csi: implement REP - CSI Ps b

csi.c

@@ -324,6 +324,22 @@ csi_dispatch(struct terminal *term, uint8_t final)
     switch (term->vt.private[0]) {
     case 0: {
         switch (final) {
+        case 'b':
+            if (term->vt.last_printed != 0) {
+                /*
+                 * Note: we never reset 'last-printed'. According to
+                 * ECMA-48, the behaviour is undefined if REP was
+                 * _not_ preceeded by a graphical character.
+                 */
+                int count = vt_param_get(term, 0, 1);
+                LOG_DBG("REP: '%C' %d times", term->vt.last_printed, count);
+
+                const int width = wcwidth(term->vt.last_printed);
+                for (int i = 0; i < count; i++)
+                    term_print(term, term->vt.last_printed, width);
+            }
+            break;
+
         case 'c': {
             /* Send Device Attributes (Primary DA) */
 

foot.info

@@ -211,6 +211,7 @@ foot+base|foot base fragment,
     kri=\E[1;2A,
     op=\E[39;49m,
     rc=\E8,
+    rep=%p1%c\E[%p2%{1}%-%db,
     rev=\E[7m,
     ri=\EM,
     rin=\E[%p1%dT,

terminal.h

@@ -110,6 +110,7 @@ struct vt_param {
 
 struct vt {
     int state;  /* enum state */
+    wchar_t last_printed;
     struct {
         struct vt_param v[16];
         size_t idx;