config: add locked-title=no|yes

Closes #386

CHANGELOG.md

@@ -30,6 +30,11 @@
 
 ## Unreleased
 ### Added
+
+* `locked-title=no|yes` to `foot.ini`
+  (https://codeberg.org/dnkl/foot/issues/386).
+
+
 ### Changed
 
 * Non-empty lines are now considered to have a hard linebreak,

config.c

@@ -643,6 +643,9 @@ parse_section_main(const char *key, const char *value, struct config *conf,
         conf->title = xstrdup(value);
     }
 
+    else if (strcmp(key, "locked-title") == 0)
+        conf->locked_title = str_to_bool(value);
+
     else if (strcmp(key, "app-id") == 0) {
         free(conf->app_id);
         conf->app_id = xstrdup(value);

config.h

@@ -77,6 +77,7 @@ struct config {
     wchar_t *word_delimiters;
     bool login_shell;
     bool no_wait;
+    bool locked_title;
 
     struct {
         enum conf_size_type type;

doc/foot.ini.5.scd

@@ -224,6 +224,10 @@ in this order:
 *title*
 	Initial window title. Default: _foot_.
 
+*locked-title*
+	Boolean. If enabled, applications are not allowed to change the
+	title at run-time. Default: _no_.
+
 *app-id*
 	Value to set the *app-id* property on the Wayland window to. The
 	compositor can use this value to e.g. group multiple windows, or

foot.ini

@@ -4,6 +4,10 @@
 # term=foot (or xterm-256color if built with -Dterminfo=disabled)
 # login-shell=no
 
+# app-id=foot
+# title=foot
+# locked-title=no
+
 # font=monospace:size=8
 # font-bold=<bold variant of regular font>
 # font-italic=<italic variant of regular font>

terminal.c

@@ -2634,9 +2634,13 @@ term_xcursor_update(struct terminal *term)
 void
 term_set_window_title(struct terminal *term, const char *title)
 {
+    if (term->conf->locked_title && term->window_title_has_been_set)
+        return;
+
     free(term->window_title);
     term->window_title = xstrdup(title);
     render_refresh_title(term);
+    term->window_title_has_been_set = true;
 }
 
 void

terminal.h

@@ -382,6 +382,7 @@ struct terminal {
         bool sixel_cursor_right_of_graphics:1;
     } xtsave;
 
+    bool window_title_has_been_set;
     char *window_title;
     tll(char *) window_title_stack;