X-Git-Url: https://git.cworth.org/git?p=ttt;a=blobdiff_plain;f=src%2Fttt-server.c;h=7a3ed341236658a9f34a7cd0651cff0cf03936ce;hp=2bc3a529b51efca60af87679488e248facd84b46;hb=3fb29eb6a3418db7048b27cece3b3fa96fbd69ce;hpb=15672ac8305a1c5ba0d9bf6edabb0a194c30628e

diff --git a/src/ttt-server.c b/src/ttt-server.c
index 2bc3a52..7a3ed34 100644
--- a/src/ttt-server.c
+++ b/src/ttt-server.c
@@ -19,15 +19,18 @@
  * Author: Carl Worth <cworth@cworth.org>
  */
 
-#include "ttt.h"
+#include "ttt-server.h"
+
 #include "ttt-args.h"
 #include "ttt-client.h"
+#include "ttt-error.h"
 #include "ttt-socket.h"
 
 struct _ttt_server {
     pthread_mutex_t mutex;
 
-    int next_client_id;
+    const char *host;
+    const char *port;
 
     ttt_client_t **clients;
     int clients_size;
@@ -35,28 +38,43 @@ struct _ttt_server {
 };
 
 static void
-ttt_server_init (ttt_server_t *server)
+ttt_server_init (ttt_server_t *server, const char *host, const char *port)
 {
     pthread_mutex_init (&server->mutex, NULL);
 
-    server->next_client_id = 0;
+    server->host = host;
+    server->port = port;
 
     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)
+/* Exported: See ttt-server.h for documentation. */
+ttt_error_t
+ttt_server_register_client (ttt_server_t *server, ttt_client_t *client)
 {
-    ttt_client_t *client;
+    int i;
+    ttt_error_t error = TTT_ERROR_NONE;
+    const char *username;
 
     pthread_mutex_lock (&server->mutex);
 
-    client = ttt_client_create (server, client_socket,
-				server->next_client_id++);
+    username = ttt_client_get_username (client);
+
+    assert (username != NULL);
 
-    printf ("Client %d has joined.\n", client->id);
+    if (username[0] == '\0')
+	return TTT_ERROR_INVALID_NAME;
+
+    for (i = 0; i < server->num_clients; i++) {
+	if (strcmp (ttt_client_get_username (server->clients[i]), username) == 0) {
+	    error = TTT_ERROR_INVALID_NAME;
+	    goto CLEANUP_LOCK;
+	}
+    }
+
+    fprintf (stderr, "Client %s has joined.\r\n", username);
 
     server->num_clients++;
 
@@ -72,13 +90,15 @@ ttt_server_create_client (ttt_server_t *server, int client_socket)
 
     server->clients [server->num_clients - 1] = client;
 
+ CLEANUP_LOCK:
     pthread_mutex_unlock (&server->mutex);
 
-    return client;
+    return error;
 }
 
-static void
-ttt_server_destroy_client (ttt_server_t *server, ttt_client_t *client)
+/* Exported: See ttt-server.h for documentation. */
+void
+ttt_server_unregister_client (ttt_server_t *server, ttt_client_t *client)
 {
     int i;
 
@@ -90,91 +110,172 @@ ttt_server_destroy_client (ttt_server_t *server, ttt_client_t *client)
 
     assert (i < server->num_clients);
 
-    printf ("Client %d has left.\n", client->id);
+    printf ("Client %s has left.\r\n", ttt_client_get_username (client));
 
     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);
+}
+
+/* Exported: See ttt-server.h for documentation. */
+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 void *
-_handle_client_requests_thread (void *closure)
+/* Exported: See ttt-server.h for documentation. */
+const char*
+ttt_server_who (ttt_server_t *server)
 {
-    ttt_client_t *client = closure;
-    ttt_server_t *server = client->server;
-    char *request;
+    int i;
+    char *response;
 
-    while (1) {
+    pthread_mutex_lock (&server->mutex);
 
-	request = ttt_client_read_line (client);
-	if (request == NULL)
-	    break;
+    xasprintf (&response, "WHO");
 
-	ttt_server_broadcast (client->server, request);
-    }
+    for (i = 0; i < server->num_clients; i++)
+	xasprintf (&response, "%s %s",
+		   response,
+		   ttt_client_get_username (server->clients[i]));
 
-    ttt_server_destroy_client (server, client);
+    xasprintf (&response, "%s\r\n", response);
+
+    pthread_mutex_unlock (&server->mutex);
 
-    return (void *) 0;
+    return response;
 }
 
-static void
-_accept_client (void *closure, int client_socket)
+/* Exported: See ttt-server.h for documentation. */
+ttt_error_t
+ttt_server_statistics (ttt_server_t *server, const char *username, char **response)
 {
-    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);
+    ttt_bool_t usernamefound = FALSE;
+    const char *client_username;
+    int client_num_wins;
+    int i;
+
+    pthread_mutex_lock (&server->mutex);
+
+    for (i = 0; i < server->num_clients; i++) {
+	client_username = ttt_client_get_username (server->clients[i]);
+	if (strcasecmp (username, client_username) == 0) {
+	    usernamefound = TRUE;
+	    client_num_wins = ttt_client_get_num_wins (server->clients[i]);
+	    xasprintf (response, "STATISTICS %s \"\r\n"
+		       "TICTACTOE WINS %d\r\n\"\r\n",
+		       client_username,
+		       client_num_wins);
+	}
     }
+
+    pthread_mutex_unlock (&server->mutex);
+
+    if (!usernamefound)
+	return TTT_ERROR_NO_USER;
+
+    return TTT_ERROR_NONE;
 }
 
