Add support for simple menus usable with mouse or keyboard. New command

display-menu shows a menu (bound to the mouse on status line by default)
and a couple of extra formats for the default menus.

8 files changed, 667 insertions, 23 deletions

diff --git a/usr.bin/tmux/Makefile b/usr.bin/tmux/Makefile
index e107e9ab099..4f93457924e 100644
--- a/usr.bin/tmux/Makefile
+++ b/usr.bin/tmux/Makefile
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.95 2019/04/26 11:38:51 nicm Exp $
+# $OpenBSD: Makefile,v 1.96 2019/05/10 18:04:06 nicm Exp $
 
 PROG=	tmux
 SRCS=	alerts.c \
@@ -15,6 +15,7 @@ SRCS=	alerts.c \
 	cmd-confirm-before.c \
 	cmd-copy-mode.c \
 	cmd-detach-client.c \
+	cmd-display-menu.c \
 	cmd-display-message.c \
 	cmd-display-panes.c \
 	cmd-find-window.c \
@@ -86,6 +87,7 @@ SRCS=	alerts.c \
 	layout-set.c \
 	layout.c \
 	log.c \
+	menu.c \
 	mode-tree.c \
 	names.c \
 	notify.c \
diff --git a/usr.bin/tmux/cmd-display-menu.c b/usr.bin/tmux/cmd-display-menu.c
new file mode 100644
index 00000000000..dfe4f9694d2
--- /dev/null
+++ b/usr.bin/tmux/cmd-display-menu.c
@@ -0,0 +1,163 @@
+/* $OpenBSD: cmd-display-menu.c,v 1.1 2019/05/10 18:04:06 nicm Exp $ */
+
+/*
+ * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+/*
+ * Display a menu on a client.
+ */
+
+static enum cmd_retval	cmd_display_menu_exec(struct cmd *,
+			    struct cmdq_item *);
+
+const struct cmd_entry cmd_display_menu_entry = {
+	.name = "display-menu",
+	.alias = "menu",
+
+	.args = { "c:FM:t:T:x:y:", 0, 0 },
+	.usage = "[-F] [-c target-client] [-M menu] " CMD_TARGET_PANE_USAGE " "
+	         "[-T title] [-x position] [-y position]",
+
+	.target = { 't', CMD_FIND_PANE, 0 },
+
+	.flags = CMD_AFTERHOOK,
+	.exec = cmd_display_menu_exec
+};
+
+static enum cmd_retval
+cmd_display_menu_exec(struct cmd *self, struct cmdq_item *item)
+{
+	struct args		*args = self->args;
+	struct client		*c;
+	struct session		*s = item->target.s;
+	struct winlink		*wl = item->target.wl;
+	struct window_pane	*wp = item->target.wp;
+	struct cmd_find_state	*fs = &item->target;
+	struct menu		*menu = NULL;
+	struct style_range	*sr;
+	const char		*string, *xp, *yp;
+	int			 at, flags;
+	u_int			 px, py, ox, oy, sx, sy;
+	char			*title;
+
+	if ((c = cmd_find_client(item, args_get(args, 'c'), 0)) == NULL)
+		return (CMD_RETURN_ERROR);
+	if (c->overlay_draw != NULL)
+		return (CMD_RETURN_NORMAL);
+	at = status_at_line(c);
+
+	string = args_get(args, 'M');
+	if (string == NULL) {
+		cmdq_error(item, "no menu specified");
+		return (CMD_RETURN_ERROR);
+	}
+	if (args_has(args, 'F'))
+		string = format_single(NULL, string, c, s, wl, wp);
+	else
+		string = xstrdup(string);
+	if (args_has(args, 'T'))
+		title = format_single(NULL, args_get(args, 'T'), c, s, wl, wp);
+	else
+		title = xstrdup("");
+	menu = menu_create_from_string(string, c, fs, title);
+	free(title);
+	if (menu == NULL) {
+		cmdq_error(item, "invalid menu %s", string);
+		return (CMD_RETURN_ERROR);
+	}
+	if (menu->count == 0) {
+		menu_free(menu);
+		return (CMD_RETURN_NORMAL);
+	}
+
+	xp = args_get(args, 'x');
+	if (xp == NULL)
+		px = 0;
+	else if (strcmp(xp, "R") == 0)
+		px = c->tty.sx - 1;
+	else if (strcmp(xp, "P") == 0) {
+		tty_window_offset(&c->tty, &ox, &oy, &sx, &sy);
+		if (wp->xoff >= ox)
+			px = wp->xoff - ox;
+		else
+			px = 0;
+	} else if (strcmp(xp, "M") == 0 && item->shared->mouse.valid) {
+		if (item->shared->mouse.x > (menu->width + 4) / 2)
+			px = item->shared->mouse.x - (menu->width + 4) / 2;
+		else
+			px = 0;
+	}
+	else if (strcmp(xp, "W") == 0) {
+		if (at == -1)
+			px = 0;
