mojo/common/strong_binding_set.h

// Copyright 2014 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 MOJO_COMMON_STRONG_BINDING_SET_H_
#define MOJO_COMMON_STRONG_BINDING_SET_H_

#include <algorithm>
#include <memory>
#include <vector>

#include "base/logging.h"
#include "base/macros.h"
#include "mojo/public/cpp/bindings/binding.h"

namespace mojo {

// Use this class to manage a set of strong bindings each of which is
// owned by the pipe it is bound to.  The set takes ownership of the
// interfaces and will delete them when the bindings are closed.
template <typename Interface>
class StrongBindingSet {
 public:
  StrongBindingSet() {}
  ~StrongBindingSet() { CloseAllBindings(); }

  // Adds a binding to the list and arranges for it to be removed when
  // a connection error occurs.  Takes ownership of |impl|, which
  // will be deleted when the binding is closed.
  void AddBinding(Interface* impl, InterfaceRequest<Interface> request) {
    bindings_.emplace_back(new Binding<Interface>(impl, request.Pass()));
    auto* binding = bindings_.back().get();
    // Set the connection error handler for the newly added Binding to be a
    // function that will erase it from the vector.
    binding->set_connection_error_handler([this, binding]() {
      auto it =
          std::find_if(bindings_.begin(), bindings_.end(),
                       [binding](const std::unique_ptr<Binding<Interface>>& b) {
                         return (b.get() == binding);
                       });
      DCHECK(it != bindings_.end());
      delete binding->impl();
      bindings_.erase(it);
    });
  }

  // Removes all bindings for the specified interface implementation.
  // The implementation object is not destroyed.
  void RemoveBindings(Interface* impl) {
    bindings_.erase(
        std::remove_if(bindings_.begin(), bindings_.end(),
                       [impl](const std::unique_ptr<Binding<Interface>>& b) {
                         return (b->impl() == impl);
                       }));
  }

  // Closes all bindings and deletes their associated interfaces.
  void CloseAllBindings() {
    for (auto it = bindings_.begin(); it != bindings_.end(); ++it) {
      delete (*it)->impl();
    }
    bindings_.clear();
  }

  size_t size() const { return bindings_.size(); }

 private:
  std::vector<std::unique_ptr<Binding<Interface>>> bindings_;

  DISALLOW_COPY_AND_ASSIGN(StrongBindingSet);
};

}  // namespace mojo

#endif  // MOJO_COMMON_STRONG_BINDING_SET_H_