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cobalt / cobalt / 71840339e1109efe930df5c60712d91cdcc962a8 / . / src / third_party / mozjs-45 / js / src / jsnum.cpp
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* 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/. */
/*
* JS number type and wrapper class.
*/
#include "jsnum.h"
#include "mozilla/double-conversion.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/PodOperations.h"
#include "mozilla/RangedPtr.h"
#ifdef HAVE_LOCALECONV
#include <locale.h>
#endif
#include <math.h>
#include <string.h>
#include "jsatom.h"
#include "jscntxt.h"
#include "jsdtoa.h"
#include "jsobj.h"
#include "jsstr.h"
#include "jstypes.h"
#include "js/Conversions.h"
#include "vm/GlobalObject.h"
#include "vm/StringBuffer.h"
#include "jsatominlines.h"
#include "vm/NativeObject-inl.h"
#include "vm/NumberObject-inl.h"
#include "vm/String-inl.h"
using namespace js;
using mozilla::Abs;
using mozilla::ArrayLength;
using mozilla::MinNumberValue;
using mozilla::NegativeInfinity;
using mozilla::PodCopy;
using mozilla::PositiveInfinity;
using mozilla::RangedPtr;
using JS::AutoCheckCannotGC;
using JS::GenericNaN;
using JS::ToInt8;
using JS::ToInt16;
using JS::ToInt32;
using JS::ToInt64;
using JS::ToUint32;
using JS::ToUint64;
/*
* If we're accumulating a decimal number and the number is >= 2^53, then the
* fast result from the loop in Get{Prefix,Decimal}Integer may be inaccurate.
* Call js_strtod_harder to get the correct answer.
*/
template <typename CharT>
static bool
ComputeAccurateDecimalInteger(ExclusiveContext* cx, const CharT* start, const CharT* end,
double* dp)
{
size_t length = end - start;
ScopedJSFreePtr<char> cstr(cx->pod_malloc<char>(length + 1));
if (!cstr)
return false;
for (size_t i = 0; i < length; i++) {
char c = char(start[i]);
MOZ_ASSERT(('0' <= c && c <= '9') || ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z'));
cstr[i] = c;
}
cstr[length] = 0;
char* estr;
int err = 0;
*dp = js_strtod_harder(cx->dtoaState(), cstr, &estr, &err);
if (err == JS_DTOA_ENOMEM) {
ReportOutOfMemory(cx);
return false;
}
return true;
}
namespace {
template <typename CharT>
class BinaryDigitReader
{
const int base; /* Base of number; must be a power of 2 */
int digit; /* Current digit value in radix given by base */
int digitMask; /* Mask to extract the next bit from digit */
const CharT* start; /* Pointer to the remaining digits */
const CharT* end; /* Pointer to first non-digit */
public:
BinaryDigitReader(int base, const CharT* start, const CharT* end)
: base(base), digit(0), digitMask(0), start(start), end(end)
{
}
/* Return the next binary digit from the number, or -1 if done. */
int nextDigit() {
if (digitMask == 0) {
if (start == end)
return -1;
int c = *start++;
MOZ_ASSERT(('0' <= c && c <= '9') || ('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z'));
if ('0' <= c && c <= '9')
digit = c - '0';
else if ('a' <= c && c <= 'z')
digit = c - 'a' + 10;
else
digit = c - 'A' + 10;
digitMask = base >> 1;
}
int bit = (digit & digitMask) != 0;
digitMask >>= 1;
return bit;
}
};
} /* anonymous namespace */
/*
* The fast result might also have been inaccurate for power-of-two bases. This
* happens if the addition in value * 2 + digit causes a round-down to an even
* least significant mantissa bit when the first dropped bit is a one. If any
* of the following digits in the number (which haven't been added in yet) are
* nonzero, then the correct action would have been to round up instead of
* down. An example occurs when reading the number 0x1000000000000081, which
* rounds to 0x1000000000000000 instead of 0x1000000000000100.
*/
template <typename CharT>
static double
ComputeAccurateBinaryBaseInteger(const CharT* start, const CharT* end, int base)
{
BinaryDigitReader<CharT> bdr(base, start, end);
/* Skip leading zeroes. */
int bit;
do {
bit = bdr.nextDigit();
} while (bit == 0);
MOZ_ASSERT(bit == 1); // guaranteed by Get{Prefix,Decimal}Integer
/* Gather the 53 significant bits (including the leading 1). */
double value = 1.0;
for (int j = 52; j > 0; j--) {
bit = bdr.nextDigit();
if (bit < 0)
return value;
value = value * 2 + bit;
}
/* bit2 is the 54th bit (the first dropped from the mantissa). */
int bit2 = bdr.nextDigit();
if (bit2 >= 0) {
double factor = 2.0;
int sticky = 0; /* sticky is 1 if any bit beyond the 54th is 1 */
int bit3;
while ((bit3 = bdr.nextDigit()) >= 0) {
sticky |= bit3;
factor *= 2;
}
value += bit2 & (bit | sticky);
value *= factor;
}
return value;
}
template <typename CharT>
double
js::ParseDecimalNumber(const mozilla::Range<const CharT> chars)
{
MOZ_ASSERT(chars.length() > 0);
uint64_t dec = 0;
RangedPtr<const CharT> s = chars.start(), end = chars.end();
do {
CharT c = *s;
MOZ_ASSERT('0' <= c && c <= '9');
uint8_t digit = c - '0';
uint64_t next = dec * 10 + digit;
MOZ_ASSERT(next < DOUBLE_INTEGRAL_PRECISION_LIMIT,
"next value won't be an integrally-precise double");
dec = next;
} while (++s < end);
return static_cast<double>(dec);
}
template double
js::ParseDecimalNumber(const mozilla::Range<const Latin1Char> chars);
template double
js::ParseDecimalNumber(const mozilla::Range<const char16_t> chars);
template <typename CharT>
bool
js::GetPrefixInteger(ExclusiveContext* cx, const CharT* start, const CharT* end, int base,
const CharT** endp, double* dp)
{
MOZ_ASSERT(start <= end);
MOZ_ASSERT(2 <= base && base <= 36);
const CharT* s = start;
double d = 0.0;
for (; s < end; s++) {
int digit;
CharT c = *s;
if ('0' <= c && c <= '9')
digit = c - '0';
else if ('a' <= c && c <= 'z')
digit = c - 'a' + 10;
else if ('A' <= c && c <= 'Z')
digit = c - 'A' + 10;
else
break;
if (digit >= base)
break;
d = d * base + digit;
}
*endp = s;
*dp = d;
/* If we haven't reached the limit of integer precision, we're done. */
if (d < DOUBLE_INTEGRAL_PRECISION_LIMIT)
return true;
/*
* Otherwise compute the correct integer from the prefix of valid digits
* if we're computing for base ten or a power of two. Don't worry about
* other bases; see 15.1.2.2 step 13.
