Adding upstream version 2.2.0.upstream/2.2.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 110 insertions, 0 deletions

diff --git a/src/lib/log/buffer_appender_impl.h b/src/lib/log/buffer_appender_impl.h
new file mode 100644
index 0000000..10290b5
--- /dev/null
+++ b/src/lib/log/buffer_appender_impl.h
@@ -0,0 +1,110 @@
+// Copyright (C) 2012-2015 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef LOG_BUFFER_H
+#define LOG_BUFFER_H
+
+#include <exceptions/exceptions.h>
+
+#include <log4cplus/logger.h>
+#include <log4cplus/spi/loggingevent.h>
+#include <boost/shared_ptr.hpp>
+
+namespace isc {
+namespace log {
+namespace internal {
+
+/// \brief Buffer add after flush
+///
+/// This exception is thrown if the log buffer's add() method
+/// is called after the log buffer has been flushed; the buffer
+/// is only supposed to be used once (until the first time a
+/// logger specification is processed)
+class LogBufferAddAfterFlush : public isc::Exception {
+public:
+    LogBufferAddAfterFlush(const char* file, size_t line, const char* what) :
+        isc::Exception(file, line, what)
+    {}
+};
+
+/// Convenience typedef for a pointer to a log event
+typedef boost::shared_ptr<log4cplus::spi::InternalLoggingEvent> LogEventPtr;
+
+/// Convenience typedef for a pair string/logeventptr, the string representing
+/// the logger level, as returned by LogLevelManager::toString() at the
+/// time of initial logging
+typedef std::pair<std::string, LogEventPtr> LevelAndEvent;
+
+/// Convenience typedef for a vector of LevelAndEvent instances
+typedef std::vector<LevelAndEvent> LogEventList;
+
+/// \brief Buffering Logger Appender
+///
+/// This class can be set as an Appender for log4cplus loggers,
+/// and is used to store logging events; it simply keeps any
+/// event that is passed to \c append(), and will replay them to the
+/// logger that they were originally created for when \c flush() is
+/// called.
+///
+/// The idea is that initially, a program may want to do some logging,
+/// but does not know where to yet (for instance because it has yet to
+/// read and parse its configuration). Any log messages before this time
+/// would normally go to some default (say, stdout), and be lost in the
+/// real logging destination. By buffering them (and flushing them once
+/// the logger has been configured), these log messages are kept in a
+/// consistent place, and are not lost.
+///
+/// Given this goal, this class has an extra check; it will raise
+/// an exception if \c append() is called after flush().
+///
+/// If the BufferAppender instance is destroyed before being flushed,
+/// it will dump any event it has left to stdout.
+class BufferAppender : public log4cplus::Appender {
+public:
+    /// \brief Constructor
+    ///
+    /// Constructs a BufferAppender that buffers log evens
+    BufferAppender() : flushed_(false) {}
+
+    /// \brief Destructor
+    ///
+    /// Any remaining events are flushed to stdout (there should
+    /// only be any events remaining if flush() was never called)
+    virtual ~BufferAppender();
+
+    /// \brief Close the appender
+    ///
+    /// This class has no specialized handling for this method
+    virtual void close() {}
+
+    /// \brief Flush the internal buffer
+    ///
+    /// Events that have been stored (after calls to \c append()
+    /// are replayed to the logger. Should only be called after
+    /// new appenders have been set to the logger.
+    void flush();
+
+    /// \brief Returns the number of stored logging events
+    ///
+    /// Mainly useful for testing
+    size_t getBufferSize() const;
+
+protected:
+    virtual void append(const log4cplus::spi::InternalLoggingEvent& event);
+private:
+    /// \brief Helper for the destructor, flush events to stdout
+    void flushStdout();
+
+    LogEventList stored_;
+    bool flushed_;
+};
+
+} // end namespace internal
+} // end namespace log
+} // end namespace isc
+
+#endif // LOG_BUFFER_H
+