[PATCH] configure.ac: add option for xshmfence

[Matt Turner]

On Mon, Jul 7, 2014 at 5:18 AM, Ross Burton <ross.burton at intel.com> wrote:
> xshmfence is usable outside of DRI3, and is currently autodetected which isn't
> good for distributions where deterministic builds are aspired to.

s/aspired to/desired/ seems a lot less awkward.

>
> Signed-off-by: Ross Burton <ross.burton at intel.com>
> ---
>  configure.ac |   20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/configure.ac b/configure.ac
> index 2daa6be..fd1cf3f 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -648,6 +648,7 @@ AC_ARG_ENABLE(kdrive-kbd,     AS_HELP_STRING([--enable-kdrive-kbd], [Build kbd d
>  AC_ARG_ENABLE(kdrive-mouse,   AS_HELP_STRING([--enable-kdrive-mouse], [Build mouse driver for kdrive (default: auto)]), [KDRIVE_MOUSE=$enableval], [KDRIVE_MOUSE=auto])
>  AC_ARG_ENABLE(kdrive-evdev,   AS_HELP_STRING([--enable-kdrive-evdev], [Build evdev driver for kdrive (default: auto)]), [KDRIVE_EVDEV=$enableval], [KDRIVE_EVDEV=auto])
>  AC_ARG_ENABLE(libunwind,      AS_HELP_STRING([--enable-libunwind], [Use libunwind for backtracing (default: auto)]), [LIBUNWIND="$enableval"], [LIBUNWIND="auto"])
> +AC_ARG_ENABLE(xshmfence,      AS_HELP_STRING([--disable-xshmfence], [Disable xshmfence (default: auto)]), [WANT_XSHMFENCE="$enableval"], [WANT_XSHMFENCE="auto"])
>
>
>  dnl chown/chmod to be setuid root as part of build
> @@ -1235,18 +1236,19 @@ esac
>
>  AM_CONDITIONAL(BUSFAULT, test x"$BUSFAULT" = xyes)
>
> -PKG_CHECK_MODULES([XSHMFENCE], $XSHMFENCE,
> -                 [HAVE_XSHMFENCE=yes], [HAVE_XSHMFENCE=no])
> +HAVE_XSHMFENCE=no
> +if test "x$WANT_XSHMFENCE" != "xno"; then
> +       PKG_CHECK_MODULES([XSHMFENCE], $XSHMFENCE,
> +                         [HAVE_XSHMFENCE=yes], [HAVE_XSHMFENCE=no])
>
> +       if test "$WANT_XSHMFENCE,$HAVE_XSHMFENCE" = "yes,no"; then
> +               AC_MSG_ERROR([libxshmfence requested but not found.])
> +       fi
> +       AC_DEFINE(HAVE_XSHMFENCE, 1, [Have X Shared Memory Fence library])
> +       REQUIRED_LIBS="$REQUIRED_LIBS xshmfence"
> +fi

It looks like you're going to a lot of effort to avoid the
PKG_CHECK_MODULES if xshmfence is disabled. Any particular reason?

Does the pattern used for libunwind work instead?