Function terminal_bind_arrow

extern/editline/src/terminal.c:1152–1212

terminal_bind_arrow(): * Bind the arrow keys */

 *	Bind the arrow keys
 */
protected void
terminal_bind_arrow(EditLine *el)
{
	el_action_t *map;
	const el_action_t *dmap;
	int i, j;
	char *p;
	funckey_t *arrow = el->el_terminal.t_fkey;

	/* Check if the components needed are initialized */
	if (el->el_terminal.t_buf == NULL || el->el_map.key == NULL)
		return;

	map = el->el_map.type == MAP_VI ? el->el_map.alt : el->el_map.key;
	dmap = el->el_map.type == MAP_VI ? el->el_map.vic : el->el_map.emacs;

	terminal_reset_arrow(el);

	for (i = 0; i < A_K_NKEYS; i++) {
		Char wt_str[VISUAL_WIDTH_MAX];
		Char *px;
		size_t n;

		p = el->el_terminal.t_str[arrow[i].key];
		if (!p || !*p)
			continue;
		for (n = 0; n < VISUAL_WIDTH_MAX && p[n]; ++n)
			wt_str[n] = p[n];
		while (n < VISUAL_WIDTH_MAX)
			wt_str[n++] = '\0';
		px = wt_str;
		j = (unsigned char) *p;
		/*
		 * Assign the arrow keys only if:
		 *
		 * 1. They are multi-character arrow keys and the user
		 *    has not re-assigned the leading character, or
		 *    has re-assigned the leading character to be
		 *	  ED_SEQUENCE_LEAD_IN
		 * 2. They are single arrow keys pointing to an
		 *    unassigned key.
		 */
		if (arrow[i].type == XK_NOD)
			keymacro_clear(el, map, px);
		else {
			if (p[1] && (dmap[j] == map[j] ||
				map[j] == ED_SEQUENCE_LEAD_IN)) {
				keymacro_add(el, px, &arrow[i].fun,
				    arrow[i].type);
				map[j] = ED_SEQUENCE_LEAD_IN;
			} else if (map[j] == ED_UNASSIGNED) {
				keymacro_clear(el, map, px);
				if (arrow[i].type == XK_CMD)
					map[j] = arrow[i].fun.cmd;
				else
					keymacro_add(el, px, &arrow[i].fun,
					    arrow[i].type);
			}