kernel_optimize_test/lib/vsprintf.c
André Goddard Rosa 922ac25c9f vsprintf: reuse almost identical simple_strtoulX() functions
The difference between simple_strtoul() and simple_strtoull() is just
the size of the variable used to keep track of the sum of characters
converted to numbers:

unsigned long simple_strtoul() {...}
unsigned long long simple_strtoull(){...}

Both are same size on my Core 2/gcc 4.4.1.
Overflow condition is not checked on both functions, so an extremely large
string can break these functions so that they don't even notice it.

As we do not care for overflowing on these functions, always keep the sum
using the larger variable around (unsigned long long) on simple_strtoull()
and cast it to (unsigned long) on simple_strtoul(), which then becomes
just a wrapper around simple_strtoull().

Code size decreases by 304 bytes:
   text    data     bss     dec     hex filename
  15534       0       8   15542    3cb6 vsprintf.o (ex lib/lib.a-BEFORE)
  15230       0       8   15238    3b86 vsprintf.o (ex lib/lib.a-AFTER)

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15 08:53:32 -08:00

2016 lines
46 KiB
C

/*
* linux/lib/vsprintf.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
/*
* Wirzenius wrote this portably, Torvalds fucked it up :-)
*/
/*
* Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
* - changed to provide snprintf and vsnprintf functions
* So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
* - scnprintf and vscnprintf
*/
#include <stdarg.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/kernel.h>
#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>
#include <asm/sections.h> /* for dereference_function_descriptor() */
/* Works only for digits and letters, but small and fast */
#define TOLOWER(x) ((x) | 0x20)
static unsigned int simple_guess_base(const char *cp)
{
if (cp[0] == '0') {
if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
return 16;
else
return 8;
} else {
return 10;
}
}
/**
* simple_strtoull - convert a string to an unsigned long long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
{
unsigned long long result = 0;
if (!base)
base = simple_guess_base(cp);
if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
cp += 2;
while (isxdigit(*cp)) {
unsigned int value;
value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
if (value >= base)
break;
result = result * base + value;
cp++;
}
if (endp)
*endp = (char *)cp;
return result;
}
EXPORT_SYMBOL(simple_strtoull);
/**
* simple_strtoul - convert a string to an unsigned long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
{
return simple_strtoull(cp, endp, base);
}
EXPORT_SYMBOL(simple_strtoul);
/**
* simple_strtol - convert a string to a signed long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
long simple_strtol(const char *cp, char **endp, unsigned int base)
{
if (*cp == '-')
return -simple_strtoul(cp + 1, endp, base);
return simple_strtoul(cp, endp, base);
}
EXPORT_SYMBOL(simple_strtol);
/**
* simple_strtoll - convert a string to a signed long long
* @cp: The start of the string
* @endp: A pointer to the end of the parsed string will be placed here
* @base: The number base to use
*/
long long simple_strtoll(const char *cp, char **endp, unsigned int base)
{
if (*cp == '-')
return -simple_strtoull(cp + 1, endp, base);
return simple_strtoull(cp, endp, base);
}
/**
* strict_strtoul - convert a string to an unsigned long strictly
* @cp: The string to be converted
* @base: The number base to use
* @res: The converted result value
*
* strict_strtoul converts a string to an unsigned long only if the
* string is really an unsigned long string, any string containing
* any invalid char at the tail will be rejected and -EINVAL is returned,
* only a newline char at the tail is acceptible because people generally
* change a module parameter in the following way:
*
* echo 1024 > /sys/module/e1000/parameters/copybreak
*
* echo will append a newline to the tail.
*
* It returns 0 if conversion is successful and *res is set to the converted
* value, otherwise it returns -EINVAL and *res is set to 0.
*
* simple_strtoul just ignores the successive invalid characters and
* return the converted value of prefix part of the string.
*/
int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
{
char *tail;
unsigned long val;
size_t len;
*res = 0;
len = strlen(cp);
if (len == 0)
return -EINVAL;
val = simple_strtoul(cp, &tail, base);
if (tail == cp)
return -EINVAL;
if ((*tail == '\0') ||
((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
*res = val;
return 0;
}
return -EINVAL;
}
EXPORT_SYMBOL(strict_strtoul);
/**
* strict_strtol - convert a string to a long strictly
* @cp: The string to be converted
* @base: The number base to use
* @res: The converted result value
*
* strict_strtol is similiar to strict_strtoul, but it allows the first
* character of a string is '-'.
*
* It returns 0 if conversion is successful and *res is set to the converted
* value, otherwise it returns -EINVAL and *res is set to 0.
*/
int strict_strtol(const char *cp, unsigned int base, long *res)
{
int ret;
if (*cp == '-') {
ret = strict_strtoul(cp + 1, base, (unsigned long *)res);
if (!ret)
*res = -(*res);
} else {
ret = strict_strtoul(cp, base, (unsigned long *)res);
}
return ret;
}
EXPORT_SYMBOL(strict_strtol);
/**
* strict_strtoull - convert a string to an unsigned long long strictly
* @cp: The string to be converted
* @base: The number base to use
* @res: The converted result value
*
* strict_strtoull converts a string to an unsigned long long only if the
* string is really an unsigned long long string, any string containing
* any invalid char at the tail will be rejected and -EINVAL is returned,
* only a newline char at the tail is acceptible because people generally
* change a module parameter in the following way:
*
* echo 1024 > /sys/module/e1000/parameters/copybreak
*
* echo will append a newline to the tail of the string.
*
* It returns 0 if conversion is successful and *res is set to the converted
* value, otherwise it returns -EINVAL and *res is set to 0.
*
* simple_strtoull just ignores the successive invalid characters and
* return the converted value of prefix part of the string.
