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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
#include "builtin/String.h"
#include "mozilla/Attributes.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/Compiler.h"
#include "mozilla/FloatingPoint.h"
#if JS_HAS_INTL_API
# include "mozilla/intl/String.h"
#endif
#include "mozilla/Likely.h"
#include "mozilla/Maybe.h"
#include "mozilla/PodOperations.h"
#include "mozilla/Range.h"
#include "mozilla/SIMD.h"
#include "mozilla/TextUtils.h"
#include <algorithm>
#include <limits>
#include <string.h>
#include <type_traits>
#include "jsnum.h"
#include "jstypes.h"
#include "builtin/Array.h"
#if JS_HAS_INTL_API
# include "builtin/intl/CommonFunctions.h"
# include "builtin/intl/FormatBuffer.h"
#endif
#include "builtin/RegExp.h"
#include "jit/InlinableNatives.h"
#include "js/Conversions.h"
#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_*
#if !JS_HAS_INTL_API
# include "js/LocaleSensitive.h"
#endif
#include "js/Prefs.h"
#include "js/Printer.h"
#include "js/PropertyAndElement.h" // JS_DefineFunctions
#include "js/PropertySpec.h"
#include "js/StableStringChars.h"
#include "js/UniquePtr.h"
#include "util/StringBuffer.h"
#include "util/Unicode.h"
#include "vm/GlobalObject.h"
#include "vm/JSContext.h"
#include "vm/JSObject.h"
#include "vm/RegExpObject.h"
#include "vm/SelfHosting.h"
#include "vm/StaticStrings.h"
#include "vm/ToSource.h" // js::ValueToSource
#include "vm/GeckoProfiler-inl.h"
#include "vm/InlineCharBuffer-inl.h"
#include "vm/NativeObject-inl.h"
#include "vm/StringObject-inl.h"
#include "vm/StringType-inl.h"
using namespace js;
using JS::Symbol;
using JS::SymbolCode;
using mozilla::AsciiAlphanumericToNumber;
using mozilla::CheckedInt;
using mozilla::EnsureUtf16ValiditySpan;
using mozilla::IsAsciiHexDigit;
using mozilla::PodCopy;
using mozilla::RangedPtr;
using mozilla::SIMD;
using mozilla::Span;
using mozilla::Utf16ValidUpTo;
using JS::AutoCheckCannotGC;
using JS::AutoStableStringChars;
static JSLinearString* ArgToLinearString(JSContext* cx, const CallArgs& args,
unsigned argno) {
if (argno >= args.length()) {
return cx->names().undefined;
}
JSString* str = ToString<CanGC>(cx, args[argno]);
if (!str) {
return nullptr;
}
return str->ensureLinear(cx);
}
/*
* Forward declarations for URI encode/decode and helper routines
*/
static bool str_decodeURI(JSContext* cx, unsigned argc, Value* vp);
static bool str_decodeURI_Component(JSContext* cx, unsigned argc, Value* vp);
static bool str_encodeURI(JSContext* cx, unsigned argc, Value* vp);
static bool str_encodeURI_Component(JSContext* cx, unsigned argc, Value* vp);
/*
* Global string methods
*/
/* ES5 B.2.1 */
template <typename CharT>
static bool Escape(JSContext* cx, const CharT* chars, uint32_t length,
InlineCharBuffer<Latin1Char>& newChars,
uint32_t* newLengthOut) {
// clang-format off
static const uint8_t shouldPassThrough[128] = {
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,0,0,1,1,0,1,1,1, /* !"#$%&'()*+,-./ */
1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0, /* 0123456789:;<=>? */
1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* @ABCDEFGHIJKLMNO */
1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,1, /* PQRSTUVWXYZ[\]^_ */
0,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, /* `abcdefghijklmno */
1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0, /* pqrstuvwxyz{\}~ DEL */
};
// clang-format on
/* Take a first pass and see how big the result string will need to be. */
uint32_t newLength = length;
for (size_t i = 0; i < length; i++) {
char16_t ch = chars[i];
if (ch < 128 && shouldPassThrough[ch]) {
continue;
}
/*
* newlength is incremented below by at most 5 and at this point it must
* be a valid string length, so this should never overflow uint32_t.
*/
static_assert(JSString::MAX_LENGTH < UINT32_MAX - 5,
"Adding 5 to valid string length should not overflow");
MOZ_ASSERT(newLength <= JSString::MAX_LENGTH);
/* The character will be encoded as %XX or %uXXXX. */
newLength += (ch < 256) ? 2 : 5;
if (MOZ_UNLIKELY(newLength > JSString::MAX_LENGTH)) {
ReportAllocationOverflow(cx);
return false;
}
}
if (newLength == length) {
*newLengthOut = newLength;
return true;
}
if (!newChars.maybeAlloc(cx, newLength)) {
return false;
}
static const char digits[] = "0123456789ABCDEF";
Latin1Char* rawNewChars = newChars.get();
size_t i, ni;
for (i = 0, ni = 0; i < length; i++) {
char16_t ch = chars[i];
if (ch < 128 && shouldPassThrough[ch]) {
rawNewChars[ni++] = ch;
} else if (ch < 256) {
rawNewChars[ni++] = '%';
rawNewChars[ni++] = digits[ch >> 4];
rawNewChars[ni++] = digits[ch & 0xF];
} else {
rawNewChars[ni++] = '%';
rawNewChars[ni++] = 'u';
rawNewChars[ni++] = digits[ch >> 12];
rawNewChars[ni++] = digits[(ch & 0xF00) >> 8];
rawNewChars[ni++] = digits[(ch & 0xF0) >> 4];
rawNewChars[ni++] = digits[ch & 0xF];
}
}
MOZ_ASSERT(ni == newLength);
*newLengthOut = newLength;
return true;
}
static bool str_escape(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "escape");
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
InlineCharBuffer<Latin1Char> newChars;
uint32_t newLength = 0; // initialize to silence GCC warning
if (str->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
if (!Escape(cx, str->latin1Chars(nogc), str->length(), newChars,
&newLength)) {
return false;
}
} else {
AutoCheckCannotGC nogc;
if (!Escape(cx, str->twoByteChars(nogc), str->length(), newChars,
&newLength)) {
return false;
}
}
// Return input if no characters need to be escaped.
if (newLength == str->length()) {
args.rval().setString(str);
return true;
}
JSString* res = newChars.toString(cx, newLength);
if (!res) {
return false;
}
args.rval().setString(res);
return true;
}
template <typename CharT>
static inline bool Unhex4(const RangedPtr<const CharT> chars,
char16_t* result) {
CharT a = chars[0], b = chars[1], c = chars[2], d = chars[3];
if (!(IsAsciiHexDigit(a) && IsAsciiHexDigit(b) && IsAsciiHexDigit(c) &&
IsAsciiHexDigit(d))) {
return false;
}
char16_t unhex = AsciiAlphanumericToNumber(a);
unhex = (unhex << 4) + AsciiAlphanumericToNumber(b);
unhex = (unhex << 4) + AsciiAlphanumericToNumber(c);
unhex = (unhex << 4) + AsciiAlphanumericToNumber(d);
*result = unhex;
return true;
}
template <typename CharT>
static inline bool Unhex2(const RangedPtr<const CharT> chars,
char16_t* result) {
CharT a = chars[0], b = chars[1];
if (!(IsAsciiHexDigit(a) && IsAsciiHexDigit(b))) {
return false;
}
*result = (AsciiAlphanumericToNumber(a) << 4) + AsciiAlphanumericToNumber(b);
return true;
}
template <typename CharT>
static bool Unescape(StringBuffer& sb,
const mozilla::Range<const CharT> chars) {
// Step 2.
uint32_t length = chars.length();
/*
* Note that the spec algorithm has been optimized to avoid building
* a string in the case where no escapes are present.
*/
bool building = false;
#define ENSURE_BUILDING \
do { \
if (!building) { \
building = true; \
if (!sb.reserve(length)) return false; \
sb.infallibleAppend(chars.begin().get(), k); \
} \
} while (false);
// Step 4.
uint32_t k = 0;
// Step 5.
while (k < length) {
// Step 5.a.
char16_t c = chars[k];
// Step 5.b.
if (c == '%') {
static_assert(JSString::MAX_LENGTH < UINT32_MAX - 6,
"String length is not near UINT32_MAX");
// Steps 5.b.i-ii.
if (k + 6 <= length && chars[k + 1] == 'u') {
if (Unhex4(chars.begin() + k + 2, &c)) {
ENSURE_BUILDING
k += 5;
}
} else if (k + 3 <= length) {
if (Unhex2(chars.begin() + k + 1, &c)) {
ENSURE_BUILDING
k += 2;
}
}
}
// Step 5.c.
if (building && !sb.append(c)) {
return false;
}
// Step 5.d.
k += 1;
}
return true;
#undef ENSURE_BUILDING
}
// ES2018 draft rev f83aa38282c2a60c6916ebc410bfdf105a0f6a54
// B.2.1.2 unescape ( string )
static bool str_unescape(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "unescape");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1.
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
// Step 3.
JSStringBuilder sb(cx);
if (str->hasTwoByteChars() && !sb.ensureTwoByteChars()) {
return false;
}
// Steps 2, 4-5.
bool unescapeFailed = false;
if (str->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
unescapeFailed = !Unescape(sb, str->latin1Range(nogc));
} else {
AutoCheckCannotGC nogc;
unescapeFailed = !Unescape(sb, str->twoByteRange(nogc));
}
if (unescapeFailed) {
return false;
}
// Step 6.
JSLinearString* result;
if (!sb.empty()) {
result = sb.finishString();
if (!result) {
return false;
}
} else {
result = str;
}
args.rval().setString(result);
return true;
}
static bool str_uneval(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
JSString* str = ValueToSource(cx, args.get(0));
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
static const JSFunctionSpec string_functions[] = {
JS_FN("escape", str_escape, 1, JSPROP_RESOLVING),
JS_FN("unescape", str_unescape, 1, JSPROP_RESOLVING),
JS_FN("uneval", str_uneval, 1, JSPROP_RESOLVING),
JS_FN("decodeURI", str_decodeURI, 1, JSPROP_RESOLVING),
JS_FN("encodeURI", str_encodeURI, 1, JSPROP_RESOLVING),
JS_FN("decodeURIComponent", str_decodeURI_Component, 1, JSPROP_RESOLVING),
JS_FN("encodeURIComponent", str_encodeURI_Component, 1, JSPROP_RESOLVING),
JS_FS_END,
};
static const unsigned STRING_ELEMENT_ATTRS =
JSPROP_ENUMERATE | JSPROP_READONLY | JSPROP_PERMANENT;
static bool str_enumerate(JSContext* cx, HandleObject obj) {
RootedString str(cx, obj->as<StringObject>().unbox());
js::StaticStrings& staticStrings = cx->staticStrings();
RootedValue value(cx);
for (size_t i = 0, length = str->length(); i < length; i++) {
JSString* str1 = staticStrings.getUnitStringForElement(cx, str, i);
if (!str1) {
return false;
}
value.setString(str1);
if (!DefineDataElement(cx, obj, i, value,
STRING_ELEMENT_ATTRS | JSPROP_RESOLVING)) {
return false;
}
}
return true;
}
static bool str_mayResolve(const JSAtomState&, jsid id, JSObject*) {
// str_resolve ignores non-integer ids.
return id.isInt();
}
static bool str_resolve(JSContext* cx, HandleObject obj, HandleId id,
bool* resolvedp) {
if (!id.isInt()) {
return true;
}
RootedString str(cx, obj->as<StringObject>().unbox());
int32_t slot = id.toInt();
if ((size_t)slot < str->length()) {
JSString* str1 =
cx->staticStrings().getUnitStringForElement(cx, str, size_t(slot));
if (!str1) {
return false;
}
RootedValue value(cx, StringValue(str1));
if (!DefineDataElement(cx, obj, uint32_t(slot), value,
STRING_ELEMENT_ATTRS | JSPROP_RESOLVING)) {
return false;
}
*resolvedp = true;
}
return true;
}
static const JSClassOps StringObjectClassOps = {
nullptr, // addProperty
nullptr, // delProperty
str_enumerate, // enumerate
nullptr, // newEnumerate
str_resolve, // resolve
str_mayResolve, // mayResolve
nullptr, // finalize
nullptr, // call
nullptr, // construct
nullptr, // trace
};
const JSClass StringObject::class_ = {
"String",
JSCLASS_HAS_RESERVED_SLOTS(StringObject::RESERVED_SLOTS) |
JSCLASS_HAS_CACHED_PROTO(JSProto_String),
&StringObjectClassOps, &StringObject::classSpec_};
/*
* Perform the initial |RequireObjectCoercible(thisv)| and |ToString(thisv)|
* from nearly all String.prototype.* functions.
*/
static MOZ_ALWAYS_INLINE JSString* ToStringForStringFunction(
JSContext* cx, const char* funName, HandleValue thisv) {
if (thisv.isString()) {
return thisv.toString();
}
if (thisv.isObject()) {
if (thisv.toObject().is<StringObject>()) {
StringObject* nobj = &thisv.toObject().as<StringObject>();
// We have to make sure that the ToPrimitive call from ToString
// would be unobservable.
if (HasNoToPrimitiveMethodPure(nobj, cx) &&
HasNativeMethodPure(nobj, cx->names().toString, str_toString, cx)) {
return nobj->unbox();
}
}
} else if (thisv.isNullOrUndefined()) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_INCOMPATIBLE_PROTO, "String", funName,
thisv.isNull() ? "null" : "undefined");
return nullptr;
}
return ToStringSlow<CanGC>(cx, thisv);
}
MOZ_ALWAYS_INLINE bool IsString(HandleValue v) {
return v.isString() || (v.isObject() && v.toObject().is<StringObject>());
}
MOZ_ALWAYS_INLINE bool str_toSource_impl(JSContext* cx, const CallArgs& args) {
MOZ_ASSERT(IsString(args.thisv()));
JSString* str = ToString<CanGC>(cx, args.thisv());
if (!str) {
return false;
}
UniqueChars quoted = QuoteString(cx, str, '"');
if (!quoted) {
return false;
}
JSStringBuilder sb(cx);
if (!sb.append("(new String(") ||
!sb.append(quoted.get(), strlen(quoted.get())) || !sb.append("))")) {
return false;
}
JSString* result = sb.finishString();
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
static bool str_toSource(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsString, str_toSource_impl>(cx, args);
}
MOZ_ALWAYS_INLINE bool str_toString_impl(JSContext* cx, const CallArgs& args) {
MOZ_ASSERT(IsString(args.thisv()));
args.rval().setString(
args.thisv().isString()
? args.thisv().toString()
: args.thisv().toObject().as<StringObject>().unbox());
return true;
}
bool js::str_toString(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
return CallNonGenericMethod<IsString, str_toString_impl>(cx, args);
}
template <typename DestChar, typename SrcChar>
static inline void CopyChars(DestChar* destChars, const SrcChar* srcChars,
size_t length) {
if constexpr (std::is_same_v<DestChar, SrcChar>) {
#if MOZ_IS_GCC
memcpy(destChars, srcChars, length * sizeof(DestChar));
#else
PodCopy(destChars, srcChars, length);
#endif
} else {
for (size_t i = 0; i < length; i++) {
destChars[i] = srcChars[i];
}
}
}
template <typename CharT>
static inline void CopyChars(CharT* to, const JSLinearString* from,
size_t begin, size_t length) {
MOZ_ASSERT(begin + length <= from->length());
JS::AutoCheckCannotGC nogc;
if (from->hasLatin1Chars()) {
CopyChars(to, from->latin1Chars(nogc) + begin, length);
} else {
CopyChars(to, from->twoByteChars(nogc) + begin, length);
}
}
template <typename CharT>
static JSLinearString* SubstringInlineString(JSContext* cx,
Handle<JSLinearString*> left,
Handle<JSLinearString*> right,
size_t begin, size_t lhsLength,
size_t rhsLength) {
constexpr size_t MaxLength = std::is_same_v<CharT, Latin1Char>
? JSFatInlineString::MAX_LENGTH_LATIN1
: JSFatInlineString::MAX_LENGTH_TWO_BYTE;
size_t length = lhsLength + rhsLength;
MOZ_ASSERT(length <= MaxLength, "total length fits in stack chars");
MOZ_ASSERT(JSInlineString::lengthFits<CharT>(length));
CharT chars[MaxLength] = {};
CopyChars(chars, left, begin, lhsLength);
CopyChars(chars + lhsLength, right, 0, rhsLength);
if (auto* str = cx->staticStrings().lookup(chars, length)) {
return str;
}
return NewInlineString<CanGC>(cx, chars, length);
}
JSString* js::SubstringKernel(JSContext* cx, HandleString str, int32_t beginInt,
int32_t lengthInt) {
MOZ_ASSERT(0 <= beginInt);
MOZ_ASSERT(0 <= lengthInt);
MOZ_ASSERT(uint32_t(beginInt) <= str->length());
MOZ_ASSERT(uint32_t(lengthInt) <= str->length() - beginInt);
uint32_t begin = beginInt;
uint32_t len = lengthInt;
/*
* Optimization for one level deep ropes.
