view Python/atof.c @ 58352:0895040adeff 2.6

Merged revisions 77517,77525 via svnmerge from svn+ssh://pythondev@svn.python.org/python/trunk ........ r77517 | r.david.murray | 2010-01-16 00:15:17 -0500 (Sat, 16 Jan 2010) | 6 lines Issue #1670765: Prevent email.generator.Generator from re-wrapping headers in multipart/signed MIME parts, which fixes one of the sources of invalid modifications to such parts by Generator. Patch and tests by Martin von Gagern. ........ r77525 | r.david.murray | 2010-01-16 11:08:32 -0500 (Sat, 16 Jan 2010) | 2 lines Fix issue number in comment. ........
author R. David Murray <rdmurray@bitdance.com>
date Sat, 16 Jan 2010 16:32:39 +0000
parents 2dea40e40d9d
children fd25030223b0
line wrap: on
line source


/* Just in case you haven't got an atof() around...
   This one doesn't check for bad syntax or overflow,
   and is slow and inaccurate.
   But it's good enough for the occasional string literal... */

#include "pyconfig.h"

#include <ctype.h>

double atof(char *s)
{
	double a = 0.0;
	int e = 0;
	int c;
	while ((c = *s++) != '\0' && isdigit(c)) {
		a = a*10.0 + (c - '0');
	}
	if (c == '.') {
		while ((c = *s++) != '\0' && isdigit(c)) {
			a = a*10.0 + (c - '0');
			e = e-1;
		}
	}
	if (c == 'e' || c == 'E') {
		int sign = 1;
		int i = 0;
		c = *s++;
		if (c == '+')
			c = *s++;
		else if (c == '-') {
			c = *s++;
			sign = -1;
		}
		while (isdigit(c)) {
			i = i*10 + (c - '0');
			c = *s++;
		}
		e += i*sign;
	}
	while (e > 0) {
		a *= 10.0;
		e--;
	}
	while (e < 0) {
		a *= 0.1;
		e++;
	}
	return a;
}