xref: /aosp_15_r20/external/webrtc/rtc_base/event_tracer.h (revision d9f758449e529ab9291ac668be2861e7a55c2422)
1 /*
2  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 // This file defines the interface for event tracing in WebRTC.
12 //
13 // Event log handlers are set through SetupEventTracer(). User of this API will
14 // provide two function pointers to handle event tracing calls.
15 //
16 // * GetCategoryEnabledPtr
17 //   Event tracing system calls this function to determine if a particular
18 //   event category is enabled.
19 //
20 // * AddTraceEventPtr
21 //   Adds a tracing event. It is the user's responsibility to log the data
22 //   provided.
23 //
24 // Parameters for the above two functions are described in trace_event.h.
25 
26 #ifndef RTC_BASE_EVENT_TRACER_H_
27 #define RTC_BASE_EVENT_TRACER_H_
28 
29 #include <stdio.h>
30 
31 #include "absl/strings/string_view.h"
32 #include "rtc_base/system/rtc_export.h"
33 
34 namespace webrtc {
35 
36 typedef const unsigned char* (*GetCategoryEnabledPtr)(const char* name);
37 typedef void (*AddTraceEventPtr)(char phase,
38                                  const unsigned char* category_enabled,
39                                  const char* name,
40                                  unsigned long long id,
41                                  int num_args,
42                                  const char** arg_names,
43                                  const unsigned char* arg_types,
44                                  const unsigned long long* arg_values,
45                                  unsigned char flags);
46 
47 // User of WebRTC can call this method to setup event tracing.
48 //
49 // This method must be called before any WebRTC methods. Functions
50 // provided should be thread-safe.
51 void SetupEventTracer(GetCategoryEnabledPtr get_category_enabled_ptr,
52                       AddTraceEventPtr add_trace_event_ptr);
53 
54 // This class defines interface for the event tracing system to call
55 // internally. Do not call these methods directly.
56 class EventTracer {
57  public:
58   static const unsigned char* GetCategoryEnabled(const char* name);
59 
60   static void AddTraceEvent(char phase,
61                             const unsigned char* category_enabled,
62                             const char* name,
63                             unsigned long long id,
64                             int num_args,
65                             const char** arg_names,
66                             const unsigned char* arg_types,
67                             const unsigned long long* arg_values,
68                             unsigned char flags);
69 };
70 
71 }  // namespace webrtc
72 
73 namespace rtc {
74 namespace tracing {
75 // Set up internal event tracer.
76 RTC_EXPORT void SetupInternalTracer(bool enable_all_categories = true);
77 RTC_EXPORT bool StartInternalCapture(absl::string_view filename);
78 RTC_EXPORT void StartInternalCaptureToFile(FILE* file);
79 RTC_EXPORT void StopInternalCapture();
80 // Make sure we run this, this will tear down the internal tracing.
81 RTC_EXPORT void ShutdownInternalTracer();
82 }  // namespace tracing
83 }  // namespace rtc
84 
85 #endif  // RTC_BASE_EVENT_TRACER_H_
86