一．ReaderAndWriter.CPP文件的具体内容： // 来自:windows 内核实验教程 // 机械工业出版社 // ISBN:7-111-10880-9/TP.2600 //制作者:yuhejun@126.com // For more information:www.surstar.com // 2005.11.9 // beijing changping // Debug Vision // Description:这是一个关于操作系统内核实验的一段程序,读者和写者的问题的模拟实现. // 开发环境:WINXP +VC6  Console Application     #include "windows.h" #include <conio.h> #include <stdlib.h> #include <fstream.h> #include <io.h> #include <string.h> #include <stdio.h>   #define READER 'R'                   //读者 #define WRITER 'W'                   //写者 #define INTE_PER_SEC 1000            //每秒时钟中断的数目 #define MAX_THREAD_NUM 64            //最大线程数 #define MAX_FILE_NUM 32              //最大文件数目数 #define MAX_STR_LEN 32               //字符串的长度   int readcount=0;                     //读者数目 int writecount=0;                    //写者数目 CRITICAL_SECTION RP_Write;           //临界资源 CRITICAL_SECTION cs_Write; CRITICAL_SECTION cs_Read; struct ThreadInfo {        int serial;                      //线程序号        char entity;                     //线程类别(判断是读者还是写者线程)        double delay;                    //线程延迟时间        double persist;                  //线程读写操作时间 };     /////////////////////////////////////////////////////////////////////////// // 读者优先---读者线程 //P:读者线程信息       void RP_ReaderThread(void *p) {          //互斥变量        HANDLE h_Mutex;        h_Mutex=OpenMutex(MUTEX_ALL_ACCESS,FALSE,"mutex_for_readcount");                      DWORD wait_for_mutex;            //等待互斥变量所有权        DWORD m_delay;                   //延迟时间        DWORD m_persist;                 //读文件持续时间        int m_serial;                    //线程序号        //  从参数中获得信息        m_serial=((ThreadInfo*)(p))->serial ;        m_delay=(DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC);        m_persist=(DWORD)(((ThreadInfo*)(p))->persist *INTE_PER_SEC);        Sleep(m_delay);                  //延迟等待            printf("Reader thread %d sents the reading require.\n",m_serial);                   //等待互斥信号,保证对ReadCount 的访问,修改互斥        wait_for_mutex=WaitForSingleObject(h_Mutex,-1);        //读者数目增加        readcount++;        if(readcount==1)        {               //第一个读者,等待资源               EnterCriticalSection(&RP_Write);        }        ReleaseMutex(h_Mutex);            //释放互斥信号              //读文件        printf("Reader thread %d begins to read file.\n",m_serial); Sleep(m_persist);          //退出线程        printf("Reader thread %d finished reading file.\n",m_serial);        //等待互斥信号,保证对ReadCount的访问,修改互斥        wait_for_mutex=WaitForSingleObject(h_Mutex,-1);        //读者数目减少         readcount--;         if(readcount==0)         {                //如果所有的读者读完,唤醒写者                LeaveCriticalSection(&RP_Write);         }         ReleaseMutex(h_Mutex);          //释放互斥信号 }     ////////////////////////////////////////////////////////////// //P:写者线程信息     void RP_WriterThread(void *p) {        DWORD m_delay;                   //延迟时间        DWORD m_persist;                 //写文件持续时间        int m_serial;                    //线程序号        //  从参数中获得信息        m_serial=((ThreadInfo*)(p))->serial ;        m_delay=(DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC);        m_persist=(DWORD)(((ThreadInfo*)(p))->persist *INTE_PER_SEC);        Sleep(m_delay);               printf("Write thread %d sents the writing require.\n",m_serial);            //等待资源        EnterCriticalSection(&RP_Write);          //写文件        printf("Writer thread %d begins to write to the file.\n",m_serial);        Sleep(m_persist);            //退出线程 printf("Write thread %d finished writing to the file.