1 files changed, 67 insertions, 0 deletions
diff --git a/cros_gralloc/cros_gralloc_buffer_metadata.h b/cros_gralloc/cros_gralloc_buffer_metadata.h
new file mode 100644
index 0000000..361a472
--- /dev/null
+++ b/cros_gralloc/cros_gralloc_buffer_metadata.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef CROSGRALLOC4METADATA_H
+#define CROSGRALLOC4METADATA_H
+
+#include <optional>
+#include <type_traits>
+
+#include <aidl/android/hardware/graphics/common/BlendMode.h>
+#include <aidl/android/hardware/graphics/common/Cta861_3.h>
+#include <aidl/android/hardware/graphics/common/Dataspace.h>
+#include <aidl/android/hardware/graphics/common/Smpte2086.h>
+
+#include "cros_gralloc_helpers.h"
+
+// Simple replacement for std::optional which is not guarenteed to be memory layout
+// stable across ABIs.
+template <typename T> struct cros_buffer_optional {
+
+	enum class state : uint32_t { VACANT, OCCUPIED };
+
+	cros_buffer_optional() = default;
+
+	cros_buffer_optional(std::optional<T> v) : occupancy(v ? state::OCCUPIED : state::VACANT)
+	{
+		if (v) {
+			value = *v;
+		}
+	}
+
+	std::optional<T> to_std_optional() const
+	{
+		return occupancy == state::VACANT ? std::nullopt : std::make_optional(value);
+	}
+
+	state occupancy = state::VACANT;
+	T value;
+};
+
+/*
+ * The metadata for cros_gralloc_buffer-s that should reside in a shared memory region
+ * instead of directly in cros_gralloc_handle-s.
+ *
+ * Any metadata that is mutable must be stored in this shared memory region as
+ * cros_gralloc_handle-s can not be tracked and updated across processes.
+ */
+struct cros_gralloc_buffer_metadata {
+	/*
+	 * Name is stored in the shared memory metadata to simplify cros_gralloc_handle
+	 * creation. This allows us to keep handles small while avoiding variable sized
+	 * handles.
+	 */
+	char name[CROS_GRALLOC_BUFFER_METADATA_MAX_NAME_SIZE];
+	aidl::android::hardware::graphics::common::BlendMode blend_mode;
+	aidl::android::hardware::graphics::common::Dataspace dataspace;
+	cros_buffer_optional<aidl::android::hardware::graphics::common::Cta861_3> cta861_3;
+	cros_buffer_optional<aidl::android::hardware::graphics::common::Smpte2086> smpte2086;
+};
+
+static_assert(std::is_standard_layout_v<cros_gralloc_buffer_metadata>);
+static_assert(std::is_trivially_copyable_v<cros_gralloc_buffer_metadata>);
+
+#endif