android: ijksdl: set surface to NULL when reset/release

ijkmedia/ijkplayer/android/ijkplayer_android.c

@@ -51,16 +51,17 @@ IjkMediaPlayer *ijkmp_android_create(int(*msg_loop)(void*))
 
 void ijkmp_android_set_surface_l(JNIEnv *env, IjkMediaPlayer *mp, jobject android_surface)
 {
-    assert(mp);
-    assert(mp->ffplayer);
-    assert(mp->ffplayer->vout);
+    if (!mp || !mp->ffplayer || !mp->ffplayer->vout)
+        return;
 
     SDL_VoutAndroid_SetAndroidSurface(env, mp->ffplayer->vout, android_surface);
 }
 
 void ijkmp_android_set_surface(JNIEnv *env, IjkMediaPlayer *mp, jobject android_surface)
 {
-    assert(mp);
+    if (!mp)
+        return;
+
     MPTRACE("ijkmp_set_android_surface(surface=%p)", (void*)android_surface);
     pthread_mutex_lock(&mp->mutex);
     ijkmp_android_set_surface_l(env, mp, android_surface);

ijkmedia/ijkplayer/android/ijkplayer_jni.c

@@ -242,6 +242,7 @@ IjkMediaPlayer_release(JNIEnv *env, jobject thiz)
         return;
 
     // explicit shutdown mp, in case it is not the last mp-ref here
+    ijkmp_android_set_surface(env, mp, NULL);
     ijkmp_shutdown(mp);
     jni_set_media_player(env, thiz, NULL);
 
@@ -255,6 +256,7 @@ IjkMediaPlayer_reset(JNIEnv *env, jobject thiz)
     IjkMediaPlayer *mp = jni_get_media_player(env, thiz);
     JNI_CHECK_GOTO(mp, env, NULL, "mpjni: reset: null mp", LABEL_RETURN);
 
+    ijkmp_android_set_surface(env, mp, NULL);
     ijkmp_reset(mp);
 
     LABEL_RETURN:

ijkmedia/ijksdl/android/ijksdl_vout_android_surface.c

@@ -35,13 +35,11 @@ SDL_Vout *SDL_VoutAndroid_CreateForAndroidSurface()
 
 void SDL_VoutAndroid_SetAndroidSurface(JNIEnv *env, SDL_Vout *vout, jobject android_surface)
 {
-    if (!android_surface)
-        return;
-
-    ANativeWindow *native_window = ANativeWindow_fromSurface(env, android_surface);
-    if (!native_window)
-        return;
+    ANativeWindow *native_window = NULL;
+    if (android_surface)
+        native_window = ANativeWindow_fromSurface(env, android_surface);
 
     SDL_VoutAndroid_SetNativeWindow(vout, native_window);
-    ANativeWindow_release(native_window);
+    if (native_window)
+        ANativeWindow_release(native_window);
 }