X-Git-Url: https://git.cworth.org/git?p=ttt;a=blobdiff_plain;f=src%2Fttt-server.c;h=7a3ed341236658a9f34a7cd0651cff0cf03936ce;hp=316a27021ec6919a7985e80df95fafde2c3b5fc3;hb=3fb29eb6a3418db7048b27cece3b3fa96fbd69ce;hpb=5d56d3cd8b4685e905ed604277ac9cb32c876127 diff --git a/src/ttt-server.c b/src/ttt-server.c index 316a270..7a3ed34 100644 --- a/src/ttt-server.c +++ b/src/ttt-server.c @@ -19,71 +19,263 @@ * Author: Carl Worth */ -#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; + const char *host; + const char *port; + ttt_client_t **clients; + int clients_size; int num_clients; }; 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->host = host; + server->port = port; + server->clients = NULL; + server->clients_size = 0; server->num_clients = 0; } -static void -ttt_server_add_client (ttt_server_t *server, ttt_client_t *client) +/* Exported: See ttt-server.h for documentation. */ +ttt_error_t +ttt_server_register_client (ttt_server_t *server, ttt_client_t *client) { + int i; + ttt_error_t error = TTT_ERROR_NONE; + const char *username; + pthread_mutex_lock (&server->mutex); + username = ttt_client_get_username (client); + + assert (username != NULL); + + 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++; - server->clients = xrealloc (server->clients, - server->num_clients * sizeof (ttt_client_t *)); + + 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; + CLEANUP_LOCK: pthread_mutex_unlock (&server->mutex); + + return error; } -static void -_accept_client (void *closure, int client_socket) +/* Exported: See ttt-server.h for documentation. */ +void +ttt_server_unregister_client (ttt_server_t *server, ttt_client_t *client) { - ttt_server_t *server = closure; - ttt_client_t *client; - - client = ttt_client_create (server, client_socket); + 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 %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 *)); - ttt_server_add_client (server, client); + server->num_clients--; - ttt_client_handle_requests (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); +} + +/* Exported: See ttt-server.h for documentation. */ +const char* +ttt_server_who (ttt_server_t *server) +{ + int i; + char *response; + + pthread_mutex_lock (&server->mutex); + + xasprintf (&response, "WHO"); + + for (i = 0; i < server->num_clients; i++) + xasprintf (&response, "%s %s", + response, + ttt_client_get_username (server->clients[i])); + + xasprintf (&response, "%s\r\n", response); + + pthread_mutex_unlock (&server->mutex); + + return response; +} + +/* Exported: See ttt-server.h for documentation. */ +ttt_error_t +ttt_server_statistics (ttt_server_t *server, const char *username, char **response) +{ + 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; +} + +/* 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++) { + 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 simply a demonstration\n" -"of a TCP/IP server capable of handling multiple simultaneous clients.\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" -"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" -"\nNote that to terminate the telnet client you type Control-], then\n" -", then \"close\" (and ) at the \"telnet> \" prompt.\n" -"\nHave fun!\n" -"-Carl\n" -"\nPS. The server does support multiple clients, but there is not yet any\n" -"interaction between the clients. The next step is probably to turn the\n" -"server into a simple chat server. After that, we should have the necessary\n" -"structure in place to start implementing the real tic-tac-toe protocol.\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) @@ -94,17 +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;