jdk

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/*
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 * Copyright (c) 2018, 2022, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 *
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 */
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#include "precompiled.hpp"
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#ifndef __APPLE__
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#include "os_posix.hpp"
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#include "runtime/os.hpp"
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#include "utilities/debug.hpp"
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// POSIX unnamed semaphores are not supported on OS X.
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#include "semaphore_posix.hpp"
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#include <semaphore.h>
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PosixSemaphore::PosixSemaphore(uint value) {
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  int ret = sem_init(&_semaphore, 0, value);
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  guarantee_with_errno(ret == 0, "Failed to initialize semaphore");
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}
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PosixSemaphore::~PosixSemaphore() {
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  int ret = sem_destroy(&_semaphore);
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  assert_with_errno(ret == 0, "sem_destroy failed");
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}
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void PosixSemaphore::signal(uint count) {
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  for (uint i = 0; i < count; i++) {
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    int ret = sem_post(&_semaphore);
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    assert_with_errno(ret == 0, "sem_post failed");
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  }
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}
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void PosixSemaphore::wait() {
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  int ret;
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  do {
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    ret = sem_wait(&_semaphore);
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  } while (ret != 0 && errno == EINTR);
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  assert_with_errno(ret == 0, "sem_wait failed");
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}
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bool PosixSemaphore::trywait() {
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  int ret;
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  do {
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    ret = sem_trywait(&_semaphore);
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  } while (ret != 0 && errno == EINTR);
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  assert_with_errno(ret == 0 || errno == EAGAIN, "trywait failed");
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  return ret == 0;
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}
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bool PosixSemaphore::timedwait(int64_t millis) {
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  struct timespec ts;
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  os::Posix::to_RTC_abstime(&ts, millis);
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  return timedwait(ts);
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}
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bool PosixSemaphore::timedwait(struct timespec ts) {
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  while (true) {
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    int result = sem_timedwait(&_semaphore, &ts);
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    if (result == 0) {
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      return true;
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    } else if (errno == EINTR) {
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      continue;
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    } else if (errno == ETIMEDOUT) {
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      return false;
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    } else {
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      assert_with_errno(false, "timedwait failed");
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      return false;
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    }
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  }
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}
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#endif // __APPLE__
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