net/dns/host_resolver_impl_unittest.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/dns/host_resolver_impl.h"
   6
   7 #include <algorithm>
   8 #include <string>
   9
  10 #include "base/bind.h"
  11 #include "base/bind_helpers.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/scoped_vector.h"
  14 #include "base/message_loop/message_loop.h"
  15 #include "base/run_loop.h"
  16 #include "base/strings/string_util.h"
  17 #include "base/strings/stringprintf.h"
  18 #include "base/synchronization/condition_variable.h"
  19 #include "base/synchronization/lock.h"
  20 #include "base/test/test_timeouts.h"
  21 #include "base/time/time.h"
  22 #include "net/base/address_list.h"
  23 #include "net/base/net_errors.h"
  24 #include "net/base/net_util.h"
  25 #include "net/dns/dns_client.h"
  26 #include "net/dns/dns_test_util.h"
  27 #include "net/dns/mock_host_resolver.h"
  28 #include "testing/gtest/include/gtest/gtest.h"
  29
  30 namespace net {
  31
  32 namespace {
  33
  34 const size_t kMaxJobs = 10u;
  35 const size_t kMaxRetryAttempts = 4u;
  36
  37 HostResolver::Options DefaultOptions() {
  38   HostResolver::Options options;
  39   options.max_concurrent_resolves = kMaxJobs;
  40   options.max_retry_attempts = kMaxRetryAttempts;
  41   options.enable_caching = true;
  42   return options;
  43 }
  44
  45 HostResolverImpl::ProcTaskParams DefaultParams(
  46     HostResolverProc* resolver_proc) {
  47   return HostResolverImpl::ProcTaskParams(resolver_proc, kMaxRetryAttempts);
  48 }
  49
  50 // A HostResolverProc that pushes each host mapped into a list and allows
  51 // waiting for a specific number of requests. Unlike RuleBasedHostResolverProc
  52 // it never calls SystemHostResolverCall. By default resolves all hostnames to
  53 // "127.0.0.1". After AddRule(), it resolves only names explicitly specified.
  54 class MockHostResolverProc : public HostResolverProc {
  55  public:
  56   struct ResolveKey {
  57     ResolveKey(const std::string& hostname, AddressFamily address_family)
  58         : hostname(hostname), address_family(address_family) {}
  59     bool operator<(const ResolveKey& other) const {
  60       return address_family < other.address_family ||
  61           (address_family == other.address_family && hostname < other.hostname);
  62     }
  63     std::string hostname;
  64     AddressFamily address_family;
  65   };
  66
  67   typedef std::vector<ResolveKey> CaptureList;
  68
  69   MockHostResolverProc()
  70       : HostResolverProc(NULL),
  71         num_requests_waiting_(0),
  72         num_slots_available_(0),
  73         requests_waiting_(&lock_),
  74         slots_available_(&lock_) {
  75   }
  76
  77   // Waits until |count| calls to |Resolve| are blocked. Returns false when
  78   // timed out.
  79   bool WaitFor(unsigned count) {
  80     base::AutoLock lock(lock_);
  81     base::Time start_time = base::Time::Now();
  82     while (num_requests_waiting_ < count) {
  83       requests_waiting_.TimedWait(TestTimeouts::action_timeout());
  84       if (base::Time::Now() > start_time + TestTimeouts::action_timeout())
  85         return false;
  86     }
  87     return true;
  88   }
  89
  90   // Signals |count| waiting calls to |Resolve|. First come first served.
  91   void SignalMultiple(unsigned count) {
  92     base::AutoLock lock(lock_);
  93     num_slots_available_ += count;
  94     slots_available_.Broadcast();
  95   }
  96
  97   // Signals all waiting calls to |Resolve|. Beware of races.
  98   void SignalAll() {
  99     base::AutoLock lock(lock_);
 100     num_slots_available_ = num_requests_waiting_;
 101     slots_available_.Broadcast();
 102   }
 103
 104   void AddRule(const std::string& hostname, AddressFamily family,
 105                const AddressList& result) {
 106     base::AutoLock lock(lock_);
 107     rules_[ResolveKey(hostname, family)] = result;
 108   }
 109
 110   void AddRule(const std::string& hostname, AddressFamily family,
 111                const std::string& ip_list) {
 112     AddressList result;
 113     int rv = ParseAddressList(ip_list, std::string(), &result);
 114     DCHECK_EQ(OK, rv);
 115     AddRule(hostname, family, result);
 116   }
 117
 118   void AddRuleForAllFamilies(const std::string& hostname,
 119                              const std::string& ip_list) {
 120     AddressList result;
 121     int rv = ParseAddressList(ip_list, std::string(), &result);
 122     DCHECK_EQ(OK, rv);
 123     AddRule(hostname, ADDRESS_FAMILY_UNSPECIFIED, result);
 124     AddRule(hostname, ADDRESS_FAMILY_IPV4, result);
 125     AddRule(hostname, ADDRESS_FAMILY_IPV6, result);
 126   }
 127
 128   virtual int Resolve(const std::string& hostname,
 129                       AddressFamily address_family,
 130                       HostResolverFlags host_resolver_flags,
 131                       AddressList* addrlist,
 132                       int* os_error) OVERRIDE {
 133     base::AutoLock lock(lock_);
 134     capture_list_.push_back(ResolveKey(hostname, address_family));
 135     ++num_requests_waiting_;
 136     requests_waiting_.Broadcast();
 137     while (!num_slots_available_)
 138       slots_available_.Wait();
 139     DCHECK_GT(num_requests_waiting_, 0u);
 140     --num_slots_available_;
 141     --num_requests_waiting_;
 142     if (rules_.empty()) {
 143       int rv = ParseAddressList("127.0.0.1", std::string(), addrlist);
 144       DCHECK_EQ(OK, rv);
 145       return OK;
 146     }
 147     ResolveKey key(hostname, address_family);
 148     if (rules_.count(key) == 0)
 149       return ERR_NAME_NOT_RESOLVED;
 150     *addrlist = rules_[key];
 151     return OK;
 152   }
 153
 154   CaptureList GetCaptureList() const {
 155     CaptureList copy;
 156     {
 157       base::AutoLock lock(lock_);
 158       copy = capture_list_;
 159     }
 160     return copy;
 161   }
 162
 163   bool HasBlockedRequests() const {
 164     base::AutoLock lock(lock_);
 165     return num_requests_waiting_ > num_slots_available_;
 166   }
 167
 168  protected:
 169   virtual ~MockHostResolverProc() {}
 170
 171  private:
 172   mutable base::Lock lock_;
 173   std::map<ResolveKey, AddressList> rules_;
 174   CaptureList capture_list_;
 175   unsigned num_requests_waiting_;
 176   unsigned num_slots_available_;
 177   base::ConditionVariable requests_waiting_;
 178   base::ConditionVariable slots_available_;
 179
 180   DISALLOW_COPY_AND_ASSIGN(MockHostResolverProc);
 181 };
 182
 183 bool AddressListContains(const AddressList& list, const std::string& address,
 184                          int port) {
 185   IPAddressNumber ip;
 186   bool rv = ParseIPLiteralToNumber(address, &ip);
 187   DCHECK(rv);
 188   return std::find(list.begin(),
 189                    list.end(),
 190                    IPEndPoint(ip, port)) != list.end();
 191 }
 192
 193 // A wrapper for requests to a HostResolver.
 194 class Request {
 195  public:
 196   // Base class of handlers to be executed on completion of requests.
 197   struct Handler {
 198     virtual ~Handler() {}
 199     virtual void Handle(Request* request) = 0;
 200   };
 201
 202   Request(const HostResolver::RequestInfo& info,
 203           RequestPriority priority,
 204           size_t index,
 205           HostResolver* resolver,
 206           Handler* handler)
 207       : info_(info),
 208         priority_(priority),
 209         index_(index),
 210         resolver_(resolver),
 211         handler_(handler),
 212         quit_on_complete_(false),
 213         result_(ERR_UNEXPECTED),
 214         handle_(NULL) {}
 215
 216   int Resolve() {
 217     DCHECK(resolver_);
 218     DCHECK(!handle_);
 219     list_ = AddressList();
 220     result_ = resolver_->Resolve(
 221         info_,
 222         priority_,
 223         &list_,
 224         base::Bind(&Request::OnComplete, base::Unretained(this)),
 225         &handle_,
 226         BoundNetLog());
 227     if (!list_.empty())
 228       EXPECT_EQ(OK, result_);
 229     return result_;
 230   }
 231
 232   int ResolveFromCache() {
 233     DCHECK(resolver_);
 234     DCHECK(!handle_);
 235     return resolver_->ResolveFromCache(info_, &list_, BoundNetLog());
 236   }
 237
 238   void Cancel() {
 239     DCHECK(resolver_);
 240     DCHECK(handle_);
 241     resolver_->CancelRequest(handle_);
 242     handle_ = NULL;
 243   }
 244
 245   const HostResolver::RequestInfo& info() const { return info_; }
 246   size_t index() const { return index_; }
 247   const AddressList& list() const { return list_; }
 248   int result() const { return result_; }
 249   bool completed() const { return result_ != ERR_IO_PENDING; }
 250   bool pending() const { return handle_ != NULL; }
 251
 252   bool HasAddress(const std::string& address, int port) const {
 253     return AddressListContains(list_, address, port);
 254   }
 255
 256   // Returns the number of addresses in |list_|.
 257   unsigned NumberOfAddresses() const {
 258     return list_.size();
 259   }
 260
 261   bool HasOneAddress(const std::string& address, int port) const {
 262     return HasAddress(address, port) && (NumberOfAddresses() == 1u);
 263   }
 264
 265   // Returns ERR_UNEXPECTED if timed out.
 266   int WaitForResult() {
 267     if (completed())
 268       return result_;
 269     base::CancelableClosure closure(base::MessageLoop::QuitClosure());
 270     base::MessageLoop::current()->PostDelayedTask(
 271         FROM_HERE, closure.callback(), TestTimeouts::action_max_timeout());
 272     quit_on_complete_ = true;
 273     base::MessageLoop::current()->Run();
 274     bool did_quit = !quit_on_complete_;
 275     quit_on_complete_ = false;
 276     closure.Cancel();
 277     if (did_quit)
 278       return result_;
 279     else
 280       return ERR_UNEXPECTED;
 281   }
 282
 283  private:
 284   void OnComplete(int rv) {
 285     EXPECT_TRUE(pending());
 286     EXPECT_EQ(ERR_IO_PENDING, result_);
 287     EXPECT_NE(ERR_IO_PENDING, rv);
 288     result_ = rv;
 289     handle_ = NULL;
 290     if (!list_.empty()) {
 291       EXPECT_EQ(OK, result_);
 292       EXPECT_EQ(info_.port(), list_.front().port());
 293     }
 294     if (handler_)
 295       handler_->Handle(this);
 296     if (quit_on_complete_) {
 297       base::MessageLoop::current()->Quit();
 298       quit_on_complete_ = false;
 299     }
 300   }
 301
 302   HostResolver::RequestInfo info_;
 303   RequestPriority priority_;
 304   size_t index_;
 305   HostResolver* resolver_;
 306   Handler* handler_;
 307   bool quit_on_complete_;
 308
 309   AddressList list_;
 310   int result_;
 311   HostResolver::RequestHandle handle_;
 312
 313   DISALLOW_COPY_AND_ASSIGN(Request);
 314 };
 315
 316 // Using LookupAttemptHostResolverProc simulate very long lookups, and control
 317 // which attempt resolves the host.
