net/base/winsock_init.cc

   1 // Copyright (c) 2011 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 <winsock2.h>
   6
   7 #include "net/base/winsock_init.h"
   8
   9 #include "base/lazy_instance.h"
  10 #include "base/logging.h"
  11
  12 namespace {
  13
  14 class WinsockInitSingleton {
  15  public:
  16   WinsockInitSingleton() {
  17     WORD winsock_ver = MAKEWORD(2, 2);
  18     WSAData wsa_data;
  19     bool did_init = (WSAStartup(winsock_ver, &wsa_data) == 0);
  20     if (did_init) {
  21       DCHECK(wsa_data.wVersion == winsock_ver);
  22
  23       // The first time WSAGetLastError is called, the delay load helper will
  24       // resolve the address with GetProcAddress and fixup the import.  If a
  25       // third party application hooks system functions without correctly
  26       // restoring the error code, it is possible that the error code will be
  27       // overwritten during delay load resolution.  The result of the first
  28       // call may be incorrect, so make sure the function is bound and future
  29       // results will be correct.
  30       WSAGetLastError();
  31     }
  32   }
  33
  34   ~WinsockInitSingleton() {
  35     // Don't call WSACleanup() since the worker pool threads can continue to
  36     // call getaddrinfo() after Winsock has shutdown, which can lead to crashes.
  37   }
  38 };
  39
  40 static base::LazyInstance<WinsockInitSingleton> g_winsock_init_singleton =
  41     LAZY_INSTANCE_INITIALIZER;
  42
  43 }  // namespace
  44
  45 namespace net {
  46
  47 void EnsureWinsockInit() {
  48   g_winsock_init_singleton.Get();
  49 }
  50
  51 }  // namespace net