gallium: Add pipe loader for device enumeration and driver multiplexing.

The goal is to have a uniform interface to create winsys and
pipe_screen instances for any driver, exposing the device enumeration
capabilities that might be supported by the operating system (for now
there's a "drm" back-end using udev and a "sw" back-end that always
returns the same built-in devices).

The typical use case of this library will be:
>
> struct pipe_loader_device devs[n];
> struct pipe_screen *screen;
>
> pipe_loader_probe(&devs, n);
>[pick some device from the array...]
>
> screen = pipe_loader_create_screen(dev, library_search_path);
>[do something with screen...]
>
> screen->destroy(screen);
> pipe_loader_release(&devs, N);
>

A part of the code was taken from targets/gbm/pipe_loader.c, which
will be removed and replaced with calls into this library by a future
commit.

1 files changed, 22 insertions, 0 deletions

diff --git a/configure.ac b/configure.ac
index 3bc59ca3e78..4b26e72d351 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1967,6 +1967,25 @@ if test "x$with_gallium_drivers" != x; then
     done
 fi
 
+if test "x$enable_gallium_loader" = xyes; then
+    GALLIUM_WINSYS_DIRS="$GALLIUM_WINSYS_DIRS sw/null"
+    GALLIUM_PIPE_LOADER_DEFINES="-DHAVE_PIPE_LOADER_SW"
+    GALLIUM_PIPE_LOADER_LIBS="\$(TOP)/src/gallium/auxiliary/pipe-loader/libpipe_loader.a"
+    GALLIUM_PIPE_LOADER_LIBS="$GALLIUM_PIPE_LOADER_LIBS \$(TOP)/src/gallium/winsys/sw/null/libws_null.a"
+
+    if test "x$HAVE_WINSYS_XLIB" = xyes; then
+        GALLIUM_PIPE_LOADER_DEFINES="$GALLIUM_PIPE_LOADER_DEFINES -DHAVE_PIPE_LOADER_XLIB"
+        GALLIUM_PIPE_LOADER_LIBS="$GALLIUM_PIPE_LOADER_LIBS \$(TOP)/src/gallium/winsys/sw/xlib/libws_xlib.a"
+    fi
+
+    if test "x$enable_gallium_drm_loader" = xyes; then
+        GALLIUM_PIPE_LOADER_DEFINES="$GALLIUM_PIPE_LOADER_DEFINES -DHAVE_PIPE_LOADER_DRM"
+    fi
+
+    AC_SUBST([GALLIUM_PIPE_LOADER_DEFINES])
+    AC_SUBST([GALLIUM_PIPE_LOADER_LIBS])
+fi
+
 dnl Tell Automake which drivers to build
 for driver in $GALLIUM_DRIVERS_DIRS; do
     case "x$driver" in
@@ -1990,6 +2009,8 @@ AM_CONDITIONAL(HAVE_IDENTITY_GALLIUM, test x$HAVE_IDENTITY_GALLIUM = xyes)
 AM_CONDITIONAL(HAVE_NOOP_GALLIUM, test x$HAVE_NOOP_GALLIUM = xyes)
 AM_CONDITIONAL(NEED_RADEON_GALLIUM, test x$NEED_RADEON_GALLIUM = xyes)
 AM_CONDITIONAL(USE_R600_LLVM_COMPILER, test x$USE_R600_LLVM_COMPILER = xyes)
+AM_CONDITIONAL(HAVE_LOADER_GALLIUM, test x$enable_gallium_loader = xyes)
+AM_CONDITIONAL(HAVE_DRM_LOADER_GALLIUM, test x$enable_gallium_drm_loader = xyes)
 AC_SUBST([GALLIUM_MAKE_DIRS])
 
 dnl prepend CORE_DIRS to SRC_DIRS
@@ -2005,6 +2026,7 @@ CXXFLAGS="$CXXFLAGS $USER_CXXFLAGS"
 
 dnl Substitute the config
 AC_CONFIG_FILES([configs/autoconf
+		src/gallium/auxiliary/pipe-loader/Makefile
 		src/gallium/drivers/Makefile
 		src/gallium/drivers/r300/Makefile
 		src/gallium/drivers/r600/Makefile