 318 class LookupAttemptHostResolverProc : public HostResolverProc {
 319  public:
 320   LookupAttemptHostResolverProc(HostResolverProc* previous,
 321                                 int attempt_number_to_resolve,
 322                                 int total_attempts)
 323       : HostResolverProc(previous),
 324         attempt_number_to_resolve_(attempt_number_to_resolve),
 325         current_attempt_number_(0),
 326         total_attempts_(total_attempts),
 327         total_attempts_resolved_(0),
 328         resolved_attempt_number_(0),
 329         all_done_(&lock_) {
 330   }
 331
 332   // Test harness will wait for all attempts to finish before checking the
 333   // results.
 334   void WaitForAllAttemptsToFinish(const base::TimeDelta& wait_time) {
 335     base::TimeTicks end_time = base::TimeTicks::Now() + wait_time;
 336     {
 337       base::AutoLock auto_lock(lock_);
 338       while (total_attempts_resolved_ != total_attempts_ &&
 339           base::TimeTicks::Now() < end_time) {
 340         all_done_.TimedWait(end_time - base::TimeTicks::Now());
 341       }
 342     }
 343   }
 344
 345   // All attempts will wait for an attempt to resolve the host.
 346   void WaitForAnAttemptToComplete() {
 347     base::TimeDelta wait_time = base::TimeDelta::FromSeconds(60);
 348     base::TimeTicks end_time = base::TimeTicks::Now() + wait_time;
 349     {
 350       base::AutoLock auto_lock(lock_);
 351       while (resolved_attempt_number_ == 0 && base::TimeTicks::Now() < end_time)
 352         all_done_.TimedWait(end_time - base::TimeTicks::Now());
 353     }
 354     all_done_.Broadcast();  // Tell all waiting attempts to proceed.
 355   }
 356
 357   // Returns the number of attempts that have finished the Resolve() method.
 358   int total_attempts_resolved() { return total_attempts_resolved_; }
 359
 360   // Returns the first attempt that that has resolved the host.
 361   int resolved_attempt_number() { return resolved_attempt_number_; }
 362
 363   // HostResolverProc methods.
 364   virtual int Resolve(const std::string& host,
 365                       AddressFamily address_family,
 366                       HostResolverFlags host_resolver_flags,
 367                       AddressList* addrlist,
 368                       int* os_error) OVERRIDE {
 369     bool wait_for_right_attempt_to_complete = true;
 370     {
 371       base::AutoLock auto_lock(lock_);
 372       ++current_attempt_number_;
 373       if (current_attempt_number_ == attempt_number_to_resolve_) {
 374         resolved_attempt_number_ = current_attempt_number_;
 375         wait_for_right_attempt_to_complete = false;
 376       }
 377     }
 378
 379     if (wait_for_right_attempt_to_complete)
 380       // Wait for the attempt_number_to_resolve_ attempt to resolve.
 381       WaitForAnAttemptToComplete();
 382
 383     int result = ResolveUsingPrevious(host, address_family, host_resolver_flags,
 384                                       addrlist, os_error);
 385
 386     {
 387       base::AutoLock auto_lock(lock_);
 388       ++total_attempts_resolved_;
 389     }
 390
 391     all_done_.Broadcast();  // Tell all attempts to proceed.
 392
 393     // Since any negative number is considered a network error, with -1 having
 394     // special meaning (ERR_IO_PENDING). We could return the attempt that has
 395     // resolved the host as a negative number. For example, if attempt number 3
 396     // resolves the host, then this method returns -4.
 397     if (result == OK)
 398       return -1 - resolved_attempt_number_;
 399     else
 400       return result;
 401   }
 402
 403  protected:
 404   virtual ~LookupAttemptHostResolverProc() {}
 405
 406  private:
 407   int attempt_number_to_resolve_;
 408   int current_attempt_number_;  // Incremented whenever Resolve is called.
 409   int total_attempts_;
 410   int total_attempts_resolved_;
 411   int resolved_attempt_number_;
 412
 413   // All attempts wait for right attempt to be resolve.
 414   base::Lock lock_;
 415   base::ConditionVariable all_done_;
 416 };
 417
 418 }  // namespace
 419
 420 class HostResolverImplTest : public testing::Test {
 421  public:
 422   static const int kDefaultPort = 80;
 423
 424   HostResolverImplTest() : proc_(new MockHostResolverProc()) {}
 425
 426   void CreateResolver() {
 427     CreateResolverWithLimitsAndParams(kMaxJobs,
 428                                       DefaultParams(proc_.get()));
 429   }
 430
 431   // This HostResolverImpl will only allow 1 outstanding resolve at a time and
 432   // perform no retries.
 433   void CreateSerialResolver() {
 434     HostResolverImpl::ProcTaskParams params = DefaultParams(proc_.get());
 435     params.max_retry_attempts = 0u;
 436     CreateResolverWithLimitsAndParams(1u, params);
 437   }
 438
 439  protected:
 440   // A Request::Handler which is a proxy to the HostResolverImplTest fixture.
 441   struct Handler : public Request::Handler {
 442     virtual ~Handler() {}
 443
 444     // Proxy functions so that classes derived from Handler can access them.
 445     Request* CreateRequest(const HostResolver::RequestInfo& info,
 446                            RequestPriority priority) {
 447       return test->CreateRequest(info, priority);
 448     }
 449     Request* CreateRequest(const std::string& hostname, int port) {
 450       return test->CreateRequest(hostname, port);
 451     }
 452     Request* CreateRequest(const std::string& hostname) {
 453       return test->CreateRequest(hostname);
 454     }
 455     ScopedVector<Request>& requests() { return test->requests_; }
 456
 457     void DeleteResolver() { test->resolver_.reset(); }
 458
 459     HostResolverImplTest* test;
 460   };
 461
 462   // testing::Test implementation:
 463   virtual void SetUp() OVERRIDE {
 464     CreateResolver();
 465   }
 466
 467   virtual void TearDown() OVERRIDE {
 468     if (resolver_.get())
 469       EXPECT_EQ(0u, resolver_->num_running_dispatcher_jobs_for_tests());
 470     EXPECT_FALSE(proc_->HasBlockedRequests());
 471   }
 472
 473   virtual void CreateResolverWithLimitsAndParams(
 474       size_t max_concurrent_resolves,
 475       const HostResolverImpl::ProcTaskParams& params) {
 476     HostResolverImpl::Options options = DefaultOptions();
 477     options.max_concurrent_resolves = max_concurrent_resolves;
 478     resolver_.reset(new HostResolverImpl(options, NULL));
 479     resolver_->set_proc_params_for_test(params);
 480   }
 481
 482   // The Request will not be made until a call to |Resolve()|, and the Job will
 483   // not start until released by |proc_->SignalXXX|.
 484   Request* CreateRequest(const HostResolver::RequestInfo& info,
 485                          RequestPriority priority) {
 486     Request* req = new Request(
 487         info, priority, requests_.size(), resolver_.get(), handler_.get());
 488     requests_.push_back(req);
 489     return req;
 490   }
 491
 492   Request* CreateRequest(const std::string& hostname,
 493                          int port,
 494                          RequestPriority priority,
 495                          AddressFamily family) {
 496     HostResolver::RequestInfo info(HostPortPair(hostname, port));
 497     info.set_address_family(family);
 498     return CreateRequest(info, priority);
 499   }
 500
 501   Request* CreateRequest(const std::string& hostname,
 502                          int port,
 503                          RequestPriority priority) {
 504     return CreateRequest(hostname, port, priority, ADDRESS_FAMILY_UNSPECIFIED);
 505   }
 506
 507   Request* CreateRequest(const std::string& hostname, int port) {
 508     return CreateRequest(hostname, port, MEDIUM);
 509   }
 510
 511   Request* CreateRequest(const std::string& hostname) {
 512     return CreateRequest(hostname, kDefaultPort);
 513   }
 514
 515   void set_handler(Handler* handler) {
 516     handler_.reset(handler);
 517     handler_->test = this;
 518   }
 519
 520   // Friendship is not inherited, so use proxies to access those.
 521   size_t num_running_dispatcher_jobs() const {
 522     DCHECK(resolver_.get());
 523     return resolver_->num_running_dispatcher_jobs_for_tests();
 524   }
 525
 526   void set_fallback_to_proctask(bool fallback_to_proctask) {
 527     DCHECK(resolver_.get());
 528     resolver_->fallback_to_proctask_ = fallback_to_proctask;
 529   }
 530
 531   static unsigned maximum_dns_failures() {
 532     return HostResolverImpl::kMaximumDnsFailures;
 533   }
 534
 535   scoped_refptr<MockHostResolverProc> proc_;
 536   scoped_ptr<HostResolverImpl> resolver_;
 537   ScopedVector<Request> requests_;
 538
 539   scoped_ptr<Handler> handler_;
 540 };
 541
 542 TEST_F(HostResolverImplTest, AsynchronousLookup) {
 543   proc_->AddRuleForAllFamilies("just.testing", "192.168.1.42");
 544   proc_->SignalMultiple(1u);
 545
 546   Request* req = CreateRequest("just.testing", 80);
 547   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 548   EXPECT_EQ(OK, req->WaitForResult());
 549
 550   EXPECT_TRUE(req->HasOneAddress("192.168.1.42", 80));
 551
 552   EXPECT_EQ("just.testing", proc_->GetCaptureList()[0].hostname);
 553 }
 554
 555 TEST_F(HostResolverImplTest, EmptyListMeansNameNotResolved) {
 556   proc_->AddRuleForAllFamilies("just.testing", "");
 557   proc_->SignalMultiple(1u);
 558
 559   Request* req = CreateRequest("just.testing", 80);
 560   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 561   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->WaitForResult());
 562   EXPECT_EQ(0u, req->NumberOfAddresses());
 563   EXPECT_EQ("just.testing", proc_->GetCaptureList()[0].hostname);
 564 }
 565
 566 TEST_F(HostResolverImplTest, FailedAsynchronousLookup) {
 567   proc_->AddRuleForAllFamilies(std::string(),
 568                                "0.0.0.0");  // Default to failures.
 569   proc_->SignalMultiple(1u);
 570
 571   Request* req = CreateRequest("just.testing", 80);
 572   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 573   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->WaitForResult());
 574
 575   EXPECT_EQ("just.testing", proc_->GetCaptureList()[0].hostname);
 576
 577   // Also test that the error is not cached.
 578   EXPECT_EQ(ERR_DNS_CACHE_MISS, req->ResolveFromCache());
 579 }
 580
 581 TEST_F(HostResolverImplTest, AbortedAsynchronousLookup) {
 582   Request* req0 = CreateRequest("just.testing", 80);
 583   EXPECT_EQ(ERR_IO_PENDING, req0->Resolve());
 584
 585   EXPECT_TRUE(proc_->WaitFor(1u));
 586
 587   // Resolver is destroyed while job is running on WorkerPool.
 588   resolver_.reset();
 589
 590   proc_->SignalAll();
 591
 592   // To ensure there was no spurious callback, complete with a new resolver.
 593   CreateResolver();
 594   Request* req1 = CreateRequest("just.testing", 80);
 595   EXPECT_EQ(ERR_IO_PENDING, req1->Resolve());
 596
 597   proc_->SignalMultiple(2u);
 598
 599   EXPECT_EQ(OK, req1->WaitForResult());
 600
 601   // This request was canceled.
 602   EXPECT_FALSE(req0->completed());
 603 }
 604
 605 #if defined(THREAD_SANITIZER)
 606 // Use of WorkerPool in HostResolverImpl causes a data race. crbug.com/334140
 607 #define MAYBE_NumericIPv4Address DISABLED_NumericIPv4Address
 608 #else
 609 #define MAYBE_NumericIPv4Address NumericIPv4Address
 610 #endif
 611 TEST_F(HostResolverImplTest, MAYBE_NumericIPv4Address) {
 612   // Stevens says dotted quads with AI_UNSPEC resolve to a single sockaddr_in.
