printk: add %p6 format specifier for IPv6 addresses
Takes a pointer to a IPv6 address and formats it in the usual
colon-separated hex format:
xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx
Each 16 bit word is printed in network-endian byteorder.
%#p6 is also supported and will omit the colons.
%p6 is a replacement for NIP6_FMT and NIP6()
%#p6 is a replacement for NIP6_SEQFMT and NIP6()
Note that NIP6() took a struct in6_addr whereas this takes a pointer
to a struct in6_addr.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 0deaaaf..cb5bc04 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -598,6 +598,24 @@
return string(buf, end, mac_addr, field_width, precision, flags & ~SPECIAL);
}
+static char *ip6_addr_string(char *buf, char *end, u8 *addr, int field_width,
+ int precision, int flags)
+{
+ char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */
+ char *p = ip6_addr;
+ int i;
+
+ for (i = 0; i < 8; i++) {
+ p = pack_hex_byte(p, addr[2 * i]);
+ p = pack_hex_byte(p, addr[2 * i + 1]);
+ if (!(flags & SPECIAL) && i != 7)
+ *p++ = ':';
+ }
+ *p = '\0';
+
+ return string(buf, end, ip6_addr, field_width, precision, flags & ~SPECIAL);
+}
+
/*
* Show a '%p' thing. A kernel extension is that the '%p' is followed
* by an extra set of alphanumeric characters that are extended format
@@ -611,6 +629,8 @@
* addresses (not the name nor the flags)
* - 'M' For a 6-byte MAC address, it prints the address in the
* usual colon-separated hex notation
+ * - '6' For a IPv6 address prints the address in network-ordered 16 bit hex
+ * with colon separators
*
* Note: The difference between 'S' and 'F' is that on ia64 and ppc64
* function pointers are really function descriptors, which contain a
@@ -628,6 +648,8 @@
return resource_string(buf, end, ptr, field_width, precision, flags);
case 'M':
return mac_address_string(buf, end, ptr, field_width, precision, flags);
+ case '6':
+ return ip6_addr_string(buf, end, ptr, field_width, precision, flags);
}
flags |= SMALL;
if (field_width == -1) {
