chrome/browser/extensions/api/mdns/dns_sd_registry.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_
   6 #define CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_
   7
   8 #include <map>
   9 #include <string>
  10 #include <utility>
  11 #include <vector>
  12
  13 #include "base/memory/linked_ptr.h"
  14 #include "base/memory/scoped_ptr.h"
  15 #include "base/observer_list.h"
  16 #include "chrome/browser/extensions/api/mdns/dns_sd_delegate.h"
  17
  18 namespace local_discovery {
  19 class ServiceDiscoverySharedClient;
  20 class ServiceDiscoveryClient;
  21 }
  22
  23 namespace extensions {
  24
  25 class DnsSdDeviceLister;
  26 class ServiceTypeData;
  27
  28 // Registry class for keeping track of discovered network services over DNS-SD.
  29 class DnsSdRegistry : public DnsSdDelegate {
  30  public:
  31   typedef std::vector<DnsSdService> DnsSdServiceList;
  32
  33   class DnsSdObserver {
  34    public:
  35     virtual void OnDnsSdEvent(const std::string& service_type,
  36                               const DnsSdServiceList& services) = 0;
  37
  38    protected:
  39     virtual ~DnsSdObserver() {}
  40   };
  41
  42   DnsSdRegistry();
  43   explicit DnsSdRegistry(local_discovery::ServiceDiscoverySharedClient* client);
  44   virtual ~DnsSdRegistry();
  45
  46   // Publishes the current device list for |service_type| to event listeners
  47   // whose event filter matches the service type.
  48   virtual void Publish(const std::string& service_type);
  49
  50   // Immediately issues a multicast DNS query for all service types of the
  51   // calling extension.
  52   virtual void ForceDiscovery();
  53
  54   // Observer registration for parties interested in discovery events.
  55   virtual void AddObserver(DnsSdObserver* observer);
  56   virtual void RemoveObserver(DnsSdObserver* observer);
  57
  58   // DNS-SD-related discovery functionality.
  59   virtual void RegisterDnsSdListener(const std::string& service_type);
  60   virtual void UnregisterDnsSdListener(const std::string& service_type);
  61
  62  protected:
  63   // Data class for managing all the resources and information related to a
  64   // particular service type.
  65   class ServiceTypeData {
  66    public:
  67     explicit ServiceTypeData(scoped_ptr<DnsSdDeviceLister> lister);
  68     virtual ~ServiceTypeData();
  69
  70     // Notify the data class of listeners so that it can be reference counted.
  71     void ListenerAdded();
  72     // Returns true if the last listener was removed.
  73     bool ListenerRemoved();
  74     int GetListenerCount();
  75
  76     // Immediately issues a multicast DNS query for the service type owned by
  77     // |this|.
  78     void ForceDiscovery();
  79
  80     // Methods for adding, updating or removing services for this service type.
  81     bool UpdateService(bool added, const DnsSdService& service);
  82     bool RemoveService(const std::string& service_name);
  83     // Called when the discovery service was restarted.
  84     // Clear the local cache and initiate rediscovery.
  85     bool ClearServices();
  86
  87     const DnsSdRegistry::DnsSdServiceList& GetServiceList();
  88
  89    private:
  90     int ref_count;
  91     scoped_ptr<DnsSdDeviceLister> lister_;
  92     DnsSdRegistry::DnsSdServiceList service_list_;
  93     DISALLOW_COPY_AND_ASSIGN(ServiceTypeData);
  94   };
  95
  96   // Maps service types to associated data such as listers and service lists.
  97   typedef std::map<std::string, linked_ptr<ServiceTypeData> >
  98       DnsSdServiceTypeDataMap;
  99
 100   virtual DnsSdDeviceLister* CreateDnsSdDeviceLister(
 101       DnsSdDelegate* delegate,
 102       const std::string& service_type,
 103       local_discovery::ServiceDiscoverySharedClient* discovery_client);
 104
 105   // DnsSdDelegate implementation:
 106   void ServiceChanged(const std::string& service_type,
 107                       bool added,
 108                       const DnsSdService& service) override;
 109   void ServiceRemoved(const std::string& service_type,
 110                       const std::string& service_name) override;
 111   void ServicesFlushed(const std::string& service_type) override;
 112
 113   DnsSdServiceTypeDataMap service_data_map_;
 114
 115  private:
 116   void DispatchApiEvent(const std::string& service_type);
 117   bool IsRegistered(const std::string& service_type);
 118
 119   scoped_refptr<local_discovery::ServiceDiscoverySharedClient>
 120       service_discovery_client_;
 121   base::ObserverList<DnsSdObserver> observers_;
 122
 123   DISALLOW_COPY_AND_ASSIGN(DnsSdRegistry);
 124 };
 125
 126 }  // namespace extensions
 127
 128 #endif  // CHROME_BROWSER_EXTENSIONS_API_MDNS_DNS_SD_REGISTRY_H_