[2/9] mesos git commit: Move synchronized.hpp into stout.

[be...@apache.org]

Move synchronized.hpp into stout.

Review: https://reviews.apache.org/r/35012


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/90c10cbd
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/90c10cbd
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/90c10cbd

Branch: refs/heads/master
Commit: 90c10cbd6ff183b2ed00cfd98451ea5b9abd9f5b
Parents: 9f9d773
Author: Joris Van Remoortere <jo...@gmail.com>
Authored: Thu Jun 4 00:24:45 2015 -0700
Committer: Benjamin Hindman <be...@gmail.com>
Committed: Thu Jun 4 00:24:45 2015 -0700

----------------------------------------------------------------------
 .../3rdparty/stout/include/Makefile.am          |  1 +
 .../stout/include/stout/synchronized.hpp        | 75 ++++++++++++++++++++
 2 files changed, 76 insertions(+)
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http://git-wip-us.apache.org/repos/asf/mesos/blob/90c10cbd/3rdparty/libprocess/3rdparty/stout/include/Makefile.am
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diff --git a/3rdparty/libprocess/3rdparty/stout/include/Makefile.am b/3rdparty/libprocess/3rdparty/stout/include/Makefile.am
index 79239d7..6ac2f04 100644
--- a/3rdparty/libprocess/3rdparty/stout/include/Makefile.am
+++ b/3rdparty/libprocess/3rdparty/stout/include/Makefile.am
@@ -72,6 +72,7 @@ nobase_include_HEADERS =		\
   stout/strings.hpp			\
   stout/subcommand.hpp			\
   stout/svn.hpp				\
+  stout/synchronized.hpp		\
   stout/tests/utils.hpp			\
   stout/thread.hpp			\
   stout/try.hpp				\

http://git-wip-us.apache.org/repos/asf/mesos/blob/90c10cbd/3rdparty/libprocess/3rdparty/stout/include/stout/synchronized.hpp
----------------------------------------------------------------------
diff --git a/3rdparty/libprocess/3rdparty/stout/include/stout/synchronized.hpp b/3rdparty/libprocess/3rdparty/stout/include/stout/synchronized.hpp
new file mode 100644
index 0000000..60eaf26
--- /dev/null
+++ b/3rdparty/libprocess/3rdparty/stout/include/stout/synchronized.hpp
@@ -0,0 +1,75 @@
+/**
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __STOUT_SYNCHRONIZED_HPP__
+#define __STOUT_SYNCHRONIZED_HPP__
+
+#include <atomic>
+#include <mutex>
+#include <type_traits>
+
+// A helper class for the synchronized(m) macro. It is an RAII 'guard'
+// for a synchronization primitive 'T'. The general template handles
+// cases such as 'std::mutex' and 'std::recursive_mutex'.
+template <typename T>
+class Synchronized
+{
+public:
+  Synchronized(T* _lock) : lock(CHECK_NOTNULL(_lock)) { lock->lock(); }
+  Synchronized(T** _lock) : Synchronized(*CHECK_NOTNULL(_lock)) {}
+
+  ~Synchronized() { lock->unlock(); }
+
+  operator bool() const { return true; }
+private:
+  T* lock;
+};
+
+
+// A specialization of the Synchronized class for 'std::atomic_flag'.
+// This is necessary as the locking functions are different.
+template <>
+class Synchronized<std::atomic_flag>
+{
+public:
+  Synchronized(std::atomic_flag* _flag) : flag(CHECK_NOTNULL(_flag))
+  {
+    while (flag->test_and_set(std::memory_order_acquire)) {}
+  }
+  Synchronized(std::atomic_flag** _flag)
+    : Synchronized(*CHECK_NOTNULL(_flag)) {}
+
+  ~Synchronized()
+  {
+    flag->clear(std::memory_order_release);
+  }
+
+  operator bool() const { return true; }
+private:
+  std::atomic_flag* flag;
+};
+
+
+// A macro for acquiring a scoped 'guard' on any type that can satisfy
+// the 'Synchronized' interface. Currently this includes 'std::mutex',
+// 'std::recursive_mutex' and 'std::atomic_flag'.
+// Example:
+//   std::mutex m;
+//   synchronized (m) {
+//     // Do something under the lock.
+//   }
+#define synchronized(m)                                                 \
+  if (auto __ ## __file__ ## _ ## __line__ ## __lock = Synchronized<typename std::remove_pointer<decltype(m)>::type>(&m)) // NOLINT(whitespace/line_length)
+
+#endif // __STOUT_SYNCHRONIZED_HPP__