Revert of [Tracing] V8 Tracing Controller

include/libplatform/v8-tracing.h

-// Copyright 2016 the V8 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.
-
-#ifndef V8_LIBPLATFORM_V8_TRACING_H_
-#define V8_LIBPLATFORM_V8_TRACING_H_
-
-#include <fstream>
-#include <memory>
-#include <vector>
-
-namespace v8 {
-namespace platform {
-namespace tracing {
-
-class TraceObject {
- public:
-  TraceObject() {}
-  void Initialize(char phase, const uint8_t* category_enabled_flag,
-                  const char* name, const char* scope, uint64_t id,
-                  uint64_t bind_id, int num_args, const char** arg_names,
-                  const uint8_t* arg_types, const uint64_t* arg_values,
-                  unsigned int flags);
-  void UpdateDuration();
-  void InitializeForTesting(char phase, const uint8_t* category_enabled_flag,
-                            const char* name, const char* scope, uint64_t id,
-                            uint64_t bind_id, int num_args,
-                            const char** arg_names, const uint8_t* arg_types,
-                            const uint64_t* arg_values, unsigned int flags,
-                            int pid, int tid, int64_t ts, int64_t tts,
-                            uint64_t duration, uint64_t cpu_duration);
-
-  int pid() const { return pid_; }
-  int tid() const { return tid_; }
-  char phase() const { return phase_; }
-  const uint8_t* category_enabled_flag() const {
-    return category_enabled_flag_;
-  }
-  const char* name() const { return name_; }
-  const char* scope() const { return scope_; }
-  uint64_t id() const { return id_; }
-  uint64_t bind_id() const { return bind_id_; }
-  unsigned int flags() const { return flags_; }
-  int64_t ts() { return ts_; }
-  int64_t tts() { return tts_; }
-  uint64_t duration() { return duration_; }
-  uint64_t cpu_duration() { return cpu_duration_; }
-
- private:
-  int pid_;
-  int tid_;
-  char phase_;
-  const char* name_;
-  const char* scope_;
-  const uint8_t* category_enabled_flag_;
-  uint64_t id_;
-  uint64_t bind_id_;
-  int num_args_;
-  unsigned int flags_;
-  int64_t ts_;
-  int64_t tts_;
-  uint64_t duration_;
-  uint64_t cpu_duration_;
-  // TODO(fmeawad): Add args support.
-
-  // Disallow copy and assign
-  TraceObject(const TraceObject&) = delete;
-  void operator=(const TraceObject&) = delete;
-};
-
-class TraceWriter {
- public:
-  TraceWriter() {}
-  virtual ~TraceWriter() {}
-  virtual void AppendTraceEvent(TraceObject* trace_event) = 0;
-  virtual void Flush() = 0;
-
-  static TraceWriter* CreateJSONTraceWriter(std::ostream& stream);
-
- private:
-  // Disallow copy and assign
-  TraceWriter(const TraceWriter&) = delete;
-  void operator=(const TraceWriter&) = delete;
-};
-
-class TraceBufferChunk {
- public:
-  explicit TraceBufferChunk(uint32_t seq);
-
-  void Reset(uint32_t new_seq);
-  bool IsFull() const { return next_free_ == kChunkSize; }
-  TraceObject* AddTraceEvent(size_t* event_index);
-  TraceObject* GetEventAt(size_t index) { return &chunk_[index]; }
-
-  uint32_t seq() const { return seq_; }
-  size_t size() const { return next_free_; }
-
-  static const size_t kChunkSize = 64;
-
- private:
-  size_t next_free_ = 0;
-  TraceObject chunk_[kChunkSize];
-  uint32_t seq_;
-
-  // Disallow copy and assign
-  TraceBufferChunk(const TraceBufferChunk&) = delete;
-  void operator=(const TraceBufferChunk&) = delete;
-};
-
-class TraceBuffer {
- public:
-  TraceBuffer() {}
-  virtual ~TraceBuffer() {}
-
-  virtual TraceObject* AddTraceEvent(uint64_t* handle) = 0;
-  virtual TraceObject* GetEventByHandle(uint64_t handle) = 0;
-  virtual bool Flush() = 0;
-
-  static const size_t kRingBufferChunks = 1024;
-
-  static TraceBuffer* CreateTraceBufferRingBuffer(size_t max_chunks,
-                                                  TraceWriter* trace_writer);
-
- private:
-  // Disallow copy and assign
-  TraceBuffer(const TraceBuffer&) = delete;
-  void operator=(const TraceBuffer&) = delete;
-};
-
-// Options determines how the trace buffer stores data.
