Merge branch 'obsd-master'

Conflicts:
	Makefile
	client.c
	server-client.c
	server.c
	tmux.c
	tmux.h

43 files changed, 860 insertions, 812 deletions

diff --git a/Makefile.am b/Makefile.am
index 8b39ccfc..9cf3bc87 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -154,6 +154,7 @@ dist_tmux_SOURCES = \
 	options-table.c \
 	options.c \
 	paste.c \
+	proc.c \
 	resize.c \
 	screen-redraw.c \
 	screen-write.c \
diff --git a/alerts.c b/alerts.c
index 806e565b..f1477030 100644
--- a/alerts.c
+++ b/alerts.c
@@ -80,11 +80,11 @@ alerts_enabled(struct window *w, int flags)
 	struct session	*s;
 
 	if (flags & WINDOW_ACTIVITY) {
-		if (options_get_number(&w->options, "monitor-activity"))
+		if (options_get_number(w->options, "monitor-activity"))
 			return (1);
 	}
 	if (flags & WINDOW_SILENCE) {
-		if (options_get_number(&w->options, "monitor-silence") != 0)
+		if (options_get_number(w->options, "monitor-silence") != 0)
 			return (1);
 	}
 	if (~flags & WINDOW_BELL)
@@ -92,7 +92,7 @@ alerts_enabled(struct window *w, int flags)
 	RB_FOREACH(s, sessions, &sessions) {
 		if (!session_has(s, w))
 			continue;
-		if (options_get_number(&s->options, "bell-action") != BELL_NONE)
+		if (options_get_number(s->options, "bell-action") != BELL_NONE)
 			return (1);
 	}
 	return (0);
@@ -116,7 +116,7 @@ alerts_reset(struct window *w)
 	event_del(&w->alerts_timer);
 
 	timerclear(&tv);
-	tv.tv_sec = options_get_number(&w->options, "monitor-silence");
+	tv.tv_sec = options_get_number(w->options, "monitor-silence");
 
 	log_debug("@%u alerts timer reset %u", w->id, (u_int)tv.tv_sec);
 	if (tv.tv_sec != 0)
@@ -160,11 +160,11 @@ alerts_check_bell(struct session *s, struct winlink *wl)
 	if (s->curw->window == w)
 		w->flags &= ~WINDOW_BELL;
 
-	action = options_get_number(&s->options, "bell-action");
+	action = options_get_number(s->options, "bell-action");
 	if (action == BELL_NONE)
 		return (0);
 
-	visual = options_get_number(&s->options, "visual-bell");
+	visual = options_get_number(s->options, "visual-bell");
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (c->session != s || c->flags & CLIENT_CONTROL)
 			continue;
@@ -201,14 +201,14 @@ alerts_check_activity(struct session *s, struct winlink *wl)
 	if (s->curw == wl && !(s->flags & SESSION_UNATTACHED))
 		return (0);
 
-	if (!options_get_number(&w->options, "monitor-activity"))
+	if (!options_get_number(w->options, "monitor-activity"))
 		return (0);
 
-	if (options_get_number(&s->options, "bell-on-alert"))
+	if (options_get_number(s->options, "bell-on-alert"))
 		alerts_ring_bell(s);
 	wl->flags |= WINLINK_ACTIVITY;
 
-	if (options_get_number(&s->options, "visual-activity")) {
+	if (options_get_number(s->options, "visual-activity")) {
 		TAILQ_FOREACH(c, &clients, entry) {
 			if (c->session != s)
 				continue;
@@ -233,14 +233,14 @@ alerts_check_silence(struct session *s, struct winlink *wl)
 	if (s->curw == wl && !(s->flags & SESSION_UNATTACHED))
 		return (0);
 
-	if (options_get_number(&w->options, "monitor-silence") == 0)
+	if (options_get_number(w->options, "monitor-silence") == 0)
 		return (0);
 
-	if (options_get_number(&s->options, "bell-on-alert"))
+	if (options_get_number(s->options, "bell-on-alert"))
 		alerts_ring_bell(s);
 	wl->flags |= WINLINK_SILENCE;
 
