wayland/commit-timing: Add support for the commit-timing-v1 protocol

Allow clients to add timestamps to content updates.

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/3355>

src/meson.build

@@ -606,6 +606,7 @@ if have_wayland
     'wayland/meta-wayland-client-private.h',
     'wayland/meta-wayland-color-management.c',
     'wayland/meta-wayland-color-management.h',
+    'wayland/meta-wayland-commit-timing.c',
     'wayland/meta-wayland-cursor-surface.c',
     'wayland/meta-wayland-cursor-surface.h',
     'wayland/meta-wayland-data-device.c',
@@ -1128,6 +1129,7 @@ if have_wayland
     ['linux-drm-syncobj-v1', 'private', ],
     ['color-management-v1', 'private', ],
     ['session-management-v1', 'private', ],
+    ['commit-timing', 'staging', 'v1', ],
   ]
   if have_wayland_eglstream
     wayland_eglstream_protocols_dir = wayland_eglstream_protocols_dep.get_variable('pkgdatadir')

src/wayland/meta-wayland-commit-timing.c

@@ -0,0 +1,196 @@
+/*
+ * Copyright (C) 2023 Valve Corporation
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <wayland-server.h>
+
+#include "commit-timing-v1-server-protocol.h"
+#include "wayland/meta-wayland-commit-timing.h"
+#include "wayland/meta-wayland-private.h"
+#include "wayland/meta-wayland-versions.h"
+
+typedef struct _MetaWaylandCommitTimerSurface
+{
+  MetaWaylandSurface *surface;
+  gulong destroy_handler_id;
+} MetaWaylandCommitTimerSurface;
+
+static void
+commit_timer_destructor (struct wl_resource *resource)
+{
+  MetaWaylandCommitTimerSurface *timer = wl_resource_get_user_data (resource);
+
+  if (timer->surface)
+    {
+      g_object_set_data (G_OBJECT (timer->surface),
+                         "-meta-wayland-commit-timer", NULL);
+
+      g_clear_signal_handler (&timer->destroy_handler_id, timer->surface);
+    }
+
+  g_free (timer);
+}
+
+static void
+commit_timer_destroy (struct wl_client   *client,
+                      struct wl_resource *resource)
+{
+  wl_resource_destroy (resource);
+}
+
+static void
+commit_timer_set_target_time (struct wl_client   *client,
+                              struct wl_resource *resource,
+                              uint32_t            sec_hi,
+                              uint32_t            sec_lo,
+                              uint32_t            nsec)
+{
+  MetaWaylandCommitTimerSurface *timer = wl_resource_get_user_data (resource);
+  MetaWaylandSurface *surface = timer->surface;
+  MetaWaylandSurfaceState *pending;
+  uint64_t target_time_us;
+
+  if (!surface)
+    {
+      wl_resource_post_error (resource,
+                              WP_COMMIT_TIMER_V1_ERROR_SURFACE_DESTROYED,
+                              "Surface destroyed");
+      return;
+    }
+
+  pending = meta_wayland_surface_get_pending_state (surface);
+
+  if (pending->has_target_time)
+    {
+      wl_resource_post_error (resource,
+                              WP_COMMIT_TIMER_V1_ERROR_TIMESTAMP_EXISTS,
+                              "Commit already has timestamp");
+      return;
+    }
+
+  if (nsec > 999999999)
+    {
+      wl_resource_post_error (resource,
+                              WP_COMMIT_TIMER_V1_ERROR_INVALID_TIMESTAMP,
+                              "Timestamp is invalid");
+      return;
+    }
+
+  target_time_us = (((uint64_t) sec_hi << 32) + sec_lo) * 1000000;
+  target_time_us += nsec / 1000;
+
+  pending->has_target_time = TRUE;
+  pending->target_time_us = target_time_us;
+}
+
+static const struct wp_commit_timer_v1_interface meta_wayland_commit_timer_interface =
+{
+  commit_timer_set_target_time,
+  commit_timer_destroy,
+};
+
+static void
+commit_timing_manager_destroy (struct wl_client   *client,
+                               struct wl_resource *resource)
+{
+  wl_resource_destroy (resource);
+}
+
+static void
+on_surface_destroyed (MetaWaylandSurface            *surface,
+                      MetaWaylandCommitTimerSurface *timer)
+{
+  timer->surface = NULL;
+}
+
+static void
+commit_timing_manager_get_timer (struct wl_client   *client,
+                                 struct wl_resource *resource,
+                                 uint32_t            id,
+                                 struct wl_resource *surface_resource)
+{
+  MetaWaylandSurface *surface = wl_resource_get_user_data (surface_resource);
+  MetaWaylandCommitTimerSurface *timer;
+  struct wl_resource *timer_resource;
+
+  timer = g_object_get_data (G_OBJECT (surface), "-meta-wayland-commit-timer");
+
+  if (timer)
+    {
+      wl_resource_post_error (resource,
+                              WP_COMMIT_TIMING_MANAGER_V1_ERROR_COMMIT_TIMER_EXISTS,
+                              "Commit timing resource already exists on surface");
+      return;
+    }
+
+  timer_resource = wl_resource_create (client,
+                                       &wp_commit_timer_v1_interface,
+                                       wl_resource_get_version (resource),
+                                       id);
+
+  timer = g_new0 (MetaWaylandCommitTimerSurface, 1);
+  timer->surface = surface;
+
+  timer->destroy_handler_id =
+    g_signal_connect (surface,
+                      "destroy",
+                      G_CALLBACK (on_surface_destroyed),
+                      timer);
+
+  g_object_set_data (G_OBJECT (surface), "-meta-wayland-commit-timer", timer);
+
+  wl_resource_set_implementation (timer_resource,
+                                  &meta_wayland_commit_timer_interface,
+                                  timer,
+                                  commit_timer_destructor);
+}
+
+static const struct wp_commit_timing_manager_v1_interface meta_wayland_commit_timing_manager_interface =
+{
+  commit_timing_manager_destroy,
+  commit_timing_manager_get_timer,
+};
+
+static void
+bind_commit_timing (struct wl_client *client,
+                    void             *data,
+                    uint32_t          version,
+                    uint32_t          id)
+{
+  struct wl_resource *resource;
+
+  resource = wl_resource_create (client,
+                                 &wp_commit_timing_manager_v1_interface,
+                                 version, id);
+
+  wl_resource_set_implementation (resource,
+                                  &meta_wayland_commit_timing_manager_interface,
+                                  NULL, NULL);
+}
+
+void
+meta_wayland_commit_timing_init (MetaWaylandCompositor *compositor)
+{
+  if (wl_global_create (compositor->wayland_display,
+                        &wp_commit_timing_manager_v1_interface,
+                        META_WP_COMMIT_TIMING_V1_VERSION,
+                        NULL,
+                        bind_commit_timing) == NULL)
+    g_error ("Failed to register a global commit_timing_manager object");
+}

