media/base/media_log.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_BASE_MEDIA_LOG_H_
   6 #define MEDIA_BASE_MEDIA_LOG_H_
   7
   8 #include <sstream>
   9 #include <string>
  10
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "media/base/media_export.h"
  14 #include "media/base/media_log_event.h"
  15 #include "media/base/pipeline.h"
  16 #include "media/base/pipeline_status.h"
  17
  18 namespace media {
  19
  20 // Indicates a string should be added to the log.
  21 // First parameter - The string to add to the log.
  22 typedef base::Callback<void(const std::string&)> LogCB;
  23
  24 // Helper class to make it easier to use log_cb like DVLOG().
  25 class LogHelper {
  26  public:
  27   LogHelper(const LogCB& Log_cb);
  28   ~LogHelper();
  29
  30   std::ostream& stream() { return stream_; }
  31
  32  private:
  33   LogCB log_cb_;
  34   std::stringstream stream_;
  35 };
  36
  37 #define MEDIA_LOG(log_cb) LogHelper(log_cb).stream()
  38
  39 class MEDIA_EXPORT MediaLog : public base::RefCountedThreadSafe<MediaLog> {
  40  public:
  41   // Convert various enums to strings.
  42   static const char* EventTypeToString(MediaLogEvent::Type type);
  43   static const char* PipelineStatusToString(PipelineStatus);
  44
  45   MediaLog();
  46
  47   // Add an event to this log. Overriden by inheritors to actually do something
  48   // with it.
  49   virtual void AddEvent(scoped_ptr<MediaLogEvent> event);
  50
  51   // Helper methods to create events and their parameters.
  52   scoped_ptr<MediaLogEvent> CreateEvent(MediaLogEvent::Type type);
  53   scoped_ptr<MediaLogEvent> CreateBooleanEvent(
  54       MediaLogEvent::Type type, const char* property, bool value);
  55   scoped_ptr<MediaLogEvent> CreateStringEvent(
  56       MediaLogEvent::Type type, const char* property, const std::string& value);
  57   scoped_ptr<MediaLogEvent> CreateTimeEvent(
  58       MediaLogEvent::Type type, const char* property, base::TimeDelta value);
  59   scoped_ptr<MediaLogEvent> CreateLoadEvent(const std::string& url);
  60   scoped_ptr<MediaLogEvent> CreateSeekEvent(float seconds);
  61   scoped_ptr<MediaLogEvent> CreatePipelineStateChangedEvent(
  62       Pipeline::State state);
  63   scoped_ptr<MediaLogEvent> CreatePipelineErrorEvent(PipelineStatus error);
  64   scoped_ptr<MediaLogEvent> CreateVideoSizeSetEvent(
  65       size_t width, size_t height);
  66   scoped_ptr<MediaLogEvent> CreateBufferedExtentsChangedEvent(
  67       int64 start, int64 current, int64 end);
  68   scoped_ptr<MediaLogEvent> CreateMediaSourceErrorEvent(
  69       const std::string& error);
  70
  71  protected:
  72   friend class base::RefCountedThreadSafe<MediaLog>;
  73   virtual ~MediaLog();
  74
  75  private:
  76   // A unique (to this process) id for this MediaLog.
  77   int32 id_;
  78
  79   DISALLOW_COPY_AND_ASSIGN(MediaLog);
  80 };
  81
  82 }  // namespace media
  83
  84 #endif  // MEDIA_BASE_MEDIA_LOG_H_