*/
int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res)
{
char *tail;
unsigned long long val;
size_t len;
*res = 0;
len = strlen(cp);
if (len == 0)
return -EINVAL;
val = simple_strtoull(cp, &tail, base);
if (tail == cp)
return -EINVAL;
if ((*tail == '\0') ||
((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
*res = val;
return 0;
}
return -EINVAL;
}
EXPORT_SYMBOL(strict_strtoull);
/**
* strict_strtoll - convert a string to a long long strictly
* @cp: The string to be converted
* @base: The number base to use
* @res: The converted result value
*
* strict_strtoll is similiar to strict_strtoull, but it allows the first
* character of a string is '-'.
*
* It returns 0 if conversion is successful and *res is set to the converted
* value, otherwise it returns -EINVAL and *res is set to 0.
*/
int strict_strtoll(const char *cp, unsigned int base, long long *res)
{
int ret;
if (*cp == '-') {
ret = strict_strtoull(cp + 1, base, (unsigned long long *)res);
if (!ret)
*res = -(*res);
} else {
ret = strict_strtoull(cp, base, (unsigned long long *)res);
}
return ret;
}
EXPORT_SYMBOL(strict_strtoll);
static int skip_atoi(const char **s)
{
int i = 0;
while (isdigit(**s))
i = i*10 + *((*s)++) - '0';
return i;
}
/* Decimal conversion is by far the most typical, and is used
* for /proc and /sys data. This directly impacts e.g. top performance
* with many processes running. We optimize it for speed
* using code from
* http://www.cs.uiowa.edu/~jones/bcd/decimal.html
* (with permission from the author, Douglas W. Jones). */
/* Formats correctly any integer in [0,99999].
* Outputs from one to five digits depending on input.
* On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
static char *put_dec_trunc(char *buf, unsigned q)
{
unsigned d3, d2, d1, d0;
d1 = (q>>4) & 0xf;
d2 = (q>>8) & 0xf;
d3 = (q>>12);
d0 = 6*(d3 + d2 + d1) + (q & 0xf);
q = (d0 * 0xcd) >> 11;
d0 = d0 - 10*q;
*buf++ = d0 + '0'; /* least significant digit */
d1 = q + 9*d3 + 5*d2 + d1;
if (d1 != 0) {
q = (d1 * 0xcd) >> 11;
d1 = d1 - 10*q;
*buf++ = d1 + '0'; /* next digit */
d2 = q + 2*d2;
if ((d2 != 0) || (d3 != 0)) {
q = (d2 * 0xd) >> 7;
d2 = d2 - 10*q;
*buf++ = d2 + '0'; /* next digit */
d3 = q + 4*d3;
if (d3 != 0) {
q = (d3 * 0xcd) >> 11;
d3 = d3 - 10*q;
*buf++ = d3 + '0'; /* next digit */
if (q != 0)
*buf++ = q + '0'; /* most sign. digit */
}
}
}
return buf;
}
/* Same with if's removed. Always emits five digits */
static char *put_dec_full(char *buf, unsigned q)
{
/* BTW, if q is in [0,9999], 8-bit ints will be enough, */
/* but anyway, gcc produces better code with full-sized ints */
unsigned d3, d2, d1, d0;
d1 = (q>>4) & 0xf;
d2 = (q>>8) & 0xf;
d3 = (q>>12);
/*
* Possible ways to approx. divide by 10
* gcc -O2 replaces multiply with shifts and adds
* (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
* (x * 0x67) >> 10: 1100111
* (x * 0x34) >> 9: 110100 - same
* (x * 0x1a) >> 8: 11010 - same
* (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
*/
d0 = 6*(d3 + d2 + d1) + (q & 0xf);
q = (d0 * 0xcd) >> 11;
d0 = d0 - 10*q;
*buf++ = d0 + '0';
d1 = q + 9*d3 + 5*d2 + d1;
q = (d1 * 0xcd) >> 11;
d1 = d1 - 10*q;
*buf++ = d1 + '0';
d2 = q + 2*d2;
q = (d2 * 0xd) >> 7;
d2 = d2 - 10*q;
*buf++ = d2 + '0';
d3 = q + 4*d3;
q = (d3 * 0xcd) >> 11; /* - shorter code */
/* q = (d3 * 0x67) >> 10; - would also work */
d3 = d3 - 10*q;
*buf++ = d3 + '0';
*buf++ = q + '0';
return buf;
}
/* No inlining helps gcc to use registers better */
static noinline char *put_dec(char *buf, unsigned long long num)
{
while (1) {
unsigned rem;
if (num < 100000)
return put_dec_trunc(buf, num);
rem = do_div(num, 100000);
buf = put_dec_full(buf, rem);
}
}
#define ZEROPAD 1 /* pad with zero */
#define SIGN 2 /* unsigned/signed long */
#define PLUS 4 /* show plus */
#define SPACE 8 /* space if plus */
#define LEFT 16 /* left justified */
#define SMALL 32 /* Must be 32 == 0x20 */
#define SPECIAL 64 /* 0x */
enum format_type {
FORMAT_TYPE_NONE, /* Just a string part */
FORMAT_TYPE_WIDTH,
FORMAT_TYPE_PRECISION,
FORMAT_TYPE_CHAR,
FORMAT_TYPE_STR,
FORMAT_TYPE_PTR,
FORMAT_TYPE_PERCENT_CHAR,
FORMAT_TYPE_INVALID,
FORMAT_TYPE_LONG_LONG,
FORMAT_TYPE_ULONG,
FORMAT_TYPE_LONG,
FORMAT_TYPE_UBYTE,
FORMAT_TYPE_BYTE,
FORMAT_TYPE_USHORT,
FORMAT_TYPE_SHORT,
FORMAT_TYPE_UINT,
FORMAT_TYPE_INT,
FORMAT_TYPE_NRCHARS,
FORMAT_TYPE_SIZE_T,
FORMAT_TYPE_PTRDIFF
};
struct printf_spec {
enum format_type type;
