[Python-checkins] python/dist/src/Objects setobject.c,1.38,1.39

[rhettinger@users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Objects
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv6483/Objects

Modified Files:
	setobject.c 
Log Message:
Model set.pop() after dict.popitem().



Index: setobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/setobject.c,v
retrieving revision 1.38
retrieving revision 1.39
diff -u -d -r1.38 -r1.39
--- setobject.c	1 Aug 2005 21:39:28 -0000	1.38
+++ setobject.c	2 Aug 2005 03:45:14 -0000	1.39
@@ -1508,24 +1508,42 @@
 set_pop(PySetObject *so)
 {
 	PyObject *key;
-	int pos = 0;
-	int rv;
+	register setentry *entry;
+	register int i = 0;
 
-	if (!set_next_internal(so, &pos, &key)) {
+	assert (PyAnySet_Check(so));
+	if (so->used == 0) {
 		PyErr_SetString(PyExc_KeyError, "pop from an empty set");
 		return NULL;
 	}
-	Py_INCREF(key);
 
-	rv = set_discard_internal(so, key);
-	if (rv == -1) {
-		Py_DECREF(key);
-		return NULL;
-	} else if (rv == DISCARD_NOTFOUND) {
-		Py_DECREF(key);
-		PyErr_SetObject(PyExc_KeyError, key);
-		return NULL;
+	/* Set entry to "the first" unused or dummy set entry.  We abuse
+	 * the hash field of slot 0 to hold a search finger:
+	 * If slot 0 has a value, use slot 0.
+	 * Else slot 0 is being used to hold a search finger,
+	 * and we use its hash value as the first index to look.
+	 */
+	entry = &so->table[0];
+	if (entry->key == NULL || entry->key == dummy) {
+		i = (int)entry->hash;
+		/* The hash field may be a real hash value, or it may be a
+		 * legit search finger, or it may be a once-legit search
+		 * finger that's out of bounds now because it wrapped around
+		 * or the table shrunk -- simply make sure it's in bounds now.
+		 */
+		if (i > so->mask || i < 1)
+			i = 1;	/* skip slot 0 */
+		while ((entry = &so->table[i])->key == NULL || entry->key==dummy) {
+			i++;
+			if (i > so->mask)
+				i = 1;
+		}
 	}
+	key = entry->key;
+	Py_INCREF(dummy);
+	entry->key = dummy;
+	so->used--;
+	so->table[0].hash = i + 1;  /* next place to start */
 	return key;
 }