Start the first client with a special socketpair so it is already known to the

server rather than playing silly games to get them synchronised before doing
anything.

Change attach-session to start the server.

CHANGES

@@ -1,3 +1,9 @@
+19 January 2009
+
+* attach-session now tries to start the server if it isn't already started - if
+  no sessions are created in .tmux.conf this will cause an error.
+* Clean up starting server by making initial client get a special socketpair.
+
 18 January 2009
 
 * Unbreak UTF-8.
@@ -958,7 +964,7 @@
   (including mutt, emacs). No status bar yet and no key remapping or other
   customisation.
 
-$Id: CHANGES,v 1.220 2009-01-18 21:46:30 nicm Exp $
+$Id: CHANGES,v 1.221 2009-01-19 17:16:09 nicm Exp $
 
  LocalWords:  showw utf UTF fulvio ciriaco joshe OSC APC gettime abc DEF OA clr
  LocalWords:  rivo nurges lscm Erdely eol smysession mysession ek dstname RB ms

client.c

@@ -1,4 +1,4 @@
-/* $Id: client.c,v 1.40 2009-01-18 12:09:42 nicm Exp $ */
+/* $Id: client.c,v 1.41 2009-01-19 17:16:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -44,23 +44,20 @@ client_init(
 	struct winsize			ws;
 	size_t				size;
 	int				mode;
-	u_int				retries;
 	struct buffer		       *b;
 	char			       *name;
 
-	retries = 0;
-retry:
 	if (stat(path, &sb) != 0) {
 		if (start_server && errno == ENOENT) {
-			if (server_start(path) != 0)
-				goto no_start;
-			goto retry;
+			if ((cctx->srv_fd = server_start(path)) == -1)
+				goto start_failed;
+			goto server_started;
 		}
-		goto fail;
+		goto not_found;
 	}
 	if (!S_ISSOCK(sb.st_mode)) {
 		errno = ENOTSOCK;
-		goto fail;
+		goto not_found;
 	}
 
 	memset(&sa, 0, sizeof sa);
@@ -68,7 +65,7 @@ retry:
 	size = strlcpy(sa.sun_path, path, sizeof sa.sun_path);
 	if (size >= sizeof sa.sun_path) {
 		errno = ENAMETOOLONG;
-		goto fail;
+		goto not_found;
 	}
 
 	if ((cctx->srv_fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
@@ -76,16 +73,17 @@ retry:
 
 	if (connect(
 	    cctx->srv_fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) == -1) {
-		if (start_server && errno == ECONNREFUSED && retries < 10) {
-			if (unlink(path) != 0)
-				goto fail;
-			if (server_start(path) != 0)
-				goto no_start;
+		if (errno == ECONNREFUSED) {
+			if (unlink(path) != 0 || !start_server)
+				goto not_found;
+			if ((cctx->srv_fd = server_start(path)) == -1)
+				goto start_failed;
+			goto server_started;
 		}
-		retries++;
-		goto retry;
+		goto not_found;
 	}
 
+server_started:
 	if ((mode = fcntl(cctx->srv_fd, F_GETFL)) == -1)
 		fatal("fcntl");
 	if (fcntl(cctx->srv_fd, F_SETFL, mode|O_NONBLOCK) == -1)
@@ -118,11 +116,11 @@ retry:
 
 	return (0);
 
-no_start:
+start_failed:
 	log_warnx("server failed to start");
 	return (1);
 
-fail:
+not_found:
 	log_warn("server not found");
 	return (1);
 }

cmd-attach-session.c

@@ -1,4 +1,4 @@
-/* $Id: cmd-attach-session.c,v 1.21 2008-12-10 20:25:41 nicm Exp $ */
+/* $Id: cmd-attach-session.c,v 1.22 2009-01-19 17:16:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -29,7 +29,7 @@ void	cmd_attach_session_exec(struct cmd *, struct cmd_ctx *);
 const struct cmd_entry cmd_attach_session_entry = {
 	"attach-session", "attach",
 	"[-d] " CMD_TARGET_SESSION_USAGE,
-	CMD_DFLAG|CMD_CANTNEST,
+       	CMD_DFLAG|CMD_CANTNEST|CMD_STARTSERVER,
 	cmd_target_init,
 	cmd_target_parse,
 	cmd_attach_session_exec,
@@ -45,10 +45,14 @@ cmd_attach_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 	struct cmd_target_data	*data = self->data;
 	struct session		*s;
 	char			*cause;
-
+	
 	if (ctx->curclient != NULL)
 		return;
 
+	if (ARRAY_LENGTH(&sessions) == 0) {
+		ctx->error(ctx, "no sessions");
+		return;
+	}
 	if ((s = cmd_find_session(ctx, data->target)) == NULL)
 		return;
 

server.c

@@ -1,4 +1,4 @@
-/* $Id: server.c,v 1.108 2009-01-18 14:40:48 nicm Exp $ */
+/* $Id: server.c,v 1.109 2009-01-19 17:16:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -58,6 +58,51 @@ void		 server_check_timers(struct client *);
 void		 server_second_timers(void);
 int		 server_update_socket(const char *);
 
