消息緩沖通信進(jìn)程

1、消息緩沖通信進(jìn)程一、實(shí)習(xí)內(nèi)容消息緩沖通信過(guò)程（發(fā)送與接收）要求：（1）發(fā)送進(jìn)程A創(chuàng)建消息；（2）執(zhí)行send（B，a）后，查看進(jìn)程B的進(jìn)程控制塊（PCB）表 中mq，mutex， sm的情況，查看消息緩沖區(qū)中內(nèi)容。二、實(shí)習(xí)目的模擬實(shí)現(xiàn)進(jìn)程間通信過(guò)程，理解進(jìn)程通信的基本原理與所用數(shù)據(jù) 結(jié)構(gòu)，消息緩沖區(qū)、信號(hào)量及消息隊(duì)列的有關(guān)算法。三、實(shí)驗(yàn)數(shù)據(jù)結(jié)構(gòu)及符號(hào)說(shuō)明1、進(jìn)程控制塊（PCB）typedef struct PCBstring name;semaphore mutex;semaphore sm;message *mq;PCB（string n = ）name = n;mutex.value =

2、1;sm.value = 1;mq = NULL;PCB;2、消息緩沖區(qū)typedef struct messagestring sender;int size;string text;message *next;message()sender = size = -1;text = ；next = NULL;message;message *msg = new(message);message *back = msg;3、信號(hào)量typedef structint value;/PCB *list;semaphore;四、程序源代碼#include #include #include using

3、 namespace std;typedef struct messagestring sender;int size;string text;message *next;message()消息緩沖區(qū)聲明消息發(fā)送者消息長(zhǎng)度消息正文指向下一個(gè)消息緩沖區(qū)sender =size = -1;text = ；next = NULL;message;message *msg = new(message);/消息緩沖區(qū)message *back = msg;typedef struct/信號(hào)量int value;/PCB *list;semaphore;typedef struct PCBstring n

4、ame;semaphore mutex;semaphore sm;message *mq;PCB(string n = )進(jìn)程控制塊/進(jìn)程名互斥信號(hào)量資源信號(hào)量消息隊(duì)列首指針name = n;mutex.value = 1;sm.value = 1;mq = NULL;PCB;void P(semaphore& s)s.value-;if(s.value 0)cout 進(jìn)程阻塞 endl;void V(semaphore& s)s.value+;if(s.value = 0)cout 喚醒進(jìn)程 sender消息長(zhǎng)度： q-size 消息正文：q-text next;cout互斥信號(hào)量 mute

5、x ：/z B. mutex, value endl;cout 資源信號(hào)量 sm: B.sm.value endl;cout next = NULL)cout n當(dāng)前緩沖區(qū)為空n endl;elsecout n當(dāng)前消息緩沖區(qū)內(nèi)容:next;int count = 0;while(q != NULL)cout +count .消息發(fā)送者：sender 消 息長(zhǎng)度：size 消息正文：text endl;cout next;void send(PCB &A,message *a) /消息發(fā)送原語(yǔ)message *q = new(message);q-size = a-size;q-sender =

6、 a-sender;q-text = a-text;back-next = q;back = q;q-next = NULL;showBuffer();cout 進(jìn)程 A.name 互斥信號(hào)量執(zhí)行P操作 endl;P(A.mutex);if(A.mq = NULL)cout 消息緩沖區(qū)插入進(jìn)程 A.name 消息隊(duì)列next != NULL)p = p-next;p-next = msg-next;msg-next = NULL;cout緩沖區(qū)清空. endl;cout進(jìn)程A. name互斥信號(hào)量執(zhí)行V操作endl;(A. mutex);cout進(jìn)程A. name資源信號(hào)量執(zhí)行V操作endl;

7、(A. sm);cout /zsend()發(fā)送原語(yǔ)結(jié)束endl;cout endl;voidreceive(PCB&B, message*b)voidreceive(PCB&B, message*b)消息接收原語(yǔ) cout 進(jìn)程 B.name 互斥信號(hào)量執(zhí)行P操作 endl;P(B.mutex);cout 進(jìn)程 B.name 資源信號(hào)量執(zhí)行P操作 endl;P(B.sm);message *p = new(message);if(B.mq = NULL)cout 進(jìn)程 B.name 消息隊(duì)列為空 endl;return;elsecout 消息移出隊(duì)列并刪除sender = B.mq-sende

8、r; /將消息移出消息隊(duì)列p-size = B.mq-size;p-text = B.mq-text;message *q = B.mq-next;/刪除消息隊(duì)列中接收的信息delete(B.mq);B.mq = q;cout 進(jìn)程 B.name 互斥信號(hào)量執(zhí)行V操作 endl;V(B.mutex);cout 進(jìn)程 B.name 消息送入接收區(qū) bsender =p-sender;b-sender =p-size;b-sender =p-text;void createMessage(const PCB &A,message *m)/創(chuàng)建消息m-next = NULL;m-sender = A

9、.name;cout 進(jìn)程 A.name 創(chuàng)建消息 endl;cout m-size m-text;/進(jìn)入消息緩沖區(qū)cout 消息進(jìn)入緩沖區(qū). endl;int main()PCB A(A)；進(jìn)程 APCB B(B)；/進(jìn)程 Bmessage *a = new(message);/消息發(fā)送區(qū)createMessage(A,a);send(B,a);showProcess(B);showBuffer();message *b = new(message);/消息接收區(qū)receive(B,b);return 0;五、運(yùn)行程序、輸出及實(shí)驗(yàn)截圖1、初始化，創(chuàng)建進(jìn)程A、BPCB A(A)； PCB B(B)；2、進(jìn)程A創(chuàng)建消息message *a = new(message);createMessage(A,a);3、發(fā)送消息到進(jìn)程B并查看PCB和消息緩沖區(qū)send(B,a);showProcess(B);showBuffer();4、進(jìn)程B接收消息message *b = new(message);receive(B,b);5、實(shí)驗(yàn)截圖:A褶息長(zhǎng)度壯 nutex：l進(jìn)程B信息-ZZT 1= 11m斥餌M害 桔方里精息正文:眼W昌胃魏薯嚕登I