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
12namespace {
13
14class 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
40static base::LazyInstance<WinsockInitSingleton> g_winsock_init_singleton =
41    LAZY_INSTANCE_INITIALIZER;
42
43}  // namespace
44
45namespace net {
46
47void EnsureWinsockInit() {
48  g_winsock_init_singleton.Get();
49}
50
51}  // namespace net
52