Journal improvements

modules/beast_core/diagnostic/Journal.cpp

@@ -17,7 +17,14 @@
 */
 //==============================================================================
 
-Journal::Sink* Journal::getNullSink ()
+bool Journal::Sink::active (Severity)
+{
+    return true;
+}
+
+//------------------------------------------------------------------------------
+
+Journal::Sink& Journal::getNullSink ()
 {
     // A Sink that does nothing.
     class NullSink : public Sink
@@ -33,6 +40,144 @@ Journal::Sink* Journal::getNullSink ()
         }
     };
 
-    return SharedSingleton <NullSink>::get (
+    return *SharedSingleton <NullSink>::get (
         SingletonLifetime::neverDestroyed);
 }
+
+//------------------------------------------------------------------------------
+
+Journal::ScopedStream::ScopedStream (Stream const& stream)
+    : m_sink (stream.sink())
+    , m_severity (stream.severity())
+{
+}
+
+Journal::ScopedStream::ScopedStream (ScopedStream const& other)
+    : m_sink (other.m_sink)
+    , m_severity (other.m_severity)
+{
+}
+
+Journal::ScopedStream::ScopedStream (Stream const& stream, std::ostream& manip (std::ostream&))
+    : m_sink (stream.sink())
+    , m_severity (stream.severity())
+{
+    m_ostream << manip;
+}
+
+Journal::ScopedStream::~ScopedStream ()
+{
+    if (m_sink.active (m_severity))
+    {
+        if (! m_ostream.str().empty())
+            m_sink.write (m_severity, m_ostream.str());
+    }
+}
+
+std::ostream& Journal::ScopedStream::operator<< (std::ostream& manip (std::ostream&)) const
+{
+    return m_ostream << manip;
+}
+
+std::ostringstream& Journal::ScopedStream::ostream () const
+{
+    return m_ostream;
+}
+
+//------------------------------------------------------------------------------
+
+Journal::Stream::Stream ()
+    : m_sink (&getNullSink ())
+    , m_severity (kFatal)
+{
+}
+
+Journal::Stream::Stream (Sink& sink, Severity severity)
+    : m_sink (&sink)
+    , m_severity (severity)
+{
+}
+
+Journal::Stream::Stream (Stream const& other)
+    : m_sink (other.m_sink)
+    , m_severity (other.m_severity)
+{
+}
+
+bool Journal::Stream::active () const
+{
+    return m_sink->active (m_severity);
+}
+
+Journal::Sink& Journal::Stream::sink () const
+{
+    return *m_sink;
+}
+
+Journal::Severity Journal::Stream::severity () const
+{
+    return m_severity;
+}
+
+Journal::Stream& Journal::Stream::operator= (Stream const& other)
+{
+    m_sink = other.m_sink;
+    m_severity = other.m_severity;
+    return *this;
+}
+
+Journal::ScopedStream Journal::Stream::operator<< (std::ostream& manip (std::ostream&)) const
+{
+    return ScopedStream (*this, manip);
+}
+
+//------------------------------------------------------------------------------
+
+Journal::Journal ()
+    : m_sink  (&getNullSink())
+    , trace   (stream (kTrace))
+    , debug   (stream (kDebug))
+    , info    (stream (kInfo))
+    , warning (stream (kWarning))
+    , error   (stream (kError))
+    , fatal   (stream (kFatal))
+{
+}
+
+Journal::Journal (Sink& sink)
+    : m_sink  (&sink)
+    , trace   (stream (kTrace))
+    , debug   (stream (kDebug))
+    , info    (stream (kInfo))
+    , warning (stream (kWarning))
+    , error   (stream (kError))
+    , fatal   (stream (kFatal))
+{
+}
+
+Journal::Journal (Journal const& other)
+    : m_sink  (other.m_sink)
+    , trace   (stream (kTrace))
+    , debug   (stream (kDebug))
+    , info    (stream (kInfo))
+    , warning (stream (kWarning))
+    , error   (stream (kError))
+    , fatal   (stream (kFatal))
+{
+}
+
+Journal::~Journal ()
+{
+}
+
+Journal::Stream Journal::stream (Severity severity) const
+{
+    return Stream (*m_sink, severity);
+}
+
+/** Returns `true` if the sink logs messages at that severity. */
+bool Journal::active (Severity severity) const
+{
+    return m_sink->active (severity);
+}
+