net: move host_resolver files from net/base to net/dns

net/base/host_resolver_impl.h

Index: net/base/host_resolver_impl.h
diff --git a/net/base/host_resolver_impl.h b/net/base/host_resolver_impl.h
deleted file mode 100644
index 29a6d67731f78e321be03c8da51f955bbee2646c..0000000000000000000000000000000000000000
--- a/net/base/host_resolver_impl.h
+++ /dev/null
@@ -1,287 +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_BASE_HOST_RESOLVER_IMPL_H_
-#define NET_BASE_HOST_RESOLVER_IMPL_H_
-
-#include <map>
-
-#include "base/basictypes.h"
-#include "base/gtest_prod_util.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/scoped_vector.h"
-#include "base/memory/weak_ptr.h"
-#include "base/threading/non_thread_safe.h"
-#include "base/time.h"
-#include "net/base/capturing_net_log.h"
-#include "net/base/host_cache.h"
-#include "net/base/host_resolver.h"
-#include "net/base/host_resolver_proc.h"
-#include "net/base/net_export.h"
-#include "net/base/network_change_notifier.h"
-#include "net/base/prioritized_dispatcher.h"
-
-namespace net {
-
-class BoundNetLog;
-class DnsClient;
-class NetLog;
-
-// For each hostname that is requested, HostResolver creates a
-// HostResolverImpl::Job. When this job gets dispatched it creates a ProcTask
-// which runs the given HostResolverProc on a WorkerPool thread. If requests for
-// that same host are made during the job's lifetime, they are attached to the
-// existing job rather than creating a new one. This avoids doing parallel
-// resolves for the same host.
-//
-// The way these classes fit together is illustrated by:
-//
-//
-//            +----------- HostResolverImpl -------------+
-//            |                    |                     |
-//           Job                  Job                   Job
-//    (for host1, fam1)    (for host2, fam2)     (for hostx, famx)
-//       /    |   |            /   |   |             /   |   |
-//   Request ... Request  Request ... Request   Request ... Request
-//  (port1)     (port2)  (port3)      (port4)  (port5)      (portX)
-//
-// When a HostResolverImpl::Job finishes, the callbacks of each waiting request
-// are run on the origin thread.
-//
-// Thread safety: This class is not threadsafe, and must only be called
-// from one thread!
-//
-// The HostResolverImpl enforces limits on the maximum number of concurrent
-// threads using PrioritizedDispatcher::Limits.
-//
-// Jobs are ordered in the queue based on their priority and order of arrival.
-class NET_EXPORT HostResolverImpl
-    : public HostResolver,
-      NON_EXPORTED_BASE(public base::NonThreadSafe),
-      public NetworkChangeNotifier::IPAddressObserver,
-      public NetworkChangeNotifier::DNSObserver {
- public:
-  // Parameters for ProcTask which resolves hostnames using HostResolveProc.
-  //
-  // |resolver_proc| is used to perform the actual resolves; it must be
-  // thread-safe since it is run from multiple worker threads. If
-  // |resolver_proc| is NULL then the default host resolver procedure is
-  // used (which is SystemHostResolverProc except if overridden).
-  //
-  // For each attempt, we could start another attempt if host is not resolved
-  // within |unresponsive_delay| time. We keep attempting to resolve the host
-  // for |max_retry_attempts|. For every retry attempt, we grow the
-  // |unresponsive_delay| by the |retry_factor| amount (that is retry interval
-  // is multiplied by the retry factor each time). Once we have retried
-  // |max_retry_attempts|, we give up on additional attempts.
-  //
-  struct NET_EXPORT_PRIVATE ProcTaskParams {
-    // Sets up defaults.
-    ProcTaskParams(HostResolverProc* resolver_proc, size_t max_retry_attempts);
-
-    ~ProcTaskParams();
-
-    // The procedure to use for resolving host names. This will be NULL, except
-    // in the case of unit-tests which inject custom host resolving behaviors.
-    scoped_refptr<HostResolverProc> resolver_proc;
-
-    // Maximum number retry attempts to resolve the hostname.
