summaryrefslogtreecommitdiff
path: root/server/src/mutex.cc
blob: d5e9a6f6d1ba8a32441a23a769b88cb2e3b48069 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set et sw=2 ts=2: */
/***************************************************************************
 *            mutex.cc
 *
 *  Thu Nov 12 10:51:32 CET 2009
 *  Copyright 2009 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of Pracro.
 *
 *  Pracro is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Pracro 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Pracro; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "mutex.h"

#define MUTEX_DBG(x)
//#define MUTEX_DBG(x) x

Mutex::Mutex()
{
  pthread_mutex_init (&mutex, NULL);
}

Mutex::~Mutex()
{
  pthread_mutex_destroy(&mutex);
}

bool Mutex::trylock()
{
  bool ret = pthread_mutex_trylock(&mutex) == 0;

  if(ret) MUTEX_DBG(printf("trylock succeeded on %s\n", name.c_str()));
  else MUTEX_DBG(printf("trylock failed on %s\n", name.c_str()));

  return ret;
}

void Mutex::lock()
{
  pthread_mutex_lock(&mutex);
  MUTEX_DBG(printf("lock on %s\n", name.c_str()));
}

void Mutex::unlock()
{
  MUTEX_DBG(printf("unlock on %s\n", name.c_str()));
  pthread_mutex_unlock(&mutex);
}


MutexAutolock::MutexAutolock(Mutex &m)
  : mutex(m)
{
  mutex.lock();
}

MutexAutolock::~MutexAutolock()
{
  mutex.unlock();
}

#ifdef TEST_MUTEX
//deps:
//cflags: $(PTHREAD_CFLAGS)
//libs: $(PTHREAD_LIBS)
#include <test.h>

#include <unistd.h>

volatile int cnt = 0;

static void* thread_run(void *data)
{
  Mutex *mutex = (Mutex*)data;
  mutex->lock();
  cnt++;
  mutex->unlock();
  return NULL;
}

TEST_BEGIN;

Mutex mutex;

mutex.lock();
TEST_FALSE(mutex.trylock(), "Testing if trylock works negative.");
mutex.unlock();
TEST_TRUE(mutex.trylock(), "Testing if trylock works positive.");
mutex.unlock();

mutex.lock();

pthread_attr_t attr;
pthread_t tid;
pthread_attr_init(&attr);
pthread_create(&tid, &attr, thread_run, &mutex);

sleep(1);
TEST_EQUAL_INT(cnt, 0, "Testing if lock prevent cnt from increasing.");
mutex.unlock();

sleep(1);
TEST_EQUAL_INT(cnt, 1, "Testing if unlock makes cnt increase.");

pthread_join(tid, NULL);
pthread_attr_destroy(&attr);

{
  TEST_TRUE(mutex.trylock(), "Testing if autolock has not yet locked the mutex.");
  mutex.unlock();
  MutexAutolock mlock(mutex);
  TEST_FALSE(mutex.trylock(), "Testing if autolock worked.");
}

TEST_TRUE(mutex.trylock(), "Testing if autolock has released the lock on the mutex.");
mutex.unlock();

TEST_END;

#endif/*TEST_MUTEX*/