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diff --git a/src/components/include/utils/conditional_variable.h b/src/components/include/utils/conditional_variable.h
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+/**
+ * Copyright (c) 2013, Ford Motor Company
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright 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 the Ford Motor Company 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 HOLDER 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, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+#ifndef SRC_COMPONENTS_INCLUDE_UTILS_CONDITIONAL_VARIABLE_H_
+#define SRC_COMPONENTS_INCLUDE_UTILS_CONDITIONAL_VARIABLE_H_
+
+#if defined(OS_POSIX)
+#include <pthread.h>
+#else
+#error Please implement conditional variable for your OS
+#endif
+#include <stdint.h>
+
+#include "utils/macro.h"
+
+namespace sync_primitives {
+class AutoLock;
+
+namespace impl {
+#if defined(OS_POSIX)
+typedef pthread_cond_t PlatformConditionalVariable;
+#endif
+}  // namespace impl
+
+/*
+ * Conditional variable wrapper
+ * Conditional variable is a thing that can be waited on
+ * Wait is finished when other thread puts that thing in a signaled state
+ * (or when timeout is over).
+ * Data that is conditionally accessed should be protected by
+ * a Lock and that lock must be taken before starting to Wait.
+ * When wait is performed, Lock is temporarly released.
+ * When wait is finished, Lock is captured back.
+ * WARNING: Beware of Spurious wakeups
+ * http://en.wikipedia.org/wiki/Spurious_wakeup
+ * Thread can wake up from wait spuriously, without conditional
+ * variable being actually set by other thread. This means
+ * additional check should be made right after thread awakening
+ * and if check fails thread should continue waiting.
+ *
+ * while(!DataReady()) cond_var.Wait(auto_lock);
+ *
+ */
+class ConditionalVariable {
+ public:
+  enum WaitStatus { kNoTimeout, kTimeout };
+  ConditionalVariable();
+  ~ConditionalVariable();
+  // Wakes up single thread that is waiting on this conditional variable
+  void NotifyOne();
+  // Wakes up all waiting threads
+  void Broadcast();
+
+  // Wait forever or up to milliseconds time limit
+  void Wait(AutoLock& auto_lock);
+  WaitStatus WaitFor(AutoLock& auto_lock, int32_t milliseconds);
+ private:
+  impl::PlatformConditionalVariable cond_var_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ConditionalVariable);
+};
+
+}  // namespace sync_primitives
+#endif  // SRC_COMPONENTS_INCLUDE_UTILS_CONDITIONAL_VARIABLE_H_