[2392] | 1 | // |
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| 2 | // C++ Interface: concurrent |
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| 3 | // |
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| 4 | // Description: |
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| 5 | // |
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| 6 | // |
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| 7 | // Author: Kohji Nakamura <k.nakamura@nao.ac.jp>, (C) 2012 |
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| 8 | // |
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| 9 | // Copyright: See COPYING file that comes with this distribution |
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| 10 | // |
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| 11 | // |
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| 12 | #ifndef CONCURRENT_H |
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| 13 | #define CONCURRENT_H |
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| 14 | |
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| 15 | #include <assert.h> |
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| 16 | #include <pthread.h> |
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| 17 | |
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| 18 | namespace concurrent { |
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| 19 | class PCException { |
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| 20 | public: |
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| 21 | virtual void raise() /*throw(PCException)*/ { throw *this; } |
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| 22 | virtual ~PCException() {} |
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| 23 | }; |
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| 24 | |
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| 25 | //typedef void (*produce_t)(void *context) throw(PCException); |
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| 26 | //typedef void (*consume_t)(void *context) throw(PCException); |
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| 27 | |
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| 28 | class Mutex { |
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| 29 | pthread_mutex_t mutex; |
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| 30 | public: |
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| 31 | Mutex() throw(int); |
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| 32 | virtual ~Mutex(); |
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| 33 | void lock() throw(int); |
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| 34 | /** |
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[2395] | 35 | * Returns true if this thread could lock. |
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[2392] | 36 | * Returns false if already locked. |
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| 37 | */ |
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| 38 | bool try_lock() throw(int); |
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| 39 | void unlock() throw(int); |
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| 40 | private: |
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| 41 | Mutex(Mutex const &other); |
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| 42 | Mutex &operator =(Mutex const &other); |
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| 43 | }; |
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| 44 | |
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| 45 | class Semaphore { |
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| 46 | pthread_mutex_t mutex; |
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| 47 | pthread_cond_t cond; |
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| 48 | unsigned sem; |
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| 49 | public: |
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| 50 | explicit Semaphore(unsigned initial = 0U) throw(int); |
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| 51 | void up(unsigned amount = 1U) throw(int); |
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| 52 | void down(unsigned amount = 1U) throw(int); |
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| 53 | virtual ~Semaphore(); |
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| 54 | private: |
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| 55 | Semaphore(Semaphore const &other); |
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| 56 | Semaphore &operator =(Semaphore const &other); |
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| 57 | }; |
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| 58 | |
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| 59 | class FIFOException { |
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| 60 | public: |
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| 61 | virtual void raise() { throw *this; } |
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| 62 | virtual ~FIFOException() {} |
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| 63 | }; |
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| 64 | |
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| 65 | class EmptyException { |
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| 66 | public: |
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| 67 | virtual void raise() { throw *this; } |
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| 68 | virtual ~EmptyException() {} |
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| 69 | }; |
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| 70 | |
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| 71 | class FullException { |
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| 72 | public: |
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| 73 | virtual void raise() { throw *this; } |
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| 74 | virtual ~FullException() {} |
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| 75 | }; |
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| 76 | |
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| 77 | template <class T, size_t N> |
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| 78 | class FIFO { |
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| 79 | T elements[N + 1]; // +1 to make an implementation simple. |
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| 80 | Mutex mutex; |
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| 81 | size_t head; |
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| 82 | size_t tail; |
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| 83 | |
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| 84 | size_t wrap(size_t n) { |
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| 85 | return n % (N + 1); |
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| 86 | } |
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| 87 | |
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| 88 | void reset() { |
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| 89 | head = tail = 0; |
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| 90 | } |
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| 91 | |
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| 92 | public: |
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| 93 | FIFO() { |
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| 94 | assert(N > 0); |
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| 95 | reset(); |
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| 96 | } |
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| 97 | virtual ~FIFO() { |
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| 98 | mutex.lock(); // wait until current lock is released. |
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| 99 | mutex.unlock(); |
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| 100 | } |
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| 101 | |
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| 102 | virtual void lock() { |
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| 103 | mutex.lock(); |
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| 104 | } |
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| 105 | |
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| 106 | /** |
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[2395] | 107 | * Returns true if this thread could lock. |
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[2392] | 108 | * Returns false if already locked. |
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| 109 | */ |
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| 110 | virtual bool try_lock() { |
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| 111 | return mutex.try_lock(); |
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| 112 | } |
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| 113 | |
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| 114 | virtual void unlock() { |
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| 115 | mutex.unlock(); |
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| 116 | } |
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| 117 | |
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| 118 | virtual void clear() { |
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| 119 | reset(); |
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| 120 | } |
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| 121 | |
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| 122 | virtual void put(T const &value) throw(FullException) { |
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| 123 | size_t new_tail = wrap(tail + 1); |
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| 124 | if (head == new_tail) { |
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| 125 | throw FullException(); |
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| 126 | } |
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| 127 | elements[tail] = value; |
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| 128 | tail = new_tail; |
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| 129 | } |
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| 130 | |
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| 131 | virtual T get() throw(EmptyException) { |