-	if (options_get_number(&s->options, "visual-silence")) {
+	if (options_get_number(s->options, "visual-silence")) {
 		TAILQ_FOREACH(c, &clients, entry) {
 			if (c->session != s)
 				continue;
diff --git a/client.c b/client.c
index 6c9f0fcd..66bc0dab 100644
--- a/client.c
+++ b/client.c
@@ -33,10 +33,10 @@
 
 #include "tmux.h"
 
-int		client_flags;
-struct imsgbuf	client_ibuf;
-struct event	client_event;
-struct event	client_stdin;
+struct tmuxproc	*client_proc;
+struct tmuxpeer	*client_peer;
+int		 client_flags;
+struct event	 client_stdin;
 enum {
 	CLIENT_EXIT_NONE,
 	CLIENT_EXIT_DETACHED,
@@ -47,24 +47,21 @@ enum {
 	CLIENT_EXIT_EXITED,
 	CLIENT_EXIT_SERVER_EXITED,
 } client_exitreason = CLIENT_EXIT_NONE;
-int		client_exitval;
-enum msgtype	client_exittype;
-const char     *client_exitsession;
-int		client_attached;
+int		 client_exitval;
+enum msgtype	 client_exittype;
+const char	*client_exitsession;
+int		 client_attached;
 
 __dead void	client_exec(const char *);
 int		client_get_lock(char *);
 int		client_connect(struct event_base *, char *, int);
 void		client_send_identify(const char *, const char *);
-int		client_write_one(enum msgtype, int, const void *, size_t);
-int		client_write_server(enum msgtype, const void *, size_t);
-void		client_update_event(void);
-void		client_signal(int, short, void *);
 void		client_stdin_callback(int, short, void *);
 void		client_write(int, const char *, size_t);
-void		client_callback(int, short, void *);
-int		client_dispatch_attached(void);
-int		client_dispatch_wait(void);
+void		client_signal(int);
+void		client_dispatch(struct imsg *, void *);
+void		client_dispatch_attached(struct imsg *);
+void		client_dispatch_wait(struct imsg *);
 const char     *client_exit_message(void);
 
 /*
@@ -222,6 +219,9 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 	struct termios		 tio, saved_tio;
 	size_t			 size;
 
+	/* Ignore SIGCHLD now or daemon() in the server will leave a zombie. */
+	signal(SIGCHLD, SIG_IGN);
+
 	/* Save the flags. */
 	client_flags = flags;
 
@@ -254,9 +254,6 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		cmd_list_free(cmdlist);
 	}
 
-	/* Establish signal handlers. */
-	set_signals(client_signal);
-
 	/* Initialize the client socket and start the server. */
 	fd = client_connect(base, socket_path, cmdflags & CMD_STARTSERVER);
 	if (fd == -1) {
@@ -270,6 +267,10 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		return (1);
 	}
 
+	/* Build process state. */
+	client_proc = proc_start("client", base, 0, client_signal);
+	client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL);
+
 	/* Save these before pledge(). */
 	if ((cwd = getcwd(path, sizeof path)) == NULL)
 		cwd = "/";
@@ -291,21 +292,11 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 #endif
 
 	/* Free stuff that is not used in the client. */
-	options_free(&global_options);
-	options_free(&global_s_options);
-	options_free(&global_w_options);
+	options_free(global_options);
+	options_free(global_s_options);
+	options_free(global_w_options);
 	environ_free(&global_environ);
 
-	/* Set process title, log and signals now this is the client. */
-#ifdef HAVE_SETPROCTITLE
-	setproctitle("client (%s)", socket_path);
-#endif
-	logfile("client");
-
-	/* Create imsg. */
-	imsg_init(&client_ibuf, fd);
-	event_set(&client_event, fd, EV_READ, client_callback, NULL);
-
 	/* Create stdin handler. */
 	setblocking(STDIN_FILENO, 0);
 	event_set(&client_stdin, STDIN_FILENO, EV_READ|EV_PERSIST,
@@ -351,18 +342,17 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		size += sizeof *data;
 
 		/* Send the command. */
-		if (client_write_server(msg, data, size) != 0) {
+		if (proc_send(client_peer, msg, -1, data, size) != 0) {
 			fprintf(stderr, "failed to send command\n");
 			free(data);
 			return (1);
 		}
 		free(data);
 	} else if (msg == MSG_SHELL)
-		client_write_server(msg, NULL, 0);
+		proc_send(client_peer, msg, -1, NULL, 0);
 