+		else {
+			TAILQ_FOREACH(sr, &c->status.entries[0].ranges, entry) {
+				if (sr->type != STYLE_RANGE_WINDOW)
+					continue;
+				if (sr->argument == (u_int)wl->idx)
+					break;
+			}
+			if (sr != NULL)
+				px = sr->start;
+			else
+				px = 0;
+		}
+	} else
+		px = strtoul(xp, NULL, 10);
+	if (px + menu->width + 4 >= c->tty.sx)
+		px = c->tty.sx - menu->width - 4;
+
+	yp = args_get(args, 'y');
+	if (yp == NULL)
+		py = 0;
+	else if (strcmp(yp, "P") == 0) {
+		tty_window_offset(&c->tty, &ox, &oy, &sx, &sy);
+		if (wp->yoff + wp->sy >= oy)
+			py = wp->yoff + wp->sy - oy;
+		else
+			py = 0;
+	} else if (strcmp(yp, "M") == 0 && item->shared->mouse.valid)
+		py = item->shared->mouse.y + menu->count + 2;
+	else if (strcmp(yp, "S") == 0) {
+		if (at == -1)
+			py = c->tty.sy;
+		else if (at == 0)
+			py = status_line_size(c) + menu->count + 2;
+		else
+			py = at;
+	} else
+		py = strtoul(yp, NULL, 10);
+	if (py < menu->count + 2)
+		py = 0;
+	else
+		py -= menu->count + 2;
+	if (py + menu->count + 2 >= c->tty.sy)
+		py = c->tty.sy - menu->count - 2;
+
+	flags = 0;
+	if (!item->shared->mouse.valid)
+		flags |= MENU_NOMOUSE;
+	if (menu_display(menu, flags, item, px, py, c, fs, NULL, NULL) != 0)
+		return (CMD_RETURN_NORMAL);
+	return (CMD_RETURN_WAIT);
+}
diff --git a/usr.bin/tmux/cmd.c b/usr.bin/tmux/cmd.c
index abb2e9a2917..e36a395e909 100644
--- a/usr.bin/tmux/cmd.c
+++ b/usr.bin/tmux/cmd.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd.c,v 1.147 2019/05/08 18:05:03 nicm Exp $ */
+/* $OpenBSD: cmd.c,v 1.148 2019/05/10 18:04:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -42,6 +42,7 @@ extern const struct cmd_entry cmd_confirm_before_entry;
 extern const struct cmd_entry cmd_copy_mode_entry;
 extern const struct cmd_entry cmd_delete_buffer_entry;
 extern const struct cmd_entry cmd_detach_client_entry;
+extern const struct cmd_entry cmd_display_menu_entry;
 extern const struct cmd_entry cmd_display_message_entry;
 extern const struct cmd_entry cmd_display_panes_entry;
 extern const struct cmd_entry cmd_down_pane_entry;
@@ -130,6 +131,7 @@ const struct cmd_entry *cmd_table[] = {
 	&cmd_copy_mode_entry,
 	&cmd_delete_buffer_entry,
 	&cmd_detach_client_entry,
+	&cmd_display_menu_entry,
 	&cmd_display_message_entry,
 	&cmd_display_panes_entry,
 	&cmd_find_window_entry,
diff --git a/usr.bin/tmux/format.c b/usr.bin/tmux/format.c
index ccfac2b2512..e393430fef6 100644
--- a/usr.bin/tmux/format.c
+++ b/usr.bin/tmux/format.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: format.c,v 1.191 2019/05/09 08:38:13 nicm Exp $ */
+/* $OpenBSD: format.c,v 1.192 2019/05/10 18:04:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -54,6 +54,49 @@ static void	 format_defaults_session(struct format_tree *,
 static void	 format_defaults_client(struct format_tree *, struct client *);
 static void	 format_defaults_winlink(struct format_tree *, struct winlink *);
 
+/* Default menus. */
+#define DEFAULT_CLIENT_MENU \
+	"Detach,d,detach-client|" \
+	"Detach & Kill,X,detach-client -P|" \
+	"Detach Others,o,detach-client -a|" \
+	"|" \
+	"#{?#{lock-command},Lock,},l,lock-client"
+#define DEFAULT_SESSION_MENU \
+	"Next,n,switch-client -n|" \
+	"Previous,p,switch-client -p|" \
+	"|" \
+	"Renumber,N,move-window -r|" \
+	"Rename,n,command-prompt -I \"#S\" \"rename-session -- '%%'\"|" \
+	"|" \
+	"New Session,s,new-session|" \
+	"New Window,w,new-window"
+#define DEFAULT_WINDOW_MENU \
+	"Swap Left,l,swap-window -t,-1|" \
+	"Swap Right,r,swap-window -t,+1|" \
+	"#{?pane_marked_set,,#[dim]}Swap Marked,s,swap-window|" \
