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jsnum.cpp
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* 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/ArrayUtils.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/Maybe.h"
#include "mozilla/RangedPtr.h"
#include "mozilla/TextUtils.h"
#include "mozilla/Utf8.h"
#ifdef HAVE_LOCALECONV
# include <locale.h>
#endif
#include <math.h>
#include <string.h>
#include "jstypes.h"
#include "builtin/String.h"
#include "double-conversion/double-conversion.h"
#include "js/CharacterEncoding.h"
#include "js/Conversions.h"
#if !EXPOSE_INTL_API
# include "js/LocaleSensitive.h"
#endif
#include "js/PropertySpec.h"
#include "util/DoubleToString.h"
#include "util/StringBuffer.h"
#include "vm/BigIntType.h"
#include "vm/GlobalObject.h"
#include "vm/JSAtom.h"
#include "vm/JSContext.h"
#include "vm/JSObject.h"
#include "vm/NativeObject-inl.h"
#include "vm/NumberObject-inl.h"
#include "vm/StringType-inl.h"
using namespace js;
using mozilla::Abs;
using mozilla::ArrayLength;
using mozilla::AsciiAlphanumericToNumber;
using mozilla::IsAsciiAlphanumeric;
using mozilla::IsAsciiDigit;
using mozilla::Maybe;
using mozilla::MinNumberValue;
using mozilla::NegativeInfinity;
using mozilla::PositiveInfinity;
using mozilla::RangedPtr;
using mozilla::Utf8AsUnsignedChars;
using mozilla::Utf8Unit;
using JS::AutoCheckCannotGC;
using JS::GenericNaN;
using JS::ToInt16;
using JS::ToInt32;
using JS::ToInt64;
using JS::ToInt8;
using JS::ToUint16;
using JS::ToUint32;
using JS::ToUint64;
using JS::ToUint8;
static bool EnsureDtoaState(JSContext* cx) {
if (!cx->dtoaState) {
cx->dtoaState = NewDtoaState();
if (!cx->dtoaState) {
return false;
}
}
return true;
}
/*
* 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(JSContext* cx, const CharT* start,
const CharT* end, double* dp) {
size_t length = end - start;
auto cstr = cx->make_pod_array<char>(length + 1);
if (!cstr) {
return false;
}
for (size_t i = 0; i < length; i++) {
char c = char(start[i]);
MOZ_ASSERT(IsAsciiAlphanumeric(c));
cstr[i] = c;
}
cstr[length] = 0;
if (!EnsureDtoaState(cx)) {
return false;
}
char* estr;
*dp = js_strtod_harder(cx->dtoaState, cstr.get(), &estr);
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(IsAsciiAlphanumeric(c));
digit = AsciiAlphanumericToNumber(c);
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.begin(), 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(JSContext* 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++) {
CharT c = *s;
if (!IsAsciiAlphanumeric(c)) {
break;
}
uint8_t digit = AsciiAlphanumericToNumber(c);
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;
}
namespace js {
template bool GetPrefixInteger(JSContext* cx, const char16_t* start,
const char16_t* end, int base,
const char16_t** endp, double* dp);
template bool GetPrefixInteger(JSContext* cx, const Latin1Char* start,
const Latin1Char* end, int base,
const Latin1Char** endp, double* dp);
} // namespace js
template <typename CharT>
bool js::GetDecimalInteger(JSContext* cx, const CharT* start, const CharT* end,
double* dp) {
MOZ_ASSERT(start <= end);
const CharT* s = start;
double d = 0.0;
for (; s < end; s++) {
CharT c = *s;
MOZ_ASSERT(IsAsciiDigit(c));
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);
}
namespace js {
template bool GetDecimalInteger(JSContext* cx, const char16_t* start,
const char16_t* end, double* dp);
template bool GetDecimalInteger(JSContext* cx, const Latin1Char* start,
const Latin1Char* end, double* dp);
template <>
bool GetDecimalInteger<Utf8Unit>(JSContext* cx, const Utf8Unit* start,
const Utf8Unit* end, double* dp) {
return GetDecimalInteger(cx, Utf8AsUnsignedChars(start),
Utf8AsUnsignedChars(end), dp);
}
} // namespace js
static bool num_parseFloat(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
if (args.length() == 0) {
args.rval().setNaN();
return true;
}
if (args[0].isNumber()) {
// ToString(-0) is "0", handle it accordingly.
