Perform font-specific cleanup when font object is swept by GC. See

http://lists.gnu.org/archive/html/emacs-devel/2013-10/msg00740.html.
* alloc.c (cleanup_vector): New function.
(sweep_vector): Call it for each reclaimed vector object.
* font.h (struct font): Adjust comment.

3 files changed, 25 insertions, 4 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index cd31196a15a..6111e83e801 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -9,9 +9,15 @@
         * nsfont.m (nsfont_close):
         * w32font.c (w32font_close):
         * xfont.c (xfont_close):
-        * xftfont.c (xftfont_close): Adjust driver-specific close
-        functions, tweak comments and make functions safe if called
-        more than once for the same font object.
+        * xftfont.c (xftfont_close): Adjust driver-specific close functions,
+        tweak comments and make functions safe if called more than once for
+        the same font object.
+
+        Perform font-specific cleanup when font object is swept by GC.  See
+        http://lists.gnu.org/archive/html/emacs-devel/2013-10/msg00740.html.
+        * alloc.c (cleanup_vector): New function.
+        (sweep_vector): Call it for each reclaimed vector object.
+        * font.h (struct font): Adjust comment.
 
 2013-10-24  Glenn Morris  <rgm@gnu.org>
 
diff --git a/src/alloc.c b/src/alloc.c
index a65dbb48b93..f57e22d9cc0 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -2837,6 +2837,19 @@ vector_nbytes (struct Lisp_Vector *v)
   return vroundup (size);
 }
 
+/* Release extra resources still in use by VECTOR, which may be any
+   vector-like object.  For now, this is used just to free data in
+   font objects.  */
+
+static void
+cleanup_vector (struct Lisp_Vector *vector)
+{
+  if (PSEUDOVECTOR_TYPEP (&vector->header, PVEC_FONT)
+      && ((vector->header.size & PSEUDOVECTOR_SIZE_MASK)
+          == FONT_OBJECT_MAX))
+    ((struct font *) vector)->driver->close ((struct font *) vector);
+}
+
 /* Reclaim space used by unmarked vectors.  */
 
 static void
@@ -2871,6 +2884,7 @@ sweep_vectors (void)
             {
               ptrdiff_t total_bytes;
 
+              cleanup_vector (vector);
               nbytes = vector_nbytes (vector);
               total_bytes = nbytes;
               next = ADVANCE (vector, nbytes);
@@ -2882,6 +2896,7 @@ sweep_vectors (void)
                 {
                   if (VECTOR_MARKED_P (next))
                     break;
+                  cleanup_vector (next);
                   nbytes = vector_nbytes (next);
                   total_bytes += nbytes;
                   next = ADVANCE (next, nbytes);
diff --git a/src/font.h b/src/font.h
index 9285330ce54..2db8d35af48 100644
--- a/src/font.h
+++ b/src/font.h
@@ -545,7 +545,7 @@ struct font_driver
   Lisp_Object (*open) (struct frame *f, Lisp_Object font_entity,
                        int pixel_size);
 
-  /* Close FONT.  */
+  /* Close FONT.  NOTE: this can be called by GC.  */
   void (*close) (struct font *font);
 
   /* Optional (if FACE->extra is not used).