miext: Ensure xshmfence is only called when driver supports it

This provides a place for drivers to insert their own FD-based
SyncFence implementations, and prevents applications from using DRI3
SyncFence creation functions unless the driver has some support for
them.

Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Fredrik Höglund <fredrik@kde.org>

1 files changed, 99 insertions, 0 deletions

diff --git a/miext/sync/misyncfd.c b/miext/sync/misyncfd.c
new file mode 100644
index 000000000..93ff85fa8
--- /dev/null
+++ b/miext/sync/misyncfd.c
@@ -0,0 +1,99 @@
+/*
+ * 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.
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include "scrnintstr.h"
+#include "misync.h"
+#include "misyncstr.h"
+#include "misyncfd.h"
+#include "pixmapstr.h"
+
+static DevPrivateKeyRec syncFdScreenPrivateKey;
+
+typedef struct _SyncFdScreenPrivate {
+    SyncFdScreenFuncsRec        funcs;
+} SyncFdScreenPrivateRec, *SyncFdScreenPrivatePtr;
+
+static inline SyncFdScreenPrivatePtr sync_fd_screen_priv(ScreenPtr pScreen)
+{
+    if (!dixPrivateKeyRegistered(&syncFdScreenPrivateKey))
+        return NULL;
+    return dixLookupPrivate(&pScreen->devPrivates, &syncFdScreenPrivateKey);
+}
+
+int
+miSyncInitFenceFromFD(DrawablePtr pDraw, SyncFence *pFence, int fd, BOOL initially_triggered)
+
+{
+    SyncFdScreenPrivatePtr      priv = sync_fd_screen_priv(pDraw->pScreen);
+
+    if (!priv)
+        return BadMatch;
+
+    return (*priv->funcs.CreateFenceFromFd)(pDraw->pScreen, pFence, fd, initially_triggered);
+}
+
+int
+miSyncFDFromFence(DrawablePtr pDraw, SyncFence *pFence)
+{
+    SyncFdScreenPrivatePtr      priv = sync_fd_screen_priv(pDraw->pScreen);
+
+    if (!priv)
+        return -1;
+
+    return (*priv->funcs.GetFenceFd)(pDraw->pScreen, pFence);
+}
+
+_X_EXPORT Bool miSyncFdScreenInit(ScreenPtr pScreen,
+                                  const SyncFdScreenFuncsRec *funcs)
+{
+    SyncFdScreenPrivatePtr     priv;
+
+    /* Check to see if we've already been initialized */
+    if (sync_fd_screen_priv(pScreen) != NULL)
+        return FALSE;
+
+    if (!miSyncSetup(pScreen))
+        return FALSE;
+    
+    if (!dixPrivateKeyRegistered(&syncFdScreenPrivateKey)) {
+        if (!dixRegisterPrivateKey(&syncFdScreenPrivateKey, PRIVATE_SCREEN, 0))
+            return FALSE;
+    }
+
+    priv = calloc(1, sizeof (SyncFdScreenPrivateRec));
+    if (!priv)
+        return FALSE;
+
+    /* Will require version checks when there are multiple versions
+     * of the funcs structure
+     */
+
+    priv->funcs = *funcs;
+
+    dixSetPrivate(&pScreen->devPrivates, &syncFdScreenPrivateKey, priv);
+    
+    return TRUE;
+}