sync code with last improvements from OpenBSD

xserver/miext/sync/misyncfd.h

@@ -0,0 +1,45 @@
+/*
+ * Copyright © 2013 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#ifndef _MISYNCFD_H_
+#define _MISYNCFD_H_
+
+typedef int (*SyncScreenCreateFenceFromFdFunc) (ScreenPtr screen,
+                                                SyncFence *fence,
+                                                int fd,
+                                                Bool initially_triggered);
+
+typedef int (*SyncScreenGetFenceFdFunc) (ScreenPtr screen,
+                                      SyncFence *fence);
+
+#define SYNC_FD_SCREEN_FUNCS_VERSION    1
+
+typedef struct _syncFdScreenFuncs {
+    int                                 version;
+    SyncScreenCreateFenceFromFdFunc     CreateFenceFromFd;
+    SyncScreenGetFenceFdFunc            GetFenceFd;
+} SyncFdScreenFuncsRec, *SyncFdScreenFuncsPtr;
+
+extern _X_EXPORT Bool miSyncFdScreenInit(ScreenPtr pScreen,
+                                         const SyncFdScreenFuncsRec *funcs);
+
+#endif /* _MISYNCFD_H_ */