real_time/software/raspberry/superviseur-robot/lib/src/server.cpp

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/* 
 * File:   server.cpp
 * Author: dimercur
 * 
 * Created on 19 octobre 2018, 14:24
 */

#include "server.h"
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

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

#define NB_CONNECTION_MAX 1

int socketFD = -1;
int clientID = -1;

int openServer(int port) {
    struct sockaddr_in server;

    socketFD = socket(AF_INET, SOCK_STREAM, 0);
    if (socketFD < 0) {
        perror("Can not create socket");
        exit(-1);
    }

    server.sin_addr.s_addr = INADDR_ANY;
    server.sin_family = AF_INET;
    server.sin_port = htons(port);

    if (bind(socketFD, (struct sockaddr *) &server, sizeof (server)) < 0) {
        perror("Can not bind socket");
        exit(-1);
    }

    listen(socketFD, NB_CONNECTION_MAX);

    return socketFD;
}

int closeServer() {
    close(socketFD);

    socketFD = -1;
    
    return 0;
}

int acceptClient() {
    struct sockaddr_in client;
    int c = sizeof (struct sockaddr_in);

    clientID = accept(socketFD, (struct sockaddr *) &client, (socklen_t*) & c);

    if (clientID < 0) {
        perror("Accept failed in acceptClient");
        exit(-1);
    }

    return clientID;
}

int sendDataToServer(char *data, int length) {
    return sendDataToServerForClient(clientID, data, length);
}

int sendDataToServerForClient(int client, char *data, int length) {
    if (client >= 0)
        return write(client, (void*)data, length);
    else return 0;
}

int receiveDataFromServer(char *data, int size) {
    return receiveDataFromServerFromClient(clientID, data, size);
}

int receiveDataFromServerFromClient(int client, char *data, int size) {
    char length = 0;

    if (client > 0) {
        if ((length = recv(client, (void*)data, size, 0)) > 0) {
            data[length] = 0;
        }
    }

    return length;
}