+	"|" \
+	"Kill,X,kill-window|" \
+	"Respawn,R,respawn-window -k|" \
+	"|" \
+	"#{?pane_marked,Unmark,Mark},m,select-pane -m|" \
+	"Rename,n,command-prompt -I \"#W\" \"rename-window -- '%%'\"|" \
+	"|" \
+	"New After,w,new-window -a|" \
+	"New At End,W,new-window"
+#define DEFAULT_PANE_MENU \
+	"Horizontal Split,h,split-window -h|" \
+	"Vertical Split,v,split-window -v|" \
+	"|" \
+	"Swap Up,u,swap-pane -U|" \
+	"Swap Down,d,swap-pane -D|" \
+	"#{?pane_marked_set,,#[dim]}Swap Marked,s,swap-pane|" \
+	"|" \
+	"Kill,X,kill-pane|" \
+	"Respawn,R,respawn-pane -k|" \
+	"|" \
+	"#{?pane_marked,Unmark,Mark},m,select-pane -m|" \
+	"#{?window_zoomed_flag,Unzoom,Zoom},z,resize-pane -Z"
+
 /* Entry in format job tree. */
 struct format_job {
 	struct client		*client;
@@ -752,6 +795,11 @@ format_create(struct client *c, struct cmdq_item *item, int tag, int flags)
 		}
 	}
 
+	format_add(ft, "client_menu", "%s", DEFAULT_CLIENT_MENU);
+	format_add(ft, "session_menu", "%s", DEFAULT_SESSION_MENU);
+	format_add(ft, "window_menu", "%s", DEFAULT_WINDOW_MENU);
+	format_add(ft, "pane_menu", "%s", DEFAULT_PANE_MENU);
+
 	if (item != NULL) {
 		if (item->cmd != NULL)
 			format_add(ft, "command", "%s", item->cmd->entry->name);
diff --git a/usr.bin/tmux/key-bindings.c b/usr.bin/tmux/key-bindings.c
index c484f2301c2..375b939d775 100644
--- a/usr.bin/tmux/key-bindings.c
+++ b/usr.bin/tmux/key-bindings.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: key-bindings.c,v 1.90 2019/05/09 13:12:59 nicm Exp $ */
+/* $OpenBSD: key-bindings.c,v 1.91 2019/05/10 18:04:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -271,6 +271,7 @@ key_bindings_init(void)
 		"bind -r C-Down resize-pane -D",
 		"bind -r C-Left resize-pane -L",
 		"bind -r C-Right resize-pane -R",
+
 		"bind -n MouseDown1Pane select-pane -t=\\; send-keys -M",
 		"bind -n MouseDrag1Border resize-pane -M",
 		"bind -n MouseDown1Status select-window -t=",
@@ -279,6 +280,10 @@ key_bindings_init(void)
 		"bind -n MouseDrag1Pane if -Ft= '#{mouse_any_flag}' 'if -Ft= \"#{pane_in_mode}\" \"copy-mode -M\" \"send-keys -M\"' 'copy-mode -M'",
 		"bind -n MouseDown3Pane if-shell -Ft= '#{mouse_any_flag}' 'select-pane -t=; send-keys -M' 'select-pane -mt='",
 		"bind -n WheelUpPane if-shell -Ft= '#{mouse_any_flag}' 'send-keys -M' 'if -Ft= \"#{pane_in_mode}\" \"send-keys -M\" \"copy-mode -et=\"'",
+		"bind -n MouseDown3StatusRight display-menu -t= -xM -yS -F -M \"#{client_menu}\" -T \"#[align=centre]#{client_name}\"",
+		"bind -n MouseDown3StatusLeft display-menu -t= -xM -yS -F -M \"#{session_menu}\" -T \"#[align=centre]#{session_name}\"",
+		"bind -n MouseDown3Status display-menu -t= -xW -yS -F -M \"#{window_menu}\" -T \"#[align=centre]#{window_index}:#{window_name}\"",
+		"bind -n M-MouseDown3Pane display-menu -t= -xM -yM -F -M \"#{pane_menu}\" -T \"#[align=centre]#{pane_index} (#{pane_id})\"",
 
 		"bind -Tcopy-mode C-Space send -X begin-selection",
 		"bind -Tcopy-mode C-a send -X start-of-line",
diff --git a/usr.bin/tmux/menu.c b/usr.bin/tmux/menu.c
new file mode 100644
index 00000000000..f0452e7a5af
--- /dev/null
+++ b/usr.bin/tmux/menu.c
@@ -0,0 +1,342 @@
+/* $OpenBSD: menu.c,v 1.1 2019/05/10 18:04:06 nicm Exp $ */
+
+/*
+ * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+struct menu_data {
+	struct cmdq_item	*item;
+	int			 flags;
+
+	struct cmd_find_state	 fs;
+	struct screen		 s;
+
+	u_int			 px;
+	u_int			 py;
+
+	struct menu		*menu;
+	int			 choice;
+
+	menu_choice_cb		 cb;
+	void			*data;
+};
+
+static void
+menu_add_item(struct menu *menu, struct menu_item *item, struct client *c,
