[net] HostResolverImpl + DnsTransaction + DnsConfigService = Asynchronous DNS ready for experiments.

net/dns/async_host_resolver.h

Index: net/dns/async_host_resolver.h
diff --git a/net/dns/async_host_resolver.h b/net/dns/async_host_resolver.h
deleted file mode 100644
index 23d98082162c04db457ec5a5f23d632fd7ffff83..0000000000000000000000000000000000000000
--- a/net/dns/async_host_resolver.h
+++ /dev/null
@@ -1,138 +0,0 @@
-// Copyright (c) 2012 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_ASYNC_HOST_RESOLVER_H_
-#define NET_DNS_ASYNC_HOST_RESOLVER_H_
-#pragma once
-
-#include <list>
-#include <map>
-#include <string>
-#include <utility>
-
-#include "base/threading/non_thread_safe.h"
-#include "net/base/address_family.h"
-#include "net/base/host_cache.h"
-#include "net/base/host_resolver.h"
-#include "net/base/ip_endpoint.h"
-#include "net/base/net_log.h"
-#include "net/dns/dns_transaction.h"
-
-namespace net {
-
-class NET_EXPORT AsyncHostResolver
-    : public HostResolver,
-      NON_EXPORTED_BASE(public base::NonThreadSafe) {
- public:
-  AsyncHostResolver(size_t max_dns_requests,
-                    size_t max_pending_requests,
-                    HostCache* cache,
-                    scoped_ptr<DnsTransactionFactory> client,
-                    NetLog* net_log);
-  virtual ~AsyncHostResolver();
-
-  // HostResolver interface
-  virtual int Resolve(const RequestInfo& info,
-                      AddressList* addresses,
-                      const CompletionCallback& callback,
-                      RequestHandle* out_req,
-                      const BoundNetLog& source_net_log) OVERRIDE;
-  virtual int ResolveFromCache(const RequestInfo& info,
-                               AddressList* addresses,
-                               const BoundNetLog& source_net_log) OVERRIDE;
-  virtual void CancelRequest(RequestHandle req_handle) OVERRIDE;
-  virtual void SetDefaultAddressFamily(AddressFamily address_family) OVERRIDE;
-  virtual AddressFamily GetDefaultAddressFamily() const OVERRIDE;
-  virtual HostCache* GetHostCache() OVERRIDE;
-
-  void OnDnsTransactionComplete(DnsTransaction* transaction,
-                                int result,
-                                const DnsResponse* response);
-
- private:
-  FRIEND_TEST_ALL_PREFIXES(AsyncHostResolverTest, QueuedLookup);
-  FRIEND_TEST_ALL_PREFIXES(AsyncHostResolverTest, CancelPendingLookup);
-  FRIEND_TEST_ALL_PREFIXES(AsyncHostResolverTest,
-                           ResolverDestructionCancelsLookups);
-  FRIEND_TEST_ALL_PREFIXES(AsyncHostResolverTest,
-                           OverflowQueueWithLowPriorityLookup);
-  FRIEND_TEST_ALL_PREFIXES(AsyncHostResolverTest,
-                           OverflowQueueWithHighPriorityLookup);
-
-  class Request;
-
-  typedef std::pair<std::string, uint16> Key;
-  typedef std::list<Request*> RequestList;
-  typedef std::list<const DnsTransaction*> DnsTransactionList;
-  typedef std::map<Key, RequestList> KeyRequestListMap;
-
-  // Create a new request for the incoming Resolve() call.
-  Request* CreateNewRequest(const RequestInfo& info,
-                            const CompletionCallback& callback,
-                            AddressList* addresses,
-                            const BoundNetLog& source_net_log);
-
-  // Called when a request has just been started.
-  void OnStart(Request* request);
-
-  // Called when a request has just completed (before its callback is run).
-  void OnFinish(Request* request, int result);
-
-  // Called when a request has been cancelled.
-  void OnCancel(Request* request);
-
-  // If there is an in-progress transaction for Request->key(), this will
-  // attach |request| to the respective list.
-  bool AttachToRequestList(Request* request);
-
-  // Will start a new DNS request for |request|, will insert a new key in
-  // |requestlist_map_| and append |request| to the respective list.
-  int StartNewDnsRequestFor(Request* request);
-
-  // Will enqueue |request| in |pending_requests_|.
-  int Enqueue(Request* request);
-
-  // A helper used by Enqueue to insert |request| into |pending_requests_|.
-  Request* Insert(Request* request);
-
-  // Returns the number of pending requests.
-  size_t GetNumPending() const;
-
-  // Removes and returns a pointer to the lowest/highest priority request
-  // from |pending_requests_|.
-  Request* RemoveLowest();
-  Request* RemoveHighest();
-
-  // Once a transaction has completed, called to start a new transaction if
-  // there are pending requests.
-  void ProcessPending();
-
-  // Maximum number of concurrent DNS transactions.
-  size_t max_dns_transactions_;
-
-  // List of current DNS transactions.
-  DnsTransactionList dns_transactions_;
-
-  // A map from Key to a list of requests waiting for the Key to resolve.
-  KeyRequestListMap requestlist_map_;
-
-  // Maximum number of pending requests.
-  size_t max_pending_requests_;
-
-  // Queues based on priority for putting pending requests.
-  RequestList pending_requests_[NUM_PRIORITIES];
-
-  // Cache of host resolution results.
-  scoped_ptr<HostCache> cache_;
-
-  scoped_ptr<DnsTransactionFactory> client_;
-
-  NetLog* net_log_;
-
-  DISALLOW_COPY_AND_ASSIGN(AsyncHostResolver);
-};
-
-}  // namespace net
-
-#endif  // NET_DNS_ASYNC_HOST_RESOLVER_H_