[PULL,v8,147/152] meson: move SDL and SDL-image detection to meson

diff --git a/chardev/meson.build b/chardev/meson.build
index 02f914d6c0..a46a6237be 100644
--- a/chardev/meson.build
+++ b/chardev/meson.build
@@ -36,7 +36,7 @@  softmmu_ss.add(when: ['CONFIG_SPICE', spice], if_true: files('spice.c'))
 
 chardev_modules = {}
 
-if config_host.has_key('CONFIG_BRLAPI') and config_host.has_key('CONFIG_SDL')
+if config_host.has_key('CONFIG_BRLAPI') and sdl.found()
   module_ss = ss.source_set()
   module_ss.add(when: [sdl, brlapi], if_true: files('baum.c'))
   chardev_modules += { 'brlapi': module_ss }
diff --git a/configure b/configure
index 379b6a3446..5448c9624d 100755
--- a/configure
+++ b/configure
@@ -418,8 +418,8 @@  curses=""
 docs=""
 fdt=""
 netmap="no"
-sdl=""
-sdl_image=""
+sdl="auto"
+sdl_image="auto"
 virtfs=""
 mpath=""
 vnc="yes"
@@ -1133,13 +1133,13 @@  for opt do
     # configure to be used by RPM and similar macros that set
     # lots of directory switches by default.
   ;;
-  --disable-sdl) sdl="no"
+  --disable-sdl) sdl="disabled"
   ;;
-  --enable-sdl) sdl="yes"
+  --enable-sdl) sdl="enabled"
   ;;
-  --disable-sdl-image) sdl_image="no"
+  --disable-sdl-image) sdl_image="disabled"
   ;;
-  --enable-sdl-image) sdl_image="yes"
+  --enable-sdl-image) sdl_image="enabled"
   ;;
   --disable-qom-cast-debug) qom_cast_debug="no"
   ;;
@@ -2431,7 +2431,7 @@  if test "$cocoa" = "yes"; then
         error_exit "Cocoa and GTK UIs cannot both be enabled at once"
     fi
     gtk=no
-    sdl=no
+    sdl=disabled
 fi
 
 # Some versions of Mac OS X incorrectly define SIZE_MAX
@@ -3330,125 +3330,6 @@  if test "$vte" != "no"; then
     fi
 fi
 