* This is common for the following pattern:
*
* while() {
* text = text.substr(0, x) + "bla" + text.substr(x)
* text.charCodeAt(x + 1)
* }
*/
if (str->isRope()) {
JSRope* rope = &str->asRope();
/* Substring is totally in leftChild of rope. */
if (begin + len <= rope->leftChild()->length()) {
return NewDependentString(cx, rope->leftChild(), begin, len);
}
/* Substring is totally in rightChild of rope. */
if (begin >= rope->leftChild()->length()) {
begin -= rope->leftChild()->length();
return NewDependentString(cx, rope->rightChild(), begin, len);
}
/*
* Requested substring is partly in the left and partly in right child.
* Create a rope of substrings for both childs.
*/
MOZ_ASSERT(begin < rope->leftChild()->length() &&
begin + len > rope->leftChild()->length());
size_t lhsLength = rope->leftChild()->length() - begin;
size_t rhsLength = begin + len - rope->leftChild()->length();
Rooted<JSLinearString*> left(cx, rope->leftChild()->ensureLinear(cx));
if (!left) {
return nullptr;
}
Rooted<JSLinearString*> right(cx, rope->rightChild()->ensureLinear(cx));
if (!right) {
return nullptr;
}
if (rope->hasLatin1Chars()) {
if (JSInlineString::lengthFits<Latin1Char>(len)) {
return SubstringInlineString<Latin1Char>(cx, left, right, begin,
lhsLength, rhsLength);
}
} else {
if (JSInlineString::lengthFits<char16_t>(len)) {
return SubstringInlineString<char16_t>(cx, left, right, begin,
lhsLength, rhsLength);
}
}
left = NewDependentString(cx, left, begin, lhsLength);
if (!left) {
return nullptr;
}
right = NewDependentString(cx, right, 0, rhsLength);
if (!right) {
return nullptr;
}
// The dependent string of a two-byte string can be a Latin-1 string, so
// check again if the result fits into an inline string.
if (left->hasLatin1Chars() && right->hasLatin1Chars()) {
if (JSInlineString::lengthFits<Latin1Char>(len)) {
MOZ_ASSERT(str->hasTwoByteChars(), "Latin-1 ropes are handled above");
return SubstringInlineString<Latin1Char>(cx, left, right, 0, lhsLength,
rhsLength);
}
}
return JSRope::new_<CanGC>(cx, left, right, len);
}
return NewDependentString(cx, str, begin, len);
}
/**
* U+03A3 GREEK CAPITAL LETTER SIGMA has two different lower case mappings
* depending on its context:
* When it's preceded by a cased character and not followed by another cased
* character, its lower case form is U+03C2 GREEK SMALL LETTER FINAL SIGMA.
* Otherwise its lower case mapping is U+03C3 GREEK SMALL LETTER SIGMA.
*
* Unicode 9.0, §3.13 Default Case Algorithms
*/
static char16_t Final_Sigma(const char16_t* chars, size_t length,
size_t index) {
MOZ_ASSERT(index < length);
MOZ_ASSERT(chars[index] == unicode::GREEK_CAPITAL_LETTER_SIGMA);
MOZ_ASSERT(unicode::ToLowerCase(unicode::GREEK_CAPITAL_LETTER_SIGMA) ==
unicode::GREEK_SMALL_LETTER_SIGMA);
#if JS_HAS_INTL_API
// Tell the analysis the BinaryProperty.contains function pointer called by
// mozilla::intl::String::Is{CaseIgnorable, Cased} cannot GC.
JS::AutoSuppressGCAnalysis nogc;
bool precededByCased = false;
for (size_t i = index; i > 0;) {
char16_t c = chars[--i];
char32_t codePoint = c;
if (unicode::IsTrailSurrogate(c) && i > 0) {
char16_t lead = chars[i - 1];
if (unicode::IsLeadSurrogate(lead)) {
codePoint = unicode::UTF16Decode(lead, c);
i--;
}
}
// Ignore any characters with the property Case_Ignorable.
// NB: We need to skip over all Case_Ignorable characters, even when
// they also have the Cased binary property.
if (mozilla::intl::String::IsCaseIgnorable(codePoint)) {
continue;
}
precededByCased = mozilla::intl::String::IsCased(codePoint);
break;
}
if (!precededByCased) {
return unicode::GREEK_SMALL_LETTER_SIGMA;
}
bool followedByCased = false;
for (size_t i = index + 1; i < length;) {
char16_t c = chars[i++];
char32_t codePoint = c;
if (unicode::IsLeadSurrogate(c) && i < length) {
char16_t trail = chars[i];
if (unicode::IsTrailSurrogate(trail)) {
codePoint = unicode::UTF16Decode(c, trail);
i++;
}
}
// Ignore any characters with the property Case_Ignorable.
// NB: We need to skip over all Case_Ignorable characters, even when
// they also have the Cased binary property.
if (mozilla::intl::String::IsCaseIgnorable(codePoint)) {
continue;
}
followedByCased = mozilla::intl::String::IsCased(codePoint);
break;
}
if (!followedByCased) {
return unicode::GREEK_SMALL_LETTER_FINAL_SIGMA;
}
#endif
return unicode::GREEK_SMALL_LETTER_SIGMA;
}
// If |srcLength == destLength| is true, the destination buffer was allocated
// with the same size as the source buffer. When we append characters which
// have special casing mappings, we test |srcLength == destLength| to decide
// if we need to back out and reallocate a sufficiently large destination
// buffer. Otherwise the destination buffer was allocated with the correct
// size to hold all lower case mapped characters, i.e.
// |destLength == ToLowerCaseLength(srcChars, 0, srcLength)| is true.
template <typename CharT>
static size_t ToLowerCaseImpl(CharT* destChars, const CharT* srcChars,
size_t startIndex, size_t srcLength,
size_t destLength) {
MOZ_ASSERT(startIndex < srcLength);
MOZ_ASSERT(srcLength <= destLength);
if constexpr (std::is_same_v<CharT, Latin1Char>) {
MOZ_ASSERT(srcLength == destLength);
}
size_t j = startIndex;
for (size_t i = startIndex; i < srcLength; i++) {
CharT c = srcChars[i];
if constexpr (!std::is_same_v<CharT, Latin1Char>) {
if (unicode::IsLeadSurrogate(c) && i + 1 < srcLength) {
char16_t trail = srcChars[i + 1];
if (unicode::IsTrailSurrogate(trail)) {
trail = unicode::ToLowerCaseNonBMPTrail(c, trail);
destChars[j++] = c;
destChars[j++] = trail;
i++;
continue;
}
}
// Special case: U+0130 LATIN CAPITAL LETTER I WITH DOT ABOVE
// lowercases to <U+0069 U+0307>.
if (c == unicode::LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE) {
// Return if the output buffer is too small.
if (srcLength == destLength) {
return i;
}
destChars[j++] = CharT('i');
destChars[j++] = CharT(unicode::COMBINING_DOT_ABOVE);
continue;
}
// Special case: U+03A3 GREEK CAPITAL LETTER SIGMA lowercases to
// one of two codepoints depending on context.
if (c == unicode::GREEK_CAPITAL_LETTER_SIGMA) {
destChars[j++] = Final_Sigma(srcChars, srcLength, i);
continue;
}
}
c = unicode::ToLowerCase(c);
destChars[j++] = c;
}
MOZ_ASSERT(j == destLength);
return srcLength;
}
static size_t ToLowerCaseLength(const char16_t* chars, size_t startIndex,
size_t length) {
size_t lowerLength = length;
for (size_t i = startIndex; i < length; i++) {
char16_t c = chars[i];
// U+0130 is lowercased to the two-element sequence <U+0069 U+0307>.
if (c == unicode::LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE) {
lowerLength += 1;
}
}
return lowerLength;
}
template <typename CharT>
static JSString* ToLowerCase(JSContext* cx, JSLinearString* str) {
// Unlike toUpperCase, toLowerCase has the nice invariant that if the
// input is a Latin-1 string, the output is also a Latin-1 string.
InlineCharBuffer<CharT> newChars;
const size_t length = str->length();
size_t resultLength;
{
AutoCheckCannotGC nogc;
const CharT* chars = str->chars<CharT>(nogc);
// We don't need extra special casing checks in the loop below,
// because U+0130 LATIN CAPITAL LETTER I WITH DOT ABOVE and U+03A3
// GREEK CAPITAL LETTER SIGMA already have simple lower case mappings.
MOZ_ASSERT(unicode::ChangesWhenLowerCased(
unicode::LATIN_CAPITAL_LETTER_I_WITH_DOT_ABOVE),
"U+0130 has a simple lower case mapping");
MOZ_ASSERT(
unicode::ChangesWhenLowerCased(unicode::GREEK_CAPITAL_LETTER_SIGMA),
"U+03A3 has a simple lower case mapping");
// One element Latin-1 strings can be directly retrieved from the
// static strings cache.
if constexpr (std::is_same_v<CharT, Latin1Char>) {
if (length == 1) {
CharT lower = unicode::ToLowerCase(chars[0]);
MOZ_ASSERT(StaticStrings::hasUnit(lower));
return cx->staticStrings().getUnit(lower);
}
}
// Look for the first character that changes when lowercased.
size_t i = 0;
for (; i < length; i++) {
CharT c = chars[i];
if constexpr (!std::is_same_v<CharT, Latin1Char>) {
if (unicode::IsLeadSurrogate(c) && i + 1 < length) {
CharT trail = chars[i + 1];
if (unicode::IsTrailSurrogate(trail)) {
if (unicode::ChangesWhenLowerCasedNonBMP(c, trail)) {
break;
}
i++;
continue;
}
}
}
if (unicode::ChangesWhenLowerCased(c)) {
break;
}
}
// If no character needs to change, return the input string.
if (i == length) {
return str;
}
resultLength = length;
if (!newChars.maybeAlloc(cx, resultLength)) {
return nullptr;
}
PodCopy(newChars.get(), chars, i);
size_t readChars =
ToLowerCaseImpl(newChars.get(), chars, i, length, resultLength);
if constexpr (!std::is_same_v<CharT, Latin1Char>) {
if (readChars < length) {
resultLength = ToLowerCaseLength(chars, readChars, length);
if (!newChars.maybeRealloc(cx, length, resultLength)) {
return nullptr;
}
MOZ_ALWAYS_TRUE(length == ToLowerCaseImpl(newChars.get(), chars,
readChars, length,
resultLength));
}
} else {
MOZ_ASSERT(readChars == length,
"Latin-1 strings don't have special lower case mappings");
}
}
return newChars.toStringDontDeflate(cx, resultLength);
}
JSString* js::StringToLowerCase(JSContext* cx, HandleString string) {
JSLinearString* linear = string->ensureLinear(cx);
if (!linear) {
return nullptr;
}
if (linear->hasLatin1Chars()) {
return ToLowerCase<Latin1Char>(cx, linear);
}
return ToLowerCase<char16_t>(cx, linear);
}
static bool str_toLowerCase(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "toLowerCase");
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(cx,
ToStringForStringFunction(cx, "toLowerCase", args.thisv()));
if (!str) {
return false;
}
JSString* result = StringToLowerCase(cx, str);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#if JS_HAS_INTL_API
// String.prototype.toLocaleLowerCase is self-hosted when Intl is exposed,
// with core functionality performed by the intrinsic below.
static const char* CaseMappingLocale(JSContext* cx, JSString* str) {
JSLinearString* locale = str->ensureLinear(cx);
if (!locale) {
return nullptr;
}
MOZ_ASSERT(locale->length() >= 2, "locale is a valid language tag");
// Lithuanian, Turkish, and Azeri have language dependent case mappings.
static const char languagesWithSpecialCasing[][3] = {"lt", "tr", "az"};
// All strings in |languagesWithSpecialCasing| are of length two, so we
// only need to compare the first two characters to find a matching locale.
// ES2017 Intl, §9.2.2 BestAvailableLocale
if (locale->length() == 2 || locale->latin1OrTwoByteChar(2) == '-') {
for (const auto& language : languagesWithSpecialCasing) {
if (locale->latin1OrTwoByteChar(0) == language[0] &&
locale->latin1OrTwoByteChar(1) == language[1]) {
return language;
}
}
}
return ""; // ICU root locale
}
static bool HasDefaultCasing(const char* locale) { return !strcmp(locale, ""); }
bool js::intl_toLocaleLowerCase(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
MOZ_ASSERT(args.length() == 2);
MOZ_ASSERT(args[0].isString());
MOZ_ASSERT(args[1].isString());
RootedString string(cx, args[0].toString());
const char* locale = CaseMappingLocale(cx, args[1].toString());
if (!locale) {
return false;
}
// Call String.prototype.toLowerCase() for language independent casing.
if (HasDefaultCasing(locale)) {
JSString* str = StringToLowerCase(cx, string);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
AutoStableStringChars inputChars(cx);
if (!inputChars.initTwoByte(cx, string)) {
return false;
}
mozilla::Range<const char16_t> input = inputChars.twoByteRange();
// Note: maximum case mapping length is three characters, so the result
// length might be > INT32_MAX. ICU will fail in this case.
static_assert(JSString::MAX_LENGTH <= INT32_MAX,
"String length must fit in int32_t for ICU");
static const size_t INLINE_CAPACITY = js::intl::INITIAL_CHAR_BUFFER_SIZE;
intl::FormatBuffer<char16_t, INLINE_CAPACITY> buffer(cx);
auto ok = mozilla::intl::String::ToLocaleLowerCase(locale, input, buffer);
if (ok.isErr()) {
intl::ReportInternalError(cx, ok.unwrapErr());
return false;
}
JSString* result = buffer.toString(cx);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#else
// When the Intl API is not exposed, String.prototype.toLowerCase is implemented
// in C++.
static bool str_toLocaleLowerCase(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype",
"toLocaleLowerCase");
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(
cx, ToStringForStringFunction(cx, "toLocaleLowerCase", args.thisv()));
if (!str) {
return false;
}
/*
* Forcefully ignore the first (or any) argument and return toLowerCase(),
* ECMA has reserved that argument, presumably for defining the locale.
*/
if (cx->runtime()->localeCallbacks &&
cx->runtime()->localeCallbacks->localeToLowerCase) {
RootedValue result(cx);
if (!cx->runtime()->localeCallbacks->localeToLowerCase(cx, str, &result)) {
return false;
}
args.rval().set(result);
return true;
}
Rooted<JSLinearString*> linear(cx, str->ensureLinear(cx));
if (!linear) {
return false;
}
JSString* result = StringToLowerCase(cx, linear);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#endif // JS_HAS_INTL_API
static inline bool ToUpperCaseHasSpecialCasing(Latin1Char charCode) {
// U+00DF LATIN SMALL LETTER SHARP S is the only Latin-1 code point with
// special casing rules, so detect it inline.
bool hasUpperCaseSpecialCasing =
charCode == unicode::LATIN_SMALL_LETTER_SHARP_S;
MOZ_ASSERT(hasUpperCaseSpecialCasing ==
unicode::ChangesWhenUpperCasedSpecialCasing(charCode));
return hasUpperCaseSpecialCasing;
}
static inline bool ToUpperCaseHasSpecialCasing(char16_t charCode) {
return unicode::ChangesWhenUpperCasedSpecialCasing(charCode);
}
static inline size_t ToUpperCaseLengthSpecialCasing(Latin1Char charCode) {
// U+00DF LATIN SMALL LETTER SHARP S is uppercased to two 'S'.
MOZ_ASSERT(charCode == unicode::LATIN_SMALL_LETTER_SHARP_S);
return 2;
}
static inline size_t ToUpperCaseLengthSpecialCasing(char16_t charCode) {
MOZ_ASSERT(ToUpperCaseHasSpecialCasing(charCode));
return unicode::LengthUpperCaseSpecialCasing(charCode);
}
static inline void ToUpperCaseAppendUpperCaseSpecialCasing(char16_t charCode,
Latin1Char* elements,
size_t* index) {
// U+00DF LATIN SMALL LETTER SHARP S is uppercased to two 'S'.
