Trace category groups and category filter.

base/debug/trace_event_impl.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 #ifndef BASE_DEBUG_TRACE_EVENT_IMPL_H_
 #define BASE_DEBUG_TRACE_EVENT_IMPL_H_
 
 #include "build/build_config.h"
 
@@ skipping 158 matching lines @@
     // A subscribed trace-event occurred.
     EVENT_WATCH_NOTIFICATION = 1 << 1
   };
 
   static TraceLog* GetInstance();
 
   // Get set of known categories. This can change as new code paths are reached.
   // The known categories are inserted into |categories|.
   void GetKnownCategories(std::vector<std::string>* categories);
 
-  // Enable tracing for provided list of categories. If tracing is already
-  // enabled, this method does nothing -- changing categories during trace is
-  // not supported.
-  // If both included_categories and excluded_categories are empty,
-  //   all categories are traced.
-  // Else if included_categories is non-empty, only those are traced.
-  // Else if excluded_categories is non-empty, everything but those are traced.
+  // Enable tracing for provided list of category tags. If tracing is already
+  // enabled, this method does nothing -- changing category tags during trace
+  // is not supported.
+  // If both included_tag_patterns and excluded_tag_patterns are empty,
+  // all categories are traced.
+  // Else if included_tag_patterns is non-empty, only those categories with
+  // matching tags are traced.
+  // Else if excluded_tag_patterns is non-empty, everything but those
+  // categories with matching tags are traced.
   // Wildcards * and ? are supported (see MatchPattern in string_util.h).
-  void SetEnabled(const std::vector<std::string>& included_categories,
-                  const std::vector<std::string>& excluded_categories);
+  void SetEnabled(const std::vector<std::string>& included_tag_patterns,
+                  const std::vector<std::string>& excluded_tag_patterns);
 
-  // |categories| is a comma-delimited list of category wildcards.
-  // A category can have an optional '-' prefix to make it an excluded category.
+  // |tag_patterns| is a comma-delimited list of category tag wildcards.
+  // A tag pattern can have an optional '-' prefix to exclude categories
+  // with matching tags excluded.
+  //
   // All the same rules apply above, so for example, having both included and
-  // excluded categories in the same list would not be supported.
+  // excluded category tags in the same list would not be supported.
   //
   // Example: SetEnabled("test_MyTest*");
   // Example: SetEnabled("test_MyTest*,test_OtherStuff");
-  // Example: SetEnabled("-excluded_category1,-excluded_category2");
-  void SetEnabled(const std::string& categories);
+  // Example: SetEnabled("-excluded_category_tag1,-excluded_category_tag2");
+  void SetEnabled(const std::string& tag_patterns);
 
   // Retieves the categories set via a prior call to SetEnabled(). Only
   // meaningful if |IsEnabled()| is true.
   void GetEnabledTraceCategories(std::vector<std::string>* included_out,
                                  std::vector<std::string>* excluded_out);
 
   // Disable tracing for all categories.
   void SetDisabled();
   // Helper method to enable/disable tracing for all categories.
   void SetEnabled(bool enabled);
@@ skipping 34 matching lines @@
 
   // Flush all collected events to the given output callback. The callback will
   // be called one or more times with IPC-bite-size chunks. The string format is
   // undefined. Use TraceResultBuffer to convert one or more trace strings to
   // JSON.
   typedef base::Callback<void(const scoped_refptr<base::RefCountedString>&)>
       OutputCallback;
   void Flush(const OutputCallback& cb);
 
   // Called by TRACE_EVENT* macros, don't call this directly.
+  // The name parameter is a category name that can be made up of tags, for
+  // example: TRACE_EVENT0("renderer,webkit", "WebViewImpl::HandleInputEvent")
   static const unsigned char* GetCategoryEnabled(const char* name);
   static const char* GetCategoryName(const unsigned char* category_enabled);
 
   // Called by TRACE_EVENT* macros, don't call this directly.
   // If |copy| is set, |name|, |arg_name1| and |arg_name2| will be deep copied
   // into the event; see "Memory scoping note" and TRACE_EVENT_COPY_XXX above.
   void AddTraceEvent(char phase,
                     const unsigned char* category_enabled,
                     const char* name,
                     unsigned long long id,
@@ skipping 100 matching lines @@
   static void ApplyATraceEnabledFlag(unsigned char* category_enabled);
 #endif
 
   // TODO(nduca): switch to per-thread trace buffers to reduce thread
   // synchronization.
   // This lock protects TraceLog member accesses from arbitrary threads.
   Lock lock_;
   bool enabled_;
   NotificationCallback notification_callback_;
   std::vector<TraceEvent> logged_events_;
-  std::vector<std::string> included_categories_;
-  std::vector<std::string> excluded_categories_;
+  std::vector<std::string> included_tag_patterns_;
+  std::vector<std::string> excluded_tag_patterns_;
   bool dispatching_to_observer_list_;
   ObserverList<EnabledStateChangedObserver> enabled_state_observer_list_;
 
   base::hash_map<int, std::string> thread_names_;
 
   // XORed with TraceID to make it unlikely to collide with other processes.
   unsigned long long process_id_hash_;
 
   int process_id_;
 
   TimeDelta time_offset_;
 
   // Allow tests to wake up when certain events occur.
   const unsigned char* watch_category_;
   std::string watch_event_name_;
 
   DISALLOW_COPY_AND_ASSIGN(TraceLog);
 };
 
 }  // namespace debug
 }  // namespace base
 
 #endif  // BASE_DEBUG_TRACE_EVENT_IMPL_H_