From: Ben Pfaff <blp@cs.stanford.edu>
Date: Thu, 28 Sep 2006 12:36:41 +0000 (+0000)
Subject: Make list_entry, hash_entry more type-safe.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?p=pintos-anon;a=commitdiff_plain;h=f294e7e618e110f8203ea7cf800acb2e1334774b

Make list_entry, hash_entry more type-safe.
Suggestion from Godmar Back.
---

diff --git a/src/lib/kernel/hash.h b/src/lib/kernel/hash.h
index 3f2e43c..db9f674 100644
--- a/src/lib/kernel/hash.h
+++ b/src/lib/kernel/hash.h
@@ -36,8 +36,9 @@ struct hash_elem
    name of the outer structure STRUCT and the member name MEMBER
    of the hash element.  See the big comment at the top of the
    file for an example. */
-#define hash_entry(HASH_ELEM, STRUCT, MEMBER)                              \
-        ((STRUCT *) ((uint8_t *) (HASH_ELEM) - offsetof (STRUCT, MEMBER)))
+#define hash_entry(HASH_ELEM, STRUCT, MEMBER)                   \
+        ((STRUCT *) ((uint8_t *) &(HASH_ELEM)->list_elem        \
+                     - offsetof (STRUCT, MEMBER.list_elem)))
 
 /* Computes and returns the hash value for hash element E, given
    auxiliary data AUX. */
diff --git a/src/lib/kernel/list.h b/src/lib/kernel/list.h
index a041299..2388f9a 100644
--- a/src/lib/kernel/list.h
+++ b/src/lib/kernel/list.h
@@ -105,8 +105,9 @@ struct list
    name of the outer structure STRUCT and the member name MEMBER
    of the list element.  See the big comment at the top of the
    file for an example. */
-#define list_entry(LIST_ELEM, STRUCT, MEMBER)                              \
-        ((STRUCT *) ((uint8_t *) (LIST_ELEM) - offsetof (STRUCT, MEMBER)))
+#define list_entry(LIST_ELEM, STRUCT, MEMBER)           \
+        ((STRUCT *) ((uint8_t *) &(LIST_ELEM)->next     \
+                     - offsetof (STRUCT, MEMBER.next)))
 
 void list_init (struct list *);