Fixes: debbugs:17865

[bpt/emacs.git] / src / font.c

diff --git a/src/font.c b/src/font.c
index fb56b3d..afa1380 100644 (file)
--- a/src/font.c
+++ b/src/font.c
@@ -1,6 +1,6 @@
 /* font.c -- "Font" primitives.
 
-Copyright (C) 2006-2013 Free Software Foundation, Inc.
+Copyright (C) 2006-2014 Free Software Foundation, Inc.
 Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011
   National Institute of Advanced Industrial Science and Technology (AIST)
   Registration Number H13PRO009
@@ -148,7 +148,27 @@ static Lisp_Object font_charset_alist;
    here.  */
 static struct font_driver_list *font_driver_list;
 
-\f
+#ifdef ENABLE_CHECKING
+
+/* Used to catch bogus pointers in font objects.  */
+
+bool
+valid_font_driver (struct font_driver *drv)
+{
+  Lisp_Object tail, frame;
+  struct font_driver_list *fdl;
+
+  for (fdl = font_driver_list; fdl; fdl = fdl->next)
+    if (fdl->driver == drv)
+      return true;
+  FOR_EACH_FRAME (tail, frame)
+    for (fdl = XFRAME (frame)->font_driver_list; fdl; fdl = fdl->next)
+      if (fdl->driver == drv)
+       return true;
+  return false;
+}
+
+#endif /* ENABLE_CHECKING */
 
 /* Creators of font-related Lisp object.  */
 
@@ -187,6 +207,9 @@ font_make_object (int size, Lisp_Object entity, int pixelsize)
     = (struct font *) allocate_pseudovector (size, FONT_OBJECT_MAX, PVEC_FONT);
   int i;
 
+  /* GC can happen before the driver is set up,
+     so avoid dangling pointer here (Bug#17771).  */
+  font->driver = NULL;
   XSETFONT (font_object, font);
 
   if (! NILP (entity))
@@ -2495,7 +2518,7 @@ font_match_p (Lisp_Object spec, Lisp_Object font)
 
    where DRIVER-TYPE is a symbol such as `x', `xft', etc., NUM-FRAMES
    is a number frames sharing this cache, and FONT-CACHE-DATA is a
-   cons (FONT-SPEC FONT-ENTITY ...).  */
+   cons (FONT-SPEC . [FONT-ENTITY ...]).  */
 
 static void font_prepare_cache (struct frame *, struct font_driver *);
 static void font_finish_cache (struct frame *, struct font_driver *);
@@ -2565,18 +2588,21 @@ static void
 font_clear_cache (struct frame *f, Lisp_Object cache, struct font_driver *driver)
 {
   Lisp_Object tail, elt;
-  Lisp_Object tail2, entity;
+  Lisp_Object entity;
+  ptrdiff_t i;
 
   /* CACHE = (DRIVER-TYPE NUM-FRAMES FONT-CACHE-DATA ...) */
   for (tail = XCDR (XCDR (cache)); CONSP (tail); tail = XCDR (tail))
     {
       elt = XCAR (tail);
-      /* elt should have the form (FONT-SPEC FONT-ENTITY ...) */
+      /* elt should have the form (FONT-SPEC . [FONT-ENTITY ...]) */
       if (CONSP (elt) && FONT_SPEC_P (XCAR (elt)))
        {
-         for (tail2 = XCDR (elt); CONSP (tail2); tail2 = XCDR (tail2))
+         elt = XCDR (elt);
+         eassert (VECTORP (elt));
+         for (i = 0; i < ASIZE (elt); i++)
            {
-             entity = XCAR (tail2);
+             entity = AREF (elt, i);
 
              if (FONT_ENTITY_P (entity)
                  && EQ (driver->type, AREF (entity, FONT_TYPE_INDEX)))
@@ -4409,7 +4435,7 @@ where
   LANGSYS is a symbol specifying a langsys tag of OpenType,
   GSUB and GPOS, if non-nil, are lists of symbols specifying feature tags.
 
-If LANGYS is nil, the default langsys is selected.
+If LANGSYS is nil, the default langsys is selected.
 
 The features are applied in the order they appear in the list.  The
 symbol `*' means to apply all available features not present in this
@@ -4765,7 +4791,7 @@ character at index specified by POSITION.  */)
   if (NILP (string))
     {
       if (XBUFFER (w->contents) != current_buffer)
-       error ("Specified window is not displaying the current buffer.");
+       error ("Specified window is not displaying the current buffer");
       CHECK_NUMBER_COERCE_MARKER (position);
       if (! (BEGV <= XINT (position) && XINT (position) < ZV))
        args_out_of_range_3 (position, make_number (BEGV), make_number (ZV));
@@ -4822,6 +4848,21 @@ Type C-l to recover what previously shown.  */)
 }
 #endif
 
+DEFUN ("frame-font-cache", Fframe_font_cache, Sframe_font_cache, 0, 1, 0,
+       doc: /* Return FRAME's font cache.  Mainly used for debugging.
+If FRAME is omitted or nil, use the selected frame.  */)
+  (Lisp_Object frame)
+{
+#ifdef HAVE_WINDOW_SYSTEM
+  struct frame *f = decode_live_frame (frame);
+
+  if (FRAME_WINDOW_P (f))
+    return FRAME_DISPLAY_INFO (f)->name_list_element;
+  else
+#endif
+    return Qnil;
+}
+
 #endif /* FONT_DEBUG */
 
 #ifdef HAVE_WINDOW_SYSTEM
@@ -5114,6 +5155,7 @@ syms_of_font (void)
 #if 0
   defsubr (&Sdraw_string);
 #endif
+  defsubr (&Sframe_font_cache);
 #endif /* FONT_DEBUG */
 #ifdef HAVE_WINDOW_SYSTEM
   defsubr (&Sfont_info);