int flags; /* flags to number() */
int field_width; /* width of output field */
int base;
int precision; /* # of digits/chars */
int qualifier;
};
static char *number(char *buf, char *end, unsigned long long num,
struct printf_spec spec)
{
/* we are called with base 8, 10 or 16, only, thus don't need "G..." */
static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
char tmp[66];
char sign;
char locase;
int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
int i;
/* locase = 0 or 0x20. ORing digits or letters with 'locase'
* produces same digits or (maybe lowercased) letters */
locase = (spec.flags & SMALL);
if (spec.flags & LEFT)
spec.flags &= ~ZEROPAD;
sign = 0;
if (spec.flags & SIGN) {
if ((signed long long)num < 0) {
sign = '-';
num = -(signed long long)num;
spec.field_width--;
} else if (spec.flags & PLUS) {
sign = '+';
spec.field_width--;
} else if (spec.flags & SPACE) {
sign = ' ';
spec.field_width--;
}
}
if (need_pfx) {
spec.field_width--;
if (spec.base == 16)
spec.field_width--;
}
/* generate full string in tmp[], in reverse order */
i = 0;
if (num == 0)
tmp[i++] = '0';
/* Generic code, for any base:
else do {
tmp[i++] = (digits[do_div(num,base)] | locase);
} while (num != 0);
*/
else if (spec.base != 10) { /* 8 or 16 */
int mask = spec.base - 1;
int shift = 3;
if (spec.base == 16)
shift = 4;
do {
tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
num >>= shift;
} while (num);
} else { /* base 10 */
i = put_dec(tmp, num) - tmp;
}
/* printing 100 using %2d gives "100", not "00" */
if (i > spec.precision)
spec.precision = i;
/* leading space padding */
spec.field_width -= spec.precision;
if (!(spec.flags & (ZEROPAD+LEFT))) {
while (--spec.field_width >= 0) {
if (buf < end)
*buf = ' ';
++buf;
}
}
/* sign */
if (sign) {
if (buf < end)
*buf = sign;
++buf;
}
/* "0x" / "0" prefix */
if (need_pfx) {
if (buf < end)
*buf = '0';
++buf;
if (spec.base == 16) {
if (buf < end)
*buf = ('X' | locase);
++buf;
}
}
/* zero or space padding */
if (!(spec.flags & LEFT)) {
char c = (spec.flags & ZEROPAD) ? '0' : ' ';
while (--spec.field_width >= 0) {
if (buf < end)
*buf = c;
++buf;
}
}
/* hmm even more zero padding? */
while (i <= --spec.precision) {
if (buf < end)
*buf = '0';
++buf;
}
/* actual digits of result */
while (--i >= 0) {
if (buf < end)
*buf = tmp[i];
++buf;
}
/* trailing space padding */
while (--spec.field_width >= 0) {
if (buf < end)
*buf = ' ';
++buf;
}
return buf;
}
static char *string(char *buf, char *end, const char *s, struct printf_spec spec)
{
int len, i;
if ((unsigned long)s < PAGE_SIZE)
s = "(null)";
len = strnlen(s, spec.precision);
if (!(spec.flags & LEFT)) {
while (len < spec.field_width--) {
if (buf < end)
*buf = ' ';
++buf;
}
}
for (i = 0; i < len; ++i) {
if (buf < end)
*buf = *s;
++buf; ++s;
}
while (len < spec.field_width--) {
if (buf < end)
*buf = ' ';
++buf;
}
return buf;
}
static char *symbol_string(char *buf, char *end, void *ptr,
struct printf_spec spec, char ext)
{
unsigned long value = (unsigned long) ptr;
#ifdef CONFIG_KALLSYMS
char sym[KSYM_SYMBOL_LEN];
if (ext != 'f' && ext != 's')
sprint_symbol(sym, value);
else
kallsyms_lookup(value, NULL, NULL, NULL, sym);
return string(buf, end, sym, spec);
#else
spec.field_width = 2 * sizeof(void *);
spec.flags |= SPECIAL | SMALL | ZEROPAD;
spec.base = 16;
return number(buf, end, value, spec);
#endif
}
static char *resource_string(char *buf, char *end, struct resource *res,
struct printf_spec spec, const char *fmt)
{
#ifndef IO_RSRC_PRINTK_SIZE
#define IO_RSRC_PRINTK_SIZE 6
#endif
#ifndef MEM_RSRC_PRINTK_SIZE
#define MEM_RSRC_PRINTK_SIZE 10
#endif
struct printf_spec hex_spec = {
.base = 16,
.precision = -1,
.flags = SPECIAL | SMALL | ZEROPAD,
};
struct printf_spec dec_spec = {
.base = 10,
.precision = -1,
.flags = 0,
};
struct printf_spec str_spec = {
.field_width = -1,
.precision = 10,
.flags = LEFT,
};
struct printf_spec flag_spec = {
.base = 16,
.precision = -1,
.flags = SPECIAL | SMALL,
};
/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
* 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref disabled]")
#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
char *p = sym, *pend = sym + sizeof(sym);
int size = -1, addr = 0;
int decode = (fmt[0] == 'R') ? 1 : 0;
if (res->flags & IORESOURCE_IO) {
size = IO_RSRC_PRINTK_SIZE;
addr = 1;
} else if (res->flags & IORESOURCE_MEM) {
size = MEM_RSRC_PRINTK_SIZE;
addr = 1;
}
*p++ = '[';