src/wayland/meta-wayland-commit-timing.h

@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2023 Valve Corporation
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#pragma once
+
+#include <glib.h>
+
+#include "wayland/meta-wayland-types.h"
+
+void meta_wayland_commit_timing_init (MetaWaylandCompositor *compositor);

src/wayland/meta-wayland-surface-private.h

@@ -23,6 +23,7 @@
 
 #include "backends/meta-monitor-manager-private.h"
 #include "clutter/clutter.h"
+#include "commit-timing-v1-server-protocol.h"
 #include "compositor/meta-shaped-texture-private.h"
 #include "compositor/meta-surface-actor.h"
 #include "meta/meta-cursor-tracker.h"

src/wayland/meta-wayland-versions.h

@@ -63,3 +63,4 @@
 #define META_XDG_SESSION_MANAGER_V1_VERSION 1
 #define META_WP_SYSTEM_BELL_V1_VERSION 1
 #define META_XDG_TOPLEVEL_DRAG_VERSION 1
+#define META_WP_COMMIT_TIMING_V1_VERSION 1

src/wayland/meta-wayland.c

@@ -40,6 +40,7 @@
 #include "wayland/meta-wayland-activation.h"
 #include "wayland/meta-wayland-buffer.h"
 #include "wayland/meta-wayland-color-management.h"
+#include "wayland/meta-wayland-commit-timing.h"
 #include "wayland/meta-wayland-data-device.h"
 #include "wayland/meta-wayland-dma-buf.h"
 #include "wayland/meta-wayland-egl-stream.h"
@@ -971,6 +972,7 @@ meta_wayland_compositor_new (MetaContext *context)
 #ifdef HAVE_NATIVE_BACKEND
   meta_wayland_drm_lease_manager_init (compositor);
 #endif
+  meta_wayland_commit_timing_init (compositor);
 
 #ifdef HAVE_WAYLAND_EGLSTREAM
   {