be/src/gutil/spinlock_posix-inl.h

// -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*-
/* Copyright (c) 2009, Google Inc.
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 * modification, are permitted provided that the following conditions are
 * met:
 * 
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 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * ---
 * This file is a Posix-specific part of spinlock_internal.cc
 */

#include <errno.h>
#if defined(HAVE_SCHED_H) || defined(__APPLE__)
#include <sched.h>      /* For sched_yield() */
#endif
#include <time.h>       /* For nanosleep() */

namespace base {
namespace internal {

void SpinLockDelay(volatile Atomic32 *w, int32 value, int loop) {
  int save_errno = errno;
  if (loop == 0) {
  } else if (loop == 1) {
    sched_yield();
  } else {
    struct timespec tm;
    tm.tv_sec = 0;
    tm.tv_nsec = base::internal::SuggestedDelayNS(loop);
    nanosleep(&tm, NULL);
  }
  errno = save_errno;
}

void SpinLockWake(volatile Atomic32 *w, bool all) {
}

} // namespace internal
} // namespace base