On Fri, Jun 13, 2014 at 04:18:15PM +0900, Simon Horman wrote:
> This helper is similar to addr_to_str but
> tries to convert the port rather than the address
> of a struct sockaddr_storage.
>
> This is in preparation for supporting
> an external agent check.
I may be wrong, but I'm seeing an endianness issue here, am I wrong ?
The sockaddr_storage stores in network order, so you cannot simply take
the port and print it using "%u" without first applying ntohs().
> +/* Tries to convert a sockaddr_storage port to text form. Upon success, the
> + * address family is returned so that it's easy for the caller to adapt to
> the
> + * output format. Zero is returned if the address family is not supported. -1
> + * is returned upon error, with errno set. AF_INET, AF_INET6 and AF_UNIX are
> + * supported.
> + */
> +int port_to_str(struct sockaddr_storage *addr, char *str, int size)
> +{
> +
> + uint16_t port;
> +
> +
> + if (size < 5)
> + return 0;
> + *str = '\0';
> +
> + switch (addr->ss_family) {
> + case AF_INET:
> + port = ((struct sockaddr_in *)addr)->sin_port;
> + break;
> + case AF_INET6:
> + port = ((struct sockaddr_in6 *)addr)->sin6_port;
> + break;
> + case AF_UNIX:
> + memcpy(str, "unix", 5);
> + return addr->ss_family;
> + default:
> + return 0;
> + }
> +
> + snprintf(str, size, "%u", port);
> + return addr->ss_family;
> +}
Willy
