C - Socket : Programmation Client/Serveur Application pour envoyer un fichier

Ajouter une gestion d'erreur dans votre code, cela devrait vous aider à repérer le problème. Notez également que send(), recv(), fread() et fwrite() ne sont pas garantis pour écrire/lire l'intégralité de la mémoire tampon que vous spécifiez, de sorte que vous devriez prendre en considération aussi bien.

Aussi, depuis, le protocole TCP est un flux d'octets, le serveur doit indiquer le moment où le fichier se termine ainsi, le client sait quand s'arrêter de lire. Si vous n'envoyez pas de la taille du fichier avant d'envoyer le fichier, la seule option est de fermer le socket lorsque le transfert est terminé.

Essayer quelque chose comme cela:

int send_all(int sock, const void *buf, int len)
{
const char *pbuf = (const char *) buf;
while (len > 0)
{
int sent = send(sock, pbuf, len, 0);
if (sent < 1)
{
//if the socket is non-blocking, then check
//the socket error for WSAEWOULDBLOCK/EAGAIN
//(depending on platform) and if true then
//use select() to wait for a small period of
//time to see if the socket becomes writable
//again before failing the transfer...
printf("Can't write to socket");
return -1;
}
pbuf += sent;
len -= sent;
}
return 0;
}
void str_server(int sock) 
{ 
char buf[0x1000]; 
const char* filename = "test.text";
struct stat s;
if (stat(filename, &s) == -1)
{
printf("Can't get file info"); 
return;
}
FILE *file = fopen(filename, "rb"); 
if (!file)
{
printf("Can't open file for reading"); 
return;
}
//if you need to handle files > 2GB,
//be sure to use a 64bit integer, and
//a host-to-network function that can
//handle 64bit integers...
long size = s.st_size;
long tmp_size = htonl(size);
if (send_all(sock, &tmp_size, sizeof(tmp_size)) == 0)
{
while (size > 0)
{ 
int rval = fread(buf, 1, min(sizeof(buf), size), file); 
if (rval < 1)
{
printf("Can't read from file");
break;
}
if (send_all(sock, buf, rval) == -1)
break;
size -= rval;
}
}
fclose(file);
} 

int write_all(FILE *file, const void *buf, int len)
{
const char *pbuf = (const char *) buf;
while (len > 0)
{
int written = fwrite(pbuf, 1, len, file);
if (written < 1)
{
printf("Can't write to file");
return -1;
}
pbuf += written;
len -= written;
}
return 0;
}
int read_all(int sock, void *buf, int len)
{
char *pbuf = (char *) buf;
int total = 0;
while (len > 0)
{
int rval = recv(sock, pbuf, len, 0);
if (rval < 0)
{
//if the socket is non-blocking, then check
//the socket error for WSAEWOULDBLOCK/EAGAIN
//(depending on platform) and if true then
//use select() to wait for a small period of
//time to see if the socket becomes readable
//again before failing the transfer...
printf("Can't read from socket");
return -1;
}
if (rval == 0)
{
printf("Socket disconnected")
return 0;
} 
pbuf += rval;
len -= rval;
total += rval;
}
return total;
}
void RecvFile(int sock, const char* filename) 
{ 
int rval; 
char buf[0x1000];
FILE *file = fopen(filename, "wb"); 
if (!file)
{
printf("Can't open file for writing");
return;
}
//if you need to handle files > 2GB,
//be sure to use a 64bit integer, and
//a network-to-host function that can
//handle 64bit integers...
long size = 0;
if (read_all(sock, &size, sizeof(size)) == 1)
{
size = ntohl(size);
while (size > 0)
{
rval = read_all(sock, buf, min(sizeof(buf), size));
if (rval < 1)
break;
if (write_all(file, buf, rval) == -1)
break;
} 
}
fclose(file); 
} 

OriginalL'auteur Remy Lebeau