The Tor Browser: comparison js/src/jsstr.cpp

--1:000000000000
+:3d720386d393
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+* vim: set ts=8 sts=4 et sw=4 tw=99:
+* This Source Code Form is subject to the terms of the Mozilla Public
+* License, v. 2.0. If a copy of the MPL was not distributed with this
+* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+/*
+* JS string type implementation.
+*
+* In order to avoid unnecessary js_LockGCThing/js_UnlockGCThing calls, these
+* native methods store strings (possibly newborn) converted from their 'this'
+* parameter and arguments on the stack: 'this' conversions at argv[-1], arg
+* conversions at their index (argv[0], argv[1]).  This is a legitimate method
+* of rooting things that might lose their newborn root due to subsequent GC
+* allocations in the same native method.
+*/
+#include "jsstr.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Casting.h"
+#include "mozilla/CheckedInt.h"
+#include "mozilla/FloatingPoint.h"
+#include "mozilla/PodOperations.h"
+#include <ctype.h>
+#include <string.h>
+#include "jsapi.h"
+#include "jsarray.h"
+#include "jsatom.h"
+#include "jsbool.h"
+#include "jscntxt.h"
+#include "jsgc.h"
+#include "jsnum.h"
+#include "jsobj.h"
+#include "jsopcode.h"
+#include "jstypes.h"
+#include "jsutil.h"
+#include "builtin/Intl.h"
+#include "builtin/RegExp.h"
+#if ENABLE_INTL_API
+#include "unicode/unorm.h"
+#endif
+#include "vm/GlobalObject.h"
+#include "vm/Interpreter.h"
+#include "vm/NumericConversions.h"
+#include "vm/Opcodes.h"
+#include "vm/RegExpObject.h"
+#include "vm/RegExpStatics.h"
+#include "vm/ScopeObject.h"
+#include "vm/StringBuffer.h"
+#include "jsinferinlines.h"
+#include "vm/Interpreter-inl.h"
+#include "vm/String-inl.h"
+#include "vm/StringObject-inl.h"
+using namespace js;
+using namespace js::gc;
+using namespace js::types;
+using namespace js::unicode;
+using mozilla::CheckedInt;
+using mozilla::IsNaN;
+using mozilla::IsNegativeZero;
+using mozilla::PodCopy;
+using mozilla::PodEqual;
+using mozilla::SafeCast;
+typedef Handle<JSLinearString*> HandleLinearString;
+static JSLinearString *
+ArgToRootedString(JSContext *cx, CallArgs &args, unsigned argno)
+{
+if (argno >= args.length())
+return cx->names().undefined;
+JSString *str = ToString<CanGC>(cx, args[argno]);
+if (!str)
+return nullptr;
+args[argno].setString(str);
+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 */
+static bool
+str_escape(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+static const char digits[] = {'0', '1', '2', '3', '4', '5', '6', '7',
+'8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+JSLinearString *str = ArgToRootedString(cx, args, 0);
+if (!str)
+return false;
+size_t length = str->length();
+const jschar *chars = str->chars();
+static const uint8_t shouldPassThrough[256] = {
+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  */
+1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,     /*   pqrstuvwxyz{\}~  DEL */
+};
+/* In step 7, exactly 69 characters should pass through unencoded. */
+#ifdef DEBUG
+size_t count = 0;
+for (size_t i = 0; i < sizeof(shouldPassThrough); i++) {
+if (shouldPassThrough[i]) {
+count++;
+}
+}
+JS_ASSERT(count == 69);
+#endif
+/* Take a first pass and see how big the result string will need to be. */
+size_t newlength = length;
+for (size_t i = 0; i < length; i++) {
+jschar ch = chars[i];
+if (ch < 128 && shouldPassThrough[ch])
+continue;
+/* The character will be encoded as %XX or %uXXXX. */
+newlength += (ch < 256) ? 2 : 5;
+/*
+* This overflow test works because newlength is incremented by at
+* most 5 on each iteration.
