Initial version of display/overlay strings is working.

 src/xdisp.c (set_iterator_to_next, get_visually_first_element): Use
 it->bidi_it.string.schars rather than it->string_nchars when
 testing whether we're beyond string end, because string_nchars is
 zero for strings that come from overlays and display properties.
 src/bidi.c (bidi_cache_iterator_state): Fix a bug with testing
 character positions against the cached range, when we use a
 stacked cache.
 src/dispextern.h (struct iterator_stack_entry): New member
 paragraph_embedding.
 src/xdisp.c (push_it, pop_it): Save and restore it.

4 files changed, 23 insertions, 6 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 083aaaaa4b..8d5275f970 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,5 +1,19 @@
 2011-06-25  Eli Zaretskii  <[email protected]>
 
+	* xdisp.c (set_iterator_to_next, get_visually_first_element): Use
+	it->bidi_it.string.schars rather than it->string_nchars when
+	testing whether we're beyond string end, because string_nchars is
+	zero for strings that come from overlays and display properties.
+
+	* bidi.c (bidi_cache_iterator_state): Fix a bug with testing
+	character positions against the cached range, when we use a
+	stacked cache.
+
+	* xdisp.c (push_it, pop_it): Save and restore it.
+
+	* dispextern.h (struct iterator_stack_entry): New member
+	paragraph_embedding.
+
 	* xdisp.c (handle_single_display_spec, next_overlay_string)
 	(get_overlay_strings_1, push_display_prop): Set up the bidi
 	iterator for displaying display or overlay strings.
diff --git a/src/bidi.c b/src/bidi.c
index b518dd4578..0cd8deb47c 100644
--- a/src/bidi.c
+++ b/src/bidi.c
@@ -481,7 +481,7 @@ bidi_cache_iterator_state (struct bidi_it *bidi_it, int resolved)
       if (idx > bidi_cache_start &&
 	  (bidi_it->charpos > (bidi_cache[idx - 1].charpos
 			       + bidi_cache[idx - 1].nchars)
-	   || bidi_it->charpos < bidi_cache[0].charpos))
+	   || bidi_it->charpos < bidi_cache[bidi_cache_start].charpos))
 	{
 	  bidi_cache_reset ();
 	  idx = bidi_cache_start;
diff --git a/src/dispextern.h b/src/dispextern.h
index d5479c7a64..16fa3abdd1 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -2251,6 +2251,7 @@ struct it
     Lisp_Object from_overlay;
     enum glyph_row_area area;
     enum it_method method;
+    bidi_dir_t paragraph_embedding;
     unsigned multibyte_p : 1;
     unsigned string_from_display_prop_p : 1;
     unsigned display_ellipsis_p : 1;
diff --git a/src/xdisp.c b/src/xdisp.c
index dc9a62fc0b..3b93454747 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -5255,6 +5255,7 @@ push_it (struct it *it, struct text_pos *position)
   p->display_ellipsis_p = 0;
   p->line_wrap = it->line_wrap;
   p->bidi_p = it->bidi_p;
+  p->paragraph_embedding = it->paragraph_embedding;
   ++it->sp;
 
   /* Save the state of the bidi iterator as well. */
@@ -5360,6 +5361,7 @@ pop_it (struct it *it)
   it->string_from_display_prop_p = p->string_from_display_prop_p;
   it->line_wrap = p->line_wrap;
   it->bidi_p = p->bidi_p;
+  it->paragraph_embedding = p->paragraph_embedding;
   if (it->bidi_p)
     {
       bidi_pop_it (&it->bidi_it);
@@ -6511,11 +6513,11 @@ set_iterator_to_next (struct it *it, int reseat_p)
     case GET_FROM_C_STRING:
       /* Current display element of IT is from a C string.  */
       if (!it->bidi_p
-	  /* If the string position is beyond string_nchars, it means
+	  /* If the string position is beyond string's end, it means
 	     next_element_from_c_string is padding the string with
 	     blanks, in which case we bypass the bidi iterator,
 	     because it cannot deal with such virtual characters.  */
-	  || IT_CHARPOS (*it) >= it->string_nchars)
+	  || IT_CHARPOS (*it) >= it->bidi_it.string.schars)
 	{
 	  IT_BYTEPOS (*it) += it->len;
 	  IT_CHARPOS (*it) += 1;
@@ -6639,12 +6641,12 @@ set_iterator_to_next (struct it *it, int reseat_p)
       else
 	{
 	  if (!it->bidi_p
-	      /* If the string position is beyond string_nchars, it
+	      /* If the string position is beyond string's end, it
 		 means next_element_from_string is padding the string
 		 with blanks, in which case we bypass the bidi
 		 iterator, because it cannot deal with such virtual
 		 characters.  */
-	      || IT_STRING_CHARPOS (*it) >= it->string_nchars)
+	      || IT_STRING_CHARPOS (*it) >= it->bidi_it.string.schars)
 	    {
 	      IT_STRING_BYTEPOS (*it) += it->len;
 	      IT_STRING_CHARPOS (*it) += 1;
@@ -6779,7 +6781,7 @@ static void
 get_visually_first_element (struct it *it)
 {
   int string_p = STRINGP (it->string) || it->s;
-  EMACS_INT eob = (string_p ? it->string_nchars : ZV);
+  EMACS_INT eob = (string_p ? it->bidi_it.string.schars : ZV);
   EMACS_INT bob = (string_p ? 0 : BEGV);
 
   if (STRINGP (it->string))