[PULL,11/18] configure, meson: move OpenGL check to meson

diff --git a/configure b/configure
index d704029284..1aefbc2f68 100755
--- a/configure
+++ b/configure
@@ -321,7 +321,6 @@  bsd_user=""
 pkgversion=""
 pie=""
 trace_file="trace"
-opengl="$default_feature"
 coroutine=""
 tls_priority="NORMAL"
 plugins="$default_feature"
@@ -960,10 +959,6 @@  for opt do
   ;;
   --enable-vhost-user-fs) vhost_user_fs="yes"
   ;;
-  --disable-opengl) opengl="no"
-  ;;
-  --enable-opengl) opengl="yes"
-  ;;
   --disable-zlib-test)
   ;;
   --disable-virtio-blk-data-plane|--enable-virtio-blk-data-plane)
@@ -1258,7 +1253,6 @@  cat << EOF
   vhost-kernel    vhost kernel backend support
   vhost-user      vhost-user backend support
   vhost-vdpa      vhost-vdpa kernel backend support
-  opengl          opengl support
   gio             libgio support
 
 NOTE: The object files are built at the place where configure is launched
@@ -2278,34 +2272,6 @@  case "$fdt" in
 esac
 
 ##########################################
-# opengl probe (for sdl2, gtk)
-
-if test "$opengl" != "no" ; then
-  epoxy=no
-  if $pkg_config epoxy; then
-    cat > $TMPC << EOF
-#include <epoxy/egl.h>
-int main(void) { return 0; }
-EOF
-    if compile_prog "" "" ; then
-      epoxy=yes
-    fi
-  fi
-
-  if test "$epoxy" = "yes" ; then
-    opengl_cflags="$($pkg_config --cflags epoxy)"
-    opengl_libs="$($pkg_config --libs epoxy)"
-    opengl=yes
-  else
-    if test "$opengl" = "yes" ; then
-      feature_not_found "opengl" "Please install epoxy with EGL"
-    fi
-    opengl_cflags=""
-    opengl_libs=""
-    opengl=no
-  fi
-fi
-
 # check for usbfs
 have_usbfs=no
 if test "$linux_user" = "yes"; then
@@ -2874,12 +2840,6 @@  if test "$vhost_user_fs" = "yes" ; then
   echo "CONFIG_VHOST_USER_FS=y" >> $config_host_mak
 fi
 
-if test "$opengl" = "yes" ; then
-  echo "CONFIG_OPENGL=y" >> $config_host_mak
-  echo "OPENGL_CFLAGS=$opengl_cflags" >> $config_host_mak
-  echo "OPENGL_LIBS=$opengl_libs" >> $config_host_mak
-fi
-
 # XXX: suppress that
 if [ "$bsd" = "yes" ] ; then
   echo "CONFIG_BSD=y" >> $config_host_mak
diff --git a/meson.build b/meson.build
index 9beca38ebb..83b7347c5f 100644
--- a/meson.build
+++ b/meson.build
@@ -1000,9 +1000,14 @@  if not get_option('coreaudio').auto() or (targetos == 'darwin' and have_system)
 endif
 