if (args[0].isDouble() && args[0].toDouble() == 0.0) {
args.rval().setInt32(0);
} else {
args.rval().set(args[0]);
}
return true;
}
JSString* str = ToString<CanGC>(cx, args[0]);
if (!str) {
return false;
}
if (str->hasIndexValue()) {
args.rval().setNumber(str->getIndexValue());
return true;
}
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;
}
}
if (args[0].isString()) {
JSString* str = args[0].toString();
if (str->hasIndexValue()) {
args.rval().setNumber(str->getIndexValue());
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);
if (args.length() > 0) {
// BigInt proposal section 6.2, steps 2a-c.
if (!ToNumeric(cx, args[0])) {
return false;
}
if (args[0].isBigInt()) {
args[0].setNumber(BigInt::numberValue(args[0].toBigInt()));
}
MOZ_ASSERT(args[0].isNumber());
}
if (!args.isConstructing()) {
if (args.length() > 0) {
args.rval().set(args[0]);
} else {
args.rval().setInt32(0);
}
return true;
}
RootedObject proto(cx);
if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_Number, &proto)) {
return false;
}
double d = args.length() > 0 ? args[0].toNumber() : 0;
JSObject* obj = NumberObject::create(cx, d, 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();
}
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);
}
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(JSContext* cx, double d) {
if (Realm* realm = cx->realm()) {
if (JSFlatString* str = realm->dtoaCache.lookup(10, d)) {
return str;
}
}
return nullptr;
}
MOZ_ALWAYS_INLINE
static void CacheNumber(JSContext* cx, double d, JSFlatString* str) {
if (Realm* realm = cx->realm()) {
realm->dtoaCache.cache(10, d, str);
}
}
MOZ_ALWAYS_INLINE
static JSFlatString* LookupInt32ToString(JSContext* 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(JSContext* 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;
}
if (si >= 0) {
str->maybeInitializeIndex(si);
}
CacheNumber(cx, si, str);
return str;
}
template JSFlatString* js::Int32ToString<CanGC>(JSContext* cx, int32_t si);
template JSFlatString* js::Int32ToString<NoGC>(JSContext* cx, int32_t si);
JSFlatString* js::Int32ToStringHelperPure(JSContext* cx, int32_t si) {
AutoUnsafeCallWithABI unsafe;
JSFlatString* res = Int32ToString<NoGC>(cx, si);
if (!res) {
cx->recoverFromOutOfMemory();
}
return res;
}
JSAtom* js::Int32ToAtom(JSContext* 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);
Maybe<uint32_t> indexValue;
if (si >= 0) {
indexValue.emplace(si);
}
JSAtom* atom = Atomize(cx, start, length, js::DoNotPinAtom, indexValue);
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(JSContext* 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_ReportErrorNumberASCII(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.
*/
UniqueChars numBytes = EncodeAscii(cx, str);
if (!numBytes) {
return false;
}
const char* num = numBytes.get();
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, double prec,
int* precision) {
if (minPrecision <= prec && prec <= maxPrecision) {
*precision = int(prec);
return true;
}
ToCStringBuf cbuf;
if (char* numStr = NumberToCString(cx, &cbuf, prec, 10)) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_PRECISION_RANGE, numStr);
}
return false;
}
static bool DToStrResult(JSContext* cx, double d, JSDToStrMode mode,
int precision, const CallArgs& args) {
if (!EnsureDtoaState(cx)) {
return false;
}
char buf[DTOSTR_VARIABLE_BUFFER_SIZE(MAX_PRECISION + 1)];
char* numStr = js_dtostr(cx->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.
*/
// ES 2017 draft rev f8a9be8ea4bd97237d176907a1e3080dce20c68f 20.1.3.3.
MOZ_ALWAYS_INLINE bool num_toFixed_impl(JSContext* cx, const CallArgs& args) {
// Step 1.
MOZ_ASSERT(IsNumber(args.thisv()));
double d = Extract(args.thisv());
// Steps 2-3.
int precision;