Technology sharing

한어Русский языкEnglishFrançaisIndonesianSanskrit日本語DeutschPortuguêsΕλληνικάespañolItalianoSuomalainenLatina

Udp processus programmandi

Sento non angustos

Intellego chat cubiculum effectus

online

chat

offline

Servo indiget inscriptione ut nomen retineat et IP electronica

Mitte structuram in commercio

Macro sequenti nonnisi in C lingua adhiberi potest

ser.sin_port = htons(50000);

Portus supra numerum supra 50000 est, idemque ex utraque parte esse debet.

Hic ne nimis celeriter mittere UDP est, illic aliquid mittere

Missio et acceptio pluries idem esse debet.

stateless

Cur latus dextrum intra comparationem finis signorum scriptum est?

Verificatur quod notitia missa et recepta ab UDP terminos habet

Netstat potes network status

Service-Terminal

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <time.h>
typedef struct sockaddr * (SA);
typedef enum {CMD_LOGIN,CMD_CHAT,CMD_LOGOUT}TYPE;
typedef struct 
{
    TYPE type;
    char name[50];
    char context[128];
 
}MSG;
typedef struct 
{
    struct sockaddr_in cli;
    int flag; // 0  free 1 occu
}LIST;
#define MAX 10
LIST list[MAX]={0};
int do_login(int sockfd,MSG* msg,struct sockaddr_in* cli)
{
    int i = 0 ;
    for(i=0;i<MAX;i++)
    {
        if(1 == list[i].flag )
        {
            sendto(sockfd,msg,sizeof(MSG),0,(SA)&list[i].cli,sizeof(list[i].cli));
        }
    }
    for(i=0;i<MAX;i++)
    {
        if(0 == list[i].flag )
        {
            list[i].flag =1;
            //list[i].cli = *cli;
            memcpy(&list[i].cli,cli,sizeof(*cli));
            break;
        }
    }
    return 0;
}
 
int do_chat(int sockfd, MSG* msg,struct sockaddr_in*cli)
{
     int i = 0 ;
    for(i=0;i<MAX;i++)
    {
        if(1 == list[i].flag && 0!=memcmp(&list[i].cli,cli,sizeof(*cli)) )
        {
            sendto(sockfd,msg,sizeof(MSG),0,(SA)&list[i].cli,sizeof(list[i].cli));
        }
    }
}
int do_logout(int sockfd, MSG* msg,struct sockaddr_in*cli)
{
    return 0;
}
int main(int argc, char *argv[])
{
    int sockfd = socket(AF_INET,SOCK_DGRAM,0);
    if(-1 == sockfd)
    {
        perror("socket");
        exit(1);
    }
 
    // man 7 ip 
    struct sockaddr_in ser,cli;
    bzero(&ser,sizeof(ser));
    bzero(&cli,sizeof(cli));
    ser.sin_family = AF_INET;
    // 大小端转化 host to net short 
    ser.sin_port = htons(50000);
    ser.sin_addr.s_addr = inet_addr("127.0.0.1");
    int ret = bind(sockfd,(SA)&ser,sizeof(ser));
    if(-1 == ret)
    {
        perror("bind");
        exit(1);
    }
    socklen_t len = sizeof(cli);
    MSG msg;
    while(1)
    {
        bzero(&msg,sizeof(msg));
        recvfrom(sockfd,&msg,sizeof(msg),0,(SA)&cli,&len);
        switch(msg.type)
        {
            case CMD_LOGIN:
                do_login(sockfd,&msg,&cli);
                break;
            case CMD_LOGOUT:
                do_logout(sockfd,&msg,&cli);
                break;
            case CMD_CHAT:
                do_chat(sockfd,&msg,&cli);
                break;
        
        }
    }
    close(sockfd);
    return 0;
}

user terminatio

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <time.h>
typedef struct sockaddr * (SA);
typedef enum {CMD_LOGIN,CMD_CHAT,CMD_LOGOUT}TYPE;
typedef struct 
{
    TYPE type;
    char name[50];
    char context[128];
 
}MSG;
int main(int argc, char *argv[])
{
    int sockfd = socket(AF_INET,SOCK_DGRAM,0);
    if(-1 == sockfd)
    {
        perror("socket");
        exit(1);
    }
 
    // man 7 ip 
    struct sockaddr_in ser,cli;
    bzero(&ser,sizeof(ser));
    ser.sin_family = AF_INET;
    // 大小端转化 host to net short 
    ser.sin_port = htons(50000);
    ser.sin_addr.s_addr = inet_addr("127.0.0.1");
    socklen_t len = sizeof(cli);
    MSG msg;
    char name[50]={0};
    printf("input name:");
    fgets(name,sizeof(name),stdin);
    name[strlen(name)-1]='0';
 
    msg.type = CMD_LOGIN;
    strcpy(msg.name ,name);
    strcpy(msg.context,"login");
 
    sendto(sockfd,&msg,sizeof(msg),0,(SA)&ser,sizeof(ser));
 
    pid_t pid = fork();
    if(pid>0)
    {
        while(1)
        {
            bzero(&msg,sizeof(msg));
            recvfrom(sockfd,&msg,sizeof(msg),0,NULL,NULL);    
            printf("%s:%sn",msg.name,msg.context);
        }
    }
    else if(0==pid)
    {
        while(1)
        {
            printf("to all");    
            char buf[128]={0};
            strcpy(msg.name,name);
            msg.type = CMD_CHAT;
            fgets(msg.context,sizeof(msg.context),stdin);//#quit
            msg.context[strlen(msg.context)-1]='0';
            if(0==strcmp(msg.context,"#quit"))
            {
                msg.type = CMD_LOGOUT;
                strcpy(msg.context,"CMD_LOGOUT");
            }
            sendto(sockfd,&msg,sizeof(msg),0,(SA)&ser,sizeof(ser));
        }
    }
    else 
    {
        perror("fork");
        exit(1);
    }
    close(sockfd);
    return 0;
}