SERVER-41358 Created condition_variable polyfill

4 files changed, 209 insertions, 0 deletions

diff --git a/src/mongo/platform/SConscript b/src/mongo/platform/SConscript
index 6ccbf7f77ce..2a6c8a4f0bc 100644
--- a/src/mongo/platform/SConscript
+++ b/src/mongo/platform/SConscript
@@ -8,6 +8,7 @@ env.CppUnitTest(
         'atomic_proxy_test.cpp',
         'atomic_word_test.cpp',
         'bits_test.cpp',
+        'condition_variable_test.cpp',
         'endian_test.cpp',
         'mutex_test.cpp',
         'process_id_test.cpp',
diff --git a/src/mongo/platform/condition_variable.cpp b/src/mongo/platform/condition_variable.cpp
new file mode 100644
index 00000000000..76de1ca6d2b
--- /dev/null
+++ b/src/mongo/platform/condition_variable.cpp
@@ -0,0 +1,44 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program 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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/platform/condition_variable.h"
+
+namespace mongo {
+void ConditionVariable::wait(lock_t& lock) {
+    _condvar.wait(lock);
+}
+
+void ConditionVariable::notify_one() noexcept {
+    _condvar.notify_one();
+}
+
+void ConditionVariable::notify_all() noexcept {
+    _condvar.notify_all();
+}
+}  // namespace mongo
diff --git a/src/mongo/platform/condition_variable.h b/src/mongo/platform/condition_variable.h
new file mode 100644
index 00000000000..5b5f2f3c79b
--- /dev/null
+++ b/src/mongo/platform/condition_variable.h
@@ -0,0 +1,103 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program 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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+#include "mongo/platform/basic.h"
+
+#include "mongo/platform/mutex.h"
+#include "mongo/stdx/condition_variable.h"
+#include "mongo/util/diagnostic_info.h"
+
+
+namespace mongo {
+class ConditionVariable : private stdx::condition_variable_any {
+    using lock_t = stdx::unique_lock<Mutex>;
+
+public:
+    void wait(lock_t& lock);
+
+    template <class Predicate>
+    void wait(lock_t& lock, Predicate pred);
+
+    template <class Rep, class Period>
+    stdx::cv_status wait_for(lock_t& lock, const stdx::chrono::duration<Rep, Period>& rel_time);
+
+    template <class Rep, class Period, class Predicate>
+    bool wait_for(lock_t& lock,
+                  const stdx::chrono::duration<Rep, Period>& rel_time,
+                  Predicate pred);
+
+    template <class Clock, class Duration>
+    stdx::cv_status wait_until(lock_t& lock,
+                               const stdx::chrono::time_point<Clock, Duration>& timeout_time);
+
+    template <class Clock, class Duration, class Predicate>
+    bool wait_until(lock_t& lock,
+                    const stdx::chrono::time_point<Clock, Duration>& timeout_time,
+                    Predicate pred);
+
+    void notify_one() noexcept;
+    void notify_all() noexcept;
+
+private:
+    stdx::condition_variable_any _condvar;
+};
+
+template <class Predicate>
+void ConditionVariable::wait(lock_t& lock, Predicate pred) {
+    _condvar.wait(lock, pred);
+}
+
+template <class Rep, class Period>
+stdx::cv_status ConditionVariable::wait_for(lock_t& lock,
+                                            const stdx::chrono::duration<Rep, Period>& rel_time) {
+    return _condvar.wait_for(lock, rel_time);
+}
+
+template <class Rep, class Period, class Predicate>
+bool ConditionVariable::wait_for(lock_t& lock,
+                                 const stdx::chrono::duration<Rep, Period>& rel_time,
+                                 Predicate pred) {
+    return _condvar.wait_for(lock, rel_time, pred);
+}
+
+template <class Clock, class Duration>
+stdx::cv_status ConditionVariable::wait_until(
+    lock_t& lock, const stdx::chrono::time_point<Clock, Duration>& timeout_time) {
+    return _condvar.wait_until(lock, timeout_time);
+}
+
+template <class Clock, class Duration, class Predicate>
+bool ConditionVariable::wait_until(lock_t& lock,
+                                   const stdx::chrono::time_point<Clock, Duration>& timeout_time,
+                                   Predicate pred) {
+    return _condvar.wait_until(lock, timeout_time, pred);
+}
+
+}  // namespace mongo
diff --git a/src/mongo/platform/condition_variable_test.cpp b/src/mongo/platform/condition_variable_test.cpp
new file mode 100644
index 00000000000..cd12e037537
--- /dev/null
+++ b/src/mongo/platform/condition_variable_test.cpp
@@ -0,0 +1,61 @@
+/**
+ *    Copyright (C) 2018-present MongoDB, Inc.
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the Server Side Public License, version 1,
+ *    as published by MongoDB, Inc.
+ *
+ *    This program 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
+ *    Server Side Public License for more details.
+ *
+ *    You should have received a copy of the Server Side Public License
+ *    along with this program. If not, see
+ *    <http://www.mongodb.com/licensing/server-side-public-license>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the Server Side Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#include "mongo/unittest/unittest.h"
+
+#include "mongo/platform/condition_variable.h"
+#include "mongo/platform/mutex.h"
+#include "mongo/stdx/thread.h"
+#include "mongo/unittest/barrier.h"
+
+namespace mongo {
+
+TEST(ConditionVariable, BasicSingleThread) {
+    unittest::Barrier barrier(2U);
+    ConditionVariable cv;
+    Mutex m;
+    bool done = false;
+
+    stdx::thread worker([&]() {
+        stdx::unique_lock<Mutex> lk(m);
+        barrier.countDownAndWait();
+        ASSERT(!done);
+        cv.wait(lk, [&] { return done; });
+        ASSERT(done);
+    });
+
+    barrier.countDownAndWait();
+    {
+        stdx::unique_lock<Mutex> lk(m);
+        done = true;
+    }
+    cv.notify_one();
+    worker.join();
+}
+}