Change send-keys -K to insert keys in the right place in the queue, like

we already do for key bindings. GitHub issue 3476.

cmd-send-keys.c

@@ -70,6 +70,7 @@ cmd_send_keys_inject_key(struct cmdq_item *item, struct cmdq_item *after,
 	struct key_table		*table = NULL;
 	struct key_binding		*bd;
 	struct key_event		*event;
+	struct cmdq_item		*new_after = after;
 
 	if (args_has(args, 'K')) {
 		if (tc == NULL)
@@ -77,10 +78,16 @@ cmd_send_keys_inject_key(struct cmdq_item *item, struct cmdq_item *after,
 		event = xcalloc(1, sizeof *event);
 		event->key = key|KEYC_SENT;
 		memset(&event->m, 0, sizeof event->m);
-		if (server_client_handle_key(tc, event) == 0) {
+		if (after == NULL) {
+			if (server_client_handle_key(tc, event) != 0)
+				return (item);
+		} else {
+			if (server_client_handle_key_after(tc, event, after,
+			    &new_after) != 0)
+				return (new_after);
+		}
 		free(event->buf);
 		free(event);
-		}
 		return (item);
 	}
 
@@ -229,8 +236,10 @@ cmd_send_keys_exec(struct cmd *self, struct cmdq_item *item)
 	if (count == 0) {
 		if (args_has(args, 'N') || args_has(args, 'R'))
 			return (CMD_RETURN_NORMAL);
+		after = args_has(args, 'K') ? item : NULL;
 		for (; np != 0; np--)
-			cmd_send_keys_inject_key(item, NULL, args, event->key);
+			after = cmd_send_keys_inject_key(item, after, args,
+			    event->key);
 		return (CMD_RETURN_NORMAL);
 	}
 

server-client.c

@@ -1168,11 +1168,11 @@ server_client_repeat_time(struct client *c, struct key_binding *bd)
 static enum cmd_retval
 server_client_key_callback(struct cmdq_item *item, void *data)
 {
-	struct client			*c = cmdq_get_client(item);
 	struct key_event		*event = data;
+	struct client			*c, *ec = event->client;
 	key_code			 key = event->key;
 	struct mouse_event		*m = &event->m;
-	struct session			*s = c->session;
+	struct session			*s;
 	struct winlink			*wl;
 	struct window_pane		*wp;
 	struct window_mode_entry	*wme;
@@ -1184,6 +1184,12 @@ server_client_key_callback(struct cmdq_item *item, void *data)
 	struct cmd_find_state		 fs;
 	key_code			 key0, prefix, prefix2;
 
+	if (ec != NULL)
+		c = ec;
+	else
+		c = cmdq_get_client(item);
+	s = c->session;
+
 	/* Check the client is good to accept input. */
 	if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
 		goto out;
@@ -1430,14 +1436,17 @@ paste_key:
 out:
 	if (s != NULL && key != KEYC_FOCUS_OUT)
 		server_client_update_latest(c);
+	if (ec != NULL)
+		server_client_unref(ec);
 	free(event->buf);
 	free(event);
 	return (CMD_RETURN_NORMAL);
 }
 
 /* Handle a key event. */
-int
+static int
-server_client_handle_key(struct client *c, struct key_event *event)
+server_client_handle_key0(struct client *c, struct key_event *event,
+    struct cmdq_item *after, struct cmdq_item **next)
 {
 	struct session		*s = c->session;
 	struct cmdq_item	*item;
@@ -1491,10 +1500,31 @@ server_client_handle_key(struct client *c, struct key_event *event)
 	 * previous keys.
 	 */
 	item = cmdq_get_callback(server_client_key_callback, event);
+	if (after != NULL) {
+		event->client = c;
+		c->references++;
+		item = cmdq_insert_after(after, item);
+		if (next != NULL)
+			*next = item;
+		return (1);
+	}
 	cmdq_append(c, item);
 	return (1);
 }
 
+int
+server_client_handle_key(struct client *c, struct key_event *event)
+{
+	return (server_client_handle_key0(c, event, NULL, NULL));
+}
+
+int
+server_client_handle_key_after(struct client *c, struct key_event *event,
+    struct cmdq_item *after, struct cmdq_item **next)
+{
+	return (server_client_handle_key0(c, event, after, next));
+}
+
 /* Client functions that need to happen every loop. */
 void
 server_client_loop(void)

tmux.h

@@ -1585,6 +1585,8 @@ struct mouse_event {
 
 /* Key event. */
 struct key_event {
+	struct client		*client;
+
 	key_code		 key;
 	struct mouse_event	 m;
 
@@ -3036,6 +3038,8 @@ void	 server_client_set_key_table(struct client *, const char *);
 const char *server_client_get_key_table(struct client *);
 int	 server_client_check_nested(struct client *);
 int	 server_client_handle_key(struct client *, struct key_event *);
+int	 server_client_handle_key_after(struct client *, struct key_event *,
+	     struct cmdq_item *, struct cmdq_item **);
 struct client *server_client_create(int);
 int	 server_client_open(struct client *, char **);
 void	 server_client_unref(struct client *);