MOZ_ASSERT(charCode == unicode::LATIN_SMALL_LETTER_SHARP_S);
static_assert('S' <= JSString::MAX_LATIN1_CHAR, "'S' is a Latin-1 character");
elements[(*index)++] = 'S';
elements[(*index)++] = 'S';
}
static inline void ToUpperCaseAppendUpperCaseSpecialCasing(char16_t charCode,
char16_t* elements,
size_t* index) {
unicode::AppendUpperCaseSpecialCasing(charCode, elements, index);
}
// See ToLowerCaseImpl for an explanation of the parameters.
template <typename DestChar, typename SrcChar>
static size_t ToUpperCaseImpl(DestChar* destChars, const SrcChar* srcChars,
size_t startIndex, size_t srcLength,
size_t destLength) {
static_assert(std::is_same_v<SrcChar, Latin1Char> ||
!std::is_same_v<DestChar, Latin1Char>,
"cannot write non-Latin-1 characters into Latin-1 string");
MOZ_ASSERT(startIndex < srcLength);
MOZ_ASSERT(srcLength <= destLength);
size_t j = startIndex;
for (size_t i = startIndex; i < srcLength; i++) {
char16_t c = srcChars[i];
if constexpr (!std::is_same_v<DestChar, Latin1Char>) {
if (unicode::IsLeadSurrogate(c) && i + 1 < srcLength) {
char16_t trail = srcChars[i + 1];
if (unicode::IsTrailSurrogate(trail)) {
trail = unicode::ToUpperCaseNonBMPTrail(c, trail);
destChars[j++] = c;
destChars[j++] = trail;
i++;
continue;
}
}
}
if (MOZ_UNLIKELY(c > 0x7f &&
ToUpperCaseHasSpecialCasing(static_cast<SrcChar>(c)))) {
// Return if the output buffer is too small.
if (srcLength == destLength) {
return i;
}
ToUpperCaseAppendUpperCaseSpecialCasing(c, destChars, &j);
continue;
}
c = unicode::ToUpperCase(c);
if constexpr (std::is_same_v<DestChar, Latin1Char>) {
MOZ_ASSERT(c <= JSString::MAX_LATIN1_CHAR);
}
destChars[j++] = c;
}
MOZ_ASSERT(j == destLength);
return srcLength;
}
template <typename CharT>
static size_t ToUpperCaseLength(const CharT* chars, size_t startIndex,
size_t length) {
size_t upperLength = length;
for (size_t i = startIndex; i < length; i++) {
char16_t c = chars[i];
if (c > 0x7f && ToUpperCaseHasSpecialCasing(static_cast<CharT>(c))) {
upperLength += ToUpperCaseLengthSpecialCasing(static_cast<CharT>(c)) - 1;
}
}
return upperLength;
}
template <typename DestChar, typename SrcChar>
static inline bool ToUpperCase(JSContext* cx,
InlineCharBuffer<DestChar>& newChars,
const SrcChar* chars, size_t startIndex,
size_t length, size_t* resultLength) {
MOZ_ASSERT(startIndex < length);
*resultLength = length;
if (!newChars.maybeAlloc(cx, length)) {
return false;
}
CopyChars(newChars.get(), chars, startIndex);
size_t readChars =
ToUpperCaseImpl(newChars.get(), chars, startIndex, length, length);
if (readChars < length) {
size_t actualLength = ToUpperCaseLength(chars, readChars, length);
*resultLength = actualLength;
if (!newChars.maybeRealloc(cx, length, actualLength)) {
return false;
}
MOZ_ALWAYS_TRUE(length == ToUpperCaseImpl(newChars.get(), chars, readChars,
length, actualLength));
}
return true;
}
template <typename CharT>
static JSString* ToUpperCase(JSContext* cx, JSLinearString* str) {
using Latin1Buffer = InlineCharBuffer<Latin1Char>;
using TwoByteBuffer = InlineCharBuffer<char16_t>;
mozilla::MaybeOneOf<Latin1Buffer, TwoByteBuffer> newChars;
const size_t length = str->length();
size_t resultLength;
{
AutoCheckCannotGC nogc;
const CharT* chars = str->chars<CharT>(nogc);
// Most one element Latin-1 strings can be directly retrieved from the
// static strings cache.
if constexpr (std::is_same_v<CharT, Latin1Char>) {
if (length == 1) {
Latin1Char c = chars[0];
if (c != unicode::MICRO_SIGN &&
c != unicode::LATIN_SMALL_LETTER_Y_WITH_DIAERESIS &&
c != unicode::LATIN_SMALL_LETTER_SHARP_S) {
char16_t upper = unicode::ToUpperCase(c);
MOZ_ASSERT(upper <= JSString::MAX_LATIN1_CHAR);
MOZ_ASSERT(StaticStrings::hasUnit(upper));
return cx->staticStrings().getUnit(upper);
}
MOZ_ASSERT(unicode::ToUpperCase(c) > JSString::MAX_LATIN1_CHAR ||
ToUpperCaseHasSpecialCasing(c));
}
}
// Look for the first character that changes when uppercased.
size_t i = 0;
for (; i < length; i++) {
CharT c = chars[i];
if constexpr (!std::is_same_v<CharT, Latin1Char>) {
if (unicode::IsLeadSurrogate(c) && i + 1 < length) {
CharT trail = chars[i + 1];
if (unicode::IsTrailSurrogate(trail)) {
if (unicode::ChangesWhenUpperCasedNonBMP(c, trail)) {
break;
}
i++;
continue;
}
}
}
if (unicode::ChangesWhenUpperCased(c)) {
break;
}
if (MOZ_UNLIKELY(c > 0x7f && ToUpperCaseHasSpecialCasing(c))) {
break;
}
}
// If no character needs to change, return the input string.
if (i == length) {
return str;
}
// The string changes when uppercased, so we must create a new string.
// Can it be Latin-1?
//
// If the original string is Latin-1, it can -- unless the string
// contains U+00B5 MICRO SIGN or U+00FF SMALL LETTER Y WITH DIAERESIS,
// the only Latin-1 codepoints that don't uppercase within Latin-1.
// Search for those codepoints to decide whether the new string can be
// Latin-1.
// If the original string is a two-byte string, its uppercase form is
// so rarely Latin-1 that we don't even consider creating a new
// Latin-1 string.
if constexpr (std::is_same_v<CharT, Latin1Char>) {
bool resultIsLatin1 = std::none_of(chars + i, chars + length, [](auto c) {
bool upperCaseIsTwoByte =
c == unicode::MICRO_SIGN ||
c == unicode::LATIN_SMALL_LETTER_Y_WITH_DIAERESIS;
MOZ_ASSERT(upperCaseIsTwoByte ==
(unicode::ToUpperCase(c) > JSString::MAX_LATIN1_CHAR));
return upperCaseIsTwoByte;
});
if (resultIsLatin1) {
newChars.construct<Latin1Buffer>();
if (!ToUpperCase(cx, newChars.ref<Latin1Buffer>(), chars, i, length,
&resultLength)) {
return nullptr;
}
} else {
newChars.construct<TwoByteBuffer>();
if (!ToUpperCase(cx, newChars.ref<TwoByteBuffer>(), chars, i, length,
&resultLength)) {
return nullptr;
}
}
} else {
newChars.construct<TwoByteBuffer>();
if (!ToUpperCase(cx, newChars.ref<TwoByteBuffer>(), chars, i, length,
&resultLength)) {
return nullptr;
}
}
}
auto toString = [&](auto& chars) {
return chars.toStringDontDeflate(cx, resultLength);
};
return newChars.mapNonEmpty(toString);
}
JSString* js::StringToUpperCase(JSContext* cx, HandleString string) {
JSLinearString* linear = string->ensureLinear(cx);
if (!linear) {
return nullptr;
}
if (linear->hasLatin1Chars()) {
return ToUpperCase<Latin1Char>(cx, linear);
}
return ToUpperCase<char16_t>(cx, linear);
}
static bool str_toUpperCase(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "toUpperCase");
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(cx,
ToStringForStringFunction(cx, "toUpperCase", args.thisv()));
if (!str) {
return false;
}
JSString* result = StringToUpperCase(cx, str);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#if JS_HAS_INTL_API
// String.prototype.toLocaleUpperCase is self-hosted when Intl is exposed,
// with core functionality performed by the intrinsic below.
bool js::intl_toLocaleUpperCase(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
MOZ_ASSERT(args.length() == 2);
MOZ_ASSERT(args[0].isString());
MOZ_ASSERT(args[1].isString());
RootedString string(cx, args[0].toString());
const char* locale = CaseMappingLocale(cx, args[1].toString());
if (!locale) {
return false;
}
// Call String.prototype.toUpperCase() for language independent casing.
if (HasDefaultCasing(locale)) {
JSString* str = js::StringToUpperCase(cx, string);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
AutoStableStringChars inputChars(cx);
if (!inputChars.initTwoByte(cx, string)) {
return false;
}
mozilla::Range<const char16_t> input = inputChars.twoByteRange();
// Note: maximum case mapping length is three characters, so the result
// length might be > INT32_MAX. ICU will fail in this case.
static_assert(JSString::MAX_LENGTH <= INT32_MAX,
"String length must fit in int32_t for ICU");
static const size_t INLINE_CAPACITY = js::intl::INITIAL_CHAR_BUFFER_SIZE;
intl::FormatBuffer<char16_t, INLINE_CAPACITY> buffer(cx);
auto ok = mozilla::intl::String::ToLocaleUpperCase(locale, input, buffer);
if (ok.isErr()) {
intl::ReportInternalError(cx, ok.unwrapErr());
return false;
}
JSString* result = buffer.toString(cx);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#else
// When the Intl API is not exposed, String.prototype.toUpperCase is implemented
// in C++.
static bool str_toLocaleUpperCase(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype",
"toLocaleUpperCase");
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(
cx, ToStringForStringFunction(cx, "toLocaleUpperCase", args.thisv()));
if (!str) {
return false;
}
/*
* Forcefully ignore the first (or any) argument and return toUpperCase(),
* ECMA has reserved that argument, presumably for defining the locale.
*/
if (cx->runtime()->localeCallbacks &&
cx->runtime()->localeCallbacks->localeToUpperCase) {
RootedValue result(cx);
if (!cx->runtime()->localeCallbacks->localeToUpperCase(cx, str, &result)) {
return false;
}
args.rval().set(result);
return true;
}
Rooted<JSLinearString*> linear(cx, str->ensureLinear(cx));
if (!linear) {
return false;
}
JSString* result = StringToUpperCase(cx, linear);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
#endif // JS_HAS_INTL_API
#if JS_HAS_INTL_API
// String.prototype.localeCompare is self-hosted when Intl functionality is
// exposed, and the only intrinsics it requires are provided in the
// implementation of Intl.Collator.
#else
// String.prototype.localeCompare is implemented in C++ (delegating to
// JSLocaleCallbacks) when Intl functionality is not exposed.
static bool str_localeCompare(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype",
"localeCompare");
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(
cx, ToStringForStringFunction(cx, "localeCompare", args.thisv()));
if (!str) {
return false;
}
RootedString thatStr(cx, ToString<CanGC>(cx, args.get(0)));
if (!thatStr) {
return false;
}
if (cx->runtime()->localeCallbacks &&
cx->runtime()->localeCallbacks->localeCompare) {
RootedValue result(cx);
if (!cx->runtime()->localeCallbacks->localeCompare(cx, str, thatStr,
&result)) {
return false;
}
args.rval().set(result);
return true;
}
int32_t result;
if (!CompareStrings(cx, str, thatStr, &result)) {
return false;
}
args.rval().setInt32(result);
return true;
}
#endif // JS_HAS_INTL_API
#if JS_HAS_INTL_API
// ES2017 draft rev 45e890512fd77add72cc0ee742785f9f6f6482de
// 21.1.3.12 String.prototype.normalize ( [ form ] )
//
// String.prototype.normalize is only implementable if ICU's normalization
// functionality is available.
static bool str_normalize(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "normalize");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx,
ToStringForStringFunction(cx, "normalize", args.thisv()));
if (!str) {
return false;
}
using NormalizationForm = mozilla::intl::String::NormalizationForm;
NormalizationForm form;
if (!args.hasDefined(0)) {
// Step 3.
form = NormalizationForm::NFC;
} else {
// Step 4.
JSLinearString* formStr = ArgToLinearString(cx, args, 0);
if (!formStr) {
return false;
}
// Step 5.
if (EqualStrings(formStr, cx->names().NFC)) {
form = NormalizationForm::NFC;
} else if (EqualStrings(formStr, cx->names().NFD)) {
form = NormalizationForm::NFD;
} else if (EqualStrings(formStr, cx->names().NFKC)) {
form = NormalizationForm::NFKC;
} else if (EqualStrings(formStr, cx->names().NFKD)) {
form = NormalizationForm::NFKD;
} else {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_INVALID_NORMALIZE_FORM);
return false;
}
}
// Latin-1 strings are already in Normalization Form C.
if (form == NormalizationForm::NFC && str->hasLatin1Chars()) {
// Step 7.
args.rval().setString(str);
return true;
}
// Step 6.
AutoStableStringChars stableChars(cx);
if (!stableChars.initTwoByte(cx, str)) {
return false;
}
mozilla::Range<const char16_t> srcChars = stableChars.twoByteRange();
static const size_t INLINE_CAPACITY = js::intl::INITIAL_CHAR_BUFFER_SIZE;
intl::FormatBuffer<char16_t, INLINE_CAPACITY> buffer(cx);
auto alreadyNormalized =
mozilla::intl::String::Normalize(form, srcChars, buffer);
if (alreadyNormalized.isErr()) {
intl::ReportInternalError(cx, alreadyNormalized.unwrapErr());
return false;
}
using AlreadyNormalized = mozilla::intl::String::AlreadyNormalized;
// Return if the input string is already normalized.
if (alreadyNormalized.unwrap() == AlreadyNormalized::Yes) {
// Step 7.
args.rval().setString(str);
return true;
}
JSString* ns = buffer.toString(cx);
if (!ns) {
return false;
}
// Step 7.
args.rval().setString(ns);
return true;
}
#endif // JS_HAS_INTL_API
/**
* IsStringWellFormedUnicode ( string )
*/
static bool IsStringWellFormedUnicode(JSContext* cx, HandleString str,
size_t* isWellFormedUpTo) {
MOZ_ASSERT(isWellFormedUpTo);
*isWellFormedUpTo = 0;
size_t len = str->length();
// Latin1 chars are well-formed.
if (str->hasLatin1Chars()) {
*isWellFormedUpTo = len;
return true;
}
JSLinearString* linear = str->ensureLinear(cx);
if (!linear) {
return false;
}
{
AutoCheckCannotGC nogc;
*isWellFormedUpTo = Utf16ValidUpTo(Span{linear->twoByteChars(nogc), len});
}
return true;
}
/**
* Well-Formed Unicode Strings (Stage 3 proposal)
*
* String.prototype.isWellFormed
*/
static bool str_isWellFormed(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "isWellFormed");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1. Let O be ? RequireObjectCoercible(this value).
// Step 2. Let S be ? ToString(O).
RootedString str(cx,
ToStringForStringFunction(cx, "isWellFormed", args.thisv()));
if (!str) {
return false;
}
// Step 3. Return IsStringWellFormedUnicode(S).
size_t isWellFormedUpTo;
if (!IsStringWellFormedUnicode(cx, str, &isWellFormedUpTo)) {
return false;
}
MOZ_ASSERT(isWellFormedUpTo <= str->length());
args.rval().setBoolean(isWellFormedUpTo == str->length());
return true;
}
/**
* Well-Formed Unicode Strings (Stage 3 proposal)
*
* String.prototype.toWellFormed
*/
static bool str_toWellFormed(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "toWellFormed");
CallArgs args = CallArgsFromVp(argc, vp);
// Step 1. Let O be ? RequireObjectCoercible(this value).
// Step 2. Let S be ? ToString(O).
