git-svn-id: http://webrtc.googlecode.com/svn/trunk@6 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/system_wrappers/interface/trace.h b/system_wrappers/interface/trace.h
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+/*
+ * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+// System independant wrapper for logging runtime information to file.
+// Note: All log messages will be written to the same trace file.
+// Note: If to many messages are written to file there will be a build up of
+// messages. Apply filtering to avoid that.
+#ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_TRACE_H_
+#define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_TRACE_H_
+
+#include "common_types.h"
+#include "typedefs.h"
+
+#ifdef WEBRTC_NO_TRACE
+ #define WEBRTC_TRACE
+#else
+ // Ideally we would use __VA_ARGS__ but it's not supported by all compilers
+ // such as VS2003 (it's supported in VS2005). TODO (hellner) why
+ // would this be better than current implementation (not convinced)?
+ #define WEBRTC_TRACE Trace::Add
+#endif
+
+namespace webrtc {
+class Trace
+{
+public:
+
+ // Increments the reference count to the trace.
+ static void CreateTrace();
+ // Decrements the reference count to the trace.
+ static void ReturnTrace();
+ // Note: any instance that writes to the trace file should increment and
+ // decrement the reference count on construction and destruction
+ // respectively
+
+ // Specifies what type of messages should be written to the trace file. The
+ // filter parameter is a bitmask where each message type is enumerated by
+ // the TraceLevel enumerator. TODO (hellner) why is the
+ // TraceLevel enumerator not defined in this file?
+ static WebRtc_Word32 SetLevelFilter(const WebRtc_UWord32 filter);
+
+ // Returns what type of messages are written to the trace file.
+ static WebRtc_Word32 LevelFilter(WebRtc_UWord32& filter);
+
+ // Sets the file name. If addFileCounter is false the same file will be
+ // reused when it fills up. If it's true a new file with incremented name
+ // will be used.
+ static WebRtc_Word32 SetTraceFile(const WebRtc_Word8* fileName,
+ const bool addFileCounter = false);
+
+ // Returns the name of the file that the trace is currently writing to.
+ static WebRtc_Word32 TraceFile(WebRtc_Word8 fileName[1024]);
+
+ // Registers callback to receive trace messages. TODO (hellner)
+ // why not use OutStream instead? Why is TraceCallback not defined in this
+ // file
+ static WebRtc_Word32 SetTraceCallback(TraceCallback* callback);
+
+ // Adds a trace message for writing to file. The message is put in a queue
+ // for writing to file whenever possible for performance reasons. I.e. there
+ // is a crash it is possible that the last, vital logs are not logged yet.
+ // level is the the type of message to log. If that type of messages is
+ // filtered it will not be written to file. module is an identifier for what
+ // part of the code the message is comming.
+ // id is an identifier that should be unique for that set of classes that
+ // are associated (e.g. all instances owned by an engine).
+ // msg and the elipsis are the same as e.g. sprintf.
+ // TODO (hellner) Why is TraceModule not defined in this file?
+ static void Add(const TraceLevel level,
+ const TraceModule module,
+ const WebRtc_Word32 id,
+ const char* msg, ...);
+
+};
+} // namespace webrtc
+#endif // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_TRACE_H_