[LEDE-DEV] [PATCH] umdns: Replace unnecessary memset calls with {}.

[John Crispin]

On 07/11/17 21:24, Rosen Penev wrote:
> Less verbose
>
> Signed-off-by: Rosen Penev <rosenp at gmail.com>
> ---

Hi,

this does not fix any bugs and is a pure style change. yeah, it might 
safe a few bytes but i dont see that as a valid trade-off, sorry ...

     John

>   interface.c | 22 ++++++++--------------
>   1 file changed, 8 insertions(+), 14 deletions(-)
>
> diff --git a/interface.c b/interface.c
> index 7f814d2..18dee52 100644
> --- a/interface.c
> +++ b/interface.c
> @@ -44,7 +44,7 @@
>   static int
>   interface_send_packet4(struct interface *iface, struct sockaddr_in *to, struct iovec *iov, int iov_len)
>   {
> -	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1];
> +	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in_pktinfo)) / sizeof(size_t)) + 1] = {};
>   	static struct sockaddr_in a;
>   	static struct msghdr m = {
>   		.msg_name = (struct sockaddr *) &a,
> @@ -61,7 +61,6 @@ interface_send_packet4(struct interface *iface, struct sockaddr_in *to, struct i
>   	m.msg_iov = iov;
>   	m.msg_iovlen = iov_len;
>   
> -	memset(cmsg_data, 0, sizeof(cmsg_data));
>   	cmsg = CMSG_FIRSTHDR(&m);
>   	cmsg->cmsg_len = m.msg_controllen;
>   	cmsg->cmsg_level = IPPROTO_IP;
> @@ -84,7 +83,7 @@ interface_send_packet4(struct interface *iface, struct sockaddr_in *to, struct i
>   static int
>   interface_send_packet6(struct interface *iface, struct sockaddr_in6 *to, struct iovec *iov, int iov_len)
>   {
> -	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in6_pktinfo)) / sizeof(size_t)) + 1];
> +	static size_t cmsg_data[( CMSG_SPACE(sizeof(struct in6_pktinfo)) / sizeof(size_t)) + 1] = {};
>   	static struct sockaddr_in6 a;
>   	static struct msghdr m = {
>   		.msg_name = (struct sockaddr *) &a,
> @@ -101,7 +100,6 @@ interface_send_packet6(struct interface *iface, struct sockaddr_in6 *to, struct
>   	m.msg_iov = iov;
>   	m.msg_iovlen = iov_len;
>   
> -	memset(cmsg_data, 0, sizeof(cmsg_data));
>   	cmsg = CMSG_FIRSTHDR(&m);
>   	cmsg->cmsg_len = m.msg_controllen;
>   	cmsg->cmsg_level = IPPROTO_IPV6;
> @@ -186,7 +184,7 @@ read_socket4(struct uloop_fd *u, unsigned int events)
>   	struct iovec iov[1];
>   	char cmsg[CMSG_SPACE(sizeof(struct in_pktinfo)) + CMSG_SPACE(sizeof(int)) + 1];
>   	struct cmsghdr *cmsgptr;
> -	struct msghdr msg;
> +	struct msghdr msg = {};
>   	socklen_t len;
>   	struct sockaddr_in from;
>   	int flags = 0, ifindex = -1;
> @@ -202,7 +200,6 @@ read_socket4(struct uloop_fd *u, unsigned int events)
>   	iov[0].iov_base = buffer;
>   	iov[0].iov_len = sizeof(buffer);
>   
> -	memset(&msg, 0, sizeof(msg));
>   	msg.msg_name = (struct sockaddr *) &from;
>   	msg.msg_namelen = sizeof(struct sockaddr_in);
>   	msg.msg_iov = iov;
> @@ -260,7 +257,7 @@ read_socket6(struct uloop_fd *u, unsigned int events)
>   	struct iovec iov[1];
>   	char cmsg6[CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(sizeof(int)) + 1];
>   	struct cmsghdr *cmsgptr;
> -	struct msghdr msg;
> +	struct msghdr msg = {};
>   	socklen_t len;
>   	struct sockaddr_in6 from;
>   	int flags = 0, ifindex = -1;
> @@ -276,7 +273,6 @@ read_socket6(struct uloop_fd *u, unsigned int events)
>   	iov[0].iov_base = buffer;
>   	iov[0].iov_len = sizeof(buffer);
>   
> -	memset(&msg, 0, sizeof(msg));
>   	msg.msg_name = (struct sockaddr *) &from;
>   	msg.msg_namelen = sizeof(struct sockaddr_in6);
>   	msg.msg_iov = iov;
> @@ -327,17 +323,16 @@ read_socket6(struct uloop_fd *u, unsigned int events)
>   static int
>   interface_mcast_setup4(struct interface *iface)
>   {
> -	struct ip_mreqn mreq;
> +	struct ip_mreqn mreq = {};
>   	uint8_t ttl = 255;
>   	int no = 0;
> -	struct sockaddr_in sa = { 0 };
> +	struct sockaddr_in sa = {};
>   	int fd = iface->fd.fd;
>   
>   	sa.sin_family = AF_INET;
>   	sa.sin_port = htons(MCAST_PORT);
>   	inet_pton(AF_INET, MCAST_ADDR, &sa.sin_addr);
>   
> -	memset(&mreq, 0, sizeof(mreq));
>   	mreq.imr_address.s_addr = iface->v4_addr.s_addr;
>   	mreq.imr_multiaddr = sa.sin_addr;
>   	mreq.imr_ifindex = iface->ifindex;
> @@ -368,17 +363,16 @@ interface_mcast_setup4(struct interface *iface)
>   static int
>   interface_socket_setup6(struct interface *iface)
>   {
> -	struct ipv6_mreq mreq;
> +	struct ipv6_mreq mreq = {};
>   	int ttl = 255;
>   	int no = 0;
> -	struct sockaddr_in6 sa = { 0 };
> +	struct sockaddr_in6 sa = {};
>   	int fd = iface->fd.fd;
>   
>   	sa.sin6_family = AF_INET6;
>   	sa.sin6_port = htons(MCAST_PORT);
>   	inet_pton(AF_INET6, MCAST_ADDR6, &sa.sin6_addr);
>   
> -	memset(&mreq, 0, sizeof(mreq));
>   	mreq.ipv6mr_multiaddr = sa.sin6_addr;
>   	mreq.ipv6mr_interface = iface->ifindex;
>