[patch] byteorder.h, ntohl, and compiling userspace programs

Dan Kegel
2002-05-31T07:14:33Z

[-- Attachment #1: Type: text/plain, Size: 903 bytes --]

On 5/14, I wrote:
> Dimi Shahbaz wrote:
> > I'm trying to build glibc ...
> > [but get a compile error:]
> > ../inet/netinet/in.h:259: parse error before '(' token
> > [caused by linux's #define of ntohl when compiling glibc's
> > function prototype for ntohl]
>
> I think the conflict is with the ntohl macros defined in
> /usr/src/linux/include/linux/byteorder/generic.h
>
> These days, I don't see why the Linux kernel headers
> should be defining ntohl for userspace; libc's headers
> do that. So how about simplifying generic.h so it
> only does anything when compiling the kernel:

Here's that patch again (MIME this time, so tabs don't get
lost by my silly gui mailer); applies cleanly against against 2.4.19-pre8.
Nobody commented on it last time I posted it, and it does
make compiling gcc easier, so I guess that makes it trivial patch
monkey fodder. Or am I making a silly mistake?
- Dan

[-- Attachment #2: htonl.patch --]
[-- Type: text/plain, Size: 1405 bytes --]

--- linux/include/linux/byteorder/generic.h.orig Tue May 14 10:02:49 2002
+++ linux/include/linux/byteorder/generic.h Tue May 14 10:06:48 2002
@@ -123,6 +123,7 @@
#endif

+#if defined(__KERNEL__)
/*
* Handle ntohl and suches. These have various compatibility
* issues - like we want to give the prototype even though we
@@ -146,17 +147,11 @@
* Do the prototypes. Somebody might want to take the
* address or some such sick thing..
*/
-#if defined(__KERNEL__) || (defined (__GLIBC__) && __GLIBC__ >= 2)
extern __u32 ntohl(__u32);
extern __u32 htonl(__u32);
-#else
-extern unsigned long int ntohl(unsigned long int);
-extern unsigned long int htonl(unsigned long int);
-#endif
extern unsigned short int ntohs(unsigned short int);
extern unsigned short int htons(unsigned short int);

-
#if defined(__GNUC__) && (__GNUC__ >= 2) && defined(__OPTIMIZE__)

#define ___htonl(x) __cpu_to_be32(x)
@@ -164,17 +159,14 @@
#define ___ntohl(x) __be32_to_cpu(x)
#define ___ntohs(x) __be16_to_cpu(x)

-#if defined(__KERNEL__) || (defined (__GLIBC__) && __GLIBC__ >= 2)
#define htonl(x) ___htonl(x)
#define ntohl(x) ___ntohl(x)
-#else
-#define htonl(x) ((unsigned long)___htonl(x))
-#define ntohl(x) ((unsigned long)___ntohl(x))
-#endif
#define htons(x) ___htons(x)
#define ntohs(x) ___ntohs(x)

#endif /* OPTIMIZE */

+#endif /* KERNEL */
+

#endif /* _LINUX_BYTEORDER_GENERIC_H */