+*/
+if (newlength < length) {
+js_ReportAllocationOverflow(cx);
+return false;
+}
+}
+if (newlength >= ~(size_t)0 / sizeof(jschar)) {
+js_ReportAllocationOverflow(cx);
+return false;
+}
+jschar *newchars = cx->pod_malloc<jschar>(newlength + 1);
+if (!newchars)
+return false;
+size_t i, ni;
+for (i = 0, ni = 0; i < length; i++) {
+jschar ch = chars[i];
+if (ch < 128 && shouldPassThrough[ch]) {
+newchars[ni++] = ch;
+} else if (ch < 256) {
+newchars[ni++] = '%';
+newchars[ni++] = digits[ch >> 4];
+newchars[ni++] = digits[ch & 0xF];
+} else {
+newchars[ni++] = '%';
+newchars[ni++] = 'u';
+newchars[ni++] = digits[ch >> 12];
+newchars[ni++] = digits[(ch & 0xF00) >> 8];
+newchars[ni++] = digits[(ch & 0xF0) >> 4];
+newchars[ni++] = digits[ch & 0xF];
+}
+}
+JS_ASSERT(ni == newlength);
+newchars[newlength] = 0;
+JSString *retstr = js_NewString<CanGC>(cx, newchars, newlength);
+if (!retstr) {
+js_free(newchars);
+return false;
+}
+args.rval().setString(retstr);
+return true;
+}
+static inline bool
+Unhex4(const jschar *chars, jschar *result)
+{
+jschar a = chars[0],
+b = chars[1],
+c = chars[2],
+d = chars[3];
+if (!(JS7_ISHEX(a) && JS7_ISHEX(b) && JS7_ISHEX(c) && JS7_ISHEX(d)))
+return false;
+*result = (((((JS7_UNHEX(a) << 4) + JS7_UNHEX(b)) << 4) + JS7_UNHEX(c)) << 4) + JS7_UNHEX(d);
+return true;
+}
+static inline bool
+Unhex2(const jschar *chars, jschar *result)
+{
+jschar a = chars[0],
+b = chars[1];
+if (!(JS7_ISHEX(a) && JS7_ISHEX(b)))
+return false;
+*result = (JS7_UNHEX(a) << 4) + JS7_UNHEX(b);
+return true;
+}
+/* ES5 B.2.2 */
+static bool
+str_unescape(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+/* Step 1. */
+JSLinearString *str = ArgToRootedString(cx, args, 0);
+if (!str)
+return false;
+/*
+* NB: use signed integers for length/index to allow simple length
+* comparisons without unsigned-underflow hazards.
+*/
+JS_STATIC_ASSERT(JSString::MAX_LENGTH <= INT_MAX);
+/* Step 2. */
+int length = str->length();
+const jschar *chars = str->chars();
+/* Step 3. */
+StringBuffer sb(cx);
+/*
+* Note that the spec algorithm has been optimized to avoid building
+* a string in the case where no escapes are present.
+*/
+/* Step 4. */
+int k = 0;
+bool building = false;
+while (true) {
+/* Step 5. */
+if (k == length) {
+JSLinearString *result;
+if (building) {
+result = sb.finishString();
+if (!result)
+return false;
+} else {
+result = str;
+}
+args.rval().setString(result);
+return true;
+}
+/* Step 6. */
+jschar c = chars[k];
+/* Step 7. */
+if (c != '%')
+goto step_18;
+/* Step 8. */
+if (k > length - 6)
+goto step_14;
+/* Step 9. */
+if (chars[k + 1] != 'u')
+goto step_14;
+#define ENSURE_BUILDING                             \
+JS_BEGIN_MACRO                                  \
+if (!building) {                            \
+building = true;                        \
+if (!sb.reserve(length))                \
+return false;                       \
+sb.infallibleAppend(chars, chars + k);  \
+}                                           \
+JS_END_MACRO
+/* Step 10-13. */
+if (Unhex4(&chars[k + 2], &c)) {
+ENSURE_BUILDING;
+k += 5;
+goto step_18;
+}
+step_14:
+/* Step 14. */
+if (k > length - 3)
+goto step_18;
+/* Step 15-17. */
+if (Unhex2(&chars[k + 1], &c)) {
+ENSURE_BUILDING;
+k += 2;
+}
+step_18:
+if (building)
+sb.infallibleAppend(c);
+/* Step 19. */
+k += 1;
+}
+#undef ENSURE_BUILDING
+}
+#if JS_HAS_UNEVAL
+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;
+}
+#endif
+static const JSFunctionSpec string_functions[] = {
+JS_FN(js_escape_str,             str_escape,                1,0),
+JS_FN(js_unescape_str,           str_unescape,              1,0),
+#if JS_HAS_UNEVAL
+JS_FN(js_uneval_str,             str_uneval,                1,0),
+#endif
+JS_FN(js_decodeURI_str,          str_decodeURI,             1,0),
+JS_FN(js_encodeURI_str,          str_encodeURI,             1,0),
+JS_FN(js_decodeURIComponent_str, str_decodeURI_Component,   1,0),
+JS_FN(js_encodeURIComponent_str, str_encodeURI_Component,   1,0),
+JS_FS_END
+};
+const jschar      js_empty_ucstr[]  = {0};
+const JSSubString js_EmptySubString = {0, js_empty_ucstr};
