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bouwhuim.nikhef.nl dee2668a61 newest version WRPC
2013-09-10 08:08:59 +00:00

70 lines
1.3 KiB
C

#include <stdarg.h>
/*
* minimal vsprintf: only %s and hex values
* Alessandro Rubini 2010, based on code in u-boot (from older Linux)
* GNU GPL version 2.
*/
int pp_vsprintf(char *buf, const char *fmt, va_list args)
{
int i, j;
static char hex[] = "0123456789abcdef";
char *s;
char *str = buf;
for (; *fmt ; ++fmt) {
if (*fmt != '%') {
*str++ = *fmt;
continue;
}
repeat:
fmt++; /* Skip '%' initially, other stuff later */
/* Skip the complete format string */
switch(*fmt) {
case '\0':
goto ret;
case '*':
/* should be precision, just eat it */
i = va_arg(args, int);
/* fall through: discard unknown stuff */
default:
goto repeat;
/* Special cases for conversions */
case 'c': /* char: supported */
*str++ = (unsigned char) va_arg(args, int);
break;
case 's': /* string: supported */
s = va_arg(args, char *);
while (*s)
*str++ = *s++;
break;
case 'n': /* number-thus-far: not supported */
break;
case '%': /* supported */
*str++ = '%';
break;
/* all integer (and pointer) are printed as <%08x> */
case 'o':
case 'x':
case 'X':
case 'd':
case 'i':
case 'u':
case 'p':
i = va_arg(args, int);
*str++ = '<';
for (j = 28; j >= 0; j -= 4)
*str++ = hex[(i>>j)&0xf];
*str++ = '>';
break;
}
}
ret:
*str = '\0';
return str - buf;
}