dhcpcd-discuss

Hi Roman

On 01/08/2019 08:34, urv wrote:
> Hello, Roy!
>
> Build dhcpcd v.8.0 and newer on quite old kernel 3.10 finish with error:
>
> if-linux.c: In function ‘if_address’:
> if-linux.c:1511:38: error: ‘IFA_FLAGS’ undeclared (first use in this 
> function)
>     add_attr_32(&nlm.hdr, sizeof(nlm), IFA_FLAGS, flags);
>                                        ^~~~~~~~~
> if-linux.c:1511:38: note: each undeclared identifier is reported only 
> once for each function it appears in
> if-linux.c: In function ‘if_address6’:
> if-linux.c:1585:38: error: ‘IFA_FLAGS’ undeclared (first use in this 
> function)
>     add_attr_32(&nlm.hdr, sizeof(nlm), IFA_FLAGS, flags);
>                                        ^~~~~~~~~
>
> Problem appear with commit "d1468fbdad0e288b23c9e5181d1de4476691ae61"
> And yes, header file "linux/if_addr.h" doesn't have declaration of 
> 'IFA_FLAGS'

What I want for Christmas is for linux headers to use #defines.
Sadly this patch will have to do. Does it fix your compile issue?

Roy

diff --git a/src/if-linux.c b/src/if-linux.c
index 3919bff5..b7e84eb5 100644
--- a/src/if-linux.c
+++ b/src/if-linux.c
@@ -1480,7 +1480,9 @@ if_address(unsigned char cmd, const struct ipv4_addr *ia)
 	struct nlma nlm;
 	struct ifa_cacheinfo cinfo;
 	int retval = 0;
+#ifdef IFA_F_NOPREFIXROUTE
 	uint32_t flags = 0;
+#endif
 
 	memset(&nlm, 0, sizeof(nlm));
 	nlm.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
@@ -1507,8 +1509,8 @@ if_address(unsigned char cmd, const struct ipv4_addr *ia)
 #ifdef IFA_F_NOPREFIXROUTE
 		if (nlm.ifa.ifa_prefixlen < 32)
 			flags |= IFA_F_NOPREFIXROUTE;
-#endif
 		add_attr_32(&nlm.hdr, sizeof(nlm), IFA_FLAGS, flags);
+#endif
 
 		add_attr_l(&nlm.hdr, sizeof(nlm), IFA_BROADCAST,
 		    &ia->brd.s_addr, sizeof(ia->brd.s_addr));
@@ -1542,7 +1544,9 @@ if_address6(unsigned char cmd, const struct ipv6_addr *ia)
 {
 	struct nlma nlm;
 	struct ifa_cacheinfo cinfo;
+#if defined(IFA_F_MANAGETEMPADDR) || defined(IFA_F_NOPREFIXROUTE)
 	uint32_t flags = 0;
+#endif
 
 	memset(&nlm, 0, sizeof(nlm));
 	nlm.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
@@ -1582,7 +1586,9 @@ if_address6(unsigned char cmd, const struct ipv6_addr *ia)
 		if (!IN6_IS_ADDR_LINKLOCAL(&ia->addr))
 			flags |= IFA_F_NOPREFIXROUTE;
 #endif
+#if defined(IFA_F_MANAGETEMPADDR) || defined(IFA_F_NOPREFIXROUTE)
 		add_attr_32(&nlm.hdr, sizeof(nlm), IFA_FLAGS, flags);
+#endif
 
 		memset(&cinfo, 0, sizeof(cinfo));
 		cinfo.ifa_prefered = ia->prefix_pltime;