*/
if (base == 10)
return ComputeAccurateDecimalInteger(cx, start, s, dp);
if ((base & (base - 1)) == 0)
*dp = ComputeAccurateBinaryBaseInteger(start, s, base);
return true;
}
template bool
js::GetPrefixInteger(ExclusiveContext* cx, const char16_t* start, const char16_t* end, int base,
const char16_t** endp, double* dp);
template bool
js::GetPrefixInteger(ExclusiveContext* cx, const Latin1Char* start, const Latin1Char* end,
int base, const Latin1Char** endp, double* dp);
bool
js::GetDecimalInteger(ExclusiveContext* cx, const char16_t* start, const char16_t* end, double* dp)
{
MOZ_ASSERT(start <= end);
const char16_t* s = start;
double d = 0.0;
for (; s < end; s++) {
char16_t c = *s;
MOZ_ASSERT('0' <= c && c <= '9');
int digit = c - '0';
d = d * 10 + digit;
}
*dp = d;
// If we haven't reached the limit of integer precision, we're done.
if (d < DOUBLE_INTEGRAL_PRECISION_LIMIT)
return true;
// Otherwise compute the correct integer from the prefix of valid digits.
return ComputeAccurateDecimalInteger(cx, start, s, dp);
}
static bool
num_parseFloat(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
if (args.length() == 0) {
args.rval().setNaN();
return true;
}
JSString* str = ToString<CanGC>(cx, args[0]);
if (!str)
return false;
JSLinearString* linear = str->ensureLinear(cx);
if (!linear)
return false;
double d;
AutoCheckCannotGC nogc;
if (linear->hasLatin1Chars()) {
const Latin1Char* begin = linear->latin1Chars(nogc);
const Latin1Char* end;
if (!js_strtod(cx, begin, begin + linear->length(), &end, &d))
return false;
if (end == begin)
d = GenericNaN();
} else {
const char16_t* begin = linear->twoByteChars(nogc);
const char16_t* end;
if (!js_strtod(cx, begin, begin + linear->length(), &end, &d))
return false;
if (end == begin)
d = GenericNaN();
}
args.rval().setDouble(d);
return true;
}
template <typename CharT>
static bool
ParseIntImpl(JSContext* cx, const CharT* chars, size_t length, bool stripPrefix, int32_t radix,
double* res)
{
/* Step 2. */
const CharT* end = chars + length;
const CharT* s = SkipSpace(chars, end);
MOZ_ASSERT(chars <= s);
MOZ_ASSERT(s <= end);
/* Steps 3-4. */
bool negative = (s != end && s[0] == '-');
/* Step 5. */
if (s != end && (s[0] == '-' || s[0] == '+'))
s++;
/* Step 10. */
if (stripPrefix) {
if (end - s >= 2 && s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) {
s += 2;
radix = 16;
}
}
/* Steps 11-15. */
const CharT* actualEnd;
double d;
if (!GetPrefixInteger(cx, s, end, radix, &actualEnd, &d))
return false;
if (s == actualEnd)
*res = GenericNaN();
else
*res = negative ? -d : d;
return true;
}
/* ES5 15.1.2.2. */
bool
js::num_parseInt(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
/* Fast paths and exceptional cases. */
if (args.length() == 0) {
args.rval().setNaN();
return true;
}
if (args.length() == 1 ||
(args[1].isInt32() && (args[1].toInt32() == 0 || args[1].toInt32() == 10))) {
if (args[0].isInt32()) {
args.rval().set(args[0]);
return true;
}
/*
* Step 1 is |inputString = ToString(string)|. When string >=
* 1e21, ToString(string) is in the form "NeM". 'e' marks the end of
* the word, which would mean the result of parseInt(string) should be |N|.
*
* To preserve this behaviour, we can't use the fast-path when string >
* 1e21, or else the result would be |NeM|.
*
* The same goes for values smaller than 1.0e-6, because the string would be in
* the form of "Ne-M".