-	/* Set the event and dispatch. */
-	client_update_event();
-	event_dispatch();
+	/* Start main loop. */
+	proc_loop(client_proc, NULL);
 
 	/* Print the exit message, if any, and exit. */
 	if (client_attached) {
@@ -394,144 +384,29 @@ client_send_identify(const char *ttynam, const char *cwd)
 	int		  fd, flags = client_flags;
 	pid_t		  pid;
 
-	client_write_one(MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags);
+	proc_send(client_peer, MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags);
 
 	if ((s = getenv("TERM")) == NULL)
 		s = "";
-	client_write_one(MSG_IDENTIFY_TERM, -1, s, strlen(s) + 1);
+	proc_send(client_peer, MSG_IDENTIFY_TERM, -1, s, strlen(s) + 1);
 
-	client_write_one(MSG_IDENTIFY_TTYNAME, -1, ttynam, strlen(ttynam) + 1);
-	client_write_one(MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1);
+	proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam, strlen(ttynam) + 1);
+	proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1);
 
 	if ((fd = dup(STDIN_FILENO)) == -1)
 		fatal("dup failed");
-	client_write_one(MSG_IDENTIFY_STDIN, fd, NULL, 0);
+	proc_send(client_peer, MSG_IDENTIFY_STDIN, fd, NULL, 0);
 
 	pid = getpid();
-	client_write_one(MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid);
+	proc_send(client_peer, MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid);
 
 	for (ss = environ; *ss != NULL; ss++) {
 		sslen = strlen(*ss) + 1;
 		if (sslen <= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
-			client_write_one(MSG_IDENTIFY_ENVIRON, -1, *ss, sslen);
-	}
-
-	client_write_one(MSG_IDENTIFY_DONE, -1, NULL, 0);
-}
-
-/* Helper to send one message. */
-int
-client_write_one(enum msgtype type, int fd, const void *buf, size_t len)
-{
-	int	retval;
-
-	retval = imsg_compose(&client_ibuf, type, PROTOCOL_VERSION, -1, fd,
-	    (void *)buf, len);
-	if (retval != 1)
-		return (-1);
-	return (0);
-}
-
-/* Write a message to the server without a file descriptor. */
-int
-client_write_server(enum msgtype type, const void *buf, size_t len)
-{
-	int	retval;
-
-	retval = client_write_one(type, -1, buf, len);
-	if (retval == 0)
-		client_update_event();
-	return (retval);
-}
-
-/* Update client event based on whether it needs to read or read and write. */
-void
-client_update_event(void)
-{
-	short	events;
-
-	event_del(&client_event);
-	events = EV_READ;
-	if (client_ibuf.w.queued > 0)
-		events |= EV_WRITE;
-	event_set(&client_event, client_ibuf.fd, events, client_callback, NULL);
-	event_add(&client_event, NULL);
-}
-
-/* Callback to handle signals in the client. */
-void
-client_signal(int sig, unused short events, unused void *arg)
-{
-	struct sigaction sigact;
-	int		 status;
-
-	if (sig == SIGCHLD)
-		waitpid(WAIT_ANY, &status, WNOHANG);
-	else if (!client_attached) {
-		if (sig == SIGTERM)
-			event_loopexit(NULL);
-	} else {
-		switch (sig) {
-		case SIGHUP:
-			client_exitreason = CLIENT_EXIT_LOST_TTY;
-			client_exitval = 1;
-			client_write_server(MSG_EXITING, NULL, 0);
-			break;
-		case SIGTERM:
-			client_exitreason = CLIENT_EXIT_TERMINATED;
-			client_exitval = 1;
-			client_write_server(MSG_EXITING, NULL, 0);
-			break;
-		case SIGWINCH:
-			client_write_server(MSG_RESIZE, NULL, 0);
-			break;
-		case SIGCONT:
-			memset(&sigact, 0, sizeof sigact);
-			sigemptyset(&sigact.sa_mask);
-			sigact.sa_flags = SA_RESTART;
-			sigact.sa_handler = SIG_IGN;
-			if (sigaction(SIGTSTP, &sigact, NULL) != 0)
-				fatal("sigaction failed");
-			client_write_server(MSG_WAKEUP, NULL, 0);
-			break;
-		}
+			proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen);
 	}
 
