X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Futil.h;h=e5339875494842cc1a6638c6cc6b5f6ccb5b8196;hb=e7009c364026d69381cdda23941f99ff040d4948;hp=e741067abd0a0ac9f6e2c5c78005c5082f656822;hpb=71d7c22f54ae32d15133571e09ddf7ab435e8afa;p=openvswitch

diff --git a/lib/util.h b/lib/util.h
index e741067a..e5339875 100644
--- a/lib/util.h
+++ b/lib/util.h
@@ -85,6 +85,22 @@ extern const char *program_name;
 #define OVS_TYPEOF(OBJECT) void *
 #endif
 
+/* Given OBJECT of type pointer-to-structure, expands to the offset of MEMBER
+ * within an instance of the structure.
+ *
+ * The GCC-specific version avoids the technicality of undefined behavior if
+ * OBJECT is null, invalid, or not yet initialized.  This makes some static
+ * checkers (like Coverity) happier.  But the non-GCC version does not actually
+ * dereference any pointer, so it would be surprising for it to cause any
+ * problems in practice.
+ */
+#ifdef __GNUC__
+#define OBJECT_OFFSETOF(OBJECT, MEMBER) offsetof(typeof(*(OBJECT)), MEMBER)
+#else
+#define OBJECT_OFFSETOF(OBJECT, MEMBER) \
+    ((char *) &(OBJECT)->MEMBER - (char *) (OBJECT))
+#endif
+
 /* Given POINTER, the address of the given MEMBER in a STRUCT object, returns
    the STRUCT object. */
 #define CONTAINER_OF(POINTER, STRUCT, MEMBER)                           \
@@ -99,7 +115,7 @@ extern const char *program_name;
  * from the type of '*OBJECT'. */
 #define OBJECT_CONTAINING(POINTER, OBJECT, MEMBER)                      \
     ((OVS_TYPEOF(OBJECT)) (void *)                                      \
-     ((char *) (POINTER) - ((char *) &(OBJECT)->MEMBER - (char *) (OBJECT))))
+     ((char *) (POINTER) - OBJECT_OFFSETOF(OBJECT, MEMBER)))
 
 /* Given POINTER, the address of the given MEMBER within an object of the type
  * that that OBJECT points to, assigns the address of the outer object to
@@ -135,9 +151,13 @@ void *x2nrealloc(void *p, size_t *n, size_t s);
 void ovs_strlcpy(char *dst, const char *src, size_t size);
 void ovs_strzcpy(char *dst, const char *src, size_t size);
 
+void ovs_abort(int err_no, const char *format, ...)
+    PRINTF_FORMAT(2, 3) NO_RETURN;
 void ovs_fatal(int err_no, const char *format, ...)
     PRINTF_FORMAT(2, 3) NO_RETURN;
 void ovs_error(int err_no, const char *format, ...) PRINTF_FORMAT(2, 3);
+void ovs_error_valist(int err_no, const char *format, va_list)
+    PRINTF_FORMAT(2, 0);
 const char *ovs_retval_to_string(int);
 void ovs_hex_dump(FILE *, const void *, size_t, uintptr_t offset, bool ascii);