+    struct cmd_find_state *fs)
+{
+	struct menu_item	*new_item;
+	const char		*key;
+	char			*name;
+	u_int			 width;
+
+	menu->items = xreallocarray(menu->items, menu->count + 1,
+	    sizeof *menu->items);
+	new_item = &menu->items[menu->count++];
+	memset(new_item, 0, sizeof *new_item);
+
+	if (item == NULL || *item->name == '\0') /* horizontal line */
+		return;
+	name = format_single(NULL, item->name, c, fs->s, fs->wl, fs->wp);
+	if (*name == '\0') { /* no item if empty after format expanded */
+		menu->count--;
+		return;
+	}
+	if (item->key != KEYC_UNKNOWN) {
+		key = key_string_lookup_key(item->key);
+		xasprintf(&new_item->name, "%s #[align=right](%s)", name, key);
+	} else
+		xasprintf(&new_item->name, "%s", name);
+	free(name);
+
+	if (item->command != NULL)
+		new_item->command = xstrdup(item->command);
+	else
+		new_item->command = NULL;
+	new_item->key = item->key;
+
+	width = format_width(new_item->name);
+	if (width > menu->width)
+		menu->width = width;
+}
+
+static void
+menu_parse_item(struct menu *menu, const char *s, struct client *c,
+    struct cmd_find_state *fs)
+{
+	char			*copy, *first;
+	const char		*second, *third;
+	struct menu_item	 item;
+
+	first = copy = xstrdup(s);
+	if ((second = format_skip(first, ",")) != NULL) {
+		*(char *)second++ = '\0';
+		if ((third = format_skip(second, ",")) != NULL) {
+			*(char *)third++ = '\0';
+
+			item.name = first;
+			item.command = (char *)third;
+			item.key = key_string_lookup_string(second);
+			menu_add_item(menu, &item, c, fs);
+		}
+	}
+	free(copy);
+}
+
+struct menu *
+menu_create_from_items(struct menu_item *items, u_int count, struct client *c,
+    struct cmd_find_state *fs, const char *title)
+{
+	struct menu	*menu;
+	u_int		 i;
+
+	menu = xcalloc(1, sizeof *menu);
+	menu->title = xstrdup(title);
+
+	for (i = 0; i < count; i++)
+		menu_add_item(menu, &items[i], c, fs);
+
+	return (menu);
+}
+
+struct menu *
+menu_create_from_string(const char *s, struct client *c,
+    struct cmd_find_state *fs, const char *title)
+{
+	struct menu	*menu;
+	char		*copy, *string, *next;
+
+	if (*s == '\0')
+		return (NULL);
+
+	menu = xcalloc(1, sizeof *menu);
+	menu->title = xstrdup(title);
+
+	copy = string = xstrdup(s);
+	do {
+		next = (char *)format_skip(string, "|");
+		log_debug("XXX %s -- %s", next, string);
+		if (next != NULL)
+			*next++ = '\0';
+		if (*string == '\0')
+			menu_add_item(menu, NULL, c, fs);
+		else
+			menu_parse_item(menu, string, c, fs);
+		string = next;
+	} while (next != NULL);
+	free(copy);
+
+	return (menu);
+}
+
+void
+menu_free(struct menu *menu)
+{
+	u_int	i;
+
+	for (i = 0; i < menu->count; i++) {
+		free(menu->items[i].name);
+		free(menu->items[i].command);
+	}
+	free(menu->items);
+
+	free(menu->title);
+	free(menu);
+}
+
+static void
+menu_draw_cb(struct client *c, __unused struct screen_redraw_ctx *ctx0)
+{
+	struct menu_data	*md = c->overlay_data;
+	struct tty		*tty = &c->tty;
+	struct screen		*s = &md->s;
+	struct menu		*menu = md->menu;
+	struct screen_write_ctx	 ctx;
+	u_int			 i, px, py;
+
+	screen_write_start(&ctx, NULL, s);
+	screen_write_clearscreen(&ctx, 8);
+	screen_write_menu(&ctx, menu, md->choice);
+	screen_write_stop(&ctx);
+
+	px = md->px;
+	py = md->py;
+
+	for (i = 0; i < screen_size_y(&md->s); i++)
+		tty_draw_line(tty, NULL, s, 0, i, menu->width + 4, px, py + i);
+
+	if (~md->flags & MENU_NOMOUSE)
+		tty_update_mode(tty, MODE_MOUSE_ALL, NULL);
+}
+
+static void
+menu_free_cb(struct client *c)
+{
+	struct menu_data	*md = c->overlay_data;
+
+	if (md->item != NULL)
