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Diffstat (limited to 'qpid/cpp/src/qpid/sys/StateMonitor.h')
-rw-r--r-- | qpid/cpp/src/qpid/sys/StateMonitor.h | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/qpid/cpp/src/qpid/sys/StateMonitor.h b/qpid/cpp/src/qpid/sys/StateMonitor.h new file mode 100644 index 0000000000..eac37a8543 --- /dev/null +++ b/qpid/cpp/src/qpid/sys/StateMonitor.h @@ -0,0 +1,78 @@ +#ifndef QPID_SYS_STATEMONITOR_H +#define QPID_SYS_STATEMONITOR_H + +/* + * + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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. + * + */ +#include "qpid/sys/Waitable.h" + +#include <bitset> + +namespace qpid { +namespace sys { + +/** + * A monitor with an enum state value. + * + *@param Enum: enum type to use for states. + *@param EnumMax: Highest enum value. + */ +template <class Enum, size_t MaxEnum> +class StateMonitor : public Waitable +{ + public: + struct Set : public std::bitset<MaxEnum + 1> { + Set() {} + Set(Enum s) { set(s); } + Set(Enum s, Enum t) { std::bitset<MaxEnum + 1>::set(s).set(t); } + Set(Enum s, Enum t, Enum u) { std::bitset<MaxEnum + 1>::set(s).set(t).set(u); } + Set(Enum s, Enum t, Enum u, Enum v) { std::bitset<MaxEnum + 1>::set(s).set(t).set(u).set(v); } + }; + + + StateMonitor(Enum initial) { state=initial; } + + /** @pre Caller holds a ScopedLock. */ + void set(Enum s) { state=s; notifyAll(); } + /** @pre Caller holds a ScopedLock. */ + StateMonitor& operator=(Enum s) { set(s); return *this; } + + /** @pre Caller holds a ScopedLock. */ + Enum get() const { return state; } + /** @pre Caller holds a ScopedLock. */ + operator Enum() const { return state; } + + /** @pre Caller holds a ScopedLock */ + void waitFor(Enum s) { ScopedWait w(*this); while (s != state) wait(); } + /** @pre Caller holds a ScopedLock */ + void waitFor(Set s) { ScopedWait w(*this); while (!s.test(state)) wait(); } + /** @pre Caller holds a ScopedLock */ + void waitNot(Enum s) { ScopedWait w(*this); while (s == state) wait(); } + /** @pre Caller holds a ScopedLock */ + void waitNot(Set s) { ScopedWait w(*this); while (s.test(state)) wait(); } + + private: + Enum state; +}; + +}} + + +#endif /*!QPID_SYS_STATEMONITOR_H*/ |