RootedString str(cx,
ToStringForStringFunction(cx, "toWellFormed", args.thisv()));
if (!str) {
return false;
}
// Step 3. Let strLen be the length of S.
size_t len = str->length();
// If the string itself is well-formed, return it.
size_t isWellFormedUpTo;
if (!IsStringWellFormedUnicode(cx, str, &isWellFormedUpTo)) {
return false;
}
if (isWellFormedUpTo == len) {
args.rval().setString(str);
return true;
}
MOZ_ASSERT(isWellFormedUpTo < len);
// Step 4-6
InlineCharBuffer<char16_t> buffer;
if (!buffer.maybeAlloc(cx, len)) {
return false;
}
{
AutoCheckCannotGC nogc;
JSLinearString* linear = str->ensureLinear(cx);
MOZ_ASSERT(linear, "IsStringWellFormedUnicode linearized the string");
PodCopy(buffer.get(), linear->twoByteChars(nogc), len);
auto span = mozilla::Span{buffer.get(), len};
// Replace the character.
span[isWellFormedUpTo] = unicode::REPLACEMENT_CHARACTER;
// Check any remaining characters.
auto remaining = span.From(isWellFormedUpTo + 1);
if (!remaining.IsEmpty()) {
EnsureUtf16ValiditySpan(remaining);
}
}
JSString* result = buffer.toStringDontDeflate(cx, len);
if (!result) {
return false;
}
// Step 7. Return result.
args.rval().setString(result);
return true;
}
static const JSFunctionSpec wellFormed_functions[] = {
JS_FN("isWellFormed", str_isWellFormed, 0, 0),
JS_FN("toWellFormed", str_toWellFormed, 0, 0),
JS_FS_END,
};
static MOZ_ALWAYS_INLINE bool ToStringIndex(JSContext* cx, Handle<Value> value,
size_t length,
mozilla::Maybe<size_t>* result) {
// Handle the common case of int32 indices first.
if (MOZ_LIKELY(value.isInt32())) {
size_t index = size_t(value.toInt32());
if (index < length) {
*result = mozilla::Some(index);
}
return true;
}
double index = 0.0;
if (!ToInteger(cx, value, &index)) {
return false;
}
if (0 <= index && index < length) {
*result = mozilla::Some(size_t(index));
}
return true;
}
static MOZ_ALWAYS_INLINE bool ToRelativeStringIndex(
JSContext* cx, Handle<Value> value, size_t length,
mozilla::Maybe<size_t>* result) {
// Handle the common case of int32 indices first.
if (MOZ_LIKELY(value.isInt32())) {
int32_t index = value.toInt32();
if (index < 0) {
index += int32_t(length);
}
if (size_t(index) < length) {
*result = mozilla::Some(size_t(index));
}
return true;
}
double index = 0.0;
if (!ToInteger(cx, value, &index)) {
return false;
}
if (index < 0) {
index += length;
}
if (0 <= index && index < length) {
*result = mozilla::Some(size_t(index));
}
return true;
}
/**
* 22.1.3.2 String.prototype.charAt ( pos )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
static bool str_charAt(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "charAt");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx, ToStringForStringFunction(cx, "charAt", args.thisv()));
if (!str) {
return false;
}
// Step 3.
mozilla::Maybe<size_t> index{};
if (!ToStringIndex(cx, args.get(0), str->length(), &index)) {
return false;
}
// Steps 4-5.
if (index.isNothing()) {
args.rval().setString(cx->runtime()->emptyString);
return true;
}
MOZ_ASSERT(*index < str->length());
// Step 6.
auto* result = cx->staticStrings().getUnitStringForElement(cx, str, *index);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
/**
* 22.1.3.3 String.prototype.charCodeAt ( pos )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
bool js::str_charCodeAt(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "charCodeAt");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx,
ToStringForStringFunction(cx, "charCodeAt", args.thisv()));
if (!str) {
return false;
}
// Step 3.
mozilla::Maybe<size_t> index{};
if (!ToStringIndex(cx, args.get(0), str->length(), &index)) {
return false;
}
// Steps 4-5.
if (index.isNothing()) {
args.rval().setNaN();
return true;
}
MOZ_ASSERT(*index < str->length());
// Step 6.
char16_t c;
if (!str->getChar(cx, *index, &c)) {
return false;
}
args.rval().setInt32(c);
return true;
}
/**
* 22.1.3.4 String.prototype.codePointAt ( pos )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
bool js::str_codePointAt(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "codePointAt");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx,
ToStringForStringFunction(cx, "codePointAt", args.thisv()));
if (!str) {
return false;
}
// Step 3.
mozilla::Maybe<size_t> index{};
if (!ToStringIndex(cx, args.get(0), str->length(), &index)) {
return false;
}
// Steps 4-5.
if (index.isNothing()) {
args.rval().setUndefined();
return true;
}
MOZ_ASSERT(*index < str->length());
// Step 6.
char32_t codePoint;
if (!str->getCodePoint(cx, *index, &codePoint)) {
return false;
}
// Step 7.
args.rval().setInt32(codePoint);
return true;
}
/**
* 22.1.3.1 String.prototype.at ( index )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
static bool str_at(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "at");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx, ToStringForStringFunction(cx, "at", args.thisv()));
if (!str) {
return false;
}
// Steps 3-6.
mozilla::Maybe<size_t> index{};
if (!ToRelativeStringIndex(cx, args.get(0), str->length(), &index)) {
return false;
}
// Step 7.
if (index.isNothing()) {
args.rval().setUndefined();
return true;
}
MOZ_ASSERT(*index < str->length());
// Step 8.
auto* result = cx->staticStrings().getUnitStringForElement(cx, str, *index);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
/*
* Boyer-Moore-Horspool superlinear search for pat:patlen in text:textlen.
* The patlen argument must be positive and no greater than sBMHPatLenMax.
*
* Return the index of pat in text, or -1 if not found.
*/
static const uint32_t sBMHCharSetSize = 256; /* ISO-Latin-1 */
static const uint32_t sBMHPatLenMax = 255; /* skip table element is uint8_t */
static const int sBMHBadPattern =
-2; /* return value if pat is not ISO-Latin-1 */
template <typename TextChar, typename PatChar>
static int BoyerMooreHorspool(const TextChar* text, uint32_t textLen,
const PatChar* pat, uint32_t patLen) {
MOZ_ASSERT(0 < patLen && patLen <= sBMHPatLenMax);
uint8_t skip[sBMHCharSetSize];
for (uint32_t i = 0; i < sBMHCharSetSize; i++) {
skip[i] = uint8_t(patLen);
}
uint32_t patLast = patLen - 1;
for (uint32_t i = 0; i < patLast; i++) {
char16_t c = pat[i];
if (c >= sBMHCharSetSize) {
return sBMHBadPattern;
}
skip[c] = uint8_t(patLast - i);
}
for (uint32_t k = patLast; k < textLen;) {
for (uint32_t i = k, j = patLast;; i--, j--) {
if (text[i] != pat[j]) {
break;
}
if (j == 0) {
return static_cast<int>(i); /* safe: max string size */
}
}
char16_t c = text[k];
k += (c >= sBMHCharSetSize) ? patLen : skip[c];
}
return -1;
}
template <typename TextChar, typename PatChar>
struct MemCmp {
using Extent = uint32_t;
static MOZ_ALWAYS_INLINE Extent computeExtent(const PatChar*,
uint32_t patLen) {
return (patLen - 2) * sizeof(PatChar);
}
static MOZ_ALWAYS_INLINE bool match(const PatChar* p, const TextChar* t,
Extent extent) {
MOZ_ASSERT(sizeof(TextChar) == sizeof(PatChar));
return memcmp(p, t, extent) == 0;
}
};
template <typename TextChar, typename PatChar>
struct ManualCmp {
using Extent = const PatChar*;
static MOZ_ALWAYS_INLINE Extent computeExtent(const PatChar* pat,
uint32_t patLen) {
return pat + patLen;
}
static MOZ_ALWAYS_INLINE bool match(const PatChar* p, const TextChar* t,
Extent extent) {
for (; p != extent; ++p, ++t) {
if (*p != *t) {
return false;
}
}
return true;
}
};
template <class InnerMatch, typename TextChar, typename PatChar>
static int Matcher(const TextChar* text, uint32_t textlen, const PatChar* pat,
uint32_t patlen) {
MOZ_ASSERT(patlen > 1);
const typename InnerMatch::Extent extent =
InnerMatch::computeExtent(pat, patlen);
uint32_t i = 0;
uint32_t n = textlen - patlen + 1;
while (i < n) {
const TextChar* pos;
// This is a bit awkward. Consider the case where we're searching "abcdef"
// for "def". n will be 4, because we know in advance that the last place we
// can *start* a successful search will be at 'd'. However, if we just use n
// - i, then our first search will be looking through "abcd" for "de",
// because our memchr2xN functions search for two characters at a time. So
// we just have to compensate by adding 1. This will never exceed textlen
// because we know patlen is at least two.
size_t searchLen = n - i + 1;
if (sizeof(TextChar) == 1) {
MOZ_ASSERT(pat[0] <= 0xff);
pos = (TextChar*)SIMD::memchr2x8((char*)text + i, pat[0], pat[1],
searchLen);
} else {
pos = (TextChar*)SIMD::memchr2x16((char16_t*)(text + i), char16_t(pat[0]),
char16_t(pat[1]), searchLen);
}
if (pos == nullptr) {
return -1;
}
i = static_cast<uint32_t>(pos - text);
const uint32_t inlineLookaheadChars = 2;
if (InnerMatch::match(pat + inlineLookaheadChars,
text + i + inlineLookaheadChars, extent)) {
return i;
}
i += 1;
}
return -1;
}
template <typename TextChar, typename PatChar>
static MOZ_ALWAYS_INLINE int StringMatch(const TextChar* text, uint32_t textLen,
const PatChar* pat, uint32_t patLen) {
if (patLen == 0) {
return 0;
}
if (textLen < patLen) {
return -1;
}
if (sizeof(TextChar) == 1 && sizeof(PatChar) > 1 && pat[0] > 0xff) {
return -1;
}
if (patLen == 1) {
const TextChar* pos;
if (sizeof(TextChar) == 1) {
MOZ_ASSERT(pat[0] <= 0xff);
pos = (TextChar*)SIMD::memchr8((char*)text, pat[0], textLen);
} else {
pos =
(TextChar*)SIMD::memchr16((char16_t*)text, char16_t(pat[0]), textLen);
}
if (pos == nullptr) {
return -1;
}
return pos - text;
}
// We use a fast two-character-wide search in Matcher below, so we need to
// validate that pat[1] isn't outside the latin1 range up front if the
// sizes are different.
if (sizeof(TextChar) == 1 && sizeof(PatChar) > 1 && pat[1] > 0xff) {
return -1;
}
/*
* If the text or pattern string is short, BMH will be more expensive than
* the basic linear scan due to initialization cost and a more complex loop
* body. While the correct threshold is input-dependent, we can make a few
* conservative observations:
* - When |textLen| is "big enough", the initialization time will be
* proportionally small, so the worst-case slowdown is minimized.
* - When |patLen| is "too small", even the best case for BMH will be
* slower than a simple scan for large |textLen| due to the more complex
* loop body of BMH.
* From this, the values for "big enough" and "too small" are determined
*/
if (textLen >= 512 && patLen >= 11 && patLen <= sBMHPatLenMax) {
int index = BoyerMooreHorspool(text, textLen, pat, patLen);
if (index != sBMHBadPattern) {
return index;
}
}
/*
* For big patterns with large potential overlap we want the SIMD-optimized
* speed of memcmp. For small patterns, a simple loop is faster. We also can't
* use memcmp if one of the strings is TwoByte and the other is Latin-1.
*/
return (patLen > 128 && std::is_same_v<TextChar, PatChar>)
? Matcher<MemCmp<TextChar, PatChar>, TextChar, PatChar>(
text, textLen, pat, patLen)
: Matcher<ManualCmp<TextChar, PatChar>, TextChar, PatChar>(
text, textLen, pat, patLen);
}
static int32_t StringMatch(JSLinearString* text, JSLinearString* pat,
uint32_t start = 0) {
MOZ_ASSERT(start <= text->length());
uint32_t textLen = text->length() - start;
uint32_t patLen = pat->length();
int match;
AutoCheckCannotGC nogc;
if (text->hasLatin1Chars()) {
const Latin1Char* textChars = text->latin1Chars(nogc) + start;
if (pat->hasLatin1Chars()) {
match = StringMatch(textChars, textLen, pat->latin1Chars(nogc), patLen);
} else {
match = StringMatch(textChars, textLen, pat->twoByteChars(nogc), patLen);
}
} else {
const char16_t* textChars = text->twoByteChars(nogc) + start;
if (pat->hasLatin1Chars()) {
match = StringMatch(textChars, textLen, pat->latin1Chars(nogc), patLen);
} else {
match = StringMatch(textChars, textLen, pat->twoByteChars(nogc), patLen);
}
}
return (match == -1) ? -1 : start + match;
}
static const size_t sRopeMatchThresholdRatioLog2 = 4;
int js::StringFindPattern(JSLinearString* text, JSLinearString* pat,
size_t start) {
return StringMatch(text, pat, start);
}
typedef Vector<JSLinearString*, 16, SystemAllocPolicy> LinearStringVector;
template <typename TextChar, typename PatChar>
static int RopeMatchImpl(const AutoCheckCannotGC& nogc,
LinearStringVector& strings, const PatChar* pat,
size_t patLen) {
/* Absolute offset from the beginning of the logical text string. */
int pos = 0;
for (JSLinearString** outerp = strings.begin(); outerp != strings.end();
++outerp) {
/* Try to find a match within 'outer'. */
JSLinearString* outer = *outerp;
const TextChar* chars = outer->chars<TextChar>(nogc);
size_t len = outer->length();
int matchResult = StringMatch(chars, len, pat, patLen);
if (matchResult != -1) {
/* Matched! */
return pos + matchResult;
}
/* Try to find a match starting in 'outer' and running into other nodes. */
const TextChar* const text = chars + (patLen > len ? 0 : len - patLen + 1);
const TextChar* const textend = chars + len;
const PatChar p0 = *pat;
const PatChar* const p1 = pat + 1;
const PatChar* const patend = pat + patLen;
for (const TextChar* t = text; t != textend;) {
if (*t++ != p0) {
continue;
}
JSLinearString** innerp = outerp;
const TextChar* ttend = textend;
const TextChar* tt = t;
for (const PatChar* pp = p1; pp != patend; ++pp, ++tt) {
while (tt == ttend) {
if (++innerp == strings.end()) {
return -1;
}
JSLinearString* inner = *innerp;
tt = inner->chars<TextChar>(nogc);
ttend = tt + inner->length();
}
if (*pp != *tt) {
goto break_continue;
}
}
/* Matched! */
return pos + (t - chars) - 1; /* -1 because of *t++ above */
break_continue:;
}
pos += len;
}
return -1;
}
/*
* RopeMatch takes the text to search and the pattern to search for in the text.
* RopeMatch returns false on OOM and otherwise returns the match index through
* the 'match' outparam (-1 for not found).
*/
static bool RopeMatch(JSContext* cx, JSRope* text, JSLinearString* pat,
int* match) {
uint32_t patLen = pat->length();
if (patLen == 0) {
*match = 0;
return true;
}
if (text->length() < patLen) {
*match = -1;
return true;
}
/*
* List of leaf nodes in the rope. If we run out of memory when trying to
* append to this list, we can still fall back to StringMatch, so use the
* system allocator so we don't report OOM in that case.
*/
LinearStringVector strings;
/*
* We don't want to do rope matching if there is a poor node-to-char ratio,
* since this means spending a lot of time in the match loop below. We also
* need to build the list of leaf nodes. Do both here: iterate over the
* nodes so long as there are not too many.
*
* We also don't use rope matching if the rope contains both Latin-1 and
* TwoByte nodes, to simplify the match algorithm.
*/
{
size_t threshold = text->length() >> sRopeMatchThresholdRatioLog2;
StringSegmentRange r(cx);
if (!r.init(text)) {
return false;
}
bool textIsLatin1 = text->hasLatin1Chars();
while (!r.empty()) {
if (threshold-- == 0 || r.front()->hasLatin1Chars() != textIsLatin1 ||
!strings.append(r.front())) {
JSLinearString* linear = text->ensureLinear(cx);
if (!linear) {
return false;
}
*match = StringMatch(linear, pat);
return true;
}
if (!r.popFront()) {
return false;
}
}
}
AutoCheckCannotGC nogc;
if (text->hasLatin1Chars()) {
if (pat->hasLatin1Chars()) {
*match = RopeMatchImpl<Latin1Char>(nogc, strings, pat->latin1Chars(nogc),
patLen);
} else {
*match = RopeMatchImpl<Latin1Char>(nogc, strings, pat->twoByteChars(nogc),
patLen);
}
} else {
if (pat->hasLatin1Chars()) {
*match = RopeMatchImpl<char16_t>(nogc, strings, pat->latin1Chars(nogc),
patLen);
} else {
*match = RopeMatchImpl<char16_t>(nogc, strings, pat->twoByteChars(nogc),
patLen);
}
}
return true;
}
static MOZ_ALWAYS_INLINE bool ReportErrorIfFirstArgIsRegExp(
JSContext* cx, const CallArgs& args) {
// Only call IsRegExp if the first argument is definitely an object, so we
// don't pay the cost of an additional function call in the common case.
if (args.length() == 0 || !args[0].isObject()) {
return true;
}
bool isRegExp;
if (!IsRegExp(cx, args[0], &isRegExp)) {
return false;
}
if (isRegExp) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_INVALID_ARG_TYPE, "first", "",
"Regular Expression");
return false;
}
return true;
}
// ES2018 draft rev de77aaeffce115deaf948ed30c7dbe4c60983c0c
// 21.1.3.7 String.prototype.includes ( searchString [ , position ] )
bool js::str_includes(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "includes");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx, ToStringForStringFunction(cx, "includes", args.thisv()));
if (!str) {
return false;
}
// Steps 3-4.
if (!ReportErrorIfFirstArgIsRegExp(cx, args)) {
return false;
}
// Step 5.
Rooted<JSLinearString*> searchStr(cx, ArgToLinearString(cx, args, 0));
if (!searchStr) {
return false;
}
// Step 6.
uint32_t pos = 0;
if (args.hasDefined(1)) {
if (args[1].isInt32()) {
int i = args[1].toInt32();
pos = (i < 0) ? 0U : uint32_t(i);
} else {
double d;
if (!ToInteger(cx, args[1], &d)) {
return false;
}
pos = uint32_t(std::min(std::max(d, 0.0), double(UINT32_MAX)));
}
}
// Step 7.
uint32_t textLen = str->length();
// Step 8.
uint32_t start = std::min(pos, textLen);
// Steps 9-10.