+		md->item->flags &= ~CMDQ_WAITING;
+
+	screen_free(&md->s);
+	menu_free(md->menu);
+	free(md);
+}
+
+static enum cmd_retval
+menu_error_cb(struct cmdq_item *item, void *data)
+{
+	char	*error = data;
+
+	cmdq_error(item, "%s", error);
+	free(error);
+
+	return (CMD_RETURN_NORMAL);
+}
+
+static int
+menu_key_cb(struct client *c, struct key_event *event)
+{
+	struct menu_data		*md = c->overlay_data;
+	struct menu			*menu = md->menu;
+	struct mouse_event		*m = &event->m;
+	u_int				 i;
+	int				 count = menu->count, old = md->choice;
+	const struct menu_item		*item;
+	struct cmd_list			*cmdlist;
+	struct cmdq_item		*new_item;
+	char				*cause;
+
+	if (KEYC_IS_MOUSE(event->key)) {
+		if (md->flags & MENU_NOMOUSE)
+			return (0);
+		if (m->x < md->px ||
+		    m->x > md->px + 4 + menu->width ||
+		    m->y < md->py + 1 ||
+		    m->y > md->py + 1 + count - 1) {
+			if (MOUSE_RELEASE(m->b))
+				return (1);
+			if (md->choice != -1) {
+				md->choice = -1;
+				c->flags |= CLIENT_REDRAWOVERLAY;
+			}
+			return (0);
+		}
+		md->choice = m->y - (md->py + 1);
+		if (MOUSE_RELEASE(m->b))
+			goto chosen;
+		if (md->choice != old)
+			c->flags |= CLIENT_REDRAWOVERLAY;
+		return (0);
+	}
+	switch (event->key) {
+	case KEYC_UP:
+		do {
+			if (md->choice == -1 || md->choice == 0)
+				md->choice = count - 1;
+			else
+				md->choice--;
+		} while (menu->items[md->choice].name == NULL);
+		c->flags |= CLIENT_REDRAWOVERLAY;
+		return (0);
+	case KEYC_DOWN:
+		do {
+			if (md->choice == -1 || md->choice == count - 1)
+				md->choice = 0;
+		else
+			md->choice++;
+		} while (menu->items[md->choice].name == NULL);
+		c->flags |= CLIENT_REDRAWOVERLAY;
+		return (0);
+	case '\r':
+		goto chosen;
+	case '\033': /* Escape */
+	case '\003': /* C-c */
+	case '\007': /* C-g */
+	case 'q':
+		return (1);
+	}
+	for (i = 0; i < (u_int)count; i++) {
+		if (event->key == menu->items[i].key) {
+			md->choice = i;
+			goto chosen;
+		}
+	}
+	return (0);
+
+chosen:
+	if (md->choice == -1)
+		return (1);
+	item = &menu->items[md->choice];
+	if (item->name == NULL)
+		return (1);
+	if (md->cb != NULL) {
+	    md->cb(md->menu, md->choice, item->key, md->data);
+	    return (1);
+	}
+	cmdlist = cmd_string_parse(item->command, NULL, 0, &cause);
+	if (cmdlist == NULL && cause != NULL)
+		new_item = cmdq_get_callback(menu_error_cb, cause);
+	else if (cmdlist == NULL)
+		new_item = NULL;
+	else {
+		new_item = cmdq_get_command(cmdlist, &md->fs, NULL, 0);
+		cmd_list_free(cmdlist);
+	}
+	if (new_item != NULL) {
+		if (md->item != NULL)
+			cmdq_insert_after(md->item, new_item);
+		else
+			cmdq_append(c, new_item);
+	}
+	return (1);
+}
+
+int
+menu_display(struct menu *menu, int flags, struct cmdq_item *item, u_int px,
+    u_int py, struct client *c, struct cmd_find_state *fs, menu_choice_cb cb,
+    void *data)
+{
+	struct menu_data	*md;
+
+	if (c->tty.sx < menu->width + 4 || c->tty.sy < menu->count + 2)
+		return (-1);
+
+	md = xcalloc(1, sizeof *md);
+	md->item = item;
+	md->flags = flags;
+
+	cmd_find_copy_state(&md->fs, fs);
+	screen_init(&md->s, menu->width + 4, menu->count + 2, 0);
+
+	md->px = px;
+	md->py = py;
+
+	md->menu = menu;
+	md->choice = -1;
+
+	md->cb = cb;
+	md->data = data;
+
+	server_client_set_overlay(c, 0, menu_draw_cb, menu_key_cb, menu_free_cb,
+	    md);
+	return (0);
+}
diff --git a/usr.bin/tmux/tmux.1 b/usr.bin/tmux/tmux.1
index 765b145d2f0..c746c624f49 100644
--- a/usr.bin/tmux/tmux.1
+++ b/usr.bin/tmux/tmux.1
@@ -1,4 +1,4 @@
-.\" $OpenBSD: tmux.1,v 1.645 2019/05/09 08:38:13 nicm Exp $
