--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/os/bsd/semaphore_bsd.cpp	Thu Jan 11 18:42:36 2018 -0500
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled/precompiled.hpp"
+#include "semaphore_bsd.hpp"
+#include "utilities/debug.hpp"
+
+#include <semaphore.h>
+
+#ifdef __APPLE__
+// OS X doesn't support unamed POSIX semaphores, so the implementation in os_posix.cpp can't be used.
+
+static const char* sem_init_strerror(kern_return_t value) {
+  switch (value) {
+    case KERN_INVALID_ARGUMENT:  return "Invalid argument";
+    case KERN_RESOURCE_SHORTAGE: return "Resource shortage";
+    default:                     return "Unknown";
+  }
+}
+
+OSXSemaphore::OSXSemaphore(uint value) {
+  kern_return_t ret = semaphore_create(mach_task_self(), &_semaphore, SYNC_POLICY_FIFO, value);
+
+  guarantee(ret == KERN_SUCCESS, "Failed to create semaphore: %s", sem_init_strerror(ret));
+}
+
+OSXSemaphore::~OSXSemaphore() {
+  semaphore_destroy(mach_task_self(), _semaphore);
+}
+
+void OSXSemaphore::signal(uint count) {
+  for (uint i = 0; i < count; i++) {
+    kern_return_t ret = semaphore_signal(_semaphore);
+
+    assert(ret == KERN_SUCCESS, "Failed to signal semaphore");
+  }
+}
+
+void OSXSemaphore::wait() {
+  kern_return_t ret;
+  while ((ret = semaphore_wait(_semaphore)) == KERN_ABORTED) {
+    // Semaphore was interrupted. Retry.
+  }
+  assert(ret == KERN_SUCCESS, "Failed to wait on semaphore");
+}
+
+int64_t OSXSemaphore::currenttime() {
+  struct timeval tv;
+  gettimeofday(&tv, NULL);
+  return (tv.tv_sec * NANOSECS_PER_SEC) + (tv.tv_usec * 1000);
+}
+
+bool OSXSemaphore::trywait() {
+  return timedwait(0, 0);
+}
+
+bool OSXSemaphore::timedwait(unsigned int sec, int nsec) {
+  kern_return_t kr = KERN_ABORTED;
+  mach_timespec_t waitspec;
+  waitspec.tv_sec = sec;
+  waitspec.tv_nsec = nsec;
+
+  int64_t starttime = currenttime();
+
+  kr = semaphore_timedwait(_semaphore, waitspec);
+  while (kr == KERN_ABORTED) {
+    int64_t totalwait = (sec * NANOSECS_PER_SEC) + nsec;
+
+    int64_t current = currenttime();
+    int64_t passedtime = current - starttime;
+
+    if (passedtime >= totalwait) {
+      waitspec.tv_sec = 0;
+      waitspec.tv_nsec = 0;
+    } else {
+      int64_t waittime = totalwait - (current - starttime);
+      waitspec.tv_sec = waittime / NANOSECS_PER_SEC;
+      waitspec.tv_nsec = waittime % NANOSECS_PER_SEC;
+    }
+
+    kr = semaphore_timedwait(_semaphore, waitspec);
+  }
+
+  return kr == KERN_SUCCESS;
+}
+#endif // __APPLE__