-	client_update_event();
-}
-
-/* Callback for client imsg read events. */
-void
-client_callback(unused int fd, short events, unused void *arg)
-{
-	ssize_t	n;
-	int	retval;
-
-	if (events & EV_READ) {
-		if ((n = imsg_read(&client_ibuf)) == -1 || n == 0)
-			goto lost_server;
-		if (client_attached)
-			retval = client_dispatch_attached();
-		else
-			retval = client_dispatch_wait();
-		if (retval != 0) {
-			event_loopexit(NULL);
-			return;
-		}
-	}
-
-	if (events & EV_WRITE) {
-		if (msgbuf_write(&client_ibuf.w) <= 0 && errno != EAGAIN)
-			goto lost_server;
-	}
-
-	client_update_event();
-	return;
-
-lost_server:
-	client_exitreason = CLIENT_EXIT_LOST_SERVER;
-	client_exitval = 1;
-	event_loopexit(NULL);
+	proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0);
 }
 
 /* Callback for client stdin read events. */
@@ -544,10 +419,9 @@ client_stdin_callback(unused int fd, unused short events, unused void *arg)
 	if (data.size < 0 && (errno == EINTR || errno == EAGAIN))
 		return;
 
-	client_write_server(MSG_STDIN, &data, sizeof data);
+	proc_send(client_peer, MSG_STDIN, -1, &data, sizeof data);
 	if (data.size <= 0)
 		event_del(&client_stdin);
-	client_update_event();
 }
 
 /* Force write to file descriptor. */
@@ -597,13 +471,65 @@ client_exec(const char *shell)
 	fatal("execl failed");
 }
 
+/* Callback to handle signals in the client. */
+void
+client_signal(int sig)
+{
+	struct sigaction sigact;
+	int		 status;
+
+	if (sig == SIGCHLD)
+		waitpid(WAIT_ANY, &status, WNOHANG);
+	else if (!client_attached) {
+		if (sig == SIGTERM)
+			proc_exit(client_proc);
+	} else {
+		switch (sig) {
+		case SIGHUP:
+			client_exitreason = CLIENT_EXIT_LOST_TTY;
+			client_exitval = 1;
+			proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+			break;
+		case SIGTERM:
+			client_exitreason = CLIENT_EXIT_TERMINATED;
+			client_exitval = 1;
+			proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+			break;
+		case SIGWINCH:
+			proc_send(client_peer, MSG_RESIZE, -1, NULL, 0);
+			break;
+		case SIGCONT:
+			memset(&sigact, 0, sizeof sigact);
+			sigemptyset(&sigact.sa_mask);
+			sigact.sa_flags = SA_RESTART;
+			sigact.sa_handler = SIG_IGN;
+			if (sigaction(SIGTSTP, &sigact, NULL) != 0)
+				fatal("sigaction failed");
+			proc_send(client_peer, MSG_WAKEUP, -1, NULL, 0);
+			break;
+		}
+	}
+}
+
+/* Callback for client read events. */
+void
+client_dispatch(struct imsg *imsg, unused void *arg)
+{
+	if (imsg == NULL) {
+		client_exitreason = CLIENT_EXIT_LOST_SERVER;
+		client_exitval = 1;
+	} else if (client_attached)
+		client_dispatch_attached(imsg);
+	else
+		client_dispatch_wait(imsg);
+}
+
 /* Dispatch imsgs when in wait state (before MSG_READY). */
-int
-client_dispatch_wait(void)
+void
+client_dispatch_wait(struct imsg *imsg)
 {
-	struct imsg		 imsg;
 	char			*data;
-	ssize_t			 n, datalen;
+	ssize_t			 datalen;
 	struct msg_stdout_data	 stdoutdata;
 	struct msg_stderr_data	 stderrdata;
 	int			 retval;
@@ -623,163 +549,141 @@ client_dispatch_wait(void)
 	};
 #endif
 
