zircon/system/ulib/trace-provider/provider_impl.h

// Copyright 2017 The Fuchsia 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 ZIRCON_SYSTEM_ULIB_TRACE_PROVIDER_PROVIDER_IMPL_H_
#define ZIRCON_SYSTEM_ULIB_TRACE_PROVIDER_PROVIDER_IMPL_H_

#include <string>
#include <vector>

#include <lib/async/cpp/wait.h>
#include <lib/trace-engine/handler.h>
#include <lib/trace-engine/types.h>
#include <lib/trace-provider/provider.h>
#include <lib/zx/channel.h>
#include <lib/zx/fifo.h>
#include <lib/zx/time.h>
#include <lib/zx/vmo.h>

// Provide a definition for the opaque type declared in provider.h.
struct trace_provider {};

namespace trace {
namespace internal {

class TraceProviderImpl final : public trace_provider_t {
 public:
  TraceProviderImpl(async_dispatcher_t* dispatcher, zx::channel channel);
  ~TraceProviderImpl();

  async_dispatcher_t* dispatcher() const { return dispatcher_; }

 private:
  class Connection final {
   public:
    Connection(TraceProviderImpl* impl, zx::channel channel);
    ~Connection();

   private:
    void Handle(async_dispatcher_t* dispatcher, async::WaitBase* wait, zx_status_t status,
                const zx_packet_signal_t* signal);

    bool ReadMessage();
    bool DecodeAndDispatch(uint8_t* buffer, uint32_t num_bytes, zx_handle_t* handles,
                           uint32_t num_handles);
    void Close();

    TraceProviderImpl* const impl_;
    zx::channel channel_;
    async::WaitMethod<Connection, &Connection::Handle> wait_;
  };

  void Initialize(trace_buffering_mode_t buffering_mode, zx::vmo buffer, zx::fifo fifo,
                  std::vector<std::string> categories);
  void Start(trace_start_mode_t start_mode, std::vector<std::string> additional_categories);

  void Stop();
  void Terminate();

  void OnStopped();
  void OnTerminated();
  void OnClose();

  async_dispatcher_t* const dispatcher_;
  Connection connection_;

  TraceProviderImpl(const TraceProviderImpl&) = delete;
  TraceProviderImpl(TraceProviderImpl&&) = delete;
  TraceProviderImpl& operator=(const TraceProviderImpl&) = delete;
  TraceProviderImpl& operator=(TraceProviderImpl&&) = delete;
};

}  // namespace internal
}  // namespace trace

#endif  // ZIRCON_SYSTEM_ULIB_TRACE_PROVIDER_PROVIDER_IMPL_H_