JSLinearString* text = str->ensureLinear(cx);
if (!text) {
return false;
}
args.rval().setBoolean(StringMatch(text, searchStr, start) != -1);
return true;
}
bool js::StringIncludes(JSContext* cx, HandleString string,
HandleString searchString, bool* result) {
JSLinearString* text = string->ensureLinear(cx);
if (!text) {
return false;
}
JSLinearString* searchStr = searchString->ensureLinear(cx);
if (!searchStr) {
return false;
}
*result = StringMatch(text, searchStr, 0) != -1;
return true;
}
/* ES6 20120927 draft 15.5.4.7. */
bool js::str_indexOf(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "indexOf");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1, 2, and 3
RootedString str(cx, ToStringForStringFunction(cx, "indexOf", args.thisv()));
if (!str) {
return false;
}
// Steps 4 and 5
Rooted<JSLinearString*> searchStr(cx, ArgToLinearString(cx, args, 0));
if (!searchStr) {
return false;
}
// Steps 6 and 7
uint32_t pos = 0;
if (args.hasDefined(1)) {
if (args[1].isInt32()) {
int i = args[1].toInt32();
pos = (i < 0) ? 0U : uint32_t(i);
} else {
double d;
if (!ToInteger(cx, args[1], &d)) {
return false;
}
pos = uint32_t(std::min(std::max(d, 0.0), double(UINT32_MAX)));
}
}
// Step 8
uint32_t textLen = str->length();
// Step 9
uint32_t start = std::min(pos, textLen);
if (str == searchStr) {
// AngularJS often invokes "false".indexOf("false"). This check should
// be cheap enough to not hurt anything else.
args.rval().setInt32(start == 0 ? 0 : -1);
return true;
}
// Steps 10 and 11
JSLinearString* text = str->ensureLinear(cx);
if (!text) {
return false;
}
args.rval().setInt32(StringMatch(text, searchStr, start));
return true;
}
bool js::StringIndexOf(JSContext* cx, HandleString string,
HandleString searchString, int32_t* result) {
if (string == searchString) {
*result = 0;
return true;
}
JSLinearString* text = string->ensureLinear(cx);
if (!text) {
return false;
}
JSLinearString* searchStr = searchString->ensureLinear(cx);
if (!searchStr) {
return false;
}
*result = StringMatch(text, searchStr, 0);
return true;
}
template <typename TextChar, typename PatChar>
static int32_t LastIndexOfImpl(const TextChar* text, size_t textLen,
const PatChar* pat, size_t patLen,
size_t start) {
MOZ_ASSERT(patLen > 0);
MOZ_ASSERT(patLen <= textLen);
MOZ_ASSERT(start <= textLen - patLen);
const PatChar p0 = *pat;
const PatChar* patNext = pat + 1;
const PatChar* patEnd = pat + patLen;
for (const TextChar* t = text + start; t >= text; --t) {
if (*t == p0) {
const TextChar* t1 = t + 1;
for (const PatChar* p1 = patNext; p1 < patEnd; ++p1, ++t1) {
if (*t1 != *p1) {
goto break_continue;
}
}
return static_cast<int32_t>(t - text);
}
break_continue:;
}
return -1;
}
static int32_t LastIndexOf(JSLinearString* text, JSLinearString* searchStr,
size_t start) {
AutoCheckCannotGC nogc;
size_t len = text->length();
size_t searchLen = searchStr->length();
if (text->hasLatin1Chars()) {
const Latin1Char* textChars = text->latin1Chars(nogc);
if (searchStr->hasLatin1Chars()) {
return LastIndexOfImpl(textChars, len, searchStr->latin1Chars(nogc),
searchLen, start);
}
return LastIndexOfImpl(textChars, len, searchStr->twoByteChars(nogc),
searchLen, start);
}
const char16_t* textChars = text->twoByteChars(nogc);
if (searchStr->hasLatin1Chars()) {
return LastIndexOfImpl(textChars, len, searchStr->latin1Chars(nogc),
searchLen, start);
}
return LastIndexOfImpl(textChars, len, searchStr->twoByteChars(nogc),
searchLen, start);
}
// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
// 21.1.3.9 String.prototype.lastIndexOf ( searchString [ , position ] )
static bool str_lastIndexOf(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "lastIndexOf");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx,
ToStringForStringFunction(cx, "lastIndexOf", args.thisv()));
if (!str) {
return false;
}
// Step 3.
Rooted<JSLinearString*> searchStr(cx, ArgToLinearString(cx, args, 0));
if (!searchStr) {
return false;
}
// Step 6.
size_t len = str->length();
// Step 8.
size_t searchLen = searchStr->length();
// Steps 4-5, 7.
int start = len - searchLen; // Start searching here
if (args.hasDefined(1)) {
if (args[1].isInt32()) {
int i = args[1].toInt32();
if (i <= 0) {
start = 0;
} else if (i < start) {
start = i;
}
} else {
double d;
if (!ToNumber(cx, args[1], &d)) {
return false;
}
if (!std::isnan(d)) {
d = JS::ToInteger(d);
if (d <= 0) {
start = 0;
} else if (d < start) {
start = int(d);
}
}
}
}
if (str == searchStr) {
args.rval().setInt32(0);
return true;
}
if (searchLen > len) {
args.rval().setInt32(-1);
return true;
}
if (searchLen == 0) {
args.rval().setInt32(start);
return true;
}
MOZ_ASSERT(0 <= start && size_t(start) < len);
JSLinearString* text = str->ensureLinear(cx);
if (!text) {
return false;
}
// Step 9.
args.rval().setInt32(LastIndexOf(text, searchStr, start));
return true;
}
bool js::StringLastIndexOf(JSContext* cx, HandleString string,
HandleString searchString, int32_t* result) {
if (string == searchString) {
*result = 0;
return true;
}
size_t len = string->length();
size_t searchLen = searchString->length();
if (searchLen > len) {
*result = -1;
return true;
}
MOZ_ASSERT(len >= searchLen);
size_t start = len - searchLen;
if (searchLen == 0) {
*result = start;
return true;
}
MOZ_ASSERT(start < len);
JSLinearString* text = string->ensureLinear(cx);
if (!text) {
return false;
}
JSLinearString* searchStr = searchString->ensureLinear(cx);
if (!searchStr) {
return false;
}
*result = LastIndexOf(text, searchStr, start);
return true;
}
// ES2018 draft rev de77aaeffce115deaf948ed30c7dbe4c60983c0c
// 21.1.3.20 String.prototype.startsWith ( searchString [ , position ] )
bool js::str_startsWith(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "startsWith");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx,
ToStringForStringFunction(cx, "startsWith", args.thisv()));
if (!str) {
return false;
}
// Steps 3-4.
if (!ReportErrorIfFirstArgIsRegExp(cx, args)) {
return false;
}
// Step 5.
Rooted<JSLinearString*> searchStr(cx, ArgToLinearString(cx, args, 0));
if (!searchStr) {
return false;
}
// Step 6.
uint32_t pos = 0;
if (args.hasDefined(1)) {
if (args[1].isInt32()) {
int i = args[1].toInt32();
pos = (i < 0) ? 0U : uint32_t(i);
} else {
double d;
if (!ToInteger(cx, args[1], &d)) {
return false;
}
pos = uint32_t(std::min(std::max(d, 0.0), double(UINT32_MAX)));
}
}
// Step 7.
uint32_t textLen = str->length();
// Step 8.
uint32_t start = std::min(pos, textLen);
// Step 9.
uint32_t searchLen = searchStr->length();
// Step 10.
if (searchLen + start < searchLen || searchLen + start > textLen) {
args.rval().setBoolean(false);
return true;
}
// Steps 11-12.
JSLinearString* text = str->ensureLinear(cx);
if (!text) {
return false;
}
args.rval().setBoolean(HasSubstringAt(text, searchStr, start));
return true;
}
bool js::StringStartsWith(JSContext* cx, HandleString string,
HandleString searchString, bool* result) {
if (searchString->length() > string->length()) {
*result = false;
return true;
}
JSLinearString* str = string->ensureLinear(cx);
if (!str) {
return false;
}
JSLinearString* searchStr = searchString->ensureLinear(cx);
if (!searchStr) {
return false;
}
*result = HasSubstringAt(str, searchStr, 0);
return true;
}
// ES2018 draft rev de77aaeffce115deaf948ed30c7dbe4c60983c0c
// 21.1.3.6 String.prototype.endsWith ( searchString [ , endPosition ] )
bool js::str_endsWith(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "endsWith");
CallArgs args = CallArgsFromVp(argc, vp);
// Steps 1-2.
RootedString str(cx, ToStringForStringFunction(cx, "endsWith", args.thisv()));
if (!str) {
return false;
}
// Steps 3-4.
if (!ReportErrorIfFirstArgIsRegExp(cx, args)) {
return false;
}
// Step 5.
Rooted<JSLinearString*> searchStr(cx, ArgToLinearString(cx, args, 0));
if (!searchStr) {
return false;
}
// Step 6.
uint32_t textLen = str->length();
// Step 7.
uint32_t pos = textLen;
if (args.hasDefined(1)) {
if (args[1].isInt32()) {
int i = args[1].toInt32();
pos = (i < 0) ? 0U : uint32_t(i);
} else {
double d;
if (!ToInteger(cx, args[1], &d)) {
return false;
}
pos = uint32_t(std::min(std::max(d, 0.0), double(UINT32_MAX)));
}
}
// Step 8.
uint32_t end = std::min(pos, textLen);
// Step 9.
uint32_t searchLen = searchStr->length();
// Step 11 (reordered).
if (searchLen > end) {
args.rval().setBoolean(false);
return true;
}
// Step 10.
uint32_t start = end - searchLen;
// Steps 12-13.
JSLinearString* text = str->ensureLinear(cx);
if (!text) {
return false;
}
args.rval().setBoolean(HasSubstringAt(text, searchStr, start));
return true;
}
bool js::StringEndsWith(JSContext* cx, HandleString string,
HandleString searchString, bool* result) {
if (searchString->length() > string->length()) {
*result = false;
return true;
}
JSLinearString* str = string->ensureLinear(cx);
if (!str) {
return false;
}
JSLinearString* searchStr = searchString->ensureLinear(cx);
if (!searchStr) {
return false;
}
uint32_t start = str->length() - searchStr->length();
*result = HasSubstringAt(str, searchStr, start);
return true;
}
template <typename CharT>
static void TrimString(const CharT* chars, bool trimStart, bool trimEnd,
size_t length, size_t* pBegin, size_t* pEnd) {
size_t begin = 0, end = length;
if (trimStart) {
while (begin < length && unicode::IsSpace(chars[begin])) {
++begin;
}
}
if (trimEnd) {
while (end > begin && unicode::IsSpace(chars[end - 1])) {
--end;
}
}
*pBegin = begin;
*pEnd = end;
}
static JSLinearString* TrimString(JSContext* cx, JSString* str, bool trimStart,
bool trimEnd) {
JSLinearString* linear = str->ensureLinear(cx);
if (!linear) {
return nullptr;
}
size_t length = linear->length();
size_t begin, end;
if (linear->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
TrimString(linear->latin1Chars(nogc), trimStart, trimEnd, length, &begin,
&end);
} else {
AutoCheckCannotGC nogc;
TrimString(linear->twoByteChars(nogc), trimStart, trimEnd, length, &begin,
&end);
}
return NewDependentString(cx, linear, begin, end - begin);
}
JSString* js::StringTrim(JSContext* cx, HandleString string) {
return TrimString(cx, string, true, true);
}
JSString* js::StringTrimStart(JSContext* cx, HandleString string) {
return TrimString(cx, string, true, false);
}
JSString* js::StringTrimEnd(JSContext* cx, HandleString string) {
return TrimString(cx, string, false, true);
}
static bool TrimString(JSContext* cx, const CallArgs& args, const char* funName,
bool trimStart, bool trimEnd) {
JSString* str = ToStringForStringFunction(cx, funName, args.thisv());
if (!str) {
return false;
}
JSLinearString* result = TrimString(cx, str, trimStart, trimEnd);
if (!result) {
return false;
}
args.rval().setString(result);
return true;
}
static bool str_trim(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "trim");
CallArgs args = CallArgsFromVp(argc, vp);
return TrimString(cx, args, "trim", true, true);
}
static bool str_trimStart(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "trimStart");
CallArgs args = CallArgsFromVp(argc, vp);
return TrimString(cx, args, "trimStart", true, false);
}
static bool str_trimEnd(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "String.prototype", "trimEnd");
CallArgs args = CallArgsFromVp(argc, vp);
return TrimString(cx, args, "trimEnd", false, true);
}
// Utility for building a rope (lazy concatenation) of strings.
class RopeBuilder {
JSContext* cx;
RootedString res;
RopeBuilder(const RopeBuilder& other) = delete;
void operator=(const RopeBuilder& other) = delete;
public:
explicit RopeBuilder(JSContext* cx)
: cx(cx), res(cx, cx->runtime()->emptyString) {}
inline bool append(HandleString str) {
res = ConcatStrings<CanGC>(cx, res, str);
return !!res;
}
inline JSString* result() { return res; }
};
namespace {
template <typename CharT>
static uint32_t FindDollarIndex(const CharT* chars, size_t length) {
if (const CharT* p = js_strchr_limit(chars, '$', chars + length)) {
uint32_t dollarIndex = p - chars;
MOZ_ASSERT(dollarIndex < length);
return dollarIndex;
}
return UINT32_MAX;
}
} /* anonymous namespace */
/*
* Constructs a result string that looks like:
*
* newstring = string[:matchStart] + repstr + string[matchEnd:]
*/
static JSString* BuildFlatReplacement(JSContext* cx, HandleString textstr,
Handle<JSLinearString*> repstr,
size_t matchStart, size_t patternLength) {
size_t matchEnd = matchStart + patternLength;
RootedString resultStr(cx, NewDependentString(cx, textstr, 0, matchStart));
if (!resultStr) {
return nullptr;
}
resultStr = ConcatStrings<CanGC>(cx, resultStr, repstr);
if (!resultStr) {
return nullptr;
}
MOZ_ASSERT(textstr->length() >= matchEnd);
RootedString rest(cx, NewDependentString(cx, textstr, matchEnd,
textstr->length() - matchEnd));
if (!rest) {
return nullptr;
}
return ConcatStrings<CanGC>(cx, resultStr, rest);
}
static JSString* BuildFlatRopeReplacement(JSContext* cx, HandleString textstr,
Handle<JSLinearString*> repstr,
size_t match, size_t patternLength) {
MOZ_ASSERT(textstr->isRope());
size_t matchEnd = match + patternLength;
/*
* If we are replacing over a rope, avoid flattening it by iterating
* through it, building a new rope.
*/
StringSegmentRange r(cx);
if (!r.init(textstr)) {
return nullptr;
}
RopeBuilder builder(cx);
/*
* Special case when the pattern string is '', which matches to the
* head of the string and doesn't overlap with any component of the rope.
*/
if (patternLength == 0) {
MOZ_ASSERT(match == 0);
if (!builder.append(repstr)) {
return nullptr;
}
}
size_t pos = 0;
while (!r.empty()) {
RootedString str(cx, r.front());
size_t len = str->length();
size_t strEnd = pos + len;
if (pos < matchEnd && strEnd > match) {
/*
* We need to special-case any part of the rope that overlaps
* with the replacement string.
*/
if (match >= pos) {
/*
* If this part of the rope overlaps with the left side of
* the pattern, then it must be the only one to overlap with
* the first character in the pattern, so we include the
* replacement string here.
*/
RootedString leftSide(cx, NewDependentString(cx, str, 0, match - pos));
if (!leftSide || !builder.append(leftSide) || !builder.append(repstr)) {
return nullptr;
}
}
/*
* If str runs off the end of the matched string, append the
* last part of str.
*/
if (strEnd > matchEnd) {
RootedString rightSide(
cx, NewDependentString(cx, str, matchEnd - pos, strEnd - matchEnd));
if (!rightSide || !builder.append(rightSide)) {
return nullptr;
}
}
} else {
if (!builder.append(str)) {
return nullptr;
}
}
pos += str->length();
if (!r.popFront()) {
return nullptr;
}
}
return builder.result();
}
template <typename CharT>
static bool AppendDollarReplacement(StringBuffer& newReplaceChars,
size_t firstDollarIndex, size_t matchStart,
size_t matchLimit, JSLinearString* text,
const CharT* repChars, size_t repLength) {
MOZ_ASSERT(firstDollarIndex < repLength);
MOZ_ASSERT(matchStart <= matchLimit);
MOZ_ASSERT(matchLimit <= text->length());
// Move the pre-dollar chunk in bulk.
if (!newReplaceChars.append(repChars, firstDollarIndex)) {
return false;
}
// Move the rest char-by-char, interpreting dollars as we encounter them.
const CharT* repLimit = repChars + repLength;
for (const CharT* it = repChars + firstDollarIndex; it < repLimit; ++it) {
if (*it != '$' || it == repLimit - 1) {
if (!newReplaceChars.append(*it)) {
return false;
}
continue;
}
switch (*(it + 1)) {
case '$':
// Eat one of the dollars.
if (!newReplaceChars.append(*it)) {
return false;
}
break;
case '&':
if (!newReplaceChars.appendSubstring(text, matchStart,
matchLimit - matchStart)) {
return false;
}
break;
case '`':
if (!newReplaceChars.appendSubstring(text, 0, matchStart)) {
return false;
}
break;
case '\'':
if (!newReplaceChars.appendSubstring(text, matchLimit,
text->length() - matchLimit)) {
return false;
}
break;
default:
// The dollar we saw was not special (no matter what its mother told
// it).
if (!newReplaceChars.append(*it)) {
return false;
}
continue;
}
++it; // We always eat an extra char in the above switch.
}
return true;
}
/*
* Perform a linear-scan dollar substitution on the replacement text.
