Merge commit 'origin/trunk@12184' into fedora

[iptables.git] / trunk / libiptc / linux_stddef.h

diff --git a/trunk/libiptc/linux_stddef.h b/trunk/libiptc/linux_stddef.h
new file mode 100644 (file)
index 0000000..56416f1
--- /dev/null
+++ b/trunk/libiptc/linux_stddef.h
@@ -0,0 +1,39 @@
+#ifndef _LINUX_STDDEF_H
+#define _LINUX_STDDEF_H
+
+#undef NULL
+#if defined(__cplusplus)
+#define NULL 0
+#else
+#define NULL ((void *)0)
+#endif
+
+#undef offsetof
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ *
+ * @ptr:       the pointer to the member.
+ * @type:      the type of the container struct this is embedded in.
+ * @member:    the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({                     \
+        const typeof( ((type *)0)->member ) *__mptr = (ptr);   \
+        (type *)( (char *)__mptr - offsetof(type,member) );})
+
+/*
+ * Check at compile time that something is of a particular type.
+ * Always evaluates to 1 so you may use it easily in comparisons.
+ */
+#define typecheck(type,x) \
+({     type __dummy; \
+       typeof(x) __dummy2; \
+       (void)(&__dummy == &__dummy2); \
+       1; \
+})
+
+
+#endif