[PATCH 5/8] util: Improve sockaddr initialisation in sock_l4()

[David Gibson <david@gibson.dropbear.id.au>]

Currently we initialise the address field of the sockaddrs we construct
to the any/unspecified address, but not in a very clear way: we use
explicit 0 values, which is only interpretable if you know the order of
fields in the sockaddr structures.  Use explicit field names, and explicit
initialiser macros for the address.

Because we initialise to this default value, we don't need to explicitly
set the any/unspecified address later on if the caller didn't pass an
overriding bind address.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 util.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/util.c b/util.c
index d465e48..0152ae6 100644
--- a/util.c
+++ b/util.c
@@ -105,12 +105,12 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 	struct sockaddr_in addr4 = {
 		.sin_family = AF_INET,
 		.sin_port = htons(port),
-		{ 0 }, { 0 },
+		.sin_addr = IN4ADDR_ANY_INIT,
 	};
 	struct sockaddr_in6 addr6 = {
 		.sin6_family = AF_INET6,
 		.sin6_port = htons(port),
-		0, IN6ADDR_ANY_INIT, 0,
+		.sin6_addr = IN6ADDR_ANY_INIT,
 	};
 	const struct sockaddr *sa;
 	bool dual_stack = false;
@@ -162,8 +162,6 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 	if (af == AF_INET) {
 		if (bind_addr)
 			addr4.sin_addr.s_addr = *(in_addr_t *)bind_addr;
-		else
-			addr4.sin_addr.s_addr = htonl(INADDR_ANY);
 
 		sa = (const struct sockaddr *)&addr4;
 		sl = sizeof(addr4);
@@ -174,8 +172,6 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 			if (!memcmp(bind_addr, &c->ip6.addr_ll,
 			    sizeof(c->ip6.addr_ll)))
 				addr6.sin6_scope_id = c->ifi6;
-		} else {
-			addr6.sin6_addr = in6addr_any;
 		}
 
 		sa = (const struct sockaddr *)&addr6;
-- 
@@ -105,12 +105,12 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 	struct sockaddr_in addr4 = {
 		.sin_family = AF_INET,
 		.sin_port = htons(port),
-		{ 0 }, { 0 },
+		.sin_addr = IN4ADDR_ANY_INIT,
 	};
 	struct sockaddr_in6 addr6 = {
 		.sin6_family = AF_INET6,
 		.sin6_port = htons(port),
-		0, IN6ADDR_ANY_INIT, 0,
+		.sin6_addr = IN6ADDR_ANY_INIT,
 	};
 	const struct sockaddr *sa;
 	bool dual_stack = false;
@@ -162,8 +162,6 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 	if (af == AF_INET) {
 		if (bind_addr)
 			addr4.sin_addr.s_addr = *(in_addr_t *)bind_addr;
-		else
-			addr4.sin_addr.s_addr = htonl(INADDR_ANY);
 
 		sa = (const struct sockaddr *)&addr4;
 		sl = sizeof(addr4);
@@ -174,8 +172,6 @@ int sock_l4(const struct ctx *c, int af, uint8_t proto,
 			if (!memcmp(bind_addr, &c->ip6.addr_ll,
 			    sizeof(c->ip6.addr_ll)))
 				addr6.sin6_scope_id = c->ifi6;
-		} else {
-			addr6.sin6_addr = in6addr_any;
 		}
 
 		sa = (const struct sockaddr *)&addr6;
-- 
2.43.0