progminer zano miner fork https://github.com/hyle-team/progminer

zano/libdevcore/Guards.h

@@ -0,0 +1,76 @@
+/*
+    This file is part of progminer.
+
+    progminer is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    progminer 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 for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with progminer.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/** @file Guards.h
+ * @author Gav Wood <i@gavwood.com>
+ * @date 2014
+ */
+
+#pragma once
+
+#include <atomic>
+#include <mutex>
+
+namespace dev
+{
+using Mutex = std::mutex;
+using Guard = std::lock_guard<std::mutex>;
+using UniqueGuard = std::unique_lock<std::mutex>;
+
+template <class GuardType, class MutexType>
+struct GenericGuardBool : GuardType
+{
+    GenericGuardBool(MutexType& _m) : GuardType(_m) {}
+    bool b = true;
+};
+
+/** @brief Simple block guard.
+ * The expression/block following is guarded though the given mutex.
+ * Usage:
+ * @code
+ * Mutex m;
+ * unsigned d;
+ * ...
+ * ETH_(m) d = 1;
+ * ...
+ * ETH_(m) { for (auto d = 10; d > 0; --d) foo(d); d = 0; }
+ * @endcode
+ *
+ * There are several variants of this basic mechanism for different Mutex types and Guards.
+ *
+ * There is also the UNGUARD variant which allows an unguarded expression/block to exist within a
+ * guarded expression. eg:
+ *
+ * @code
+ * Mutex m;
+ * int d;
+ * ...
+ * ETH_GUARDED(m)
+ * {
+ *   for (auto d = 50; d > 25; --d)
+ *     foo(d);
+ *   ETH_UNGUARDED(m)
+ *     bar();
+ *   for (; d > 0; --d)
+ *     foo(d);
+ * }
+ * @endcode
+ */
+
+#define DEV_GUARDED(MUTEX) \
+    for (GenericGuardBool<Guard, Mutex> __eth_l(MUTEX); __eth_l.b; __eth_l.b = false)
+
+}  // namespace dev