linux信号量机制.doc

Linux信号量机制1 需求说明l 提供与用户交互的界面，用户可指定输入、输出文件以及缓冲区大小l 利用信号量实现互斥l 同时产生多个get、copy和put线程，利用信号量实现多个相同功能的线程间的通信，避免临界资源的非法访问l 支持文件输入、输出2 设计说明缓冲区S缓冲区Tgetcopyput2.1 结构设计2.2 功能设计l 提供与用户交互的界面，用户可指定输入、输出文件以及缓冲区大小l 利用信号量实现互斥l 同时产生多个get、copy和put线程，利用信号量实现多个相同功能的线程间的通信，避免临界资源的非法访问l 支持文件输入、输出3 测试和使用说明3.1 使用说明把相应文件都放在同一个文件夹内，然后使用make工具编译，生成mycopy可执行文件即可。3.2 测试说明用信号量实现互斥，同时产生多个get、copy和put线程，利用信号量实现多个同功能的线程间的通信，避免临界资源的非法访问。4 程序清单Makefilemycopy:main.c interface.o Get.o Copy.o Put.o def.hgcc main.c interface.o Get.o Copy.o Put.o -lpthread -o mycopyinterface.o:interface.c def.hgcc -c interface.c -lpthread -o interface.oGet.o:Get.c def.hgcc -c -lpthread Get.c -o Get.oCopy.o:Copy.c def.hgcc -c -lpthread Copy.c -o Copy.oPut.o:Put.c def.hgcc -c -lpthread Put.c -o Put.o/*def.h*/#ifndef DEF_H#define DEF_H#include#include#include#include#include#include#include#include#include #include #include#define BUF_SIZE 1024#define P(x) sem_wait(x)#define V(x) sem_post(x)extern int InFD,OutFD;extern int BufferSize;extern sem_t Tempty,Sempty,Sfull,Tfull;extern char *BufferS,*BufferT;extern int Slen,Tlen;void ppput(void);void ccopy(void);void ggget(void);#endif/*main.c*/#include def.hint InFD,OutFD;int BufferSize=BUF_SIZE;sem_t Tempty,Sempty,Sfull,Tfull;char *BufferS,*BufferT;int Slen,Tlen;void initSem() sem_init(&Sempty,1,1); sem_init(&Sfull,1,0); sem_init(&Tfull,1,0); sem_init(&Tempty,1,1);void initBuffer() BufferT=(char*)malloc(sizeof(char)*BufferSize); assert(BufferT!=NULL); BufferS=(char*)malloc(sizeof(char)*BufferSize); assert(BufferS!=NULL); Slen=Tlen=0;int main() interface(); initSem(); initBuffer(); pthread_t gid,cid,pid; pthread_create(&gid,NULL,(void *)ggget,NULL); pthread_create(&cid,NULL,(void *)ccopy,NULL); pthread_create(&pid,NULL,(void *)ppput,NULL); pthread_join(gid,NULL); pthread_join(cid,NULL); pthread_join(pid,NULL); return 0;/*Get.c */#include def.hvoid ggget() int fuck=1; while(fuck) P(&Sempty); Slen=read(InFD,BufferS,BufferSize); fuck=(Slen!=0); V(&Sfull); /*Copy.c */#include def.hvoid ccopy() int wtf=1; while(wtf) P(&Sfull); P(&Tempty); memcpy(BufferT,BufferS,Slen); Tlen=Slen; wtf=(Slen!=0); V(&Sempty); V(&Tfull); /*Put.c */#include def.hvoid ppput() int wocao=1; while(wocao) P(&Tfull); if(Tlen)write(OutFD,BufferT,Tlen); else wocao=0; V(&Tempty); /*mysem.c */#include def.h#define SEGSIZE 1024#define READTIME 1union semun int val; struct semid_ds *buf; unsigned short *array; arg;/生成信号量int sem_creat(key_t key)union semun sem;int semid;sem.val = 0;semid = semget(key,1,IPC_CREAT|0666);if (-1 = semid)printf(create semaphore errorn);exit(-1);semctl(semid,0,SETVAL,sem);return semid;/删除信号量void del_sem(int semid)union semun sem;sem.val = 0;semctl(semid,0,IPC_RMID,sem);/pint P(int semid)struct sembuf sops=0,+1,IPC_NOWAIT;return (semop(semid,&sops,1);/vint