egl/main: Stop using EGLNative types internally

Internally, much of the EGL code uses EGLNativeDisplayType,
EGLNativeWindowType, and EGLPixmapType. However, the EGLNative type
often does not match the variable's actual type.

The concept of EGLNative types are a bad match for Linux, as explained
below. And the EGL platform extensions don't use EGLNative types at all.
Those extensions attempt to solve cross-platform issues by moving the
EGL API away from the EGLNative types.

The core of the problem is that eglplatform.h can define each EGLNative
type once only, but Linux supports multiple EGL platforms.

To work around the problem, Mesa's eglplatform.h contains multiple
definitions of each EGLNative type, selected by feature macros. Mesa
expects EGL clients to set the feature macro approrpiately. But the
feature macros don't work when a single codebase must be built with
support for multiple EGL platforms, *such as Mesa itself*.

When building libEGL, autotools chooses the EGLNative typedefs based on
the first element of '--with-egl-platforms'. For example,
'--with-egl-platforms=x11,drm,wayland' defines the following:

    typedef Display* EGLNativeDisplayType;
    typedef Window   EGLNativeWindowType;
    typedef Pixmap   EGLNativePixmapType;

Clearly, this doesn't work well for Wayland and GBM.  Mesa works around
the problem by casting the EGLNative types to different things in
different files.

For sanity's sake, and to prepare for the EGL platform extensions, this
patch removes from egl/main and egl/dri2 all internal use of the
EGLNative types. It replaces them with 'void*' and checks each explicit
cast with a static assertion. Also, the patch touches egl_gallium the
minimal amount to keep it compatible with eglapi.h.

Signed-off-by: Chad Versace <[email protected]>

4 files changed, 32 insertions, 11 deletions

diff --git a/src/egl/main/eglapi.c b/src/egl/main/eglapi.c
index 950c447de9d..836714ce244 100644
--- a/src/egl/main/eglapi.c
+++ b/src/egl/main/eglapi.c
@@ -296,8 +296,15 @@ _eglUnlockDisplay(_EGLDisplay *dpy)
 EGLDisplay EGLAPIENTRY
 eglGetDisplay(EGLNativeDisplayType nativeDisplay)
 {
-   _EGLPlatformType plat = _eglGetNativePlatform(nativeDisplay);
-   _EGLDisplay *dpy = _eglFindDisplay(plat, (void *) nativeDisplay);
+   _EGLPlatformType plat;
+   _EGLDisplay *dpy;
+   void *native_display_ptr;
+
+   STATIC_ASSERT(sizeof(void*) == sizeof(nativeDisplay));
+   native_display_ptr = (void*) nativeDisplay;
+
+   plat = _eglGetNativePlatform(native_display_ptr);
+   dpy = _eglFindDisplay(plat, native_display_ptr);
    return _eglGetDisplayHandle(dpy);
 }
 
@@ -529,12 +536,17 @@ eglCreateWindowSurface(EGLDisplay dpy, EGLConfig config,
    _EGLDriver *drv;
    _EGLSurface *surf;
    EGLSurface ret;
+   void *native_window_ptr;
+
+   STATIC_ASSERT(sizeof(void*) == sizeof(window));
+   native_window_ptr = (void*) window;
 
    _EGL_CHECK_CONFIG(disp, conf, EGL_NO_SURFACE, drv);
    if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay))
       RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_WINDOW, EGL_NO_SURFACE);
 
-   surf = drv->API.CreateWindowSurface(drv, disp, conf, window, attrib_list);
+   surf = drv->API.CreateWindowSurface(drv, disp, conf, native_window_ptr,
+                                       attrib_list);
    ret = (surf) ? _eglLinkSurface(surf) : EGL_NO_SURFACE;
 
    RETURN_EGL_EVAL(disp, ret);
@@ -550,12 +562,17 @@ eglCreatePixmapSurface(EGLDisplay dpy, EGLConfig config,
    _EGLDriver *drv;
    _EGLSurface *surf;
    EGLSurface ret;
+   void *native_pixmap_ptr;
+
+   STATIC_ASSERT(sizeof(void*) == sizeof(pixmap));
+   native_pixmap_ptr = (void*) pixmap;
 
    _EGL_CHECK_CONFIG(disp, conf, EGL_NO_SURFACE, drv);
    if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay))
       RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_PIXMAP, EGL_NO_SURFACE);
 
-   surf = drv->API.CreatePixmapSurface(drv, disp, conf, pixmap, attrib_list);
+   surf = drv->API.CreatePixmapSurface(drv, disp, conf, native_pixmap_ptr,
+                                       attrib_list);
    ret = (surf) ? _eglLinkSurface(surf) : EGL_NO_SURFACE;
 
