-/* ttt.c - client-server tic-tac-toe game
+/* ttt-server.c - tic-tac-toe game server
*
* Copyright © 2005 Carl Worth
*
*/
#include "ttt.h"
+#include "ttt-args.h"
+#include "ttt-client.h"
+#include "ttt-socket.h"
-static ttt_status_t
-_sockaddr_init (struct sockaddr_in *addr,
- const char *host,
- const char *port)
+struct _ttt_server {
+ pthread_mutex_t mutex;
+
+ int next_client_id;
+
+ ttt_client_t **clients;
+ int clients_size;
+ int num_clients;
+};
+
+static void
+ttt_server_init (ttt_server_t *server)
{
- struct hostent *hostent;
- struct servent *servent;
- char *endptr;
- long port_long;
- uint16_t port_short;
-
- addr->sin_family = AF_INET;
-
- hostent = gethostbyname (host);
- if (hostent == NULL)
- {
- fprintf (stderr, "Error: Lookup failed for host %s: %s\n",
- host, hstrerror (h_errno));
- return TTT_STATUS_FAILURE;
- }
- memcpy (&addr->sin_addr.s_addr, hostent->h_addr_list[0],
- sizeof (addr->sin_addr.s_addr));
-
- assert (*port != '\0');
- port_long = strtol (port, &endptr, 10);
- if (*endptr == '\0')
- {
- /* Numeric port*/
- if (port_long <= 0 || port_long >= (1 << 16)) {
- fprintf (stderr, "Error: Port %ld out of range.\n", port_long);
- return TTT_STATUS_FAILURE;
- }
- port_short = port_long;
- addr->sin_port = htons (port_short);
- } else {
- /* Named port */
- servent = getservbyname (port, "tcp");
- if (port == NULL) {
- fprintf (stderr, "Error: Lookup failed for port %s: %s\n",
- port, hstrerror (h_errno));
- return TTT_STATUS_FAILURE;
- }
- addr->sin_port = servent->s_port;
+ pthread_mutex_init (&server->mutex, NULL);
+
+ server->next_client_id = 0;
+
+ server->clients = NULL;
+ server->clients_size = 0;
+ server->num_clients = 0;
+}
+
+static ttt_client_t *
+ttt_server_create_client (ttt_server_t *server, int client_socket)
+{
+ ttt_client_t *client;
+
+ pthread_mutex_lock (&server->mutex);
+
+ client = ttt_client_create (server, client_socket,
+ server->next_client_id++);
+
+ printf ("Client %d has joined.\n", client->id);
+
+ server->num_clients++;
+
+ if (server->num_clients > server->clients_size) {
+ if (server->clients_size == 0)
+ server->clients_size = 1;
+ else
+ server->clients_size *= 2;
+
+ server->clients = xrealloc (server->clients,
+ server->clients_size * sizeof (ttt_client_t *));
}
- return TTT_STATUS_SUCCESS;
+ server->clients [server->num_clients - 1] = client;
+
+ pthread_mutex_unlock (&server->mutex);
+
+ return client;
}
-static int
-_wait_for_connection (int listen_socket)
+static void
+ttt_server_destroy_client (ttt_server_t *server, ttt_client_t *client)
{
- fd_set read_set;
- int num_selected;
- int flags, err;
- int connected_socket;
+ int i;
- FD_ZERO (&read_set);
- FD_SET (listen_socket, &read_set);
+ pthread_mutex_lock (&server->mutex);
- while (1) {
- num_selected = select (listen_socket + 1,
- &read_set, NULL, NULL,
- NULL);
+ for (i = 0; i < server->num_clients; i++)
+ if (server->clients[i] == client)
+ break;
+
+ assert (i < server->num_clients);
+
+ printf ("Client %d has left.\n", client->id);
+
+ memmove (&server->clients[i], &server->clients[i+1],
+ (server->num_clients - i - 1) * sizeof (ttt_client_t *));
+
+ server->num_clients--;
+
+ ttt_client_destroy (client);
- flags = fcntl (listen_socket, F_GETFL);
- flags |= O_NONBLOCK;
- xfcntl (listen_socket, F_SETFL, flags);
+ pthread_mutex_unlock (&server->mutex);
+}
+
+static void *
+_handle_client_requests_thread (void *closure)
+{
+ ttt_client_t *client = closure;
+ ttt_server_t *server = client->server;
+ char *request;
- connected_socket = accept (listen_socket, 0, 0);
- err = errno;
+ while (1) {
+
+ request = ttt_client_read_line (client);
+ if (request == NULL)
+ break;
- flags &= ~O_NONBLOCK;
- xfcntl (listen_socket, F_SETFL, flags);
+ ttt_server_broadcast (client->server, request);
+ }
- if (connected_socket != -1)
- return connected_socket;
+ ttt_server_destroy_client (server, client);
- if (err == EWOULDBLOCK || err == EAGAIN)
- continue;
+ return (void *) 0;
+}
- fprintf (stderr, "Error: accept failed: %s. Aborting.\n",
