input: ignore modifiers on a VT while executing a macro or a string bind

Any modifier keys that are needed to start the execution of a macro
(or of a string bind) should not affect the interpretation of the
keystrokes that are contained within the macro or the string.

This fixes https://savannah.gnu.org/bugs/?57660.

Bug existed since macros were introduced, in version 2.9.0.

src/global.c

@@ -40,8 +40,11 @@ bool meta_key;
 		/* Whether the current keystroke is a Meta key. */
 bool shift_held;
 		/* Whether Shift was being held together with a movement key. */
+bool mute_modifiers = FALSE;
+		/* Whether to ignore modifier keys while running a macro or string bind. */
 bool bracketed_paste = FALSE;
 		/* Whether text is being pasted into nano from outside. */
+
 bool focusing = TRUE;
 		/* Whether an update of the edit window should center the cursor. */
 

src/nano.c

@@ -2570,6 +2570,10 @@ int main(int argc, char **argv)
 	while (TRUE) {
 #ifdef ENABLE_LINENUMBERS
 		confirm_margin();
+#endif
+#ifdef __linux__
+		if (on_a_vt && get_key_buffer_len() == 0)
+			mute_modifiers = FALSE;
 #endif
 		if (currmenu != MMAIN)
 			bottombars(MMAIN);

src/proto.h

@@ -31,6 +31,7 @@ extern bool shifted_metas;
 
 extern bool meta_key;
 extern bool shift_held;
+extern bool mute_modifiers;
 extern bool bracketed_paste;
 
 extern bool focusing;

src/winio.c

@@ -115,6 +115,8 @@ void run_macro(void)
 
 	for (i = 0; i < macro_length; i++)
 		key_buffer[i] = macro_buffer[i];
+
+	mute_modifiers = TRUE;
 }
 #endif /* !NANO_TINY */
 
@@ -284,6 +286,8 @@ void implant(const char *string)
 {
 	for (int i = strlen(string); i > 0; i--)
 		put_back((unsigned char)string[i - 1]);
+
+	mute_modifiers = TRUE;
 }
 #endif
 
@@ -586,7 +590,7 @@ int parse_kbinput(WINDOW *win)
 	unsigned char modifiers = 6;
 
 	/* Modifiers are: Alt (8), Ctrl (4), Shift (1). */
-	if (on_a_vt && ioctl(0, TIOCLINUX, &modifiers) >= 0) {
+	if (on_a_vt && !mute_modifiers && ioctl(0, TIOCLINUX, &modifiers) >= 0) {
 #ifndef NANO_TINY
 		/* Is Delete pressed together with Shift or Shift+Ctrl? */
 		if (retval == KEY_DC) {