*/
if (args[0].isDouble()) {
double d = args[0].toDouble();
if (1.0e-6 < d && d < 1.0e21) {
args.rval().setNumber(floor(d));
return true;
}
if (-1.0e21 < d && d < -1.0e-6) {
args.rval().setNumber(-floor(-d));
return true;
}
if (d == 0.0) {
args.rval().setInt32(0);
return true;
}
}
}
/* Step 1. */
RootedString inputString(cx, ToString<CanGC>(cx, args[0]));
if (!inputString)
return false;
args[0].setString(inputString);
/* Steps 6-9. */
bool stripPrefix = true;
int32_t radix;
if (!args.hasDefined(1)) {
radix = 10;
} else {
if (!ToInt32(cx, args[1], &radix))
return false;
if (radix == 0) {
radix = 10;
} else {
if (radix < 2 || radix > 36) {
args.rval().setNaN();
return true;
}
if (radix != 16)
stripPrefix = false;
}
}
JSLinearString* linear = inputString->ensureLinear(cx);
if (!linear)
return false;
AutoCheckCannotGC nogc;
size_t length = inputString->length();
double number;
if (linear->hasLatin1Chars()) {
if (!ParseIntImpl(cx, linear->latin1Chars(nogc), length, stripPrefix, radix, &number))
return false;
} else {
if (!ParseIntImpl(cx, linear->twoByteChars(nogc), length, stripPrefix, radix, &number))
return false;
}
args.rval().setNumber(number);
return true;
}
static const JSFunctionSpec number_functions[] = {
JS_SELF_HOSTED_FN(js_isNaN_str, "Global_isNaN", 1, JSPROP_RESOLVING),
JS_SELF_HOSTED_FN(js_isFinite_str, "Global_isFinite", 1, JSPROP_RESOLVING),
JS_FS_END
};
const Class NumberObject::class_ = {
js_Number_str,
JSCLASS_HAS_RESERVED_SLOTS(1) | JSCLASS_HAS_CACHED_PROTO(JSProto_Number)
};
static bool
Number(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
/* Sample JS_CALLEE before clobbering. */
bool isConstructing = args.isConstructing();
if (args.length() > 0) {
if (!ToNumber(cx, args[0]))
return false;
args.rval().set(args[0]);
} else {
args.rval().setInt32(0);
}
if (!isConstructing)
return true;
RootedObject newTarget(cx, &args.newTarget().toObject());
RootedObject proto(cx);
if (!GetPrototypeFromConstructor(cx, newTarget, &proto))
return false;
JSObject* obj = NumberObject::create(cx, args.rval().toNumber(), proto);
if (!obj)
return false;
args.rval().setObject(*obj);
return true;
}
MOZ_ALWAYS_INLINE bool
IsNumber(HandleValue v)
{
return v.isNumber() || (v.isObject() && v.toObject().is<NumberObject>());
}
static inline double
Extract(const Value& v)
{
if (v.isNumber())
return v.toNumber();
return v.toObject().as<NumberObject>().unbox();
}
#if JS_HAS_TOSOURCE
MOZ_ALWAYS_INLINE bool
num_toSource_impl(JSContext* cx, const CallArgs& args)
{
double d = Extract(args.thisv());
StringBuffer sb(cx);
if (!sb.append("(new Number(") ||
!NumberValueToStringBuffer(cx, NumberValue(d), sb) ||
!sb.append("))"))
{
return false;
}
JSString* str = sb.finishString();
if (!str)
return false;
args.rval().setString(str);
return true;
}
static bool
num_toSource(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toSource_impl>(cx, args);
}
#endif
ToCStringBuf::ToCStringBuf() : dbuf(nullptr)
{
static_assert(sbufSize >= DTOSTR_STANDARD_BUFFER_SIZE,
"builtin space must be large enough to store even the "
"longest string produced by a conversion");
}
ToCStringBuf::~ToCStringBuf()
{
js_free(dbuf);
}
MOZ_ALWAYS_INLINE
static JSFlatString*
LookupDtoaCache(ExclusiveContext* cx, double d)
{
if (JSCompartment* comp = cx->compartment()) {
if (JSFlatString* str = comp->dtoaCache.lookup(10, d))
return str;
}
return nullptr;
}
MOZ_ALWAYS_INLINE
static void
CacheNumber(ExclusiveContext* cx, double d, JSFlatString* str)
{
if (JSCompartment* comp = cx->compartment())
comp->dtoaCache.cache(10, d, str);
}
MOZ_ALWAYS_INLINE
static JSFlatString*
LookupInt32ToString(ExclusiveContext* cx, int32_t si)
{
if (si >= 0 && StaticStrings::hasInt(si))
return cx->staticStrings().getInt(si);
return LookupDtoaCache(cx, si);
}
template <typename T>
MOZ_ALWAYS_INLINE
static T*
BackfillInt32InBuffer(int32_t si, T* buffer, size_t size, size_t* length)
{
uint32_t ui = Abs(si);
MOZ_ASSERT_IF(si == INT32_MIN, ui == uint32_t(INT32_MAX) + 1);
RangedPtr<T> end(buffer + size - 1, buffer, size);
*end = '\0';
RangedPtr<T> start = BackfillIndexInCharBuffer(ui, end);
if (si < 0)
*--start = '-';
*length = end - start;
return start.get();
}
template <AllowGC allowGC>
JSFlatString*
js::Int32ToString(ExclusiveContext* cx, int32_t si)
{
if (JSFlatString* str = LookupInt32ToString(cx, si))
return str;
Latin1Char buffer[JSFatInlineString::MAX_LENGTH_LATIN1 + 1];
size_t length;
Latin1Char* start = BackfillInt32InBuffer(si, buffer, ArrayLength(buffer), &length);
mozilla::Range<const Latin1Char> chars(start, length);
JSInlineString* str = NewInlineString<allowGC>(cx, chars);
if (!str)
return nullptr;
CacheNumber(cx, si, str);
return str;
}
template JSFlatString*
js::Int32ToString<CanGC>(ExclusiveContext* cx, int32_t si);
template JSFlatString*
js::Int32ToString<NoGC>(ExclusiveContext* cx, int32_t si);
JSAtom*
js::Int32ToAtom(ExclusiveContext* cx, int32_t si)
{
if (JSFlatString* str = LookupInt32ToString(cx, si))
return js::AtomizeString(cx, str);
char buffer[JSFatInlineString::MAX_LENGTH_TWO_BYTE + 1];
size_t length;
char* start = BackfillInt32InBuffer(si, buffer, JSFatInlineString::MAX_LENGTH_TWO_BYTE + 1, &length);
JSAtom* atom = Atomize(cx, start, length);
if (!atom)
return nullptr;
CacheNumber(cx, si, atom);
return atom;
}
/* Returns a non-nullptr pointer to inside cbuf. */
static char*
Int32ToCString(ToCStringBuf* cbuf, int32_t i, size_t* len, int base = 10)
{
uint32_t u = Abs(i);
RangedPtr<char> cp(cbuf->sbuf + ToCStringBuf::sbufSize - 1, cbuf->sbuf, ToCStringBuf::sbufSize);
char* end = cp.get();
*cp = '\0';
/* Build the string from behind. */
switch (base) {
case 10:
cp = BackfillIndexInCharBuffer(u, cp);
break;
case 16:
do {
unsigned newu = u / 16;
*--cp = "0123456789abcdef"[u - newu * 16];
u = newu;
} while (u != 0);
break;
default:
MOZ_ASSERT(base >= 2 && base <= 36);
do {
unsigned newu = u / base;
*--cp = "0123456789abcdefghijklmnopqrstuvwxyz"[u - newu * base];
u = newu;
} while (u != 0);
break;
}
if (i < 0)
*--cp = '-';
*len = end - cp.get();
return cp.get();
}
template <AllowGC allowGC>
static JSString*
NumberToStringWithBase(ExclusiveContext* cx, double d, int base);
MOZ_ALWAYS_INLINE bool
num_toString_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
double d = Extract(args.thisv());
int32_t base = 10;
if (args.hasDefined(0)) {
double d2;
if (!ToInteger(cx, args[0], &d2))
return false;
if (d2 < 2 || d2 > 36) {
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_BAD_RADIX);
return false;
}
base = int32_t(d2);
}
JSString* str = NumberToStringWithBase<CanGC>(cx, d, base);
if (!str) {
JS_ReportOutOfMemory(cx);
return false;
}
args.rval().setString(str);
return true;
}
bool
js::num_toString(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toString_impl>(cx, args);
}
#if !EXPOSE_INTL_API
MOZ_ALWAYS_INLINE bool
num_toLocaleString_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
double d = Extract(args.thisv());
RootedString str(cx, NumberToStringWithBase<CanGC>(cx, d, 10));
if (!str) {
JS_ReportOutOfMemory(cx);
return false;
}
/*
* Create the string, move back to bytes to make string twiddling
* a bit easier and so we can insert platform charset seperators.