-	for (;;) {
-		if ((n = imsg_get(&client_ibuf, &imsg)) == -1)
-			fatalx("imsg_get failed");
-		if (n == 0)
-			return (0);
-
-		data = imsg.data;
-		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
-
-		log_debug("got %u from server", imsg.hdr.type);
-		switch (imsg.hdr.type) {
-		case MSG_EXIT:
-		case MSG_SHUTDOWN:
-			if (datalen != sizeof retval && datalen != 0)
-				fatalx("bad MSG_EXIT size");
-			if (datalen == sizeof retval) {
-				memcpy(&retval, data, sizeof retval);
-				client_exitval = retval;
-			}
-			imsg_free(&imsg);
-			return (-1);
-		case MSG_READY:
-			if (datalen != 0)
-				fatalx("bad MSG_READY size");
-
-			event_del(&client_stdin);
-			client_attached = 1;
-			client_write_server(MSG_RESIZE, NULL, 0);
-			break;
-		case MSG_STDIN:
-			if (datalen != 0)
-				fatalx("bad MSG_STDIN size");
-
-			event_add(&client_stdin, NULL);
-			break;
-		case MSG_STDOUT:
-			if (datalen != sizeof stdoutdata)
-				fatalx("bad MSG_STDOUT size");
-			memcpy(&stdoutdata, data, sizeof stdoutdata);
-
-			client_write(STDOUT_FILENO, stdoutdata.data,
-			    stdoutdata.size);
-			break;
-		case MSG_STDERR:
-			if (datalen != sizeof stderrdata)
-				fatalx("bad MSG_STDERR size");
-			memcpy(&stderrdata, data, sizeof stderrdata);
+	data = imsg->data;
+	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
+
+	switch (imsg->hdr.type) {
+	case MSG_EXIT:
+	case MSG_SHUTDOWN:
+		if (datalen != sizeof retval && datalen != 0)
+			fatalx("bad MSG_EXIT size");
+		if (datalen == sizeof retval) {
+			memcpy(&retval, data, sizeof retval);
+			client_exitval = retval;
+		}
+		proc_exit(client_proc);
+		break;
+	case MSG_READY:
+		if (datalen != 0)
+			fatalx("bad MSG_READY size");
 
-			client_write(STDERR_FILENO, stderrdata.data,
-			    stderrdata.size);
-			break;
-		case MSG_VERSION:
-			if (datalen != 0)
-				fatalx("bad MSG_VERSION size");
+		event_del(&client_stdin);
+		client_attached = 1;
+		proc_send(client_peer, MSG_RESIZE, -1, NULL, 0);
+		break;
+	case MSG_STDIN:
+		if (datalen != 0)
+			fatalx("bad MSG_STDIN size");
 
-			fprintf(stderr, "protocol version mismatch "
-			    "(client %d, server %u)\n", PROTOCOL_VERSION,
-			    imsg.hdr.peerid);
-			client_exitval = 1;
+		event_add(&client_stdin, NULL);
+		break;
+	case MSG_STDOUT:
+		if (datalen != sizeof stdoutdata)
+			fatalx("bad MSG_STDOUT size");
+		memcpy(&stdoutdata, data, sizeof stdoutdata);
 
-			imsg_free(&imsg);
-			return (-1);
-		case MSG_SHELL:
-			if (datalen == 0 || data[datalen - 1] != '\0')
-				fatalx("bad MSG_SHELL string");
-
-			clear_signals(0);
-			client_exec(data);
-			/* NOTREACHED */
-		case MSG_DETACH:
-		case MSG_DETACHKILL:
-			client_write_server(MSG_EXITING, NULL, 0);
-			break;
-		case MSG_EXITED:
-			imsg_free(&imsg);
-			return (-1);
-		}
+		client_write(STDOUT_FILENO, stdoutdata.data,
+		    stdoutdata.size);
+		break;
+	case MSG_STDERR:
+		if (datalen != sizeof stderrdata)
+			fatalx("bad MSG_STDERR size");
+		memcpy(&stderrdata, data, sizeof stderrdata);
 
