Cache for mDNS records

net/dns/record_parsed.h

 // Copyright (c) 2013 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_RECORD_PARSED_H_
 #define NET_DNS_RECORD_PARSED_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
+#include "base/time.h"
 #include "net/base/net_export.h"
 
 namespace net {
 
 class DnsRecordParser;
 class RecordRdata;
 
 // Parsed record. This is a form of DnsResourceRecord where the rdata section
 // has been parsed into a data structure.
 class NET_EXPORT_PRIVATE RecordParsed {
  public:
   virtual ~RecordParsed();
 
   // All records are inherently immutable. Return a const pointer.
-  static scoped_ptr<const RecordParsed> CreateFrom(DnsRecordParser* parser);
+  static scoped_ptr<const RecordParsed> CreateFrom(DnsRecordParser* parser,
+                                                   base::Time time_created);
 
   const std::string& name() const { return name_; }
   uint16 type() const { return type_; }
   uint16 klass() const { return klass_; }
   uint32 ttl() const { return ttl_; }
 
+  base::Time time_created() const { return time_created_; }
+
   template <class T> const T* rdata() const {
     if (T::kType != type_)
       return NULL;
     return static_cast<const T*>(rdata_.get());
   }
 
+  // Check if two records have the same data. Ignores time_created and ttl.
+  // If |is_mdns| is true, ignore the top bit of the class
+  // (the cache flush bit).
+  bool IsEqual(const RecordParsed* other, bool is_mdns) const;
+
  private:
-  RecordParsed(const std::string& name, uint16 type, uint16 klass, uint32 ttl,
-               scoped_ptr<const RecordRdata> rdata);
+  RecordParsed(const std::string& name, uint16 type, uint16 klass,
+               uint32 ttl, scoped_ptr<const RecordRdata> rdata,
+               base::Time time_created);
 
   std::string name_;  // in dotted form
   const uint16 type_;
   const uint16 klass_;
   const uint32 ttl_;
 
   const scoped_ptr<const RecordRdata> rdata_;
 
-  DISALLOW_COPY_AND_ASSIGN(RecordParsed);
+  const base::Time time_created_;
 };
 
 }  // namespace net
 
 #endif  // NET_DNS_RECORD_PARSED_H_