 613   Request* req = CreateRequest("127.1.2.3", 5555);
 614   EXPECT_EQ(OK, req->Resolve());
 615
 616   EXPECT_TRUE(req->HasOneAddress("127.1.2.3", 5555));
 617 }
 618
 619 #if defined(THREAD_SANITIZER)
 620 // Use of WorkerPool in HostResolverImpl causes a data race. crbug.com/334140
 621 #define MAYBE_NumericIPv6Address DISABLED_NumericIPv6Address
 622 #else
 623 #define MAYBE_NumericIPv6Address NumericIPv6Address
 624 #endif
 625 TEST_F(HostResolverImplTest, MAYBE_NumericIPv6Address) {
 626   // Resolve a plain IPv6 address.  Don't worry about [brackets], because
 627   // the caller should have removed them.
 628   Request* req = CreateRequest("2001:db8::1", 5555);
 629   EXPECT_EQ(OK, req->Resolve());
 630
 631   EXPECT_TRUE(req->HasOneAddress("2001:db8::1", 5555));
 632 }
 633
 634 #if defined(THREAD_SANITIZER)
 635 // Use of WorkerPool in HostResolverImpl causes a data race. crbug.com/334140
 636 #define MAYBE_EmptyHost DISABLED_EmptyHost
 637 #else
 638 #define MAYBE_EmptyHost EmptyHost
 639 #endif
 640 TEST_F(HostResolverImplTest, MAYBE_EmptyHost) {
 641   Request* req = CreateRequest(std::string(), 5555);
 642   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->Resolve());
 643 }
 644
 645 #if defined(THREAD_SANITIZER)
 646 // There's a data race in this test that may lead to use-after-free.
 647 // If the test starts to crash without ThreadSanitizer it needs to be disabled
 648 // globally. See http://crbug.com/268946 (stacks for this test in
 649 // crbug.com/333567).
 650 #define MAYBE_EmptyDotsHost DISABLED_EmptyDotsHost
 651 #else
 652 #define MAYBE_EmptyDotsHost EmptyDotsHost
 653 #endif
 654 TEST_F(HostResolverImplTest, MAYBE_EmptyDotsHost) {
 655   for (int i = 0; i < 16; ++i) {
 656     Request* req = CreateRequest(std::string(i, '.'), 5555);
 657     EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->Resolve());
 658   }
 659 }
 660
 661 #if defined(THREAD_SANITIZER)
 662 // There's a data race in this test that may lead to use-after-free.
 663 // If the test starts to crash without ThreadSanitizer it needs to be disabled
 664 // globally. See http://crbug.com/268946.
 665 #define MAYBE_LongHost DISABLED_LongHost
 666 #else
 667 #define MAYBE_LongHost LongHost
 668 #endif
 669 TEST_F(HostResolverImplTest, MAYBE_LongHost) {
 670   Request* req = CreateRequest(std::string(4097, 'a'), 5555);
 671   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->Resolve());
 672 }
 673
 674 TEST_F(HostResolverImplTest, DeDupeRequests) {
 675   // Start 5 requests, duplicating hosts "a" and "b". Since the resolver_proc is
 676   // blocked, these should all pile up until we signal it.
 677   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80)->Resolve());
 678   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 80)->Resolve());
 679   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 81)->Resolve());
 680   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 82)->Resolve());
 681   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 83)->Resolve());
 682
 683   proc_->SignalMultiple(2u);  // One for "a", one for "b".
 684
 685   for (size_t i = 0; i < requests_.size(); ++i) {
 686     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
 687   }
 688 }
 689
 690 TEST_F(HostResolverImplTest, CancelMultipleRequests) {
 691   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80)->Resolve());
 692   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 80)->Resolve());
 693   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 81)->Resolve());
 694   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 82)->Resolve());
 695   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 83)->Resolve());
 696
 697   // Cancel everything except request for ("a", 82).
 698   requests_[0]->Cancel();
 699   requests_[1]->Cancel();
 700   requests_[2]->Cancel();
 701   requests_[4]->Cancel();
 702
 703   proc_->SignalMultiple(2u);  // One for "a", one for "b".
 704
 705   EXPECT_EQ(OK, requests_[3]->WaitForResult());
 706 }
 707
 708 TEST_F(HostResolverImplTest, CanceledRequestsReleaseJobSlots) {
 709   // Fill up the dispatcher and queue.
 710   for (unsigned i = 0; i < kMaxJobs + 1; ++i) {
 711     std::string hostname = "a_";
 712     hostname[1] = 'a' + i;
 713     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname, 80)->Resolve());
 714     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname, 81)->Resolve());
 715   }
 716
 717   EXPECT_TRUE(proc_->WaitFor(kMaxJobs));
 718
 719   // Cancel all but last two.
 720   for (unsigned i = 0; i < requests_.size() - 2; ++i) {
 721     requests_[i]->Cancel();
 722   }
 723
 724   EXPECT_TRUE(proc_->WaitFor(kMaxJobs + 1));
 725
 726   proc_->SignalAll();
 727
 728   size_t num_requests = requests_.size();
 729   EXPECT_EQ(OK, requests_[num_requests - 1]->WaitForResult());
 730   EXPECT_EQ(OK, requests_[num_requests - 2]->result());
 731 }
 732
 733 TEST_F(HostResolverImplTest, CancelWithinCallback) {
 734   struct MyHandler : public Handler {
 735     virtual void Handle(Request* req) OVERRIDE {
 736       // Port 80 is the first request that the callback will be invoked for.
 737       // While we are executing within that callback, cancel the other requests
 738       // in the job and start another request.
 739       if (req->index() == 0) {
 740         // Once "a:80" completes, it will cancel "a:81" and "a:82".
 741         requests()[1]->Cancel();
 742         requests()[2]->Cancel();
 743       }
 744     }
 745   };
 746   set_handler(new MyHandler());
 747
 748   for (size_t i = 0; i < 4; ++i) {
 749     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80 + i)->Resolve()) << i;
 750   }
 751
 752   proc_->SignalMultiple(2u);  // One for "a". One for "finalrequest".
 753
 754   EXPECT_EQ(OK, requests_[0]->WaitForResult());
 755
 756   Request* final_request = CreateRequest("finalrequest", 70);
 757   EXPECT_EQ(ERR_IO_PENDING, final_request->Resolve());
 758   EXPECT_EQ(OK, final_request->WaitForResult());
 759   EXPECT_TRUE(requests_[3]->completed());
 760 }
 761
 762 TEST_F(HostResolverImplTest, DeleteWithinCallback) {
 763   struct MyHandler : public Handler {
 764     virtual void Handle(Request* req) OVERRIDE {
 765       EXPECT_EQ("a", req->info().hostname());
 766       EXPECT_EQ(80, req->info().port());
 767
 768       DeleteResolver();
 769
 770       // Quit after returning from OnCompleted (to give it a chance at
 771       // incorrectly running the cancelled tasks).
 772       base::MessageLoop::current()->PostTask(FROM_HERE,
 773                                              base::MessageLoop::QuitClosure());
 774     }
 775   };
 776   set_handler(new MyHandler());
 777
 778   for (size_t i = 0; i < 4; ++i) {
 779     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80 + i)->Resolve()) << i;
 780   }
 781
 782   proc_->SignalMultiple(1u);  // One for "a".
 783
 784   // |MyHandler| will send quit message once all the requests have finished.
 785   base::MessageLoop::current()->Run();
 786 }
 787
 788 TEST_F(HostResolverImplTest, DeleteWithinAbortedCallback) {
 789   struct MyHandler : public Handler {
 790     virtual void Handle(Request* req) OVERRIDE {
 791       EXPECT_EQ("a", req->info().hostname());
 792       EXPECT_EQ(80, req->info().port());
 793
 794       DeleteResolver();
 795
 796       // Quit after returning from OnCompleted (to give it a chance at
 797       // incorrectly running the cancelled tasks).
 798       base::MessageLoop::current()->PostTask(FROM_HERE,
 799                                              base::MessageLoop::QuitClosure());
 800     }
 801   };
 802   set_handler(new MyHandler());
 803
 804   // This test assumes that the Jobs will be Aborted in order ["a", "b"]
 805   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80)->Resolve());
 806   // HostResolverImpl will be deleted before later Requests can complete.
 807   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 81)->Resolve());
 808   // Job for 'b' will be aborted before it can complete.
 809   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 82)->Resolve());
 810   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b", 83)->Resolve());
 811
 812   EXPECT_TRUE(proc_->WaitFor(1u));
 813
 814   // Triggering an IP address change.
 815   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
 816
 817   // |MyHandler| will send quit message once all the requests have finished.
 818   base::MessageLoop::current()->Run();
 819
 820   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[0]->result());
 821   EXPECT_EQ(ERR_IO_PENDING, requests_[1]->result());
 822   EXPECT_EQ(ERR_IO_PENDING, requests_[2]->result());
 823   EXPECT_EQ(ERR_IO_PENDING, requests_[3]->result());
 824   // Clean up.
 825   proc_->SignalMultiple(requests_.size());
 826 }
 827
 828 TEST_F(HostResolverImplTest, StartWithinCallback) {
 829   struct MyHandler : public Handler {
 830     virtual void Handle(Request* req) OVERRIDE {
 831       if (req->index() == 0) {
 832         // On completing the first request, start another request for "a".
 833         // Since caching is disabled, this will result in another async request.
 834         EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 70)->Resolve());
 835       }
 836     }
 837   };
 838   set_handler(new MyHandler());
 839
 840   // Turn off caching for this host resolver.
 841   HostResolver::Options options = DefaultOptions();
 842   options.enable_caching = false;
 843   resolver_.reset(new HostResolverImpl(options, NULL));
 844   resolver_->set_proc_params_for_test(DefaultParams(proc_.get()));
 845
 846   for (size_t i = 0; i < 4; ++i) {
 847     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80 + i)->Resolve()) << i;
 848   }
 849
 850   proc_->SignalMultiple(2u);  // One for "a". One for the second "a".
 851
 852   EXPECT_EQ(OK, requests_[0]->WaitForResult());
 853   ASSERT_EQ(5u, requests_.size());
 854   EXPECT_EQ(OK, requests_.back()->WaitForResult());
 855
 856   EXPECT_EQ(2u, proc_->GetCaptureList().size());
 857 }
 858
 859 TEST_F(HostResolverImplTest, BypassCache) {
 860   struct MyHandler : public Handler {
 861     virtual void Handle(Request* req) OVERRIDE {
 862       if (req->index() == 0) {
 863         // On completing the first request, start another request for "a".
 864         // Since caching is enabled, this should complete synchronously.
 865         std::string hostname = req->info().hostname();
 866         EXPECT_EQ(OK, CreateRequest(hostname, 70)->Resolve());
 867         EXPECT_EQ(OK, CreateRequest(hostname, 75)->ResolveFromCache());
 868
 869         // Ok good. Now make sure that if we ask to bypass the cache, it can no
 870         // longer service the request synchronously.
 871         HostResolver::RequestInfo info(HostPortPair(hostname, 71));
 872         info.set_allow_cached_response(false);
 873         EXPECT_EQ(ERR_IO_PENDING,
 874                   CreateRequest(info, DEFAULT_PRIORITY)->Resolve());
 875       } else if (71 == req->info().port()) {
 876         // Test is done.
 877         base::MessageLoop::current()->Quit();
 878       } else {
 879         FAIL() << "Unexpected request";
 880       }
 881     }
 882   };
 883   set_handler(new MyHandler());
 884
 885   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a", 80)->Resolve());
 886   proc_->SignalMultiple(3u);  // Only need two, but be generous.
 887
 888   // |verifier| will send quit message once all the requests have finished.