+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());
+RootedValue value(cx);
+for (size_t i = 0, length = str->length(); i < length; i++) {
+JSString *str1 = js_NewDependentString(cx, str, i, 1);
+if (!str1)
+return false;
+value.setString(str1);
+if (!JSObject::defineElement(cx, obj, i, value,
+JS_PropertyStub, JS_StrictPropertyStub,
+STRING_ELEMENT_ATTRS))
+{
+return false;
+}
+}
+return true;
+}
+bool
+js::str_resolve(JSContext *cx, HandleObject obj, HandleId id, MutableHandleObject objp)
+{
+if (!JSID_IS_INT(id))
+return true;
+RootedString str(cx, obj->as<StringObject>().unbox());
+int32_t slot = JSID_TO_INT(id);
+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 (!JSObject::defineElement(cx, obj, uint32_t(slot), value, nullptr, nullptr,
+STRING_ELEMENT_ATTRS))
+{
+return false;
+}
+objp.set(obj);
+}
+return true;
+}
+const Class StringObject::class_ = {
+js_String_str,
+JSCLASS_HAS_RESERVED_SLOTS(StringObject::RESERVED_SLOTS) |
+JSCLASS_NEW_RESOLVE | JSCLASS_HAS_CACHED_PROTO(JSProto_String),
+JS_PropertyStub,         /* addProperty */
+JS_DeletePropertyStub,   /* delProperty */
+JS_PropertyStub,         /* getProperty */
+JS_StrictPropertyStub,   /* setProperty */
+str_enumerate,
+(JSResolveOp)str_resolve,
+JS_ConvertStub
+};
+/*
+* Returns a JSString * for the |this| value associated with 'call', or throws
+* a TypeError if |this| is null or undefined.  This algorithm is the same as
+* calling CheckObjectCoercible(this), then returning ToString(this), as all
+* String.prototype.* methods do (other than toString and valueOf).
+*/
+static MOZ_ALWAYS_INLINE JSString *
+ThisToStringForStringProto(JSContext *cx, CallReceiver call)
+{
+JS_CHECK_RECURSION(cx, return nullptr);
+if (call.thisv().isString())
+return call.thisv().toString();
+if (call.thisv().isObject()) {
+RootedObject obj(cx, &call.thisv().toObject());
+if (obj->is<StringObject>()) {
+Rooted<jsid> id(cx, NameToId(cx->names().toString));
+if (ClassMethodIsNative(cx, obj, &StringObject::class_, id, js_str_toString)) {
+JSString *str = obj->as<StringObject>().unbox();
+call.setThis(StringValue(str));
+return str;
+}
+}
+} else if (call.thisv().isNullOrUndefined()) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_CANT_CONVERT_TO,
+call.thisv().isNull() ? "null" : "undefined", "object");
+return nullptr;
+}
+JSString *str = ToStringSlow<CanGC>(cx, call.thisv());
+if (!str)
+return nullptr;
+call.setThis(StringValue(str));
+return str;
+}
+MOZ_ALWAYS_INLINE bool
+IsString(HandleValue v)
+{
+return v.isString() || (v.isObject() && v.toObject().is<StringObject>());
+}
+#if JS_HAS_TOSOURCE
+/*
+* String.prototype.quote is generic (as are most string methods), unlike
+* toSource, toString, and valueOf.
+*/
+static bool
+str_quote(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+str = js_QuoteString(cx, str, '"');
+if (!str)
+return false;
+args.rval().setString(str);
+return true;
+}
+MOZ_ALWAYS_INLINE bool
+str_toSource_impl(JSContext *cx, CallArgs args)
+{
+JS_ASSERT(IsString(args.thisv()));
+Rooted<JSString*> str(cx, ToString<CanGC>(cx, args.thisv()));
+if (!str)
+return false;
+str = js_QuoteString(cx, str, '"');
+if (!str)
+return false;
+StringBuffer sb(cx);
+if (!sb.append("(new String(") || !sb.append(str) || !sb.append("))"))
+return false;
+str = sb.finishString();
+if (!str)
+return false;
+args.rval().setString(str);
+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);
+}
+#endif /* JS_HAS_TOSOURCE */
+MOZ_ALWAYS_INLINE bool
+str_toString_impl(JSContext *cx, CallArgs args)
+{
+JS_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);
+}
+/*
+* Java-like string native methods.
+*/
+static MOZ_ALWAYS_INLINE bool
+ValueToIntegerRange(JSContext *cx, HandleValue v, int32_t *out)
+{
+if (v.isInt32()) {
+*out = v.toInt32();
+} else {
+double d;
+if (!ToInteger(cx, v, &d))
+return false;
+if (d > INT32_MAX)
+*out = INT32_MAX;
+else if (d < INT32_MIN)
+*out = INT32_MIN;
+else
+*out = int32_t(d);
+}
+return true;
+}
+static JSString *
+DoSubstr(JSContext *cx, JSString *str, size_t begin, size_t len)
+{
+/*
+* Optimization for one level deep ropes.