+.\" $OpenBSD: tmux.1,v 1.646 2019/05/10 18:04:06 nicm Exp $
 .\"
 .\" Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 .\"
@@ -14,7 +14,7 @@
 .\" IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 .\" OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: May 9 2019 $
+.Dd $Mdocdate: May 10 2019 $
 .Dt TMUX 1
 .Os
 .Sh NAME
@@ -3909,12 +3909,13 @@ The following variables are available, where appropriate:
 .It Li "buffer_sample" Ta "" Ta "Sample of start of buffer"
 .It Li "buffer_size" Ta "" Ta "Size of the specified buffer in bytes"
 .It Li "client_activity" Ta "" Ta "Time client last had activity"
-.It Li "client_created" Ta "" Ta "Time client created"
 .It Li "client_control_mode" Ta "" Ta "1 if client is in control mode"
+.It Li "client_created" Ta "" Ta "Time client created"
 .It Li "client_discarded" Ta "" Ta "Bytes discarded when client behind"
 .It Li "client_height" Ta "" Ta "Height of client"
 .It Li "client_key_table" Ta "" Ta "Current key table"
 .It Li "client_last_session" Ta "" Ta "Name of the client's last session"
+.It Li "client_menu" Ta "" Ta "The default client menu"
 .It Li "client_name" Ta "" Ta "Name of client"
 .It Li "client_pid" Ta "" Ta "PID of client process"
 .It Li "client_prefix" Ta "" Ta "1 if prefix key has been pressed"
@@ -3927,11 +3928,11 @@ The following variables are available, where appropriate:
 .It Li "client_width" Ta "" Ta "Width of client"
 .It Li "client_written" Ta "" Ta "Bytes written to client"
 .It Li "command" Ta "" Ta "Name of command in use, if any"
-.It Li "command_list_name" Ta "" Ta "Command name if listing commands"
 .It Li "command_list_alias" Ta "" Ta "Command alias if listing commands"
+.It Li "command_list_name" Ta "" Ta "Command name if listing commands"
 .It Li "command_list_usage" Ta "" Ta "Command usage if listing commands"
-.It Li "cursor_flag" Ta "" Ta "Pane cursor flag"
 .It Li "cursor_character" Ta "" Ta "Character at cursor in pane"
+.It Li "cursor_flag" Ta "" Ta "Pane cursor flag"
 .It Li "cursor_x" Ta "" Ta "Cursor X position in pane"
 .It Li "cursor_y" Ta "" Ta "Cursor Y position in pane"
 .It Li "history_bytes" Ta "" Ta "Number of bytes in window history"
@@ -3949,10 +3950,10 @@ The following variables are available, where appropriate:
 .It Li "keypad_cursor_flag" Ta "" Ta "Pane keypad cursor flag"
 .It Li "keypad_flag" Ta "" Ta "Pane keypad flag"
 .It Li "line" Ta "" Ta "Line number in the list"
+.It Li "mouse_all_flag" Ta "" Ta "Pane mouse all flag"
 .It Li "mouse_any_flag" Ta "" Ta "Pane mouse any flag"
 .It Li "mouse_button_flag" Ta "" Ta "Pane mouse button flag"
 .It Li "mouse_standard_flag" Ta "" Ta "Pane mouse standard flag"
-.It Li "mouse_all_flag" Ta "" Ta "Pane mouse all flag"
 .It Li "pane_active" Ta "" Ta "1 if active pane"
 .It Li "pane_at_bottom" Ta "" Ta "1 if pane is at the bottom of window"
 .It Li "pane_at_left" Ta "" Ta "1 if pane is at the left of window"
@@ -3966,11 +3967,12 @@ The following variables are available, where appropriate:
 .It Li "pane_height" Ta "" Ta "Height of pane"
 .It Li "pane_id" Ta "#D" Ta "Unique pane ID"
 .It Li "pane_in_mode" Ta "" Ta "If pane is in a mode"
-.It Li "pane_input_off" Ta "" Ta "If input to pane is disabled"
 .It Li "pane_index" Ta "#P" Ta "Index of pane"
+.It Li "pane_input_off" Ta "" Ta "If input to pane is disabled"
 .It Li "pane_left" Ta "" Ta "Left of pane"
 .It Li "pane_marked" Ta " Ta "1 if this is the marked pane"
 .It Li "pane_marked_set" Ta " Ta "1 if a market pane is set"
+.It Li "pane_menu" Ta "" Ta "The default pane menu"
 .It Li "pane_mode" Ta "" Ta "Name of pane mode, if any."
