[Mesa-dev] [PATCH] Adding -enable-egl-dri2 option. Happy Chinese Spring Festival!

[Kristian Høgsberg]

On Thu, Feb 3, 2011 at 9:15 AM, Dan Nicholson <dbn.lists at gmail.com> wrote:
> On Thu, Feb 3, 2011 at 5:26 AM, Arthur Zhu
> <xiaoxiaomuyusajiangtian at gmail.com> wrote:
>>
>> Thanks your good suggestions.
>>
>> Arthur
>>
>>
>> From 7034307045f1d334e25adf7f739c5144a9afcb46 Mon Sep 17 00:00:00 2001
>> From: Arthur Zhu <xiaoxiaomuyusajiangtian at gmail.com>
>> Date: Thu, 3 Feb 2011 21:12:04 +0800
>> Subject: [PATCH] Adding -enable-egl-dri2 option.
>>
>> ---
>>  configure.ac |   26 ++++++++++++--------------
>>  1 files changed, 12 insertions(+), 14 deletions(-)
>>
>> diff --git a/configure.ac b/configure.ac
>> index 46938f4..bd50767 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -1091,6 +1091,12 @@ if test "x$enable_egl" = xno; then
>>          AC_MSG_ERROR([cannot enable OpenVG without EGL])
>>      fi
>>  fi
>> +
>> +AC_ARG_ENABLE([egl-dri2],
>> +    [AS_HELP_STRING([--enable-egl-dri2],
>> +        [enable EGL egl-dri2 driver @<:@default=disabled@:>@])],
>> +    [enable_egl_dri2="$enableval"],
>> +    [enable_egl_dri2=no])
>>  if test "x$enable_egl" = xyes; then
>>      SRC_DIRS="$SRC_DIRS egl"
>>      EGL_LIB_DEPS="$DLOPEN_LIBS -lpthread"
>> @@ -1100,21 +1106,13 @@ if test "x$enable_egl" = xyes; then
>>          if test "$mesa_driver" = xlib -o "$mesa_driver" = dri; then
>>              EGL_DRIVERS_DIRS="glx"
>>          fi
>> -
>> -        if test "$mesa_driver" = dri; then
>> +        if test "x$enable_egl_dri2" = xyes -a "$mesa_driver" = dri; then
>>              # build egl_dri2 when xcb-dri2 is available
>> -            PKG_CHECK_MODULES([XCB_DRI2], [x11-xcb xcb-dri2 xcb-xfixes],
>> -                      [have_xcb_dri2=yes],[have_xcb_dri2=no])
>> -            PKG_CHECK_MODULES([LIBUDEV], [libudev > 150],
>> -                      [have_libudev=yes],[have_libudev=no])
>> -
>> -            if test "$have_xcb_dri2" = yes; then
>> -                EGL_DRIVER_DRI2=dri2
>> -                DEFINES="$DEFINES -DHAVE_XCB_DRI2"
>> -                if test "$have_libudev" = yes; then
>> -                    DEFINES="$DEFINES -DHAVE_LIBUDEV"
>> -                fi
>> -            fi
>> +            PKG_CHECK_MODULES([XCB_DRI2], [x11-xcb xcb-dri2 xcb-xfixes])
>> +            EGL_DRIVER_DRI2=dri2
>> +            DEFINES="$DEFINES -DHAVE_XCB_DRI2"
>> +            PKG_CHECK_MODULES([LIBUDEV], [libudev > 150])
>> +            DEFINES="$DEFINES -DHAVE_LIBUDEV"
>
> I didn't notice this the first time, but there are a couple changes of
> the semantics. Now if you say --enable-egl-dri2, configure will fail
> if you don't have XCB_DRI2. I think that's OK since the user has to
> explicitly enable the option.

In fact, I think that's better because we've had problems in the past
with egl_dri2 not working on X11 because configure silently failed to
find the xcb devel headers.  Having an option to explicitly request
that and fail it not available is very useful.

> However, now the LIBUDEV dependency is
> unconditional, too. Is libudev required for egl-dri2?

It's required for drm-only (X-less) functionality of egl-dri2.  I
think it makes sense to split this option into --enable-egl-dri2-x11
and --enable-egl-dri2-drm, and then check for xcb and udev
respectively.

Kristian