A better fix for bug#25845

* src/xdisp.c (font_for_underline_metrics): New function.
* src/dispextern.h: Add its prototype.
* src/xterm.c (x_draw_glyph_string):
* src/w32term.c (x_draw_glyph_string):
* src/nsterm.m (ns_draw_text_decoration): Call it.  This avoids
having identical code 3 times in 3 different files.

1 files changed, 1 insertions, 21 deletions

diff --git a/src/xterm.c b/src/xterm.c
index 57e64c48887..28faea14a3a 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -3636,27 +3636,7 @@ x_draw_glyph_string (struct glyph_string *s)
                 }
               else
                 {
-                  /* If we are drawing in the middle of a glyph row,
-                     find the first glyph in the run of underlined
-                     glyphs preceding the beginning of glyph string S.
-                     This is because that glyph determines the
-                     underline position and thickness for the entire
-                     run of the underlined glyphs.  */
-                  struct glyph *g0 = s->row->glyphs[s->area], *g;
-
-                  for (g = s->first_glyph - 1; g >= g0; g--)
-                    {
-                      struct face *prev_face = FACE_FROM_ID (s->f, g->face_id);
-                      if (!(prev_face && prev_face->underline_p))
-                        break;
-                    }
-
-                  /* Now use the font of the last glyph we saw that
-                     still has the underlined_p flag set.  */
-                  struct face *glyph_face = FACE_FROM_ID (s->f, g[1].face_id);
-                  struct font *font = glyph_face->font;
-                  if (font)
-                    font_prepare_for_face (s->f, glyph_face);
+                  struct font *font = font_for_underline_metrics (s);
 
                   /* Get the underline thickness.  Default is 1 pixel.  */
                   if (font && font->underline_thickness > 0)