Query DRI2 for the driver name.

If the VDPAU_DRIVER environment variable is not set, use DRI2Connect to query
the VDPAU driver name from the X server.
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>

configure.ac

@@ -20,6 +20,23 @@ PKG_CHECK_MODULES(X11, x11)
 AC_SUBST(X11_CFLAGS)
 AC_SUBST(X11_LIBS)
 
+# Check for optional dependencies.
+AC_ARG_ENABLE(dri2, AS_HELP_STRING([--disable-dri2], [Disable driver name query through DRI2 (default: auto)]), [DRI2=$enableval], [DRI2=auto])
+PKG_CHECK_MODULES(dri2proto, dri2proto >= 2.2, [HAVE_DRI2PROTO=yes], [HAVE_DRI2PROTO=no])
+case "$DRI2,$HAVE_DRI2PROTO" in
+    yes,no)
+        AC_MSG_ERROR([DRI2 queries require dri2proto >= 2.2])
+        ;;
+    yes,yes | auto,yes)
+        AC_DEFINE(DRI2, 1, [Request driver name from DRI2])
+        DRI2=yes
+        PKG_CHECK_MODULES(XEXT, xext)
+        AC_SUBST([XEXT_CFLAGS])
+        AC_SUBST([XEXT_LIBS])
+        ;;
+esac
+AM_CONDITIONAL(DRI2, test "x$DRI2" = xyes)
+
 dnl Check to see if dlopen is in default libraries (like Solaris, which
 dnl has it in libc), or if libdl is needed to get it.
 AC_CHECK_FUNC([dlopen], [],

src/Makefile.am

 AM_CFLAGS = \
     -I$(top_srcdir)/include \
     -DVDPAU_MODULEDIR="\"$(moduledir)\"" \
-    $(X11_CFLAGS)
+    $(X11_CFLAGS) \
+    $(XEXT_CFLAGS)
 
 lib_LTLIBRARIES = libvdpau.la
 
 libvdpau_la_SOURCES = \
-    vdpau_wrapper.c
+    vdpau_wrapper.c \
+    $(DRI2_SOURCES)
+
+if DRI2
+    DRI2_SOURCES = \
+        mesa_dri2.c \
+        mesa_dri2.h
+endif
 
 libvdpau_la_LIBADD = \
-    $(DLOPEN_LIBS)
+    $(DLOPEN_LIBS) \
+    $(XEXT_LIBS)
 
