printf(\ //提取每个线程的信息到相应数据结构中; while(inFile){ inFile >> Thread_Info[n_Thread].serial; inFile >> Thread_Info[n_Thread].entity; inFile >> Thread_Info[n_Thread].delay; char c; inFile.get(c); while(c!='\\n'&& !inFile.eof()){ inFile>>
Thread_Info[n_Thread].thread_request[Thread_Info[n_Thread].n_request++]; inFile.get(c); } n_Thread++; } //回显获得的线程信息,便于确认正确性; for(j=0;j<(int) n_Thread;j++){ int Temp_serial = Thread_Info[j].serial; char Temp_entity = Thread_Info[j].entity; double Temp_delay = Thread_Info[j].delay; printf(\\\n thread- %c %f \,Temp_delay); int Temp_request = Thread_Info[j].n_request; for(int k=0;k //创建在模拟过程中几个必要的信号量 empty_semaphore=CreateSemaphore(NULL,n_Buffer_or_Critical,n_Buffer_or_Critical, \ h_mutex= CreateMutex(NULL,FALSE,\ //下面这个循环用线程的ID号来为相应生产线程的产品读写时所 //使用的同步信号量命名; for(j=0;j<(int)n_Thread;j++){ std::string lp =\ int temp =j; while(temp){ char c = (char)(temp); lp+=c; 36 temp/=10; } h_Semaphore[j+1]=CreateSemaphore(NULL,0,n_Thread,lp.c_str()); } //创建生产者和消费者线程; for(i =0;i< (int) n_Thread;i++){ if(Thread_Info[i].entity =='P') h_Thread[i]= CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(Produce), &(Thread_Info[i]),0,NULL); else h_Thread[i]=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(Consume), &(Thread_Info[i]),0,NULL); } //主程序等待各个线程的动作结束; wait_for_all = WaitForMultipleObjects(n_Thread,h_Thread,TRUE,-1); printf(\ printf(\ _getch(); return 0; } //确认是否还有对同一产品的消费请求未执行; bool IfInOtherRequest(int req) { for(int i=0;i //找出当前可以进行产品生产的空缓冲区位置; int FindProducePosition() { int EmptyPosition; for (int i =0;i 37 //用下面这个特殊值表示本缓冲区正处于被写状态; Buffer_Critical[i] = -2; break; } return EmptyPosition; } //找出当前所需生产者生产的产品的位置; int FindBufferPosition(int ProPos) { int TempPos; for (int i =0 ;i //生产者进程 void Produce(void *p) { //局部变量声明; DWORD wait_for_semaphore,wait_for_mutex,m_delay; int m_serial; //获得本线程的信息; m_serial = ((ThreadInfo*)(p))->serial; m_delay = (DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC); Sleep(m_delay); //开始请求生产 printf(\ //确认有空缓冲区可供生产,同时将空位置数empty减1;用于生产者和消费者的同步; wait_for_semaphore = WaitForSingleObject(empty_semaphore,-1); //互斥访问下一个可用于生产的空临界区,实现写写互斥; wait_for_mutex = WaitForSingleObject(h_mutex,-1); int ProducePos = FindProducePosition(); ReleaseMutex(h_mutex); //生产者在获得自己的空位置并做上标记后,以下的写操作在生产者之间可 38 以并发; //核心生产步骤中,程序将生产者的ID作为产品编号放入,方便消费者识别; printf(\- begin to produce at position -.\\n\ Buffer_Critical[ProducePos] = m_serial; printf(\ printf(\ position[ - ]:= \\n\ //使生产者写的缓冲区可以被多个消费者使用,实现读写同步; ReleaseSemaphore(h_Semaphore[m_serial],n_Thread,NULL); } //消费者进程 void Consume(void * p) { //局部变量声明; DWORD wait_for_semaphore,m_delay; int m_serial,m_requestNum; //消费者的序列号和请求的数目; int m_thread_request[MAX_THREAD_NUM];//本消费线程的请求队列; //提取本线程的信息到本地; m_serial = ((ThreadInfo*)(p))->serial; m_delay = (DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC); m_requestNum = ((ThreadInfo *)(p))->n_request; for (int i = 0;i wait_for_semaphore=WaitForSingleObject(h_Semaphore[m_thread_request[i]],-1); //查询所需产品放到缓冲区的号 int BufferPos=FindBufferPosition(m_thread_request[i]); //开始进行具体缓冲区的消费处理,读和读在该缓冲区上仍然是互斥的; //进入临界区后执行消费动作;并在完成此次请求后,通知另外的消费者 39 本处请求已 //经满足;同时如果对应的产品使用完毕,就做相应处理;并给出相应动作的界面提 //示;该相应处理指将相应缓冲区清空,并增加代表空缓冲区的信号量; EnterCriticalSection(&PC_Critical[BufferPos]); printf(\begin to consume - product \\n\ ((ThreadInfo*)(p))->thread_request[i] =-1; if(!IfInOtherRequest(m_thread_request[i])){ Buffer_Critical[BufferPos] = -1;//标记缓冲区为空; printf(\finish consuming -:\\n \ printf(\ position[ - ]:= \\n\ ReleaseSemaphore(empty_semaphore,1,NULL); } else{ printf(\- finish consuming product -\\n \ } //离开临界区 LeaveCriticalSection(&PC_Critical[BufferPos]); } } 1. 操作能否正常执行,如不能,有 什么错误,如何修改的? 该程序运行后没有错误 2. 你输入的test.txt文件中的数据是: 3 1 p 3 2 P 4 3 C 4 1 4 P 2 5 C 3 1 2 4 3. 运行结果是: 40 4.运行结果中第三行代表的是什么含义: 生产者生产的过程已结束,生产的产品已生成。 41