+static void
+_accept_client (void *closure, int client_socket)
+{
+ ttt_server_t *server = closure;
+ ttt_client_t *client;
+ int err;
+
+ client = ttt_server_create_client (server, client_socket);
+
+ err = pthread_create (&client->thread, NULL,
+ _handle_client_requests_thread, client);
+ if (err != 0) {
+ fprintf (stderr, "Error: pthread_create failed: %s. Aborting.\n",
strerror (err));
exit (1);
}
}
+void
+ttt_server_broadcast (ttt_server_t *server, const char *message)
+{
+ int i;
+
+ pthread_mutex_lock (&server->mutex);
+
+ for (i = 0; i < server->num_clients; i++)
+ ttt_client_send (server->clients[i], message);
+
+ pthread_mutex_unlock (&server->mutex);
+}
+
static const char *WELCOME_MESSAGE =
-"Welcome to ttt-server. So far, this program is simply a demonstration\n"
-"of a one-shot TCP/IP server. The server is currently listening on:\n"
+"Welcome to ttt-server. So far, this program is still a demonstration\n"
+"TCP/IP server, acting something like a rather braindead chat server.\n"
+"The server is currently listening on:\n"
"\n %s:%s\n"
-"\nTo test this program, simply connect a client to that host and port.\n"
+"\nTo test this, simply connect one or more clients to that host and port.\n"
"For example:\n"
"\n telnet %s %s\n"
-"\nOnce you have connected a client, the server will echo any characters\n"
-"it receives back to the client as well as to stdout.\n"
+"\nOnce you have connected a client, the server will send each line of text\n"
+"it receives to all connected clients. The server reports client joins and\n"
+"departures on stdout.\n"
"\nNote that to terminate the telnet client you type Control-], then\n"
"<Enter>, then \"close\" (and <Enter>) at the \"telnet> \" prompt.\n"
"\nHave fun!\n"
"-Carl\n"
-"\nPS. By one-shot, I mean that the server will only accept a connection\n"
-"from a single client, and the server will exit when that client disconnects\n"
-"To test the server again, you will need to manually restart it again.\n"
-"Extending the server to start listening again, or to handle multiple\n"
-"clients simultaneously would both be fun projects for a motivated\n"
-"student (as would writing a custom client program).\n\n";
+"\nPS. At this point we're ready to leave the demonstration phase and to\n"
+"begin implementing TTTP (tic-tac-toe protocol) as well as fixing the\n"
+"protocol specifcation. We don't need a custom client to move forward on\n"
+"the server (that is one of the ideas behind using a telnet-compatible\n"
+"protocol), but a custom client would still be a fine project for a\n"
+"motivated beginning programmer.\n\n";
int
main (int argc, char **argv)
{
ttt_args_t args;
- int args_first;
- int listen_socket, connected_socket;
- struct sockaddr_in addr;
-
- ttt_args_parse (&args, argc, argv, &args_first);
-
- listen_socket = xsocket (PF_INET, SOCK_STREAM, 0);
-
-#define HOST "localhost"
-#define PORT "5534"
+ ttt_server_t server;
+ int socket;
- _sockaddr_init (&addr, HOST, PORT);
+ ttt_args_parse (&args, argc, argv);
-#ifdef SO_REUSEADDR
- {
- int one = 1;
- setsockopt (listen_socket, SOL_SOCKET,
- SO_REUSEADDR, (char *) &one, sizeof (int));
- }
-#endif
-
- xbind (listen_socket, (struct sockaddr *) &addr, sizeof (addr));
-
- xlisten (listen_socket, SOMAXCONN);
+ if (args.log_file)
+ xfreopen (args.log_file, "a", stderr);
- printf (WELCOME_MESSAGE, HOST, PORT, HOST, PORT);
+ socket = ttt_socket_create_server (args.host, args.port);
- connected_socket = _wait_for_connection (listen_socket);
+ printf (WELCOME_MESSAGE, args.host, args.port, args.host, args.port);
-#define BUF_SIZE 1024
+ ttt_server_init (&server);
- while (1) {
- char buf[BUF_SIZE];
- int cnt;
- cnt = read (connected_socket, buf, BUF_SIZE);
- if (cnt == 0)
- break;
- write (0, buf, cnt);
- write (connected_socket, buf, cnt);
- }
+ while (1)
+ ttt_socket_accept (socket, _accept_client, &server);
- return 0;
+ /* We only reach here if something bad happened. */
+ return 1;
}
projects / ttt / blobdiff