1 // Copyright 2012 The Chromium Authors 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 NET_DNS_DNS_SESSION_H_ 6 #define NET_DNS_DNS_SESSION_H_ 7 8 #include <stdint.h> 9 10 #include "base/memory/raw_ptr.h" 11 #include "base/memory/ref_counted.h" 12 #include "base/memory/weak_ptr.h" 13 #include "net/base/net_export.h" 14 #include "net/base/rand_callback.h" 15 #include "net/dns/dns_config.h" 16 #include "net/dns/dns_udp_tracker.h" 17 18 namespace net { 19 20 class NetLog; 21 22 // Session parameters and state shared between DnsTransactions for a specific 23 // instance/version of a DnsConfig. Also may be used as a key handle for 24 // per-session state stored elsewhere, e.g. in ResolveContext. A new DnsSession 25 // should be created for each new DnsConfig for DnsTransactions to be based on 26 // that new configuration. 27 // 28 // Ref-counted so that DnsTransactions can keep working in absence of 29 // DnsClient or continue operating on the same session after DnsClient has moved 30 // to a new DnsConfig/DnsSession. 31 class NET_EXPORT_PRIVATE DnsSession : public base::RefCounted<DnsSession> { 32 public: 33 typedef base::RepeatingCallback<int()> RandCallback; 34 35 DnsSession(const DnsConfig& config, 36 const RandIntCallback& rand_int_callback, 37 NetLog* net_log); 38 39 DnsSession(const DnsSession&) = delete; 40 DnsSession& operator=(const DnsSession&) = delete; 41 config()42 const DnsConfig& config() const { return config_; } udp_tracker()43 DnsUdpTracker* udp_tracker() { return &udp_tracker_; } net_log()44 NetLog* net_log() const { return net_log_; } 45 46 // Return the next random query ID. 47 uint16_t NextQueryId() const; 48 GetWeakPtr()49 base::WeakPtr<DnsSession> GetWeakPtr() { 50 return weak_ptr_factory_.GetWeakPtr(); 51 } 52 GetWeakPtr()53 base::WeakPtr<const DnsSession> GetWeakPtr() const { 54 return weak_ptr_factory_.GetWeakPtr(); 55 } 56 57 void InvalidateWeakPtrsForTesting(); 58 59 private: 60 friend class base::RefCounted<DnsSession>; 61 62 ~DnsSession(); 63 64 const DnsConfig config_; 65 DnsUdpTracker udp_tracker_; 66 RandCallback rand_callback_; 67 raw_ptr<NetLog> net_log_; 68 69 mutable base::WeakPtrFactory<DnsSession> weak_ptr_factory_{this}; 70 }; 71 72 } // namespace net 73 74 #endif // NET_DNS_DNS_SESSION_H_ 75