 libvdpau_la_LDFLAGS = -version-info 1:0:0 -no-undefined
 

src/mesa_dri2.c

+/*
+ * Copyright © 2008 Red Hat, Inc.
+ * Copyright © 2010 NVIDIA Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Soft-
+ * ware"), to deal in the Software without restriction, including without
+ * limitation the rights to use, copy, modify, merge, publish, distribute,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, provided that the above copyright
+ * notice(s) and this permission notice appear in all copies of the Soft-
+ * ware and that both the above copyright notice(s) and this permission
+ * notice appear in supporting documentation.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
+ * ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY
+ * RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN
+ * THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSE-
+ * QUENTIAL 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 PERFOR-
+ * MANCE OF THIS SOFTWARE.
+ *
+ * Except as contained in this notice, the name of a copyright holder shall
+ * not be used in advertising or otherwise to promote the sale, use or
+ * other dealings in this Software without prior written authorization of
+ * the copyright holder.
+ *
+ * Authors:
+ *   Kristian Høgsberg (krh@redhat.com)
+ *   Modified for VDPAU by Aaron Plattner (aplattner@nvidia.com)
+ */
+
+
+#define NEED_REPLIES
+#include <X11/Xlibint.h>
+#include <X11/extensions/Xext.h>
+#include <X11/extensions/extutil.h>
+#include <X11/extensions/dri2proto.h>
+#include "mesa_dri2.h"
+
+static char dri2ExtensionName[] = DRI2_NAME;
+static XExtensionInfo *dri2Info;
+static XEXT_GENERATE_CLOSE_DISPLAY (DRI2CloseDisplay, dri2Info)
+
+static /* const */ XExtensionHooks dri2ExtensionHooks = {
+  NULL,                   /* create_gc */
+  NULL,                   /* copy_gc */
+  NULL,                   /* flush_gc */
+  NULL,                   /* free_gc */
+  NULL,                   /* create_font */
+  NULL,                   /* free_font */
+  DRI2CloseDisplay,       /* close_display */
+  NULL,                   /* wire_to_event */
+  NULL,                   /* event_to_wire */
+  NULL,                   /* error */
+  NULL,                   /* error_string */
+};
+
+static XEXT_GENERATE_FIND_DISPLAY (DRI2FindDisplay,
+                                   dri2Info,
+                                   dri2ExtensionName,
+                                   &dri2ExtensionHooks,
+                                   0, NULL)
+
+Bool
+_vdp_DRI2QueryExtension(Display * dpy, int *eventBase, int *errorBase)
+{
+   XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+
+   if (XextHasExtension(info)) {
+      *eventBase = info->codes->first_event;
+      *errorBase = info->codes->first_error;
+      return True;
+   }
+
+   return False;
+}
+
+Bool
+_vdp_DRI2QueryVersion(Display * dpy, int *major, int *minor)
+{
+   XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+   xDRI2QueryVersionReply rep;
+   xDRI2QueryVersionReq *req;
+
+   XextCheckExtension(dpy, info, dri2ExtensionName, False);
+
+   LockDisplay(dpy);
+   GetReq(DRI2QueryVersion, req);
+   req->reqType = info->codes->major_opcode;
+   req->dri2ReqType = X_DRI2QueryVersion;
+   req->majorVersion = DRI2_MAJOR;
+   req->minorVersion = DRI2_MINOR;
+   if (!_XReply(dpy, (xReply *) & rep, 0, xFalse)) {
+      UnlockDisplay(dpy);
+      SyncHandle();
+      return False;
+   }
+   *major = rep.majorVersion;
+   *minor = rep.minorVersion;
+   UnlockDisplay(dpy);
+   SyncHandle();
+
+   return True;
+}
+
+Bool
+_vdp_DRI2Connect(Display * dpy, XID window, char **driverName, char **deviceName)
+{
+   XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+   xDRI2ConnectReply rep;
+   xDRI2ConnectReq *req;
+
+   XextCheckExtension(dpy, info, dri2ExtensionName, False);
+
+   LockDisplay(dpy);
+   GetReq(DRI2Connect, req);
+   req->reqType = info->codes->major_opcode;
+   req->dri2ReqType = X_DRI2Connect;
+   req->window = window;
+   req->driverType = DRI2DriverVDPAU;
+   if (!_XReply(dpy, (xReply *) & rep, 0, xFalse)) {
+      UnlockDisplay(dpy);
+      SyncHandle();
+      return False;
+   }
+
+   if (rep.driverNameLength == 0 && rep.deviceNameLength == 0) {
+      UnlockDisplay(dpy);
+      SyncHandle();
+      return False;
+   }
+
+   *driverName = Xmalloc(rep.driverNameLength + 1);
+   if (*driverName == NULL) {
+      _XEatData(dpy,
+                ((rep.driverNameLength + 3) & ~3) +
+                ((rep.deviceNameLength + 3) & ~3));
+      UnlockDisplay(dpy);
+      SyncHandle();
+      return False;
+   }
+   _XReadPad(dpy, *driverName, rep.driverNameLength);
+   (*driverName)[rep.driverNameLength] = '\0';
+
+   *deviceName = Xmalloc(rep.deviceNameLength + 1);
+   if (*deviceName == NULL) {
+      Xfree(*driverName);
+      _XEatData(dpy, ((rep.deviceNameLength + 3) & ~3));
+      UnlockDisplay(dpy);
+      SyncHandle();
+      return False;
+   }
+   _XReadPad(dpy, *deviceName, rep.deviceNameLength);
+   (*deviceName)[rep.deviceNameLength] = '\0';
+
+   UnlockDisplay(dpy);
+   SyncHandle();
+
+   return True;
+}

