(handle_auto_composed_prop): Simplify the code. Never

return HANDLED_RECOMPUTE_PROPS.

1 files changed, 69 insertions, 65 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 8ae136c9f75..e120a8fa5a7 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -4554,50 +4554,87 @@ handle_auto_composed_prop (it)
   if (FUNCTIONP (Vauto_composition_function))
     {
       Lisp_Object val;
-      EMACS_INT pos, this_pos;
+      EMACS_INT pos, pos_byte, this_pos, start, end;
+      int c;
 
       if (STRINGP (it->string))
-        pos = IT_STRING_CHARPOS (*it);
+        {
+          const unsigned char *s;
+
+          pos = IT_STRING_CHARPOS (*it);
+          pos_byte = IT_STRING_BYTEPOS (*it);
+          s = SDATA (it->string) + pos_byte;
+          if (STRING_MULTIBYTE (it->string))
+            c = STRING_CHAR (s, 0);
+          else
+            c = *s;
+        }
       else
-        pos = IT_CHARPOS (*it);
+        {
+          pos = IT_CHARPOS (*it);
+          pos_byte = IT_BYTEPOS (*it);
+          c = FETCH_CHAR (pos_byte);
+        }
       this_pos = pos;
 
-      val =Fget_char_property (make_number (pos), Qauto_composed, it->string);
-      if (! NILP (val))
+      if (get_property_and_range (pos, Qauto_composed, &val, &start, &end,
+                                  it->string))
         {
-          Lisp_Object limit = Qnil, next;
-          
-          /* As Fnext_single_char_property_change is very slow, we
-             limit the search to the current line.  */
-          if (STRINGP (it->string))
-            limit = make_number (SCHARS (it->string));
-          else
-            limit = make_number (find_next_newline_no_quit (pos, 1));
+          Lisp_Object cmp_prop;
+          EMACS_INT cmp_start, cmp_end;
 
-          next = (Fnext_single_property_change
-                  (make_number (pos), Qauto_composed, it->string, limit));
-          if (XINT (next) < XINT (limit))
+#ifdef USE_FONT_BACKEND
+          if (enable_font_backend
+              && get_property_and_range (pos, Qcomposition, &cmp_prop,
+                                         &cmp_start, &cmp_end, it->string)
+              && cmp_start == pos
+              && COMPOSITION_METHOD (cmp_prop) == COMPOSITION_WITH_GLYPH_STRING)
             {
-              /* The current point is auto-composed, but there exist
-                 characters not yet composed beyond the auto-composed
-                 region.  There's a possiblity that the last
-                 characters in the region may be newly composed.  */
-              int charpos = XINT (next) - 1, bytepos, c;
+              Lisp_Object gstring = COMPOSITION_COMPONENTS (cmp_prop);
+              Lisp_Object font_object = LGSTRING_FONT (gstring);
+
+              if (! EQ (font_object,
+                        font_at (c, pos, FACE_FROM_ID (it->f, it->face_id),
+                                 it->w, it->string)))
+                /* We must re-compute the composition.  */
+                val = Qnil;
+            }
+#endif
+          if (! NILP (val))
+            {
+              EMACS_INT limit;
 
+              /* As Fnext_single_char_property_change is very slow, we
+                 limit the search to the current line.  */
               if (STRINGP (it->string))
-                {
-                  bytepos = string_char_to_byte (it->string, charpos);
-                  c = SDATA (it->string)[bytepos];
-                }
+                limit = SCHARS (it->string);
               else
+                limit = find_next_newline_no_quit (pos, 1);
+
+              if (end < limit)
                 {
-                  bytepos = CHAR_TO_BYTE (charpos);
-                  c = FETCH_BYTE (bytepos);
+                  /* The current point is auto-composed, but there
+                     exist characters not yet composed beyond the
+                     auto-composed region.  There's a possiblity that
+                     the last characters in the region may be newly
+                     composed.  */
+                  int charpos = end - 1, bytepos, c;
+
+                  if (STRINGP (it->string))
+                    {
+                      bytepos = string_char_to_byte (it->string, charpos);
+                      c = SDATA (it->string)[bytepos];
+                    }
+                  else
+                    {
+                      bytepos = CHAR_TO_BYTE (charpos);
+                      c = FETCH_BYTE (bytepos);
+                    }
+                  if (c != '\n')
+                    /* If the last character is not newline, it may be
+                       composed with the following characters.  */
+                    val = Qnil, pos = charpos + 1;
                 }
-              if (c != '\n')
-                /* If the last character is not newline, it may be
-                   composed with the following characters.  */
-                val = Qnil, pos = charpos + 1;
             }
         }
       if (NILP (val))
@@ -4611,45 +4648,12 @@ handle_auto_composed_prop (it)
           args[2] = it->string;
 #ifdef USE_FONT_BACKEND
           if (enable_font_backend)
-            {
-              struct face *face = FACE_FROM_ID (it->f, it->face_id);
-              int c;
-
-              if (STRINGP (it->string))
-                {
-                  EMACS_INT pos_byte = IT_STRING_BYTEPOS (*it);
-                  const unsigned char *s = SDATA (it->string) + pos_byte;
-
-                  if (STRING_MULTIBYTE (it->string))
-                    it->c = STRING_CHAR (s, 0);
-                  else
-                    it->c = *s;
-                }
-              else
-                {
-                  EMACS_INT pos_byte = IT_BYTEPOS (*it);
-
-                  it->c = FETCH_CHAR (pos_byte);
-                }
-              args[3] = it->window;
-            }
+            args[3] = it->window;
           else
 #endif  /* USE_FONT_BACKEND */
             args[3] = Qnil;
           safe_call (4, args);
           unbind_to (count, Qnil);
-
-          if (this_pos == pos)
-            {
-              val = Fget_char_property (args[1], Qauto_composed, it->string);
-              /* Return HANDLED_RECOMPUTE_PROPS only if function composed
-                 something.  This avoids an endless loop if they failed to
-                 fontify the text for which reason ever.  */
-              if (! NILP (val))
-                handled = HANDLED_RECOMPUTE_PROPS;
-            }
-          else
-            handled = HANDLED_RECOMPUTE_PROPS;
         }
     }