libcamera/base: Move extended base functionality

Move the functionality for the following components to the new
base support library:

 - BoundMethod
 - EventDispatcher
 - EventDispatcherPoll
 - Log
 - Message
 - Object
 - Signal
 - Semaphore
 - Thread
 - Timer

While it would be preferable to see these split to move one component
per commit, these components are all interdependent upon each other,
which leaves us with one big change performing the move for all of them.

Reviewed-by: Hirokazu Honda <hiroh@chromium.org>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

1 files changed, 130 insertions, 0 deletions

diff --git a/include/libcamera/base/log.h b/include/libcamera/base/log.h
new file mode 100644
index 00000000..b93c947a
--- /dev/null
+++ b/include/libcamera/base/log.h
@@ -0,0 +1,130 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2018, Google Inc.
+ *
+ * log.h - Logging infrastructure
+ */
+#ifndef __LIBCAMERA_BASE_LOG_H__
+#define __LIBCAMERA_BASE_LOG_H__
+
+#include <chrono>
+#include <sstream>
+
+#include <libcamera/base/class.h>
+#include <libcamera/base/utils.h>
+
+namespace libcamera {
+
+enum LogSeverity {
+	LogInvalid = -1,
+	LogDebug = 0,
+	LogInfo,
+	LogWarning,
+	LogError,
+	LogFatal,
+};
+
+class LogCategory
+{
+public:
+	explicit LogCategory(const char *name);
+
+	const char *name() const { return name_; }
+	LogSeverity severity() const { return severity_; }
+	void setSeverity(LogSeverity severity);
+
+	static const LogCategory &defaultCategory();
+
+private:
+	const char *name_;
+	LogSeverity severity_;
+};
+
+#define LOG_DECLARE_CATEGORY(name)					\
+extern const LogCategory &_LOG_CATEGORY(name)();
+
+#define LOG_DEFINE_CATEGORY(name)					\
+const LogCategory &_LOG_CATEGORY(name)()				\
+{									\
+	/* The instance will be deleted by the Logger destructor. */	\
+	static LogCategory *category = new LogCategory(#name);		\
+	return *category;						\
+}
+
+class LogMessage
+{
+public:
+	LogMessage(const char *fileName, unsigned int line,
+		   const LogCategory &category, LogSeverity severity);
+
+	LogMessage(LogMessage &&);
+	~LogMessage();
+
+	std::ostream &stream() { return msgStream_; }
+
+	const utils::time_point &timestamp() const { return timestamp_; }
+	LogSeverity severity() const { return severity_; }
+	const LogCategory &category() const { return category_; }
+	const std::string &fileInfo() const { return fileInfo_; }
+	const std::string msg() const { return msgStream_.str(); }
+
+private:
+	LIBCAMERA_DISABLE_COPY(LogMessage)
+
+	void init(const char *fileName, unsigned int line);
+
+	std::ostringstream msgStream_;
+	const LogCategory &category_;
+	LogSeverity severity_;
+	utils::time_point timestamp_;
+	std::string fileInfo_;
+};
+
+class Loggable
+{
+public:
+	virtual ~Loggable();
+
+protected:
+	virtual std::string logPrefix() const = 0;
+
+	LogMessage _log(const LogCategory *category, LogSeverity severity,
+			const char *fileName = __builtin_FILE(),
+			unsigned int line = __builtin_LINE()) const;
+};
+
+LogMessage _log(const LogCategory *category, LogSeverity severity,
+		const char *fileName = __builtin_FILE(),
+		unsigned int line = __builtin_LINE());
+
+#ifndef __DOXYGEN__
+#define _LOG_CATEGORY(name) logCategory##name
+
+#define _LOG1(severity) \
+	_log(nullptr, Log##severity).stream()
+#define _LOG2(category, severity) \
+	_log(&_LOG_CATEGORY(category)(), Log##severity).stream()
+
+/*
+ * Expand the LOG() macro to _LOG1() or _LOG2() based on the number of
+ * arguments.
+ */
+#define _LOG_MACRO(_1, _2, NAME, ...) NAME
+#define LOG(...) _LOG_MACRO(__VA_ARGS__, _LOG2, _LOG1)(__VA_ARGS__)
+#else /* __DOXYGEN___ */
+#define LOG(category, severity)
+#endif /* __DOXYGEN__ */
+
+#ifndef NDEBUG
+#define ASSERT(condition) static_cast<void>(({                          \
+	if (!(condition))                                               \
+		LOG(Fatal) << "assertion \"" #condition "\" failed in " \
+			   << __func__ << "()";                         \
+}))
+#else
+#define ASSERT(condition) static_cast<void>(false && (condition))
+#endif
+
+} /* namespace libcamera */
+
+#endif /* __LIBCAMERA_BASE_LOG_H__ */