-##########################################
-# SDL probe
-
-# Look for sdl configuration program (pkg-config or sdl2-config).  Try
-# sdl2-config even without cross prefix, and favour pkg-config over sdl2-config.
-
-sdl_probe ()
-{
-  if $pkg_config sdl2 --exists; then
-    sdlconfig="$pkg_config sdl2"
-    sdlversion=$($sdlconfig --modversion 2>/dev/null)
-  elif has "$sdl2_config"; then
-    sdlconfig="$sdl2_config"
-    sdlversion=$($sdlconfig --version)
-  else
-    if test "$sdl" = "yes" ; then
-      feature_not_found "sdl" "Install SDL2-devel"
-    fi
-    sdl=no
-    # no need to do the rest
-    return
-  fi
-  if test -n "$cross_prefix" && test "$(basename "$sdlconfig")" = sdl2-config; then
-    echo warning: using "\"$sdlconfig\"" to detect cross-compiled sdl >&2
-  fi
-
-  cat > $TMPC << EOF
-#include <SDL.h>
-#undef main /* We don't want SDL to override our main() */
-int main( void ) { return SDL_Init (SDL_INIT_VIDEO); }
-EOF
-  sdl_cflags=$($sdlconfig --cflags 2>/dev/null)
-  sdl_cflags="$sdl_cflags -Wno-undef"  # workaround 2.0.8 bug
-  if test "$static" = "yes" ; then
-    if $pkg_config sdl2 --exists; then
-      sdl_libs=$($pkg_config sdl2 --static --libs 2>/dev/null)
-    else
-      sdl_libs=$($sdlconfig --static-libs 2>/dev/null)
-    fi
-  else
-    sdl_libs=$($sdlconfig --libs 2>/dev/null)
-  fi
-  if compile_prog "$sdl_cflags" "$sdl_libs" ; then
-    sdl=yes
-
-    # static link with sdl ? (note: sdl.pc's --static --libs is broken)
-    if test "$sdl" = "yes" && test "$static" = "yes" ; then
-      if test $? = 0 && echo $sdl_libs | grep -- -laa > /dev/null; then
-         sdl_libs="$sdl_libs $(aalib-config --static-libs 2>/dev/null)"
-         sdl_cflags="$sdl_cflags $(aalib-config --cflags 2>/dev/null)"
-      fi
-      if compile_prog "$sdl_cflags" "$sdl_libs" ; then
-	:
-      else
-        sdl=no
-      fi
-    fi # static link
-  else # sdl not found
-    if test "$sdl" = "yes" ; then
-      feature_not_found "sdl" "Install SDL2 devel"
-    fi
-    sdl=no
-  fi # sdl compile test
-}
-
-sdl_image_probe ()
-{
-    if test "$sdl_image" != "no" ; then
-        if $pkg_config SDL2_image --exists; then
-            if test "$static" = "yes"; then
-                sdl_image_libs=$($pkg_config SDL2_image --libs --static 2>/dev/null)
-            else
-                sdl_image_libs=$($pkg_config SDL2_image --libs 2>/dev/null)
-            fi
-            sdl_image_cflags=$($pkg_config SDL2_image --cflags 2>/dev/null)
-            sdl_image=yes
-
-            sdl_cflags="$sdl_cflags $sdl_image_cflags"
-            sdl_libs="$sdl_libs $sdl_image_libs"
-        else
-            if test "$sdl_image" = "yes" ; then
-                feature_not_found "sdl_image" "Install SDL Image devel"
-            else
-                sdl_image=no
-            fi
-        fi
-    fi
-}
-
-if test "$sdl" != "no" ; then
-  sdl_probe
-fi
-
-if test "$sdl" = "yes" ; then
-  sdl_image_probe
-else
-  if test "$sdl_image" = "yes"; then
-    echo "warning: SDL Image requested, but SDL is not available, disabling"
-  fi
-  sdl_image=no
-fi
-
-if test "$sdl" = "yes" ; then
-  cat > $TMPC <<EOF
-#include <SDL.h>
-#if defined(SDL_VIDEO_DRIVER_X11)
-#include <X11/XKBlib.h>
-#else
-#error No x11 support
-#endif
-int main(void) { return 0; }
-EOF
-  if compile_prog "$sdl_cflags $x11_cflags" "$sdl_libs $x11_libs" ; then
-    need_x11=yes
-    sdl_cflags="$sdl_cflags $x11_cflags"
-    sdl_libs="$sdl_libs $x11_libs"
-  fi
-fi
-
 ##########################################
 # RDMA needs OpenFabrics libraries
 if test "$rdma" != "no" ; then
@@ -7050,14 +6931,6 @@  if test "$have_x11" = "yes" && test "$need_x11" = "yes"; then
   echo "X11_CFLAGS=$x11_cflags" >> $config_host_mak
   echo "X11_LIBS=$x11_libs" >> $config_host_mak
 fi
-if test "$sdl" = "yes" ; then
-  echo "CONFIG_SDL=m" >> $config_host_mak
-  echo "SDL_CFLAGS=$sdl_cflags" >> $config_host_mak
-  echo "SDL_LIBS=$sdl_libs" >> $config_host_mak
-  if test "$sdl_image" = "yes" ; then
-      echo "CONFIG_SDL_IMAGE=y" >> $config_host_mak
-  fi
-fi
 if test "$cocoa" = "yes" ; then
   echo "CONFIG_COCOA=y" >> $config_host_mak
 fi
@@ -8449,6 +8322,7 @@  NINJA=$PWD/ninjatool $meson setup \
         -Dstrip=$(if test "$strip_opt" = yes; then echo true; else echo false; fi) \
         -Db_pie=$(if test "$pie" = yes; then echo true; else echo false; fi) \
         -Db_coverage=$(if test "$gcov" = yes; then echo true; else echo false; fi) \
+	-Dsdl=$sdl -Dsdl_image=$sdl_image \
         $cross_arg \
         "$PWD" "$source_path"
 
