Bank

1、介绍

一个计算机系统的消息队列demo

实现一个简单C/S结构的例子。

简单资金账户管理。账户信息：用户名，金额
服务器端提供的功能：能够根据客户端提供的参数，进行相应的操作
提供：
注册：用户名
存款：用户名，本次金额
取款：用户名，本次金额
查询：用户名
用户列表：所有信息

2、实现

bank代码:

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#define MSG_KEY 73
#define SEND_MSG_KEY 74

#define BUFF_SIZE 256

struct msgform
{
    long mtype;
    long pid;
    char mtext[BUFF_SIZE];
} msg;
typedef struct userinfo
{
    char *username;
    double money;
} UserInfo;
typedef struct blank
{
    UserInfo *info;
    int len;
} BlankInfo;
int msgqid, sendqid;
char create[] = "create";
char add[] = "add";
char del[] = "del";
char show[] = "show";
char user[] = "user";

char *getArgment(char *val, int begin, int end)
{
    char *rst = (char *)calloc((end - begin + 1), sizeof(char *));
    int i = 0;
    for (; i < end - begin && val[begin + i] != ' ' && val[begin + i] != '\0'; i++)
    {
        rst[i] = val[begin + i];
    }
    rst[i] = '\0';
    return rst;
}

bool isCreate(char *val, int n)
{
    if (n != 6)
    {
        return false;
    }
    for (int i = 0; i < 6; i++)
    {
        if (val[i] != create[i])
        {
            return false;
        }
    }
    return true;
}

bool isAdd(char *val, int n)
{
    if (n != 3)
    {
        return false;
    }
    for (int i = 0; i < 3; i++)
    {
        if (val[i] != add[i])
        {
            return false;
        }
    }
    return true;
}

bool isDel(char *val, int n)
{
    if (n != 3)
    {
        return false;
    }
    for (int i = 0; i < 3; i++)
    {
        if (val[i] != del[i])
        {
            return false;
        }
    }
    return true;
}

bool isShow(char *val, int n)
{
    if (n != 4)
    {
        return false;
    }
    for (int i = 0; i < 4; i++)
    {
        if (val[i] != show[i])
        {
            return false;
        }
    }
    return true;
}

bool isUser(char *val, int n)
{
    if (n != 4)
    {
        return false;
    }
    for (int i = 0; i < 4; i++)
    {
        if (val[i] != user[i])
        {
            return false;
        }
    }
    return true;
}
BlankInfo *initBlank()
{
    UserInfo *userInfo = (UserInfo *)malloc(sizeof(UserInfo) * BUFF_SIZE);
    BlankInfo *blankInfo = (BlankInfo *)malloc(sizeof(BlankInfo));
    if (userInfo)
    {
        blankInfo->info = userInfo;
        blankInfo->len = 0;
    }
    return blankInfo;
}
UserInfo *getUserInfo(BlankInfo *blank, char *userName)
{
    for (int i = 0; i < blank->len; i++)
    {
        if (!strcmp(blank->info[i].username, userName))
        {
            return &(blank->info[i]);
        }
    }
    return NULL;
}
char *getUserInfoList(BlankInfo *info)
{
    char *rst = (char *)calloc((BUFF_SIZE), sizeof(char *));
    ;
    for (size_t i = 0; i < info->len; i++)
    {
        char flag[256];
        sprintf(flag, "%s %f\n", info->info[i].username, info->info[i].money);
        strcat(rst, flag);
    }
    return rst;
}
int main(void)
{
    printf("blank start!\n");

    extern cleanup();
    for (int i = 0; i < 20; i++)
    {
        signal(i, cleanup);
    }

    msgqid = msgget(MSG_KEY, 0777 | IPC_CREAT);
    sendqid = msgget(SEND_MSG_KEY, 0777 | IPC_CREAT);
    printf("server pid=%d is ready ... msgqid=%d\n", getpid(), msgqid);
    BlankInfo *blank = initBlank();

    int pid;