 889   base::MessageLoop::current()->Run();
 890   EXPECT_EQ(2u, proc_->GetCaptureList().size());
 891 }
 892
 893 // Test that IP address changes flush the cache.
 894 TEST_F(HostResolverImplTest, FlushCacheOnIPAddressChange) {
 895   proc_->SignalMultiple(2u);  // One before the flush, one after.
 896
 897   Request* req = CreateRequest("host1", 70);
 898   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 899   EXPECT_EQ(OK, req->WaitForResult());
 900
 901   req = CreateRequest("host1", 75);
 902   EXPECT_EQ(OK, req->Resolve());  // Should complete synchronously.
 903
 904   // Flush cache by triggering an IP address change.
 905   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
 906   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
 907
 908   // Resolve "host1" again -- this time it won't be served from cache, so it
 909   // will complete asynchronously.
 910   req = CreateRequest("host1", 80);
 911   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 912   EXPECT_EQ(OK, req->WaitForResult());
 913 }
 914
 915 // Test that IP address changes send ERR_NETWORK_CHANGED to pending requests.
 916 TEST_F(HostResolverImplTest, AbortOnIPAddressChanged) {
 917   Request* req = CreateRequest("host1", 70);
 918   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
 919
 920   EXPECT_TRUE(proc_->WaitFor(1u));
 921   // Triggering an IP address change.
 922   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
 923   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
 924   proc_->SignalAll();
 925
 926   EXPECT_EQ(ERR_NETWORK_CHANGED, req->WaitForResult());
 927   EXPECT_EQ(0u, resolver_->GetHostCache()->size());
 928 }
 929
 930 // Obey pool constraints after IP address has changed.
 931 TEST_F(HostResolverImplTest, ObeyPoolConstraintsAfterIPAddressChange) {
 932   // Runs at most one job at a time.
 933   CreateSerialResolver();
 934   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("a")->Resolve());
 935   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("b")->Resolve());
 936   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("c")->Resolve());
 937
 938   EXPECT_TRUE(proc_->WaitFor(1u));
 939   // Triggering an IP address change.
 940   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
 941   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
 942   proc_->SignalMultiple(3u);  // Let the false-start go so that we can catch it.
 943
 944   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[0]->WaitForResult());
 945
 946   EXPECT_EQ(1u, num_running_dispatcher_jobs());
 947
 948   EXPECT_FALSE(requests_[1]->completed());
 949   EXPECT_FALSE(requests_[2]->completed());
 950
 951   EXPECT_EQ(OK, requests_[2]->WaitForResult());
 952   EXPECT_EQ(OK, requests_[1]->result());
 953 }
 954
 955 // Tests that a new Request made from the callback of a previously aborted one
 956 // will not be aborted.
 957 TEST_F(HostResolverImplTest, AbortOnlyExistingRequestsOnIPAddressChange) {
 958   struct MyHandler : public Handler {
 959     virtual void Handle(Request* req) OVERRIDE {
 960       // Start new request for a different hostname to ensure that the order
 961       // of jobs in HostResolverImpl is not stable.
 962       std::string hostname;
 963       if (req->index() == 0)
 964         hostname = "zzz";
 965       else if (req->index() == 1)
 966         hostname = "aaa";
 967       else if (req->index() == 2)
 968         hostname = "eee";
 969       else
 970         return;  // A request started from within MyHandler.
 971       EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname)->Resolve()) << hostname;
 972     }
 973   };
 974   set_handler(new MyHandler());
 975
 976   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("bbb")->Resolve());
 977   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("eee")->Resolve());
 978   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ccc")->Resolve());
 979
 980   // Wait until all are blocked;
 981   EXPECT_TRUE(proc_->WaitFor(3u));
 982   // Trigger an IP address change.
 983   NetworkChangeNotifier::NotifyObserversOfIPAddressChangeForTests();
 984   // This should abort all running jobs.
 985   base::MessageLoop::current()->RunUntilIdle();
 986   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[0]->result());
 987   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[1]->result());
 988   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[2]->result());
 989   ASSERT_EQ(6u, requests_.size());
 990   // Unblock all calls to proc.
 991   proc_->SignalMultiple(requests_.size());
 992   // Run until the re-started requests finish.
 993   EXPECT_EQ(OK, requests_[3]->WaitForResult());
 994   EXPECT_EQ(OK, requests_[4]->WaitForResult());
 995   EXPECT_EQ(OK, requests_[5]->WaitForResult());
 996   // Verify that results of aborted Jobs were not cached.
 997   EXPECT_EQ(6u, proc_->GetCaptureList().size());
 998   EXPECT_EQ(3u, resolver_->GetHostCache()->size());
 999 }
1000
1001 // Tests that when the maximum threads is set to 1, requests are dequeued
1002 // in order of priority.
1003 TEST_F(HostResolverImplTest, HigherPriorityRequestsStartedFirst) {
1004   CreateSerialResolver();
1005
1006   // Note that at this point the MockHostResolverProc is blocked, so any
1007   // requests we make will not complete.
1008   CreateRequest("req0", 80, LOW);
1009   CreateRequest("req1", 80, MEDIUM);
1010   CreateRequest("req2", 80, MEDIUM);
1011   CreateRequest("req3", 80, LOW);
1012   CreateRequest("req4", 80, HIGHEST);
1013   CreateRequest("req5", 80, LOW);
1014   CreateRequest("req6", 80, LOW);
1015   CreateRequest("req5", 80, HIGHEST);
1016
1017   for (size_t i = 0; i < requests_.size(); ++i) {
1018     EXPECT_EQ(ERR_IO_PENDING, requests_[i]->Resolve()) << i;
1019   }
1020
1021   // Unblock the resolver thread so the requests can run.
1022   proc_->SignalMultiple(requests_.size());  // More than needed.
1023
1024   // Wait for all the requests to complete succesfully.
1025   for (size_t i = 0; i < requests_.size(); ++i) {
1026     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1027   }
1028
1029   // Since we have restricted to a single concurrent thread in the jobpool,
1030   // the requests should complete in order of priority (with the exception
1031   // of the first request, which gets started right away, since there is
1032   // nothing outstanding).
1033   MockHostResolverProc::CaptureList capture_list = proc_->GetCaptureList();
1034   ASSERT_EQ(7u, capture_list.size());
1035
1036   EXPECT_EQ("req0", capture_list[0].hostname);
1037   EXPECT_EQ("req4", capture_list[1].hostname);
1038   EXPECT_EQ("req5", capture_list[2].hostname);
1039   EXPECT_EQ("req1", capture_list[3].hostname);
1040   EXPECT_EQ("req2", capture_list[4].hostname);
1041   EXPECT_EQ("req3", capture_list[5].hostname);
1042   EXPECT_EQ("req6", capture_list[6].hostname);
1043 }
1044
1045 // Try cancelling a job which has not started yet.
1046 TEST_F(HostResolverImplTest, CancelPendingRequest) {
1047   CreateSerialResolver();
1048
1049   CreateRequest("req0", 80, LOWEST);
1050   CreateRequest("req1", 80, HIGHEST);  // Will cancel.
1051   CreateRequest("req2", 80, MEDIUM);
1052   CreateRequest("req3", 80, LOW);
1053   CreateRequest("req4", 80, HIGHEST);  // Will cancel.
1054   CreateRequest("req5", 80, LOWEST);   // Will cancel.
1055   CreateRequest("req6", 80, MEDIUM);
1056
1057   // Start all of the requests.
1058   for (size_t i = 0; i < requests_.size(); ++i) {
1059     EXPECT_EQ(ERR_IO_PENDING, requests_[i]->Resolve()) << i;
1060   }
1061
1062   // Cancel some requests
1063   requests_[1]->Cancel();
1064   requests_[4]->Cancel();
1065   requests_[5]->Cancel();
1066
1067   // Unblock the resolver thread so the requests can run.
1068   proc_->SignalMultiple(requests_.size());  // More than needed.
1069
1070   // Wait for all the requests to complete succesfully.
1071   for (size_t i = 0; i < requests_.size(); ++i) {
1072     if (!requests_[i]->pending())
1073       continue;  // Don't wait for the requests we cancelled.
1074     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1075   }
1076
1077   // Verify that they called out the the resolver proc (which runs on the
1078   // resolver thread) in the expected order.
1079   MockHostResolverProc::CaptureList capture_list = proc_->GetCaptureList();
1080   ASSERT_EQ(4u, capture_list.size());
1081
1082   EXPECT_EQ("req0", capture_list[0].hostname);
1083   EXPECT_EQ("req2", capture_list[1].hostname);
1084   EXPECT_EQ("req6", capture_list[2].hostname);
1085   EXPECT_EQ("req3", capture_list[3].hostname);
1086 }
1087
1088 // Test that when too many requests are enqueued, old ones start to be aborted.
1089 TEST_F(HostResolverImplTest, QueueOverflow) {
1090   CreateSerialResolver();
1091
1092   // Allow only 3 queued jobs.
1093   const size_t kMaxPendingJobs = 3u;
1094   resolver_->SetMaxQueuedJobs(kMaxPendingJobs);
1095
1096   // Note that at this point the MockHostResolverProc is blocked, so any
1097   // requests we make will not complete.
1098
1099   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req0", 80, LOWEST)->Resolve());
1100   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req1", 80, HIGHEST)->Resolve());
1101   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req2", 80, MEDIUM)->Resolve());
1102   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req3", 80, MEDIUM)->Resolve());
1103
1104   // At this point, there are 3 enqueued jobs.
1105   // Insertion of subsequent requests will cause evictions
1106   // based on priority.
1107
1108   EXPECT_EQ(ERR_HOST_RESOLVER_QUEUE_TOO_LARGE,
1109             CreateRequest("req4", 80, LOW)->Resolve());  // Evicts itself!
1110
1111   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req5", 80, MEDIUM)->Resolve());
1112   EXPECT_EQ(ERR_HOST_RESOLVER_QUEUE_TOO_LARGE, requests_[2]->result());
1113   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req6", 80, HIGHEST)->Resolve());
1114   EXPECT_EQ(ERR_HOST_RESOLVER_QUEUE_TOO_LARGE, requests_[3]->result());
1115   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("req7", 80, MEDIUM)->Resolve());
1116   EXPECT_EQ(ERR_HOST_RESOLVER_QUEUE_TOO_LARGE, requests_[5]->result());
1117
1118   // Unblock the resolver thread so the requests can run.
1119   proc_->SignalMultiple(4u);
1120
1121   // The rest should succeed.
1122   EXPECT_EQ(OK, requests_[7]->WaitForResult());
1123   EXPECT_EQ(OK, requests_[0]->result());
1124   EXPECT_EQ(OK, requests_[1]->result());
1125   EXPECT_EQ(OK, requests_[6]->result());
1126
1127   // Verify that they called out the the resolver proc (which runs on the
1128   // resolver thread) in the expected order.
1129   MockHostResolverProc::CaptureList capture_list = proc_->GetCaptureList();
1130   ASSERT_EQ(4u, capture_list.size());
1131
1132   EXPECT_EQ("req0", capture_list[0].hostname);
1133   EXPECT_EQ("req1", capture_list[1].hostname);
1134   EXPECT_EQ("req6", capture_list[2].hostname);
1135   EXPECT_EQ("req7", capture_list[3].hostname);
1136
1137   // Verify that the evicted (incomplete) requests were not cached.
1138   EXPECT_EQ(4u, resolver_->GetHostCache()->size());
1139
1140   for (size_t i = 0; i < requests_.size(); ++i) {
1141     EXPECT_TRUE(requests_[i]->completed()) << i;
1142   }
1143 }
1144
1145 // Tests that after changing the default AddressFamily to IPV4, requests
1146 // with UNSPECIFIED address family map to IPV4.