*/
static JSLinearString* InterpretDollarReplacement(
JSContext* cx, HandleString textstrArg, Handle<JSLinearString*> repstr,
uint32_t firstDollarIndex, size_t matchStart, size_t patternLength) {
Rooted<JSLinearString*> textstr(cx, textstrArg->ensureLinear(cx));
if (!textstr) {
return nullptr;
}
size_t matchLimit = matchStart + patternLength;
/*
* Most probably:
*
* len(newstr) >= len(orig) - len(match) + len(replacement)
*
* Note that dollar vars _could_ make the resulting text smaller than this.
*/
JSStringBuilder newReplaceChars(cx);
if (repstr->hasTwoByteChars() && !newReplaceChars.ensureTwoByteChars()) {
return nullptr;
}
if (!newReplaceChars.reserve(textstr->length() - patternLength +
repstr->length())) {
return nullptr;
}
bool res;
if (repstr->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
res = AppendDollarReplacement(newReplaceChars, firstDollarIndex, matchStart,
matchLimit, textstr,
repstr->latin1Chars(nogc), repstr->length());
} else {
AutoCheckCannotGC nogc;
res = AppendDollarReplacement(newReplaceChars, firstDollarIndex, matchStart,
matchLimit, textstr,
repstr->twoByteChars(nogc), repstr->length());
}
if (!res) {
return nullptr;
}
return newReplaceChars.finishString();
}
template <typename StrChar, typename RepChar>
static bool StrFlatReplaceGlobal(JSContext* cx, JSLinearString* str,
JSLinearString* pat, JSLinearString* rep,
StringBuffer& sb) {
MOZ_ASSERT(str->length() > 0);
AutoCheckCannotGC nogc;
const StrChar* strChars = str->chars<StrChar>(nogc);
const RepChar* repChars = rep->chars<RepChar>(nogc);
// The pattern is empty, so we interleave the replacement string in-between
// each character.
if (!pat->length()) {
CheckedInt<uint32_t> strLength(str->length());
CheckedInt<uint32_t> repLength(rep->length());
CheckedInt<uint32_t> length = repLength * (strLength - 1) + strLength;
if (!length.isValid()) {
ReportAllocationOverflow(cx);
return false;
}
if (!sb.reserve(length.value())) {
return false;
}
for (unsigned i = 0; i < str->length() - 1; ++i, ++strChars) {
sb.infallibleAppend(*strChars);
sb.infallibleAppend(repChars, rep->length());
}
sb.infallibleAppend(*strChars);
return true;
}
// If it's true, we are sure that the result's length is, at least, the same
// length as |str->length()|.
if (rep->length() >= pat->length()) {
if (!sb.reserve(str->length())) {
return false;
}
}
uint32_t start = 0;
for (;;) {
int match = StringMatch(str, pat, start);
if (match < 0) {
break;
}
if (!sb.append(strChars + start, match - start)) {
return false;
}
if (!sb.append(repChars, rep->length())) {
return false;
}
start = match + pat->length();
}
if (!sb.append(strChars + start, str->length() - start)) {
return false;
}
return true;
}
// This is identical to "str.split(pattern).join(replacement)" except that we
// do some deforestation optimization in Ion.
JSString* js::StringFlatReplaceString(JSContext* cx, HandleString string,
HandleString pattern,
HandleString replacement) {
MOZ_ASSERT(string);
MOZ_ASSERT(pattern);
MOZ_ASSERT(replacement);
if (!string->length()) {
return string;
}
Rooted<JSLinearString*> linearRepl(cx, replacement->ensureLinear(cx));
if (!linearRepl) {
return nullptr;
}
Rooted<JSLinearString*> linearPat(cx, pattern->ensureLinear(cx));
if (!linearPat) {
return nullptr;
}
Rooted<JSLinearString*> linearStr(cx, string->ensureLinear(cx));
if (!linearStr) {
return nullptr;
}
JSStringBuilder sb(cx);
if (linearStr->hasTwoByteChars()) {
if (!sb.ensureTwoByteChars()) {
return nullptr;
}
if (linearRepl->hasTwoByteChars()) {
if (!StrFlatReplaceGlobal<char16_t, char16_t>(cx, linearStr, linearPat,
linearRepl, sb)) {
return nullptr;
}
} else {
if (!StrFlatReplaceGlobal<char16_t, Latin1Char>(cx, linearStr, linearPat,
linearRepl, sb)) {
return nullptr;
}
}
} else {
if (linearRepl->hasTwoByteChars()) {
if (!sb.ensureTwoByteChars()) {
return nullptr;
}
if (!StrFlatReplaceGlobal<Latin1Char, char16_t>(cx, linearStr, linearPat,
linearRepl, sb)) {
return nullptr;
}
} else {
if (!StrFlatReplaceGlobal<Latin1Char, Latin1Char>(
cx, linearStr, linearPat, linearRepl, sb)) {
return nullptr;
}
}
}
return sb.finishString();
}
JSString* js::str_replace_string_raw(JSContext* cx, HandleString string,
HandleString pattern,
HandleString replacement) {
Rooted<JSLinearString*> pat(cx, pattern->ensureLinear(cx));
if (!pat) {
return nullptr;
}
/*
* |string| could be a rope, so we want to avoid flattening it for as
* long as possible.
*/
int32_t match;
if (string->isRope()) {
if (!RopeMatch(cx, &string->asRope(), pat, &match)) {
return nullptr;
}
} else {
match = StringMatch(&string->asLinear(), pat, 0);
}
if (match < 0) {
return string;
}
Rooted<JSLinearString*> repl(cx, replacement->ensureLinear(cx));
if (!repl) {
return nullptr;
}
uint32_t dollarIndex;
{
AutoCheckCannotGC nogc;
dollarIndex =
repl->hasLatin1Chars()
? FindDollarIndex(repl->latin1Chars(nogc), repl->length())
: FindDollarIndex(repl->twoByteChars(nogc), repl->length());
}
size_t patternLength = pat->length();
if (dollarIndex != UINT32_MAX) {
repl = InterpretDollarReplacement(cx, string, repl, dollarIndex, match,
patternLength);
if (!repl) {
return nullptr;
}
} else if (string->isRope()) {
return BuildFlatRopeReplacement(cx, string, repl, match, patternLength);
}
return BuildFlatReplacement(cx, string, repl, match, patternLength);
}
template <typename StrChar, typename RepChar>
static bool ReplaceAllInternal(const AutoCheckCannotGC& nogc,
JSLinearString* string,
JSLinearString* searchString,
JSLinearString* replaceString,
const int32_t startPosition,
JSStringBuilder& result) {
// Step 7.
const size_t stringLength = string->length();
const size_t searchLength = searchString->length();
const size_t replaceLength = replaceString->length();
MOZ_ASSERT(stringLength > 0);
MOZ_ASSERT(searchLength > 0);
MOZ_ASSERT(stringLength >= searchLength);
// Step 12.
uint32_t endOfLastMatch = 0;
const StrChar* strChars = string->chars<StrChar>(nogc);
const RepChar* repChars = replaceString->chars<RepChar>(nogc);
uint32_t dollarIndex = FindDollarIndex(repChars, replaceLength);
// If it's true, we are sure that the result's length is, at least, the same
// length as |str->length()|.
if (replaceLength >= searchLength) {
if (!result.reserve(stringLength)) {
return false;
}
}
int32_t position = startPosition;
do {
// Step 14.c.
// Append the substring before the current match.
if (!result.append(strChars + endOfLastMatch, position - endOfLastMatch)) {
return false;
}
// Steps 14.a-b and 14.d.
// Append the replacement.
if (dollarIndex != UINT32_MAX) {
size_t matchLimit = position + searchLength;
if (!AppendDollarReplacement(result, dollarIndex, position, matchLimit,
string, repChars, replaceLength)) {
return false;
}
} else {
if (!result.append(repChars, replaceLength)) {
return false;
}
}
// Step 14.e.
endOfLastMatch = position + searchLength;
// Step 11.
// Find the next match.
position = StringMatch(string, searchString, endOfLastMatch);
} while (position >= 0);
// Step 15.
// Append the substring after the last match.
return result.append(strChars + endOfLastMatch,
stringLength - endOfLastMatch);
}
// Steps 7-16 when functionalReplace is false and searchString is not empty.
//
// The steps are quite different, for performance. Loops in steps 11 and 14
// are fused. GetSubstitution is optimized away when possible.
template <typename StrChar, typename RepChar>
static JSString* ReplaceAll(JSContext* cx, JSLinearString* string,
JSLinearString* searchString,
JSLinearString* replaceString) {
// Step 7 moved into ReplaceAll_internal.
// Step 8 (advanceBy is equal to searchLength when searchLength > 0).
// Step 9 (not needed in this implementation).
// Step 10.
// Find the first match.
int32_t position = StringMatch(string, searchString, 0);
// Nothing to replace, so return early.
if (position < 0) {
return string;
}
// Steps 11, 12 moved into ReplaceAll_internal.
// Step 13.
JSStringBuilder result(cx);
if constexpr (std::is_same_v<StrChar, char16_t> ||
std::is_same_v<RepChar, char16_t>) {
if (!result.ensureTwoByteChars()) {
return nullptr;
}
}
bool internalFailure = false;
{
AutoCheckCannotGC nogc;
internalFailure = !ReplaceAllInternal<StrChar, RepChar>(
nogc, string, searchString, replaceString, position, result);
}
if (internalFailure) {
return nullptr;
}
// Step 16.
return result.finishString();
}
template <typename StrChar, typename RepChar>
static bool ReplaceAllInterleaveInternal(const AutoCheckCannotGC& nogc,
JSContext* cx, JSLinearString* string,
JSLinearString* replaceString,
JSStringBuilder& result) {
// Step 7.
const size_t stringLength = string->length();
const size_t replaceLength = replaceString->length();
const StrChar* strChars = string->chars<StrChar>(nogc);
const RepChar* repChars = replaceString->chars<RepChar>(nogc);
uint32_t dollarIndex = FindDollarIndex(repChars, replaceLength);
if (dollarIndex != UINT32_MAX) {
if (!result.reserve(stringLength)) {
return false;
}
} else {
// Compute the exact result length when no substitutions take place.
CheckedInt<uint32_t> strLength(stringLength);
CheckedInt<uint32_t> repLength(replaceLength);
CheckedInt<uint32_t> length = strLength + (strLength + 1) * repLength;
if (!length.isValid()) {
ReportAllocationOverflow(cx);
return false;
}
if (!result.reserve(length.value())) {
return false;
}
}
auto appendReplacement = [&](size_t match) {
if (dollarIndex != UINT32_MAX) {
return AppendDollarReplacement(result, dollarIndex, match, match, string,
repChars, replaceLength);
}
return result.append(repChars, replaceLength);
};
for (size_t index = 0; index < stringLength; index++) {
// Steps 11, 14.a-b and 14.d.
// The empty string matches before each character.
if (!appendReplacement(index)) {
return false;
}
// Step 14.c.
if (!result.append(strChars[index])) {
return false;
}
}
// Steps 11, 14.a-b and 14.d.
// The empty string also matches at the end of the string.
return appendReplacement(stringLength);
// Step 15 (not applicable when searchString is the empty string).
}
// Steps 7-16 when functionalReplace is false and searchString is the empty
// string.
//
// The steps are quite different, for performance. Loops in steps 11 and 14
// are fused. GetSubstitution is optimized away when possible.
template <typename StrChar, typename RepChar>
static JSString* ReplaceAllInterleave(JSContext* cx, JSLinearString* string,
JSLinearString* replaceString) {
// Step 7 moved into ReplaceAllInterleavedInternal.
// Step 8 (advanceBy is 1 when searchString is the empty string).
// Steps 9-12 (trivial when searchString is the empty string).
// Step 13.
JSStringBuilder result(cx);
if constexpr (std::is_same_v<StrChar, char16_t> ||
std::is_same_v<RepChar, char16_t>) {
if (!result.ensureTwoByteChars()) {
return nullptr;
}
}
bool internalFailure = false;
{
AutoCheckCannotGC nogc;
internalFailure = !ReplaceAllInterleaveInternal<StrChar, RepChar>(
nogc, cx, string, replaceString, result);
}
if (internalFailure) {
return nullptr;
}
// Step 16.
return result.finishString();
}
// String.prototype.replaceAll (Stage 3 proposal)
//
// String.prototype.replaceAll ( searchValue, replaceValue )
//
// Steps 7-16 when functionalReplace is false.
JSString* js::str_replaceAll_string_raw(JSContext* cx, HandleString string,
HandleString searchString,
HandleString replaceString) {
const size_t stringLength = string->length();
const size_t searchLength = searchString->length();
// Directly return when we're guaranteed to find no match.
if (searchLength > stringLength) {
return string;
}
Rooted<JSLinearString*> str(cx, string->ensureLinear(cx));
if (!str) {
return nullptr;
}
Rooted<JSLinearString*> repl(cx, replaceString->ensureLinear(cx));
if (!repl) {
return nullptr;
}
Rooted<JSLinearString*> search(cx, searchString->ensureLinear(cx));
if (!search) {
return nullptr;
}
// The pattern is empty, so we interleave the replacement string in-between
// each character.
if (searchLength == 0) {
if (str->hasTwoByteChars()) {
if (repl->hasTwoByteChars()) {
return ReplaceAllInterleave<char16_t, char16_t>(cx, str, repl);
}
return ReplaceAllInterleave<char16_t, Latin1Char>(cx, str, repl);
}
if (repl->hasTwoByteChars()) {
return ReplaceAllInterleave<Latin1Char, char16_t>(cx, str, repl);
}
return ReplaceAllInterleave<Latin1Char, Latin1Char>(cx, str, repl);
}
MOZ_ASSERT(stringLength > 0);
if (str->hasTwoByteChars()) {
if (repl->hasTwoByteChars()) {
return ReplaceAll<char16_t, char16_t>(cx, str, search, repl);
}
return ReplaceAll<char16_t, Latin1Char>(cx, str, search, repl);
}
if (repl->hasTwoByteChars()) {
return ReplaceAll<Latin1Char, char16_t>(cx, str, search, repl);
}
return ReplaceAll<Latin1Char, Latin1Char>(cx, str, search, repl);
}
static ArrayObject* SingleElementStringArray(JSContext* cx,
Handle<JSLinearString*> str) {
ArrayObject* array = NewDenseFullyAllocatedArray(cx, 1);
if (!array) {
return nullptr;
}
array->setDenseInitializedLength(1);
array->initDenseElement(0, StringValue(str));
return array;
}
// ES 2016 draft Mar 25, 2016 21.1.3.17 steps 4, 8, 12-18.
static ArrayObject* SplitHelper(JSContext* cx, Handle<JSLinearString*> str,
uint32_t limit, Handle<JSLinearString*> sep) {
size_t strLength = str->length();
size_t sepLength = sep->length();
MOZ_ASSERT(sepLength != 0);
// Step 12.
if (strLength == 0) {
// Step 12.a.
int match = StringMatch(str, sep, 0);
// Step 12.b.
if (match != -1) {
return NewDenseEmptyArray(cx);
}
// Steps 12.c-e.
return SingleElementStringArray(cx, str);
}
// Step 3 (reordered).
RootedValueVector splits(cx);
// Step 8 (reordered).
size_t lastEndIndex = 0;
// Step 13.
size_t index = 0;
// Step 14.
while (index != strLength) {
// Step 14.a.
int match = StringMatch(str, sep, index);
// Step 14.b.
//
// Our match algorithm differs from the spec in that it returns the
// next index at which a match happens. If no match happens we're
// done.
//
// But what if the match is at the end of the string (and the string is
// not empty)? Per 14.c.i this shouldn't be a match, so we have to
// specially exclude it. Thus this case should hold:
//
// var a = "abc".split(/\b/);
// assertEq(a.length, 1);
// assertEq(a[0], "abc");
if (match == -1) {
break;
}
// Step 14.c.
size_t endIndex = match + sepLength;
// Step 14.c.i.
if (endIndex == lastEndIndex) {
index++;
continue;
}
// Step 14.c.ii.
MOZ_ASSERT(lastEndIndex < endIndex);
MOZ_ASSERT(sepLength <= strLength);
MOZ_ASSERT(lastEndIndex + sepLength <= endIndex);
// Step 14.c.ii.1.
size_t subLength = size_t(endIndex - sepLength - lastEndIndex);
JSString* sub = NewDependentString(cx, str, lastEndIndex, subLength);
// Steps 14.c.ii.2-4.
if (!sub || !splits.append(StringValue(sub))) {
return nullptr;
}
// Step 14.c.ii.5.
if (splits.length() == limit) {
return NewDenseCopiedArray(cx, splits.length(), splits.begin());
}
// Step 14.c.ii.6.
index = endIndex;
// Step 14.c.ii.7.
lastEndIndex = index;
}
// Step 15.
