1 files changed, 127 insertions, 0 deletions
diff --git a/src/ipa/rpi/controller/metadata.h b/src/ipa/rpi/controller/metadata.h
new file mode 100644
index 00000000..a232dcb1
--- /dev/null
+++ b/src/ipa/rpi/controller/metadata.h
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+/*
+ * Copyright (C) 2019-2021, Raspberry Pi Ltd
+ *
+ * metadata.h - general metadata class
+ */
+#pragma once
+
+/* A simple class for carrying arbitrary metadata, for example about an image. */
+
+#include <any>
+#include <map>
+#include <mutex>
+#include <string>
+
+#include <libcamera/base/thread_annotations.h>
+
+namespace RPiController {
+
+class LIBCAMERA_TSA_CAPABILITY("mutex") Metadata
+{
+public:
+	Metadata() = default;
+
+	Metadata(Metadata const &other)
+	{
+		std::scoped_lock otherLock(other.mutex_);
+		data_ = other.data_;
+	}
+
+	Metadata(Metadata &&other)
+	{
+		std::scoped_lock otherLock(other.mutex_);
+		data_ = std::move(other.data_);
+		other.data_.clear();
+	}
+
+	template<typename T>
+	void set(std::string const &tag, T const &value)
+	{
+		std::scoped_lock lock(mutex_);
+		data_[tag] = value;
+	}
+
+	template<typename T>
+	int get(std::string const &tag, T &value) const
+	{
+		std::scoped_lock lock(mutex_);
+		auto it = data_.find(tag);
+		if (it == data_.end())
+			return -1;
+		value = std::any_cast<T>(it->second);
+		return 0;
+	}
+
+	void clear()
+	{
+		std::scoped_lock lock(mutex_);
+		data_.clear();
+	}
+
+	Metadata &operator=(Metadata const &other)
+	{
+		std::scoped_lock lock(mutex_, other.mutex_);
+		data_ = other.data_;
+		return *this;
+	}
+
+	Metadata &operator=(Metadata &&other)
+	{
+		std::scoped_lock lock(mutex_, other.mutex_);
+		data_ = std::move(other.data_);
+		other.data_.clear();
+		return *this;
+	}
+
+	void merge(Metadata &other)
+	{
+		std::scoped_lock lock(mutex_, other.mutex_);
+		data_.merge(other.data_);
+	}
+
+	void mergeCopy(const Metadata &other)
+	{
+		std::scoped_lock lock(mutex_, other.mutex_);
+		/*
+		 * If the metadata key exists, ignore this item and copy only
+		 * unique key/value pairs.
+		 */
+		data_.insert(other.data_.begin(), other.data_.end());
+	}
+
+	template<typename T>
+	T *getLocked(std::string const &tag)
+	{
+		/*
+		 * This allows in-place access to the Metadata contents,
+		 * for which you should be holding the lock.
+		 */
+		auto it = data_.find(tag);
+		if (it == data_.end())
+			return nullptr;
+		return std::any_cast<T>(&it->second);
+	}
+
+	template<typename T>
+	void setLocked(std::string const &tag, T const &value)
+	{
+		/* Use this only if you're holding the lock yourself. */
+		data_[tag] = value;
+	}
+
+	/*
+	 * Note: use of (lowercase) lock and unlock means you can create scoped
+	 * locks with the standard lock classes.
+	 * e.g. std::lock_guard<RPiController::Metadata> lock(metadata)
+	 */
+	void lock() LIBCAMERA_TSA_ACQUIRE() { mutex_.lock(); }
+	auto try_lock() LIBCAMERA_TSA_ACQUIRE() { return mutex_.try_lock(); }
+	void unlock() LIBCAMERA_TSA_RELEASE() { mutex_.unlock(); }
+
+private:
+	mutable std::mutex mutex_;
+	std::map<std::string, std::any> data_;
+};
+
+} /* namespace RPiController */