jsnuminlines.h
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef jsnuminlines_h___
#define jsnuminlines_h___
#include "vm/NumericConversions.h"
#include "vm/Unicode.h"
#include "jsstrinlines.h"
namespace js {
template<typename T> struct NumberTraits { };
template<> struct NumberTraits<int32_t> {
static JS_ALWAYS_INLINE int32_t NaN() { return 0; }
static JS_ALWAYS_INLINE int32_t toSelfType(int32_t i) { return i; }
static JS_ALWAYS_INLINE int32_t toSelfType(double d) { return ToUint32(d); }
};
template<> struct NumberTraits<double> {
static JS_ALWAYS_INLINE double NaN() { return js_NaN; }
static JS_ALWAYS_INLINE double toSelfType(int32_t i) { return i; }
static JS_ALWAYS_INLINE double toSelfType(double d) { return d; }
};
template<typename T>
static JS_ALWAYS_INLINE bool
StringToNumberType(JSContext *cx, JSString *str, T *result)
{
size_t length = str->length();
const jschar *chars = str->getChars(NULL);
if (!chars)
return false;
if (length == 1) {
jschar c = chars[0];
if ('0' <= c && c <= '9') {
*result = NumberTraits<T>::toSelfType(T(c - '0'));
return true;
}
if (unicode::IsSpace(c)) {
*result = NumberTraits<T>::toSelfType(T(0));
return true;
}
*result = NumberTraits<T>::NaN();
return true;
}
const jschar *end = chars + length;
const jschar *bp = SkipSpace(chars, end);
/* ECMA doesn't allow signed hex numbers (bug 273467). */
if (end - bp >= 2 && bp[0] == '0' && (bp[1] == 'x' || bp[1] == 'X')) {
/* Looks like a hex number. */
const jschar *endptr;
double d;
if (!GetPrefixInteger(cx, bp + 2, end, 16, &endptr, &d) || SkipSpace(endptr, end) != end) {
*result = NumberTraits<T>::NaN();
return true;
}
*result = NumberTraits<T>::toSelfType(d);
return true;
}
/*
* Note that ECMA doesn't treat a string beginning with a '0' as
* an octal number here. This works because all such numbers will
* be interpreted as decimal by js_strtod. Also, any hex numbers
* that have made it here (which can only be negative ones) will
* be treated as 0 without consuming the 'x' by js_strtod.
*/
const jschar *ep;
double d;
if (!js_strtod(cx, bp, end, &ep, &d) || SkipSpace(ep, end) != end) {
*result = NumberTraits<T>::NaN();
return true;
}
*result = NumberTraits<T>::toSelfType(d);
return true;
}
} // namespace js
#endif /* jsnuminlines_h___ */