mutex.hpp 4.18 KB
Newer Older
Martin Sustrik's avatar
Martin Sustrik committed
1
/*
2
    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
Martin Sustrik's avatar
Martin Sustrik committed
3

4
    This file is part of libzmq, the ZeroMQ core engine in C++.
Martin Sustrik's avatar
Martin Sustrik committed
5

6 7 8
    libzmq is free software; you can redistribute it and/or modify it under
    the terms of the GNU Lesser General Public License (LGPL) as published
    by the Free Software Foundation; either version 3 of the License, or
Martin Sustrik's avatar
Martin Sustrik committed
9 10
    (at your option) any later version.

11 12 13 14 15 16 17 18 19 20 21 22 23 24
    As a special exception, the Contributors give you permission to link
    this library with independent modules to produce an executable,
    regardless of the license terms of these independent modules, and to
    copy and distribute the resulting executable under terms of your choice,
    provided that you also meet, for each linked independent module, the
    terms and conditions of the license of that module. An independent
    module is a module which is not derived from or based on this library.
    If you modify this library, you must extend this exception to your
    version of the library.

    libzmq is distributed in the hope that it will be useful, but WITHOUT
    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    License for more details.
Martin Sustrik's avatar
Martin Sustrik committed
25

26
    You should have received a copy of the GNU Lesser General Public License
Martin Sustrik's avatar
Martin Sustrik committed
27 28 29
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

Martin Sustrik's avatar
Martin Sustrik committed
30 31
#ifndef __ZMQ_MUTEX_HPP_INCLUDED__
#define __ZMQ_MUTEX_HPP_INCLUDED__
Martin Sustrik's avatar
Martin Sustrik committed
32 33 34 35 36

#include "err.hpp"

//  Mutex class encapsulates OS mutex in a platform-independent way.

Martin Sustrik's avatar
Martin Sustrik committed
37
#ifdef ZMQ_HAVE_WINDOWS
Martin Sustrik's avatar
Martin Sustrik committed
38 39 40

#include "windows.hpp"

Martin Sustrik's avatar
Martin Sustrik committed
41
namespace zmq
Martin Sustrik's avatar
Martin Sustrik committed
42
{
43 44 45 46 47 48
class mutex_t
{
  public:
    inline mutex_t () { InitializeCriticalSection (&cs); }

    inline ~mutex_t () { DeleteCriticalSection (&cs); }
Martin Sustrik's avatar
Martin Sustrik committed
49

50 51 52
    inline void lock () { EnterCriticalSection (&cs); }

    inline bool try_lock ()
Martin Sustrik's avatar
Martin Sustrik committed
53
    {
54 55 56 57
        return (TryEnterCriticalSection (&cs)) ? true : false;
    }

    inline void unlock () { LeaveCriticalSection (&cs); }
Martin Sustrik's avatar
Martin Sustrik committed
58

59 60 61 62 63 64 65 66 67
    inline CRITICAL_SECTION *get_cs () { return &cs; }

  private:
    CRITICAL_SECTION cs;

    //  Disable copy construction and assignment.
    mutex_t (const mutex_t &);
    void operator= (const mutex_t &);
};
Martin Sustrik's avatar
Martin Sustrik committed
68 69 70 71 72 73
}

#else

#include <pthread.h>

Martin Sustrik's avatar
Martin Sustrik committed
74
namespace zmq
Martin Sustrik's avatar
Martin Sustrik committed
75
{
76 77 78 79 80 81 82 83 84 85
class mutex_t
{
  public:
    inline mutex_t ()
    {
        int rc = pthread_mutexattr_init (&attr);
        posix_assert (rc);

        rc = pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
        posix_assert (rc);
86

87 88 89 90 91
        rc = pthread_mutex_init (&mutex, &attr);
        posix_assert (rc);
    }

    inline ~mutex_t ()
Martin Sustrik's avatar
Martin Sustrik committed
92
    {
93 94
        int rc = pthread_mutex_destroy (&mutex);
        posix_assert (rc);
95

96 97 98
        rc = pthread_mutexattr_destroy (&attr);
        posix_assert (rc);
    }
Martin Sustrik's avatar
Martin Sustrik committed
99

100 101 102 103 104 105 106 107 108 109 110
    inline void lock ()
    {
        int rc = pthread_mutex_lock (&mutex);
        posix_assert (rc);
    }

    inline bool try_lock ()
    {
        int rc = pthread_mutex_trylock (&mutex);
        if (rc == EBUSY)
            return false;
Martin Sustrik's avatar
Martin Sustrik committed
111

112 113 114
        posix_assert (rc);
        return true;
    }
115

116
    inline void unlock ()
117
    {
118 119 120
        int rc = pthread_mutex_unlock (&mutex);
        posix_assert (rc);
    }
121

122
    inline pthread_mutex_t *get_mutex () { return &mutex; }
123

124 125 126
  private:
    pthread_mutex_t mutex;
    pthread_mutexattr_t attr;
127

128 129 130 131 132
    // Disable copy construction and assignment.
    mutex_t (const mutex_t &);
    const mutex_t &operator= (const mutex_t &);
};
}
133

134
#endif
135 136


137 138 139 140 141
namespace zmq
{
struct scoped_lock_t
{
    scoped_lock_t (mutex_t &mutex_) : mutex (mutex_) { mutex.lock (); }
142

143
    ~scoped_lock_t () { mutex.unlock (); }
144

145 146
  private:
    mutex_t &mutex;
147

148 149 150 151
    // Disable copy construction and assignment.
    scoped_lock_t (const scoped_lock_t &);
    const scoped_lock_t &operator= (const scoped_lock_t &);
};
152 153


154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169
struct scoped_optional_lock_t
{
    scoped_optional_lock_t (mutex_t *mutex_) : mutex (mutex_)
    {
        if (mutex != NULL)
            mutex->lock ();
    }

    ~scoped_optional_lock_t ()
    {
        if (mutex != NULL)
            mutex->unlock ();
    }

  private:
    mutex_t *mutex;
170

171 172 173 174
    // Disable copy construction and assignment.
    scoped_optional_lock_t (const scoped_lock_t &);
    const scoped_optional_lock_t &operator= (const scoped_lock_t &);
};
175 176
}

Martin Sustrik's avatar
Martin Sustrik committed
177
#endif