ack/lang/cem/libcc.ansi/stdio/fltpr.c

180 lines
3.2 KiB
C

/*
* fltpr.c - print floating point numbers
*/
/* $Id$ */
#include <string.h>
#include <stdarg.h>
#include "loc_incl.h"
#ifndef ACKCONF_NO_STDIO_FLOAT
static char *
_pfloat(long double r, register char *s, int n, int flags)
{
register char *s1;
int sign, dp;
register int i;
s1 = _fcvt(r, n, &dp, &sign);
if (sign)
*s++ = '-';
else if (flags & FL_SIGN)
*s++ = '+';
else if (flags & FL_SPACE)
*s++ = ' ';
if (dp<=0)
*s++ = '0';
for (i=dp; i>0; i--)
if (*s1) *s++ = *s1++;
else *s++ = '0';
if (((i=n) > 0) || (flags & FL_ALT))
*s++ = '.';
while (++dp <= 0) {
if (--i<0)
break;
*s++ = '0';
}
while (--i >= 0)
if (*s1) *s++ = *s1++;
else *s++ = '0';
return s;
}
static char *
_pscien(long double r, register char *s, int n, int flags)
{
int sign, dp;
register char *s1;
s1 = _ecvt(r, n + 1, &dp, &sign);
if (sign)
*s++ = '-';
else if (flags & FL_SIGN)
*s++ = '+';
else if (flags & FL_SPACE)
*s++ = ' ';
*s++ = *s1++;
if ((n > 0) || (flags & FL_ALT))
*s++ = '.';
while (--n >= 0)
if (*s1) *s++ = *s1++;
else *s++ = '0';
*s++ = 'e';
if ( r != 0 ) --dp ;
if ( dp<0 ) {
*s++ = '-' ; dp= -dp ;
} else {
*s++ = '+' ;
}
if (dp >= 100) {
*s++ = '0' + (dp / 100);
dp %= 100;
}
*s++ = '0' + (dp/10);
*s++ = '0' + (dp%10);
return s;
}
#define NDIGINEXP(exp) (((exp) >= 100 || (exp) <= -100) ? 3 : 2)
#define LOW_EXP -4
#define USE_EXP(exp, ndigits) (((exp) < LOW_EXP + 1) || (exp >= ndigits + 1))
static char *
_gcvt(long double value, int ndigit, char *s, int flags)
{
int sign, dp;
register char *s1, *s2;
register int i;
register int nndigit = ndigit;
s1 = _ecvt(value, ndigit, &dp, &sign);
s2 = s;
if (sign) *s2++ = '-';
else if (flags & FL_SIGN)
*s2++ = '+';
else if (flags & FL_SPACE)
*s2++ = ' ';
if (!(flags & FL_ALT))
for (i = nndigit - 1; i > 0 && s1[i] == '0'; i--)
nndigit--;
if (USE_EXP(dp,ndigit)) {
/* Use E format */
dp--;
*s2++ = *s1++;
if ((nndigit > 1) || (flags & FL_ALT)) *s2++ = '.';
while (--nndigit > 0) *s2++ = *s1++;
*s2++ = 'e';
if (dp < 0) {
*s2++ = '-';
dp = -dp;
}
else *s2++ = '+';
s2 += NDIGINEXP(dp);
*s2 = 0;
for (i = NDIGINEXP(dp); i > 0; i--) {
*--s2 = dp % 10 + '0';
dp /= 10;
}
return s;
}
/* Use f format */
if (dp <= 0) {
if (*s1 != '0') {
/* otherwise the whole number is 0 */
*s2++ = '0';
*s2++ = '.';
}
while (dp < 0) {
dp++;
*s2++ = '0';
}
}
for (i = 1; i <= nndigit; i++) {
*s2++ = *s1++;
if (i == dp) *s2++ = '.';
}
if (i <= dp) {
while (i++ <= dp) *s2++ = '0';
*s2++ = '.';
}
if ((s2[-1]=='.') && !(flags & FL_ALT)) s2--;
*s2 = '\0';
return s;
}
char *
_f_print(va_list *ap, int flags, char *s, char c, int precision)
{
register char *old_s = s;
long double ld_val;
if (flags & FL_LONGDOUBLE) ld_val = va_arg(*ap, long double);
else ld_val = (long double) va_arg(*ap, double);
switch(c) {
case 'f':
s = _pfloat(ld_val, s, precision, flags);
break;
case 'e':
case 'E':
s = _pscien(ld_val, s, precision , flags);
break;
case 'g':
case 'G':
s = _gcvt(ld_val, precision, s, flags);
s += strlen(s);
break;
}
if ( c == 'E' || c == 'G') {
while (*old_s && *old_s != 'e') old_s++;
if (*old_s == 'e') *old_s = 'E';
}
return s;
}
#endif /* ACKCONF_NO_STDIO_FLOAT */