+/* Create a new client. */
+struct client *
+server_create_client(int fd)
+{
+	struct client	*c;
+	int		 mode;
+	u_int		 i;
+
+	if ((mode = fcntl(fd, F_GETFL)) == -1)
+		fatal("fcntl failed");
+	if (fcntl(fd, F_SETFL, mode|O_NONBLOCK) == -1)
+		fatal("fcntl failed");
+
+	c = xcalloc(1, sizeof *c);
+	c->fd = fd;
+	c->in = buffer_create(BUFSIZ);
+	c->out = buffer_create(BUFSIZ);
+
+	ARRAY_INIT(&c->prompt_hdata);
+
+	c->tty.fd = -1;
+	c->title = NULL;
+
+	c->session = NULL;
+	c->sx = 80;
+	c->sy = 25;
+	screen_init(&c->status, c->sx, 1, 0);
+
+	c->message_string = NULL;
+
+	c->prompt_string = NULL;
+	c->prompt_buffer = NULL;
+	c->prompt_index = 0;
+
+	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
+		if (ARRAY_ITEM(&clients, i) == NULL) {
+			ARRAY_SET(&clients, i, c);
+			return (c);
+		}
+	}
+	ARRAY_ADD(&clients, c);
+	return (c);
+}
+
+/* Find client index. */
 int
 server_client_index(struct client *c)
 {
@@ -79,9 +124,8 @@ server_start(const char *path)
 	mode_t			mask;
 	int		   	n, fd, pair[2], mode;
 	char		       *cause;
-	u_char			ch;
 
-	/* Make a little socketpair to wait for the server to be ready. */
+	/* The first client is special and gets a socketpair; create it. */
 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pair) != 0)
 		fatal("socketpair failed");
 
@@ -92,17 +136,7 @@ server_start(const char *path)
 		break;
 	default:
 		close(pair[1]);
-
-		ch = 0x00;
-		if (read(pair[0], &ch, 1) == 1 && ch == 0xff) {
-			close(pair[0]);
-			return (0);
-		}
-		ch = 0x00;
-		if (write(pair[1], &ch, 1) != 1)
-			fatal("write failed");
-		close(pair[0]);
-		return (1);
+		return (pair[0]);
 	}
 	close(pair[0]);
 
@@ -166,11 +200,7 @@ server_start(const char *path)
 	if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1)
 		fatal("fcntl failed");
 
-	ch = 0xff;
-	if (write(pair[1], &ch, 1) != 1)
-		fatal("write failed");
-	read(pair[1], &ch, 1); /* Ignore errors; just to wait before closing. */
-	close(pair[1]);
+	server_create_client(pair[1]);
 
 	n = server_main(path, fd);
 #ifdef DEBUG
@@ -532,52 +562,17 @@ server_handle_clients(struct pollfd **pfd)
 struct client *
 server_accept_client(int srv_fd)
 {
-	struct client	       *c;
 	struct sockaddr_storage	sa;
 	socklen_t		slen = sizeof sa;
-	int		 	client_fd, mode;
-	u_int			i;
+	int			fd;
 
-	client_fd = accept(srv_fd, (struct sockaddr *) &sa, &slen);
-	if (client_fd == -1) {
+	fd = accept(srv_fd, (struct sockaddr *) &sa, &slen);
+	if (fd == -1) {
 		if (errno == EAGAIN || errno == EINTR || errno == ECONNABORTED)
 			return (NULL);
 		fatal("accept failed");
 	}
-	if ((mode = fcntl(client_fd, F_GETFL)) == -1)
-		fatal("fcntl failed");
-	if (fcntl(client_fd, F_SETFL, mode|O_NONBLOCK) == -1)
-		fatal("fcntl failed");
-
-	c = xcalloc(1, sizeof *c);
-	c->fd = client_fd;
-	c->in = buffer_create(BUFSIZ);
-	c->out = buffer_create(BUFSIZ);
-
-	ARRAY_INIT(&c->prompt_hdata);
-
-	c->tty.fd = -1;
-	c->title = NULL;
-
-	c->session = NULL;
-	c->sx = 80;
-	c->sy = 25;
-	screen_init(&c->status, c->sx, 1, 0);
-
-	c->message_string = NULL;
-
-	c->prompt_string = NULL;
-	c->prompt_buffer = NULL;
-	c->prompt_index = 0;
-
-	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
-		if (ARRAY_ITEM(&clients, i) == NULL) {
-			ARRAY_SET(&clients, i, c);
-			return (c);
-		}
-	}
-	ARRAY_ADD(&clients, c);
-	return (c);
+	return (server_create_client(fd));
 }
 
 /* Input data from client. */

tmux.1

@@ -1,4 +1,4 @@
-.\" $Id: tmux.1,v 1.66 2009-01-17 17:16:31 nicm Exp $
+.\" $Id: tmux.1,v 1.67 2009-01-19 17:16:09 nicm Exp $
 .\"
 .\" Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
 .\"
@@ -345,6 +345,11 @@ Create a new client in the current terminal and attach it to a session.
 If
 .Fl d
 is specified, any other clients attached to the session are detached.
+.Pp
+If no server is started,
+.It attach-session
+will attempt to start it; this will fail unless sessions are created in the
+configuration file.
 .It Xo Ic bind-key
 .Ar key Ar command Op Ar arguments
 .Xc

tmux.h

@@ -1,4 +1,4 @@
-/* $Id: tmux.h,v 1.241 2009-01-18 21:46:30 nicm Exp $ */
+/* $Id: tmux.h,v 1.242 2009-01-19 17:16:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -1253,6 +1253,7 @@ const char *key_string_lookup_key(int);
 
 /* server.c */
 extern struct clients clients;
+struct client *server_create_client(int);
 int	 server_client_index(struct client *);
 int	 server_start(const char *);