JSString* sub =
NewDependentString(cx, str, lastEndIndex, strLength - lastEndIndex);
// Steps 16-17.
if (!sub || !splits.append(StringValue(sub))) {
return nullptr;
}
// Step 18.
return NewDenseCopiedArray(cx, splits.length(), splits.begin());
}
// Fast-path for splitting a string into a character array via split("").
static ArrayObject* CharSplitHelper(JSContext* cx, Handle<JSLinearString*> str,
uint32_t limit) {
size_t strLength = str->length();
if (strLength == 0) {
return NewDenseEmptyArray(cx);
}
js::StaticStrings& staticStrings = cx->staticStrings();
uint32_t resultlen = (limit < strLength ? limit : strLength);
MOZ_ASSERT(limit > 0 && resultlen > 0,
"Neither limit nor strLength is zero, so resultlen is greater "
"than zero.");
Rooted<ArrayObject*> splits(cx, NewDenseFullyAllocatedArray(cx, resultlen));
if (!splits) {
return nullptr;
}
if (str->hasLatin1Chars()) {
splits->setDenseInitializedLength(resultlen);
JS::AutoCheckCannotGC nogc;
const Latin1Char* latin1Chars = str->latin1Chars(nogc);
for (size_t i = 0; i < resultlen; ++i) {
Latin1Char c = latin1Chars[i];
MOZ_ASSERT(staticStrings.hasUnit(c));
splits->initDenseElement(i, StringValue(staticStrings.getUnit(c)));
}
} else {
splits->ensureDenseInitializedLength(0, resultlen);
for (size_t i = 0; i < resultlen; ++i) {
JSString* sub = staticStrings.getUnitStringForElement(cx, str, i);
if (!sub) {
return nullptr;
}
splits->initDenseElement(i, StringValue(sub));
}
}
return splits;
}
template <typename TextChar>
static MOZ_ALWAYS_INLINE ArrayObject* SplitSingleCharHelper(
JSContext* cx, Handle<JSLinearString*> str, const TextChar* text,
uint32_t textLen, char16_t patCh) {
// Count the number of occurrences of patCh within text.
uint32_t count = 0;
for (size_t index = 0; index < textLen; index++) {
if (static_cast<char16_t>(text[index]) == patCh) {
count++;
}
}
// Handle zero-occurrence case - return input string in an array.
if (count == 0) {
return SingleElementStringArray(cx, str);
}
// Create the result array for the substring values.
Rooted<ArrayObject*> splits(cx, NewDenseFullyAllocatedArray(cx, count + 1));
if (!splits) {
return nullptr;
}
splits->ensureDenseInitializedLength(0, count + 1);
// Add substrings.
uint32_t splitsIndex = 0;
size_t lastEndIndex = 0;
for (size_t index = 0; index < textLen; index++) {
if (static_cast<char16_t>(text[index]) == patCh) {
size_t subLength = size_t(index - lastEndIndex);
JSString* sub = NewDependentString(cx, str, lastEndIndex, subLength);
if (!sub) {
return nullptr;
}
splits->initDenseElement(splitsIndex++, StringValue(sub));
lastEndIndex = index + 1;
}
}
// Add substring for tail of string (after last match).
JSString* sub =
NewDependentString(cx, str, lastEndIndex, textLen - lastEndIndex);
if (!sub) {
return nullptr;
}
splits->initDenseElement(splitsIndex++, StringValue(sub));
return splits;
}
// ES 2016 draft Mar 25, 2016 21.1.3.17 steps 4, 8, 12-18.
static ArrayObject* SplitSingleCharHelper(JSContext* cx,
Handle<JSLinearString*> str,
char16_t ch) {
// Step 12.
size_t strLength = str->length();
AutoStableStringChars linearChars(cx);
if (!linearChars.init(cx, str)) {
return nullptr;
}
if (linearChars.isLatin1()) {
return SplitSingleCharHelper(cx, str, linearChars.latin1Chars(), strLength,
ch);
}
return SplitSingleCharHelper(cx, str, linearChars.twoByteChars(), strLength,
ch);
}
// ES 2016 draft Mar 25, 2016 21.1.3.17 steps 4, 8, 12-18.
ArrayObject* js::StringSplitString(JSContext* cx, HandleString str,
HandleString sep, uint32_t limit) {
MOZ_ASSERT(limit > 0, "Only called for strictly positive limit.");
Rooted<JSLinearString*> linearStr(cx, str->ensureLinear(cx));
if (!linearStr) {
return nullptr;
}
Rooted<JSLinearString*> linearSep(cx, sep->ensureLinear(cx));
if (!linearSep) {
return nullptr;
}
if (linearSep->length() == 0) {
return CharSplitHelper(cx, linearStr, limit);
}
if (linearSep->length() == 1 && limit >= static_cast<uint32_t>(INT32_MAX)) {
char16_t ch = linearSep->latin1OrTwoByteChar(0);
return SplitSingleCharHelper(cx, linearStr, ch);
}
return SplitHelper(cx, linearStr, limit, linearSep);
}
static const JSFunctionSpec string_methods[] = {
JS_FN("toSource", str_toSource, 0, 0),
/* Java-like methods. */
JS_INLINABLE_FN("toString", str_toString, 0, 0, StringToString),
JS_INLINABLE_FN("valueOf", str_toString, 0, 0, StringValueOf),
JS_INLINABLE_FN("toLowerCase", str_toLowerCase, 0, 0, StringToLowerCase),
JS_INLINABLE_FN("toUpperCase", str_toUpperCase, 0, 0, StringToUpperCase),
JS_INLINABLE_FN("charAt", str_charAt, 1, 0, StringCharAt),
JS_INLINABLE_FN("charCodeAt", str_charCodeAt, 1, 0, StringCharCodeAt),
JS_INLINABLE_FN("codePointAt", str_codePointAt, 1, 0, StringCodePointAt),
JS_INLINABLE_FN("at", str_at, 1, 0, StringAt),
JS_SELF_HOSTED_FN("substring", "String_substring", 2, 0),
JS_SELF_HOSTED_FN("padStart", "String_pad_start", 2, 0),
JS_SELF_HOSTED_FN("padEnd", "String_pad_end", 2, 0),
JS_INLINABLE_FN("includes", str_includes, 1, 0, StringIncludes),
JS_INLINABLE_FN("indexOf", str_indexOf, 1, 0, StringIndexOf),
JS_INLINABLE_FN("lastIndexOf", str_lastIndexOf, 1, 0, StringLastIndexOf),
JS_INLINABLE_FN("startsWith", str_startsWith, 1, 0, StringStartsWith),
JS_INLINABLE_FN("endsWith", str_endsWith, 1, 0, StringEndsWith),
JS_INLINABLE_FN("trim", str_trim, 0, 0, StringTrim),
JS_INLINABLE_FN("trimStart", str_trimStart, 0, 0, StringTrimStart),
JS_INLINABLE_FN("trimEnd", str_trimEnd, 0, 0, StringTrimEnd),
#if JS_HAS_INTL_API
JS_SELF_HOSTED_FN("toLocaleLowerCase", "String_toLocaleLowerCase", 0, 0),
JS_SELF_HOSTED_FN("toLocaleUpperCase", "String_toLocaleUpperCase", 0, 0),
JS_SELF_HOSTED_FN("localeCompare", "String_localeCompare", 1, 0),
#else
JS_FN("toLocaleLowerCase", str_toLocaleLowerCase, 0, 0),
JS_FN("toLocaleUpperCase", str_toLocaleUpperCase, 0, 0),
JS_FN("localeCompare", str_localeCompare, 1, 0),
#endif
JS_SELF_HOSTED_FN("repeat", "String_repeat", 1, 0),
#if JS_HAS_INTL_API
JS_FN("normalize", str_normalize, 0, 0),
#endif
/* Perl-ish methods (search is actually Python-esque). */
JS_SELF_HOSTED_FN("match", "String_match", 1, 0),
JS_SELF_HOSTED_FN("matchAll", "String_matchAll", 1, 0),
JS_SELF_HOSTED_FN("search", "String_search", 1, 0),
JS_SELF_HOSTED_FN("replace", "String_replace", 2, 0),
JS_SELF_HOSTED_FN("replaceAll", "String_replaceAll", 2, 0),
JS_SELF_HOSTED_FN("split", "String_split", 2, 0),
JS_SELF_HOSTED_FN("substr", "String_substr", 2, 0),
/* Python-esque sequence methods. */
JS_SELF_HOSTED_FN("concat", "String_concat", 1, 0),
JS_SELF_HOSTED_FN("slice", "String_slice", 2, 0),
/* HTML string methods. */
JS_SELF_HOSTED_FN("bold", "String_bold", 0, 0),
JS_SELF_HOSTED_FN("italics", "String_italics", 0, 0),
JS_SELF_HOSTED_FN("fixed", "String_fixed", 0, 0),
JS_SELF_HOSTED_FN("strike", "String_strike", 0, 0),
JS_SELF_HOSTED_FN("small", "String_small", 0, 0),
JS_SELF_HOSTED_FN("big", "String_big", 0, 0),
JS_SELF_HOSTED_FN("blink", "String_blink", 0, 0),
JS_SELF_HOSTED_FN("sup", "String_sup", 0, 0),
JS_SELF_HOSTED_FN("sub", "String_sub", 0, 0),
JS_SELF_HOSTED_FN("anchor", "String_anchor", 1, 0),
JS_SELF_HOSTED_FN("link", "String_link", 1, 0),
JS_SELF_HOSTED_FN("fontcolor", "String_fontcolor", 1, 0),
JS_SELF_HOSTED_FN("fontsize", "String_fontsize", 1, 0),
JS_SELF_HOSTED_SYM_FN(iterator, "String_iterator", 0, 0),
JS_FS_END,
};
// ES6 rev 27 (2014 Aug 24) 21.1.1
bool js::StringConstructor(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
RootedString str(cx);
if (args.length() > 0) {
if (!args.isConstructing() && args[0].isSymbol()) {
return js::SymbolDescriptiveString(cx, args[0].toSymbol(), args.rval());
}
str = ToString<CanGC>(cx, args[0]);
if (!str) {
return false;
}
} else {
str = cx->runtime()->emptyString;
}
if (args.isConstructing()) {
RootedObject proto(cx);
if (!GetPrototypeFromBuiltinConstructor(cx, args, JSProto_String, &proto)) {
return false;
}
StringObject* strobj = StringObject::create(cx, str, proto);
if (!strobj) {
return false;
}
args.rval().setObject(*strobj);
return true;
}
args.rval().setString(str);
return true;
}
static inline JSLinearString* CodeUnitToString(JSContext* cx, char16_t code) {
if (StaticStrings::hasUnit(code)) {
return cx->staticStrings().getUnit(code);
}
return NewInlineString<CanGC>(cx, {code}, 1);
}
JSLinearString* js::StringFromCharCode(JSContext* cx, int32_t charCode) {
return CodeUnitToString(cx, char16_t(charCode));
}
JSLinearString* js::StringFromCodePoint(JSContext* cx, char32_t codePoint) {
MOZ_ASSERT(codePoint <= unicode::NonBMPMax);
if (!unicode::IsSupplementary(codePoint)) {
return CodeUnitToString(cx, char16_t(codePoint));
}
char16_t chars[] = {unicode::LeadSurrogate(codePoint),
unicode::TrailSurrogate(codePoint)};
return NewInlineString<CanGC>(cx, chars, 2);
}
/**
* 22.1.2.1 String.fromCharCode ( ...codeUnits )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
bool js::str_fromCharCode(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
MOZ_ASSERT(args.length() <= ARGS_LENGTH_MAX);
// Optimize the single-char case.
if (args.length() == 1) {
uint16_t code;
if (!ToUint16(cx, args[0], &code)) {
return false;
}
JSString* str = CodeUnitToString(cx, char16_t(code));
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
// Optimize the case where the result will definitely fit in an inline
// string (thin or fat) and so we don't need to malloc the chars. (We could
// cover some cases where args.length() goes up to
// JSFatInlineString::MAX_LENGTH_LATIN1 if we also checked if the chars are
// all Latin-1, but it doesn't seem worth the effort.)
InlineCharBuffer<char16_t> chars;
if (!chars.maybeAlloc(cx, args.length())) {
return false;
}
char16_t* rawChars = chars.get();
for (unsigned i = 0; i < args.length(); i++) {
uint16_t code;
if (!ToUint16(cx, args[i], &code)) {
return false;
}
rawChars[i] = char16_t(code);
}
JSString* str = chars.toString(cx, args.length());
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
/**
* 22.1.2.2 String.fromCodePoint ( ...codePoints )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
static MOZ_ALWAYS_INLINE bool ToCodePoint(JSContext* cx, HandleValue code,
char32_t* codePoint) {
// String.fromCodePoint, Steps 2.a-d.
// Fast path for the common case - the input is already an int32.
if (code.isInt32()) {
// Step 2.a.
int32_t nextCP = code.toInt32();
// Steps 2.b-d.
if (MOZ_LIKELY(uint32_t(nextCP) <= unicode::NonBMPMax)) {
*codePoint = char32_t(nextCP);
return true;
}
}
// Step 2.a.
double nextCP;
if (!ToNumber(cx, code, &nextCP)) {
return false;
}
// Steps 2.b-c.
if (JS::ToInteger(nextCP) != nextCP || nextCP < 0 ||
nextCP > unicode::NonBMPMax) {
ToCStringBuf cbuf;
const char* numStr = NumberToCString(&cbuf, nextCP);
MOZ_ASSERT(numStr);
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
JSMSG_NOT_A_CODEPOINT, numStr);
return false;
}
// Steps 2.d.
*codePoint = char32_t(nextCP);
return true;
}
/**
* 22.1.2.2 String.fromCodePoint ( ...codePoints )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
static bool str_fromCodePoint_few_args(JSContext* cx, const CallArgs& args) {
MOZ_ASSERT(args.length() <= JSFatInlineString::MAX_LENGTH_TWO_BYTE / 2);
// Step 1.
char16_t elements[JSFatInlineString::MAX_LENGTH_TWO_BYTE];
// Step 2.
unsigned length = 0;
for (unsigned nextIndex = 0; nextIndex < args.length(); nextIndex++) {
// Steps 2.a-c.
char32_t codePoint;
if (!ToCodePoint(cx, args[nextIndex], &codePoint)) {
return false;
}
// Step 2.d.
unicode::UTF16Encode(codePoint, elements, &length);
}
// Steps 3-4.
JSString* str = NewStringCopyN<CanGC>(cx, elements, length);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
/**
* 22.1.2.2 String.fromCodePoint ( ...codePoints )
*
* ES2024 draft rev 7d2644968bd56d54d2886c012d18698ff3f72c35
*/
bool js::str_fromCodePoint(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
// Optimize the single code-point case.
if (args.length() == 1) {
// Step 1. (Omitted)
// Step 2.
char32_t codePoint;
if (!ToCodePoint(cx, args[0], &codePoint)) {
return false;
}
// Steps 3-4.
JSString* str = StringFromCodePoint(cx, codePoint);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
// Optimize the case where the result will definitely fit in an inline
// string (thin or fat) and so we don't need to malloc the chars. (We could
// cover some cases where |args.length()| goes up to
// JSFatInlineString::MAX_LENGTH_LATIN1 / 2 if we also checked if the chars
// are all Latin-1, but it doesn't seem worth the effort.)
if (args.length() <= JSFatInlineString::MAX_LENGTH_TWO_BYTE / 2) {
return str_fromCodePoint_few_args(cx, args);
}
// Step 1.
static_assert(
ARGS_LENGTH_MAX < std::numeric_limits<decltype(args.length())>::max() / 2,
"|args.length() * 2| does not overflow");
auto elements = cx->make_pod_arena_array<char16_t>(js::StringBufferArena,
args.length() * 2);
if (!elements) {
return false;
}
// Steps 2.
unsigned length = 0;
for (unsigned nextIndex = 0; nextIndex < args.length(); nextIndex++) {
// Steps 2.a-c.
char32_t codePoint;
if (!ToCodePoint(cx, args[nextIndex], &codePoint)) {
return false;
}
// Step 2.d.
unicode::UTF16Encode(codePoint, elements.get(), &length);
}
// Steps 3-4.
JSString* str = NewString<CanGC>(cx, std::move(elements), length);
if (!str) {
return false;
}
args.rval().setString(str);
return true;
}
static const JSFunctionSpec string_static_methods[] = {
JS_INLINABLE_FN("fromCharCode", js::str_fromCharCode, 1, 0,
StringFromCharCode),
JS_INLINABLE_FN("fromCodePoint", js::str_fromCodePoint, 1, 0,
StringFromCodePoint),
JS_SELF_HOSTED_FN("raw", "String_static_raw", 1, 0),
JS_FS_END,
};
/* static */
SharedShape* StringObject::assignInitialShape(JSContext* cx,
Handle<StringObject*> obj) {
MOZ_ASSERT(obj->empty());
if (!NativeObject::addPropertyInReservedSlot(cx, obj, cx->names().length,
LENGTH_SLOT, {})) {
return nullptr;
}
return obj->sharedShape();
}
JSObject* StringObject::createPrototype(JSContext* cx, JSProtoKey key) {
Rooted<JSString*> empty(cx, cx->runtime()->emptyString);
// Because the `length` property of a StringObject is both non-configurable
// and non-writable, we need to take the slow path of proxy result
// validation for them, and so we need to ensure that the initial ObjectFlags
// reflect that. Normally this would be handled for us, but the special
// SharedShape::ensureInitialCustomShape path which ultimately takes us
// through StringObject::assignInitialShape which adds the problematic
// property sneaks past our flag setting logic and results in a failed
// lookup of the initial shape in SharedShape::insertInitialShape.