-enum TraceRecordMode {
-  // Record until the trace buffer is full.
-  RECORD_UNTIL_FULL,
-
-  // Record until the user ends the trace. The trace buffer is a fixed size
-  // and we use it as a ring buffer during recording.
-  RECORD_CONTINUOUSLY,
-
-  // Record until the trace buffer is full, but with a huge buffer size.
-  RECORD_AS_MUCH_AS_POSSIBLE,
-
-  // Echo to console. Events are discarded.
-  ECHO_TO_CONSOLE,
-};
-
-class TraceConfig {
- public:
-  typedef std::vector<std::string> StringList;
-
-  TraceConfig()
-      : enable_sampling_(false),
-        enable_systrace_(false),
-        enable_argument_filter_(false) {}
-  TraceRecordMode GetTraceRecordMode() const { return record_mode_; }
-  bool IsSamplingEnabled() const { return enable_sampling_; }
-  bool IsSystraceEnabled() const { return enable_systrace_; }
-  bool IsArgumentFilterEnabled() const { return enable_argument_filter_; }
-
-  void SetTraceRecordMode(TraceRecordMode mode) { record_mode_ = mode; }
-  void EnableSampling() { enable_sampling_ = true; }
-  void EnableSystrace() { enable_systrace_ = true; }
-  void EnableArgumentFilter() { enable_argument_filter_ = true; }
-
-  void AddIncludedCategory(const char* included_category);
-  void AddExcludedCategory(const char* excluded_category);
-
-  bool IsCategoryGroupEnabled(const char* category_group) const;
-
- private:
-  TraceRecordMode record_mode_;
-  bool enable_sampling_ : 1;
-  bool enable_systrace_ : 1;
-  bool enable_argument_filter_ : 1;
-  StringList included_categories_;
-  StringList excluded_categories_;
-
-  // Disallow copy and assign
-  TraceConfig(const TraceConfig&) = delete;
-  void operator=(const TraceConfig&) = delete;
-};
-
-class TracingController {
- public:
-  enum Mode { DISABLED = 0, RECORDING_MODE };
-
-  // The pointer returned from GetCategoryGroupEnabledInternal() points to a
-  // value with zero or more of the following bits. Used in this class only.
-  // The TRACE_EVENT macros should only use the value as a bool.
-  // These values must be in sync with macro values in TraceEvent.h in Blink.
-  enum CategoryGroupEnabledFlags {
-    // Category group enabled for the recording mode.
-    ENABLED_FOR_RECORDING = 1 << 0,
-    // Category group enabled by SetEventCallbackEnabled().
-    ENABLED_FOR_EVENT_CALLBACK = 1 << 2,
-    // Category group enabled to export events to ETW.
-    ENABLED_FOR_ETW_EXPORT = 1 << 3
-  };
-
-  TracingController() {}
-  void Initialize(TraceBuffer* trace_buffer);
-  const uint8_t* GetCategoryGroupEnabled(const char* category_group);
-  static const char* GetCategoryGroupName(const uint8_t* category_enabled_flag);
-  uint64_t AddTraceEvent(char phase, const uint8_t* category_enabled_flag,
-                         const char* name, const char* scope, uint64_t id,
-                         uint64_t bind_id, int32_t num_args,
-                         const char** arg_names, const uint8_t* arg_types,
-                         const uint64_t* arg_values, unsigned int flags);
-  void UpdateTraceEventDuration(const uint8_t* category_enabled_flag,
-                                const char* name, uint64_t handle);
-
-  void StartTracing(TraceConfig* trace_config);
-  void StopTracing();
-
- private:
-  const uint8_t* GetCategoryGroupEnabledInternal(const char* category_group);
-  void UpdateCategoryGroupEnabledFlag(size_t category_index);
-  void UpdateCategoryGroupEnabledFlags();
-
-  std::unique_ptr<TraceBuffer> trace_buffer_;
-  std::unique_ptr<TraceConfig> trace_config_;
-  Mode mode_ = DISABLED;
-
-  // Disallow copy and assign
-  TracingController(const TracingController&) = delete;
-  void operator=(const TracingController&) = delete;
-};
-
-}  // namespace tracing
-}  // namespace platform
-}  // namespace v8
-
-#endif  // V8_LIBPLATFORM_V8_TRACING_H_