Fix and document display of glyphless characters.

 src/xdisp.c (set_cursor_from_row): Fix cursor positioning on
 zero-width characters.
 (syms_of_xdisp) <glyphless-char-display>: Doc fix.
 src/.gdbinit (pgx): Adapt to latest changes in `struct glyph'.
 src/w32term.c (x_draw_glyphless_glyph_string_foreground): Draw the
 box before drawing the glyphs inside it.
 src/dispextern.h (enum glyphless_display_method): Rename
 GLYPHLESS_DISPLAY_HEXA_CODE to GLYPHLESS_DISPLAY_HEX_CODE.  All
 users changed.
 src/term.c (append_glyphless_glyph, produce_glyphless_glyph): Fix
 comments.
 (produce_glyphless_glyph): Enclose "U+nnnn" and "empty box"
 whitespace in "[]", to simulate a box.  Don't use uninitialized
 variable `width'.
 lisp/international/characters.el (glyphless-char-display-control):
 Renamed from glyphless-char-control; all users changed.  Doc fix.
 Signal an error if display method is not one of the recognized
 symbols.
 doc/emacs/rmail.texi (Rmail Coding): Characters with no fonts are not
 necessarily displayed as empty boxes.
 doc/emacs/mule.texi (Language Environments, Fontsets): Characters with no
 fonts are not necessarily displayed as empty boxes.
 doc/emacs/display.texi (Text Display): Document display of glyphless
 characters.
 doc/lispref/display.texi (Usual Display): Characters with no fonts are not
 necessarily displayed as empty boxes.
 etc/NEWS: Document display of glyphless characters.

1 files changed, 7 insertions, 7 deletions

diff --git a/src/w32term.c b/src/w32term.c
index a93bc064c39..33b60c568c0 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -1440,7 +1440,7 @@ x_draw_glyphless_glyph_string_foreground (struct glyph_string *s)
                 str = (char *) SDATA (acronym);
             }
         }
-      else if (glyph->u.glyphless.method == GLYPHLESS_DISPLAY_HEXA_CODE)
+      else if (glyph->u.glyphless.method == GLYPHLESS_DISPLAY_HEX_CODE)
         {
           sprintf ((char *) buf, "%0*X",
                    glyph->u.glyphless.ch < 0x10000 ? 4 : 6,
@@ -1448,6 +1448,11 @@ x_draw_glyphless_glyph_string_foreground (struct glyph_string *s)
           str = buf;
         }
 
+      if (glyph->u.glyphless.method != GLYPHLESS_DISPLAY_THIN_SPACE)
+        w32_draw_rectangle (s->hdc, s->gc,
+                            x, s->ybase - glyph->ascent,
+                            glyph->pixel_width - 1,
+                            glyph->ascent + glyph->descent - 1);
       if (str)
         {
           struct font *font = s->font;
@@ -1456,7 +1461,7 @@ x_draw_glyphless_glyph_string_foreground (struct glyph_string *s)
           HFONT old_font;
 
           old_font = SelectObject (s->hdc, FONT_HANDLE (font));
-          /* It is assured that all LEN characters in STR is ASCII.  */
+          /* It is certain that all LEN characters in STR are ASCII.  */
           for (j = 0; j < len; j++)
             {
               code = font->driver->encode_char (font, str[j]);
@@ -1472,11 +1477,6 @@ x_draw_glyphless_glyph_string_foreground (struct glyph_string *s)
                               with_background);
           SelectObject (s->hdc, old_font);
         }
-      if (glyph->u.glyphless.method != GLYPHLESS_DISPLAY_THIN_SPACE)
-        w32_draw_rectangle (s->hdc, s->gc,
-                            x, s->ybase - glyph->ascent,
-                            glyph->pixel_width - 1,
-                            glyph->ascent + glyph->descent - 1);
       x += glyph->pixel_width;
    }
 }