From a933259daa98615ad7473c53623a96f612e9a311 Mon Sep 17 00:00:00 2001
From: Chia-I Wu <olvaffe@gmail.com>
Date: Wed, 27 Jan 2010 23:55:58 +0800
Subject: [PATCH] egl: Use a boolean to indicate whether a display is
 initialized.

The driver pointer of the display was used to decide whether a display
is initialized.  Use a boolean for that purpose allows accessing the
driver of an uninitialized display.
---
 src/egl/main/eglapi.c     | 35 +++++++++++++++++++----------------
 src/egl/main/egldisplay.h |  1 +
 2 files changed, 20 insertions(+), 16 deletions(-)

diff --git a/src/egl/main/eglapi.c b/src/egl/main/eglapi.c
index 90828bd3e90..2c26dfada8e 100644
--- a/src/egl/main/eglapi.c
+++ b/src/egl/main/eglapi.c
@@ -94,19 +94,20 @@ EGLBoolean EGLAPIENTRY
 eglInitialize(EGLDisplay dpy, EGLint *major, EGLint *minor)
 {
    _EGLDisplay *disp = _eglLookupDisplay(dpy);
-   _EGLDriver *drv;
    EGLint major_int, minor_int;
 
    if (!disp)
       return _eglError(EGL_BAD_DISPLAY, __FUNCTION__);
 
-   drv = disp->Driver;
-   if (!drv) {
-      _eglPreloadDrivers();
+   if (!disp->Initialized) {
+      _EGLDriver *drv = disp->Driver;
 
-      drv = _eglMatchDriver(disp);
-      if (!drv)
-         return _eglError(EGL_NOT_INITIALIZED, __FUNCTION__);
+      if (!drv) {
+         _eglPreloadDrivers();
+         drv = _eglMatchDriver(disp);
+         if (!drv)
+            return _eglError(EGL_NOT_INITIALIZED, __FUNCTION__);
+      }
 
       /* Initialize the particular display now */
       if (!drv->API.Initialize(drv, disp, &major_int, &minor_int))
@@ -121,6 +122,7 @@ eglInitialize(EGLDisplay dpy, EGLint *major, EGLint *minor)
       disp->ClientAPIsMask &= _EGL_API_ALL_BITS;
 
       disp->Driver = drv;
+      disp->Initialized = EGL_TRUE;
    } else {
       major_int = disp->APImajor;
       minor_int = disp->APIminor;
@@ -140,15 +142,16 @@ EGLBoolean EGLAPIENTRY
 eglTerminate(EGLDisplay dpy)
 {
    _EGLDisplay *disp = _eglLookupDisplay(dpy);
-   _EGLDriver *drv;
 
    if (!disp)
       return _eglError(EGL_BAD_DISPLAY, __FUNCTION__);
 
-   drv = disp->Driver;
-   if (drv) {
+   if (disp->Initialized) {
+      _EGLDriver *drv = disp->Driver;
+
       drv->API.Terminate(drv, disp);
-      disp->Driver = NULL;
+      /* do not reset disp->Driver */
+      disp->Initialized = EGL_FALSE;
    }
 
    return EGL_TRUE;
@@ -165,7 +168,7 @@ _eglCheckDisplay(_EGLDisplay *disp, const char *msg)
       _eglError(EGL_BAD_DISPLAY, msg);
       return NULL;
    }
-   if (!disp->Driver) {
+   if (!disp->Initialized) {
       _eglError(EGL_NOT_INITIALIZED, msg);
       return NULL;
    }
@@ -572,8 +575,8 @@ eglWaitClient(void)
 
    /* a valid current context implies an initialized current display */
    disp = ctx->Resource.Display;
+   assert(disp->Initialized);
    drv = disp->Driver;
-   assert(drv);
 
    return drv->API.WaitClient(drv, disp, ctx);
 }
@@ -616,8 +619,8 @@ eglWaitNative(EGLint engine)
 
    /* a valid current context implies an initialized current display */
    disp = ctx->Resource.Display;
+   assert(disp->Initialized);
    drv = disp->Driver;
-   assert(drv);
 
    return drv->API.WaitNative(drv, disp, engine);
 }
@@ -991,8 +994,8 @@ eglReleaseThread(void)
          if (ctx) {
             _EGLDisplay *disp = ctx->Resource.Display;
             _EGLDriver *drv = disp->Driver;
-            /* what if drv is not avaialbe? */
-            if (drv)
+            /* what if display is not initialized? */
+            if (disp->Initialized)
                (void) drv->API.MakeCurrent(drv, disp, NULL, NULL, NULL);
          }
       }
diff --git a/src/egl/main/egldisplay.h b/src/egl/main/egldisplay.h
index 8f74ad23a87..4aea10c3eb3 100644
--- a/src/egl/main/egldisplay.h
+++ b/src/egl/main/egldisplay.h
@@ -49,6 +49,7 @@ struct _egl_display
 
    EGLNativeDisplayType NativeDisplay;
 
+   EGLBoolean Initialized; /**< True if the display is initialized */
    _EGLDriver *Driver;
    void *DriverData; /* private to driver */
 
-- 
2.30.2