if (res->flags & IORESOURCE_IO)
p = string(p, pend, "io ", str_spec);
else if (res->flags & IORESOURCE_MEM)
p = string(p, pend, "mem ", str_spec);
else if (res->flags & IORESOURCE_IRQ)
p = string(p, pend, "irq ", str_spec);
else if (res->flags & IORESOURCE_DMA)
p = string(p, pend, "dma ", str_spec);
else {
p = string(p, pend, "??? ", str_spec);
decode = 0;
}
hex_spec.field_width = size;
p = number(p, pend, res->start, addr ? hex_spec : dec_spec);
if (res->start != res->end) {
*p++ = '-';
p = number(p, pend, res->end, addr ? hex_spec : dec_spec);
}
if (decode) {
if (res->flags & IORESOURCE_MEM_64)
p = string(p, pend, " 64bit", str_spec);
if (res->flags & IORESOURCE_PREFETCH)
p = string(p, pend, " pref", str_spec);
if (res->flags & IORESOURCE_DISABLED)
p = string(p, pend, " disabled", str_spec);
} else {
p = string(p, pend, " flags ", str_spec);
p = number(p, pend, res->flags, flag_spec);
}
*p++ = ']';
*p = '\0';
return string(buf, end, sym, spec);
}
static char *mac_address_string(char *buf, char *end, u8 *addr,
struct printf_spec spec, const char *fmt)
{
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 (fmt[0] == 'M' && i != 5)
*p++ = ':';
}
*p = '\0';
return string(buf, end, mac_addr, 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 char *addr)
{
int i, j, range;
unsigned char zerolength[8];
int longest = 1;
int colonpos = -1;
u16 word;
u8 hi, lo;
bool needcolon = false;
bool useIPv4;
struct in6_addr in6;
memcpy(&in6, addr, sizeof(struct in6_addr));
useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
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 (in6.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(in6.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);
p = pack_hex_byte(p, lo);
}
else if (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, &in6.s6_addr[12], false);
}
*p = '\0';
return p;
}
static char *ip6_string(char *p, const char *addr, const char *fmt)
{
int i;
for (i = 0; i < 8; i++) {
p = pack_hex_byte(p, *addr++);
p = pack_hex_byte(p, *addr++);
if (fmt[0] == 'I' && i != 7)
*p++ = ':';
}
*p = '\0';
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, addr);
else
ip6_string(ip6_addr, addr, fmt);
return string(buf, end, ip6_addr, spec);
}
static char *ip4_addr_string(char *buf, char *end, const u8 *addr,
struct printf_spec spec, const char *fmt)
{
char ip4_addr[sizeof("255.255.255.255")];
ip4_string(ip4_addr, addr, fmt[0] == 'i');
return string(buf, end, ip4_addr, spec);
}
/*
* Show a '%p' thing. A kernel extension is that the '%p' is followed
* by an extra set of alphanumeric characters that are extended format
* specifiers.
*
* Right now we handle:
*
* - 'F' For symbolic function descriptor pointers with offset
* - 'f' For simple symbolic function names without offset
* - 'S' For symbolic direct pointers with offset
* - 's' For symbolic direct pointers without offset
* - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
* - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
* - 'M' For a 6-byte MAC address, it prints the address in the
* usual colon-separated hex notation
* - '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.
*/
static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
struct printf_spec spec)
{
if (!ptr)
return string(buf, end, "(null)", spec);
switch (*fmt) {
case 'F':
case 'f':
ptr = dereference_function_descriptor(ptr);
/* Fallthrough */
case 's':
case 'S':
return symbol_string(buf, end, ptr, spec, *fmt);
case 'R':
case 'r':
return resource_string(buf, end, ptr, spec, fmt);
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;
if (spec.field_width == -1) {
spec.field_width = 2*sizeof(void *);
spec.flags |= ZEROPAD;
}
spec.base = 16;
return number(buf, end, (unsigned long) ptr, spec);
}
/*
* Helper function to decode printf style format.
* Each call decode a token from the format and return the
* number of characters read (or likely the delta where it wants
* to go on the next call).
* The decoded token is returned through the parameters
*
* 'h', 'l', or 'L' for integer fields
* 'z' support added 23/7/1999 S.H.
* 'z' changed to 'Z' --davidm 1/25/99
* 't' added for ptrdiff_t
*
* @fmt: the format string
* @type of the token returned
* @flags: various flags such as +, -, # tokens..
* @field_width: overwritten width
* @base: base of the number (octal, hex, ...)
* @precision: precision of a number
* @qualifier: qualifier of a number (long, size_t, ...)
