server-client-network/client.c

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#define __USE_MISC
#include <arpa/inet.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <signal.h>

#include "Stream.h"

#define BUFFER_SIZE 1024
#define PORT 6543

int clientSocket = -1;

void cleanUp()
{
    if(clientSocket != -1)
    {
        if(close(clientSocket) != 0)
        {
            perror("Cannot close client socket");
        }
        else
        {
            printf("socket closed\n");
        }
    }
}

void interruptHandler(int signal)
{
    cleanUp();
    exit(EXIT_SUCCESS);
}

void safeExit(int status)
{
    cleanUp();
    exit(status);
}

int main(int argc, char **argv)
{
    signal(SIGINT, interruptHandler);
    signal(SIGKILL, interruptHandler);

    char buffer[BUFFER_SIZE];
    int size;

    if(argc < 2)
    {
        printf("Usage: %s server_address\n", argv[0]);
        safeExit(EXIT_FAILURE);
    }

    clientSocket = socket(AF_INET, SOCK_STREAM, 0);
    if(clientSocket == -1)
    {
        perror("Cannot create socket");
        safeExit(EXIT_FAILURE);
    }

    struct sockaddr_in clientSocketData;
    memset(&clientSocketData, 0, sizeof (clientSocketData));
    clientSocketData.sin_family = AF_INET;
    clientSocketData.sin_port = htons(PORT);
    if(inet_aton(argv[1], &clientSocketData.sin_addr) == 0)
    {
        printf("'%s' is not a valid ip\n", argv[1]);
        safeExit(EXIT_FAILURE);
    }

    if(connect(clientSocket, (struct sockaddr*) &clientSocketData, sizeof(clientSocketData)) == 0)
    {
        printf("Connection with server (%s) established\n", inet_ntoa(clientSocketData.sin_addr));
        size = recv(clientSocket, buffer, BUFFER_SIZE - 1, 0);
        if(size > 0)
        {
            buffer[size] = '\0';
            printf("%s", buffer);
            if(strncmp(buffer, "error", 5) == 0)
            {
                safeExit(EXIT_FAILURE);
            }
        }
    }
    else
    {
        perror("No server is available");
        safeExit(EXIT_FAILURE);
    }

    while(strcmp(buffer, "quit\n") != 0)
    {
        printf("Send message: ");
        fgets(buffer, BUFFER_SIZE, stdin);
        
        Stream out;
        out.index = 0;
        out.size = BUFFER_SIZE;
        streamWriteChar(0, &out);
        streamWriteInt(-423, &out);
        streamWriteInt(-6456463, &out);
        streamWriteInt(443534, &out);
        streamWriteInt(75676, &out);
        
        if(send(clientSocket, out.data, out.index, MSG_NOSIGNAL) == -1)
        {
            perror("Cannot send data");
            break;
        }
    }
    
    safeExit(EXIT_SUCCESS);
    return EXIT_SUCCESS;
}