egl: Check if API is supported when using eglBindAPI.

According to the EGL specifications before binding an API
we must check whether it's supported first. If not eglBindAPI
should return EGL_FALSE and generate a EGL_BAD_PARAMETER error.

Signed-off-by: Plamena Manolova <plamena.manolova@intel.com>
Reviewed-by: Brian Paul <brianp@vmware.com>

src/egl/main/eglapi.c

@@ -1196,6 +1196,61 @@ eglGetError(void)
 }
 
 
+static bool
+_eglDisplaySupportsApi(_EGLDisplay *dpy, EGLenum api)
+{
+   if (!dpy->Initialized) {
+      return false;
+   }
+
+   switch (api) {
+   case EGL_OPENGL_API:
+      return !!(dpy->ClientAPIs & EGL_OPENGL_BIT);
+   case EGL_OPENGL_ES_API:
+      return dpy->ClientAPIs & EGL_OPENGL_ES_BIT ||
+             dpy->ClientAPIs & EGL_OPENGL_ES2_BIT ||
+             dpy->ClientAPIs & EGL_OPENGL_ES3_BIT_KHR;
+   case EGL_OPENVG_API:
+      return !!(dpy->ClientAPIs & EGL_OPENVG_BIT);
+   }
+
+   return false;
+}
+
+
+/**
+ * Return true if a client API enum is recognized.
+ */
+static bool
+_eglIsApiValid(EGLenum api)
+{
+   _EGLDisplay *dpy = _eglGlobal.DisplayList;
+   _EGLThreadInfo *current_thread = _eglGetCurrentThread();
+
+   if (api != EGL_OPENGL_API && api != EGL_OPENGL_ES_API &&
+       api != EGL_OPENVG_API) {
+      return false;
+   }
+
+   while (dpy) {
+      _EGLThreadInfo *thread = dpy->ThreadList;
+
+      while (thread) {
+         if (thread == current_thread) {
+            if (_eglDisplaySupportsApi(dpy, api))
+               return true;
+         }
+
+         thread = thread->Next;
+      }
+
+      dpy = dpy->Next;
+   }
+
+   return false;
+}
+
+
 /**
  ** EGL 1.2
  **/
@@ -1211,6 +1266,16 @@ eglGetError(void)
  *  eglWaitNative()
  * See section 3.7 "Rendering Context" in the EGL specification for details.
  */
+
+ /**
+  * Section 3.7 (Rendering Contexts) of the EGL 1.5 spec says:
+  *
+  * "api must specify one of the supported client APIs, either
+  * EGL_OPENGL_API, EGL_OPENGL_ES_API, or EGL_OPENVG_API... If api
+  * is not one of the values specified above, or if the client API
+  * specified by api is not supported by the implementation, an
+  * EGL_BAD_PARAMETER error is generated."
+  */
 EGLBoolean EGLAPIENTRY
 eglBindAPI(EGLenum api)
 {

src/egl/main/eglcurrent.h

@@ -56,6 +56,7 @@ extern "C" {
  */
 struct _egl_thread_info
 {
+   _EGLThreadInfo *Next; /* used to link threads */
    EGLint LastError;
    _EGLContext *CurrentContexts[_EGL_API_NUM_APIS];
    /* use index for fast access to current context */
@@ -63,16 +64,6 @@ struct _egl_thread_info
 };
 
 
-/**
- * Return true if a client API enum is recognized.
- */
-static inline EGLBoolean
-_eglIsApiValid(EGLenum api)
-{
-   return (api >= _EGL_API_FIRST_API && api <= _EGL_API_LAST_API);
-}
-
-
 /**
  * Convert a client API enum to an index, for use by thread info.
  * The client API enum is assumed to be valid.

src/egl/main/egldisplay.c

@@ -240,6 +240,7 @@ _EGLDisplay *
 _eglFindDisplay(_EGLPlatformType plat, void *plat_dpy)
 {
    _EGLDisplay *dpy;
+   _EGLThreadInfo *thread = _eglGetCurrentThread();
 
    if (plat == _EGL_INVALID_PLATFORM)
       return NULL;
@@ -265,9 +266,13 @@ _eglFindDisplay(_EGLPlatformType plat, void *plat_dpy)
          /* add to the display list */ 
          dpy->Next = _eglGlobal.DisplayList;
          _eglGlobal.DisplayList = dpy;
+         dpy->ThreadList = NULL;
       }
    }
 
+   thread->Next = dpy->ThreadList;
+   dpy->ThreadList = thread;
+
    mtx_unlock(_eglGlobal.Mutex);
 
    return dpy;

src/egl/main/egldisplay.h

@@ -140,6 +140,7 @@ struct _egl_display
    _EGLPlatformType Platform; /**< The type of the platform display */
    void *PlatformDisplay;     /**< A pointer to the platform display */
 
+   _EGLThreadInfo *ThreadList;/**< A pointer to the thread the display was created form */
    _EGLDriver *Driver;        /**< Matched driver of the display */
    EGLBoolean Initialized;    /**< True if the display is initialized */