api: fix compatibility of linux/in.h with netinet/in.h

u
This fixes breakage to iproute2 build with recent kernel headers
caused by:
   commit a263653ed798216c0069922d7b5237ca49436007
   Author: Pablo Neira Ayuso <pablo@netfilter.org>
   Date:   Wed Jun 17 10:28:27 2015 -0500

   netfilter: don't pull include/linux/netfilter.h from netns headers

The issue is that definitions in linux/in.h overlap with those
in netinet/in.h. This patch solves this by introducing the same
mechanism as was used to solve the same problem with linux/in6.h

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 35 insertions, 3 deletions

diff --git a/include/uapi/linux/in.h b/include/uapi/linux/in.h
index 83d6236a2f08..eaf94919291a 100644
--- a/include/uapi/linux/in.h
+++ b/include/uapi/linux/in.h
@@ -19,8 +19,10 @@
 #define _UAPI_LINUX_IN_H
 
 #include <linux/types.h>
+#include <linux/libc-compat.h>
 #include <linux/socket.h>
 
+#if __UAPI_DEF_IN_IPPROTO
 /* Standard well-defined IP protocols.  */
 enum {
   IPPROTO_IP = 0,               /* Dummy protocol for TCP               */
@@ -75,12 +77,14 @@ enum {
 #define IPPROTO_RAW             IPPROTO_RAW
   IPPROTO_MAX
 };
+#endif
 
-
+#if __UAPI_DEF_IN_ADDR
 /* Internet address. */
 struct in_addr {
         __be32  s_addr;
 };
+#endif
 
 #define IP_TOS          1
 #define IP_TTL          2
@@ -158,6 +162,7 @@ struct in_addr {
 
 /* Request struct for multicast socket ops */
 
+#if __UAPI_DEF_IP_MREQ
 struct ip_mreq  {
         struct in_addr imr_multiaddr;   /* IP multicast address of group */
         struct in_addr imr_interface;   /* local IP address of interface */
@@ -209,14 +214,18 @@ struct group_filter {
 #define GROUP_FILTER_SIZE(numsrc) \
         (sizeof(struct group_filter) - sizeof(struct __kernel_sockaddr_storage) \
         + (numsrc) * sizeof(struct __kernel_sockaddr_storage))
+#endif
 
+#if __UAPI_DEF_IN_PKTINFO
 struct in_pktinfo {
         int             ipi_ifindex;
         struct in_addr  ipi_spec_dst;
         struct in_addr  ipi_addr;
 };
+#endif
 
 /* Structure describing an Internet (IP) socket address. */
+#if  __UAPI_DEF_SOCKADDR_IN
 #define __SOCK_SIZE__   16              /* sizeof(struct sockaddr)      */
 struct sockaddr_in {
   __kernel_sa_family_t  sin_family;     /* Address family               */
@@ -228,8 +237,9 @@ struct sockaddr_in {
                         sizeof(unsigned short int) - sizeof(struct in_addr)];
 };
 #define sin_zero        __pad           /* for BSD UNIX comp. -FvK      */
+#endif
 
-
+#if __UAPI_DEF_IN_CLASS
 /*
  * Definitions of the bits in an Internet address integer.
  * On subnets, host and network parts are found according
@@ -280,7 +290,7 @@ struct sockaddr_in {
 #define INADDR_ALLHOSTS_GROUP   0xe0000001U     /* 224.0.0.1   */
 #define INADDR_ALLRTRS_GROUP    0xe0000002U     /* 224.0.0.2 */
 #define INADDR_MAX_LOCAL_GROUP  0xe00000ffU     /* 224.0.0.255 */
-
+#endif
 
 /* <asm/byteorder.h> contains the htonl type stuff.. */
 #include <asm/byteorder.h> 
diff --git a/include/uapi/linux/libc-compat.h b/include/uapi/linux/libc-compat.h
index fa673e9cc040..7d024ceb075d 100644
--- a/include/uapi/linux/libc-compat.h
+++ b/include/uapi/linux/libc-compat.h
@@ -56,6 +56,13 @@
 
 /* GLIBC headers included first so don't define anything
  * that would already be defined. */
+#define __UAPI_DEF_IN_ADDR              0
+#define __UAPI_DEF_IN_IPPROTO           0
+#define __UAPI_DEF_IN_PKTINFO           0
+#define __UAPI_DEF_IP_MREQ              0
+#define __UAPI_DEF_SOCKADDR_IN          0
+#define __UAPI_DEF_IN_CLASS             0
+
 #define __UAPI_DEF_IN6_ADDR             0
 /* The exception is the in6_addr macros which must be defined
  * if the glibc code didn't define them. This guard matches
@@ -78,6 +85,13 @@
 /* Linux headers included first, and we must define everything
  * we need. The expectation is that glibc will check the
  * __UAPI_DEF_* defines and adjust appropriately. */
+#define __UAPI_DEF_IN_ADDR              1
+#define __UAPI_DEF_IN_IPPROTO           1
+#define __UAPI_DEF_IN_PKTINFO           1
+#define __UAPI_DEF_IP_MREQ              1
+#define __UAPI_DEF_SOCKADDR_IN          1
+#define __UAPI_DEF_IN_CLASS             1
+
 #define __UAPI_DEF_IN6_ADDR             1
 /* We unconditionally define the in6_addr macros and glibc must
  * coordinate. */
@@ -103,6 +117,14 @@
  * that we need. */
 #else /* !defined(__GLIBC__) */
 
+/* Definitions for in.h */
+#define __UAPI_DEF_IN_ADDR              1
+#define __UAPI_DEF_IN_IPPROTO           1
+#define __UAPI_DEF_IN_PKTINFO           1
+#define __UAPI_DEF_IP_MREQ              1
+#define __UAPI_DEF_SOCKADDR_IN          1
+#define __UAPI_DEF_IN_CLASS             1
+
 /* Definitions for in6.h */
 #define __UAPI_DEF_IN6_ADDR             1
 #define __UAPI_DEF_IN6_ADDR_ALT         1