-void
-ttt_server_broadcast (ttt_server_t *server, const char *message)
+/* Exported: See ttt-server.h for documentation. */
+ttt_error_t
+ttt_server_verify_username (ttt_server_t *server, const char *username)
 {
+    ttt_bool_t usernamefound = FALSE;
+    const char *client_username;
     int i;
 
     pthread_mutex_lock (&server->mutex);
 
-    for (i = 0; i < server->num_clients; i++)
-	ttt_client_send (server->clients[i], message);
+    for (i = 0; i < server->num_clients; i++) {
+	client_username = ttt_client_get_username (server->clients[i]);
+	if (strcasecmp (username, client_username) == 0)
+	    usernamefound = TRUE;
+    }
 
     pthread_mutex_unlock (&server->mutex);
+
+    if (!usernamefound)
+	return TTT_ERROR_NO_USER;
+
+    return TTT_ERROR_NONE;
+}
+
+/* Exported: See ttt-server.h for documentation. */
+const char*
+ttt_server_get_host (ttt_server_t *server)
+{
+    return server->host;
+}
+
+/* Exported: See ttt-server.h for documentation. */
+const char*
+ttt_server_get_port (ttt_server_t *server)
+{
+    return server->port;
 }
 
 static const char *WELCOME_MESSAGE = 
-"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, 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 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. 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";
+"Welcome to ttt-server. The server is currently listening on:\r\n"
+"\r\n"
+"	%s:%s\r\n"
+"\r\n"
+"To test this, simply connect one or more clients to that host and port.\r\n"
+"For example:\r\n"
+"\r\n"
+"	telnet %s %s\r\n"
+"\r\n"
+"The TTTP (tic-tac-toe protocol) has been partially implemented.\r\n"
+"The following commands should work: HELO, HELP, MESSAGE, VERSION, QUIT, WHO.\r\n"
+"\r\n";
+
+static void
+_ttt_server_accept (void *closure, int client_socket)
+{
+    ttt_server_t *server = closure;
+
+    ttt_client_new (server, client_socket);
+}
+
+static void
+_detach_and_write_child_pid_to (const char *filename)
+{
+    pid_t pid;
+
+    /* Use the Unix double-fork trick to detach completely. See
+     * setsid(2) for some details as to why two forks are
+     * needed. */
+    pid = xfork ();
+    if (pid) {
+	/* First parent just exits */
+	exit (0);
+    }
+    
+    chdir ("/");
+    setsid ();
+    
+    pid = xfork ();
+    if (pid) {
+	/* Second parent exits after writing pid */
+	FILE *file = xfopen (filename, "w");
+	fprintf (file, "%d\n", pid);
+	fclose (file);
+	exit (0);
+    }
+    
+    /* Final, detached child returns. */
+}
 
 int 
 main (int argc, char **argv)
@@ -185,17 +286,62 @@ main (int argc, char **argv)
 
     ttt_args_parse (&args, argc, argv);
 
-    if (args.log_file)
-	xfreopen (args.log_file, "a", stderr);
+    if (args.log_file || args.detach) {
+	FILE *log_file;
+	/* In the detach case, we force redirection to a log file. */
+	if (args.log_file == NULL)
+	    args.log_file = "/var/log/ttt-server.log";
+	log_file = fopen (args.log_file, "a");
+	if (log_file == NULL) {
+	    printf ("Warning: Failed to open log file %s: %s.\n",
+		    args.log_file, strerror (errno));
+	    printf ("Logging will be disabled.\n");
+	    xdup2 (1, 2);
+	} else {
+	    xdup2 (fileno (log_file), 2);
+	}
+    }
+
+    if (args.detach)
+	_detach_and_write_child_pid_to (args.pid_file);
+
+    /* Now that we've setup logging and the pid file, drop any special
+     * permissions we might have if we were asked to do that. */
+    if (args.user) {
+	int ret;
+	struct passwd *pwd;
+	errno = 0;
+	pwd = getpwnam (args.user);
+	if (pwd == NULL) {
+	    fprintf (stderr, "Error: Failed to lookup uid for %s: %s. Aborting.\n",
+		     args.user,
+		     errno == 0 ? "User not found" : strerror (errno));
+	    exit (1);
+	}
+	ret = setuid (pwd->pw_uid);
+	if (ret == -1) {
+	    fprintf (stderr, "Error: Failed to setuid to %d (%s): %s. Aborting.\n",
+		     pwd->pw_uid, args.user, strerror (errno));
+	    exit (1);
+	}
+    }
 
     socket = ttt_socket_create_server (args.host, args.port);
 
-    printf (WELCOME_MESSAGE, args.host, args.port, args.host, args.port);
+    if (args.detach) {
+	printf ("Server started listening on %s:%s\n", args.host, args.port);
+	fprintf (stderr, "Server started listening on %s:%s\n", args.host, args.port);
+    } else {
+	printf (WELCOME_MESSAGE, args.host, args.port, args.host, args.port);
+    }
+
+    fclose (stdout);
+    fclose (stdin);
 
-    ttt_server_init (&server);
+    ttt_server_init (&server, args.host, args.port);
 
     while (1)
-	ttt_socket_accept (socket, _accept_client, &server);
+	ttt_socket_accept (socket, _ttt_server_accept, &server);
 
     /* We only reach here if something bad happened. */
     return 1;