+* This is common for the following pattern:
+*
+* while() {
+*   text = text.substr(0, x) + "bla" + text.substr(x)
+*   test.charCodeAt(x + 1)
+* }
+*/
+if (str->isRope()) {
+JSRope *rope = &str->asRope();
+/* Substring is totally in leftChild of rope. */
+if (begin + len <= rope->leftChild()->length()) {
+str = rope->leftChild();
+return js_NewDependentString(cx, str, begin, len);
+}
+/* Substring is totally in rightChild of rope. */
+if (begin >= rope->leftChild()->length()) {
+str = rope->rightChild();
+begin -= rope->leftChild()->length();
+return js_NewDependentString(cx, str, begin, len);
+}
+/*
+* Requested substring is partly in the left and partly in right child.
+* Create a rope of substrings for both childs.
+*/
+JS_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<JSRope *> ropeRoot(cx, rope);
+RootedString lhs(cx, js_NewDependentString(cx, ropeRoot->leftChild(),
+begin, lhsLength));
+if (!lhs)
+return nullptr;
+RootedString rhs(cx, js_NewDependentString(cx, ropeRoot->rightChild(), 0, rhsLength));
+if (!rhs)
+return nullptr;
+return JSRope::new_<CanGC>(cx, lhs, rhs, len);
+}
+return js_NewDependentString(cx, str, begin, len);
+}
+static bool
+str_substring(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+JSString *str = ThisToStringForStringProto(cx, args);
+if (!str)
+return false;
+int32_t length, begin, end;
+if (args.length() > 0) {
+end = length = int32_t(str->length());
+if (args[0].isInt32()) {
+begin = args[0].toInt32();
+} else {
+RootedString strRoot(cx, str);
+if (!ValueToIntegerRange(cx, args[0], &begin))
+return false;
+str = strRoot;
+}
+if (begin < 0)
+begin = 0;
+else if (begin > length)
+begin = length;
+if (args.hasDefined(1)) {
+if (args[1].isInt32()) {
+end = args[1].toInt32();
+} else {
+RootedString strRoot(cx, str);
+if (!ValueToIntegerRange(cx, args[1], &end))
+return false;
+str = strRoot;
+}
+if (end > length) {
+end = length;
+} else {
+if (end < 0)
+end = 0;
+if (end < begin) {
+int32_t tmp = begin;
+begin = end;
+end = tmp;
+}
+}
+}
+str = DoSubstr(cx, str, size_t(begin), size_t(end - begin));
+if (!str)
+return false;
+}
+args.rval().setString(str);
+return true;
+}
+JSString* JS_FASTCALL
+js_toLowerCase(JSContext *cx, JSString *str)
+{
+size_t n = str->length();
+const jschar *s = str->getChars(cx);
+if (!s)
+return nullptr;
+jschar *news = cx->pod_malloc<jschar>(n + 1);
+if (!news)
+return nullptr;
+for (size_t i = 0; i < n; i++)
+news[i] = unicode::ToLowerCase(s[i]);
+news[n] = 0;
+str = js_NewString<CanGC>(cx, news, n);
+if (!str) {
+js_free(news);
+return nullptr;
+}
+return str;
+}
+static inline bool
+ToLowerCaseHelper(JSContext *cx, CallReceiver call)
+{
+RootedString str(cx, ThisToStringForStringProto(cx, call));
+if (!str)
+return false;
+str = js_toLowerCase(cx, str);
+if (!str)
+return false;
+call.rval().setString(str);
+return true;
+}
+static bool
+str_toLowerCase(JSContext *cx, unsigned argc, Value *vp)
+{
+return ToLowerCaseHelper(cx, CallArgsFromVp(argc, vp));
+}
+static bool
+str_toLocaleLowerCase(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+/*
+* 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) {
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+RootedValue result(cx);
+if (!cx->runtime()->localeCallbacks->localeToLowerCase(cx, str, &result))
+return false;
+args.rval().set(result);
+return true;
+}
+return ToLowerCaseHelper(cx, args);
+}
+JSString* JS_FASTCALL
+js_toUpperCase(JSContext *cx, JSString *str)
+{
+size_t n = str->length();
+const jschar *s = str->getChars(cx);
+if (!s)
+return nullptr;
+jschar *news = cx->pod_malloc<jschar>(n + 1);
+if (!news)
+return nullptr;
+for (size_t i = 0; i < n; i++)
+news[i] = unicode::ToUpperCase(s[i]);
+news[n] = 0;
+str = js_NewString<CanGC>(cx, news, n);
+if (!str) {
+js_free(news);
+return nullptr;
+}
+return str;
+}
+static bool
+ToUpperCaseHelper(JSContext *cx, CallReceiver call)
+{
+RootedString str(cx, ThisToStringForStringProto(cx, call));
+if (!str)
+return false;
+str = js_toUpperCase(cx, str);
+if (!str)
+return false;
+call.rval().setString(str);
+return true;
+}
+static bool
+str_toUpperCase(JSContext *cx, unsigned argc, Value *vp)
+{
+return ToUpperCaseHelper(cx, CallArgsFromVp(argc, vp));
+}
+static bool
+str_toLocaleUpperCase(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+/*
+* 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) {
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+RootedValue result(cx);
+if (!cx->runtime()->localeCallbacks->localeToUpperCase(cx, str, &result))
+return false;
+args.rval().set(result);
+return true;
+}
+return ToUpperCaseHelper(cx, args);
+}
+#if !EXPOSE_INTL_API
+static bool
+str_localeCompare(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+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
+#if EXPOSE_INTL_API
+static const size_t SB_LENGTH = 32;
+/* ES6 20140210 draft 21.1.3.12. */
+static bool
+str_normalize(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+// Steps 1-3.
