10 port management of switch background management

Project requirements

Switch

Port:

1) Port name
2) Port status
3) IP address of the port
4) Port type
WAN
LAN

Project realization

1. Add menu frame

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

FILE *file; 

void init(void) {
    //Open file
    file = fopen("users.txt", "r");   
    if (!file) {   //Equivalent to file == NULL  
        printf("File open failed");
        //return 1;
        exit(1);
    }
}

void login(void) {
    char name[32];
    char password[16];
    char line[128];
    char name_tmp[32];
    char password_tmp[16];
    char *ret;

    //Enter user name and password
    while (1) {
        system("cls");

        // Enter user name and password
        printf("Please enter the user name:");
        scanf("%s", name);
        printf("Please input a password:");
        scanf("%s", password);

        //Read the account from the file and judge!
        while (1) {
            //Read a row
            ret = fgets(line, sizeof(line), file); //line:  "admin 123456\n"
            if (!ret) {
                break;
            }           
            sscanf(line, "%s %s", name_tmp, password_tmp);
            if (!strcmp(name, name_tmp) && !strcmp(password, password_tmp)) {
                break;
            }
        }

        if (ret) {  //User name and password match successfully
            break;
        } else {
            printf("Wrong user name or password!\n");  
            system("pause");
            system("cls");

            fseek(file, 0, SEEK_SET); //Set the location pointer inside the file to the file header
        }
    }
}

void create_user(void) {
    system("cls");
    printf("\n\n---Create account---\n\n");
    printf("To be realized...\n\n");
    printf("\n\n Press any key to return to the main menu");
    fflush(stdin);
    getchar();
}

void ip_admin(void) {
    system("cls");
    printf("\n\n---IP Administration---\n\n");
    printf("To be realized...\n\n");
    printf("\n\n Press any key to return to the main menu");
    fflush(stdin);
    getchar();
}

void logout(void) {
    system("cls");
    fclose(file);
    exit(0);
}

void input_error(void) {
    system("cls");
    printf("\n\n Input error!\n\n");
    printf("\n\n After pressing any key, please re-enter\n\n");
    fflush(stdin);
    getchar();
}

void show_memu(void) {
    system("cls");
    // Print function menu
    printf("---Switch background management---\n");
    printf("1. Create account\n");
    printf("2. IP Administration\n");
    printf("3. Sign out\n");
    printf("4. Port management\n");
    printf("Please choose: ");
}

void show_ports(void) {
    system("cls");
    printf("---port status---\n");
    printf("To be realized.\n");
    system("pause");
}

void set_ports(void) {
    system("cls");
    printf("---port settings---\n");
    printf("To be realized.\n");
    system("pause");
}

void port_admin(void) {
    char n;

    while(1) {
        system("cls");
        printf("1. View port\n");
        printf("2. Set port\n");
        printf("3. Back to main menu\n");
        printf("Please choose: ");

        fflush(stdin);
        scanf("%c", &n);
        if (n == '1') {
            show_ports();
        } else if (n == '2') {
            set_ports();
        } else if (n == '3') {
            break;
        } else {
            input_error();
        } 
    }
}

int main(void) {
    char n; //User selected menu number

    init(); //Initialization
    login(); //Sign in

    while (1) {
        show_memu();

        fflush(stdin);
        scanf("%c", &n);
        switch (n) {
        case '1':
            create_user();
            break;
        case '2':
            ip_admin(); 
            break;
        case '3':
            logout();
            break;
        case '4':
            port_admin();
            break;
        default:
            input_error();
            break;
        }
    }

    return 0;
}

2. Representation of port information
Add type definition and port variables

struct port {
    char name[16];  //Name of the port
    int  status; //1: Activate 0: Disable
    char ip[16];  //192.168.1.5
    char type[4];  //Port type LAN WAN
};

//Five port variables are defined
struct port port1;
struct port port2;
struct port port3;
struct port port4;
struct port port5;

Project realization

void show_port(struct port port) {
    printf("Name[%s]\t state[%s]\tIP[%s]\t type[%s]\n", 
        port.name,
        port.status == 0 ? "Prohibit":"activation",
        port.ip,
        port.type);
}

void show_ports(void) {
    system("cls");
    printf("---port status---\n");

    printf("PORT1:\t");
    show_port(port1);

    printf("PORT2:\t");
    show_port(port2);

    printf("PORT3:\t");
    show_port(port3);

    printf("PORT4:\t");
    show_port(port4);

    system("pause");
}

void set_port1(void) {
    system("cls");
    printf("---Set up PORT1 port---\n");

    printf("Please enter the port name: ");
    scanf("%s", port1.name);

    printf("Please enter the status of the port:[0:prohibit] [1:activation] ");
    scanf("%d", &port1.status);

    printf("Please enter the type of port:[LAN or WAN] ");
    scanf("%s", port1.type);

    printf("Please enter the IP address: ");
    scanf("%s", port1.ip);

    system("pause");
}

void set_port2(void) {
    system("cls");
    printf("---Set up PORT2 port---\n");

    printf("Please enter the port name: ");
    scanf("%s", port2.name);

    printf("Please enter the status of the port:[0:prohibit] [1:activation] ");
    scanf("%d", &port2.status);

    printf("Please enter the type of port:[LAN or WAN] ");
    scanf("%s", port2.type);

    printf("Please enter the IP address: ");
    scanf("%s", port2.ip);
}

void set_port3(void) {
    system("cls");
    printf("---Set up PORT3 port---\n");

    printf("Please enter the port name: ");
    scanf("%s", port3.name);

    printf("Please enter the status of the port:[0:prohibit] [1:activation] ");
    scanf("%d", &port3.status);

