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
|
/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* SPDX-License-Identifier: MPL-2.0
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, you can obtain one at https://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <isc/print.h>
#include <isc/rwlock.h>
#include <isc/string.h>
#include <isc/thread.h>
#include <isc/util.h>
#ifdef WIN32
#define sleep(x) Sleep(1000 * x)
#endif /* ifdef WIN32 */
isc_rwlock_t lock;
static isc_threadresult_t
#ifdef WIN32
WINAPI
#endif /* ifdef WIN32 */
run1(void *arg) {
char *message = arg;
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
printf("%s got READ lock\n", message);
sleep(1);
printf("%s giving up READ lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
printf("%s got READ lock\n", message);
sleep(1);
printf("%s giving up READ lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
printf("%s got WRITE lock\n", message);
sleep(1);
printf("%s giving up WRITE lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
return ((isc_threadresult_t)0);
}
static isc_threadresult_t
#ifdef WIN32
WINAPI
#endif /* ifdef WIN32 */
run2(void *arg) {
char *message = arg;
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
printf("%s got WRITE lock\n", message);
sleep(1);
printf("%s giving up WRITE lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
printf("%s got WRITE lock\n", message);
sleep(1);
printf("%s giving up WRITE lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_write) ==
ISC_R_SUCCESS);
RUNTIME_CHECK(isc_rwlock_lock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
printf("%s got READ lock\n", message);
sleep(1);
printf("%s giving up READ lock\n", message);
RUNTIME_CHECK(isc_rwlock_unlock(&lock, isc_rwlocktype_read) ==
ISC_R_SUCCESS);
return ((isc_threadresult_t)0);
}
int
main(int argc, char *argv[]) {
unsigned int nworkers;
unsigned int i;
isc_thread_t workers[100];
char name[100];
void *dupname;
if (argc > 1) {
nworkers = atoi(argv[1]);
} else {
nworkers = 2;
}
if (nworkers > 100) {
nworkers = 100;
}
printf("%u workers\n", nworkers);
isc_rwlock_init(&lock, 5, 10);
for (i = 0; i < nworkers; i++) {
snprintf(name, sizeof(name), "%02u", i);
dupname = strdup(name);
RUNTIME_CHECK(dupname != NULL);
if (i != 0 && i % 3 == 0) {
isc_thread_create(run1, dupname, &workers[i]);
} else {
isc_thread_create(run2, dupname, &workers[i]);
}
}
for (i = 0; i < nworkers; i++) {
isc_thread_join(workers[i], NULL);
}
isc_rwlock_destroy(&lock);
return (0);
}
|