*/
JSAutoByteString numBytes(cx, str);
if (!numBytes)
return false;
const char* num = numBytes.ptr();
if (!num)
return false;
/*
* Find the first non-integer value, whether it be a letter as in
* 'Infinity', a decimal point, or an 'e' from exponential notation.
*/
const char* nint = num;
if (*nint == '-')
nint++;
while (*nint >= '0' && *nint <= '9')
nint++;
int digits = nint - num;
const char* end = num + digits;
if (!digits) {
args.rval().setString(str);
return true;
}
JSRuntime* rt = cx->runtime();
size_t thousandsLength = strlen(rt->thousandsSeparator);
size_t decimalLength = strlen(rt->decimalSeparator);
/* Figure out how long resulting string will be. */
int buflen = strlen(num);
if (*nint == '.')
buflen += decimalLength - 1; /* -1 to account for existing '.' */
const char* numGrouping;
const char* tmpGroup;
numGrouping = tmpGroup = rt->numGrouping;
int remainder = digits;
if (*num == '-')
remainder--;
while (*tmpGroup != CHAR_MAX && *tmpGroup != '\0') {
if (*tmpGroup >= remainder)
break;
buflen += thousandsLength;
remainder -= *tmpGroup;
tmpGroup++;
}
int nrepeat;
if (*tmpGroup == '\0' && *numGrouping != '\0') {
nrepeat = (remainder - 1) / tmpGroup[-1];
buflen += thousandsLength * nrepeat;
remainder -= nrepeat * tmpGroup[-1];
} else {
nrepeat = 0;
}
tmpGroup--;
char* buf = cx->pod_malloc<char>(buflen + 1);
if (!buf)
return false;
char* tmpDest = buf;
const char* tmpSrc = num;
while (*tmpSrc == '-' || remainder--) {
MOZ_ASSERT(tmpDest - buf < buflen);
*tmpDest++ = *tmpSrc++;
}
while (tmpSrc < end) {
MOZ_ASSERT(tmpDest - buf + ptrdiff_t(thousandsLength) <= buflen);
strcpy(tmpDest, rt->thousandsSeparator);
tmpDest += thousandsLength;
MOZ_ASSERT(tmpDest - buf + *tmpGroup <= buflen);
js_memcpy(tmpDest, tmpSrc, *tmpGroup);
tmpDest += *tmpGroup;
tmpSrc += *tmpGroup;
if (--nrepeat < 0)
tmpGroup--;
}
if (*nint == '.') {
MOZ_ASSERT(tmpDest - buf + ptrdiff_t(decimalLength) <= buflen);
strcpy(tmpDest, rt->decimalSeparator);
tmpDest += decimalLength;
MOZ_ASSERT(tmpDest - buf + ptrdiff_t(strlen(nint + 1)) <= buflen);
strcpy(tmpDest, nint + 1);
} else {
MOZ_ASSERT(tmpDest - buf + ptrdiff_t(strlen(nint)) <= buflen);
strcpy(tmpDest, nint);
}
if (cx->runtime()->localeCallbacks && cx->runtime()->localeCallbacks->localeToUnicode) {
Rooted<Value> v(cx, StringValue(str));
bool ok = !!cx->runtime()->localeCallbacks->localeToUnicode(cx, buf, &v);
if (ok)
args.rval().set(v);
js_free(buf);
return ok;
}
str = NewStringCopyN<CanGC>(cx, buf, buflen);
js_free(buf);
if (!str)
return false;
args.rval().setString(str);
return true;
}
static bool
num_toLocaleString(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toLocaleString_impl>(cx, args);
}
#endif /* !EXPOSE_INTL_API */
MOZ_ALWAYS_INLINE bool
num_valueOf_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
args.rval().setNumber(Extract(args.thisv()));
return true;
}
bool
js::num_valueOf(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_valueOf_impl>(cx, args);
}
static const unsigned MAX_PRECISION = 100;
static bool
ComputePrecisionInRange(JSContext* cx, int minPrecision, int maxPrecision, HandleValue v,
int* precision)
{
double prec;
if (!ToInteger(cx, v, &prec))
return false;
if (minPrecision <= prec && prec <= maxPrecision) {
*precision = int(prec);
return true;
}
ToCStringBuf cbuf;
if (char* numStr = NumberToCString(cx, &cbuf, prec, 10))
JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_PRECISION_RANGE, numStr);
return false;
}
static bool
DToStrResult(JSContext* cx, double d, JSDToStrMode mode, int precision, const CallArgs& args)
{
char buf[DTOSTR_VARIABLE_BUFFER_SIZE(MAX_PRECISION + 1)];
char* numStr = js_dtostr(cx->mainThread().dtoaState, buf, sizeof buf, mode, precision, d);
if (!numStr) {
JS_ReportOutOfMemory(cx);
return false;
}
JSString* str = NewStringCopyZ<CanGC>(cx, numStr);
if (!str)
return false;
args.rval().setString(str);
return true;
}
/*
* In the following three implementations, we allow a larger range of precision
* than ECMA requires; this is permitted by ECMA-262.