1147 TEST_F(HostResolverImplTest, SetDefaultAddressFamily_IPv4) {
1148   CreateSerialResolver();  // To guarantee order of resolutions.
1149
1150   proc_->AddRule("h1", ADDRESS_FAMILY_IPV4, "1.0.0.1");
1151   proc_->AddRule("h1", ADDRESS_FAMILY_IPV6, "::2");
1152
1153   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1154
1155   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_UNSPECIFIED);
1156   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_IPV4);
1157   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_IPV6);
1158
1159   // Start all of the requests.
1160   for (size_t i = 0; i < requests_.size(); ++i) {
1161     EXPECT_EQ(ERR_IO_PENDING, requests_[i]->Resolve()) << i;
1162   }
1163
1164   proc_->SignalMultiple(requests_.size());
1165
1166   // Wait for all the requests to complete.
1167   for (size_t i = 0u; i < requests_.size(); ++i) {
1168     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1169   }
1170
1171   // Since the requests all had the same priority and we limited the thread
1172   // count to 1, they should have completed in the same order as they were
1173   // requested. Moreover, request0 and request1 will have been serviced by
1174   // the same job.
1175
1176   MockHostResolverProc::CaptureList capture_list = proc_->GetCaptureList();
1177   ASSERT_EQ(2u, capture_list.size());
1178
1179   EXPECT_EQ("h1", capture_list[0].hostname);
1180   EXPECT_EQ(ADDRESS_FAMILY_IPV4, capture_list[0].address_family);
1181
1182   EXPECT_EQ("h1", capture_list[1].hostname);
1183   EXPECT_EQ(ADDRESS_FAMILY_IPV6, capture_list[1].address_family);
1184
1185   // Now check that the correct resolved IP addresses were returned.
1186   EXPECT_TRUE(requests_[0]->HasOneAddress("1.0.0.1", 80));
1187   EXPECT_TRUE(requests_[1]->HasOneAddress("1.0.0.1", 80));
1188   EXPECT_TRUE(requests_[2]->HasOneAddress("::2", 80));
1189 }
1190
1191 // This is the exact same test as SetDefaultAddressFamily_IPv4, except the
1192 // default family is set to IPv6 and the family of requests is flipped where
1193 // specified.
1194 TEST_F(HostResolverImplTest, SetDefaultAddressFamily_IPv6) {
1195   CreateSerialResolver();  // To guarantee order of resolutions.
1196
1197   // Don't use IPv6 replacements here since some systems don't support it.
1198   proc_->AddRule("h1", ADDRESS_FAMILY_IPV4, "1.0.0.1");
1199   proc_->AddRule("h1", ADDRESS_FAMILY_IPV6, "::2");
1200
1201   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV6);
1202
1203   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_UNSPECIFIED);
1204   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_IPV6);
1205   CreateRequest("h1", 80, MEDIUM, ADDRESS_FAMILY_IPV4);
1206
1207   // Start all of the requests.
1208   for (size_t i = 0; i < requests_.size(); ++i) {
1209     EXPECT_EQ(ERR_IO_PENDING, requests_[i]->Resolve()) << i;
1210   }
1211
1212   proc_->SignalMultiple(requests_.size());
1213
1214   // Wait for all the requests to complete.
1215   for (size_t i = 0u; i < requests_.size(); ++i) {
1216     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1217   }
1218
1219   // Since the requests all had the same priority and we limited the thread
1220   // count to 1, they should have completed in the same order as they were
1221   // requested. Moreover, request0 and request1 will have been serviced by
1222   // the same job.
1223
1224   MockHostResolverProc::CaptureList capture_list = proc_->GetCaptureList();
1225   ASSERT_EQ(2u, capture_list.size());
1226
1227   EXPECT_EQ("h1", capture_list[0].hostname);
1228   EXPECT_EQ(ADDRESS_FAMILY_IPV6, capture_list[0].address_family);
1229
1230   EXPECT_EQ("h1", capture_list[1].hostname);
1231   EXPECT_EQ(ADDRESS_FAMILY_IPV4, capture_list[1].address_family);
1232
1233   // Now check that the correct resolved IP addresses were returned.
1234   EXPECT_TRUE(requests_[0]->HasOneAddress("::2", 80));
1235   EXPECT_TRUE(requests_[1]->HasOneAddress("::2", 80));
1236   EXPECT_TRUE(requests_[2]->HasOneAddress("1.0.0.1", 80));
1237 }
1238
1239 TEST_F(HostResolverImplTest, ResolveFromCache) {
1240   proc_->AddRuleForAllFamilies("just.testing", "192.168.1.42");
1241   proc_->SignalMultiple(1u);  // Need only one.
1242
1243   HostResolver::RequestInfo info(HostPortPair("just.testing", 80));
1244
1245   // First hit will miss the cache.
1246   EXPECT_EQ(ERR_DNS_CACHE_MISS,
1247             CreateRequest(info, DEFAULT_PRIORITY)->ResolveFromCache());
1248
1249   // This time, we fetch normally.
1250   EXPECT_EQ(ERR_IO_PENDING, CreateRequest(info, DEFAULT_PRIORITY)->Resolve());
1251   EXPECT_EQ(OK, requests_[1]->WaitForResult());
1252
1253   // Now we should be able to fetch from the cache.
1254   EXPECT_EQ(OK, CreateRequest(info, DEFAULT_PRIORITY)->ResolveFromCache());
1255   EXPECT_TRUE(requests_[2]->HasOneAddress("192.168.1.42", 80));
1256 }
1257
1258 // Test the retry attempts simulating host resolver proc that takes too long.
1259 TEST_F(HostResolverImplTest, MultipleAttempts) {
1260   // Total number of attempts would be 3 and we want the 3rd attempt to resolve
1261   // the host. First and second attempt will be forced to sleep until they get
1262   // word that a resolution has completed. The 3rd resolution attempt will try
1263   // to get done ASAP, and won't sleep..
1264   int kAttemptNumberToResolve = 3;
1265   int kTotalAttempts = 3;
1266
1267   scoped_refptr<LookupAttemptHostResolverProc> resolver_proc(
1268       new LookupAttemptHostResolverProc(
1269           NULL, kAttemptNumberToResolve, kTotalAttempts));
1270
1271   HostResolverImpl::ProcTaskParams params = DefaultParams(resolver_proc.get());
1272
1273   // Specify smaller interval for unresponsive_delay_ for HostResolverImpl so
1274   // that unit test runs faster. For example, this test finishes in 1.5 secs
1275   // (500ms * 3).
1276   params.unresponsive_delay = base::TimeDelta::FromMilliseconds(500);
1277
1278   resolver_.reset(new HostResolverImpl(DefaultOptions(), NULL));
1279   resolver_->set_proc_params_for_test(params);
1280
1281   // Resolve "host1".
1282   HostResolver::RequestInfo info(HostPortPair("host1", 70));
1283   Request* req = CreateRequest(info, DEFAULT_PRIORITY);
1284   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1285
1286   // Resolve returns -4 to indicate that 3rd attempt has resolved the host.
1287   EXPECT_EQ(-4, req->WaitForResult());
1288
1289   resolver_proc->WaitForAllAttemptsToFinish(
1290       base::TimeDelta::FromMilliseconds(60000));
1291   base::MessageLoop::current()->RunUntilIdle();
1292
1293   EXPECT_EQ(resolver_proc->total_attempts_resolved(), kTotalAttempts);
1294   EXPECT_EQ(resolver_proc->resolved_attempt_number(), kAttemptNumberToResolve);
1295 }
1296
1297 DnsConfig CreateValidDnsConfig() {
1298   IPAddressNumber dns_ip;
1299   bool rv = ParseIPLiteralToNumber("192.168.1.0", &dns_ip);
1300   EXPECT_TRUE(rv);
1301
1302   DnsConfig config;
1303   config.nameservers.push_back(IPEndPoint(dns_ip, dns_protocol::kDefaultPort));
1304   EXPECT_TRUE(config.IsValid());
1305   return config;
1306 }
1307
1308 // Specialized fixture for tests of DnsTask.
1309 class HostResolverImplDnsTest : public HostResolverImplTest {
1310  public:
1311   HostResolverImplDnsTest() : dns_client_(NULL) {}
1312
1313  protected:
1314   // testing::Test implementation:
1315   virtual void SetUp() OVERRIDE {
1316     AddDnsRule("nx", dns_protocol::kTypeA, MockDnsClientRule::FAIL, false);
1317     AddDnsRule("nx", dns_protocol::kTypeAAAA, MockDnsClientRule::FAIL, false);
1318     AddDnsRule("ok", dns_protocol::kTypeA, MockDnsClientRule::OK, false);
1319     AddDnsRule("ok", dns_protocol::kTypeAAAA, MockDnsClientRule::OK, false);
1320     AddDnsRule("4ok", dns_protocol::kTypeA, MockDnsClientRule::OK, false);
1321     AddDnsRule("4ok", dns_protocol::kTypeAAAA, MockDnsClientRule::EMPTY, false);
1322     AddDnsRule("6ok", dns_protocol::kTypeA, MockDnsClientRule::EMPTY, false);
1323     AddDnsRule("6ok", dns_protocol::kTypeAAAA, MockDnsClientRule::OK, false);
1324     AddDnsRule("4nx", dns_protocol::kTypeA, MockDnsClientRule::OK, false);
1325     AddDnsRule("4nx", dns_protocol::kTypeAAAA, MockDnsClientRule::FAIL, false);
1326     AddDnsRule("empty", dns_protocol::kTypeA, MockDnsClientRule::EMPTY, false);
1327     AddDnsRule("empty", dns_protocol::kTypeAAAA, MockDnsClientRule::EMPTY,
1328                false);
1329
1330     AddDnsRule("slow_nx", dns_protocol::kTypeA, MockDnsClientRule::FAIL, true);
1331     AddDnsRule("slow_nx", dns_protocol::kTypeAAAA, MockDnsClientRule::FAIL,
1332                true);
1333
1334     AddDnsRule("4slow_ok", dns_protocol::kTypeA, MockDnsClientRule::OK, true);
1335     AddDnsRule("4slow_ok", dns_protocol::kTypeAAAA, MockDnsClientRule::OK,
1336                false);
1337     AddDnsRule("6slow_ok", dns_protocol::kTypeA, MockDnsClientRule::OK, false);
1338     AddDnsRule("6slow_ok", dns_protocol::kTypeAAAA, MockDnsClientRule::OK,
1339                true);
1340     AddDnsRule("4slow_4ok", dns_protocol::kTypeA, MockDnsClientRule::OK, true);
1341     AddDnsRule("4slow_4ok", dns_protocol::kTypeAAAA, MockDnsClientRule::EMPTY,
1342                false);
1343     AddDnsRule("4slow_4timeout", dns_protocol::kTypeA,
1344                MockDnsClientRule::TIMEOUT, true);
1345     AddDnsRule("4slow_4timeout", dns_protocol::kTypeAAAA, MockDnsClientRule::OK,
1346                false);
1347     AddDnsRule("4slow_6timeout", dns_protocol::kTypeA,
1348                MockDnsClientRule::OK, true);
1349     AddDnsRule("4slow_6timeout", dns_protocol::kTypeAAAA,
1350                MockDnsClientRule::TIMEOUT, false);
1351     CreateResolver();
1352   }
1353
1354   // HostResolverImplTest implementation:
1355   virtual void CreateResolverWithLimitsAndParams(
1356       size_t max_concurrent_resolves,
1357       const HostResolverImpl::ProcTaskParams& params) OVERRIDE {
1358     HostResolverImpl::Options options = DefaultOptions();
1359     options.max_concurrent_resolves = max_concurrent_resolves;
1360     resolver_.reset(new HostResolverImpl(options, NULL));
1361     resolver_->set_proc_params_for_test(params);
1362     // Disable IPv6 support probing.
