1/*
2 * Copyright (c) 2018, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled/precompiled.hpp"
26#ifndef __APPLE__
27#include "runtime/os.hpp"
28// POSIX unamed semaphores are not supported on OS X.
29#include "semaphore_posix.hpp"
30#include <semaphore.h>
31
32#define check_with_errno(check_type, cond, msg) \
33 do { \
34 int err = errno; \
35 check_type(cond, "%s; error='%s' (errno=%s)", msg, os::strerror(err), \
36 os::errno_name(err)); \
37} while (false)
38
39#define assert_with_errno(cond, msg) check_with_errno(assert, cond, msg)
40#define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg)
41
42PosixSemaphore::PosixSemaphore(uint value) {
43 int ret = sem_init(&_semaphore, 0, value);
44
45 guarantee_with_errno(ret == 0, "Failed to initialize semaphore");
46}
47
48PosixSemaphore::~PosixSemaphore() {
49 sem_destroy(&_semaphore);
50}
51
52void PosixSemaphore::signal(uint count) {
53 for (uint i = 0; i < count; i++) {
54 int ret = sem_post(&_semaphore);
55
56 assert_with_errno(ret == 0, "sem_post failed");
57 }
58}
59
60void PosixSemaphore::wait() {
61 int ret;
62
63 do {
64 ret = sem_wait(&_semaphore);
65 } while (ret != 0 && errno == EINTR);
66
67 assert_with_errno(ret == 0, "sem_wait failed");
68}
69
70bool PosixSemaphore::trywait() {
71 int ret;
72
73 do {
74 ret = sem_trywait(&_semaphore);
75 } while (ret != 0 && errno == EINTR);
76
77 assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed");
78
79 return ret == 0;
80}
81
82bool PosixSemaphore::timedwait(int64_t millis) {
83 struct timespec ts;
84 os::Posix::to_RTC_abstime(&ts, millis);
85 return timedwait(ts);
86}
87
88bool PosixSemaphore::timedwait(struct timespec ts) {
89 while (true) {
90 int result = sem_timedwait(&_semaphore, &ts);
91 if (result == 0) {
92 return true;
93 } else if (errno == EINTR) {
94 continue;
95 } else if (errno == ETIMEDOUT) {
96 return false;
97 } else {
98 assert_with_errno(false, "timedwait failed");
99 return false;
100 }
101 }
102}
103#endif // __APPLE__
104
105