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+// Step 4.
+UNormalizationMode form;
+if (!args.hasDefined(0)) {
+form = UNORM_NFC;
+} else {
+// Steps 5-6.
+Rooted<JSLinearString*> formStr(cx, ArgToRootedString(cx, args, 0));
+if (!formStr)
+return false;
+// Step 7.
+if (formStr == cx->names().NFC) {
+form = UNORM_NFC;
+} else if (formStr == cx->names().NFD) {
+form = UNORM_NFD;
+} else if (formStr == cx->names().NFKC) {
+form = UNORM_NFKC;
+} else if (formStr == cx->names().NFKD) {
+form = UNORM_NFKD;
+} else {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr,
+JSMSG_INVALID_NORMALIZE_FORM);
+return false;
+}
+}
+// Step 8.
+Rooted<JSFlatString*> flatStr(cx, str->ensureFlat(cx));
+if (!flatStr)
+return false;
+const UChar *srcChars = JSCharToUChar(flatStr->chars());
+int32_t srcLen = SafeCast<int32_t>(flatStr->length());
+StringBuffer chars(cx);
+if (!chars.resize(SB_LENGTH))
+return false;
+UErrorCode status = U_ZERO_ERROR;
+int32_t size = unorm_normalize(srcChars, srcLen, form, 0,
+JSCharToUChar(chars.begin()), SB_LENGTH,
+&status);
+if (status == U_BUFFER_OVERFLOW_ERROR) {
+if (!chars.resize(size))
+return false;
+status = U_ZERO_ERROR;
+#ifdef DEBUG
+int32_t finalSize =
+#endif
+unorm_normalize(srcChars, srcLen, form, 0,
+JSCharToUChar(chars.begin()), size,
+&status);
+MOZ_ASSERT(size == finalSize || U_FAILURE(status), "unorm_normalize behaved inconsistently");
+}
+if (U_FAILURE(status))
+return false;
+// Trim any unused characters.
+if (!chars.resize(size))
+return false;
+RootedString ns(cx, chars.finishString());
+if (!ns)
+return false;
+// Step 9.
+args.rval().setString(ns);
+return true;
+}
+#endif
+bool
+js_str_charAt(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx);
+size_t i;
+if (args.thisv().isString() && args.length() != 0 && args[0].isInt32()) {
+str = args.thisv().toString();
+i = size_t(args[0].toInt32());
+if (i >= str->length())
+goto out_of_range;
+} else {
+str = ThisToStringForStringProto(cx, args);
+if (!str)
+return false;
+double d = 0.0;
+if (args.length() > 0 && !ToInteger(cx, args[0], &d))
+return false;
+if (d < 0 || str->length() <= d)
+goto out_of_range;
+i = size_t(d);
+}
+str = cx->staticStrings().getUnitStringForElement(cx, str, i);
+if (!str)
+return false;
+args.rval().setString(str);
+return true;
+out_of_range:
+args.rval().setString(cx->runtime()->emptyString);
+return true;
+}
+bool
+js_str_charCodeAt(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx);
+size_t i;
+if (args.thisv().isString() && args.length() != 0 && args[0].isInt32()) {
+str = args.thisv().toString();
+i = size_t(args[0].toInt32());
+if (i >= str->length())
+goto out_of_range;
+} else {
+str = ThisToStringForStringProto(cx, args);
+if (!str)
+return false;
+double d = 0.0;
+if (args.length() > 0 && !ToInteger(cx, args[0], &d))
+return false;
+if (d < 0 || str->length() <= d)
+goto out_of_range;
+i = size_t(d);
+}
+jschar c;
+if (!str->getChar(cx, i, &c))
+return false;
+args.rval().setInt32(c);
+return true;
+out_of_range:
+args.rval().setNaN();
+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 */
+int
+js_BoyerMooreHorspool(const jschar *text, uint32_t textlen,
+const jschar *pat, uint32_t patlen)
+{
+uint8_t skip[sBMHCharSetSize];
+JS_ASSERT(0 < patlen && patlen <= sBMHPatLenMax);
+for (uint32_t i = 0; i < sBMHCharSetSize; i++)
+skip[i] = (uint8_t)patlen;
