Add FDFromFence request

This lets DRI clients convert a fence back into a local object.

Signed-off-by: Keith Packard <keithp@keithp.com>

2 files changed, 61 insertions, 1 deletions

diff --git a/dri3proto.h b/dri3proto.h
index 02ea929..ceddee8 100644
--- a/dri3proto.h
+++ b/dri3proto.h
@@ -35,8 +35,9 @@
 #define X_DRI3PixmapFromBuffer          2
 #define X_DRI3BufferFromPixmap          3
 #define X_DRI3FenceFromFD               4
+#define X_DRI3FDFromFence               5
 
-#define DRI3NumberRequests		5
+#define DRI3NumberRequests		6
 
 typedef struct {
     CARD8   reqType;
@@ -138,4 +139,29 @@ typedef struct {
 
 #define sz_xDRI3FenceFromFDReq  16
 
+typedef struct {
+    CARD8   reqType;
+    CARD8   dri3ReqType;
+    CARD16  length B16;
+    CARD32  drawable B32;
+    CARD32  fence B32;
+} xDRI3FDFromFenceReq;
+
+#define sz_xDRI3FDFromFenceReq  12
+
+typedef struct {
+    BYTE    type;   /* X_Reply */
+    CARD8   nfd;    /* Number of file descriptors returned (1) */
+    CARD16  sequenceNumber B16;
+    CARD32  length B32;
+    CARD32  pad08 B32;
+    CARD32  pad12 B32;
+    CARD32  pad16 B32;
+    CARD32  pad20 B32;
+    CARD32  pad24 B32;
+    CARD32  pad28 B32;
+} xDRI3FDFromFenceReply;
+
+#define sz_xDRI3FDFromFenceReply   32
+
 #endif
diff --git a/dri3proto.txt b/dri3proto.txt
index fbc0fed..3f516f7 100644
--- a/dri3proto.txt
+++ b/dri3proto.txt
@@ -182,6 +182,23 @@ The name of this extension is "DRI3"
 	Details about the mechanism used with this file descriptor are
 	outside the scope of the DRI3 extension.
 
+┌───
+    DRI3FDFromFence
+	drawable: DRAWABLE
+	fence: FENCE
+      ▶
+	fd: FD
+└───
+	Errors: IDchoice, Drawable, Match
+
+	Given a Sync extension Fence that provides the regular Sync
+	extension semantics, returns a file descriptor that provides a
+	device-specific mechanism to manipulate the fence directly.
+	Details about the mechanism used with this file descriptor are
+	outside the scope of the DRI3 extension. 'drawable' must be
+	associated with a direct rendering device that 'fence' can
+	work with, otherwise a Match error results.
+
 
 			     ❄ ❄ ❄  ❄  ❄ ❄ ❄ 
 
@@ -337,6 +354,23 @@ A.2 Protocol Requests
 	0	FD			fence fd
 └───
 
+┌───
+    DRI3FDFromFence
+	1	CARD8			major opcode
+	1	5			DRI3 opcode
+	2	3			length
+	4	Drawable		drawable
+	4	Fence			fence
+      ▶	
+	1	1			Reply
+        1	1			nfd
+	2	CARD16			sequence number
+	4	0			reply length
+	24				unused
+
+	0	FD			fence fd
+└───
+
 A.3 Protocol Events
 
 The DRI3 extension defines no events.