?? vsprintf.c
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/*
* linux/lib/vsprintf.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
/*
* Wirzenius wrote this portably, Torvalds fucked it up :-)
*/
#include <stdarg.h>
//#include <linux/types.h>
#include <string.h>
#include <ctype.h>
unsigned long simple_strtoul( const char* cp , char** endp , unsigned int base )
{
unsigned long result = 0,value;
if ( *cp == '0' )
{
cp++;
if ( ( *cp == 'x' ) && isxdigit( cp[1] ) )
{
base = 16;
cp++;
}
if ( !base )
{
base = 8;
}
}
if ( !base )
{
base = 10;
}
while ( isxdigit( *cp ) &&
( value = isdigit( *cp ) ? *cp - '0' : ( islower( *cp ) ? toupper( *cp ) : *cp ) - 'A' + 10 ) < base )
{
result = result * base + value;
cp++;
}
if ( endp )
*endp = ( char * ) cp;
return result;
}
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 );
}
/* we use this so that we can do without the ctype library */
#define is_digit(c) ((c) >= '0' && (c) <= '9')
static int skip_atoi( const char** s )
{
int i = 0;
while ( is_digit( **s ) )
i = i * 10 + *( ( *s )++ ) - '0';
return i;
}
#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 SPECIAL 32 /* 0x */
#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
#define do_div(n,base) ({ \
int __res; \
__res = ((unsigned long) n) % (unsigned) base; \
n = ((unsigned long) n) / (unsigned) base; \
__res; })
static char* number( char* str , long num , int base , int size , int precision , int type )
{
char c, sign, tmp[66];
const char* digits = "0123456789abcdefghijklmnopqrstuvwxyz";
int i;
if ( type & LARGE )
digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if ( type & LEFT )
type &= ~ZEROPAD;
if ( base <2 || base> 36 )
return 0;
c = ( type & ZEROPAD ) ? '0' : ' ';
sign = 0;
if ( type & SIGN )
{
if ( num < 0 )
{
sign = '-';
num = -num;
size--;
}
else if ( type & PLUS )
{
sign = '+';
size--;
}
else if ( type & SPACE )
{
sign = ' ';
size--;
}
}
if ( type & SPECIAL )
{
if ( base == 16 )
size -= 2;
else if ( base == 8 )
size--;
}
i = 0;
if ( num == 0 )
tmp[i++] = '0';
else
while ( num != 0 )
{
int __res;
__res = ( ( unsigned long ) num ) % ( unsigned ) base;
num = ( ( unsigned long ) num ) / ( unsigned ) base;
tmp[i++] = digits[__res];
// tmp[i++] = digits[do_div(num,base)];
}
if ( i > precision )
precision = i;
size -= precision;
if ( !( type & ( ZEROPAD + LEFT ) ) )
while ( size-- > 0 )
*str++ = ' ';
if ( sign )
*str++ = sign;
if ( type & SPECIAL )
{
if ( base == 8 )
*str++ = '0';
else if ( base == 16 )
{
*str++ = '0';
*str++ = digits[33];
}
}
if ( !( type & LEFT ) )
while ( size-- > 0 )
*str++ = c;
while ( i < precision-- )
*str++ = '0';
while ( i-- > 0 )
*str++ = tmp[i];
while ( size-- > 0 )
*str++ = ' ';
return str;
}
/* Forward decl. needed for IP address printing stuff... */
int sprintf( char* buf , const char* fmt , ... );
int vsprintf( char* buf , const char* fmt , va_list args )
{
int len;
unsigned long num;
int i, base;
char* str;
const char* s;
int flags; /* flags to number() */
int field_width; /* width of output field */
int precision; /* min. # of digits for integers; max
number of chars for from string */
int qualifier; /* 'h', 'l', or 'L' for integer fields */
for ( str = buf ; *fmt ; ++fmt )
{
if ( *fmt != '%' )
{
*str++ = *fmt;
continue;
}
/* process flags */
flags = 0;
repeat:
++fmt; /* this also skips first '%' */
switch ( *fmt )
{
case '-':
flags |= LEFT; goto repeat;
case '+':
flags |= PLUS; goto repeat;
case ' ':
flags |= SPACE; goto repeat;
case '#':
flags |= SPECIAL; goto repeat;
case '0':
flags |= ZEROPAD; goto repeat;
}
/* get field width */
field_width = -1;
if ( is_digit( *fmt ) )
field_width = skip_atoi( &fmt );
else if ( *fmt == '*' )
{
++fmt;
/* it's the next argument */
field_width = va_arg( args , int );
if ( field_width < 0 )
{
field_width = -field_width;
flags |= LEFT;
}
}
/* get the precision */
precision = -1;
if ( *fmt == '.' )
{
++fmt;
if ( is_digit( *fmt ) )
precision = skip_atoi( &fmt );
else if ( *fmt == '*' )
{
++fmt;
/* it's the next argument */
precision = va_arg( args , int );
}
if ( precision < 0 )
precision = 0;
}
/* get the conversion qualifier */
qualifier = -1;
if ( *fmt == 'h' || *fmt == 'l' || *fmt == 'L' )
{
qualifier = *fmt;
++fmt;
}
/* default base */
base = 10;
switch ( *fmt )
{
case 'c':
if ( !( flags & LEFT ) )
while ( --field_width > 0 )
*str++ = ' ';
*str++ = ( unsigned char ) va_arg( args , int );
while ( --field_width > 0 )
*str++ = ' ';
continue;
case 's':
s = va_arg( args , char * );
if ( !s )
s = "<NULL>";
len = strnlen( s , precision );
if ( !( flags & LEFT ) )
while ( len < field_width-- )
*str++ = ' ';
for ( i = 0; i < len; ++i )
*str++ = *s++;
while ( len < field_width-- )
*str++ = ' ';
continue;
case 'p':
if ( field_width == -1 )
{
field_width = 2 * sizeof( void * );
flags |= ZEROPAD;
}
str = number( str , ( unsigned long ) va_arg( args , void * ) , 16 , field_width , precision , flags );
continue;
case 'n':
if ( qualifier == 'l' )
{
long* ip = va_arg( args , long* );
*ip = ( str - buf );
}
else
{
int* ip = va_arg( args , int* );
*ip = ( str - buf );
}
continue;
case '%':
*str++ = '%';
continue;
/* integer number formats - set up the flags and "break" */
case 'o':
base = 8;
break;
case 'X':
flags |= LARGE;
case 'x':
base = 16;
break;
case 'd':
case 'i':
flags |= SIGN;
case 'u':
break;
default:
*str++ = '%';
if ( *fmt )
*str++ = *fmt;
else
--fmt;
continue;
}
if ( qualifier == 'l' )
num = va_arg( args , unsigned long );
else if ( qualifier == 'h' )
{
num = ( unsigned short ) va_arg( args , int );
if ( flags & SIGN )
num = ( short ) num;
}
else if ( flags & SIGN )
num = va_arg( args , int );
else
num = va_arg( args , unsigned int );
str = number( str , num , base , field_width , precision , flags );
}
*str = '\0';
return str - buf;
}
int sprintf( char* buf , const char* fmt , ... )
{
va_list args;
int i;
va_start( args , fmt );
i = vsprintf( buf , fmt , args );
va_end( args );
return i;
}
/*
void panic(const char *fmt, ...)
{
va_list args;
va_start(args, fmt);
printf(fmt);
putc('\n');
va_end(args);
#if defined (CONFIG_PANIC_HANG)
hang();
#else
udelay (100000); // allow messages to go out
do_reset (NULL, 0, 0, NULL);
#endif
}*/
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