-		imsg_free(&imsg);
+		client_write(STDERR_FILENO, stderrdata.data,
+		    stderrdata.size);
+		break;
+	case MSG_VERSION:
+		if (datalen != 0)
+			fatalx("bad MSG_VERSION size");
+
+		fprintf(stderr, "protocol version mismatch "
+		    "(client %d, server %u)\n", PROTOCOL_VERSION,
+		    imsg->hdr.peerid);
+		client_exitval = 1;
+		proc_exit(client_proc);
+		break;
+	case MSG_SHELL:
+		if (datalen == 0 || data[datalen - 1] != '\0')
+			fatalx("bad MSG_SHELL string");
+
+		clear_signals(0);
+		client_exec(data);
+		/* NOTREACHED */
+	case MSG_DETACH:
+	case MSG_DETACHKILL:
+		proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+		break;
+	case MSG_EXITED:
+		proc_exit(client_proc);
+		break;
 	}
 }
 
 /* Dispatch imsgs in attached state (after MSG_READY). */
-int
-client_dispatch_attached(void)
+void
+client_dispatch_attached(struct imsg *imsg)
 {
-	struct imsg		 imsg;
 	struct sigaction	 sigact;
 	char			*data;
-	ssize_t			 n, datalen;
-
-	for (;;) {
-		if ((n = imsg_get(&client_ibuf, &imsg)) == -1)
-			fatalx("imsg_get failed");
-		if (n == 0)
-			return (0);
-
-		data = imsg.data;
-		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
-
-		log_debug("got %u from server", imsg.hdr.type);
-		switch (imsg.hdr.type) {
-		case MSG_DETACH:
-		case MSG_DETACHKILL:
-			if (datalen == 0 || data[datalen - 1] != '\0')
-				fatalx("bad MSG_DETACH string");
-
-			client_exitsession = xstrdup(data);
-			client_exittype = imsg.hdr.type;
-			if (imsg.hdr.type == MSG_DETACHKILL)
-				client_exitreason = CLIENT_EXIT_DETACHED_HUP;
-			else
-				client_exitreason = CLIENT_EXIT_DETACHED;
-			client_write_server(MSG_EXITING, NULL, 0);
-			break;
-		case MSG_EXIT:
-			if (datalen != 0 && datalen != sizeof (int))
-				fatalx("bad MSG_EXIT size");
+	ssize_t			 datalen;
 
-			client_write_server(MSG_EXITING, NULL, 0);
-			client_exitreason = CLIENT_EXIT_EXITED;
-			break;
-		case MSG_EXITED:
-			if (datalen != 0)
-				fatalx("bad MSG_EXITED size");
+	data = imsg->data;
+	datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
 
-			imsg_free(&imsg);
-			return (-1);
-		case MSG_SHUTDOWN:
-			if (datalen != 0)
-				fatalx("bad MSG_SHUTDOWN size");
+	switch (imsg->hdr.type) {
+	case MSG_DETACH:
+	case MSG_DETACHKILL:
+		if (datalen == 0 || data[datalen - 1] != '\0')
+			fatalx("bad MSG_DETACH string");
 
-			client_write_server(MSG_EXITING, NULL, 0);
-			client_exitreason = CLIENT_EXIT_SERVER_EXITED;
-			client_exitval = 1;
-			break;
-		case MSG_SUSPEND:
-			if (datalen != 0)
-				fatalx("bad MSG_SUSPEND size");
+		client_exitsession = xstrdup(data);
+		client_exittype = imsg->hdr.type;
+		if (imsg->hdr.type == MSG_DETACHKILL)
+			client_exitreason = CLIENT_EXIT_DETACHED_HUP;
+		else
+			client_exitreason = CLIENT_EXIT_DETACHED;
+		proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+		break;
+	case MSG_EXIT:
+		if (datalen != 0 && datalen != sizeof (int))
+			fatalx("bad MSG_EXIT size");
 
-			memset(&sigact, 0, sizeof sigact);
-			sigemptyset(&sigact.sa_mask);
-			sigact.sa_flags = SA_RESTART;
-			sigact.sa_handler = SIG_DFL;
-			if (sigaction(SIGTSTP, &sigact, NULL) != 0)
-				fatal("sigaction failed");
-			kill(getpid(), SIGTSTP);
-			break;
-		case MSG_LOCK:
-			if (datalen == 0 || data[datalen - 1] != '\0')
-				fatalx("bad MSG_LOCK string");
+		proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+		client_exitreason = CLIENT_EXIT_EXITED;
+		break;
+	case MSG_EXITED:
+		if (datalen != 0)
+			fatalx("bad MSG_EXITED size");
 