Rooted<StringObject*> proto(
cx, GlobalObject::createBlankPrototype<StringObject>(
cx, cx->global(),
ObjectFlags({ObjectFlag::NeedsProxyGetSetResultValidation})));
if (!proto) {
return nullptr;
}
if (!StringObject::init(cx, proto, empty)) {
return nullptr;
}
return proto;
}
static bool StringClassFinish(JSContext* cx, HandleObject ctor,
HandleObject proto) {
Handle<NativeObject*> nativeProto = proto.as<NativeObject>();
// Create "trimLeft" as an alias for "trimStart".
RootedValue trimFn(cx);
RootedId trimId(cx, NameToId(cx->names().trimStart));
RootedId trimAliasId(cx, NameToId(cx->names().trimLeft));
if (!NativeGetProperty(cx, nativeProto, trimId, &trimFn) ||
!NativeDefineDataProperty(cx, nativeProto, trimAliasId, trimFn, 0)) {
return false;
}
// Create "trimRight" as an alias for "trimEnd".
trimId = NameToId(cx->names().trimEnd);
trimAliasId = NameToId(cx->names().trimRight);
if (!NativeGetProperty(cx, nativeProto, trimId, &trimFn) ||
!NativeDefineDataProperty(cx, nativeProto, trimAliasId, trimFn, 0)) {
return false;
}
/*
* Define escape/unescape, the URI encode/decode functions, and maybe
* uneval on the global object.
*/
if (!JS_DefineFunctions(cx, cx->global(), string_functions)) {
return false;
}
// Define isWellFormed/toWellFormed functions.
if (JS::Prefs::well_formed_unicode_strings() &&
!JS_DefineFunctions(cx, nativeProto, wellFormed_functions)) {
return false;
}
return true;
}
const ClassSpec StringObject::classSpec_ = {
GenericCreateConstructor<StringConstructor, 1, gc::AllocKind::FUNCTION,
&jit::JitInfo_String>,
StringObject::createPrototype,
string_static_methods,
nullptr,
string_methods,
nullptr,
StringClassFinish};
#define ____ false
/*
* Uri reserved chars + #:
* - 35: #
* - 36: $
* - 38: &
* - 43: +
* - 44: ,
* - 47: /
* - 58: :
* - 59: ;
* - 61: =
* - 63: ?
* - 64: @
*/
static const bool js_isUriReservedPlusPound[] = {
// clang-format off
/* 0 1 2 3 4 5 6 7 8 9 */
/* 0 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 1 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 2 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 3 */ ____, ____, ____, ____, ____, true, true, ____, true, ____,
/* 4 */ ____, ____, ____, true, true, ____, ____, true, ____, ____,
/* 5 */ ____, ____, ____, ____, ____, ____, ____, ____, true, true,
/* 6 */ ____, true, ____, true, true, ____, ____, ____, ____, ____,
/* 7 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 8 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 9 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 10 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 11 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 12 */ ____, ____, ____, ____, ____, ____, ____, ____
// clang-format on
};
/*
* Uri unescaped chars:
* - 33: !
* - 39: '
* - 40: (
* - 41: )
* - 42: *
* - 45: -
* - 46: .
* - 48..57: 0-9
* - 65..90: A-Z
* - 95: _
* - 97..122: a-z
* - 126: ~
*/
static const bool js_isUriUnescaped[] = {
// clang-format off
/* 0 1 2 3 4 5 6 7 8 9 */
/* 0 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 1 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 2 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
/* 3 */ ____, ____, ____, true, ____, ____, ____, ____, ____, true,
/* 4 */ true, true, true, ____, ____, true, true, ____, true, true,
/* 5 */ true, true, true, true, true, true, true, true, ____, ____,
/* 6 */ ____, ____, ____, ____, ____, true, true, true, true, true,
/* 7 */ true, true, true, true, true, true, true, true, true, true,
/* 8 */ true, true, true, true, true, true, true, true, true, true,
/* 9 */ true, ____, ____, ____, ____, true, ____, true, true, true,
/* 10 */ true, true, true, true, true, true, true, true, true, true,
/* 11 */ true, true, true, true, true, true, true, true, true, true,
/* 12 */ true, true, true, ____, ____, ____, true, ____
// clang-format on
};
#undef ____
static inline bool TransferBufferToString(JSStringBuilder& sb, JSString* str,
MutableHandleValue rval) {
if (!sb.empty()) {
str = sb.finishString();
if (!str) {
return false;
}
}
rval.setString(str);
return true;
}
/*
* ECMA 3, 15.1.3 URI Handling Function Properties
*
* The following are implementations of the algorithms
* given in the ECMA specification for the hidden functions
* 'Encode' and 'Decode'.
*/
enum EncodeResult { Encode_Failure, Encode_BadUri, Encode_Success };
// caller Encode function. Annotate both functions with MOZ_NEVER_INLINE resp.
// MOZ_ALWAYS_INLINE to ensure we get the desired inlining behavior.
template <typename CharT>
static MOZ_NEVER_INLINE EncodeResult Encode(StringBuffer& sb,
const CharT* chars, size_t length,
const bool* unescapedSet) {
Latin1Char hexBuf[3];
hexBuf[0] = '%';
auto appendEncoded = [&sb, &hexBuf](Latin1Char c) {
static const char HexDigits[] = "0123456789ABCDEF"; /* NB: uppercase */
hexBuf[1] = HexDigits[c >> 4];
hexBuf[2] = HexDigits[c & 0xf];
return sb.append(hexBuf, 3);
};
auto appendRange = [&sb, chars, length](size_t start, size_t end) {
MOZ_ASSERT(start <= end);
if (start < end) {
if (start == 0) {
if (!sb.reserve(length)) {
return false;
}
}
return sb.append(chars + start, chars + end);
}
return true;
};
size_t startAppend = 0;
for (size_t k = 0; k < length; k++) {
CharT c = chars[k];
if (c < 128 &&
(js_isUriUnescaped[c] || (unescapedSet && unescapedSet[c]))) {
continue;
} else {
if (!appendRange(startAppend, k)) {
return Encode_Failure;
}
if constexpr (std::is_same_v<CharT, Latin1Char>) {
if (c < 0x80) {
if (!appendEncoded(c)) {
return Encode_Failure;
}
} else {
if (!appendEncoded(0xC0 | (c >> 6)) ||
!appendEncoded(0x80 | (c & 0x3F))) {
return Encode_Failure;
}
}
} else {
if (unicode::IsTrailSurrogate(c)) {
return Encode_BadUri;
}
char32_t v;
if (!unicode::IsLeadSurrogate(c)) {
v = c;
} else {
k++;
if (k == length) {
return Encode_BadUri;
}
char16_t c2 = chars[k];
if (!unicode::IsTrailSurrogate(c2)) {
return Encode_BadUri;
}
v = unicode::UTF16Decode(c, c2);
}
uint8_t utf8buf[4];
size_t L = OneUcs4ToUtf8Char(utf8buf, v);
for (size_t j = 0; j < L; j++) {
if (!appendEncoded(utf8buf[j])) {
return Encode_Failure;
}
}
}
startAppend = k + 1;
}
}
if (startAppend > 0) {
if (!appendRange(startAppend, length)) {
return Encode_Failure;
}
}
return Encode_Success;
}
static MOZ_ALWAYS_INLINE bool Encode(JSContext* cx, Handle<JSLinearString*> str,
const bool* unescapedSet,
MutableHandleValue rval) {
size_t length = str->length();
if (length == 0) {
rval.setString(cx->runtime()->emptyString);
return true;
}
JSStringBuilder sb(cx);
EncodeResult res;
if (str->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
res = Encode(sb, str->latin1Chars(nogc), str->length(), unescapedSet);
} else {
AutoCheckCannotGC nogc;
res = Encode(sb, str->twoByteChars(nogc), str->length(), unescapedSet);
}
if (res == Encode_Failure) {
return false;
}
if (res == Encode_BadUri) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_URI);
return false;
}
MOZ_ASSERT(res == Encode_Success);
return TransferBufferToString(sb, str, rval);
}
enum DecodeResult { Decode_Failure, Decode_BadUri, Decode_Success };
template <typename CharT>
static DecodeResult Decode(StringBuffer& sb, const CharT* chars, size_t length,
const bool* reservedSet) {
auto appendRange = [&sb, chars](size_t start, size_t end) {
MOZ_ASSERT(start <= end);
if (start < end) {
return sb.append(chars + start, chars + end);
}
return true;
};
size_t startAppend = 0;
for (size_t k = 0; k < length; k++) {
CharT c = chars[k];
if (c == '%') {
size_t start = k;
if ((k + 2) >= length) {
return Decode_BadUri;
}
if (!IsAsciiHexDigit(chars[k + 1]) || !IsAsciiHexDigit(chars[k + 2])) {
return Decode_BadUri;
}
uint32_t B = AsciiAlphanumericToNumber(chars[k + 1]) * 16 +
AsciiAlphanumericToNumber(chars[k + 2]);
k += 2;
if (B < 128) {
Latin1Char ch = Latin1Char(B);
if (reservedSet && reservedSet[ch]) {
continue;
}
if (!appendRange(startAppend, start)) {
return Decode_Failure;
}
if (!sb.append(ch)) {
return Decode_Failure;
}
} else {
int n = 1;
while (B & (0x80 >> n)) {
n++;
}
if (n == 1 || n > 4) {
return Decode_BadUri;
}
uint8_t octets[4];
octets[0] = (uint8_t)B;
if (k + 3 * (n - 1) >= length) {
return Decode_BadUri;
}
for (int j = 1; j < n; j++) {
k++;
if (chars[k] != '%') {
return Decode_BadUri;
}
if (!IsAsciiHexDigit(chars[k + 1]) ||
!IsAsciiHexDigit(chars[k + 2])) {
return Decode_BadUri;
}
B = AsciiAlphanumericToNumber(chars[k + 1]) * 16 +
AsciiAlphanumericToNumber(chars[k + 2]);
if ((B & 0xC0) != 0x80) {
return Decode_BadUri;
}
k += 2;
octets[j] = char(B);
}
if (!appendRange(startAppend, start)) {
return Decode_Failure;
}
char32_t v = JS::Utf8ToOneUcs4Char(octets, n);
MOZ_ASSERT(v >= 128);
if (v >= unicode::NonBMPMin) {
if (v > unicode::NonBMPMax) {
return Decode_BadUri;
}
if (!sb.append(unicode::LeadSurrogate(v))) {
return Decode_Failure;
}
if (!sb.append(unicode::TrailSurrogate(v))) {
return Decode_Failure;
}
} else {
if (!sb.append(char16_t(v))) {
return Decode_Failure;
}
}
}
startAppend = k + 1;
}
}
if (startAppend > 0) {
if (!appendRange(startAppend, length)) {
return Decode_Failure;
}
}
return Decode_Success;
}
static bool Decode(JSContext* cx, Handle<JSLinearString*> str,
const bool* reservedSet, MutableHandleValue rval) {
size_t length = str->length();
if (length == 0) {
rval.setString(cx->runtime()->emptyString);
return true;
}
JSStringBuilder sb(cx);
DecodeResult res;
if (str->hasLatin1Chars()) {
AutoCheckCannotGC nogc;
res = Decode(sb, str->latin1Chars(nogc), str->length(), reservedSet);
} else {
AutoCheckCannotGC nogc;
res = Decode(sb, str->twoByteChars(nogc), str->length(), reservedSet);
}
if (res == Decode_Failure) {
return false;
}
if (res == Decode_BadUri) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_URI);
return false;
}
MOZ_ASSERT(res == Decode_Success);
return TransferBufferToString(sb, str, rval);
}
static bool str_decodeURI(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "decodeURI");
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
return Decode(cx, str, js_isUriReservedPlusPound, args.rval());
}
static bool str_decodeURI_Component(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "decodeURIComponent");
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
return Decode(cx, str, nullptr, args.rval());
}
static bool str_encodeURI(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "encodeURI");
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
return Encode(cx, str, js_isUriReservedPlusPound, args.rval());
}
static bool str_encodeURI_Component(JSContext* cx, unsigned argc, Value* vp) {
AutoJSMethodProfilerEntry pseudoFrame(cx, "encodeURIComponent");
CallArgs args = CallArgsFromVp(argc, vp);
Rooted<JSLinearString*> str(cx, ArgToLinearString(cx, args, 0));
if (!str) {
return false;
}
return Encode(cx, str, nullptr, args.rval());
}
JSString* js::EncodeURI(JSContext* cx, const char* chars, size_t length) {
JSStringBuilder sb(cx);
EncodeResult result = Encode(sb, reinterpret_cast<const Latin1Char*>(chars),
length, js_isUriReservedPlusPound);
if (result == EncodeResult::Encode_Failure) {
return nullptr;
}
if (result == EncodeResult::Encode_BadUri) {
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_URI);
return nullptr;
}
if (sb.empty()) {
return NewStringCopyN<CanGC>(cx, chars, length);
}
return sb.finishString();
}
static bool FlatStringMatchHelper(JSContext* cx, HandleString str,
HandleString pattern, bool* isFlat,
int32_t* match) {
Rooted<JSLinearString*> linearPattern(cx, pattern->ensureLinear(cx));
if (!linearPattern) {
return false;
}
static const size_t MAX_FLAT_PAT_LEN = 256;
if (linearPattern->length() > MAX_FLAT_PAT_LEN ||
StringHasRegExpMetaChars(linearPattern)) {
*isFlat = false;
return true;
}
*isFlat = true;
if (str->isRope()) {
if (!RopeMatch(cx, &str->asRope(), linearPattern, match)) {
return false;
}
} else {
*match = StringMatch(&str->asLinear(), linearPattern);
}
return true;
}
static bool BuildFlatMatchArray(JSContext* cx, HandleString str,
HandleString pattern, int32_t match,
MutableHandleValue rval) {
if (match < 0) {
rval.setNull();
return true;
}
// Get the shape for the match result object.
Rooted<SharedShape*> shape(
cx, cx->global()->regExpRealm().getOrCreateMatchResultShape(cx));
if (!shape) {
return false;
}
Rooted<ArrayObject*> arr(cx,
NewDenseFullyAllocatedArrayWithShape(cx, 1, shape));
if (!arr) {
return false;
}
// Store a Value for each pair.
arr->setDenseInitializedLength(1);
arr->initDenseElement(0, StringValue(pattern));
// Set the |index| property.
arr->initSlot(RegExpRealm::MatchResultObjectIndexSlot, Int32Value(match));
// Set the |input| property.
arr->initSlot(RegExpRealm::MatchResultObjectInputSlot, StringValue(str));
#ifdef DEBUG
RootedValue test(cx);
RootedId id(cx, NameToId(cx->names().index));
if (!NativeGetProperty(cx, arr, id, &test)) {
return false;
}
MOZ_ASSERT(test == arr->getSlot(0));
id = NameToId(cx->names().input);
if (!NativeGetProperty(cx, arr, id, &test)) {
return false;
}
MOZ_ASSERT(test == arr->getSlot(1));
#endif
rval.setObject(*arr);
return true;
}
#ifdef DEBUG
static bool CallIsStringOptimizable(JSContext* cx, const char* name,
bool* result) {
FixedInvokeArgs<0> args(cx);
RootedValue rval(cx);
if (!CallSelfHostedFunction(cx, name, UndefinedHandleValue, args, &rval)) {
return false;
}
*result = rval.toBoolean();
return true;
}
#endif
bool js::FlatStringMatch(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
MOZ_ASSERT(args.length() == 2);
MOZ_ASSERT(args[0].isString());
MOZ_ASSERT(args[1].isString());
#ifdef DEBUG
bool isOptimizable = false;
if (!CallIsStringOptimizable(cx, "IsStringMatchOptimizable",
&isOptimizable)) {
return false;
}
MOZ_ASSERT(isOptimizable);
#endif
RootedString str(cx, args[0].toString());
RootedString pattern(cx, args[1].toString());
bool isFlat = false;
int32_t match = 0;
if (!FlatStringMatchHelper(cx, str, pattern, &isFlat, &match)) {
return false;
}
if (!isFlat) {
args.rval().setUndefined();
return true;
}
return BuildFlatMatchArray(cx, str, pattern, match, args.rval());
}
bool js::FlatStringSearch(JSContext* cx, unsigned argc, Value* vp) {
CallArgs args = CallArgsFromVp(argc, vp);
MOZ_ASSERT(args.length() == 2);
MOZ_ASSERT(args[0].isString());
MOZ_ASSERT(args[1].isString());
#ifdef DEBUG
bool isOptimizable = false;
if (!CallIsStringOptimizable(cx, "IsStringSearchOptimizable",
&isOptimizable)) {
return false;
}
MOZ_ASSERT(isOptimizable);
#endif
RootedString str(cx, args[0].toString());
RootedString pattern(cx, args[1].toString());
bool isFlat = false;
int32_t match = 0;
if (!FlatStringMatchHelper(cx, str, pattern, &isFlat, &match)) {
return false;
}
if (!isFlat) {
args.rval().setInt32(-2);
return true;
}
args.rval().setInt32(match);
return true;
}