-/* 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"
+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)
+{
+ 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 *));
+ }
+
+ server->clients [server->num_clients - 1] = client;
+
+ pthread_mutex_unlock (&server->mutex);
+
+ return client;
+}
+
static void
-ttt_dispatch (int connected_socket)
+ttt_server_destroy_client (ttt_server_t *server, ttt_client_t *client)
{
-#define BUF_SIZE 1024
+ int i;
+
+ pthread_mutex_lock (&server->mutex);
+
+ 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);
+
+ 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;
while (1) {
- char buf[BUF_SIZE];
- int cnt;
- cnt = read (connected_socket, buf, BUF_SIZE);
- if (cnt == 0)
+
+ request = ttt_client_read_line (client);
+ if (request == NULL)
break;
- write (0, buf, cnt);
- write (connected_socket, buf, cnt);
+
+ ttt_server_broadcast (client->server, request);
}
+
+ ttt_server_destroy_client (server, client);
+
+ return (void *) 0;
+}
+
+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 TCP/IP server that handles one client at a time. The server is\n"
-"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. The server handles only one client at a time, but multiple clients\n"
-"may be able to connect simultaneously. Subsequent clients will see no\n"
-"output from the server until all previous clients exit.\n"
-"\nExtending the server to fork a new process for each client would be a fun\n"
-"project for a motivated 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;
+ ttt_server_t server;
int socket;
ttt_args_parse (&args, argc, argv);
printf (WELCOME_MESSAGE, args.host, args.port, args.host, args.port);
+ ttt_server_init (&server);
+
while (1)
- ttt_socket_accept (socket, ttt_dispatch);
+ ttt_socket_accept (socket, _accept_client, &server);
/* We only reach here if something bad happened. */
return 1;