*/
static int format_decode(const char *fmt, struct printf_spec *spec)
{
const char *start = fmt;
/* we finished early by reading the field width */
if (spec->type == FORMAT_TYPE_WIDTH) {
if (spec->field_width < 0) {
spec->field_width = -spec->field_width;
spec->flags |= LEFT;
}
spec->type = FORMAT_TYPE_NONE;
goto precision;
}
/* we finished early by reading the precision */
if (spec->type == FORMAT_TYPE_PRECISION) {
if (spec->precision < 0)
spec->precision = 0;
spec->type = FORMAT_TYPE_NONE;
goto qualifier;
}
/* By default */
spec->type = FORMAT_TYPE_NONE;
for (; *fmt ; ++fmt) {
if (*fmt == '%')
break;
}
/* Return the current non-format string */
if (fmt != start || !*fmt)
return fmt - start;
/* Process flags */
spec->flags = 0;
while (1) { /* this also skips first '%' */
bool found = true;
++fmt;
switch (*fmt) {
case '-': spec->flags |= LEFT; break;
case '+': spec->flags |= PLUS; break;
case ' ': spec->flags |= SPACE; break;
case '#': spec->flags |= SPECIAL; break;
case '0': spec->flags |= ZEROPAD; break;
default: found = false;
}
if (!found)
break;
}
/* get field width */
spec->field_width = -1;
if (isdigit(*fmt))
spec->field_width = skip_atoi(&fmt);
else if (*fmt == '*') {
/* it's the next argument */
spec->type = FORMAT_TYPE_WIDTH;
return ++fmt - start;
}
precision:
/* get the precision */
spec->precision = -1;
if (*fmt == '.') {
++fmt;
if (isdigit(*fmt)) {
spec->precision = skip_atoi(&fmt);
if (spec->precision < 0)
spec->precision = 0;
} else if (*fmt == '*') {
/* it's the next argument */
spec->type = FORMAT_TYPE_PRECISION;
return ++fmt - start;
}
}
qualifier:
/* get the conversion qualifier */
spec->qualifier = -1;
if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
TOLOWER(*fmt) == 'z' || *fmt == 't') {
spec->qualifier = *fmt++;
if (unlikely(spec->qualifier == *fmt)) {
if (spec->qualifier == 'l') {
spec->qualifier = 'L';
++fmt;
} else if (spec->qualifier == 'h') {
spec->qualifier = 'H';
++fmt;
}
}
}
/* default base */
spec->base = 10;
switch (*fmt) {
case 'c':
spec->type = FORMAT_TYPE_CHAR;
return ++fmt - start;
case 's':
spec->type = FORMAT_TYPE_STR;
return ++fmt - start;
case 'p':
spec->type = FORMAT_TYPE_PTR;
return fmt - start;
/* skip alnum */
case 'n':
spec->type = FORMAT_TYPE_NRCHARS;
return ++fmt - start;
case '%':
spec->type = FORMAT_TYPE_PERCENT_CHAR;
return ++fmt - start;
/* integer number formats - set up the flags and "break" */
case 'o':
spec->base = 8;
break;
case 'x':
spec->flags |= SMALL;
case 'X':
spec->base = 16;
break;
case 'd':
case 'i':
spec->flags |= SIGN;
case 'u':
break;
default:
spec->type = FORMAT_TYPE_INVALID;
return fmt - start;
}
if (spec->qualifier == 'L')
spec->type = FORMAT_TYPE_LONG_LONG;
else if (spec->qualifier == 'l') {
if (spec->flags & SIGN)
spec->type = FORMAT_TYPE_LONG;
else
spec->type = FORMAT_TYPE_ULONG;
} else if (TOLOWER(spec->qualifier) == 'z') {
spec->type = FORMAT_TYPE_SIZE_T;
} else if (spec->qualifier == 't') {
spec->type = FORMAT_TYPE_PTRDIFF;
} else if (spec->qualifier == 'H') {
if (spec->flags & SIGN)
spec->type = FORMAT_TYPE_BYTE;
else
spec->type = FORMAT_TYPE_UBYTE;
} else if (spec->qualifier == 'h') {
if (spec->flags & SIGN)
spec->type = FORMAT_TYPE_SHORT;
else
spec->type = FORMAT_TYPE_USHORT;
} else {
if (spec->flags & SIGN)
spec->type = FORMAT_TYPE_INT;
else
spec->type = FORMAT_TYPE_UINT;
}
return ++fmt - start;
}
/**
* vsnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* This function follows C99 vsnprintf, but has some extensions:
* %pS output the name of a text symbol with offset
* %ps output the name of a text symbol without offset
* %pF output the name of a function pointer with its offset
* %pf output the name of a function pointer without its offset
* %pR output the address range in a struct resource
* %n is ignored
*
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing
* '\0', as per ISO C99. If you want to have the exact
* number of characters written into @buf as return value
* (not including the trailing '\0'), use vscnprintf(). If the
* return is greater than or equal to @size, the resulting
* string is truncated.
*
* Call this function if you are already dealing with a va_list.
* You probably want snprintf() instead.
*/
int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
unsigned long long num;
char *str, *end;
struct printf_spec spec = {0};
/* Reject out-of-range values early. Large positive sizes are
used for unknown buffer sizes. */
if (WARN_ON_ONCE((int) size < 0))
return 0;
str = buf;
end = buf + size;
/* Make sure end is always >= buf */
if (end < buf) {
end = ((void *)-1);
size = end - buf;
}
while (*fmt) {
const char *old_fmt = fmt;
int read = format_decode(fmt, &spec);
fmt += read;
switch (spec.type) {
case FORMAT_TYPE_NONE: {
int copy = read;
if (str < end) {
if (copy > end - str)
copy = end - str;
memcpy(str, old_fmt, copy);
}
str += read;
break;
}
case FORMAT_TYPE_WIDTH:
spec.field_width = va_arg(args, int);
break;
case FORMAT_TYPE_PRECISION:
spec.precision = va_arg(args, int);
break;
case FORMAT_TYPE_CHAR: {
char c;
if (!(spec.flags & LEFT)) {
while (--spec.field_width > 0) {
if (str < end)
*str = ' ';
++str;
}
}
c = (unsigned char) va_arg(args, int);
if (str < end)
*str = c;
++str;
while (--spec.field_width > 0) {
if (str < end)
*str = ' ';
++str;
}
break;
}
case FORMAT_TYPE_STR:
str = string(str, end, va_arg(args, char *), spec);
break;
case FORMAT_TYPE_PTR:
str = pointer(fmt+1, str, end, va_arg(args, void *),
spec);
while (isalnum(*fmt))
fmt++;
break;
case FORMAT_TYPE_PERCENT_CHAR:
if (str < end)
*str = '%';
++str;
break;
case FORMAT_TYPE_INVALID:
if (str < end)
*str = '%';
++str;
break;
case FORMAT_TYPE_NRCHARS: {
int qualifier = spec.qualifier;
if (qualifier == 'l') {
long *ip = va_arg(args, long *);
*ip = (str - buf);
} else if (TOLOWER(qualifier) == 'z') {
size_t *ip = va_arg(args, size_t *);
*ip = (str - buf);
} else {
int *ip = va_arg(args, int *);
*ip = (str - buf);
}
break;
}
default:
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
num = va_arg(args, long long);
break;
case FORMAT_TYPE_ULONG:
num = va_arg(args, unsigned long);
break;
case FORMAT_TYPE_LONG:
num = va_arg(args, long);
break;
case FORMAT_TYPE_SIZE_T:
num = va_arg(args, size_t);
break;
case FORMAT_TYPE_PTRDIFF:
num = va_arg(args, ptrdiff_t);
break;
case FORMAT_TYPE_UBYTE:
num = (unsigned char) va_arg(args, int);
break;
case FORMAT_TYPE_BYTE:
num = (signed char) va_arg(args, int);
break;
case FORMAT_TYPE_USHORT:
num = (unsigned short) va_arg(args, int);
break;
case FORMAT_TYPE_SHORT:
num = (short) va_arg(args, int);
break;
case FORMAT_TYPE_INT:
num = (int) va_arg(args, int);
break;
default:
num = va_arg(args, unsigned int);
}
str = number(str, end, num, spec);
}
}
if (size > 0) {
if (str < end)
*str = '\0';
else
end[-1] = '\0';
}
/* the trailing null byte doesn't count towards the total */
return str-buf;
}
EXPORT_SYMBOL(vsnprintf);
/**
* vscnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The return value is the number of characters which have been written into
* the @buf not including the trailing '\0'. If @size is <= 0 the function
* returns 0.
