Add inline functions to in.h that make the IP4 address tests
a bit easier to read and also add some type safety.

gcc optimizes IP4_ADDR to a constant (O2 or Os)

Signed-off-by: Joe Perches <joe@perches.com

---

 include/linux/in.h |   75 ++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 70 insertions(+), 5 deletions(-)

diff --git a/include/linux/in.h b/include/linux/in.h
index 3975cbf..17d1878 100644
--- a/include/linux/in.h
+++ b/include/linux/in.h
@@ -247,11 +247,76 @@ struct sockaddr_in {
 
 #ifdef __KERNEL__
 /* Some random defines to make it easier in the kernel.. */
-#define LOOPBACK(x)	(((x) & htonl(0xff000000)) == htonl(0x7f000000))
-#define MULTICAST(x)	(((x) & htonl(0xf0000000)) == htonl(0xe0000000))
-#define BADCLASS(x)	(((x) & htonl(0xf0000000)) == htonl(0xf0000000))
-#define ZERONET(x)	(((x) & htonl(0xff000000)) == htonl(0x00000000))
-#define LOCAL_MCAST(x)	(((x) & htonl(0xFFFFFF00)) == htonl(0xE0000000))
+
+static inline __be32 IP4_ADDR(unsigned char a, unsigned char b, unsigned char c, unsigned char d)
+{
+	return htonl((((__u32)(a & 0xff)) << 24) |
+		     (((__u32)(b & 0xff)) << 16) |
+		     (((__u32)(c & 0xff)) << 8) |
+		     (((__u32)(d & 0xff)) << 0));
+}
+
+static inline bool LOOPBACK(__be32 x)
+{
+	return (x & IP4_ADDR(255,0,0,0)) == IP4_ADDR(127,0,0,0);
+}
+
+static inline bool MULTICAST(__be32 x)
+{
+	return (x & IP4_ADDR(240,0,0,0)) == IP4_ADDR(224,0,0,0);
+}
+
+static inline bool BADCLASS(__be32 x)
+{
+	return (x & IP4_ADDR(240,0,0,0)) == IP4_ADDR(240,0,0,0);
+}
+
+static inline bool ZERONET(__be32 x)
+{
+	return (x & IP4_ADDR(255,0,0,0)) == IP4_ADDR(0,0,0,0);
+}
+
+static inline bool LOCAL_MCAST(__be32 x)
+{
+	return (x & IP4_ADDR(255,255,255,0)) == IP4_ADDR(224,0,0,0);
+}
+
+/* Special-Use IPv4 Addresses (RFC3330) */
+
+static inline bool PRIVATE_10(__be32 x)
+{
+	return (x & IP4_ADDR(255,0,0,0)) == IP4_ADDR(10,0,0,0);
+}
+
+static inline bool PRIVATE_172(__be32 x)
+{
+	return (x & ...
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From: Joe Perches <joe@perches.com>

I have no problems with this, but I'd like to add it along
with subsequent patches that use the new routines and
also I'd like to defer this to net-2.6.25 so please resubmit
this later.

Thanks!
-

[ message continues ]

I've since changed the functions in my tree to:

	static inline bool is_ip4_foo(__be32 addr)

and added

	# define FOO(x) is_ip4_foo(x)

which I think makes more sense and allows macro
removal when all current uses are converted.

When you open net-2.6.25, I'll resubmit it.

-

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