Re: [PATCHv3] vsprintf: Add %pMR for Bluetooth MAC address

From: Andrei Emeltchenko
Date: Tue Jun 05 2012 - 07:57:21 EST


ping

On Mon, May 28, 2012 at 4:05 PM, Andrei Emeltchenko
<Andrei.Emeltchenko.news@xxxxxxxxx> wrote:
> From: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>
>
> Bluetooth uses mostly LE byte order which is reversed for visual
> interpretation. Currently in Bluetooth in use unsafe batostr function.
>
> This is slightly modified version of Joe Perches <joe@xxxxxxxxxxx>
> patch (sent Sat, Dec 4, 2010).
>
> Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@xxxxxxxxx>
> ---
>        v3: removed extra variable index
>        v2: changed bluetooth to reversed, syntax fixes
>
>  lib/vsprintf.c |   23 +++++++++++++++++++----
>  1 file changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/lib/vsprintf.c b/lib/vsprintf.c
> index abbabec..55052fa 100644
> --- a/lib/vsprintf.c
> +++ b/lib/vsprintf.c
> @@ -559,15 +559,28 @@ char *mac_address_string(char *buf, char *end, u8 *addr,
>        char *p = mac_addr;
>        int i;
>        char separator;
> +       bool reversed = false;
>
> -       if (fmt[1] == 'F') {            /* FDDI canonical format */
> +       switch (fmt[1]) {
> +       case 'F':
>                separator = '-';
> -       } else {
> +               break;
> +
> +       case 'R':
> +               reversed = true;
> +               /* fall through */
> +
> +       default:
>                separator = ':';
> +               break;
>        }
>
>        for (i = 0; i < 6; i++) {
> -               p = hex_byte_pack(p, addr[i]);
> +               if (reversed)
> +                       p = hex_byte_pack(p, addr[5 - i]);
> +               else
> +                       p = hex_byte_pack(p, addr[i]);
> +
>                if (fmt[0] == 'M' && i != 5)
>                        *p++ = separator;
>        }
> @@ -830,6 +843,7 @@ int kptr_restrict __read_mostly;
>  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
>  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
>  *       with a dash-separated hex notation
> + * - '[mM]R For a 6-byte MAC address, Reverse order (Bluetooth)
>  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
>  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
>  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
> @@ -890,7 +904,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
>                return resource_string(buf, end, ptr, spec, fmt);
>        case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
>        case 'm':                       /* Contiguous: 000102030405 */
> -                                       /* [mM]F (FDDI, bit reversed) */
> +                                       /* [mM]F (FDDI) */
> +                                       /* [mM]R (Reverse order; Bluetooth) */
>                return mac_address_string(buf, end, ptr, spec, fmt);
>        case 'I':                       /* Formatted IP supported
>                                         * 4:   1.2.3.4
> --
> 1.7.9.5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/