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|
#ifdef __cplusplus
#error Be sure you are using a C compiler...
#endif
#if defined (WIN32) || defined (_WIN32)
#include <winsock2.h>
#elif defined (linux) || defined (_POSIX_VERSION) || defined (_POSIX2_C_VERSION)\
|| defined (_XOPEN_VERSION)
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h> /* close */
#define INVALID_SOCKET -1
#define SOCKET_ERROR -1
#define closesocket(s) close (s)
typedef int SOCKET;
typedef struct sockaddr_in SOCKADDR_IN;
typedef struct sockaddr SOCKADDR;
#else
#error not defined for this platform
#endif
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
/* macros ============================================================== */
/* we want to listen to the 5000 port */
#define PORT 5000
#define ESC 27
/* constants =========================================================== */
/* types =============================================================== */
/* structures ========================================================== */
struct cli
{
pthread_t thread;
SOCKADDR_IN sin;
int recsize;
SOCKET sock;
int err;
};
/* private data ======================================================== */
/* private functions =================================================== */
/* thread client function */
static void *client (void *p_data)
{
struct cli *p_cli = p_data;
if (p_cli != NULL)
{
int end = 0;
do
{
/* wait for the receive of a data block */
unsigned char data[128];
int sock_err = recv (p_cli->sock, data, (sizeof data - 1), 0);
if (sock_err != SOCKET_ERROR)
{
size_t nb_rec = sock_err;
if (nb_rec > 0)
{
/* convert to string */
data[nb_rec] = 0;
printf ("%u byte%s received:\n'%s'\n",
(unsigned) nb_rec, nb_rec > 1 ? "s" : "", data);
fflush (stdout);
if (data[0] == ESC)
{
end = 1;
}
else
{
/* send some YES-TO-ALL answer */
char const response[] = "OK\n";
send (p_cli->sock, response, strlen (response), 0);
}
}
else
{
puts ("client is disconnected");
end = 1;
}
}
else
{
perror ("socket.recv");
p_cli->err = 1;
end = 1;
}
}
while (!end);
shutdown (p_cli->sock, 2);
printf ("closing client socket %d...\n", p_cli->sock);
closesocket (p_cli->sock), p_cli->sock = INVALID_SOCKET;
/* the memory is now under the control of the thread */
free (p_cli), p_cli = NULL;
}
return NULL;
}
static int clients (SOCKET sock)
{
int err = 0;
int end = 0;
do
{
/* wait for a client connection */
printf ("waiting for a client connection on port %d...\n", PORT);
{
/* create a new client context */
struct cli *p_cli = malloc (sizeof *p_cli);
if (p_cli != NULL)
{
p_cli->recsize = (int) sizeof p_cli->sin;
p_cli->sock =
accept (sock, (SOCKADDR *) &p_cli->sin, &p_cli->recsize);
if (p_cli->sock != INVALID_SOCKET)
{
printf
("client connected with socket %d from %s:%d\n",
p_cli->sock, inet_ntoa (p_cli->sin.sin_addr),
htons (p_cli->sin.sin_port));
/* send ...*/
pthread_create (&p_cli->thread, NULL, client, p_cli);
/* ... and forget */
p_cli = NULL;
}
else
{
perror ("socket.accept");
err = 1;
}
}
else
{
fprintf (stderr, "client creation failed : memory error\n");
}
}
}
while (!end);
return err;
}
/* ---------------------------------------------------------------------
--------------------------------------------------------------------- */
static int app (void)
{
int err = 0;
/* open a socket in TCP/IP mode. */
SOCKET sock = socket (AF_INET, SOCK_STREAM, 0);
if (sock != INVALID_SOCKET)
{
printf ("socket %d is now opened in TCP/IP mode\n", sock);
/* we want to listen on the TELNET port */
{
int sock_err;
/* assign the listening port */
SOCKADDR_IN sin = { 0 };
/* automatic IP address */
sin.sin_addr.s_addr = htonl (INADDR_ANY);
/* protocol family (IP) */
sin.sin_family = AF_INET;
/* listening port */
sin.sin_port = htons (PORT);
/* bind */
sock_err = bind (sock, (SOCKADDR *) &sin, sizeof sin);
if (sock_err != SOCKET_ERROR)
{
/* start listening (server mode) */
sock_err = listen (sock, 5);
printf ("listening on port %d...\n", PORT);
if (sock_err != SOCKET_ERROR)
{
err = clients (sock);
}
else
{
perror ("socket.listen");
err = 1;
}
}
else
{
perror ("socket.bind");
err = 1;
}
printf ("closing socket %d...\n", sock);
/* close the socket. */
sock_err = closesocket (sock), sock = INVALID_SOCKET;
printf ("the socket is now closed\n");
if (sock_err)
{
perror ("socket.close");
err = 1;
}
}
}
else
{
perror ("socket.open");
err = 1;
}
return err;
}
/* entry point ========================================================= */
/* ---------------------------------------------------------------------
--------------------------------------------------------------------- */
int main (void)
{
int ret;
#if defined (WIN32) || defined (_WIN32)
WSADATA wsa_data;
int err = WSAStartup (MAKEWORD (2, 2), &wsa_data);
if (!err)
{
puts ("WIN: winsock2: OK");
#else
int err = 0;
{
#endif
err = app ();
#if defined (WIN32) || defined (_WIN32)
WSACleanup ();
#else
}
#endif
if (err)
{
ret = EXIT_FAILURE;
}
else
{
ret = EXIT_SUCCESS;
}
system ("pause");
return ret;
} |
