Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyering@redhat.com> Date: Mon, 17 May 2010 16:17:08 +0200 Subject: [PATCH] build: avoid compile failure on linux kernels older than 2.6.19
* configure.ac: Check for <linux/magic.h>. * src/util/storage_file.c: Include <linux/magic.h> only if present. Linux kernels prior to 2.6.19 lacked it. [__linux__] (NFS_SUPER_MAGIC): Define if not already defined. --- configure.ac | 2 +- src/util/storage_file.c | 7 ++++++- 2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/configure.ac b/configure.ac index c187420..ebd2082 100644 --- a/configure.ac +++ b/configure.ac @@ -108,7 +108,7 @@ LIBS=$old_libs
dnl Availability of various common headers (non-fatal if missing). AC_CHECK_HEADERS([pwd.h paths.h regex.h sys/syslimits.h \ - termios.h sys/poll.h syslog.h mntent.h net/ethernet.h]) + termios.h sys/poll.h syslog.h mntent.h net/ethernet.h linux/magic.h])
dnl Where are the XDR functions? dnl If portablexdr is installed, prefer that. diff --git a/src/util/storage_file.c b/src/util/storage_file.c index 5f15a64..a07bedc 100644 --- a/src/util/storage_file.c +++ b/src/util/storage_file.c @@ -27,7 +27,9 @@ #include <unistd.h> #include <fcntl.h> #ifdef __linux__ -# include <linux/magic.h> +# if HAVE_LINUX_MAGIC_H +# include <linux/magic.h> +# endif
Don't bother with this - just kill this include off completely. It is a waste of time using it if we can't rely on it existing & have to re-define everything ourselves.
I admit that those numbers will probably never change, but I see including the recommended/modern header as the preferred approach. Then, eventually when the old systems are no longer relevant (yeah, in a long time) we'll be able to remove our hackish define-if-required code.