1//
2// detail/impl/win_static_mutex.ipp
3// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4//
5// Copyright (c) 2003-2024 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6//
7// Distributed under the Boost Software License, Version 1.0. (See accompanying
8// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9//
10
11#ifndef BOOST_ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
12#define BOOST_ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
13
14#if defined(_MSC_VER) && (_MSC_VER >= 1200)
15# pragma once
16#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
17
18#include <boost/asio/detail/config.hpp>
19
20#if defined(BOOST_ASIO_WINDOWS)
21
22#include <cstdio>
23#include <boost/asio/detail/throw_error.hpp>
24#include <boost/asio/detail/win_static_mutex.hpp>
25#include <boost/asio/error.hpp>
26
27#include <boost/asio/detail/push_options.hpp>
28
29namespace boost {
30namespace asio {
31namespace detail {
32
33void win_static_mutex::init()
34{
35 int error = do_init();
36 boost::system::error_code ec(error,
37 boost::asio::error::get_system_category());
38 boost::asio::detail::throw_error(ec, "static_mutex");
39}
40
41int win_static_mutex::do_init()
42{
43 using namespace std; // For sprintf.
44 wchar_t mutex_name[128];
45#if defined(BOOST_ASIO_HAS_SECURE_RTL)
46 swprintf_s(
47#else // defined(BOOST_ASIO_HAS_SECURE_RTL)
48 _snwprintf(
49#endif // defined(BOOST_ASIO_HAS_SECURE_RTL)
50 mutex_name, 128, L"asio-58CCDC44-6264-4842-90C2-F3C545CB8AA7-%u-%p",
51 static_cast<unsigned int>(::GetCurrentProcessId()), this);
52
53#if defined(BOOST_ASIO_WINDOWS_APP)
54 HANDLE mutex = ::CreateMutexExW(0, mutex_name, CREATE_MUTEX_INITIAL_OWNER, 0);
55#else // defined(BOOST_ASIO_WINDOWS_APP)
56 HANDLE mutex = ::CreateMutexW(0, TRUE, mutex_name);
57#endif // defined(BOOST_ASIO_WINDOWS_APP)
58 DWORD last_error = ::GetLastError();
59 if (mutex == 0)
60 return ::GetLastError();
61
62 if (last_error == ERROR_ALREADY_EXISTS)
63 {
64#if defined(BOOST_ASIO_WINDOWS_APP)
65 ::WaitForSingleObjectEx(mutex, INFINITE, false);
66#else // defined(BOOST_ASIO_WINDOWS_APP)
67 ::WaitForSingleObject(mutex, INFINITE);
68#endif // defined(BOOST_ASIO_WINDOWS_APP)
69 }
70
71 if (initialised_)
72 {
73 ::ReleaseMutex(mutex);
74 ::CloseHandle(mutex);
75 return 0;
76 }
77
78#if defined(__MINGW32__)
79 // Not sure if MinGW supports structured exception handling, so for now
80 // we'll just call the Windows API and hope.
81# if defined(UNDER_CE)
82 ::InitializeCriticalSection(&crit_section_);
83# else
84 if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
85 {
86 last_error = ::GetLastError();
87 ::ReleaseMutex(mutex);
88 ::CloseHandle(mutex);
89 return last_error;
90 }
91# endif
92#else
93 __try
94 {
95# if defined(UNDER_CE)
96 ::InitializeCriticalSection(&crit_section_);
97# elif defined(BOOST_ASIO_WINDOWS_APP)
98 if (!::InitializeCriticalSectionEx(&crit_section_, 0, 0))
99 {
100 last_error = ::GetLastError();
101 ::ReleaseMutex(mutex);
102 ::CloseHandle(mutex);
103 return last_error;
104 }
105# else
106 if (!::InitializeCriticalSectionAndSpinCount(&crit_section_, 0x80000000))
107 {
108 last_error = ::GetLastError();
109 ::ReleaseMutex(mutex);
110 ::CloseHandle(mutex);
111 return last_error;
112 }
113# endif
114 }
115 __except(GetExceptionCode() == STATUS_NO_MEMORY
116 ? EXCEPTION_EXECUTE_HANDLER : EXCEPTION_CONTINUE_SEARCH)
117 {
118 ::ReleaseMutex(mutex);
119 ::CloseHandle(mutex);
120 return ERROR_OUTOFMEMORY;
121 }
122#endif
123
124 initialised_ = true;
125 ::ReleaseMutex(mutex);
126 ::CloseHandle(mutex);
127 return 0;
128}
129
130} // namespace detail
131} // namespace asio
132} // namespace boost
133
134#include <boost/asio/detail/pop_options.hpp>
135
136#endif // defined(BOOST_ASIO_WINDOWS)
137
138#endif // BOOST_ASIO_DETAIL_IMPL_WIN_STATIC_MUTEX_IPP
139

source code of boost/libs/asio/include/boost/asio/detail/impl/win_static_mutex.ipp