+uint32_t m = patlen - 1;
+for (uint32_t i = 0; i < m; i++) {
+jschar c = pat[i];
+if (c >= sBMHCharSetSize)
+return sBMHBadPattern;
+skip[c] = (uint8_t)(m - i);
+}
+jschar c;
+for (uint32_t k = m;
+k < textlen;
+k += ((c = text[k]) >= sBMHCharSetSize) ? patlen : skip[c]) {
+for (uint32_t i = k, j = m; ; i--, j--) {
+if (text[i] != pat[j])
+break;
+if (j == 0)
+return static_cast<int>(i);  /* safe: max string size */
+}
+}
+return -1;
+}
+struct MemCmp {
+typedef uint32_t Extent;
+static MOZ_ALWAYS_INLINE Extent computeExtent(const jschar *, uint32_t patlen) {
+return (patlen - 1) * sizeof(jschar);
+}
+static MOZ_ALWAYS_INLINE bool match(const jschar *p, const jschar *t, Extent extent) {
+return memcmp(p, t, extent) == 0;
+}
+};
+struct ManualCmp {
+typedef const jschar *Extent;
+static MOZ_ALWAYS_INLINE Extent computeExtent(const jschar *pat, uint32_t patlen) {
+return pat + patlen;
+}
+static MOZ_ALWAYS_INLINE bool match(const jschar *p, const jschar *t, Extent extent) {
+for (; p != extent; ++p, ++t) {
+if (*p != *t)
+return false;
+}
+return true;
+}
+};
+template <class InnerMatch>
+static int
+UnrolledMatch(const jschar *text, uint32_t textlen, const jschar *pat, uint32_t patlen)
+{
+JS_ASSERT(patlen > 0 && textlen > 0);
+const jschar *textend = text + textlen - (patlen - 1);
+const jschar p0 = *pat;
+const jschar *const patNext = pat + 1;
+const typename InnerMatch::Extent extent = InnerMatch::computeExtent(pat, patlen);
+uint8_t fixup;
+const jschar *t = text;
+switch ((textend - t) & 7) {
+case 0: if (*t++ == p0) { fixup = 8; goto match; }
+case 7: if (*t++ == p0) { fixup = 7; goto match; }
+case 6: if (*t++ == p0) { fixup = 6; goto match; }
+case 5: if (*t++ == p0) { fixup = 5; goto match; }
+case 4: if (*t++ == p0) { fixup = 4; goto match; }
+case 3: if (*t++ == p0) { fixup = 3; goto match; }
+case 2: if (*t++ == p0) { fixup = 2; goto match; }
+case 1: if (*t++ == p0) { fixup = 1; goto match; }
+}
+while (t != textend) {
+if (t[0] == p0) { t += 1; fixup = 8; goto match; }
+if (t[1] == p0) { t += 2; fixup = 7; goto match; }
+if (t[2] == p0) { t += 3; fixup = 6; goto match; }
+if (t[3] == p0) { t += 4; fixup = 5; goto match; }
+if (t[4] == p0) { t += 5; fixup = 4; goto match; }
+if (t[5] == p0) { t += 6; fixup = 3; goto match; }
+if (t[6] == p0) { t += 7; fixup = 2; goto match; }
+if (t[7] == p0) { t += 8; fixup = 1; goto match; }
+t += 8;
+continue;
+do {
+if (*t++ == p0) {
+match:
+if (!InnerMatch::match(patNext, t, extent))
+goto failed_match;
+return t - text - 1;
+}
+failed_match:;
+} while (--fixup > 0);
+}
+return -1;
+}
+static MOZ_ALWAYS_INLINE int
+StringMatch(const jschar *text, uint32_t textlen,
+const jschar *pat, uint32_t patlen)
+{
+if (patlen == 0)
+return 0;
+if (textlen < patlen)
+return -1;
+#if defined(__i386__) || defined(_M_IX86) || defined(__i386)
+/*
+* Given enough registers, the unrolled loop below is faster than the
+* following loop. 32-bit x86 does not have enough registers.
+*/
+if (patlen == 1) {
+const jschar p0 = *pat;
+for (const jschar *c = text, *end = text + textlen; c != end; ++c) {
+if (*c == p0)
+return c - text;
+}
+return -1;
+}
+#endif
+/*
+* 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
+* empirically. See bug 526348.
+*/
+if (textlen >= 512 && patlen >= 11 && patlen <= sBMHPatLenMax) {
+int index = js_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.
