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Backport r71967 changes from py3k to trunk.

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(Internal plumbing changes for float parsing.)
This commit is contained in:
Mark Dickinson 2009-04-26 16:04:05 +00:00
parent 944c6aedd0
commit 6d6b220215
2 changed files with 78 additions and 90 deletions
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87
Python/pystrtod.c
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@ -71,6 +71,10 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
decimal_point_pos = NULL;
/* Set errno to zero, so that we can distinguish zero results
and underflows */
errno = 0;
/* We process any leading whitespace and the optional sign manually,
then pass the remainder to the system strtod. This ensures that
the result of an underflow has the correct sign. (bug #1725) */
@ -84,27 +88,53 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
if (*p == '-') {
negate = 1;
p++;
} else if (*p == '+') {
}
else if (*p == '+') {
p++;
}
/* What's left should begin with a digit, a decimal point, or one of
the letters i, I, n, N. It should not begin with 0x or 0X */
if ((!ISDIGIT(*p) &&
*p != '.' && *p != 'i' && *p != 'I' && *p != 'n' && *p != 'N')
||
(*p == '0' && (p[1] == 'x' || p[1] == 'X')))
{
if (endptr)
*endptr = (char*)nptr;
errno = EINVAL;
return val;
/* Parse infinities and nans */
if (*p == 'i' || *p == 'I') {
if (PyOS_strnicmp(p, "inf", 3) == 0) {
val = Py_HUGE_VAL;
if (PyOS_strnicmp(p+3, "inity", 5) == 0)
fail_pos = (char *)p+8;
else
fail_pos = (char *)p+3;
goto got_val;
}
else
goto invalid_string;
}
digits_pos = p;
#ifdef Py_NAN
if (*p == 'n' || *p == 'N') {
if (PyOS_strnicmp(p, "nan", 3) == 0) {
val = Py_NAN;
fail_pos = (char *)p+3;
goto got_val;
}
else
goto invalid_string;
}
#endif
if (decimal_point[0] != '.' ||
/* Some platform strtods accept hex floats; Python shouldn't (at the
moment), so we check explicitly for strings starting with '0x'. */
if (*p == '0' && (*(p+1) == 'x' || *(p+1) == 'X'))
goto invalid_string;
/* Check that what's left begins with a digit or decimal point */
if (!ISDIGIT(*p) && *p != '.')
goto invalid_string;
digits_pos = p;
if (decimal_point[0] != '.' ||
decimal_point[1] != 0)
{
/* Look for a '.' in the input; if present, it'll need to be
swapped for the current locale's decimal point before we
call strtod. On the other hand, if we find the current
locale's decimal point then the input is invalid. */
while (ISDIGIT(*p))
p++;
@ -112,6 +142,7 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
{
decimal_point_pos = p++;
/* locate end of number */
while (ISDIGIT(*p))
p++;
@ -124,27 +155,16 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
end = p;
}
else if (strncmp(p, decimal_point, decimal_point_len) == 0)
{
/* Python bug #1417699 */
if (endptr)
*endptr = (char*)nptr;
errno = EINVAL;
return val;
}
goto invalid_string;
/* For the other cases, we need not convert the decimal
point */
}
/* Set errno to zero, so that we can distinguish zero results
and underflows */
errno = 0;
if (decimal_point_pos)
{
if (decimal_point_pos) {
char *copy, *c;
/* We need to convert the '.' to the locale specific decimal
point */
/* Create a copy of the input, with the '.' converted to the
locale-specific decimal point */
copy = (char *)PyMem_MALLOC(end - digits_pos +
1 + decimal_point_len);
if (copy == NULL) {
@ -185,8 +205,9 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
}
if (fail_pos == digits_pos)
fail_pos = (char *)nptr;
goto invalid_string;
got_val:
if (negate && fail_pos != nptr)
val = -val;
@ -194,6 +215,12 @@ PyOS_ascii_strtod(const char *nptr, char **endptr)
*endptr = fail_pos;
return val;
invalid_string:
if (endptr)
*endptr = (char*)nptr;
errno = EINVAL;
return -1.0;
}
double