1363     resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1364     dns_client_ = new MockDnsClient(DnsConfig(), dns_rules_);
1365     resolver_->SetDnsClient(scoped_ptr<DnsClient>(dns_client_));
1366   }
1367
1368   // Adds a rule to |dns_rules_|. Must be followed by |CreateResolver| to apply.
1369   void AddDnsRule(const std::string& prefix,
1370                   uint16 qtype,
1371                   MockDnsClientRule::Result result,
1372                   bool delay) {
1373     dns_rules_.push_back(MockDnsClientRule(prefix, qtype, result, delay));
1374   }
1375
1376   void ChangeDnsConfig(const DnsConfig& config) {
1377     NetworkChangeNotifier::SetDnsConfig(config);
1378     // Notification is delivered asynchronously.
1379     base::MessageLoop::current()->RunUntilIdle();
1380   }
1381
1382   MockDnsClientRuleList dns_rules_;
1383   // Owned by |resolver_|.
1384   MockDnsClient* dns_client_;
1385 };
1386
1387 // TODO(szym): Test AbortAllInProgressJobs due to DnsConfig change.
1388
1389 // TODO(cbentzel): Test a mix of requests with different HostResolverFlags.
1390
1391 // Test successful and fallback resolutions in HostResolverImpl::DnsTask.
1392 TEST_F(HostResolverImplDnsTest, DnsTask) {
1393   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1394
1395   proc_->AddRuleForAllFamilies("nx_succeed", "192.168.1.102");
1396   // All other hostnames will fail in proc_.
1397
1398   // Initially there is no config, so client should not be invoked.
1399   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok_fail", 80)->Resolve());
1400   proc_->SignalMultiple(requests_.size());
1401
1402   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[0]->WaitForResult());
1403
1404   ChangeDnsConfig(CreateValidDnsConfig());
1405
1406   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok_fail", 80)->Resolve());
1407   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_fail", 80)->Resolve());
1408   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_succeed", 80)->Resolve());
1409
1410   proc_->SignalMultiple(requests_.size());
1411
1412   for (size_t i = 1; i < requests_.size(); ++i)
1413     EXPECT_NE(ERR_UNEXPECTED, requests_[i]->WaitForResult()) << i;
1414
1415   EXPECT_EQ(OK, requests_[1]->result());
1416   // Resolved by MockDnsClient.
1417   EXPECT_TRUE(requests_[1]->HasOneAddress("127.0.0.1", 80));
1418   // Fallback to ProcTask.
1419   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[2]->result());
1420   EXPECT_EQ(OK, requests_[3]->result());
1421   EXPECT_TRUE(requests_[3]->HasOneAddress("192.168.1.102", 80));
1422 }
1423
1424 // Test successful and failing resolutions in HostResolverImpl::DnsTask when
1425 // fallback to ProcTask is disabled.
1426 TEST_F(HostResolverImplDnsTest, NoFallbackToProcTask) {
1427   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1428   set_fallback_to_proctask(false);
1429
1430   proc_->AddRuleForAllFamilies("nx_succeed", "192.168.1.102");
1431   // All other hostnames will fail in proc_.
1432
1433   // Set empty DnsConfig.
1434   ChangeDnsConfig(DnsConfig());
1435   // Initially there is no config, so client should not be invoked.
1436   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok_fail", 80)->Resolve());
1437   // There is no config, so fallback to ProcTask must work.
1438   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_succeed", 80)->Resolve());
1439   proc_->SignalMultiple(requests_.size());
1440
1441   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[0]->WaitForResult());
1442   EXPECT_EQ(OK, requests_[1]->WaitForResult());
1443   EXPECT_TRUE(requests_[1]->HasOneAddress("192.168.1.102", 80));
1444
1445   ChangeDnsConfig(CreateValidDnsConfig());
1446
1447   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok_abort", 80)->Resolve());
1448   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_abort", 80)->Resolve());
1449
1450   // Simulate the case when the preference or policy has disabled the DNS client
1451   // causing AbortDnsTasks.
1452   resolver_->SetDnsClient(
1453       scoped_ptr<DnsClient>(new MockDnsClient(DnsConfig(), dns_rules_)));
1454   ChangeDnsConfig(CreateValidDnsConfig());
1455
1456   // First request is resolved by MockDnsClient, others should fail due to
1457   // disabled fallback to ProcTask.
1458   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok_fail", 80)->Resolve());
1459   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_fail", 80)->Resolve());
1460   proc_->SignalMultiple(requests_.size());
1461
1462   // Aborted due to Network Change.
1463   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[2]->WaitForResult());
1464   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[3]->WaitForResult());
1465   // Resolved by MockDnsClient.
1466   EXPECT_EQ(OK, requests_[4]->WaitForResult());
1467   EXPECT_TRUE(requests_[4]->HasOneAddress("127.0.0.1", 80));
1468   // Fallback to ProcTask is disabled.
1469   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[5]->WaitForResult());
1470 }
1471
1472 // Test behavior of OnDnsTaskFailure when Job is aborted.
1473 TEST_F(HostResolverImplDnsTest, OnDnsTaskFailureAbortedJob) {
1474   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1475   ChangeDnsConfig(CreateValidDnsConfig());
1476   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_abort", 80)->Resolve());
1477   // Abort all jobs here.
1478   CreateResolver();
1479   proc_->SignalMultiple(requests_.size());
1480   // Run to completion.
1481   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
1482   // It shouldn't crash during OnDnsTaskFailure callbacks.
1483   EXPECT_EQ(ERR_IO_PENDING, requests_[0]->result());
1484
1485   // Repeat test with Fallback to ProcTask disabled
1486   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1487   set_fallback_to_proctask(false);
1488   ChangeDnsConfig(CreateValidDnsConfig());
1489   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("nx_abort", 80)->Resolve());
1490   // Abort all jobs here.
1491   CreateResolver();
1492   // Run to completion.
1493   base::MessageLoop::current()->RunUntilIdle();  // Notification happens async.
1494   // It shouldn't crash during OnDnsTaskFailure callbacks.
1495   EXPECT_EQ(ERR_IO_PENDING, requests_[1]->result());
1496 }
1497
1498 TEST_F(HostResolverImplDnsTest, DnsTaskUnspec) {
1499   ChangeDnsConfig(CreateValidDnsConfig());
1500
1501   proc_->AddRuleForAllFamilies("4nx", "192.168.1.101");
1502   // All other hostnames will fail in proc_.
1503
1504   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1505   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4ok", 80)->Resolve());
1506   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("6ok", 80)->Resolve());
1507   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4nx", 80)->Resolve());
1508
1509   proc_->SignalMultiple(requests_.size());
1510
1511   for (size_t i = 0; i < requests_.size(); ++i)
1512     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1513
1514   EXPECT_EQ(2u, requests_[0]->NumberOfAddresses());
1515   EXPECT_TRUE(requests_[0]->HasAddress("127.0.0.1", 80));
1516   EXPECT_TRUE(requests_[0]->HasAddress("::1", 80));
1517   EXPECT_EQ(1u, requests_[1]->NumberOfAddresses());
1518   EXPECT_TRUE(requests_[1]->HasAddress("127.0.0.1", 80));
1519   EXPECT_EQ(1u, requests_[2]->NumberOfAddresses());
1520   EXPECT_TRUE(requests_[2]->HasAddress("::1", 80));
1521   EXPECT_EQ(1u, requests_[3]->NumberOfAddresses());
1522   EXPECT_TRUE(requests_[3]->HasAddress("192.168.1.101", 80));
1523 }
1524
1525 TEST_F(HostResolverImplDnsTest, ServeFromHosts) {
1526   // Initially, use empty HOSTS file.
1527   DnsConfig config = CreateValidDnsConfig();
1528   ChangeDnsConfig(config);
1529
1530   proc_->AddRuleForAllFamilies(std::string(),
1531                                std::string());  // Default to failures.
1532   proc_->SignalMultiple(1u);  // For the first request which misses.
1533
1534   Request* req0 = CreateRequest("nx_ipv4", 80);
1535   EXPECT_EQ(ERR_IO_PENDING, req0->Resolve());
1536   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req0->WaitForResult());
1537
1538   IPAddressNumber local_ipv4, local_ipv6;
1539   ASSERT_TRUE(ParseIPLiteralToNumber("127.0.0.1", &local_ipv4));
1540   ASSERT_TRUE(ParseIPLiteralToNumber("::1", &local_ipv6));
1541
1542   DnsHosts hosts;
1543   hosts[DnsHostsKey("nx_ipv4", ADDRESS_FAMILY_IPV4)] = local_ipv4;
1544   hosts[DnsHostsKey("nx_ipv6", ADDRESS_FAMILY_IPV6)] = local_ipv6;
1545   hosts[DnsHostsKey("nx_both", ADDRESS_FAMILY_IPV4)] = local_ipv4;
1546   hosts[DnsHostsKey("nx_both", ADDRESS_FAMILY_IPV6)] = local_ipv6;
1547
1548   // Update HOSTS file.
1549   config.hosts = hosts;
1550   ChangeDnsConfig(config);
1551
1552   Request* req1 = CreateRequest("nx_ipv4", 80);
1553   EXPECT_EQ(OK, req1->Resolve());
1554   EXPECT_TRUE(req1->HasOneAddress("127.0.0.1", 80));
1555
1556   Request* req2 = CreateRequest("nx_ipv6", 80);
1557   EXPECT_EQ(OK, req2->Resolve());
1558   EXPECT_TRUE(req2->HasOneAddress("::1", 80));
1559
1560   Request* req3 = CreateRequest("nx_both", 80);
1561   EXPECT_EQ(OK, req3->Resolve());
1562   EXPECT_TRUE(req3->HasAddress("127.0.0.1", 80) &&
1563               req3->HasAddress("::1", 80));
1564
1565   // Requests with specified AddressFamily.
1566   Request* req4 = CreateRequest("nx_ipv4", 80, MEDIUM, ADDRESS_FAMILY_IPV4);
1567   EXPECT_EQ(OK, req4->Resolve());
1568   EXPECT_TRUE(req4->HasOneAddress("127.0.0.1", 80));
1569
1570   Request* req5 = CreateRequest("nx_ipv6", 80, MEDIUM, ADDRESS_FAMILY_IPV6);
1571   EXPECT_EQ(OK, req5->Resolve());
1572   EXPECT_TRUE(req5->HasOneAddress("::1", 80));
1573
1574   // Request with upper case.
1575   Request* req6 = CreateRequest("nx_IPV4", 80);
1576   EXPECT_EQ(OK, req6->Resolve());
1577   EXPECT_TRUE(req6->HasOneAddress("127.0.0.1", 80));
1578 }
1579
1580 TEST_F(HostResolverImplDnsTest, BypassDnsTask) {
1581   ChangeDnsConfig(CreateValidDnsConfig());
1582
1583   proc_->AddRuleForAllFamilies(std::string(),
1584                                std::string());  // Default to failures.