+*
+* FIXME: Linux memcmp performance is sad and the manual loop is faster.
+*/
+return
+#if !defined(__linux__)
+patlen > 128 ? UnrolledMatch<MemCmp>(text, textlen, pat, patlen)
+:
+#endif
+UnrolledMatch<ManualCmp>(text, textlen, pat, patlen);
+}
+static const size_t sRopeMatchThresholdRatioLog2 = 5;
+bool
+js::StringHasPattern(const jschar *text, uint32_t textlen,
+const jschar *pat, uint32_t patlen)
+{
+return StringMatch(text, textlen, pat, patlen) != -1;
+}
+// When an algorithm does not need a string represented as a single linear
+// array of characters, this range utility may be used to traverse the string a
+// sequence of linear arrays of characters. This avoids flattening ropes.
+class StringSegmentRange
+{
+// If malloc() shows up in any profiles from this vector, we can add a new
+// StackAllocPolicy which stashes a reusable freed-at-gc buffer in the cx.
+AutoStringVector stack;
+Rooted<JSLinearString*> cur;
+bool settle(JSString *str) {
+while (str->isRope()) {
+JSRope &rope = str->asRope();
+if (!stack.append(rope.rightChild()))
+return false;
+str = rope.leftChild();
+}
+cur = &str->asLinear();
+return true;
+}
+public:
+StringSegmentRange(JSContext *cx)
+: stack(cx), cur(cx)
+{}
+MOZ_WARN_UNUSED_RESULT bool init(JSString *str) {
+JS_ASSERT(stack.empty());
+return settle(str);
+}
+bool empty() const {
+return cur == nullptr;
+}
+JSLinearString *front() const {
+JS_ASSERT(!cur->isRope());
+return cur;
+}
+MOZ_WARN_UNUSED_RESULT bool popFront() {
+JS_ASSERT(!empty());
+if (stack.empty()) {
+cur = nullptr;
+return true;
+}
+return settle(stack.popCopy());
+}
+};
+/*
+* 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, JSString *textstr, const jschar *pat, uint32_t patlen, int *match)
+{
+JS_ASSERT(textstr->isRope());
+if (patlen == 0) {
+*match = 0;
+return true;
+}
+if (textstr->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.
+*/
+Vector<JSLinearString *, 16, SystemAllocPolicy> strs;
+/*
+* 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.
+*/
+{
+size_t textstrlen = textstr->length();
+size_t threshold = textstrlen >> sRopeMatchThresholdRatioLog2;
+StringSegmentRange r(cx);
+if (!r.init(textstr))
+return false;
+while (!r.empty()) {
+if (threshold-- == 0 || !strs.append(r.front())) {
+const jschar *chars = textstr->getChars(cx);
+if (!chars)
+return false;
+*match = StringMatch(chars, textstrlen, pat, patlen);
+return true;
+}
+if (!r.popFront())
+return false;
+}
+}
+/* Absolute offset from the beginning of the logical string textstr. */
+int pos = 0;
+for (JSLinearString **outerp = strs.begin(); outerp != strs.end(); ++outerp) {
+/* Try to find a match within 'outer'. */
+JSLinearString *outer = *outerp;
+const jschar *chars = outer->chars();
+size_t len = outer->length();
+int matchResult = StringMatch(chars, len, pat, patlen);
+if (matchResult != -1) {
+/* Matched! */
+*match = pos + matchResult;
+return true;
+}
+/* Try to find a match starting in 'outer' and running into other nodes. */
+const jschar *const text = chars + (patlen > len ? 0 : len - patlen + 1);
+const jschar *const textend = chars + len;
+const jschar p0 = *pat;
+const jschar *const p1 = pat + 1;
+const jschar *const patend = pat + patlen;
+for (const jschar *t = text; t != textend; ) {
+if (*t++ != p0)
+continue;
+JSLinearString **innerp = outerp;
+const jschar *ttend = textend;
+for (const jschar *pp = p1, *tt = t; pp != patend; ++pp, ++tt) {
+while (tt == ttend) {
+if (++innerp == strs.end()) {
+*match = -1;
+return true;
+}
+JSLinearString *inner = *innerp;
+tt = inner->chars();
+ttend = tt + inner->length();
+}
+if (*pp != *tt)
+goto break_continue;
+}
+/* Matched! */
+*match = pos + (t - chars) - 1;  /* -1 because of *t++ above */
+return true;
+break_continue:;
+}
+pos += len;
+}
+*match = -1;
+return true;
+}
+/* ES6 20121026 draft 15.5.4.24. */
+static bool
+str_contains(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+// Steps 1, 2, and 3
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+// Steps 4 and 5
+Rooted<JSLinearString*> searchStr(cx, ArgToRootedString(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(Min(Max(d, 0.0), double(UINT32_MAX)));
+}
+}
+// Step 8
