Repo created

TMessagesProj/jni/voip/webrtc/base/profiler/stack_sampler.h

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+// Copyright 2015 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_PROFILER_STACK_SAMPLER_H_
+#define BASE_PROFILER_STACK_SAMPLER_H_
+
+#include <memory>
+
+#include "base/base_export.h"
+#include "base/macros.h"
+#include "base/profiler/sampling_profiler_thread_token.h"
+#include "base/threading/platform_thread.h"
+
+namespace base {
+
+class Unwinder;
+class ModuleCache;
+class ProfileBuilder;
+class StackBuffer;
+class StackSamplerTestDelegate;
+
+// StackSampler is an implementation detail of StackSamplingProfiler. It
+// abstracts the native implementation required to record a set of stack frames
+// for a given thread.
+class BASE_EXPORT StackSampler {
+ public:
+  virtual ~StackSampler();
+
+  // Creates a stack sampler that records samples for thread with
+  // |thread_token|. Returns null if this platform does not support stack
+  // sampling.
+  static std::unique_ptr<StackSampler> Create(
+      SamplingProfilerThreadToken thread_token,
+      ModuleCache* module_cache,
+      StackSamplerTestDelegate* test_delegate,
+      std::unique_ptr<Unwinder> native_unwinder = nullptr);
+
+  // Gets the required size of the stack buffer.
+  static size_t GetStackBufferSize();
+
+  // Creates an instance of the a stack buffer that can be used for calls to
+  // any StackSampler object.
+  static std::unique_ptr<StackBuffer> CreateStackBuffer();
+
+  // The following functions are all called on the SamplingThread (not the
+  // thread being sampled).
+
+  // Adds an auxiliary unwinder to handle additional, non-native-code unwind
+  // scenarios.
+  virtual void AddAuxUnwinder(std::unique_ptr<Unwinder> unwinder) = 0;
+
+  // Records a set of frames and returns them.
+  virtual void RecordStackFrames(StackBuffer* stackbuffer,
+                                 ProfileBuilder* profile_builder) = 0;
+
+ protected:
+  StackSampler();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(StackSampler);
+};
+
+// StackSamplerTestDelegate provides seams for test code to execute during stack
+// collection.
+class BASE_EXPORT StackSamplerTestDelegate {
+ public:
+  virtual ~StackSamplerTestDelegate();
+
+  // Called after copying the stack and resuming the target thread, but prior to
+  // walking the stack. Invoked on the SamplingThread.
+  virtual void OnPreStackWalk() = 0;
+
+ protected:
+  StackSamplerTestDelegate();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(StackSamplerTestDelegate);
+};
+
+}  // namespace base
+
+#endif  // BASE_PROFILER_STACK_SAMPLER_H_