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#include "compat.h"
#include <ctype.h>
#if ! HAVE_STRTOD
static double pow10(int power)
{
int i;
double result = 1.0, multiplier = 10.0;
if (power < 0) { multiplier = 0.1; power *= -1; }
for (i = 0; i < power; i++) { result *= multiplier; }
return result;
}
double
strtod(const char *nptr, char **endptr)
{
int i = 0, neg = 0;
double result = 0;
if (nptr == 0) return 0.0;
while (isspace(nptr[i])) i++;
if (nptr[i] == '-') neg = 1;
else if (! isdigit(nptr[i]) && nptr[i] != '+') {
/* "If no conversion is performed, zero is returned and the value
* of nptr is stored in the location referenced by endptr." */
if (endptr) *endptr = nptr;
return result;
}
if (nptr[i] == '-' || nptr[i] == '+') i++;
while (isdigit(nptr[i])) {
result *= 10;
result += (nptr[i] - '0');
i++;
}
/* check for decimal places */
if (nptr[i] == ',' || nptr[i] == '.') {
double fractional = 0.0;
int decimal_pt = i;
i++;
while (isdigit(nptr[i])) {
fractional += (nptr[i] - '0') * pow10(decimal_pt - i);
i++;
}
result += fractional;
}
/* check for exponent */
if (nptr[i] == 'e' || nptr[i] == 'E') {
int exponent = 0, expneg = 0;
i++;
if (nptr[i] == '-') { expneg = 1; i++; }
if (nptr[i] == '+') i++;
while (isdigit(nptr[i])) {
exponent *= 10;
exponent += (nptr[i] - '0');
i++;
}
if (expneg) exponent *= -1;
result *= pow10(exponent);
}
if (neg) result *= -1;
if (endptr) *endptr = nptr + i;
return result;
}
#endif
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