small improvement

src/prompt.c

@@ -170,6 +170,10 @@ static void prompt_onKey(ToxWindow *self, Tox *m, wint_t key)
             wmove(self->window, prt->orig_y, X_OFST);
             fetch_hist_item(prt->line, &prt->pos, &prt->len, prt->ln_history, prt->hst_tot,
                             &prt->hst_pos, LN_HIST_MV_UP);
+            if (prt->at_bottom && prt->len >= x2 - X_OFST) {
+                --prt->orig_y;
+                prt->scroll = true;
+            }
         }
     }
 

src/toxic_strings.c

@@ -116,11 +116,16 @@ void fetch_hist_item(wchar_t *buf, size_t *pos, size_t *len, wchar_t (*hst)[MAX_
                      int hst_tot, int *hst_pos, int key_dir)
 {
     if (key_dir == LN_HIST_MV_UP) {
-        if (--(*hst_pos) < 0)
+        if (--(*hst_pos) < 0) {
             ++(*hst_pos);
+            beep();
+            return;
+        }
     } else {
-        if (++(*hst_pos) == hst_tot)
-            --(*hst_pos);
+        if (++(*hst_pos) == hst_tot) {
+            discard_buf(buf, pos, len);
+            return;
+        }
     }
 
     const wchar_t *hst_line = hst[*hst_pos];