*
* Call this function if you are already dealing with a va_list.
* You probably want scnprintf() instead.
*
* See the vsnprintf() documentation for format string extensions over C99.
*/
int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
int i;
i = vsnprintf(buf, size, fmt, args);
return (i >= size) ? (size - 1) : i;
}
EXPORT_SYMBOL(vscnprintf);
/**
* snprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters which would be
* generated for the given input, excluding the trailing null,
* as per ISO C99. If the return is greater than or equal to
* @size, the resulting string is truncated.
*
* See the vsnprintf() documentation for format string extensions over C99.
*/
int snprintf(char *buf, size_t size, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i = vsnprintf(buf, size, fmt, args);
va_end(args);
return i;
}
EXPORT_SYMBOL(snprintf);
/**
* scnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The return value is the number of characters written into @buf not including
* the trailing '\0'. If @size is <= 0 the function returns 0.
*/
int scnprintf(char *buf, size_t size, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i = vsnprintf(buf, size, fmt, args);
va_end(args);
return (i >= size) ? (size - 1) : i;
}
EXPORT_SYMBOL(scnprintf);
/**
* vsprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The function returns the number of characters written
* into @buf. Use vsnprintf() or vscnprintf() in order to avoid
* buffer overflows.
*
* Call this function if you are already dealing with a va_list.
* You probably want sprintf() instead.
*
* See the vsnprintf() documentation for format string extensions over C99.
*/
int vsprintf(char *buf, const char *fmt, va_list args)
{
return vsnprintf(buf, INT_MAX, fmt, args);
}
EXPORT_SYMBOL(vsprintf);
/**
* sprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The function returns the number of characters written
* into @buf. Use snprintf() or scnprintf() in order to avoid
* buffer overflows.
*
* See the vsnprintf() documentation for format string extensions over C99.
*/
int sprintf(char *buf, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i = vsnprintf(buf, INT_MAX, fmt, args);
va_end(args);
return i;
}
EXPORT_SYMBOL(sprintf);
#ifdef CONFIG_BINARY_PRINTF
/*
* bprintf service:
* vbin_printf() - VA arguments to binary data
* bstr_printf() - Binary data to text string
*/
/**
* vbin_printf - Parse a format string and place args' binary value in a buffer
* @bin_buf: The buffer to place args' binary value
* @size: The size of the buffer(by words(32bits), not characters)
* @fmt: The format string to use
* @args: Arguments for the format string
*
* The format follows C99 vsnprintf, except %n is ignored, and its argument
* is skiped.
*
* The return value is the number of words(32bits) which would be generated for
* the given input.
*
* NOTE:
* If the return value is greater than @size, the resulting bin_buf is NOT
* valid for bstr_printf().