*/
MOZ_ALWAYS_INLINE bool
num_toFixed_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
int precision;
if (args.length() == 0) {
precision = 0;
} else {
if (!ComputePrecisionInRange(cx, -20, MAX_PRECISION, args[0], &precision))
return false;
}
return DToStrResult(cx, Extract(args.thisv()), DTOSTR_FIXED, precision, args);
}
static bool
num_toFixed(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toFixed_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool
num_toExponential_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
JSDToStrMode mode;
int precision;
if (!args.hasDefined(0)) {
mode = DTOSTR_STANDARD_EXPONENTIAL;
precision = 0;
} else {
mode = DTOSTR_EXPONENTIAL;
if (!ComputePrecisionInRange(cx, 0, MAX_PRECISION, args[0], &precision))
return false;
}
return DToStrResult(cx, Extract(args.thisv()), mode, precision + 1, args);
}
static bool
num_toExponential(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toExponential_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool
num_toPrecision_impl(JSContext* cx, const CallArgs& args)
{
MOZ_ASSERT(IsNumber(args.thisv()));
double d = Extract(args.thisv());
if (!args.hasDefined(0)) {
JSString* str = NumberToStringWithBase<CanGC>(cx, d, 10);
if (!str) {
JS_ReportOutOfMemory(cx);
return false;
}
args.rval().setString(str);
return true;
}
int precision;
if (!ComputePrecisionInRange(cx, 1, MAX_PRECISION, args[0], &precision))
return false;
return DToStrResult(cx, d, DTOSTR_PRECISION, precision, args);
}
static bool
num_toPrecision(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsNumber, num_toPrecision_impl>(cx, args);
}
static const JSFunctionSpec number_methods[] = {
#if JS_HAS_TOSOURCE
JS_FN(js_toSource_str, num_toSource, 0, 0),
#endif
JS_FN(js_toString_str, num_toString, 1, 0),
#if EXPOSE_INTL_API
JS_SELF_HOSTED_FN(js_toLocaleString_str, "Number_toLocaleString", 0,0),
#else
JS_FN(js_toLocaleString_str, num_toLocaleString, 0,0),
#endif
JS_FN(js_valueOf_str, num_valueOf, 0, 0),
JS_FN("toFixed", num_toFixed, 1, 0),
JS_FN("toExponential", num_toExponential, 1, 0),
JS_FN("toPrecision", num_toPrecision, 1, 0),
JS_FS_END
};
// ES6 draft ES6 15.7.3.12
static bool
Number_isInteger(JSContext* cx, unsigned argc, Value* vp)
{
CallArgs args = CallArgsFromVp(argc, vp);
if (args.length() < 1 || !args[0].isNumber()) {
args.rval().setBoolean(false);
return true;
}
Value val = args[0];
args.rval().setBoolean(val.isInt32() ||
(mozilla::IsFinite(val.toDouble()) &&
JS::ToInteger(val.toDouble()) == val.toDouble()));
return true;
}
static const JSFunctionSpec number_static_methods[] = {
JS_SELF_HOSTED_FN("isFinite", "Number_isFinite", 1,0),
JS_FN("isInteger", Number_isInteger, 1, 0),
JS_SELF_HOSTED_FN("isNaN", "Number_isNaN", 1,0),
JS_SELF_HOSTED_FN("isSafeInteger", "Number_isSafeInteger", 1,0),
JS_FS_END
};
/*
* Set the exception mask to mask all exceptions and set the FPU precision
* to 53 bit mantissa (64 bit doubles).
*/
void
js::FIX_FPU()
{
#if (defined __GNUC__ && defined __i386__) || \
(defined __SUNPRO_CC && defined __i386)
short control;
asm("fstcw %0" : "=m" (control) : );
control &= ~0x300; // Lower bits 8 and 9 (precision control).
control |= 0x2f3; // Raise bits 0-5 (exception masks) and 9 (64-bit precision).
asm("fldcw %0" : : "m" (control) );
#endif
}
bool
js::InitRuntimeNumberState(JSRuntime* rt)
{
FIX_FPU();
// XXX If EXPOSE_INTL_API becomes true all the time at some point,
// js::InitRuntimeNumberState is no longer fallible, and we should
// change its return type.
#if !EXPOSE_INTL_API
/* Copy locale-specific separators into the runtime strings. */
const char* thousandsSeparator;
const char* decimalPoint;
const char* grouping;
#ifdef HAVE_LOCALECONV
struct lconv* locale = localeconv();
thousandsSeparator = locale->thousands_sep;
decimalPoint = locale->decimal_point;
grouping = locale->grouping;
#else
thousandsSeparator = getenv("LOCALE_THOUSANDS_SEP");
decimalPoint = getenv("LOCALE_DECIMAL_POINT");
grouping = getenv("LOCALE_GROUPING");
#endif
if (!thousandsSeparator)
thousandsSeparator = "'";
if (!decimalPoint)
decimalPoint = ".";
if (!grouping)
grouping = "\3\0";
/*
* We use single malloc to get the memory for all separator and grouping
* strings.
*/
size_t thousandsSeparatorSize = strlen(thousandsSeparator) + 1;
size_t decimalPointSize = strlen(decimalPoint) + 1;
size_t groupingSize = strlen(grouping) + 1;
char* storage = js_pod_malloc<char>(thousandsSeparatorSize +
decimalPointSize +
groupingSize);
if (!storage)
return false;
js_memcpy(storage, thousandsSeparator, thousandsSeparatorSize);
rt->thousandsSeparator = storage;
storage += thousandsSeparatorSize;
js_memcpy(storage, decimalPoint, decimalPointSize);
rt->decimalSeparator = storage;
storage += decimalPointSize;
js_memcpy(storage, grouping, groupingSize);
rt->numGrouping = grouping;
#endif /* !EXPOSE_INTL_API */
return true;
}
#if !EXPOSE_INTL_API
void
js::FinishRuntimeNumberState(JSRuntime* rt)
{
/*
* The free also releases the memory for decimalSeparator and numGrouping
* strings.
