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

net/base/mock_host_resolver.h

-// Copyright (c) 2011 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_MOCK_HOST_RESOLVER_H_
-#define NET_BASE_MOCK_HOST_RESOLVER_H_
-
-#include <list>
-#include <map>
-
-#include "base/memory/weak_ptr.h"
-#include "base/synchronization/waitable_event.h"
-#include "base/threading/non_thread_safe.h"
-#include "net/base/host_resolver.h"
-#include "net/base/host_resolver_proc.h"
-
-namespace net {
-
-class HostCache;
-class RuleBasedHostResolverProc;
-
-// Fills |*addrlist| with a socket address for |host_list| which should be a
-// comma-separated list of IPv4 or IPv6 literal(s) without enclosing brackets.
-// If |canonical_name| is non-empty it is used as the DNS canonical name for
-// the host. Returns OK on success, ERR_UNEXPECTED otherwise.
-int ParseAddressList(const std::string& host_list,
-                     const std::string& canonical_name,
-                     AddressList* addrlist);
-
-// In most cases, it is important that unit tests avoid relying on making actual
-// DNS queries since the resulting tests can be flaky, especially if the network
-// is unreliable for some reason.  To simplify writing tests that avoid making
-// actual DNS queries, pass a MockHostResolver as the HostResolver dependency.
-// The socket addresses returned can be configured using the
-// RuleBasedHostResolverProc:
-//
-//   host_resolver->rules()->AddRule("foo.com", "1.2.3.4");
-//   host_resolver->rules()->AddRule("bar.com", "2.3.4.5");
-//
-// The above rules define a static mapping from hostnames to IP address
-// literals.  The first parameter to AddRule specifies a host pattern to match
-// against, and the second parameter indicates what value should be used to
-// replace the given hostname.  So, the following is also supported:
-//
-//   host_mapper->AddRule("*.com", "127.0.0.1");
-//
-// Replacement doesn't have to be string representing an IP address. It can
-// re-map one hostname to another as well.
-//
-// By default, MockHostResolvers include a single rule that maps all hosts to
-// 127.0.0.1.
-
-// Base class shared by MockHostResolver and MockCachingHostResolver.
-class MockHostResolverBase : public HostResolver,
-                             public base::SupportsWeakPtr<MockHostResolverBase>,
-                             public base::NonThreadSafe {
- public:
-  virtual ~MockHostResolverBase();
-
-  RuleBasedHostResolverProc* rules() { return rules_; }
-  void set_rules(RuleBasedHostResolverProc* rules) { rules_ = rules; }
-
-  // Controls whether resolutions complete synchronously or asynchronously.
-  void set_synchronous_mode(bool is_synchronous) {
-    synchronous_mode_ = is_synchronous;
-  }
-
-  // Asynchronous requests are automatically resolved by default.
-  // If set_ondemand_mode() is set then Resolve() returns IO_PENDING and
-  // ResolveAllPending() must be explicitly invoked to resolve all requests
-  // that are pending.
-  void set_ondemand_mode(bool is_ondemand) {
-    ondemand_mode_ = is_ondemand;
-  }
-
-  // HostResolver methods:
-  virtual int Resolve(const RequestInfo& info,
-                      AddressList* addresses,
-                      const CompletionCallback& callback,
-                      RequestHandle* out_req,
-                      const BoundNetLog& net_log) OVERRIDE;
-  virtual int ResolveFromCache(const RequestInfo& info,
-                               AddressList* addresses,
-                               const BoundNetLog& net_log) OVERRIDE;
-  virtual void CancelRequest(RequestHandle req) OVERRIDE;
-  virtual HostCache* GetHostCache() OVERRIDE;
-
-  // Resolves all pending requests. It is only valid to invoke this if
-  // set_ondemand_mode was set before. The requests are resolved asynchronously,
-  // after this call returns.
-  void ResolveAllPending();
-
-  // Returns true if there are pending requests that can be resolved by invoking
-  // ResolveAllPending().
-  bool has_pending_requests() const { return !requests_.empty(); }
-
-  // The number of times that Resolve() has been called.
-  size_t num_resolve() const {
-    return num_resolve_;
-  }
-
-  // The number of times that ResolveFromCache() has been called.
-  size_t num_resolve_from_cache() const {
-    return num_resolve_from_cache_;
-  }
-
- protected:
-  explicit MockHostResolverBase(bool use_caching);
-
- private:
-  struct Request;
-  typedef std::map<size_t, Request*> RequestMap;
-
-  // Resolve as IP or from |cache_| return cached error or
-  // DNS_CACHE_MISS if failed.
-  int ResolveFromIPLiteralOrCache(const RequestInfo& info,
-                                  AddressList* addresses);
-  // Resolve via |proc_|.
-  int ResolveProc(size_t id, const RequestInfo& info, AddressList* addresses);
-  // Resolve request stored in |requests_|. Pass rv to callback.
