[Mesa-dev] [PATCH 1/3] egl: Add eglQuerySurface surface type check for EGL_LARGEST_PBUFFER attrib

[Frank Binns]

Calling eglQuerySurface on a window or pixmap with the EGL_LARGEST_PBUFFER
attribute resulted in the contents of the 'value' parameter being modified.
This is the wrong behaviour according to the EGL spec, which states:

    "Querying EGL_LARGEST_PBUFFER for a pbuffer surface returns the
     same attribute value specified when the surface was created with
     eglCreatePbufferSurface. For a window or pixmap surface, the
     contents of value are not modified."

Avoid this from happening by checking that the surface type is EGL_PBUFFER_BIT
before modifying the contents of the parameter.

Signed-off-by: Frank Binns <frank.binns at imgtec.com>
---
 src/egl/main/eglsurface.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/egl/main/eglsurface.c b/src/egl/main/eglsurface.c
index 541353f..4fa43f3 100644
--- a/src/egl/main/eglsurface.c
+++ b/src/egl/main/eglsurface.c
@@ -326,7 +326,8 @@ _eglQuerySurface(_EGLDriver *drv, _EGLDisplay *dpy, _EGLSurface *surface,
       *value = surface->Config->ConfigID;
       break;
    case EGL_LARGEST_PBUFFER:
-      *value = surface->LargestPbuffer;
+      if (surface->Type == EGL_PBUFFER_BIT)
+         *value = surface->LargestPbuffer;
       break;
    case EGL_TEXTURE_FORMAT:
       /* texture attributes: only for pbuffers, no error otherwise */
-- 
1.8.5.4.gfdaaaa2