*/
int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
{
struct printf_spec spec = {0};
char *str, *end;
str = (char *)bin_buf;
end = (char *)(bin_buf + size);
#define save_arg(type) \
do { \
if (sizeof(type) == 8) { \
unsigned long long value; \
str = PTR_ALIGN(str, sizeof(u32)); \
value = va_arg(args, unsigned long long); \
if (str + sizeof(type) <= end) { \
*(u32 *)str = *(u32 *)&value; \
*(u32 *)(str + 4) = *((u32 *)&value + 1); \
} \
} else { \
unsigned long value; \
str = PTR_ALIGN(str, sizeof(type)); \
value = va_arg(args, int); \
if (str + sizeof(type) <= end) \
*(typeof(type) *)str = (type)value; \
} \
str += sizeof(type); \
} while (0)
while (*fmt) {
int read = format_decode(fmt, &spec);
fmt += read;
switch (spec.type) {
case FORMAT_TYPE_NONE:
case FORMAT_TYPE_INVALID:
case FORMAT_TYPE_PERCENT_CHAR:
break;
case FORMAT_TYPE_WIDTH:
case FORMAT_TYPE_PRECISION:
save_arg(int);
break;
case FORMAT_TYPE_CHAR:
save_arg(char);
break;
case FORMAT_TYPE_STR: {
const char *save_str = va_arg(args, char *);
size_t len;
if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
|| (unsigned long)save_str < PAGE_SIZE)
save_str = "(null)";
len = strlen(save_str) + 1;
if (str + len < end)
memcpy(str, save_str, len);
str += len;
break;
}
case FORMAT_TYPE_PTR:
save_arg(void *);
/* skip all alphanumeric pointer suffixes */
while (isalnum(*fmt))
fmt++;
break;
case FORMAT_TYPE_NRCHARS: {
/* skip %n 's argument */
int qualifier = spec.qualifier;
void *skip_arg;
if (qualifier == 'l')
skip_arg = va_arg(args, long *);
else if (TOLOWER(qualifier) == 'z')
skip_arg = va_arg(args, size_t *);
else
skip_arg = va_arg(args, int *);
break;
}
default:
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
save_arg(long long);
break;
case FORMAT_TYPE_ULONG:
case FORMAT_TYPE_LONG:
save_arg(unsigned long);
break;
case FORMAT_TYPE_SIZE_T:
save_arg(size_t);
break;
case FORMAT_TYPE_PTRDIFF:
save_arg(ptrdiff_t);
break;
case FORMAT_TYPE_UBYTE:
case FORMAT_TYPE_BYTE:
save_arg(char);
break;
case FORMAT_TYPE_USHORT:
case FORMAT_TYPE_SHORT:
save_arg(short);
break;
default:
save_arg(int);
}
}
}
return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
#undef save_arg
}
EXPORT_SYMBOL_GPL(vbin_printf);
/**
* bstr_printf - Format a string from binary arguments and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @bin_buf: Binary arguments for the format string
*
* This function like C99 vsnprintf, but the difference is that vsnprintf gets
* arguments from stack, and bstr_printf gets arguments from @bin_buf which is
* a binary buffer that generated by vbin_printf.
*
* The format follows C99 vsnprintf, but has some extensions:
* see vsnprintf comment for details.
*
* The return value is the number of characters which would
* be generated for the given input, excluding the trailing
* '\0', as per ISO C99. If you want to have the exact
* number of characters written into @buf as return value
* (not including the trailing '\0'), use vscnprintf(). If the
* return is greater than or equal to @size, the resulting
* string is truncated.
*/
int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
{
struct printf_spec spec = {0};
char *str, *end;
const char *args = (const char *)bin_buf;
if (WARN_ON_ONCE((int) size < 0))
return 0;
str = buf;
end = buf + size;
#define get_arg(type) \
({ \
typeof(type) value; \
if (sizeof(type) == 8) { \
args = PTR_ALIGN(args, sizeof(u32)); \
*(u32 *)&value = *(u32 *)args; \
*((u32 *)&value + 1) = *(u32 *)(args + 4); \
} else { \
args = PTR_ALIGN(args, sizeof(type)); \
value = *(typeof(type) *)args; \
} \
args += sizeof(type); \
value; \
})
/* Make sure end is always >= buf */
if (end < buf) {
end = ((void *)-1);
size = end - buf;
}
while (*fmt) {
const char *old_fmt = fmt;
int read = format_decode(fmt, &spec);
fmt += read;
switch (spec.type) {
case FORMAT_TYPE_NONE: {
int copy = read;
if (str < end) {
if (copy > end - str)
copy = end - str;
memcpy(str, old_fmt, copy);
}
str += read;
break;
}
case FORMAT_TYPE_WIDTH:
spec.field_width = get_arg(int);
break;
case FORMAT_TYPE_PRECISION:
spec.precision = get_arg(int);
break;
case FORMAT_TYPE_CHAR: {
char c;
if (!(spec.flags & LEFT)) {
while (--spec.field_width > 0) {
if (str < end)
*str = ' ';
++str;
}
}
c = (unsigned char) get_arg(char);
if (str < end)
*str = c;
++str;
while (--spec.field_width > 0) {
if (str < end)
*str = ' ';
++str;
}
break;
}
case FORMAT_TYPE_STR: {
const char *str_arg = args;
args += strlen(str_arg) + 1;
str = string(str, end, (char *)str_arg, spec);
break;
}
case FORMAT_TYPE_PTR:
str = pointer(fmt+1, str, end, get_arg(void *), spec);
while (isalnum(*fmt))
fmt++;
break;
case FORMAT_TYPE_PERCENT_CHAR:
case FORMAT_TYPE_INVALID:
if (str < end)
*str = '%';
++str;
break;
case FORMAT_TYPE_NRCHARS:
/* skip */
break;
default: {
unsigned long long num;
switch (spec.type) {
case FORMAT_TYPE_LONG_LONG:
num = get_arg(long long);
break;
case FORMAT_TYPE_ULONG:
case FORMAT_TYPE_LONG:
num = get_arg(unsigned long);
break;
case FORMAT_TYPE_SIZE_T:
num = get_arg(size_t);
break;
case FORMAT_TYPE_PTRDIFF:
num = get_arg(ptrdiff_t);
break;
case FORMAT_TYPE_UBYTE:
num = get_arg(unsigned char);
break;
case FORMAT_TYPE_BYTE:
num = get_arg(signed char);
break;
case FORMAT_TYPE_USHORT:
num = get_arg(unsigned short);
break;
case FORMAT_TYPE_SHORT:
num = get_arg(short);
break;
case FORMAT_TYPE_UINT:
num = get_arg(unsigned int);
break;
default:
num = get_arg(int);
}
str = number(str, end, num, spec);
} /* default: */
} /* switch(spec.type) */
} /* while(*fmt) */
if (size > 0) {
if (str < end)
*str = '\0';
else
end[-1] = '\0';
}
#undef get_arg
/* the trailing null byte doesn't count towards the total */
return str - buf;
}
EXPORT_SYMBOL_GPL(bstr_printf);
/**
* bprintf - Parse a format string and place args' binary value in a buffer
* @bin_buf: The buffer to place args' binary value
* @size: The size of the buffer(by words(32bits), not characters)
* @fmt: The format string to use
* @...: Arguments for the format string
*
* The function returns the number of words(u32) written
* into @bin_buf.
