// 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 NET_DNS_MOJO_HOST_RESOLVER_IMPL_H_
#define NET_DNS_MOJO_HOST_RESOLVER_IMPL_H_

#include <set>

#include "base/macros.h"
#include "base/threading/thread_checker.h"
#include "net/interfaces/host_resolver_service.mojom.h"

namespace net {

class HostResolver;

// This is the implementation of the HostResolver Mojo interface.
// Inbound Mojo requests are sent to the HostResolver passed into the
// constructor. When destroyed, any outstanding resolver requests are cancelled.
// If a request's HostResolverRequestClient is shut down, the associated
// resolver request is cancelled.
class MojoHostResolverImpl : public interfaces::HostResolver {
 public:
  // |resolver| is expected to outlive |this|.
  explicit MojoHostResolverImpl(net::HostResolver* resolver);
  ~MojoHostResolverImpl() override;

 private:
  class Job;

  // Removes |job| from the set of pending jobs, and deletes it.
  void DeleteJob(Job* job);

  // Overridden from net::interfaces::HostResolver:
  void Resolve(interfaces::HostResolverRequestInfoPtr request_info,
               interfaces::HostResolverRequestClientPtr client) override;

  // Resolver for resolving incoming requests. Not owned.
  net::HostResolver* resolver_;

  // All pending jobs, so they can be cancelled when this service is destroyed.
  // Owns all jobs.
  std::set<Job*> pending_jobs_;

  base::ThreadChecker thread_checker_;

  DISALLOW_COPY_AND_ASSIGN(MojoHostResolverImpl);
};

}  // namespace net

#endif  // NET_DNS_MOJO_HOST_RESOLVER_IMPL_H_