-    // Pass HostResolver::kDefaultRetryAttempts to choose a default value.
-    size_t max_retry_attempts;
-
-    // This is the limit after which we make another attempt to resolve the host
-    // if the worker thread has not responded yet.
-    base::TimeDelta unresponsive_delay;
-
-    // Factor to grow |unresponsive_delay| when we re-re-try.
-    uint32 retry_factor;
-  };
-
-  // Creates a HostResolver that first uses the local cache |cache|, and then
-  // falls back to |proc_params.resolver_proc|.
-  //
-  // If |cache| is NULL, then no caching is used. Otherwise we take
-  // ownership of the |cache| pointer, and will free it during destruction.
-  //
-  // |job_limits| specifies the maximum number of jobs that the resolver will
-  // run at once. This upper-bounds the total number of outstanding
-  // DNS transactions (not counting retransmissions and retries).
-  //
-  // |net_log| must remain valid for the life of the HostResolverImpl.
-  HostResolverImpl(scoped_ptr<HostCache> cache,
-                   const PrioritizedDispatcher::Limits& job_limits,
-                   const ProcTaskParams& proc_params,
-                   NetLog* net_log);
-
-  // If any completion callbacks are pending when the resolver is destroyed,
-  // the host resolutions are cancelled, and the completion callbacks will not
-  // be called.
-  virtual ~HostResolverImpl();
-
-  // Configures maximum number of Jobs in the queue. Exposed for testing.
-  // Only allowed when the queue is empty.
-  void SetMaxQueuedJobs(size_t value);
-
-  // Set the DnsClient to be used for resolution. In case of failure, the
-  // HostResolverProc from ProcTaskParams will be queried. If the DnsClient is
-  // not pre-configured with a valid DnsConfig, a new config is fetched from
-  // NetworkChangeNotifier.
-  void SetDnsClient(scoped_ptr<DnsClient> dns_client);
-
-  // HostResolver methods:
-  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) OVERRIDE;
-  virtual void SetDefaultAddressFamily(AddressFamily address_family) OVERRIDE;
-  virtual AddressFamily GetDefaultAddressFamily() const OVERRIDE;
-  virtual void ProbeIPv6Support() OVERRIDE;
-  virtual void SetDnsClientEnabled(bool enabled) OVERRIDE;
-  virtual HostCache* GetHostCache() OVERRIDE;
-  virtual base::Value* GetDnsConfigAsValue() const OVERRIDE;
-
- private:
-  friend class HostResolverImplTest;
-  class Job;
-  class ProcTask;
-  class IPv6ProbeJob;
-  class LoopbackProbeJob;
-  class DnsTask;
-  class Request;
-  typedef HostCache::Key Key;
-  typedef std::map<Key, Job*> JobMap;
-  typedef ScopedVector<Request> RequestsList;
-
-  // Helper used by |Resolve()| and |ResolveFromCache()|.  Performs IP
-  // literal, cache and HOSTS lookup (if enabled), returns OK if successful,
-  // ERR_NAME_NOT_RESOLVED if either hostname is invalid or IP literal is
-  // incompatible, ERR_DNS_CACHE_MISS if entry was not found in cache and HOSTS.
-  int ResolveHelper(const Key& key,
-                    const RequestInfo& info,
-                    AddressList* addresses,
-                    const BoundNetLog& request_net_log);
-
-  // Tries to resolve |key| as an IP, returns true and sets |net_error| if
-  // succeeds, returns false otherwise.
-  bool ResolveAsIP(const Key& key,
-                   const RequestInfo& info,
-                   int* net_error,
-                   AddressList* addresses);
-
-  // If |key| is not found in cache returns false, otherwise returns
-  // true, sets |net_error| to the cached error code and fills |addresses|
-  // if it is a positive entry.
-  bool ServeFromCache(const Key& key,
-                      const RequestInfo& info,
-                      int* net_error,
-                      AddressList* addresses);
-
-  // If we have a DnsClient with a valid DnsConfig, and |key| is found in the
-  // HOSTS file, returns true and fills |addresses|. Otherwise returns false.
