From fcbb6fed85ea9ff4feb4f1ebd4f0f235fdaf06b6 Mon Sep 17 00:00:00 2001
From: David Heidelberger <david.heidelberger@ixit.cz>
Date: Mon, 29 Jun 2015 16:53:03 +0200
Subject: [PATCH 3/3] uapi/if_ether.h: prevent redefinition of struct ethhdr
Musl provides its own ethhdr struct definition. Add a guard to prevent
its definition of the appropriate musl header has already been included.
Signed-off-by: John Spencer <maillist-linux@barfooze.de>
Tested-by: David Heidelberger <david.heidelberger@ixit.cz>
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
---
include/uapi/linux/if_ether.h | 3 +++
include/uapi/linux/libc-compat.h | 11 +++++++++++
2 files changed, 14 insertions(+)
--- a/include/uapi/linux/if_ether.h
+++ b/include/uapi/linux/if_ether.h
@@ -22,6 +22,7 @@
#define _UAPI_LINUX_IF_ETHER_H
#include <linux/types.h>
+#include <linux/libc-compat.h>
/*
* IEEE 802.3 Ethernet magic constants. The frame sizes omit the preamble
@@ -135,11 +136,13 @@
* This is an Ethernet frame header.
*/
+#if __UAPI_DEF_ETHHDR
struct ethhdr {
unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
unsigned char h_source[ETH_ALEN]; /* source ether addr */
__be16 h_proto; /* packet type ID field */
} __attribute__((packed));
+#endif
#endif /* _UAPI_LINUX_IF_ETHER_H */
--- a/include/uapi/linux/libc-compat.h
+++ b/include/uapi/linux/libc-compat.h
@@ -85,6 +85,14 @@
#endif /* _NET_IF_H */
+/* musl defines the ethhdr struct itself in its netinet/if_ether.h.
+ * Glibc just includes the kernel header and uses a different guard. */
+#if defined(_NETINET_IF_ETHER_H)
+#define __UAPI_DEF_ETHHDR 0
+#else
+#define __UAPI_DEF_ETHHDR 1
+#endif
+
/* Coordinate with libc netinet/in.h header. */
#if defined(_NETINET_IN_H)
@@ -161,6 +169,9 @@
/* For the future if glibc adds IFF_LOWER_UP, IFF_DORMANT and IFF_ECHO */
#define __UAPI_DEF_IF_NET_DEVICE_FLAGS_LOWER_UP_DORMANT_ECHO 1
+/* Definitions for if_ether.h */
+#define __UAPI_DEF_ETHHDR 1
+
/* Definitions for in.h */
#define __UAPI_DEF_IN_ADDR 1
#define __UAPI_DEF_IN_IPPROTO 1