all.txt

这是在linux环境下C++做的生产者和消费者问题

/**
抽烟问题：
材料区：一个共享内存单元—material，保存提供的材料；供应者填充，抽烟者消费；供应者靠
       empty，抽烟者靠full实现同步；
供应者：通过一共享内存保存上次提供的材料，以循环提供，供应者之间靠pro-multex互斥；
抽烟者：不停查询material中是否是自己所需的材料，如果是唤醒供应者，如果不是则继续等待；
       抽烟者靠cons-multex互斥；
信号量初值：
       empty=1，full=0，pro-multex=1,cons-multex=1；
*/
/*******************************ipc.h**********************************************/
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/sem.h>
#include <sys/msg.h>

#define BUFSZ 256

/*
* the functions to get the shared memary and the semaphore
*/
int get_ipc_id(char *proc_file,key_t key);
char *set_shm(key_t shm_key,int shm_num,int shm_flag);
int set_sem(key_t sem_key,int sem_val,int sem_flag);
int operationP(int sem_id);
int operationV(int sem_id);
/*
* semaphore control union
*/
typedef union semuns{
    int val;
}Sem_uns;
typedef struct msgbuf{
    long mtype;
    char *mtext;
} Msg_buf;
/**
* the variables needed by the producers and the consumers
*/
key_t buff_key;/*material's key*/
int i;
int buff_num;
int *buff_ptr;
int buff_flag;
key_t full_key;
key_t empty_key;
key_t pro_ex_key;
key_t cons_ex_key;
int full_value;
int empty_value;
int pro_ex_value;
int cons_ex_value;
int full_sem;
int empty_sem;
int pro_ex_sem;
int cons_ex_sem;
int sem_flag;
/*********************ipc.h end******************/



/*******************************ipc.c*******************************************/
#include "ipc.h"

int get_ipc_id(char *proc_file,key_t key){
    FILE *pf;
    int i,j;
    char line[BUFSZ],colum[BUFSZ];
    if((pf=fopen(proc_file,"r"))==NULL){
        perror("proc file not open");
        exit(EXIT_FAILURE);
    }
    /*fgets(line,BUFSZ,pf);*/
    while(!feof(pf)){
        i=j=0;
        fgets(line,BUFSZ,pf);
        while(line[i]==' ')i++;
        while(line[i]!=' ')colum[j++]=line[i++];
        colum[j]='\0';
        if(atoi(colum)!=key)continue;
        j=0;
        while(line[i]==' ')i++;
        while(line[i]!=' ')colum[j++]=line[i++];
        colum[j]='\0';
        i=atoi(colum);
        fclose(pf);
        return i;
    }
    fclose(pf);
    return -1;
}
int operationP(int sem_id){
    struct sembuf buf;
    buf.sem_op=-1;
    buf.sem_num=0;
    buf.sem_flg=600;
    if((semop(sem_id,&buf,1))<0){
        perror("operationP error");exit(EXIT_FAILURE);
    }
    return EXIT_SUCCESS;
}
int operationV(int sem_id){
    struct sembuf buf;
    buf.sem_op=1;
    buf.sem_num=0;
    buf.sem_flg=600;
    if((semop(sem_id,&buf,1))<0){
        perror("operationV error");exit(EXIT_FAILURE);
    }
    return EXIT_SUCCESS;
}
int set_sem(key_t sem_key,int sem_val,int sem_flg){
    int sem_id;
    Sem_uns sem_arg;
    if((sem_id=get_ipc_id("/proc/sysvipc/sem",sem_key))<0){
        /* to create a new semaphore */
        if((sem_id=semget(sem_key,1,sem_flg))<0){
            perror("semaphore create error");exit(EXIT_FAILURE);
        }
        sem_arg.val=sem_val;
        if(semctl(sem_id,0,SETVAL,sem_arg)<0){
            perror("semaphore set error");exit(EXIT_FAILURE);
        }
    }
    return sem_id;
}
char *set_shm(key_t shm_key,int shm_num,int shm_flg){
    int i,shm_id;
    char *shm_buf;
    if((shm_id=get_ipc_id("/proc/sysvipc/shm",shm_key))<0){
        /* to create a new shared memary */
        if((shm_id=shmget(shm_key,shm_num,shm_flg))<0){
            perror("shared memary create error");exit(EXIT_FAILURE);
        }
        if((shm_buf=(char*)shmat(shm_id,0,0))<(char*)0){
            perror("sharedmemary get error");exit(EXIT_FAILURE);
        }
        for(i=0;i<shm_num;i++)shm_buf[i]=0;
    }
    if((shm_buf=(char*)shmat(shm_id,0,0))<(char*)0){
        perror("sharedmemary get error");exit(EXIT_FAILURE);
    }
    return shm_buf;
}
/*****************ipc.c end*******************/




/******************************consumer.c**********************************/
#include "ipc.h"
int main(int arc,char *argv[]){
    /**
    * this producer doesn't sleep
    */
   
    int count=0;
    int material;
    buff_key=101;
    buff_num=sizeof i;
    buff_flag=IPC_CREAT|0644;
    full_key=201;
    empty_key=202;
    pro_ex_key=301;
    cons_ex_key=302;
    full_value=0;
    empty_value=1;
    pro_ex_value=1;
    cons_ex_value=1;
    sem_flag=IPC_CREAT|0644;
    printf("enter the material this consumer need:");
    scanf("%d",&material);
    buff_ptr=(int*)set_shm(buff_key,buff_num,buff_flag);
   
    full_sem=set_sem(full_key,full_value,sem_flag);
    empty_sem=set_sem(empty_key,empty_value,sem_flag);
    cons_ex_sem=set_sem(cons_ex_key,cons_ex_value,sem_flag);
    while(count++<8){
        while(1){
            sleep(1);
            operationP(full_sem);
            operationP(cons_ex_sem);
            if(buff_ptr[0]==material){
                printf("costomer:%d getting %d\n",getpid(),material);
                operationV(cons_ex_sem);
                printf("costomer:%d signal empty\n",getpid());
                operationV(empty_sem);
                break;
                                 }
            operationV(full_sem);
            operationV(cons_ex_sem);
                    }
         }
}
 
/*************con.c end**********************/




/******************************producer.c**********************************/
#include "ipc.h"
int main(int arc,char *argv[]){

key_t buff_key=101;/*material's key*/
    int count=0;
    buff_num=sizeof i;
    buff_flag=IPC_CREAT|0644;
    buff_key=101;

    full_key=201;
    empty_key=202;
    pro_ex_key=301;
    cons_ex_key=302;
    full_value=0;
    empty_value=1;
    pro_ex_value=1;
    cons_ex_value=1;
    sem_flag=IPC_CREAT|0644;

    buff_ptr=(int*)set_shm(buff_key,buff_num,buff_flag);
   
    full_sem=set_sem(full_key,full_value,sem_flag);
    empty_sem=set_sem(empty_key,empty_value,sem_flag);
    pro_ex_sem=set_sem(pro_ex_key,pro_ex_value,sem_flag);
    while(count++<12){
        sleep(2);
        operationP(empty_sem);
        operationP(pro_ex_sem);
        printf("producer %d sending %d\n",getpid(),((buff_ptr[0]+1)%3));
        buff_ptr[0]=(buff_ptr[0]+1)%3;
        operationV(full_sem);
        operationV(pro_ex_sem);
         }
}