*/
char* storage = const_cast<char*>(rt->thousandsSeparator);
js_free(storage);
}
#endif
JSObject*
js::InitNumberClass(JSContext* cx, HandleObject obj)
{
MOZ_ASSERT(obj->isNative());
/* XXX must do at least once per new thread, so do it per JSContext... */
FIX_FPU();
Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>());
RootedObject numberProto(cx, global->createBlankPrototype(cx, &NumberObject::class_));
if (!numberProto)
return nullptr;
numberProto->as<NumberObject>().setPrimitiveValue(0);
RootedFunction ctor(cx);
ctor = global->createConstructor(cx, Number, cx->names().Number, 1);
if (!ctor)
return nullptr;
if (!LinkConstructorAndPrototype(cx, ctor, numberProto))
return nullptr;
/*
* Our NaN must be one particular canonical value, because we rely on NaN
* encoding for our value representation. See Value.h.
*/
static JSConstDoubleSpec number_constants[] = {
{"NaN", GenericNaN() },
{"POSITIVE_INFINITY", mozilla::PositiveInfinity<double>() },
{"NEGATIVE_INFINITY", mozilla::NegativeInfinity<double>() },
{"MAX_VALUE", 1.7976931348623157E+308 },
{"MIN_VALUE", MinNumberValue<double>() },
/* ES6 (April 2014 draft) 20.1.2.6 */
{"MAX_SAFE_INTEGER", 9007199254740991 },
/* ES6 (April 2014 draft) 20.1.2.10 */
{"MIN_SAFE_INTEGER", -9007199254740991, },
/* ES6 (May 2013 draft) 15.7.3.7 */
{"EPSILON", 2.2204460492503130808472633361816e-16},
{0,0}
};
/* Add numeric constants (MAX_VALUE, NaN, &c.) to the Number constructor. */
if (!JS_DefineConstDoubles(cx, ctor, number_constants))
return nullptr;
if (!DefinePropertiesAndFunctions(cx, ctor, nullptr, number_static_methods))
return nullptr;
if (!DefinePropertiesAndFunctions(cx, numberProto, nullptr, number_methods))
return nullptr;
if (!JS_DefineFunctions(cx, global, number_functions))
return nullptr;
/* Number.parseInt should be the same function object as global parseInt. */
RootedId parseIntId(cx, NameToId(cx->names().parseInt));
JSFunction* parseInt = DefineFunction(cx, global, parseIntId, num_parseInt, 2,
JSPROP_RESOLVING);
if (!parseInt)
return nullptr;
RootedValue parseIntValue(cx, ObjectValue(*parseInt));
if (!DefineProperty(cx, ctor, parseIntId, parseIntValue, nullptr, nullptr, 0))
return nullptr;
/* Number.parseFloat should be the same function object as global parseFloat. */
RootedId parseFloatId(cx, NameToId(cx->names().parseFloat));
JSFunction* parseFloat = DefineFunction(cx, global, parseFloatId, num_parseFloat, 1,
JSPROP_RESOLVING);
if (!parseFloat)
return nullptr;
RootedValue parseFloatValue(cx, ObjectValue(*parseFloat));
if (!DefineProperty(cx, ctor, parseFloatId, parseFloatValue, nullptr, nullptr, 0))
return nullptr;
RootedValue valueNaN(cx, cx->runtime()->NaNValue);
RootedValue valueInfinity(cx, cx->runtime()->positiveInfinityValue);
/* ES5 15.1.1.1, 15.1.1.2 */
if (!NativeDefineProperty(cx, global, cx->names().NaN, valueNaN, nullptr, nullptr,
JSPROP_PERMANENT | JSPROP_READONLY | JSPROP_RESOLVING) ||
!NativeDefineProperty(cx, global, cx->names().Infinity, valueInfinity, nullptr, nullptr,
JSPROP_PERMANENT | JSPROP_READONLY | JSPROP_RESOLVING))
{
return nullptr;
}
if (!GlobalObject::initBuiltinConstructor(cx, global, JSProto_Number, ctor, numberProto))
return nullptr;
return numberProto;
}
static char*
FracNumberToCString(ExclusiveContext* cx, ToCStringBuf* cbuf, double d, int base = 10)
{
#ifdef DEBUG
{
int32_t _;
MOZ_ASSERT(!mozilla::NumberIsInt32(d, &_));
}
#endif
char* numStr;
if (base == 10) {
/*
* This is V8's implementation of the algorithm described in the
* following paper:
*
* Printing floating-point numbers quickly and accurately with integers.
* Florian Loitsch, PLDI 2010.
*/
const double_conversion::DoubleToStringConverter& converter
= double_conversion::DoubleToStringConverter::EcmaScriptConverter();
double_conversion::StringBuilder builder(cbuf->sbuf, cbuf->sbufSize);
converter.ToShortest(d, &builder);
numStr = builder.Finalize();
} else {
numStr = cbuf->dbuf = js_dtobasestr(cx->dtoaState(), base, d);
}
return numStr;
}
char*
js::NumberToCString(JSContext* cx, ToCStringBuf* cbuf, double d, int base/* = 10*/)
{
int32_t i;
size_t len;
return mozilla::NumberIsInt32(d, &i)
? Int32ToCString(cbuf, i, &len, base)
: FracNumberToCString(cx, cbuf, d, base);
}
template <AllowGC allowGC>
static JSString*
NumberToStringWithBase(ExclusiveContext* cx, double d, int base)
{
ToCStringBuf cbuf;
char* numStr;
/*
* Caller is responsible for error reporting. When called from trace,
* returning nullptr here will cause us to fall of trace and then retry
* from the interpreter (which will report the error).