    RETURN_EGL_EVAL(disp, ret);
@@ -740,11 +757,15 @@ eglCopyBuffers(EGLDisplay dpy, EGLSurface surface, EGLNativePixmapType target)
    _EGLSurface *surf = _eglLookupSurface(surface, disp);
    _EGLDriver *drv;
    EGLBoolean ret;
+   void *native_pixmap_ptr;
+
+   STATIC_ASSERT(sizeof(void*) == sizeof(target));
+   native_pixmap_ptr = (void*) target;
 
    _EGL_CHECK_SURFACE(disp, surf, EGL_FALSE, drv);
    if (disp->Platform != _eglGetNativePlatform(disp->PlatformDisplay))
       RETURN_EGL_ERROR(disp, EGL_BAD_NATIVE_PIXMAP, EGL_FALSE);
-   ret = drv->API.CopyBuffers(drv, disp, surf, target);
+   ret = drv->API.CopyBuffers(drv, disp, surf, native_pixmap_ptr);
 
    RETURN_EGL_EVAL(disp, ret);
 }
diff --git a/src/egl/main/eglapi.h b/src/egl/main/eglapi.h
index 091c09cbfa8..f20ce5b701b 100644
--- a/src/egl/main/eglapi.h
+++ b/src/egl/main/eglapi.h
@@ -58,8 +58,8 @@ typedef EGLBoolean (*MakeCurrent_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurfa
 typedef EGLBoolean (*QueryContext_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLContext *ctx, EGLint attribute, EGLint *value);
 
 /* surface funcs */
-typedef _EGLSurface *(*CreateWindowSurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *config, EGLNativeWindowType window, const EGLint *attrib_list);
-typedef _EGLSurface *(*CreatePixmapSurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *config, EGLNativePixmapType pixmap, const EGLint *attrib_list);
+typedef _EGLSurface *(*CreateWindowSurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *config, void *native_window, const EGLint *attrib_list);
+typedef _EGLSurface *(*CreatePixmapSurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *config, void *native_pixmap, const EGLint *attrib_list);
 typedef _EGLSurface *(*CreatePbufferSurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLConfig *config, const EGLint *attrib_list);
 typedef EGLBoolean (*DestroySurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface);
 typedef EGLBoolean (*QuerySurface_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface, EGLint attribute, EGLint *value);
@@ -68,7 +68,7 @@ typedef EGLBoolean (*BindTexImage_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurf
 typedef EGLBoolean (*ReleaseTexImage_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface, EGLint buffer);
 typedef EGLBoolean (*SwapInterval_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surf, EGLint interval);
 typedef EGLBoolean (*SwapBuffers_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *draw);
-typedef EGLBoolean (*CopyBuffers_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface, EGLNativePixmapType target);
+typedef EGLBoolean (*CopyBuffers_t)(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface, void *native_pixmap_target);
 
 /* misc funcs */
 typedef const char *(*QueryString_t)(_EGLDriver *drv, _EGLDisplay *dpy, EGLint name);
diff --git a/src/egl/main/egldisplay.c b/src/egl/main/egldisplay.c
index bed7663efc5..b43e3ea5d9b 100644
--- a/src/egl/main/egldisplay.c
+++ b/src/egl/main/egldisplay.c
@@ -139,7 +139,7 @@ _eglPointerIsDereferencable(void *p)
  * Try detecting native platform with the help of native display characteristcs.
  */
 static _EGLPlatformType
-_eglNativePlatformDetectNativeDisplay(EGLNativeDisplayType nativeDisplay)
+_eglNativePlatformDetectNativeDisplay(void *nativeDisplay)
 {
 #ifdef HAVE_FBDEV_PLATFORM
    struct stat buf;
@@ -186,7 +186,7 @@ _eglNativePlatformDetectNativeDisplay(EGLNativeDisplayType nativeDisplay)
  * Return the native platform.  It is the platform of the EGL native types.
  */
 _EGLPlatformType
-_eglGetNativePlatform(EGLNativeDisplayType nativeDisplay)
+_eglGetNativePlatform(void *nativeDisplay)
 {
    static _EGLPlatformType native_platform = _EGL_INVALID_PLATFORM;
    char *detection_method = NULL;
diff --git a/src/egl/main/egldisplay.h b/src/egl/main/egldisplay.h
index 0952bc960cf..911a2e9bd67 100644
--- a/src/egl/main/egldisplay.h
+++ b/src/egl/main/egldisplay.h
@@ -162,7 +162,7 @@ struct _egl_display
 
 
 extern _EGLPlatformType
-_eglGetNativePlatform(EGLNativeDisplayType nativeDisplay);
+_eglGetNativePlatform(void *nativeDisplay);
 
 
 extern void