 .It Li "pane_pid" Ta "" Ta "PID of first process in pane"
 .It Li "pane_pipe" Ta "" Ta "1 if pane is being piped"
@@ -3985,30 +3987,31 @@ The following variables are available, where appropriate:
 .It Li "pane_width" Ta "" Ta "Width of pane"
 .It Li "pid" Ta ""  Ta "Server PID"
 .It Li "rectangle_toggle" Ta "" Ta "1 if rectangle selection is activated"
+.It Li "scroll_position" Ta "" Ta "Scroll position in copy mode"
 .It Li "scroll_region_lower" Ta "" Ta "Bottom of scroll region in pane"
 .It Li "scroll_region_upper" Ta "" Ta "Top of scroll region in pane"
-.It Li "scroll_position" Ta "" Ta "Scroll position in copy mode"
 .It Li "selection_present" Ta "" Ta "1 if selection started in copy mode"
+.It Li "session_activity" Ta "" Ta "Time of session last activity"
 .It Li "session_alerts" Ta "" Ta "List of window indexes with alerts"
 .It Li "session_attached" Ta "" Ta "Number of clients session is attached to"
-.It Li "session_activity" Ta "" Ta "Time of session last activity"
 .It Li "session_created" Ta "" Ta "Time session created"
 .It Li "session_format" Ta "" Ta "1 if format is for a session (not assuming the current)"
-.It Li "session_last_attached" Ta "" Ta "Time session last attached"
 .It Li "session_group" Ta "" Ta "Name of session group"
-.It Li "session_group_size" Ta "" Ta "Size of session group"
 .It Li "session_group_list" Ta "" Ta "List of sessions in group"
+.It Li "session_group_size" Ta "" Ta "Size of session group"
 .It Li "session_grouped" Ta "" Ta "1 if session in a group"
 .It Li "session_id" Ta "" Ta "Unique session ID"
+.It Li "session_last_attached" Ta "" Ta "Time session last attached"
 .It Li "session_many_attached" Ta "" Ta "1 if multiple clients attached"
+.It Li "session_menu" Ta "" Ta "The default session menu"
 .It Li "session_name" Ta "#S" Ta "Name of session"
 .It Li "session_stack" Ta "" Ta "Window indexes in most recent order"
 .It Li "session_windows" Ta "" Ta "Number of windows in session"
 .It Li "socket_path" Ta "" Ta "Server socket path"
 .It Li "start_time" Ta "" Ta "Server start time"
+.It Li "window_active" Ta "" Ta "1 if window active"
 .It Li "window_activity" Ta "" Ta "Time of window last activity"
 .It Li "window_activity_flag" Ta "" Ta "1 if window has activity"
-.It Li "window_active" Ta "" Ta "1 if window active"
 .It Li "window_bell_flag" Ta "" Ta "1 if window has bell"
 .It Li "window_bigger" Ta "" Ta "1 if window is larger than client"
 .It Li "window_end_flag" Ta "" Ta "1 if window has the highest index"
@@ -4020,6 +4023,7 @@ The following variables are available, where appropriate:
 .It Li "window_last_flag" Ta "" Ta "1 if window is the last used"
 .It Li "window_layout" Ta "" Ta "Window layout description, ignoring zoomed window panes"
 .It Li "window_linked" Ta "" Ta "1 if window is linked across sessions"
+.It Li "window_menu" Ta "" Ta "The default window menu"
 .It Li "window_name" Ta "#W" Ta "Name of window"
 .It Li "window_offset_x" Ta "" Ta "X offset into window if larger than client"
 .It Li "window_offset_y" Ta "" Ta "Y offset into window if larger than client"
@@ -4436,6 +4440,74 @@ option.
