Commit 8a27f7c9 authored by Joe Perches's avatar Joe Perches Committed by David S. Miller
Browse files

lib/vsprintf.c: Add "%pI6c" - print pointer as compressed ipv6 address 



Signed-off-by: default avatarJoe Perches <joe@perches.com>
Tested-by: default avatarJens Rosenboom <jens@mcbone.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9a7030b7

lib/vsprintf.c

+152 −47
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@ 
#include <linux/kallsyms.h>

#include <linux/uaccess.h>

#include <linux/ioport.h>

#include <net/addrconf.h>



#include <asm/page.h>		/* for PAGE_SIZE */

#include <asm/div64.h>
@@ -630,60 +631,156 @@ static char *resource_string(char *buf, char *end, struct resource *res, 
}



static char *mac_address_string(char *buf, char *end, u8 *addr,

				struct printf_spec spec)

				struct printf_spec spec, const char *fmt)

{

	char mac_addr[6 * 3]; /* (6 * 2 hex digits), 5 colons and trailing zero */

	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];

	char *p = mac_addr;

	int i;



	for (i = 0; i < 6; i++) {

		p = pack_hex_byte(p, addr[i]);

		if (!(spec.flags & SPECIAL) && i != 5)

		if (fmt[0] == 'M' && i != 5)

			*p++ = ':';

	}

	*p = '\0';

	spec.flags &= ~SPECIAL;



	return string(buf, end, mac_addr, spec);

}



static char *ip6_addr_string(char *buf, char *end, u8 *addr,

				struct printf_spec spec)

static char *ip4_string(char *p, const u8 *addr, bool leading_zeros)

{

	int i;



	for (i = 0; i < 4; i++) {

		char temp[3];	/* hold each IP quad in reverse order */

		int digits = put_dec_trunc(temp, addr[i]) - temp;

		if (leading_zeros) {

			if (digits < 3)

				*p++ = '0';

			if (digits < 2)

				*p++ = '0';

		}

		/* reverse the digits in the quad */

		while (digits--)

			*p++ = temp[digits];

		if (i < 3)

			*p++ = '.';

	}



	*p = '\0';

	return p;

}



static char *ip6_compressed_string(char *p, const struct in6_addr *addr)

{

	char ip6_addr[8 * 5]; /* (8 * 4 hex digits), 7 colons and trailing zero */

	char *p = ip6_addr;

	int i;

	int j;

	int range;

	unsigned char zerolength[8];

	int longest = 1;

	int colonpos = -1;

	u16 word;

	u8 hi;

	u8 lo;

	bool needcolon = false;

	bool useIPv4 = ipv6_addr_v4mapped(addr) || ipv6_addr_is_isatap(addr);



	memset(zerolength, 0, sizeof(zerolength));



	if (useIPv4)

		range = 6;

	else

		range = 8;



	/* find position of longest 0 run */

	for (i = 0; i < range; i++) {

		for (j = i; j < range; j++) {

			if (addr->s6_addr16[j] != 0)

				break;

			zerolength[i]++;

		}

	}

	for (i = 0; i < range; i++) {

		if (zerolength[i] > longest) {

			longest = zerolength[i];

			colonpos = i;

		}

	}



	/* emit address */

	for (i = 0; i < range; i++) {

		if (i == colonpos) {

			if (needcolon || i == 0)

				*p++ = ':';

			*p++ = ':';

			needcolon = false;

			i += longest - 1;

			continue;

		}

		if (needcolon) {

			*p++ = ':';

			needcolon = false;

		}

		/* hex u16 without leading 0s */

		word = ntohs(addr->s6_addr16[i]);

		hi = word >> 8;

		lo = word & 0xff;

		if (hi) {

			if (hi > 0x0f)

				p = pack_hex_byte(p, hi);

			else

				*p++ = hex_asc_lo(hi);

		}

		if (hi || lo > 0x0f)

			p = pack_hex_byte(p, lo);

		else

			*p++ = hex_asc_lo(lo);

		needcolon = true;

	}



	if (useIPv4) {

		if (needcolon)

