net: Make linux/tcp.h C++ friendly (trivial)

I originally sent this patch to <trivial@kernel.org>, but Jiri Kosina did
not feel that this is fully appropriate for the trivial tree.

Using linux/tcp.h from C++ results in:

cat t.cc
#include <linux/tcp.h>
int main() { }

g++ -c t.cc

In file included from t.cc:1:
/usr/include/linux/tcp.h:72: error: '__u32 __fswab32(__u32)' cannot appear in a constant-expression
/usr/include/linux/tcp.h:72: error: a function call cannot appear in a constant-expression
...

Attached trivial patch fixes this problem.

Tested:
- the t.cc above compiles with g++ and
- the following program generates the same output before/after
  the patch:

#include <linux/tcp.h>
#include <stdio.h>

int main ()
{
#define P(a) printf("%s: %08x\n", #a, (int)a)
 P(TCP_FLAG_CWR);
 P(TCP_FLAG_ECE);
 P(TCP_FLAG_URG);
 P(TCP_FLAG_ACK);
 P(TCP_FLAG_PSH);
 P(TCP_FLAG_RST);
 P(TCP_FLAG_SYN);
 P(TCP_FLAG_FIN);
 P(TCP_RESERVED_BITS);
 P(TCP_DATA_OFFSET);
#undef P
 return 0;
}

Signed-off-by: Paul Pluzhnikov <ppluzhnikov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Paul Pluzhnikov 2012-06-09 07:53:03 -07:00 committed by David S. Miller
parent f41ef2e7dc
commit 8876d6b5f8

View File

@ -69,16 +69,16 @@ union tcp_word_hdr {
#define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3])
enum {
TCP_FLAG_CWR = __cpu_to_be32(0x00800000),
TCP_FLAG_ECE = __cpu_to_be32(0x00400000),
TCP_FLAG_URG = __cpu_to_be32(0x00200000),
TCP_FLAG_ACK = __cpu_to_be32(0x00100000),
TCP_FLAG_PSH = __cpu_to_be32(0x00080000),
TCP_FLAG_RST = __cpu_to_be32(0x00040000),
TCP_FLAG_SYN = __cpu_to_be32(0x00020000),
TCP_FLAG_FIN = __cpu_to_be32(0x00010000),
TCP_RESERVED_BITS = __cpu_to_be32(0x0F000000),
TCP_DATA_OFFSET = __cpu_to_be32(0xF0000000)
TCP_FLAG_CWR = __constant_cpu_to_be32(0x00800000),
TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000),
TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000),
TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000),
TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000),
TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000),
TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000),
TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000),
TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000),
TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000)
};
/*