\n",m_serial);        //释放资源        LeaveCriticalSection(&RP_Write); }     ////////////////////////////////////////////////////////////// //读者优先处理函数 //file:文件名     void ReaderPriority(char *file) {        DWORD n_thread=0;           //线程数目        DWORD thread_ID;            //线程ID        DWORD wait_for_all;         //等待所有线程结束                //互斥对象        HANDLE h_Mutex;        h_Mutex=CreateMutex(NULL,FALSE,"mutex_for_readcount");            //线程对象的数组        HANDLE h_Thread[MAX_THREAD_NUM];        ThreadInfo thread_info[MAX_THREAD_NUM];          readcount=0;               //初始化readcount        InitializeCriticalSection(&RP_Write);        //初始化临界区        ifstream inFile;        inFile.open (file);        printf("Reader Priority:\n\n");        while(inFile)        {               //读入每一个读者,写者的信息               inFile>>thread_info[n_thread].serial;               inFile>>thread_info[n_thread].entity;               inFile>>thread_info[n_thread].delay;               inFile>>thread_info[n_thread++].persist;               inFile.get();        }        for(int i=0;i<(int)(n_thread);i++) {               if(thread_info[i].entity==READER||thread_info[i].entity =='r')               {                      //创建读者进程                      h_Thread[i]=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(RP_ReaderThread),&thread_info[i],0,&thread_ID);               }               else               {                      //创建写线程                      h_Thread[i]=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)(RP_WriterThread),&thread_info[i],0,&thread_ID);               }          }        //等待所有的线程结束        wait_for_all=WaitForMultipleObjects(n_thread,h_Thread,TRUE,-1);        printf("All reader and writer have finished operating.\n"); }   //////////////////////////////////////////////////////// //写者优先---读者线程 //P:读者线程信息     void WP_ReaderThread(void *p) {          //互斥变量        HANDLE h_Mutex1;        h_Mutex1=OpenMutex(MUTEX_ALL_ACCESS,FALSE,"mutex1");        HANDLE h_Mutex2;     h_Mutex2=OpenMutex(MUTEX_ALL_ACCESS,FALSE,"mutex2");            DWORD wait_for_mutex1;            //等待互斥变量所有权        DWORD wait_for_mutex2;        DWORD m_delay;                     //延迟时间        DWORD m_persist;                   //读文件持续时间        int m_serial;                      //线程的序号        //从参数中得到信息        m_serial=((ThreadInfo*)(p))->serial ;        m_delay=(DWORD)(((ThreadInfo*)(p))->delay *INTE_PER_SEC);        m_persist=(DWORD)(((ThreadInfo*)(p))->persist *INTE_PER_SEC);        Sleep(m_delay);                  //延迟等待            printf("Reader thread %d sents the reading require.\n",m_serial);        wait_for_mutex1=WaitForSingleObject(h_Mutex1,-1);          //读者进去临界区        EnterCriticalSection(&cs_Read);          //阻塞互斥对象Mutex2,保证对readCount的访问和修改互斥         wait_for_mutex2=WaitForSingleObject(h_Mutex2,-1);         //修改读者的数目         readcount++;         if(readcount==1)         {                // 如果是第1个读者,等待写者写完                EnterCriticalSection(&cs_Write);         }         ReleaseMutex(h_Mutex2);// 释放互斥信号 Mutex2         //让其他读者进去临界区         LeaveCriticalSection(&cs_Read);         ReleaseMutex(h_Mutex1);         //读文件         printf("Reader thread %d begins to read file.\n",m_serial);         Sleep(m_persist);             //退出线程    printf("Reader thread %d finished reading  file.\n",m_serial);    //阻塞互斥对象Mutex2,保证对readcount的访问,修改互斥    wait_for_mutex2=WaitForSingleObject(h_Mutex2,-1);    readcount--;    if(readcount==0)    {           //最后一个读者,唤醒写者           LeaveCriticalSection(&cs_Write);    }    ReleaseMutex(h_Mutex2);  //释放互斥信号 }    

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