-  bool ServeFromHosts(const Key& key,
-                      const RequestInfo& info,
-                      AddressList* addresses);
-
-  // Callback from IPv6 probe activity.
-  void IPv6ProbeSetDefaultAddressFamily(AddressFamily address_family);
-
-  // Callback from HaveOnlyLoopbackAddresses probe.
-  void SetHaveOnlyLoopbackAddresses(bool result);
-
-  // Returns the (hostname, address_family) key to use for |info|, choosing an
-  // "effective" address family by inheriting the resolver's default address
-  // family when the request leaves it unspecified.
-  Key GetEffectiveKeyForRequest(const RequestInfo& info) const;
-
-  // Records the result in cache if cache is present.
-  void CacheResult(const Key& key,
-                   const HostCache::Entry& entry,
-                   base::TimeDelta ttl);
-
-  // Removes |job| from |jobs_|, only if it exists.
-  void RemoveJob(Job* job);
-
-  // Aborts all in progress jobs with ERR_NETWORK_CHANGED and notifies their
-  // requests. Might start new jobs.
-  void AbortAllInProgressJobs();
-
-  // Attempts to serve each Job in |jobs_| from the HOSTS file if we have
-  // a DnsClient with a valid DnsConfig.
-  void TryServingAllJobsFromHosts();
-
-  // NetworkChangeNotifier::IPAddressObserver:
-  virtual void OnIPAddressChanged() OVERRIDE;
-
-  // NetworkChangeNotifier::DNSObserver:
-  virtual void OnDNSChanged() OVERRIDE;
-
-  // True if have a DnsClient with a valid DnsConfig.
-  bool HaveDnsConfig() const;
-
-  // Called when a host name is successfully resolved and DnsTask was run on it
-  // and resulted in |net_error|.
-  void OnDnsTaskResolve(int net_error);
-
-  // Allows the tests to catch slots leaking out of the dispatcher.
-  size_t num_running_jobs_for_tests() const {
-    return dispatcher_.num_running_jobs();
-  }
-
-  // Cache of host resolution results.
-  scoped_ptr<HostCache> cache_;
-
-  // Map from HostCache::Key to a Job.
-  JobMap jobs_;
-
-  // Starts Jobs according to their priority and the configured limits.
-  PrioritizedDispatcher dispatcher_;
-
-  // Limit on the maximum number of jobs queued in |dispatcher_|.
-  size_t max_queued_jobs_;
-
-  // Parameters for ProcTask.
-  ProcTaskParams proc_params_;
-
-  NetLog* net_log_;
-
-  // Address family to use when the request doesn't specify one.
-  AddressFamily default_address_family_;
-
-  base::WeakPtrFactory<HostResolverImpl> weak_ptr_factory_;
-
-  base::WeakPtrFactory<HostResolverImpl> probe_weak_ptr_factory_;
-
-  // If present, used by DnsTask and ServeFromHosts to resolve requests.
-  scoped_ptr<DnsClient> dns_client_;
-
-  // True if received valid config from |dns_config_service_|. Temporary, used
-  // to measure performance of DnsConfigService: http://crbug.com/125599
-  bool received_dns_config_;
-
-  // Number of consecutive failures of DnsTask, counted when fallback succeeds.
-  unsigned num_dns_failures_;
-
-  // Indicate if probing is done after each network change event to set address
-  // family. When false, explicit setting of address family is used and results
-  // of the IPv6 probe job are ignored.
-  bool ipv6_probe_monitoring_;
-
-  // True iff ProcTask has successfully resolved a hostname known to have IPv6
-  // addresses using ADDRESS_FAMILY_UNSPECIFIED. Reset on IP address change.
-  bool resolved_known_ipv6_hostname_;
-
-  // Any resolver flags that should be added to a request by default.
-  HostResolverFlags additional_resolver_flags_;
-
-  DISALLOW_COPY_AND_ASSIGN(HostResolverImpl);
-};
-
-}  // namespace net
-
-#endif  // NET_BASE_HOST_RESOLVER_IMPL_H_