-  void ResolveNow(size_t id);
-
-  bool synchronous_mode_;
-  bool ondemand_mode_;
-  scoped_refptr<RuleBasedHostResolverProc> rules_;
-  scoped_ptr<HostCache> cache_;
-  RequestMap requests_;
-  size_t next_request_id_;
-
-  size_t num_resolve_;
-  size_t num_resolve_from_cache_;
-
-  DISALLOW_COPY_AND_ASSIGN(MockHostResolverBase);
-};
-
-class MockHostResolver : public MockHostResolverBase {
- public:
-  MockHostResolver() : MockHostResolverBase(false /*use_caching*/) {}
-  virtual ~MockHostResolver() {}
-};
-
-// Same as MockHostResolver, except internally it uses a host-cache.
-//
-// Note that tests are advised to use MockHostResolver instead, since it is
-// more predictable. (MockHostResolver also can be put into synchronous
-// operation mode in case that is what you needed from the caching version).
-class MockCachingHostResolver : public MockHostResolverBase {
- public:
-  MockCachingHostResolver() : MockHostResolverBase(true /*use_caching*/) {}
-  virtual ~MockCachingHostResolver() {}
-};
-
-// RuleBasedHostResolverProc applies a set of rules to map a host string to
-// a replacement host string. It then uses the system host resolver to return
-// a socket address. Generally the replacement should be an IPv4 literal so
-// there is no network dependency.
-class RuleBasedHostResolverProc : public HostResolverProc {
- public:
-  explicit RuleBasedHostResolverProc(HostResolverProc* previous);
-
-  // Any hostname matching the given pattern will be replaced with the given
-  // replacement value.  Usually, replacement should be an IP address literal.
-  void AddRule(const std::string& host_pattern,
-               const std::string& replacement);
-
-  // Same as AddRule(), but further restricts to |address_family|.
-  void AddRuleForAddressFamily(const std::string& host_pattern,
-                               AddressFamily address_family,
-                               const std::string& replacement);
-
-  // Same as AddRule(), but the replacement is expected to be an IPv4 or IPv6
-  // literal. This can be used in place of AddRule() to bypass the system's
-  // host resolver (the address list will be constructed manually).
-  // If |canonical_name| is non-empty, it is copied to the resulting AddressList
-  // but does not impact DNS resolution.
-  // |ip_literal| can be a single IP address like "192.168.1.1" or a comma
-  // separated list of IP addresses, like "::1,192:168.1.2".
-  void AddIPLiteralRule(const std::string& host_pattern,
-                        const std::string& ip_literal,
-                        const std::string& canonical_name);
-
-  void AddRuleWithLatency(const std::string& host_pattern,
-                          const std::string& replacement,
-                          int latency_ms);
-
-  // Make sure that |host| will not be re-mapped or even processed by underlying
-  // host resolver procedures. It can also be a pattern.
-  void AllowDirectLookup(const std::string& host);
-
-  // Simulate a lookup failure for |host| (it also can be a pattern).
-  void AddSimulatedFailure(const std::string& host);
-
-  // Deletes all the rules that have been added.
-  void ClearRules();
-
-  // HostResolverProc methods:
-  virtual int Resolve(const std::string& host,
-                      AddressFamily address_family,
-                      HostResolverFlags host_resolver_flags,
-                      AddressList* addrlist,
-                      int* os_error) OVERRIDE;
-
- private:
-  struct Rule;
-  typedef std::list<Rule> RuleList;
-
-  virtual ~RuleBasedHostResolverProc();
-
-  RuleList rules_;
-};
-
-// Create rules that map all requests to localhost.
-RuleBasedHostResolverProc* CreateCatchAllHostResolverProc();
-
-// HangingHostResolver never completes its |Resolve| request.
-class HangingHostResolver : public HostResolver {
- public:
-  virtual int Resolve(const RequestInfo& info,
-                      AddressList* addresses,
-                      const CompletionCallback& callback,
-                      RequestHandle* out_req,
-                      const BoundNetLog& net_log) OVERRIDE;
-  virtual int ResolveFromCache(const RequestInfo& info,
-                               AddressList* addresses,
-                               const BoundNetLog& net_log) OVERRIDE;
-  virtual void CancelRequest(RequestHandle req) OVERRIDE {}
-};
-
-// This class sets the default HostResolverProc for a particular scope.  The
-// chain of resolver procs starting at |proc| is placed in front of any existing
-// default resolver proc(s).  This means that if multiple
-// ScopedDefaultHostResolverProcs are declared, then resolving will start with
-// the procs given to the last-allocated one, then fall back to the procs given
-// to the previously-allocated one, and so forth.
-//
-// NOTE: Only use this as a catch-all safety net. Individual tests should use
-// MockHostResolver.
-class ScopedDefaultHostResolverProc {
- public:
-  ScopedDefaultHostResolverProc();
-  explicit ScopedDefaultHostResolverProc(HostResolverProc* proc);
-
-  ~ScopedDefaultHostResolverProc();
-
-  void Init(HostResolverProc* proc);
-
- private:
-  scoped_refptr<HostResolverProc> current_proc_;
-  scoped_refptr<HostResolverProc> previous_proc_;
-};
-
-}  // namespace net
-
-#endif  // NET_BASE_MOCK_HOST_RESOLVER_H_