// 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_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_
#define BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_

#include "base/base_export.h"
#include "base/macros.h"
#include "base/process/process_handle.h"
#include "base/trace_event/memory_dump_request_args.h"

namespace base {
namespace trace_event {

class ProcessMemoryDump;

// Args passed to OnMemoryDump(). This is to avoid rewriting all the subclasses
// in the codebase when extending the MemoryDumpProvider API.
struct MemoryDumpArgs {
  MemoryDumpLevelOfDetail level_of_detail;
};

// The contract interface that memory dump providers must implement.
class BASE_EXPORT MemoryDumpProvider {
 public:
  // Optional arguments for MemoryDumpManager::RegisterDumpProvider().
  struct Options {
    Options() : target_pid(kNullProcessId) {}
    explicit Options(ProcessId target_pid) : target_pid(target_pid) {}

    // If the dump provider generates dumps on behalf of another process,
    // |target_process| contains the pid of that process.
    // The default value is kNullProcessId, which means that the dump provider
    // generates dumps for the current process.
    ProcessId target_pid;
  };

  virtual ~MemoryDumpProvider() {}

  // Called by the MemoryDumpManager when generating memory dumps.
  // The |args| specify if the embedder should generate light/heavy dumps on
  // dump requests. The embedder should return true if the |pmd| was
  // successfully populated, false if something went wrong and the dump should
  // be considered invalid.
  // (Note, the MemoryDumpManager has a fail-safe logic which will disable the
  // MemoryDumpProvider for the entire trace session if it fails consistently).
  virtual bool OnMemoryDump(const MemoryDumpArgs& args,
                            ProcessMemoryDump* pmd) = 0;

  // Called by the MemoryDumpManager when an allocator should start or stop
  // collecting extensive allocation data, if supported.
  virtual void OnHeapProfilingEnabled(bool enabled) {}

 protected:
  MemoryDumpProvider() {}

  DISALLOW_COPY_AND_ASSIGN(MemoryDumpProvider);
};

}  // namespace trace_event
}  // namespace base

#endif  // BASE_TRACE_EVENT_MEMORY_DUMP_PROVIDER_H_