 .Pp
 This command works only from inside
 .Nm .
+.It Xo Ic display-menu
+.Op Fl F
+.Op Fl c Ar target-client
+.Op Fl M Ar menu
+.Op Fl t Ar target-pane
+.Op Fl T Ar title
+.Op Fl x Ar position
+.Op Fl y Ar position
+.Xc
+.D1 (alias: Ic menu)
+Display a menu on
+.Ar target-client .
+.Ar target-pane
+gives the target for any commands run from the menu.
+.Pp
+A menu is passed to
+.Fl M
+as a list of menu items separated by
+.Ql | .
+Each menu item consists of three comma-separated parts:
+.Bl -enum -width Ds
+.It name
+The menu item name.
+This is a format and may include embedded styles, see the
+.Sx FORMATS
+and
+.Sx STYLES
+sections.
+.It key
+The menu item shortcut key.
+If this is empty the menu item has no key shortcut.
+.It command
+The command run when the menu item is chosen.
+.El
+.Pp
+An empty menu item is a separator line.
+.Pp
+.Fl T
+is a format for the menu title (see
+.Sx FORMATS ) .
+.Pp
+.Fl x
+and
+.Fl y
+give the position of the menu.
+Both may be a row or column number, or one of the following special values:
+.Bl -column "XXXXX" "XXXX" -offset indent
+.It Sy "Value" Ta Sy "Flag" Ta Sy "Meaning"
+.It Li "R" Ta Fl x Ta "The right side of the terminal"
+.It Li "P" Ta "Both" Ta "The bottom left of the pane"
+.It Li "M" Ta "Both" Ta "The mouse position"
+.It Li "W" Ta Fl x Ta "The window position on the status line"
+.It Li "S" Ta Fl y Ta "The line above or below the status line"
+.El
+.Pp
+Each menu consists of items followed by a key shortcut shown in brackets.
+If the menu is too large to fit on the terminal, it is not displayed.
+Pressing the key shortcut chooses the corresponding item.
+If the mouse is enabled and the menu is opened from a mouse key binding, releasing
+the mouse button with an item selected will choose that item.
+The following keys are also available:
+.Bl -column "Key" "Function" -offset indent
+.It Sy "Key" Ta Sy "Function"
+.It Li "Enter" Ta "Choose selected item"
+.It Li "Up" Ta "Select previous item"
+.It Li "Down" Ta "Select next item"
+.It Li "q" Ta "Exit menu"
+.El
 .It Xo Ic display-message
 .Op Fl aIpv
 .Op Fl c Ar target-client
diff --git a/usr.bin/tmux/tmux.h b/usr.bin/tmux/tmux.h
index 74bf710149b..7ff83cd7e2c 100644
--- a/usr.bin/tmux/tmux.h
+++ b/usr.bin/tmux/tmux.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.894 2019/05/10 14:12:47 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.895 2019/05/10 18:04:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -748,20 +748,20 @@ struct screen_redraw_ctx {
 #define screen_hsize(s) ((s)->grid->hsize)
 #define screen_hlimit(s) ((s)->grid->hlimit)
 
-/* Menu item. */
+/* Menu. */
 struct menu_item {
-	char			*name;
-	char			*command;
-	key_code		 key;
+	char		*name;
+	char		*command;
+	key_code	 key;
 };
-
-/* Menu. */
 struct menu {
 	char			*title;
 	struct menu_item	*items;
 	u_int			 count;
 	u_int			 width;
 };
+typedef void (*menu_choice_cb)(struct menu *, u_int, key_code, void *);
+#define MENU_NOMOUSE 0x1
 
 /*
  * Window mode. Windows can be in several modes and this is used to call the
@@ -2550,6 +2550,16 @@ void printflike(1, 2) log_debug(const char *, ...);
 __dead void printflike(1, 2) fatal(const char *, ...);
 __dead void printflike(1, 2) fatalx(const char *, ...);
 
+/* menu.c */
+struct menu	*menu_create_from_items(struct menu_item *, u_int,
+		    struct client *, struct cmd_find_state *, const char *);
+struct menu	*menu_create_from_string(const char *, struct client *,
+		    struct cmd_find_state *, const char *);
+void		 menu_free(struct menu *);
+int		 menu_display(struct menu *, int, struct cmdq_item *, u_int,
+		    u_int, struct client *, struct cmd_find_state *,
+		    menu_choice_cb, void *);
+
 /* style.c */
 int		 style_parse(struct style *,const struct grid_cell *,
 		     const char *);