src/mesa_dri2.h

+/*
+ * Copyright © 2007,2008 Red Hat, Inc.
+ * Copyright © 2010 NVIDIA Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Soft-
+ * ware"), to deal in the Software without restriction, including without
+ * limitation the rights to use, copy, modify, merge, publish, distribute,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, provided that the above copyright
+ * notice(s) and this permission notice appear in all copies of the Soft-
+ * ware and that both the above copyright notice(s) and this permission
+ * notice appear in supporting documentation.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABIL-
+ * ITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY
+ * RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN
+ * THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSE-
+ * QUENTIAL 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 PERFOR-
+ * MANCE OF THIS SOFTWARE.
+ *
+ * Except as contained in this notice, the name of a copyright holder shall
+ * not be used in advertising or otherwise to promote the sale, use or
+ * other dealings in this Software without prior written authorization of
+ * the copyright holder.
+ *
+ * Authors:
+ *   Kristian Høgsberg (krh@redhat.com)
+ *   Modified for VDPAU by Aaron Plattner (aplattner@nvidia.com)
+ */
+
+#ifndef _VDP_DRI2_H_
+#define _VDP_DRI2_H_
+
+#include <X11/extensions/dri2tokens.h>
+
+extern Bool
+_vdp_DRI2QueryExtension(Display * display, int *eventBase, int *errorBase);
+
+extern Bool
+_vdp_DRI2QueryVersion(Display * display, int *major, int *minor);
+
+extern Bool
+_vdp_DRI2Connect(Display * display, XID window, char **driverName,
+                 char **deviceName);
+
+#endif

src/vdpau_wrapper.c

@@ -21,12 +21,20 @@
  * SOFTWARE.
  */
 
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <dlfcn.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <vdpau/vdpau_x11.h>
+#if DRI2
+#include "mesa_dri2.h"
+#include <X11/Xlib.h>
+#endif
 
 typedef void SetDllHandle(
     void * driver_dll_handle
@@ -49,6 +57,36 @@ static void _vdp_wrapper_error_breakpoint(char const * file, int line, char cons
 
 #define DRIVER_LIB_FORMAT "%slibvdpau_%s.so%s"
 
+static char * _vdp_get_driver_name_from_dri2(
+    Display *             display,
+    int                   screen
+)
+{
+    char * driver_name = NULL;
+#if DRI2
+    Window root = RootWindow(display, screen);
+    int event_base, error_base;
+    int major, minor;
+    char * device_name;
+
+    if (!_vdp_DRI2QueryExtension(display, &event_base, &error_base)) {
+        return NULL;
+    }
+
+    if (!_vdp_DRI2QueryVersion(display, &major, &minor) ||
+            (major < 1 || (major == 1 && minor < 2))) {
+        return NULL;
+    }
+
+    if (!_vdp_DRI2Connect(display, root, &driver_name, &device_name)) {
+        return NULL;
+    }
+
+    XFree(device_name);
+#endif /* DRI2 */
+    return driver_name;
+}
+
 VdpStatus vdp_device_create_x11(
     Display *             display,
     int                   screen,
@@ -58,6 +96,7 @@ VdpStatus vdp_device_create_x11(
 )
 {
     char const * vdpau_driver;
+    char * vdpau_driver_dri2 = NULL;
     char         vdpau_driver_lib[PATH_MAX];
     void *       backend_dll;
     char const * vdpau_trace;
@@ -65,8 +104,11 @@ VdpStatus vdp_device_create_x11(
 
     VdpDeviceCreateX11 * vdp_imp_device_create_x11;
 
-    /* FIXME: Determine driver name using an X extension */
     vdpau_driver = getenv("VDPAU_DRIVER");
+    if (!vdpau_driver) {
+        vdpau_driver = vdpau_driver_dri2 =
+            _vdp_get_driver_name_from_dri2(display, screen);
+    }
     if (!vdpau_driver) {
         vdpau_driver = "nvidia";
     }
@@ -75,6 +117,10 @@ VdpStatus vdp_device_create_x11(
                  VDPAU_MODULEDIR "/", vdpau_driver, ".1") >=
             sizeof(vdpau_driver_lib)) {
         fprintf(stderr, "Failed to construct driver path: path too long\n");
+        if (vdpau_driver_dri2) {
+            XFree(vdpau_driver_dri2);
+            vdpau_driver_dri2 = NULL;
+        }
         _VDP_ERROR_BREAKPOINT();
         return VDP_STATUS_NO_IMPLEMENTATION;
     }
@@ -88,6 +134,11 @@ VdpStatus vdp_device_create_x11(
         backend_dll = dlopen(vdpau_driver_lib, RTLD_NOW | RTLD_GLOBAL);
     }
 
+    if (vdpau_driver_dri2) {
+        XFree(vdpau_driver_dri2);
+        vdpau_driver_dri2 = NULL;
+    }
+
     if (!backend_dll) {
         fprintf(stderr, "Failed to open VDPAU backend %s\n", dlerror());
         _VDP_ERROR_BREAKPOINT();