 opengl = not_found
-if 'CONFIG_OPENGL' in config_host
-  opengl = declare_dependency(compile_args: config_host['OPENGL_CFLAGS'].split(),
-                              link_args: config_host['OPENGL_LIBS'].split())
+if not get_option('opengl').auto() or have_system or have_vhost_user_gpu
+  epoxy = dependency('epoxy', method: 'pkg-config',
+                      required: get_option('opengl'), kwargs: static_kwargs)
+  if cc.has_header('epoxy/egl.h', dependencies: epoxy)
+    opengl = epoxy
+  elif get_option('opengl').enabled()
+    error('epoxy/egl.h not found')
+  endif
 endif
 gbm = not_found
 if (have_system or have_tools) and (virgl.found() or opengl.found())
@@ -1546,6 +1551,7 @@  config_host_data.set('CONFIG_LINUX_AIO', libaio.found())
 config_host_data.set('CONFIG_LINUX_IO_URING', linux_io_uring.found())
 config_host_data.set('CONFIG_LIBPMEM', libpmem.found())
 config_host_data.set('CONFIG_NUMA', numa.found())
+config_host_data.set('CONFIG_OPENGL', opengl.found())
 config_host_data.set('CONFIG_PROFILER', get_option('profiler'))
 config_host_data.set('CONFIG_RBD', rbd.found())
 config_host_data.set('CONFIG_SDL', sdl.found())
@@ -2093,7 +2099,7 @@  host_kconfig = \
   (have_tpm ? ['CONFIG_TPM=y'] : []) + \
   (spice.found() ? ['CONFIG_SPICE=y'] : []) + \
   (have_ivshmem ? ['CONFIG_IVSHMEM=y'] : []) + \
-  ('CONFIG_OPENGL' in config_host ? ['CONFIG_OPENGL=y'] : []) + \
+  (opengl.found() ? ['CONFIG_OPENGL=y'] : []) + \
   (x11.found() ? ['CONFIG_X11=y'] : []) + \
   ('CONFIG_VHOST_USER' in config_host ? ['CONFIG_VHOST_USER=y'] : []) + \
   ('CONFIG_VHOST_VDPA' in config_host ? ['CONFIG_VHOST_VDPA=y'] : []) + \
@@ -3708,7 +3714,7 @@  summary_info += {'smartcard support': cacard}
 summary_info += {'U2F support':       u2f}
 summary_info += {'libusb':            libusb}
 summary_info += {'usb net redir':     usbredir}
-summary_info += {'OpenGL support':    config_host.has_key('CONFIG_OPENGL')}
+summary_info += {'OpenGL support (epoxy)': opengl}
 summary_info += {'GBM':               gbm}
 summary_info += {'libiscsi support':  libiscsi}
 summary_info += {'libnfs support':    libnfs}
diff --git a/meson_options.txt b/meson_options.txt
index d85734f8e6..dbcf9722bb 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -149,6 +149,8 @@  option('lzo', type : 'feature', value : 'auto',
        description: 'lzo compression support')
 option('rbd', type : 'feature', value : 'auto',
        description: 'Ceph block device driver')
+option('opengl', type : 'feature', value : 'auto',
+       description: 'OpenGL support')
 option('gtk', type : 'feature', value : 'auto',
        description: 'GTK+ user interface')
 option('sdl', type : 'feature', value : 'auto',
diff --git a/scripts/meson-buildoptions.sh b/scripts/meson-buildoptions.sh
index ef0dcd4a77..203f33ae18 100644
--- a/scripts/meson-buildoptions.sh
+++ b/scripts/meson-buildoptions.sh
@@ -91,6 +91,7 @@  meson_options_help() {
   printf "%s\n" '  nettle          nettle cryptography support'
   printf "%s\n" '  numa            libnuma support'
   printf "%s\n" '  nvmm            NVMM acceleration support'
+  printf "%s\n" '  opengl          OpenGL support'
   printf "%s\n" '  oss             OSS sound support'
   printf "%s\n" '  pa              PulseAudio sound support'
   printf "%s\n" '  parallels       parallels image format support'
@@ -271,6 +272,8 @@  _meson_option_parse() {
     --disable-numa) printf "%s" -Dnuma=disabled ;;
     --enable-nvmm) printf "%s" -Dnvmm=enabled ;;
     --disable-nvmm) printf "%s" -Dnvmm=disabled ;;
+    --enable-opengl) printf "%s" -Dopengl=enabled ;;
+    --disable-opengl) printf "%s" -Dopengl=disabled ;;
     --enable-oss) printf "%s" -Doss=enabled ;;
     --disable-oss) printf "%s" -Doss=disabled ;;
     --enable-pa) printf "%s" -Dpa=enabled ;;
diff --git a/ui/meson.build b/ui/meson.build
index 64286ba150..b21d3d1534 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -1,5 +1,6 @@ 
 softmmu_ss.add(pixman)
 specific_ss.add(when: ['CONFIG_SOFTMMU'], if_true: pixman)   # for the include path
+specific_ss.add(when: ['CONFIG_SOFTMMU'], if_true: opengl)   # for the include path
 
 softmmu_ss.add(files(
   'clipboard.c',
@@ -43,7 +44,6 @@  vnc_ss.add(zlib, png, jpeg, gnutls)
 vnc_ss.add(when: sasl, if_true: files('vnc-auth-sasl.c'))
 softmmu_ss.add_all(when: vnc, if_true: vnc_ss)
 softmmu_ss.add(when: vnc, if_false: files('vnc-stubs.c'))
-specific_ss.add(when: ['CONFIG_SOFTMMU'], if_true: opengl)
 
 ui_modules = {}
 
@@ -53,17 +53,18 @@  if curses.found()
   ui_modules += {'curses' : curses_ss}
 endif
 
-if config_host.has_key('CONFIG_OPENGL')
+softmmu_ss.add(opengl)
+if opengl.found()
   opengl_ss = ss.source_set()
   opengl_ss.add(gbm)
-  opengl_ss.add(when: [opengl, pixman, 'CONFIG_OPENGL'],
+  opengl_ss.add(when: [opengl, pixman],
                if_true: files('shader.c', 'console-gl.c', 'egl-helpers.c', 'egl-context.c'))
   ui_modules += {'opengl' : opengl_ss}
 endif
 
-if config_host.has_key('CONFIG_OPENGL') and gbm.found()
+if opengl.found() and gbm.found()
   egl_headless_ss = ss.source_set()
-  egl_headless_ss.add(when: [opengl, gbm, pixman, 'CONFIG_OPENGL'],
+  egl_headless_ss.add(when: [opengl, gbm, pixman],
                       if_true: files('egl-headless.c'))
   ui_modules += {'egl-headless' : egl_headless_ss}
 endif
@@ -98,8 +99,8 @@  if gtk.found()
   gtk_ss = ss.source_set()
   gtk_ss.add(gtk, vte, pixman, files('gtk.c', 'gtk-clipboard.c'))
   gtk_ss.add(when: x11, if_true: files('x_keymap.c'))
-  gtk_ss.add(when: [opengl, 'CONFIG_OPENGL'], if_true: files('gtk-gl-area.c'))
-  gtk_ss.add(when: [x11, opengl, 'CONFIG_OPENGL'], if_true: files('gtk-egl.c'))
+  gtk_ss.add(when: opengl, if_true: files('gtk-gl-area.c'))
+  gtk_ss.add(when: [x11, opengl], if_true: files('gtk-egl.c'))
   ui_modules += {'gtk' : gtk_ss}
 endif
 
@@ -112,7 +113,7 @@  if sdl.found()
     'sdl2-input.c',
     'sdl2.c',
   ))
-  sdl_ss.add(when: [opengl, 'CONFIG_OPENGL'], if_true: files('sdl2-gl.c'))
+  sdl_ss.add(when: opengl, if_true: files('sdl2-gl.c'))
   sdl_ss.add(when: x11, if_true: files('x_keymap.c'))
   ui_modules += {'sdl' : sdl_ss}
 endif