    while (1)
    {
        msgrcv(msgqid, &msg, sizeof(struct msgform) - sizeof(long), 1, 0);
        pid = msg.pid;
        printf("server:receive from pid=%d string=%s\n", pid, msg.mtext);
        int n = strlen(msg.mtext);
        char *flag = getArgment(msg.mtext, 0, n);
        int flagLen = strlen(flag);
        printf("option is %s,len is %d\n", flag, flagLen);
        if (isCreate(flag, flagLen))
        {
            char *userName = getArgment(msg.mtext, 7, n);
            UserInfo *user = getUserInfo(blank, userName);
            if (user)
            {
                strcpy(msg.mtext, "ERROR,user is exist");
            }
            else
            {
                UserInfo newInfo = {userName, 0};
                blank->info[blank->len] = newInfo;
                blank->len++;
                sprintf(msg.mtext, "Result:create success userName:%s\n", userName);
            }
        }
        else if (isAdd(flag, flagLen))
        {
            char *userName = getArgment(msg.mtext, 4, n);
            int userNameLen = strlen(userName);
            double money = strtod(getArgment(msg.mtext, 5 + userNameLen, n), 0);
            if (money <= 0)
            {
                strcpy(msg.mtext, "ERROR,saving must be more than zero\n");
            }
            else
            {
                UserInfo *user = getUserInfo(blank, userName);
                user->money += money;
                sprintf(msg.mtext, "Result:%s money:%f\n", userName, user->money);
            }
        }
        else if (isDel(flag, flagLen))
        {
            char *userName = getArgment(msg.mtext, 4, n);
            int userNameLen = strlen(userName);
            double money = strtod(getArgment(msg.mtext, 5 + userNameLen, n), 0);
            UserInfo *user = getUserInfo(blank, userName);
            if (money <= 0)
            {
                strcpy(msg.mtext, "ERROR,withdraw must be more than zero\n");
            }
            else if (money > (user->money))
            {
                strcpy(msg.mtext, "ERROR,withdraw must be more than your saving\n");
            }
            else
            {
                user->money -= money;
                printf("send userInfo username:%s money:%f\n", user->username, user->money);
                sprintf(msg.mtext, "Result:username:%s money:%f\n", userName, user->money);
            }
        }
        else if (isShow(flag, flagLen))
        {
            char *userName = getArgment(msg.mtext, 5, n);
            printf("show username %s", userName);
            UserInfo *user = getUserInfo(blank, userName);
            printf("send userInfo username:%s money:%f\n", user->username, user->money);
            sprintf(msg.mtext, "Result:userInfo username:%s money:%f\n", user->username, user->money);
        }
        else if (isUser(flag, flagLen))
        {
            printf("client meed all user info\n");
            strcpy(msg.mtext, getUserInfoList(blank));
        }
        else
        {
            printf("error argment\n");
            strcpy(msg.mtext, "error");
        }

        msg.mtype = pid;
        msg.pid = getpid();
        printf("%s\n", msg.mtext);
        msgsnd(sendqid, &msg, sizeof(struct msgform) - sizeof(long), 0);
        free(flag);
    }
    free(blank->info);
    free(blank);
    return 0;
}
int cleanup()
{
    msgctl(msgqid, IPC_RMID, 0);
    msgctl(sendqid, IPC_RMID, 0);
    exit(0);
    return 0;
}

cilent:

#include <string.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#define MSGKEY 73
#define SENDKEY 74

struct msgform
{
    long mtype;
    long pid;
    char mtext[256];
};
int main(void)
{
    struct msgform msg;
    int msgqid, sendqid, pid, *pint;

    msgqid = msgget(MSGKEY, 0777);
    sendqid = msgget(SENDKEY, 0777);
    pid = getpid();
    printf("cilent start\n");

    while (1)
    {
        printf("please input commond:\n");
        gets(msg.mtext);

        if (msg.mtext[0] == 'q')
        {
            break;
        }
        if (msg.mtext[0] == 'h')
        {
            printf("createuser:create [username]\n");
            printf("addmoney:add [username] [money]\n");
            printf("delmoney:del [username] [money]\n");
            printf("showuser:show [username]\n");
            printf("showall:user\n");
        }
        else
        {
            msg.mtype = 1;
            msg.pid = pid;
            msgsnd(msgqid, &msg, sizeof(struct msgform) - sizeof(long), 0);
            msgrcv(sendqid, &msg, sizeof(struct msgform) - sizeof(long), pid, 0);
            printf("blank:\n%s\n", msg.mtext);
        }
    }
    printf("ending\n");
    return 0;
}

运行效果：

等等。。。