1585
1586   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok.local", 80)->Resolve());
1587   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok.local.", 80)->Resolve());
1588   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("oklocal", 80)->Resolve());
1589   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("oklocal.", 80)->Resolve());
1590   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1591
1592   proc_->SignalMultiple(requests_.size());
1593
1594   for (size_t i = 0; i < 2; ++i)
1595     EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[i]->WaitForResult()) << i;
1596
1597   for (size_t i = 2; i < requests_.size(); ++i)
1598     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1599 }
1600
1601 TEST_F(HostResolverImplDnsTest, SystemOnlyBypassesDnsTask) {
1602   ChangeDnsConfig(CreateValidDnsConfig());
1603
1604   proc_->AddRuleForAllFamilies(std::string(), std::string());
1605
1606   HostResolver::RequestInfo info_bypass(HostPortPair("ok", 80));
1607   info_bypass.set_host_resolver_flags(HOST_RESOLVER_SYSTEM_ONLY);
1608   EXPECT_EQ(ERR_IO_PENDING, CreateRequest(info_bypass, MEDIUM)->Resolve());
1609
1610   HostResolver::RequestInfo info(HostPortPair("ok", 80));
1611   EXPECT_EQ(ERR_IO_PENDING, CreateRequest(info, MEDIUM)->Resolve());
1612
1613   proc_->SignalMultiple(requests_.size());
1614
1615   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[0]->WaitForResult());
1616   EXPECT_EQ(OK, requests_[1]->WaitForResult());
1617 }
1618
1619 TEST_F(HostResolverImplDnsTest, DisableDnsClientOnPersistentFailure) {
1620   ChangeDnsConfig(CreateValidDnsConfig());
1621
1622   proc_->AddRuleForAllFamilies(std::string(),
1623                                std::string());  // Default to failures.
1624
1625   // Check that DnsTask works.
1626   Request* req = CreateRequest("ok_1", 80);
1627   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1628   EXPECT_EQ(OK, req->WaitForResult());
1629
1630   for (unsigned i = 0; i < maximum_dns_failures(); ++i) {
1631     // Use custom names to require separate Jobs.
1632     std::string hostname = base::StringPrintf("nx_%u", i);
1633     // Ensure fallback to ProcTask succeeds.
1634     proc_->AddRuleForAllFamilies(hostname, "192.168.1.101");
1635     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname, 80)->Resolve()) << i;
1636   }
1637
1638   proc_->SignalMultiple(requests_.size());
1639
1640   for (size_t i = 0; i < requests_.size(); ++i)
1641     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1642
1643   ASSERT_FALSE(proc_->HasBlockedRequests());
1644
1645   // DnsTask should be disabled by now.
1646   req = CreateRequest("ok_2", 80);
1647   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1648   proc_->SignalMultiple(1u);
1649   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->WaitForResult());
1650
1651   // Check that it is re-enabled after DNS change.
1652   ChangeDnsConfig(CreateValidDnsConfig());
1653   req = CreateRequest("ok_3", 80);
1654   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1655   EXPECT_EQ(OK, req->WaitForResult());
1656 }
1657
1658 TEST_F(HostResolverImplDnsTest, DontDisableDnsClientOnSporadicFailure) {
1659   ChangeDnsConfig(CreateValidDnsConfig());
1660
1661   // |proc_| defaults to successes.
1662
1663   // 20 failures interleaved with 20 successes.
1664   for (unsigned i = 0; i < 40; ++i) {
1665     // Use custom names to require separate Jobs.
1666     std::string hostname = (i % 2) == 0 ? base::StringPrintf("nx_%u", i)
1667                                         : base::StringPrintf("ok_%u", i);
1668     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname, 80)->Resolve()) << i;
1669   }
1670
1671   proc_->SignalMultiple(requests_.size());
1672
1673   for (size_t i = 0; i < requests_.size(); ++i)
1674     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
1675
1676   // Make |proc_| default to failures.
1677   proc_->AddRuleForAllFamilies(std::string(), std::string());
1678
1679   // DnsTask should still be enabled.
1680   Request* req = CreateRequest("ok_last", 80);
1681   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1682   EXPECT_EQ(OK, req->WaitForResult());
1683 }
1684
1685 // Confirm that resolving "localhost" is unrestricted even if there are no
1686 // global IPv6 address. See SystemHostResolverCall for rationale.
1687 // Test both the DnsClient and system host resolver paths.
1688 TEST_F(HostResolverImplDnsTest, DualFamilyLocalhost) {
1689   // Use regular SystemHostResolverCall!
1690   scoped_refptr<HostResolverProc> proc(new SystemHostResolverProc());
1691   resolver_.reset(new HostResolverImpl(DefaultOptions(), NULL));
1692   resolver_->set_proc_params_for_test(DefaultParams(proc.get()));
1693
1694   resolver_->SetDnsClient(
1695       scoped_ptr<DnsClient>(new MockDnsClient(DnsConfig(), dns_rules_)));
1696   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1697
1698   // Get the expected output.
1699   AddressList addrlist;
1700   int rv = proc->Resolve("localhost", ADDRESS_FAMILY_UNSPECIFIED, 0, &addrlist,
1701                          NULL);
1702   if (rv != OK)
1703     return;
1704
1705   for (unsigned i = 0; i < addrlist.size(); ++i)
1706     LOG(WARNING) << addrlist[i].ToString();
1707
1708   bool saw_ipv4 = AddressListContains(addrlist, "127.0.0.1", 0);
1709   bool saw_ipv6 = AddressListContains(addrlist, "::1", 0);
1710   if (!saw_ipv4 && !saw_ipv6)
1711     return;
1712
1713   HostResolver::RequestInfo info(HostPortPair("localhost", 80));
1714   info.set_address_family(ADDRESS_FAMILY_UNSPECIFIED);
1715   info.set_host_resolver_flags(HOST_RESOLVER_DEFAULT_FAMILY_SET_DUE_TO_NO_IPV6);
1716
1717   // Try without DnsClient.
1718   ChangeDnsConfig(DnsConfig());
1719   Request* req = CreateRequest(info, DEFAULT_PRIORITY);
1720   // It is resolved via getaddrinfo, so expect asynchronous result.
1721   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
1722   EXPECT_EQ(OK, req->WaitForResult());
1723
1724   EXPECT_EQ(saw_ipv4, req->HasAddress("127.0.0.1", 80));
1725   EXPECT_EQ(saw_ipv6, req->HasAddress("::1", 80));
1726
1727   // Configure DnsClient with dual-host HOSTS file.
1728   DnsConfig config = CreateValidDnsConfig();
1729   DnsHosts hosts;
1730   IPAddressNumber local_ipv4, local_ipv6;
1731   ASSERT_TRUE(ParseIPLiteralToNumber("127.0.0.1", &local_ipv4));
1732   ASSERT_TRUE(ParseIPLiteralToNumber("::1", &local_ipv6));
1733   if (saw_ipv4)
1734     hosts[DnsHostsKey("localhost", ADDRESS_FAMILY_IPV4)] = local_ipv4;
1735   if (saw_ipv6)
1736     hosts[DnsHostsKey("localhost", ADDRESS_FAMILY_IPV6)] = local_ipv6;
1737   config.hosts = hosts;
1738
1739   ChangeDnsConfig(config);
1740   req = CreateRequest(info, DEFAULT_PRIORITY);
1741   // Expect synchronous resolution from DnsHosts.
1742   EXPECT_EQ(OK, req->Resolve());
1743
1744   EXPECT_EQ(saw_ipv4, req->HasAddress("127.0.0.1", 80));
1745   EXPECT_EQ(saw_ipv6, req->HasAddress("::1", 80));
1746 }
1747
1748 // Cancel a request with a single DNS transaction active.
1749 TEST_F(HostResolverImplDnsTest, CancelWithOneTransactionActive) {
1750   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_IPV4);
1751   ChangeDnsConfig(CreateValidDnsConfig());
1752
1753   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1754   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1755   requests_[0]->Cancel();
1756
1757   // Dispatcher state checked in TearDown.
1758 }
1759
1760 // Cancel a request with a single DNS transaction active and another pending.
1761 TEST_F(HostResolverImplDnsTest, CancelWithOneTransactionActiveOnePending) {
1762   CreateSerialResolver();
1763   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1764   ChangeDnsConfig(CreateValidDnsConfig());
1765
1766   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1767   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1768   requests_[0]->Cancel();
1769
1770   // Dispatcher state checked in TearDown.
1771 }
1772
1773 // Cancel a request with two DNS transactions active.
1774 TEST_F(HostResolverImplDnsTest, CancelWithTwoTransactionsActive) {
1775   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1776   ChangeDnsConfig(CreateValidDnsConfig());
1777
1778   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1779   EXPECT_EQ(2u, num_running_dispatcher_jobs());
1780   requests_[0]->Cancel();
1781
1782   // Dispatcher state checked in TearDown.
1783 }
1784
1785 // Delete a resolver with some active requests and some queued requests.
1786 TEST_F(HostResolverImplDnsTest, DeleteWithActiveTransactions) {
1787   // At most 10 Jobs active at once.
1788   CreateResolverWithLimitsAndParams(10u, DefaultParams(proc_.get()));
1789
1790   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1791   ChangeDnsConfig(CreateValidDnsConfig());
1792
1793   // First active job is an IPv4 request.
1794   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80, MEDIUM,
1795                                           ADDRESS_FAMILY_IPV4)->Resolve());
1796
1797   // Add 10 more DNS lookups for different hostnames.  First 4 should have two
1798   // active jobs, next one has a single active job, and one pending.  Others
1799   // should all be queued.
1800   for (int i = 0; i < 10; ++i) {
1801     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(
1802         base::StringPrintf("ok%i", i))->Resolve());
1803   }
1804   EXPECT_EQ(10u, num_running_dispatcher_jobs());
1805
1806   resolver_.reset();
1807 }
1808
1809 // Cancel a request with only the IPv6 transaction active.
1810 TEST_F(HostResolverImplDnsTest, CancelWithIPv6TransactionActive) {
1811   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1812   ChangeDnsConfig(CreateValidDnsConfig());
1813
1814   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("6slow_ok", 80)->Resolve());
1815   EXPECT_EQ(2u, num_running_dispatcher_jobs());
1816
1817   // The IPv4 request should complete, the IPv6 request is still pending.
1818   base::RunLoop().RunUntilIdle();
1819   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1820   requests_[0]->Cancel();
1821
1822   // Dispatcher state checked in TearDown.
1823 }
1824
1825 // Cancel a request with only the IPv4 transaction pending.
1826 TEST_F(HostResolverImplDnsTest, CancelWithIPv4TransactionPending) {
1827   set_fallback_to_proctask(false);
1828   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1829   ChangeDnsConfig(CreateValidDnsConfig());
1830
1831   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4slow_ok", 80)->Resolve());
1832   EXPECT_EQ(2u, num_running_dispatcher_jobs());
1833
1834   // The IPv6 request should complete, the IPv4 request is still pending.
1835   base::RunLoop().RunUntilIdle();
1836   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1837
1838   requests_[0]->Cancel();
1839 }
1840
1841 // Test cases where AAAA completes first.
1842 TEST_F(HostResolverImplDnsTest, AAAACompletesFirst) {
1843   set_fallback_to_proctask(false);
1844   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1845   ChangeDnsConfig(CreateValidDnsConfig());
1846
1847   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4slow_ok", 80)->Resolve());
1848   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4slow_4ok", 80)->Resolve());
1849   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4slow_4timeout", 80)->Resolve());
1850   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("4slow_6timeout", 80)->Resolve());
1851
1852   base::RunLoop().RunUntilIdle();
1853   EXPECT_FALSE(requests_[0]->completed());
1854   EXPECT_FALSE(requests_[1]->completed());
1855   EXPECT_FALSE(requests_[2]->completed());
1856   // The IPv6 of the third request should have failed and resulted in cancelling
1857   // the IPv4 request.
1858   EXPECT_TRUE(requests_[3]->completed());
1859   EXPECT_EQ(ERR_DNS_TIMED_OUT, requests_[3]->result());
1860   EXPECT_EQ(3u, num_running_dispatcher_jobs());
1861
1862   dns_client_->CompleteDelayedTransactions();
1863   EXPECT_TRUE(requests_[0]->completed());
1864   EXPECT_EQ(OK, requests_[0]->result());
1865   EXPECT_EQ(2u, requests_[0]->NumberOfAddresses());
1866   EXPECT_TRUE(requests_[0]->HasAddress("127.0.0.1", 80));
1867   EXPECT_TRUE(requests_[0]->HasAddress("::1", 80));
1868
1869   EXPECT_TRUE(requests_[1]->completed());
1870   EXPECT_EQ(OK, requests_[1]->result());
1871   EXPECT_EQ(1u, requests_[1]->NumberOfAddresses());
1872   EXPECT_TRUE(requests_[1]->HasAddress("127.0.0.1", 80));
1873
1874   EXPECT_TRUE(requests_[2]->completed());
1875   EXPECT_EQ(ERR_DNS_TIMED_OUT, requests_[2]->result());
1876 }
1877
1878 // Test the case where only a single transaction slot is available.