*/
if (base < 2 || base > 36)
return nullptr;
JSCompartment* comp = cx->compartment();
int32_t i;
if (mozilla::NumberIsInt32(d, &i)) {
if (base == 10 && StaticStrings::hasInt(i))
return cx->staticStrings().getInt(i);
if (unsigned(i) < unsigned(base)) {
if (i < 10)
return cx->staticStrings().getInt(i);
char16_t c = 'a' + i - 10;
MOZ_ASSERT(StaticStrings::hasUnit(c));
return cx->staticStrings().getUnit(c);
}
if (JSFlatString* str = comp->dtoaCache.lookup(base, d))
return str;
size_t len;
numStr = Int32ToCString(&cbuf, i, &len, base);
MOZ_ASSERT(!cbuf.dbuf && numStr >= cbuf.sbuf && numStr < cbuf.sbuf + cbuf.sbufSize);
} else {
if (JSFlatString* str = comp->dtoaCache.lookup(base, d))
return str;
numStr = FracNumberToCString(cx, &cbuf, d, base);
if (!numStr) {
ReportOutOfMemory(cx);
return nullptr;
}
MOZ_ASSERT_IF(base == 10,
!cbuf.dbuf && numStr >= cbuf.sbuf && numStr < cbuf.sbuf + cbuf.sbufSize);
MOZ_ASSERT_IF(base != 10,
cbuf.dbuf && cbuf.dbuf == numStr);
}
JSFlatString* s = NewStringCopyZ<allowGC>(cx, numStr);
comp->dtoaCache.cache(base, d, s);
return s;
}
template <AllowGC allowGC>
JSString*
js::NumberToString(ExclusiveContext* cx, double d)
{
return NumberToStringWithBase<allowGC>(cx, d, 10);
}
template JSString*
js::NumberToString<CanGC>(ExclusiveContext* cx, double d);
template JSString*
js::NumberToString<NoGC>(ExclusiveContext* cx, double d);
JSAtom*
js::NumberToAtom(ExclusiveContext* cx, double d)
{
int32_t si;
if (mozilla::NumberIsInt32(d, &si))
return Int32ToAtom(cx, si);
if (JSFlatString* str = LookupDtoaCache(cx, d))
return AtomizeString(cx, str);
ToCStringBuf cbuf;
char* numStr = FracNumberToCString(cx, &cbuf, d);
if (!numStr) {
ReportOutOfMemory(cx);
return nullptr;
}
MOZ_ASSERT(!cbuf.dbuf && numStr >= cbuf.sbuf && numStr < cbuf.sbuf + cbuf.sbufSize);
size_t length = strlen(numStr);
JSAtom* atom = Atomize(cx, numStr, length);
if (!atom)
return nullptr;
CacheNumber(cx, d, atom);
return atom;
}
JSFlatString*
js::NumberToString(JSContext* cx, double d)
{
if (JSString* str = NumberToStringWithBase<CanGC>(cx, d, 10))
return &str->asFlat();
return nullptr;
}
JSFlatString*
js::IndexToString(JSContext* cx, uint32_t index)
{
if (StaticStrings::hasUint(index))
return cx->staticStrings().getUint(index);
JSCompartment* c = cx->compartment();
if (JSFlatString* str = c->dtoaCache.lookup(10, index))
return str;
Latin1Char buffer[JSFatInlineString::MAX_LENGTH_LATIN1 + 1];
RangedPtr<Latin1Char> end(buffer + JSFatInlineString::MAX_LENGTH_LATIN1,
buffer, JSFatInlineString::MAX_LENGTH_LATIN1 + 1);
*end = '\0';
RangedPtr<Latin1Char> start = BackfillIndexInCharBuffer(index, end);
mozilla::Range<const Latin1Char> chars(start.get(), end - start);
JSInlineString* str = NewInlineString<CanGC>(cx, chars);
if (!str)
return nullptr;
c->dtoaCache.cache(10, index, str);
return str;
}
bool JS_FASTCALL
js::NumberValueToStringBuffer(JSContext* cx, const Value& v, StringBuffer& sb)
{
/* Convert to C-string. */
ToCStringBuf cbuf;
const char* cstr;
size_t cstrlen;
if (v.isInt32()) {
cstr = Int32ToCString(&cbuf, v.toInt32(), &cstrlen);
MOZ_ASSERT(cstrlen == strlen(cstr));
} else {
cstr = NumberToCString(cx, &cbuf, v.toDouble());
if (!cstr) {
JS_ReportOutOfMemory(cx);
return false;
}
cstrlen = strlen(cstr);
}
/*
* Inflate to char16_t string. The input C-string characters are < 127, so
* even if char16_t units are UTF-8, all chars should map to one char16_t.
*/
MOZ_ASSERT(!cbuf.dbuf && cstrlen < cbuf.sbufSize);
return sb.append(cstr, cstrlen);
}
template <typename CharT>
static bool
CharsToNumber(ExclusiveContext* cx, const CharT* chars, size_t length, double* result)
{
if (length == 1) {
CharT c = chars[0];
if ('0' <= c && c <= '9')
*result = c - '0';
else if (unicode::IsSpace(c))
*result = 0.0;
else
*result = GenericNaN();
return true;
}
const CharT* end = chars + length;
const CharT* bp = SkipSpace(chars, end);
/* ECMA doesn't allow signed non-decimal numbers (bug 273467). */
if (end - bp >= 2 && bp[0] == '0') {
int radix = 0;
if (bp[1] == 'b' || bp[1] == 'B')
radix = 2;
else if (bp[1] == 'o' || bp[1] == 'O')
radix = 8;
else if (bp[1] == 'x' || bp[1] == 'X')
radix = 16;
if (radix != 0) {
/*
* It's probably a non-decimal number. Accept if there's at least one digit after
* the 0b|0o|0x, and if no non-whitespace characters follow all the digits.