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| 132 | if (head == tail) { |
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| 133 | throw EmptyException(); |
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| 134 | } |
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| 135 | T result = elements[head]; |
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| 136 | head = wrap(head + 1); |
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| 137 | return result; |
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| 138 | } |
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| 139 | |
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| 140 | /** |
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| 141 | * Returns capacity size. |
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| 142 | */ |
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| 143 | virtual size_t size() const { |
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| 144 | return N; |
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| 145 | } |
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| 146 | |
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| 147 | /** |
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| 148 | * Returns number of elements in this FIFO. |
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| 149 | */ |
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| 150 | virtual size_t length() const { |
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| 151 | size_t result = tail - head; |
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| 152 | if (head > tail) { |
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| 153 | result = N + 1 - (head - tail); |
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| 154 | } |
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| 155 | return result; |
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| 156 | } |
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| 157 | private: |
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| 158 | FIFO(FIFO const &other); |
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| 159 | FIFO &operator =(FIFO const &other); |
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| 160 | }; |
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| 161 | |
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| 162 | class Broker { |
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| 163 | protected: |
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| 164 | enum ThreadSpec { |
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| 165 | ProdAsMaster, ConsAsMaster, Unspecified |
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| 166 | }; |
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| 167 | bool (*producer)(void *context) throw(PCException); |
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| 168 | void (*consumer)(void *context) throw(PCException); |
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| 169 | virtual void _run(void *context, unsigned do_ahead, ThreadSpec threadSpec) throw(PCException); |
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| 170 | public: |
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| 171 | Broker(bool (*producer)(void *context) throw(PCException), |
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| 172 | void (*consumer)(void *context) throw(PCException)); |
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| 173 | virtual ~Broker(); |
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| 174 | static void enableNested(); |
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| 175 | static void disableNested(); |
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| 176 | static void setNestedState(bool nested); |
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| 177 | static bool getNestedState(); |
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| 178 | |
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| 179 | virtual void run(void *context, unsigned do_ahead=1) throw(PCException); |
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| 180 | virtual void runProducerAsMasterThread(void *context, unsigned do_ahead=1) throw(PCException); |
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| 181 | virtual void runConsumerAsMasterThread(void *context, unsigned do_ahead=1) throw(PCException); |
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| 182 | virtual void runSequential(void *context) throw(PCException); |
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| 183 | }; |
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| 184 | |
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| 185 | #if 0 |
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| 186 | template <class Context, class Product> |
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| 187 | class Producer { |
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| 188 | public: |
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| 189 | virtual Product produce(Context &ctx) throw(PCException) = 0; |
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| 190 | virtual ~Producer() {} |
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| 191 | }; |
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| 192 | |
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| 193 | template <class Context, class Product> |
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| 194 | class Consumer { |
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| 195 | public: |
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| 196 | virtual void consume(Context &ctx, Product const&product) throw(PCException) = 0; |
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| 197 | virtual ~Consumer() {} |
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| 198 | }; |
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| 199 | |
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| 200 | class ProdCons { |
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| 201 | public: |
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| 202 | virtual ~ProdCons() {} |
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| 203 | |
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| 204 | virtual void runProducerAsMasterThread(void *context) throw(PCException) = 0; |
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| 205 | virtual void runConsumerAsMasterThread(void *context) throw(PCException) = 0; |
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| 206 | virtual void produce(void *context) throw(PCException) = 0; |
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| 207 | virtual void consume(void *context) throw(PCException) = 0; |
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| 208 | |
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| 209 | /** |
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| 210 | * <src>produce()</src> should call this method to |
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| 211 | * let consumer to know it is ready. |
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| 212 | */ |
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| 213 | virtual void ready() = 0; |
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| 214 | |
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| 215 | /** |
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| 216 | * Returns true if ready, |
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| 217 | * otherwise, finished or there was an error, returns false. |
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| 218 | * |
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| 219 | * <src>consume()</src> should call this method |
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| 220 | * to check if it is ready or not. |
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| 221 | * If false is returned, <src>isError()</src> or/and |
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| 222 | * <src>isFinished()</src> should be called to see the reason. |
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| 223 | */ |
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| 224 | virtual bool waitForReady() = 0; |
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| 225 | |
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| 226 | /** |
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| 227 | * Returns true if <src>produce()</src> was finished, |
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| 228 | * otherwise returns false. |
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| 229 | */ |
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| 230 | virtual bool isFinished() = 0; |
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| 231 | |
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| 232 | /** |
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| 233 | * <src>produce()</src>/<src>consume()</src> should call this method |
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| 234 | * to report error to <src>consume()</src>/<src>produce()</src>. |
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| 235 | */ |
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| 236 | virtual void reportError(void *errorInfo) = 0; |
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| 237 | |
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| 238 | /** |
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| 239 | * Returns true and set errorInfo if <src>reportError()</src> is called, |
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| 240 | * otherwise returns false and set errorInfo to NULL. |
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| 241 | */ |
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| 242 | virtual bool isError(void &*errorInfo) = 0; |
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| 243 | }; |
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| 244 | #endif |
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| 245 | |
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| 246 | } |
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| 247 | |
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| 248 | |
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| 249 | #endif |
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