vim-patch:7.4.562 #2593

Problem:    Segfault with wide screen and error in 'rulerformat'. (Ingo Karkat)
Solution:   Check there is enough space. (Christian Brabandt)

https://github.com/vim/vim/commit/v7-4-562

src/nvim/buffer.c

@@ -3511,6 +3511,11 @@ build_stl_str_hl (
  */
 void get_rel_pos(win_T *wp, char_u *buf, int buflen)
 {
+  // Need at least 3 chars for writing.
+  if (buflen < 3) {
+    return;
+  }
+
   long above;          /* number of lines above window */
   long below;          /* number of lines below window */
 

src/nvim/screen.c

@@ -7106,7 +7106,8 @@ static void win_redr_ruler(win_T *wp, int always)
     if (this_ru_col < (width + 1) / 2)
       this_ru_col = (width + 1) / 2;
     if (this_ru_col + o < width) {
-      while (this_ru_col + o < width) {
+      // Need at least 3 chars left for get_rel_pos() + NUL.
+      while (this_ru_col + o < width && RULER_BUF_LEN > i + 4) {
         if (has_mbyte)
           i += (*mb_char2bytes)(fillchar, buffer + i);
         else

src/nvim/version.c

@@ -221,7 +221,7 @@ static int included_patches[] = {
   565,
   //564 NA
   563,
-  //562,
+  562,
   561,
   //560 NA
   559,