diff --git a/meson.build b/meson.build
index 0b03726ad3..f0374e8508 100644
--- a/meson.build
+++ b/meson.build
@@ -11,6 +11,7 @@  cc = meson.get_compiler('c')
 config_host = keyval.load(meson.current_build_dir() / 'config-host.mak')
 config_all_disas = keyval.load(meson.current_build_dir() / 'config-all-disas.mak')
 enable_modules = 'CONFIG_MODULES' in config_host
+enable_static = 'CONFIG_STATIC' in config_host
 build_docs = 'BUILD_DOCS' in config_host
 config_host_data = configuration_data()
 genh = []
@@ -218,13 +219,24 @@  brlapi = not_found
 if 'CONFIG_BRLAPI' in config_host
   brlapi = declare_dependency(link_args: config_host['BRLAPI_LIBS'].split())
 endif
-sdlwindows = false
-sdl = not_found
-if 'CONFIG_SDL' in config_host
-  sdl = declare_dependency(compile_args: config_host['SDL_CFLAGS'].split(),
-                           link_args: config_host['SDL_LIBS'].split())
-  sdlwindows = config_host['SDL_LIBS'].contains('-mwindows')
+
+sdl = dependency('sdl2', required: get_option('sdl'), static: enable_static,
+                 include_type: 'system')
+sdl_image = not_found
+if sdl.found()
+  # work around 2.0.8 bug
+  sdl = declare_dependency(compile_args: '-Wno-undef',
+                           dependencies: sdl)
+  sdl_image = dependency('sdl-image', required: get_option('sdl_image'),
+                         static: enable_static)
+else
+  if get_option('sdl_image').enabled()
+    error('sdl-image required, but SDL was @0@',
+          get_option('sdl').disabled() ? 'disabled' : 'not found')
+  endif
+  sdl_image = not_found
 endif
+
 rbd = not_found
 if 'CONFIG_RBD' in config_host
   rbd = declare_dependency(link_args: config_host['RBD_LIBS'].split())
@@ -363,6 +375,8 @@  endif
 
 # Create config-host.h
 
+config_host_data.set('CONFIG_SDL', sdl.found())
+config_host_data.set('CONFIG_SDL_IMAGE', sdl_image.found())
 config_host_data.set('QEMU_VERSION', '"@0@"'.format(meson.project_version()))
 config_host_data.set('QEMU_VERSION_MAJOR', meson.project_version().split('.')[0])
 config_host_data.set('QEMU_VERSION_MINOR', meson.project_version().split('.')[1])
@@ -963,7 +977,7 @@  foreach target : target_dirs
       'sources': files('softmmu/main.c'),
       'dependencies': []
     }]
-    if sdlwindows
+    if targetos == 'windows' and (sdl.found() or gtk.found())
       execs += [{
         'name': 'qemu-system-' + target_name + 'w',
         'gui': true,
@@ -1239,8 +1253,8 @@  if targetos == 'darwin'
   summary_info += {'Cocoa support': config_host.has_key('CONFIG_COCOA')}
 endif
 # TODO: add back version
-summary_info += {'SDL support':       config_host.has_key('CONFIG_SDL')}
-summary_info += {'SDL image support': config_host.has_key('CONFIG_SDL_IMAGE')}
+summary_info += {'SDL support':       sdl.found()}
+summary_info += {'SDL image support': sdl_image.found()}
 # TODO: add back version
 summary_info += {'GTK support':       config_host.has_key('CONFIG_GTK')}
 summary_info += {'GTK GL support':    config_host.has_key('CONFIG_GTK_GL')}
diff --git a/meson_options.txt b/meson_options.txt
new file mode 100644
index 0000000000..e548211f34
--- /dev/null
+++ b/meson_options.txt
@@ -0,0 +1,2 @@ 
+option('sdl', type : 'feature', value : 'auto')
+option('sdl_image', type : 'feature', value : 'auto')
diff --git a/softmmu/main.c b/softmmu/main.c
index 7adc530c73..639c67ff48 100644
--- a/softmmu/main.c
+++ b/softmmu/main.c
@@ -29,6 +29,7 @@ 
 #ifdef CONFIG_SDL
 #if defined(__APPLE__) || defined(main)
 #include <SDL.h>
+static int qemu_main(int argc, char **argv, char **envp);
 int main(int argc, char **argv)
 {
     return qemu_main(argc, argv, NULL);
diff --git a/ui/meson.build b/ui/meson.build
index 66282c398d..daec6c405e 100644
--- a/ui/meson.build
+++ b/ui/meson.build
@@ -55,11 +55,11 @@  if config_host.has_key('CONFIG_GTK') and config_host.has_key('CONFIG_VTE')
   ui_modules += {'gtk' : gtk_ss}
 endif
 
-if config_host.has_key('CONFIG_SDL')
+if sdl.found()
   softmmu_ss.add(when: 'CONFIG_WIN32', if_true: files('win32-kbd-hook.c'))
 
   sdl_ss = ss.source_set()
-  sdl_ss.add(pixman, glib, files(
+  sdl_ss.add(sdl, sdl_image, pixman, glib, files(
     'sdl2-2d.c',
     'sdl2-input.c',
     'sdl2.c',