1879 TEST_F(HostResolverImplDnsTest, SerialResolver) {
1880   CreateSerialResolver();
1881   set_fallback_to_proctask(false);
1882   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1883   ChangeDnsConfig(CreateValidDnsConfig());
1884
1885   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
1886   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1887
1888   base::RunLoop().RunUntilIdle();
1889   EXPECT_TRUE(requests_[0]->completed());
1890   EXPECT_EQ(OK, requests_[0]->result());
1891   EXPECT_EQ(2u, requests_[0]->NumberOfAddresses());
1892   EXPECT_TRUE(requests_[0]->HasAddress("127.0.0.1", 80));
1893   EXPECT_TRUE(requests_[0]->HasAddress("::1", 80));
1894 }
1895
1896 // Test the case where the AAAA query is started when another transaction
1897 // completes.
1898 TEST_F(HostResolverImplDnsTest, AAAAStartsAfterOtherJobFinishes) {
1899   CreateResolverWithLimitsAndParams(2u, DefaultParams(proc_.get()));
1900   set_fallback_to_proctask(false);
1901   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1902   ChangeDnsConfig(CreateValidDnsConfig());
1903
1904   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80, MEDIUM,
1905                                           ADDRESS_FAMILY_IPV4)->Resolve());
1906   EXPECT_EQ(ERR_IO_PENDING,
1907             CreateRequest("4slow_ok", 80, MEDIUM)->Resolve());
1908   // An IPv4 request should have been started pending for each job.
1909   EXPECT_EQ(2u, num_running_dispatcher_jobs());
1910
1911   // Request 0's IPv4 request should complete, starting Request 1's IPv6
1912   // request, which should also complete.
1913   base::RunLoop().RunUntilIdle();
1914   EXPECT_EQ(1u, num_running_dispatcher_jobs());
1915   EXPECT_TRUE(requests_[0]->completed());
1916   EXPECT_FALSE(requests_[1]->completed());
1917
1918   dns_client_->CompleteDelayedTransactions();
1919   EXPECT_TRUE(requests_[1]->completed());
1920   EXPECT_EQ(OK, requests_[1]->result());
1921   EXPECT_EQ(2u, requests_[1]->NumberOfAddresses());
1922   EXPECT_TRUE(requests_[1]->HasAddress("127.0.0.1", 80));
1923   EXPECT_TRUE(requests_[1]->HasAddress("::1", 80));
1924 }
1925
1926 // Tests the case that a Job with a single transaction receives an empty address
1927 // list, triggering fallback to ProcTask.
1928 TEST_F(HostResolverImplDnsTest, IPv4EmptyFallback) {
1929   ChangeDnsConfig(CreateValidDnsConfig());
1930   proc_->AddRuleForAllFamilies("empty_fallback", "192.168.0.1");
1931   proc_->SignalMultiple(1u);
1932   EXPECT_EQ(ERR_IO_PENDING,
1933             CreateRequest("empty_fallback", 80, MEDIUM,
1934                           ADDRESS_FAMILY_IPV4)->Resolve());
1935   EXPECT_EQ(OK, requests_[0]->WaitForResult());
1936   EXPECT_TRUE(requests_[0]->HasOneAddress("192.168.0.1", 80));
1937 }
1938
1939 // Tests the case that a Job with two transactions receives two empty address
1940 // lists, triggering fallback to ProcTask.
1941 TEST_F(HostResolverImplDnsTest, UnspecEmptyFallback) {
1942   ChangeDnsConfig(CreateValidDnsConfig());
1943   proc_->AddRuleForAllFamilies("empty_fallback", "192.168.0.1");
1944   proc_->SignalMultiple(1u);
1945   EXPECT_EQ(ERR_IO_PENDING,
1946             CreateRequest("empty_fallback", 80, MEDIUM,
1947                           ADDRESS_FAMILY_UNSPECIFIED)->Resolve());
1948   EXPECT_EQ(OK, requests_[0]->WaitForResult());
1949   EXPECT_TRUE(requests_[0]->HasOneAddress("192.168.0.1", 80));
1950 }
1951
1952 // Tests getting a new invalid DnsConfig while there are active DnsTasks.
1953 TEST_F(HostResolverImplDnsTest, InvalidDnsConfigWithPendingRequests) {
1954   // At most 3 jobs active at once.  This number is important, since we want to
1955   // make sure that aborting the first HostResolverImpl::Job does not trigger
1956   // another DnsTransaction on the second Job when it releases its second
1957   // prioritized dispatcher slot.
1958   CreateResolverWithLimitsAndParams(3u, DefaultParams(proc_.get()));
1959
1960   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
1961   ChangeDnsConfig(CreateValidDnsConfig());
1962
1963   proc_->AddRuleForAllFamilies("slow_nx1", "192.168.0.1");
1964   proc_->AddRuleForAllFamilies("slow_nx2", "192.168.0.2");
1965   proc_->AddRuleForAllFamilies("ok", "192.168.0.3");
1966
1967   // First active job gets two slots.
1968   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_nx1")->Resolve());
1969   // Next job gets one slot, and waits on another.
1970   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_nx2")->Resolve());
1971   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok")->Resolve());
1972
1973   EXPECT_EQ(3u, num_running_dispatcher_jobs());
1974
1975   // Clear DNS config.  Two in-progress jobs should be aborted, and the next one
1976   // should use a ProcTask.
1977   ChangeDnsConfig(DnsConfig());
1978   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[0]->WaitForResult());
1979   EXPECT_EQ(ERR_NETWORK_CHANGED, requests_[1]->WaitForResult());
1980
1981   // Finish up the third job.  Should bypass the DnsClient, and get its results
1982   // from MockHostResolverProc.
1983   EXPECT_FALSE(requests_[2]->completed());
1984   proc_->SignalMultiple(1u);
1985   EXPECT_EQ(OK, requests_[2]->WaitForResult());
1986   EXPECT_TRUE(requests_[2]->HasOneAddress("192.168.0.3", 80));
1987 }
1988
1989 // Tests the case that DnsClient is automatically disabled due to failures
1990 // while there are active DnsTasks.
1991 TEST_F(HostResolverImplDnsTest,
1992        AutomaticallyDisableDnsClientWithPendingRequests) {
1993   // Trying different limits is important for this test:  Different limits
1994   // result in different behavior when aborting in-progress DnsTasks.  Having
1995   // a DnsTask that has one job active and one in the queue when another job
1996   // occupying two slots has its DnsTask aborted is the case most likely to run
1997   // into problems.
1998   for (size_t limit = 1u; limit < 6u; ++limit) {
1999     CreateResolverWithLimitsAndParams(limit, DefaultParams(proc_.get()));
2000
2001     resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
2002     ChangeDnsConfig(CreateValidDnsConfig());
2003
2004     // Queue up enough failures to disable DnsTasks.  These will all fall back
2005     // to ProcTasks, and succeed there.
2006     for (unsigned i = 0u; i < maximum_dns_failures(); ++i) {
2007       std::string host = base::StringPrintf("nx%u", i);
2008       proc_->AddRuleForAllFamilies(host, "192.168.0.1");
2009       EXPECT_EQ(ERR_IO_PENDING, CreateRequest(host)->Resolve());
2010     }
2011
2012     // These requests should all bypass DnsTasks, due to the above failures,
2013     // so should end up using ProcTasks.
2014     proc_->AddRuleForAllFamilies("slow_ok1", "192.168.0.2");
2015     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_ok1")->Resolve());
2016     proc_->AddRuleForAllFamilies("slow_ok2", "192.168.0.3");
2017     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_ok2")->Resolve());
2018     proc_->AddRuleForAllFamilies("slow_ok3", "192.168.0.4");
2019     EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_ok3")->Resolve());
2020     proc_->SignalMultiple(maximum_dns_failures() + 3);
2021
2022     for (size_t i = 0u; i < maximum_dns_failures(); ++i) {
2023       EXPECT_EQ(OK, requests_[i]->WaitForResult());
2024       EXPECT_TRUE(requests_[i]->HasOneAddress("192.168.0.1", 80));
2025     }
2026
2027     EXPECT_EQ(OK, requests_[maximum_dns_failures()]->WaitForResult());
2028     EXPECT_TRUE(requests_[maximum_dns_failures()]->HasOneAddress(
2029                     "192.168.0.2", 80));
2030     EXPECT_EQ(OK, requests_[maximum_dns_failures() + 1]->WaitForResult());
2031     EXPECT_TRUE(requests_[maximum_dns_failures() + 1]->HasOneAddress(
2032                     "192.168.0.3", 80));
2033     EXPECT_EQ(OK, requests_[maximum_dns_failures() + 2]->WaitForResult());
2034     EXPECT_TRUE(requests_[maximum_dns_failures() + 2]->HasOneAddress(
2035                     "192.168.0.4", 80));
2036     requests_.clear();
2037   }
2038 }
2039
2040 // Tests a call to SetDnsClient while there are active DnsTasks.
2041 TEST_F(HostResolverImplDnsTest, ManuallyDisableDnsClientWithPendingRequests) {
2042   // At most 3 jobs active at once.  This number is important, since we want to
2043   // make sure that aborting the first HostResolverImpl::Job does not trigger
2044   // another DnsTransaction on the second Job when it releases its second
2045   // prioritized dispatcher slot.
2046   CreateResolverWithLimitsAndParams(3u, DefaultParams(proc_.get()));
2047
2048   resolver_->SetDefaultAddressFamily(ADDRESS_FAMILY_UNSPECIFIED);
2049   ChangeDnsConfig(CreateValidDnsConfig());
2050
2051   proc_->AddRuleForAllFamilies("slow_ok1", "192.168.0.1");
2052   proc_->AddRuleForAllFamilies("slow_ok2", "192.168.0.2");
2053   proc_->AddRuleForAllFamilies("ok", "192.168.0.3");
2054
2055   // First active job gets two slots.
2056   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_ok1")->Resolve());
2057   // Next job gets one slot, and waits on another.
2058   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("slow_ok2")->Resolve());
2059   // Next one is queued.
2060   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok")->Resolve());
2061
2062   EXPECT_EQ(3u, num_running_dispatcher_jobs());
2063
2064   // Clear DnsClient.  The two in-progress jobs should fall back to a ProcTask,
2065   // and the next one should be started with a ProcTask.
2066   resolver_->SetDnsClient(scoped_ptr<DnsClient>());
2067
2068   // All three in-progress requests should now be running a ProcTask.
2069   EXPECT_EQ(3u, num_running_dispatcher_jobs());
2070   proc_->SignalMultiple(3u);
2071
2072   EXPECT_EQ(OK, requests_[0]->WaitForResult());
2073   EXPECT_TRUE(requests_[0]->HasOneAddress("192.168.0.1", 80));
2074   EXPECT_EQ(OK, requests_[1]->WaitForResult());
2075   EXPECT_TRUE(requests_[1]->HasOneAddress("192.168.0.2", 80));
2076   EXPECT_EQ(OK, requests_[2]->WaitForResult());
2077   EXPECT_TRUE(requests_[2]->HasOneAddress("192.168.0.3", 80));
2078 }
2079
2080 }  // namespace net