Revert "Clean up dns prefetch code, and also port it."

chrome/browser/net/dns_slave.cc

+// Copyright (c) 2006-2008 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.
+
+// See header file for description of class
+
+#include <ws2tcpip.h>
+#include <Wspiapi.h>  // Needed for win2k compatibility
+
+#include "chrome/browser/net/dns_slave.h"
+
+#include "base/logging.h"
+#include "base/platform_thread.h"
+#include "base/string_util.h"
+#include "chrome/browser/net/dns_host_info.h"
+#include "chrome/browser/net/dns_master.h"
+
+
+namespace chrome_browser_net {
+
+//------------------------------------------------------------------------------
+// We supply a functions for stubbing network callbacks, so that offline testing
+// can be performed.
+//------------------------------------------------------------------------------
+static GetAddrInfoFunction get_addr = getaddrinfo;
+static FreeAddrInfoFunction free_addr = freeaddrinfo;
+void SetAddrinfoCallbacks(GetAddrInfoFunction getaddrinfo,
+                               FreeAddrInfoFunction freeaddrinfo) {
+  get_addr = getaddrinfo;
+  free_addr = freeaddrinfo;
+}
+
+GetAddrInfoFunction get_getaddrinfo() {return get_addr;}
+FreeAddrInfoFunction get_freeaddrinfo() {return free_addr;}
+
+
+//------------------------------------------------------------------------------
+// This is the entry method used by DnsMaster to start our thread.
+//------------------------------------------------------------------------------
+
+DWORD __stdcall DnsSlave::ThreadStart(void* pThis) {
+  DnsSlave* slave_instance = reinterpret_cast<DnsSlave*>(pThis);
+  return slave_instance->Run();
+}
+
+//------------------------------------------------------------------------------
+// The following are methods on the DnsPrefetch class.
+//------------------------------------------------------------------------------
+
+unsigned DnsSlave::Run() {
+  DCHECK(slave_index_ >= 0 && slave_index_ < DnsMaster::kSlaveCountMax);
+
+  std::string name = StringPrintf(
+      "dns_prefetcher_%d_of_%d", slave_index_ + 1, DnsMaster::kSlaveCountMax);
+  DLOG(INFO) << "Now Running " << name;
+  PlatformThread::SetName(name.c_str());
+
+  while (master_->GetNextAssignment(&hostname_)) {
+    BlockingDnsLookup();
+  }
+  // GetNextAssignment() fails when we are told to terminate.
+  master_->SetSlaveHasTerminated(slave_index_);
+  return 0;
+}
+
+void DnsSlave::BlockingDnsLookup() {
+  const char* port = "80";  // I may need to get the real port
+  addrinfo* result = NULL;
+
+  int error_code = get_addr(hostname_.c_str(), port, NULL, &result);
+
+  // Note that since info has value semantics, I need to ask
+  // master_ to set the new states atomically in its map.
+  switch (error_code) {
+    case 0:
+      master_->SetFoundState(hostname_);
+      break;
+
+    default:
+      DCHECK_EQ(0, error_code) << "surprising output" ;
+      // fall through
+
+    case WSAHOST_NOT_FOUND:
+      master_->SetNoSuchNameState(hostname_);
+      break;
+  }
+
+  // We don't save results, so lets free them...
+  if (result) {
+    free_addr(result);
+    result = NULL;
+  }
+}
+
+}  // namespace chrome_browser_net
+