-			system(data);
-			client_write_server(MSG_UNLOCK, NULL, 0);
-			break;
-		}
+		proc_exit(client_proc);
+		break;
+	case MSG_SHUTDOWN:
+		if (datalen != 0)
+			fatalx("bad MSG_SHUTDOWN size");
 
-		imsg_free(&imsg);
+		proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
+		client_exitreason = CLIENT_EXIT_SERVER_EXITED;
+		client_exitval = 1;
+		break;
+	case MSG_SUSPEND:
+		if (datalen != 0)
+			fatalx("bad MSG_SUSPEND size");
+
+		memset(&sigact, 0, sizeof sigact);
+		sigemptyset(&sigact.sa_mask);
+		sigact.sa_flags = SA_RESTART;
+		sigact.sa_handler = SIG_DFL;
+		if (sigaction(SIGTSTP, &sigact, NULL) != 0)
+			fatal("sigaction failed");
+		kill(getpid(), SIGTSTP);
+		break;
+	case MSG_LOCK:
+		if (datalen == 0 || data[datalen - 1] != '\0')
+			fatalx("bad MSG_LOCK string");
+
+		system(data);
+		proc_send(client_peer, MSG_UNLOCK, -1, NULL, 0);
+		break;
 	}
 }
diff --git a/cmd-attach-session.c b/cmd-attach-session.c
index a7ef1cd9..a3623ec4 100644
--- a/cmd-attach-session.c
+++ b/cmd-attach-session.c
@@ -113,21 +113,15 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 
 	if (c->session != NULL) {
 		if (dflag) {
-			/*
-			 * Can't use server_write_session in case attaching to
-			 * the same session as currently attached to.
-			 */
 			TAILQ_FOREACH(c_loop, &clients, entry) {
 				if (c_loop->session != s || c == c_loop)
 					continue;
-				server_write_client(c, MSG_DETACH,
-				    c_loop->session->name,
-				    strlen(c_loop->session->name) + 1);
+				proc_send_s(c->peer, MSG_DETACH, s->name);
 			}
 		}
 
 		if (!Eflag) {
-			update = options_get_string(&s->options,
+			update = options_get_string(s->options,
 			    "update-environment");
 			environ_update(update, &c->environ, &s->environ);
 		}
@@ -150,12 +144,15 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 			c->flags |= CLIENT_READONLY;
 
 		if (dflag) {
-			server_write_session(s, MSG_DETACH, s->name,
-			    strlen(s->name) + 1);
+			TAILQ_FOREACH(c_loop, &clients, entry) {
+				if (c_loop->session != s || c == c_loop)
+					continue;
+				proc_send_s(c->peer, MSG_DETACH, s->name);
+			}
 		}
 
 		if (!Eflag) {
-			update = options_get_string(&s->options,
+			update = options_get_string(s->options,
 			    "update-environment");
 			environ_update(update, &c->environ, &s->environ);
 		}
@@ -168,7 +165,8 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 		server_redraw_client(c);
 		s->curw->flags &= ~WINLINK_ALERTFLAGS;
 
-		server_write_ready(c);
+		if (~c->flags & CLIENT_CONTROL)
+			proc_send(c->peer, MSG_READY, -1, NULL, 0);
 		cmdq->client_exit = 0;
 	}
 	recalculate_sizes();
diff --git a/cmd-break-pane.c b/cmd-break-pane.c
index 2aa5c5b7..39179cc7 100644
--- a/cmd-break-pane.c
+++ b/cmd-break-pane.c
@@ -84,7 +84,7 @@ cmd_break_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 	layout_init(w, wp);
 
 	if (idx == -1)
-		idx = -1 - options_get_number(&dst_s->options, "base-index");
+		idx = -1 - options_get_number(dst_s->options, "base-index");
 	wl = session_attach(dst_s, w, idx, &cause); /* can't fail */
 	if (!args_has(self->args, 'd'))
 		session_select(dst_s, wl->idx);
diff --git a/cmd-choose-buffer.c b/cmd-choose-buffer.c
index b4590306..e790de6b 100644
--- a/c