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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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81
Objects/floatobject.c
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@ -177,7 +177,7 @@ still supported but now *officially* useless: if pend is not NULL,
PyObject *
PyFloat_FromString(PyObject *v, char **pend)
{
const char *s, *last, *end, *sp;
const char *s, *last, *end;
double x;
char buffer[256]; /* for errors */
#ifdef Py_USING_UNICODE
@ -212,81 +212,42 @@ PyFloat_FromString(PyObject *v, char **pend)
"float() argument must be a string or a number");
return NULL;
}
last = s + len;
while (*s && isspace(Py_CHARMASK(*s)))
s++;
if (*s == '\0') {
PyErr_SetString(PyExc_ValueError, "empty string for float()");
return NULL;
}
sp = s;
/* We don't care about overflow or underflow. If the platform supports
* them, infinities and signed zeroes (on underflow) are fine.
* However, strtod can return 0 for denormalized numbers, where atof
* does not. So (alas!) we special-case a zero result. Note that
* whether strtod sets errno on underflow is not defined, so we can't
* key off errno.
*/
/* We don't care about overflow or underflow. If the platform
* supports them, infinities and signed zeroes (on underflow) are
* fine. */
errno = 0;
PyFPE_START_PROTECT("strtod", return NULL)
x = PyOS_ascii_strtod(s, (char **)&end);
PyFPE_END_PROTECT(x)
errno = 0;
/* Believe it or not, Solaris 2.6 can move end *beyond* the null
byte at the end of the string, when the input is inf(inity). */
if (end > last)
end = last;
/* Check for inf and nan. This is done late because it rarely happens. */
if (end == s) {
char *p = (char*)sp;
int sign = 1;
if (*p == '-') {
sign = -1;
p++;
if (errno == ENOMEM)
PyErr_NoMemory();
else {
PyOS_snprintf(buffer, sizeof(buffer),
"invalid literal for float(): %.200s", s);
PyErr_SetString(PyExc_ValueError, buffer);
}
if (*p == '+') {
p++;
}
if (PyOS_strnicmp(p, "inf", 4) == 0) {
Py_RETURN_INF(sign);
}
if (PyOS_strnicmp(p, "infinity", 9) == 0) {
Py_RETURN_INF(sign);
}
#ifdef Py_NAN
if(PyOS_strnicmp(p, "nan", 4) == 0) {
Py_RETURN_NAN;
}
#endif
PyOS_snprintf(buffer, sizeof(buffer),
"invalid literal for float(): %.200s", s);
PyErr_SetString(PyExc_ValueError, buffer);
return NULL;
}
/* Since end != s, the platform made *some* kind of sense out
of the input. Trust it. */
while (*end && isspace(Py_CHARMASK(*end)))
end++;
if (*end != '\0') {
PyOS_snprintf(buffer, sizeof(buffer),
"invalid literal for float(): %.200s", s);
PyErr_SetString(PyExc_ValueError, buffer);
if (end != last) {
if (*end == '\0')
PyErr_SetString(PyExc_ValueError,
"null byte in argument for float()");
else {
PyOS_snprintf(buffer, sizeof(buffer),
"invalid literal for float(): %.200s", s);
PyErr_SetString(PyExc_ValueError, buffer);
}
return NULL;
}
else if (end != last) {
PyErr_SetString(PyExc_ValueError,
"null byte in argument for float()");
return NULL;
}
if (x == 0.0) {
/* See above -- may have been strtod being anal
about denorms. */
PyFPE_START_PROTECT("atof", return NULL)
x = PyOS_ascii_atof(s);
PyFPE_END_PROTECT(x)
errno = 0; /* whether atof ever set errno is undefined */
}
return PyFloat_FromDouble(x);
}