cannot read correct binaries with tcp sockets

Client sends buffer size along with contents(image file) to the server.(works fine). Server gets the size and contents and loads the image. the client program is follows and it is tested:

QString fileName = "/home/saman/Desktop/1.png";
QFile file(fileName);
if (!file.open(QIODevice::ReadOnly)) return;
QByteArray blob = file.readAll();
file.close();

int size = blob.length();
clientSocket->write((char*)&size, 4);
clientSocket->write(blob.data(), size);

The server program cannot receive the full image file. It reads only 50KB out of 140KB and then read returns 0. I also implemented the code in core C, but, I getting the same result. Here are my implementations:

int size;
 clientConnection->read((char*)&size, 4);
 qDebug() << size;

 char* image;

 qDebug() << size;

 image = new char[size];

 int size2 = size;
 int offset = 0;

 while(size2 > 0)
 {
     int r = clientConnection->read(image+offset, size2);
     if(r == 0)
         break;
     size2 -= r;
     offset += r;
 }

As mentioned,also tried C:

struct sockaddr_in clntaddr, servaddr;       /* my address information */
struct  stat statbuf;
ssize_t bytes_read;
long filesize, chunksize, offset;
int  listenfd, connfd, fd,recv_bytes, fileparts;
socklen_t clntlen;
int  total_parts, optval;
char *buff, filename[128];
pid_t childpid;


if((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1){
    perror("Server-socket() sockfd error lol!");
    exit(1);}
else
    printf("Server-socket() sockfd is OK...\n");

// set SO_REUSEADDR on a socket to true (1):
optval = 1;
setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &optval, sizeof optval);

bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;           /* host byte order */
servaddr.sin_port = htons(SERV_PORT);       /* short, network byte order */
servaddr.sin_addr.s_addr = htonl(INADDR_ANY); /* automatically fill with my IP */
// memset(&(servaddr.sin_zero), '\0', 8);        /* zero the rest of the struct */

if(bind(listenfd, (SA *) &servaddr, sizeof(servaddr)) == -1)
{
    perror("Server-bind() error lol!");
    exit(1);
}
else
    printf("Server-bind() is OK...\n");

if(listen(listenfd, LISTENQ) == -1)
{
    perror("Server-listen() error\n");
    exit(1);
}
else
    printf("Server-listen() is OK \n");

for(;;)
{
    clntlen = sizeof(clntaddr);
    if((connfd = accept(listenfd, (SA *) &clntaddr, &clntlen)) < 0)
    {
        if(errno == EINTR)
            continue;
        else
        {
            printf("server-accept() error\n");
            exit(1);
        }
    }
    else
        printf("server-accept() is OK..\n");


    /*        if((childpid = fork()) == 0)
    { */  // child process

    close(listenfd);                      // close listening socket
    printf("connection established..\n"); // process the request

    if( (recv_bytes = recv(connfd, (void *) &chunksize, sizeof(int), 0))<= 0 )
    {
        if(!recv_bytes)
            printf("socket is blocking and the connection to the remote node failed..\n ");
        else
            printf("Server-recv(Request) error..\n");
        exit(1);
    }

    fileparts = ntohl( chunksize );

    if((fd = open("/home/saman/2.png", O_CREAT | O_WRONLY)) < 0)
    {
        perror("couldn't open the Server-file");
        exit(1);
    }

    buff = (char *)malloc(sizeof(char) * (chunksize));

    if((bytes_read = recv(connfd, (void *)buff, chunksize, 0)) <= 0)
    {
        if(bytes_read < 0)
        {
            perror("Client receiving chunks error..\n");
            exit(1);
        }
    }

    if(write(fd, (void *) buff, bytes_read) <= 0)
    {
        perror("Client writing data error..\n");
        exit(1);
    }

    close(fd)

    if(close(listenfd) != 0)
        printf("Server-listenfd closing failed!\n");
    else
        printf("Server-listenfd successfully closed!\n");


    qDebug() << chunksize;
    qDebug() << buff;
}

I am running client/server program in Linux. The strange part is that server program written by another clerk on windows could load the whole image. Although I have no access to his code, I am wondering where I am doing wrong so that this happens!