1 /* 2 * Copyright (c) 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, msg); \ 36 } while (false) 37 38 #define assert_with_errno(cond, msg) check_with_errno(assert, cond, msg) 39 #define guarantee_with_errno(cond, msg) check_with_errno(guarantee, cond, msg) 40 41 PosixSemaphore::PosixSemaphore(uint value) { 42 int ret = sem_init(&_semaphore, 0, value); 43 44 guarantee_with_errno(ret == 0, "Failed to initialize semaphore"); 45 } 46 47 PosixSemaphore::~PosixSemaphore() { 48 sem_destroy(&_semaphore); 49 } 50 51 void PosixSemaphore::signal(uint count) { 52 for (uint i = 0; i < count; i++) { 53 int ret = sem_post(&_semaphore); 54 55 assert_with_errno(ret == 0, "sem_post failed"); 56 } 57 } 58 59 void PosixSemaphore::wait() { 60 int ret; 61 62 do { 63 ret = sem_wait(&_semaphore); 64 } while (ret != 0 && errno == EINTR); 65 66 assert_with_errno(ret == 0, "sem_wait failed"); 67 } 68 69 bool PosixSemaphore::trywait() { 70 int ret; 71 72 do { 73 ret = sem_trywait(&_semaphore); 74 } while (ret != 0 && errno == EINTR); 75 76 assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed"); 77 78 return ret == 0; 79 } 80 81 bool PosixSemaphore::timedwait(struct timespec ts) { 82 while (true) { 83 int result = sem_timedwait(&_semaphore, &ts); 84 if (result == 0) { 85 return true; 86 } else if (errno == EINTR) { 87 continue; 88 } else if (errno == ETIMEDOUT) { 89 return false; 90 } else { 91 assert_with_errno(false, "timedwait failed"); 92 return false; 93 } 94 } 95 } 96 #endif // __APPLE__ 97