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| author | Andrei Emeltchenko <andrei.emeltchenko@intel.com> | 2012-07-30 14:40:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-30 17:25:14 -0700 |
| commit | 76597ff989a1fbaa9b9a1e54007cd759bf257ab7 (patch) | |
| tree | 51c5a7e99de7ff2ba88ba73b110a60c623c5d32c | |
| parent | 61e99ab8e35a88b8c4d0f80d3df9ee16df471be5 (diff) | |
| download | lwn-76597ff989a1fbaa9b9a1e54007cd759bf257ab7.tar.gz lwn-76597ff989a1fbaa9b9a1e54007cd759bf257ab7.zip | |
vsprintf: add %pMR for Bluetooth MAC address
Bluetooth uses mostly LE byte order which is reversed for visual
interpretation. Currently in Bluetooth in use unsafe batostr function.
This is a slightly modified version of Joe's patch (sent Sat, Dec 4,
2010).
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Cc: Joe Perches <joe@perches.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | Documentation/printk-formats.txt | 5 | ||||
| -rw-r--r-- | lib/vsprintf.c | 23 |
2 files changed, 24 insertions, 4 deletions
diff --git a/Documentation/printk-formats.txt b/Documentation/printk-formats.txt index 5df176ed59b8..d8d168fa79d6 100644 --- a/Documentation/printk-formats.txt +++ b/Documentation/printk-formats.txt @@ -56,6 +56,7 @@ Struct Resources: MAC/FDDI addresses: %pM 00:01:02:03:04:05 + %pMR 05:04:03:02:01:00 %pMF 00-01-02-03-04-05 %pm 000102030405 @@ -67,6 +68,10 @@ MAC/FDDI addresses: the 'M' specifier to use dash ('-') separators instead of the default separator. + For Bluetooth addresses the 'R' specifier shall be used after the 'M' + specifier to use reversed byte order suitable for visual interpretation + of Bluetooth addresses which are in the little endian order. + IPv4 addresses: %pI4 1.2.3.4 diff --git a/lib/vsprintf.c b/lib/vsprintf.c index c3f36d415bdf..736974576e2d 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -662,15 +662,28 @@ 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; } @@ -933,6 +946,7 @@ 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 @@ -995,7 +1009,8 @@ 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 |