[Emacs-diffs] emacs/src ChangeLog buffer.c ralloc.c

[Jason Rumney]

CVSROOT:        /sources/emacs
Module name:    emacs
Changes by:     Jason Rumney <jasonr>   08/12/24 11:20:36

Modified files:
        src            : ChangeLog buffer.c ralloc.c 

Log message:
        * ralloc.c (r_alloc_reset_variable): New function.
        
        * buffer.c (Fbuffer_swap_text) [REL_ALLOC]: Reset ralloc's internal
        record of what points where.

CVSWeb URLs:
http://cvs.savannah.gnu.org/viewcvs/emacs/src/ChangeLog?cvsroot=emacs&r1=1.7224&r2=1.7225
http://cvs.savannah.gnu.org/viewcvs/emacs/src/buffer.c?cvsroot=emacs&r1=1.576&r2=1.577
http://cvs.savannah.gnu.org/viewcvs/emacs/src/ralloc.c?cvsroot=emacs&r1=1.69&r2=1.70

Patches:
Index: ChangeLog
===================================================================
RCS file: /sources/emacs/emacs/src/ChangeLog,v
retrieving revision 1.7224
retrieving revision 1.7225
diff -u -b -r1.7224 -r1.7225
--- ChangeLog   22 Dec 2008 20:45:52 -0000      1.7224
+++ ChangeLog   24 Dec 2008 11:20:32 -0000      1.7225
@@ -1,3 +1,10 @@
+2008-12-24  Jason Rumney  <address@hidden>
+
+       * ralloc.c (r_alloc_reset_variable): New function.
+
+       * buffer.c (Fbuffer_swap_text) [REL_ALLOC]: Reset ralloc's internal
+       record of what points where.
+
 2008-12-22  Dan Nicolaescu  <address@hidden>
 
        * minibuf.c (read_minibuf): Follow the non-interactive case when

Index: buffer.c
===================================================================
RCS file: /sources/emacs/emacs/src/buffer.c,v
retrieving revision 1.576
retrieving revision 1.577
diff -u -b -r1.576 -r1.577
--- buffer.c    22 Dec 2008 09:48:22 -0000      1.576
+++ buffer.c    24 Dec 2008 11:20:35 -0000      1.577
@@ -2182,6 +2182,10 @@
   return byte_pos;
 }
 
+#ifdef REL_ALLOC
+extern void r_alloc_reset_variable P_ ((PTR *, PTR *));
+#endif /* REL_ALLOC */
+
 DEFUN ("buffer-swap-text", Fbuffer_swap_text, Sbuffer_swap_text,
        1, 1, 0,
        doc: /* Swap the text between current buffer and BUFFER.  */)
@@ -2223,6 +2227,13 @@
   swapfield (own_text, struct buffer_text);
   eassert (current_buffer->text == &current_buffer->own_text);
   eassert (other_buffer->text == &other_buffer->own_text);
+#ifdef REL_ALLOC
+  r_alloc_reset_variable ((PTR *) &current_buffer->own_text.beg,
+                         (PTR *) &other_buffer->own_text.beg);
+  r_alloc_reset_variable ((PTR *) &other_buffer->own_text.beg,
+                         (PTR *) &current_buffer->own_text.beg);
+#endif /* REL_ALLOC */
+
   swapfield (pt, EMACS_INT);
   swapfield (pt_byte, EMACS_INT);
   swapfield (begv, EMACS_INT);

Index: ralloc.c
===================================================================
RCS file: /sources/emacs/emacs/src/ralloc.c,v
retrieving revision 1.69
retrieving revision 1.70
diff -u -b -r1.69 -r1.70
--- ralloc.c    21 Nov 2008 12:14:07 -0000      1.69
+++ ralloc.c    24 Dec 2008 11:20:36 -0000      1.70
@@ -1223,6 +1223,34 @@
 
 #endif /* DEBUG */
 
+/* Update the internal record of which variable points to some data to NEW.
+   Used by buffer-swap-text in Emacs to restore consistency after it
+   swaps the buffer text between two buffer objects.  The OLD pointer
+   is checked to ensure that memory corruption does not occur due to
+   misuse.  */
+void
+r_alloc_reset_variable (old, new)
+     POINTER *old, *new;
+{
+  bloc_ptr bloc = first_bloc;
+
+  /* Find the bloc that corresponds to the data pointed to by pointer.
+     find_bloc cannot be used, as it has internal consistency checks
+     which fail when the variable needs reseting.  */
+  while (bloc != NIL_BLOC)
+    {
+      if (bloc->data == *new)
+       break;
+
+      bloc = bloc->next;
+    }
+
+  if (bloc == NIL_BLOC || bloc->variable != old)
+    abort ();
+
+  /* Update variable to point to the new location.  */
+  bloc->variable = new;
+}
 
 
 /***********************************************************************