    printf("Please enter the type of port:[LAN or WAN] ");
    scanf("%s", port3.type);

    printf("Please enter the IP address: ");
    scanf("%s", port3.ip);
}

void set_port4(void) {
    system("cls");
    printf("---Set up PORT4 port---\n");

    printf("Please enter the port name: ");
    scanf("%s", port4.name);

    printf("Please enter the status of the port:[0:prohibit] [1:activation] ");
    scanf("%d", &port4.status);

    printf("Please enter the type of port:[LAN or WAN] ");
    scanf("%s", port4.type);

    printf("Please enter the IP address: ");
    scanf("%s", port4.ip);
}

void set_port5(void) {
    system("cls");
    printf("---Set up PORT5 port---\n");

    printf("Please enter the port name: ");
    scanf("%s", port5.name);

    printf("Please enter the status of the port:[0:prohibit] [1:activation] ");
    scanf("%d", &port5.status);

    printf("Please enter the type of port:[LAN or WAN] ");
    scanf("%s", port5.type);

    printf("Please enter the IP address: ");
    scanf("%s", port5.ip);
}

void set_ports(void) {
    char n;

    while(1) {
        system("cls");
        printf("---port settings---\n");
        printf("1. PORT1\n");
        printf("2. PORT2\n");
        printf("3. PORT3\n");
        printf("4. PORT4\n");
        printf("5. PORT5\n");
        printf("6. Return\n");
        printf("Please choose: ");

        fflush(stdin);
        scanf("%c", &n);
        switch (n) {
        case '1':
            set_port1();
            break;
        case '2':
            set_port2();
            break;
        case '3':
            set_port3();
            break;
        case '4':
            set_port4();
            break;
        case '5':
            set_port5();
            break;
        case '6':
            return;
        default:
            input_error();
            break;
        } 
    }

}

Project presentation

1. Why use structure (structure)
However, it is not convenient to use a simple data type when you need to represent some replication information.

For example: student information (student number, name, class, phone number, age)

2. What is "structure"
Structure is a kind of "data type" defined by programmers
It is a new "data type" composed of several basic data types or other structures.

3. Definition of structure
struct structure name{
Member type member name;
Member type member name;
};

Example:

struct  student {
   char  name[16];
   int   age;
   char  tel[12];
};

Special attention:

1) Start with struct
2) Last use semicolon
3) Members are separated by semicolons

4. Initialization of structure

demo

#include <stdio.h>

struct student {
    char name[16];
    int age;
};

int main(void) {
    struct student s1 = {
        "Rock", 38
    };

    struct student s2 = {
        .age = 100,
        .name = "Zhang Sanfeng"
    };

    struct student s3;
    s3.age = 40;
    strcpy(s3.name, "Yang Guo");

    printf("%s, %d\n", s1.name, s1.age);
    printf("%s, %d\n", s2.name, s2.age);
    printf("%s, %d\n", s3.name, s3.age);
    return 0;
}

5. Use of structure

// Defining structural variables
// Note: the full type name is struct student 
//       Not just student s
struct  student  s1，s2;
struct  student  s3;

scanf("%s",  s1.name);
s1.name = 25;   

s2 = s1;  //Direct assignment between structural variables

Usage:
Structural variables. Member variables
Separated by

6. Use structure as function parameter

#include <stdio.h>
#include <string.h>

struct  student {
   char  name[16];
   int   age;
   char  tel[12];
};

void work(struct student stu) {
    stu.age++;
    printf("%s,%d\n", stu.name, stu.age);
}

int main(void) {
    struct student s;

    strcpy(s.name, "Rock");
    s.age = 38;

    work(s); //Structure variable s as a function parameter does not change the value of S itself
    printf("%s,%d\n", s.name, s.age);

    return 0;
}

Be careful:
It is generally not recommended to take the structure as a function parameter directly.
Because the size of the structure is relatively large, it can directly transfer and consume performance!
Solution (using pointers)

7. Global variable, local variable

test1.c

#include <stdio.h>

void east_travel(void);

char master[16] = "Nu Wa";

void west_travel(void) {
    char master[16] = "Tang Seng";
    printf("[Westward Journey]Boss is: %s\n", master);
}

int main(void) {
    char master[16] = "Buddha";

    printf("[main]Boss is: %s\n", master);

    char c;
    printf("Enter the country of daughters? ( Y or N)\n");
    fflush(stdin);
    scanf("%c", &c);
    if (c=='Y' || c=='y') {
        char master[16] = "Queen";
        printf("[main-Daughter country]Boss is: %s\n", master);
    }

    printf("[main]Boss is: %s\n", master);

    east_travel();
    return 0;
}

test2.c

#include <stdio.h>

extern char master[16];  //Cannot initialize! Indicates that this global variable is defined in other files!

void east_travel(void) {
    printf("[East tour]Boss is: %s\n", master);
}

gcc test1.c test2.c

Project practice

Exercise 1

Independent implementation project 10

Exercise 2

1. Define a structure to describe the basic information of a game character.
The role information includes: name, gender, force value
And let the user enter 1 role.
The operation effect is as follows:

Reference code:

#include <stdio.h>

struct role {
    char name[32];
    char sex; //'M': Male 'W': Female 
    int power; 
};

int main(void) {
    struct role  r1, r2;

    printf("Please enter the name of the role: ");
    scanf("%s", r1.name);

    fflush(stdin);
    printf("Please enter the gender of the role: ");
    scanf("%c", &r1.sex);

    printf("Please enter the force value of the role: ");
    scanf("%d", &r1.power);

    printf("\n===Role setting===\n");
    printf("Full name: %s\n", r1.name);
    printf("Gender:%c\n", r1.sex);
    printf("Force value:%d\n", r1.power);

    return 0;
}