*/
int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
{
va_list args;
int ret;
va_start(args, fmt);
ret = vbin_printf(bin_buf, size, fmt, args);
va_end(args);
return ret;
}
EXPORT_SYMBOL_GPL(bprintf);
#endif /* CONFIG_BINARY_PRINTF */
static noinline char *skip_space(const char *str)
{
while (isspace(*str))
++str;
return (char *)str;
}
/**
* vsscanf - Unformat a buffer into a list of arguments
* @buf: input buffer
* @fmt: format of buffer
* @args: arguments
*/
int vsscanf(const char *buf, const char *fmt, va_list args)
{
const char *str = buf;
char *next;
char digit;
int num = 0;
int qualifier, base, field_width;
bool is_sign;
while (*fmt && *str) {
/* skip any white space in format */
/* white space in format matchs any amount of
* white space, including none, in the input.
*/
if (isspace(*fmt)) {
fmt = skip_space(fmt);
str = skip_space(str);
}
/* anything that is not a conversion must match exactly */
if (*fmt != '%' && *fmt) {
if (*fmt++ != *str++)
break;
continue;
}
if (!*fmt)
break;
++fmt;
/* skip this conversion.
* advance both strings to next white space
*/
if (*fmt == '*') {
while (!isspace(*fmt) && *fmt != '%' && *fmt)
fmt++;
while (!isspace(*str) && *str)
str++;
continue;
}
/* get field width */
field_width = -1;
if (isdigit(*fmt))
field_width = skip_atoi(&fmt);
/* get conversion qualifier */
qualifier = -1;
if (*fmt == 'h' || TOLOWER(*fmt) == 'l' ||
TOLOWER(*fmt) == 'z') {
qualifier = *fmt++;
if (unlikely(qualifier == *fmt)) {
if (qualifier == 'h') {
qualifier = 'H';
fmt++;
} else if (qualifier == 'l') {
qualifier = 'L';
fmt++;
}
}
}
if (!*fmt || !*str)
break;
base = 10;
is_sign = 0;
switch (*fmt++) {
case 'c':
{
char *s = (char *)va_arg(args, char*);
if (field_width == -1)
field_width = 1;
do {
*s++ = *str++;
} while (--field_width > 0 && *str);
num++;
}
continue;
case 's':
{
char *s = (char *)va_arg(args, char *);
if (field_width == -1)
field_width = INT_MAX;
/* first, skip leading white space in buffer */
str = skip_space(str);
/* now copy until next white space */
while (*str && !isspace(*str) && field_width--)
*s++ = *str++;
*s = '\0';
num++;
}
continue;
case 'n':
/* return number of characters read so far */
{
int *i = (int *)va_arg(args, int*);
*i = str - buf;
}
continue;
case 'o':
base = 8;
break;
case 'x':
case 'X':
base = 16;
break;
case 'i':
base = 0;
case 'd':
is_sign = 1;
case 'u':
break;
case '%':
/* looking for '%' in str */
if (*str++ != '%')
return num;
continue;
default:
/* invalid format; stop here */
return num;
}
/* have some sort of integer conversion.
* first, skip white space in buffer.
*/
str = skip_space(str);
digit = *str;
if (is_sign && digit == '-')
digit = *(str + 1);
if (!digit
|| (base == 16 && !isxdigit(digit))
|| (base == 10 && !isdigit(digit))
|| (base == 8 && (!isdigit(digit) || digit > '7'))
|| (base == 0 && !isdigit(digit)))
break;
switch (qualifier) {
case 'H': /* that's 'hh' in format */
if (is_sign) {
signed char *s = (signed char *)va_arg(args, signed char *);
*s = (signed char)simple_strtol(str, &next, base);
} else {
unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
*s = (unsigned char)simple_strtoul(str, &next, base);
}
break;
case 'h':
if (is_sign) {
short *s = (short *)va_arg(args, short *);
*s = (short)simple_strtol(str, &next, base);
} else {
unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
*s = (unsigned short)simple_strtoul(str, &next, base);
}
break;
case 'l':
if (is_sign) {
long *l = (long *)va_arg(args, long *);
*l = simple_strtol(str, &next, base);
} else {
unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
*l = simple_strtoul(str, &next, base);
}
break;
case 'L':
if (is_sign) {
long long *l = (long long *)va_arg(args, long long *);
*l = simple_strtoll(str, &next, base);
} else {
unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
*l = simple_strtoull(str, &next, base);
}
break;
case 'Z':
case 'z':
{
size_t *s = (size_t *)va_arg(args, size_t *);
*s = (size_t)simple_strtoul(str, &next, base);
}
break;
default:
if (is_sign) {
int *i = (int *)va_arg(args, int *);
*i = (int)simple_strtol(str, &next, base);
} else {
unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
*i = (unsigned int)simple_strtoul(str, &next, base);
}
break;
}
num++;
if (!next)
break;
str = next;
}
/*
* Now we've come all the way through so either the input string or the
* format ended. In the former case, there can be a %n at the current
* position in the format that needs to be filled.
*/
if (*fmt == '%' && *(fmt + 1) == 'n') {
int *p = (int *)va_arg(args, int *);
*p = str - buf;
}
return num;
}
EXPORT_SYMBOL(vsscanf);
/**
* sscanf - Unformat a buffer into a list of arguments
* @buf: input buffer
* @fmt: formatting of buffer
* @...: resulting arguments
*/
int sscanf(const char *buf, const char *fmt, ...)
{
va_list args;
int i;
va_start(args, fmt);
i = vsscanf(buf, fmt, args);
va_end(args);
return i;
}
EXPORT_SYMBOL(sscanf);