static inline int
isdigit(int ch)
{
return (ch >= '0') && (ch <= '9');
}
unsigned int skip_atou(const char **s);
unsigned int atou(const char *s);
static int strnlen(const char *s, int maxlen)
{
const char *es = s;
while ( *es && maxlen ) {
es++; maxlen--;
}
return (es-s);
}
#define ZEROPAD 1
#define SIGN 2
#define PLUS 4
#define SPACE 8
#define LEFT 16
#define SPECIAL 32
#define LARGE 64
#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)
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;
}
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;
int field_width;
int precision;
int qualifier;
for (str=buf ; *fmt ; ++fmt) {
if (*fmt != '%') {
*str++ = *fmt;
continue;
}
flags = 0;
repeat:
++fmt;
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;
}
field_width = -1;
if (isdigit(*fmt))
field_width = skip_atou(&fmt);
else if (*fmt == '*') {
++fmt;
field_width = va_arg(args, int);
if (field_width < 0) {
field_width = -field_width;
flags |= LEFT;
}
}
precision = -1;
if (*fmt == '.') {
++fmt;
if (isdigit(*fmt))
precision = skip_atou(&fmt);
else if (*fmt == '*') {
++fmt;
precision = va_arg(args, int);
}
if (precision < 0)
precision = 0;
}
qualifier = -1;
if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L') {
qualifier = *fmt;
++fmt;
}
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 *);
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;
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;
}
int printf(const char *fmt, ...)
{
char printf_buf[1024];
va_list args;
int printed;
va_start(args, fmt);
printed = vsprintf(printf_buf, fmt, args);
va_end(args);
puts(printf_buf);
return printed;
}
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