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/*
* atolfp - convert an ascii string to an l_fp number
*/
#include <stdio.h>
#include <ctype.h>
#include "ntp_fp.h"
#include "ntp_string.h"
/*
* Powers of 10
*/
static u_long ten_to_the_n[10] = {
0,
10,
100,
1000,
10000,
100000,
1000000,
10000000,
100000000,
1000000000,
};
int
atolfp(str, lfp)
const char *str;
l_fp *lfp;
{
register const char *cp;
register u_long dec_i;
register u_long dec_f;
char *ind;
int ndec;
int isneg;
static char *digits = "0123456789";
isneg = 0;
dec_i = dec_f = 0;
ndec = 0;
cp = str;
/*
* We understand numbers of the form:
*
* [spaces][-|+][digits][.][digits][spaces|\n|\0]
*/
while (isspace(*cp))
cp++;
if (*cp == '-') {
cp++;
isneg = 1;
}
if (*cp == '+')
cp++;
if (*cp != '.' && !isdigit(*cp))
return 0;
while (*cp != '\0' && (ind = strchr(digits, *cp)) != NULL) {
dec_i = (dec_i << 3) + (dec_i << 1); /* multiply by 10 */
dec_i += (ind - digits);
cp++;
}
if (*cp != '\0' && !isspace(*cp)) {
if (*cp++ != '.')
return 0;
while (ndec < 9 && *cp != '\0'
&& (ind = strchr(digits, *cp)) != NULL) {
ndec++;
dec_f = (dec_f << 3) + (dec_f << 1); /* *10 */
dec_f += (ind - digits);
cp++;
}
while (isdigit(*cp))
cp++;
if (*cp != '\0' && !isspace(*cp))
return 0;
}
if (ndec > 0) {
register u_long tmp;
register u_long bit;
register u_long ten_fact;
ten_fact = ten_to_the_n[ndec];
tmp = 0;
bit = 0x80000000;
while (bit != 0) {
dec_f <<= 1;
if (dec_f >= ten_fact) {
tmp |= bit;
dec_f -= ten_fact;
}
bit >>= 1;
}
if ((dec_f << 1) > ten_fact)
tmp++;
dec_f = tmp;
}
if (isneg)
M_NEG(dec_i, dec_f);
lfp->l_ui = dec_i;
lfp->l_uf = dec_f;
return 1;
}
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