Remove Py_INCREF and Py_DECREF for objects in doubly linked list.

The cache is intended to keep weak references to objects.  An object
should be deallocated when the only references to it are in the
cache.  If an object is unghostified and added to the list of live
objects, the list should have a borrowed reference.  Otherwise, the
cache will keep the object alive after all other references have
disappeared.

src/Persistence/cPersistence.c

@@ -14,7 +14,7 @@
 static char cPersistence_doc_string[] = 
 "Defines Persistent mixin class for persistent objects.\n"
 "\n"
-"$Id: cPersistence.c,v 1.66 2003/04/01 16:08:14 jeremy Exp $\n";
+"$Id: cPersistence.c,v 1.67 2003/04/01 17:33:23 jeremy Exp $\n";
 
 #include "cPersistence.h"
 
@@ -131,7 +131,6 @@ unghostify(cPersistentObject *self)
             self->ring.prev = home->prev;
 	    home->prev->next = &self->ring;
 	    home->prev = &self->ring;
-            Py_INCREF(self);
         }
         self->state = cPersistent_CHANGED_STATE;
         /* Call the object's __setstate__() */
@@ -185,14 +184,6 @@ ghostify(cPersistentObject *self)
     self->ring.prev = NULL;
     self->ring.next = NULL;
     self->state = cPersistent_GHOST_STATE;
-
-    /* We remove the reference to the just ghosted object that the ring
-     * holds.  Note that the dictionary of oids->objects has an uncounted
-     * reference, so if the ring's reference was the only one, this frees
-     * the ghost object.  Note further that the object's dealloc knows to
-     * inform the dictionary that it is going away.
-     */
-    Py_DECREF(self);
 }
 
 static void

src/ZODB/cPersistence.c

@@ -14,7 +14,7 @@
 static char cPersistence_doc_string[] = 
 "Defines Persistent mixin class for persistent objects.\n"
 "\n"
-"$Id: cPersistence.c,v 1.66 2003/04/01 16:08:14 jeremy Exp $\n";
+"$Id: cPersistence.c,v 1.67 2003/04/01 17:33:23 jeremy Exp $\n";
 
 #include "cPersistence.h"
 
@@ -131,7 +131,6 @@ unghostify(cPersistentObject *self)
             self->ring.prev = home->prev;
 	    home->prev->next = &self->ring;
 	    home->prev = &self->ring;
-            Py_INCREF(self);
         }
         self->state = cPersistent_CHANGED_STATE;
         /* Call the object's __setstate__() */
@@ -185,14 +184,6 @@ ghostify(cPersistentObject *self)
     self->ring.prev = NULL;
     self->ring.next = NULL;
     self->state = cPersistent_GHOST_STATE;
-
-    /* We remove the reference to the just ghosted object that the ring
-     * holds.  Note that the dictionary of oids->objects has an uncounted
-     * reference, so if the ring's reference was the only one, this frees
-     * the ghost object.  Note further that the object's dealloc knows to
-     * inform the dictionary that it is going away.
-     */
-    Py_DECREF(self);
 }
 
 static void

src/persistent/cPersistence.c

@@ -14,7 +14,7 @@
 static char cPersistence_doc_string[] = 
 "Defines Persistent mixin class for persistent objects.\n"
 "\n"
-"$Id: cPersistence.c,v 1.66 2003/04/01 16:08:14 jeremy Exp $\n";
+"$Id: cPersistence.c,v 1.67 2003/04/01 17:33:23 jeremy Exp $\n";
 
 #include "cPersistence.h"
 
@@ -131,7 +131,6 @@ unghostify(cPersistentObject *self)
             self->ring.prev = home->prev;
 	    home->prev->next = &self->ring;
 	    home->prev = &self->ring;
-            Py_INCREF(self);
         }
         self->state = cPersistent_CHANGED_STATE;
         /* Call the object's __setstate__() */
@@ -185,14 +184,6 @@ ghostify(cPersistentObject *self)
     self->ring.prev = NULL;
     self->ring.next = NULL;
     self->state = cPersistent_GHOST_STATE;
-
-    /* We remove the reference to the just ghosted object that the ring
-     * holds.  Note that the dictionary of oids->objects has an uncounted
-     * reference, so if the ring's reference was the only one, this frees
-     * the ghost object.  Note further that the object's dealloc knows to
-     * inform the dictionary that it is going away.
-     */
-    Py_DECREF(self);
 }
 
 static void