[Emacs-diffs] emacs-25 740849f: Ensure positive number of glyphs for margins of positive width

[Eli Zaretskii]

branch: emacs-25
commit 740849fe986b62a839bce4bbf67d0036fc1be0b9
Author: Eli Zaretskii <address@hidden>
Commit: Eli Zaretskii <address@hidden>

    Ensure positive number of glyphs for margins of positive width
    
    * src/dispnew.c (margin_glyphs_to_reserve): Always return a
    positive value when a non-zero width of the marginal area was
    requested.  (Bug#22356)
---
 src/dispnew.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/src/dispnew.c b/src/dispnew.c
index 8d671f8..3e1557f 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -320,7 +320,9 @@ margin_glyphs_to_reserve (struct window *w, int 
total_glyphs, int margin)
       int width = w->total_cols;
       double d = max (0, margin);
       d = min (width / 2 - 1, d);
-      return (int) ((double) total_glyphs / width * d);
+      /* Since MARGIN is positive, we cannot possibly have less than
+        one glyph for the marginal area.  */
+      return max (1, (int) ((double) total_glyphs / width * d));
     }
   return 0;
 }