(produce_glyphs): Handle IT_STRETCH.

(produce_stretch_glyph): New function to handle space width and
align-to display properties on non-window systems.

1 files changed, 87 insertions, 1 deletions

diff --git a/src/term.c b/src/term.c
index 317318eb8bf..dc0e51cdf81 100644
--- a/src/term.c
+++ b/src/term.c
@@ -79,6 +79,10 @@ static void tty_hide_cursor P_ ((void));
 
 #define OUTPUT1_IF(a) do { if (a) tputs (a, 1, cmputc); } while (0)
 
+/* Display space properties */
+
+extern Lisp_Object Qspace, QCalign_to, QCwidth;
+
 /* Function to use to ring the bell.  */
 
 Lisp_Object Vring_bell_function;
@@ -1595,6 +1599,7 @@ term_get_fkeys_1 ()
  ***********************************************************************/
 
 static void append_glyph P_ ((struct it *));
+static void produce_stretch_glyph P_ ((struct it *));
 
 
 /* Append glyphs to IT's glyph_row.  Called from produce_glyphs for
@@ -1658,9 +1663,14 @@ produce_glyphs (it)
   /* If a hook is installed, let it do the work.  */
   xassert (it->what == IT_CHARACTER
            || it->what == IT_COMPOSITION
-           || it->what == IT_IMAGE
            || it->what == IT_STRETCH);
 
+  if (it->what == IT_STRETCH)
+    {
+      produce_stretch_glyph (it);
+      goto done;
+    }
+
   /* Nothing but characters are supported on terminal frames.  For a
      composition sequence, it->c is the first character of the
      sequence.  */
@@ -1734,6 +1744,7 @@ produce_glyphs (it)
         append_glyph (it);
     }
 
+ done:
   /* Advance current_x by the pixel width as a convenience for
      the caller.  */
   if (it->area == TEXT_AREA)
@@ -1743,6 +1754,81 @@ produce_glyphs (it)
 }
 
 
+/* Produce a stretch glyph for iterator IT.  IT->object is the value
+   of the glyph property displayed.  The value must be a list
+   `(space KEYWORD VALUE ...)' with the following KEYWORD/VALUE pairs
+   being recognized:
+
+   1. `:width WIDTH' specifies that the space should be WIDTH *
+   canonical char width wide.  WIDTH may be an integer or floating
+   point number.
+
+   2. `:align-to HPOS' specifies that the space should be wide enough
+   to reach HPOS, a value in canonical character units.  */
+
+static void
+produce_stretch_glyph (it)
+     struct it *it;
+{
+  /* (space :width WIDTH ...)  */
+  Lisp_Object prop, plist;
+  int width = 0, align_to = -1;
+  int zero_width_ok_p = 0;
+  double tem;
+
+  /* List should start with `space'.  */
+  xassert (CONSP (it->object) && EQ (XCAR (it->object), Qspace));
+  plist = XCDR (it->object);
+
+  /* Compute the width of the stretch.  */
+  if ((prop = Fplist_get (plist, QCwidth), !NILP (prop))
+      && calc_pixel_width_or_height (&tem, it, prop, 0, 1, 0))
+    {
+      /* Absolute width `:width WIDTH' specified and valid.  */
+      zero_width_ok_p = 1;
+      width = (int)(tem + 0.5);
+    }
+  else if ((prop = Fplist_get (plist, QCalign_to), !NILP (prop))
+           && calc_pixel_width_or_height (&tem, it, prop, 0, 1, &align_to))
+    {
+      if (it->glyph_row == NULL || !it->glyph_row->mode_line_p)
+        align_to = (align_to < 0 
+                    ? 0
+                    : align_to - window_box_left_offset (it->w, TEXT_AREA));
+      else if (align_to < 0)
+        align_to = window_box_left_offset (it->w, TEXT_AREA);
+      width = max (0, (int)(tem + 0.5) + align_to - it->current_x);
+      zero_width_ok_p = 1;
+    }
+  else
+    /* Nothing specified -> width defaults to canonical char width.  */
+    width = FRAME_COLUMN_WIDTH (it->f);
+
+  if (width <= 0 && (width < 0 || !zero_width_ok_p))
+    width = 1;
+
+  if (width > 0 && it->glyph_row)
+    {
+      Lisp_Object o_object = it->object;
+      Lisp_Object object = it->stack[it->sp - 1].string;
+      int n = width;
+      int c = it->c;
+
+      if (!STRINGP (object))
+        object = it->w->buffer;
+      it->object = object;
+      it->c = ' ';
+      it->pixel_width = it->len = 1;
+      while (n--)
+        append_glyph (it);
+      it->object = o_object;
+      it->c = c;
+    }
+  it->pixel_width = width;
+  it->nglyphs = width;
+}
+
+
 /* Get information about special display element WHAT in an
    environment described by IT.  WHAT is one of IT_TRUNCATION or
    IT_CONTINUATION.  Maybe produce glyphs for WHAT if IT has a