Fix crash on IP address change.

net/base/host_resolver_impl_unittest.cc

 // Copyright (c) 2010 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.
 
 #include "net/base/host_resolver_impl.h"
 
 #include <string>
 
 #include "base/compiler_specific.h"
 #include "base/message_loop.h"
@@ skipping 1025 matching lines @@
 
   EXPECT_EQ(2U, observer.start_log.size());
   EXPECT_EQ(0U, observer.finish_log.size());
   EXPECT_EQ(2U, observer.cancel_log.size());
 
   HostResolver::RequestInfo info("host2", 60);
   EXPECT_TRUE(observer.cancel_log[1] ==
               CapturingObserver::StartOrCancelEntry(1, info));
 }
 
+// Test that IP address changes flush the cache.
+TEST_F(HostResolverImplTest, FlushCacheOnIPAddressChange) {
+  MockNetworkChangeNotifier mock_network_change_notifier;
+  scoped_refptr<HostResolver> host_resolver(
+      new HostResolverImpl(NULL, CreateDefaultCache(),
+                           &mock_network_change_notifier,
+                           kMaxJobs));
+
+  AddressList addrlist;
+
+  // Resolve "host1".
+  HostResolver::RequestInfo info1("host1", 70);
+  TestCompletionCallback callback;
+  int rv = host_resolver->Resolve(info1, &addrlist, &callback, NULL, NULL);
+  EXPECT_EQ(ERR_IO_PENDING, rv);
+  EXPECT_EQ(OK, callback.WaitForResult());
+
+  // Resolve "host1" again -- this time it will be served from cache, but it
+  // should still notify of completion.
+  rv = host_resolver->Resolve(info1, &addrlist, &callback, NULL, NULL);
+  ASSERT_EQ(OK, rv);  // Should complete synchronously.
+
+  // Flush cache by triggering an IP address change.
+  mock_network_change_notifier.NotifyIPAddressChange();
+
+  // Resolve "host1" again -- this time it won't be served from cache, so it
+  // will complete asynchronously.
+  rv = host_resolver->Resolve(info1, &addrlist, &callback, NULL, NULL);
+  ASSERT_EQ(ERR_IO_PENDING, rv);  // Should complete asynchronously.
+  EXPECT_EQ(OK, callback.WaitForResult());
+}
+
 // Tests that when the maximum threads is set to 1, requests are dequeued
 // in order of priority.
 TEST_F(HostResolverImplTest, HigherPriorityRequestsStartedFirst) {
   scoped_refptr<CapturingHostResolverProc> resolver_proc =
       new CapturingHostResolverProc(NULL);
 
   // This HostResolverImpl will only allow 1 outstanding resolve at a time.
   size_t kMaxJobs = 1u;
   scoped_refptr<HostResolver> host_resolver(
       new HostResolverImpl(resolver_proc, CreateDefaultCache(),
@@ skipping 405 matching lines @@
   EXPECT_EQ("192.1.98.2", NetAddressToString(addrlist[1].head()));
   EXPECT_EQ("192.1.98.1", NetAddressToString(addrlist[2].head()));
   EXPECT_EQ("192.1.98.1", NetAddressToString(addrlist[3].head()));
 }
 
 // TODO(cbentzel): Test a mix of requests with different HostResolverFlags.
 
 }  // namespace
 
 }  // namespace net