			*p++ = ':';

		p = ip4_string(p, &addr->s6_addr[12], false);

	}



	*p = '\0';

	return p;

}



static char *ip6_string(char *p, const struct in6_addr *addr, const char *fmt)

{

	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 (!(spec.flags & SPECIAL) && i != 7)

		p = pack_hex_byte(p, addr->s6_addr[2 * i]);

		p = pack_hex_byte(p, addr->s6_addr[2 * i + 1]);

		if (fmt[0] == 'I' && i != 7)

			*p++ = ':';

	}



	*p = '\0';

	spec.flags &= ~SPECIAL;

	return p;

}



static char *ip6_addr_string(char *buf, char *end, const u8 *addr,

			     struct printf_spec spec, const char *fmt)

{

	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];



	if (fmt[0] == 'I' && fmt[2] == 'c')

		ip6_compressed_string(ip6_addr, (const struct in6_addr *)addr);

	else

		ip6_string(ip6_addr, (const struct in6_addr *)addr, fmt);



	return string(buf, end, ip6_addr, spec);

}



static char *ip4_addr_string(char *buf, char *end, u8 *addr,

				struct printf_spec spec)

static char *ip4_addr_string(char *buf, char *end, const u8 *addr,

			     struct printf_spec spec, const char *fmt)

{

	char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */

	char temp[3];	/* hold each IP quad in reverse order */

	char *p = ip4_addr;

	int i, digits;

	char ip4_addr[sizeof("255.255.255.255")];



	for (i = 0; i < 4; i++) {

		digits = put_dec_trunc(temp, addr[i]) - temp;

		/* reverse the digits in the quad */

		while (digits--)

			*p++ = temp[digits];

		if (i != 3)

			*p++ = '.';

	}

	*p = '\0';

	spec.flags &= ~SPECIAL;

	ip4_string(ip4_addr, addr, fmt[0] == 'i');



	return string(buf, end, ip4_addr, spec);

}
@@ -702,11 +799,15 @@ static char *ip4_addr_string(char *buf, char *end, u8 *addr, 
 *       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

 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated

 *       decimal for v4 and colon separated network-order 16 bit hex for v6)

 * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is

 *       currently the same

 *

 * - 'm' For a 6-byte MAC address, it prints the hex address without colons

 * - '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

 * - 'i' [46] for 'raw' IPv4/IPv6 addresses

 *       IPv6 omits the colons (01020304...0f)

 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)

 * - 'I6c' for IPv6 addresses printed as specified by

 *       http://www.ietf.org/id/draft-kawamura-ipv6-text-representation-03.txt

 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64

 * function pointers are really function descriptors, which contain a

 * pointer to the real address.
@@ -726,20 +827,24 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr, 
		return symbol_string(buf, end, ptr, spec, *fmt);

	case 'R':

		return resource_string(buf, end, ptr, spec);

	case 'm':

		spec.flags |= SPECIAL;

		/* Fallthrough */

	case 'M':

		return mac_address_string(buf, end, ptr, spec);

	case 'i':

		spec.flags |= SPECIAL;

		/* Fallthrough */

	case 'I':

		if (fmt[1] == '6')

			return ip6_addr_string(buf, end, ptr, spec);

		if (fmt[1] == '4')

			return ip4_addr_string(buf, end, ptr, spec);

		spec.flags &= ~SPECIAL;

	case 'M':			/* Colon separated: 00:01:02:03:04:05 */

	case 'm':			/* Contiguous: 000102030405 */

		return mac_address_string(buf, end, ptr, spec, fmt);

	case 'I':			/* Formatted IP supported

					 * 4:	1.2.3.4

					 * 6:	0001:0203:...:0708

					 * 6c:	1::708 or 1::1.2.3.4

					 */

	case 'i':			/* Contiguous:

					 * 4:	001.002.003.004

					 * 6:   000102...0f

					 */

		switch (fmt[1]) {

		case '6':

			return ip6_addr_string(buf, end, ptr, spec, fmt);

		case '4':

			return ip4_addr_string(buf, end, ptr, spec, fmt);

		}

		break;

	}

	spec.flags |= SMALL;