*/
const CharT* endptr;
double d;
if (!GetPrefixInteger(cx, bp + 2, end, radix, &endptr, &d) ||
endptr == bp + 2 ||
SkipSpace(endptr, end) != end)
{
*result = GenericNaN();
} else {
*result = 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 CharT* ep;
double d;
if (!js_strtod(cx, bp, end, &ep, &d)) {
*result = GenericNaN();
return false;
}
if (SkipSpace(ep, end) != end)
*result = GenericNaN();
else
*result = d;
return true;
}
bool
js::StringToNumber(ExclusiveContext* cx, JSString* str, double* result)
{
AutoCheckCannotGC nogc;
JSLinearString* linearStr = str->ensureLinear(cx);
if (!linearStr)
return false;
return linearStr->hasLatin1Chars()
? CharsToNumber(cx, linearStr->latin1Chars(nogc), str->length(), result)
: CharsToNumber(cx, linearStr->twoByteChars(nogc), str->length(), result);
}
bool
js::ToNumberSlow(ExclusiveContext* cx, Value v, double* out)
{
MOZ_ASSERT(!v.isNumber());
goto skip_int_double;
for (;;) {
if (v.isNumber()) {
*out = v.toNumber();
return true;
}
skip_int_double:
if (!v.isObject()) {
if (v.isString())
return StringToNumber(cx, v.toString(), out);
if (v.isBoolean()) {
*out = v.toBoolean() ? 1.0 : 0.0;
return true;
}
if (v.isNull()) {
*out = 0.0;
return true;
}
if (v.isSymbol()) {
if (cx->isJSContext()) {
JS_ReportErrorNumber(cx->asJSContext(), GetErrorMessage, nullptr,
JSMSG_SYMBOL_TO_NUMBER);
}
return false;
}
MOZ_ASSERT(v.isUndefined());
*out = GenericNaN();
return true;
}
if (!cx->isJSContext())
return false;
RootedValue v2(cx, v);
if (!ToPrimitive(cx->asJSContext(), JSTYPE_NUMBER, &v2))
return false;
v = v2;
if (v.isObject())
break;
}
*out = GenericNaN();
return true;
}
JS_PUBLIC_API(bool)
js::ToNumberSlow(JSContext* cx, Value v, double* out)
{
return ToNumberSlow(static_cast<ExclusiveContext*>(cx), v, out);
}
/*
* Convert a value to an int8_t, according to the WebIDL rules for byte
* conversion. Return converted value in *out on success, false on failure.
*/
JS_PUBLIC_API(bool)
js::ToInt8Slow(JSContext *cx, const HandleValue v, int8_t *out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToInt8(d);
return true;
}
/*
* Convert a value to an int16_t, according to the WebIDL rules for short
* conversion. Return converted value in *out on success, false on failure.
*/
JS_PUBLIC_API(bool)
js::ToInt16Slow(JSContext *cx, const HandleValue v, int16_t *out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToInt16(d);
return true;
}
/*
* Convert a value to an int64_t, according to the WebIDL rules for long long
* conversion. Return converted value in *out on success, false on failure.
*/
JS_PUBLIC_API(bool)
js::ToInt64Slow(JSContext* cx, const HandleValue v, int64_t* out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToInt64(d);
return true;
}
/*
* Convert a value to an uint64_t, according to the WebIDL rules for unsigned long long
* conversion. Return converted value in *out on success, false on failure.
*/
JS_PUBLIC_API(bool)
js::ToUint64Slow(JSContext* cx, const HandleValue v, uint64_t* out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToUint64(d);
return true;
}
JS_PUBLIC_API(bool)
js::ToInt32Slow(JSContext* cx, const HandleValue v, int32_t* out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToInt32(d);
return true;
}
JS_PUBLIC_API(bool)
js::ToUint32Slow(JSContext* cx, const HandleValue v, uint32_t* out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumberSlow(cx, v, &d))
return false;
}
*out = ToUint32(d);
return true;
}
JS_PUBLIC_API(bool)
js::ToUint16Slow(JSContext* cx, const HandleValue v, uint16_t* out)
{
MOZ_ASSERT(!v.isInt32());
double d;
if (v.isDouble()) {
d = v.toDouble();
} else if (!ToNumberSlow(cx, v, &d)) {
return false;
}
if (d == 0 || !mozilla::IsFinite(d)) {
*out = 0;
return true;
}
uint16_t u = (uint16_t) d;
if ((double)u == d) {
*out = u;
return true;
}
bool neg = (d < 0);
d = floor(neg ? -d : d);
d = neg ? -d : d;
unsigned m = JS_BIT(16);
d = fmod(d, (double) m);
if (d < 0)
d += m;
*out = (uint16_t) d;
return true;
}
template<typename T>
bool
js::ToLengthClamped(T* cx, HandleValue v, uint32_t* out, bool* overflow)
{
if (v.isInt32()) {
int32_t i = v.toInt32();
*out = i < 0 ? 0 : i;
return true;
}
double d;
if (v.isDouble()) {
d = v.toDouble();
} else {
if (!ToNumber(cx, v, &d)) {
*overflow = false;
return false;
}
}
d = JS::ToInteger(d);
if (d <= 0.0) {
*out = 0;
return true;
}
if (d >= (double)0xFFFFFFFEU) {
*overflow = true;
return false;
}
*out = (uint32_t)d;
return true;
}
template bool
js::ToLengthClamped<JSContext>(JSContext*, HandleValue, uint32_t*, bool*);
template bool
js::ToLengthClamped<ExclusiveContext>(ExclusiveContext*, HandleValue, uint32_t*, bool*);
template <typename CharT>
bool
js_strtod(ExclusiveContext* cx, const CharT* begin, const CharT* end, const CharT** dEnd,
double* d)
{
const CharT* s = SkipSpace(begin, end);
size_t length = end - s;
Vector<char, 32> chars(cx);
if (!chars.growByUninitialized(length + 1))
return false;
size_t i = 0;
for (; i < length; i++) {
char16_t c = s[i];
if (c >> 8)
break;
chars[i] = char(c);
}
chars[i] = 0;
/* Try to parse +Infinity, -Infinity or Infinity. */
{
char* afterSign = chars.begin();
bool negative = (*afterSign == '-');
if (negative || *afterSign == '+')
afterSign++;
if (*afterSign == 'I' && !strncmp(afterSign, "Infinity", 8)) {
*d = negative ? NegativeInfinity<double>() : PositiveInfinity<double>();
*dEnd = s + (afterSign - chars.begin()) + 8;
return true;
}
}
/* Everything else. */
int err;
char* ep;
*d = js_strtod_harder(cx->dtoaState(), chars.begin(), &ep, &err);
MOZ_ASSERT(ep >= chars.begin());
if (ep == chars.begin())
*dEnd = begin;
else
*dEnd = s + (ep - chars.begin());
return true;
}
template bool
js_strtod(ExclusiveContext* cx, const char16_t* begin, const char16_t* end, const char16_t** dEnd,
double* d);
template bool
js_strtod(ExclusiveContext* cx, const Latin1Char* begin, const Latin1Char* end,
const Latin1Char** dEnd, double* d);