summaryrefslogtreecommitdiff
path: root/mutex.c
blob: 6d425abebf81752f93e089bdd520875822b43458 (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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*
 * mutex.c
 *
 * Description:
 * This translation unit implements mutual exclusion (mutex) primitives.
 */

#include "pthread.h"
#include "implement.h"

static int
insert_attr(pthread_mutexattr_t *attr)
{
  /* Add this attribute object to a list. */

  /* FIXME: implement using some dynamic scheme. */
  return 0;
}

static int
is_attr(pthread_mutexattr_t *attr)
{
  /* Return 0 if present, 1 otherwise. */

  /* FIXME: implement. For now, pretend the attribute is always okay, unless
     it is NULL. */

  return (attr == NULL) ? 1 : 0;
}

static int
remove_attr(pthread_mutexattr_t *attr)
{
  /* Remove this attribute object from the list. */

  /* FIXME: implement. */
  return 0;
}

int
pthread_mutex_init(pthread_mutex_t *mutex, pthread_mutex_attr_t *attr)
{
  if (mutex == NULL)
    {
      return EINVAL;
    }

  /* Create a critical section. */
  InitializeCriticalSection(mutex);

  return 0;
}

int
pthread_mutex_destroy(pthread_mutex_t *mutex)
{
  if (mutex == NULL)
    {
      return EINVAL;
    }

  DeleteCriticalSection(mutex);
  return 0;
}

int
pthread_mutexattr_init(pthread_mutexattr_t *attr)
{
  if (attr == NULL)
    {
      /* This is disallowed. */
      return EINVAL;
    }

  /* None of the optional attributes are supported yet. */
  return 0;
}

int
pthread_mutexattr_destroy(pthread_mutexattr_t *attr)
{
  /* Nothing to do. */
  return 0;
}

int
pthread_mutexattr_setpshared(pthread_mutexattr_t *attr, int process_shared)
{
  /* This function is not supported. */
  return ENOSYS;
}

int
pthread_mutexattr_getpshared(const pthread_mutexattr_t *attr,
			     int *process_shared)
{
  /* This function is not supported. */
  return ENOSYS;
}
  
int
pthread_mutexattr_setprotocol(pthread_mutexattr_t *attr,
			      int protocol)
{
  /* This function is not supported. */
  return ENOSYS;
}

int
pthread_mutexattr_getprotocol(const pthread_mutexattr_t *attr,
			     int *protocol)
{
  /* This function is not supported. */
  return ENOSYS;
}

int
pthread_mutexattr_setprioceiling(pthread_mutexattr_t *attr,
				 int ceiling)
{
  /* This function is not supported. */
  return ENOSYS;
}

int
pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *attr,
				 int *ceiling)
{
  /* This function is not supported. */
  return ENOSYS;
}

int
pthread_mutex_lock(pthread_mutex_t *mutex)
{
  EnterCriticalSection(mutex);
  return 0;
}

int
pthread_mutex_unlock(pthread_mutex_t *mutex)
{
  LeaveCriticalSection(mutex);
  return 0;
}

int
pthread_mutex_trylock(pthread_mutex_t *mutex)
{
  /* This only works on Windows NT 4.0 and above.  If this function is
     called from Windows 95, we must return ENOSYS. */
     
  if (mutex == NULL)
    {
      return EINVAL;
    }

  return (TryEnterCriticalSection(mutex) != TRUE) ? EBUSY : 0;
}