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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
|
/*
* Copyright (c) 2017 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
*/
#include <config.h>
#include <pthread.h>
#include <errno.h>
#include <parc/algol/parc_Object.h>
#include <parc/algol/parc_DisplayIndented.h>
#include <parc/concurrent/parc_Lock.h>
struct PARCLock {
pthread_mutex_t lock;
pthread_mutexattr_t lockAttributes;
pthread_cond_t notification;
bool locked;
bool notified;
};
static void
_parcLock_Finalize(PARCLock **instancePtr)
{
parcAssertNotNull(instancePtr, "Parameter must be a non-null pointer to a PARCLock pointer.");
parcLock_OptionalAssertValid(*instancePtr);
/* cleanup the instance fields here */
}
parcObject_ImplementAcquire(parcLock, PARCLock);
parcObject_ImplementRelease(parcLock, PARCLock);
parcObject_ExtendPARCObject(PARCLock, _parcLock_Finalize, NULL, parcLock_ToString, NULL, NULL, NULL, NULL);
void
parcLock_AssertValid(const PARCLock *instance)
{
parcAssertTrue(parcLock_IsValid(instance),
"PARCLock is not valid.");
}
PARCLock *
parcLock_Create(void)
{
PARCLock *result = parcObject_CreateInstance(PARCLock);
pthread_mutexattr_init(&result->lockAttributes);
pthread_mutexattr_settype(&result->lockAttributes, PTHREAD_MUTEX_ERRORCHECK);
pthread_mutex_init(&result->lock, &result->lockAttributes);
result->locked = false;
pthread_cond_init(&result->notification, NULL);
result->notified = false;
return result;
}
void
parcLock_Display(const PARCLock *lock, int indentation)
{
parcDisplayIndented_PrintLine(indentation, "PARCLock@%p {", lock);
parcDisplayIndented_PrintLine(indentation + 1, ".locked=%s", lock->locked ? "true" : "false");
parcDisplayIndented_PrintLine(indentation, "}");
}
bool
parcLock_IsValid(const PARCLock *instance)
{
bool result = false;
if (instance != NULL) {
result = true;
}
return result;
}
PARCBufferComposer *
parcLock_BuildString(const PARCLock *lock, PARCBufferComposer *composer)
{
parcBufferComposer_Format(composer, "lock{.state=%s }", lock->locked ? "true" : "false");
return composer;
}
char *
parcLock_ToString(const PARCLock *lock)
{
char *result = NULL;
PARCBufferComposer *composer = parcBufferComposer_Create();
if (composer != NULL) {
parcLock_BuildString(lock, composer);
result = parcBufferComposer_ToString(composer);
parcBufferComposer_Release(&composer);
}
return result;
}
bool
parcLock_Unlock(PARCLock *lock)
{
bool result = false;
parcLock_OptionalAssertValid(lock);
if (lock->locked) {
result = (pthread_mutex_unlock(&lock->lock) == 0);
}
return result;
}
bool
parcLock_Lock(PARCLock *lock)
{
bool result = false;
parcLock_OptionalAssertValid(lock);
int error = pthread_mutex_lock(&lock->lock);
if (error == 0) {
lock->locked = true;
result = true;
errno = 0;
} else {
errno = error;
}
return result;
}
bool
parcLock_TryLock(PARCLock *lock)
{
bool result = false;
parcLock_OptionalAssertValid(lock);
result = (pthread_mutex_trylock(&lock->lock) == 0);
if (result) {
lock->locked = true;
}
return result;
}
bool
parcLock_IsLocked(const PARCLock *lock)
{
parcLock_OptionalAssertValid(lock);
return lock->locked;
}
void
parcLock_Wait(PARCLock *lock)
{
parcLock_OptionalAssertValid(lock);
parcTrapUnexpectedStateIf(lock->locked == false,
"You must Lock the object before calling parcLock_Wait");
lock->notified = false;
while (lock->notified == false) {
pthread_cond_wait(&lock->notification, &lock->lock);
}
}
void
parcLock_Notify(PARCLock *lock)
{
parcLock_OptionalAssertValid(lock);
parcTrapUnexpectedStateIf(lock->locked == false,
"You must Lock the object before calling parcLock_Notify");
lock->notified = true;
pthread_cond_signal(&lock->notification);
}
|