+uint32_t textLen = str->length();
+const jschar *textChars = str->getChars(cx);
+if (!textChars)
+return false;
+// Step 9
+uint32_t start = Min(Max(pos, 0U), textLen);
+// Step 10
+uint32_t searchLen = searchStr->length();
+const jschar *searchChars = searchStr->chars();
+// Step 11
+textChars += start;
+textLen -= start;
+int match = StringMatch(textChars, textLen, searchChars, searchLen);
+args.rval().setBoolean(match != -1);
+return true;
+}
+/* ES6 20120927 draft 15.5.4.7. */
+static bool
+str_indexOf(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+// Steps 1, 2, and 3
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+// Steps 4 and 5
+Rooted<JSLinearString*> searchStr(cx, ArgToRootedString(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(Min(Max(d, 0.0), double(UINT32_MAX)));
+}
+}
+// Step 8
+uint32_t textLen = str->length();
+const jschar *textChars = str->getChars(cx);
+if (!textChars)
+return false;
+// Step 9
+uint32_t start = Min(Max(pos, 0U), textLen);
+// Step 10
+uint32_t searchLen = searchStr->length();
+const jschar *searchChars = searchStr->chars();
+// Step 11
+textChars += start;
+textLen -= start;
+int match = StringMatch(textChars, textLen, searchChars, searchLen);
+args.rval().setInt32((match == -1) ? -1 : start + match);
+return true;
+}
+static bool
+str_lastIndexOf(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString textstr(cx, ThisToStringForStringProto(cx, args));
+if (!textstr)
+return false;
+size_t textlen = textstr->length();
+Rooted<JSLinearString*> patstr(cx, ArgToRootedString(cx, args, 0));
+if (!patstr)
+return false;
+size_t patlen = patstr->length();
+int i = textlen - patlen; // Start searching here
+if (i < 0) {
+args.rval().setInt32(-1);
+return true;
+}
+if (args.length() > 1) {
+if (args[1].isInt32()) {
+int j = args[1].toInt32();
+if (j <= 0)
+i = 0;
+else if (j < i)
+i = j;
+} else {
+double d;
+if (!ToNumber(cx, args[1], &d))
+return false;
+if (!IsNaN(d)) {
+d = ToInteger(d);
+if (d <= 0)
+i = 0;
+else if (d < i)
+i = (int)d;
+}
+}
+}
+if (patlen == 0) {
+args.rval().setInt32(i);
+return true;
+}
+const jschar *text = textstr->getChars(cx);
+if (!text)
+return false;
+const jschar *pat = patstr->chars();
+const jschar *t = text + i;
+const jschar *textend = text - 1;
+const jschar p0 = *pat;
+const jschar *patNext = pat + 1;
+const jschar *patEnd = pat + patlen;
+for (; t != textend; --t) {
+if (*t == p0) {
+const jschar *t1 = t + 1;
+for (const jschar *p1 = patNext; p1 != patEnd; ++p1, ++t1) {
+if (*t1 != *p1)
+goto break_continue;
+}
+args.rval().setInt32(t - text);
+return true;
+}
+break_continue:;
+}
+args.rval().setInt32(-1);
+return true;
+}
+/* ES6 20131108 draft 21.1.3.18. */
+static bool
+str_startsWith(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+// Steps 1, 2, and 3
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+// Step 4
+if (args.get(0).isObject() && IsObjectWithClass(args[0], ESClass_RegExp, cx)) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_INVALID_ARG_TYPE,
+"first", "", "Regular Expression");
+return false;
+}
+// Steps 5 and 6
+Rooted<JSLinearString*> searchStr(cx, ArgToRootedString(cx, args, 0));
+if (!searchStr)
+return false;
+// Steps 7 and 8
+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(Min(Max(d, 0.0), double(UINT32_MAX)));
+}
+}
+// Step 9
+uint32_t textLen = str->length();
+const jschar *textChars = str->getChars(cx);
+if (!textChars)
+return false;
+// Step 10
+uint32_t start = Min(Max(pos, 0U), textLen);
+// Step 11
+uint32_t searchLen = searchStr->length();
+const jschar *searchChars = searchStr->chars();
+// Step 12
+if (searchLen + start < searchLen || searchLen + start > textLen) {
+args.rval().setBoolean(false);
+return true;
+}
+// Steps 13 and 14
+args.rval().setBoolean(PodEqual(textChars + start, searchChars, searchLen));
+return true;
+}
+/* ES6 20131108 draft 21.1.3.7. */
+static bool
+str_endsWith(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+// Steps 1, 2, and 3
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+// Step 4
+if (args.get(0).isObject() && IsObjectWithClass(args[0], ESClass_RegExp, cx)) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_INVALID_ARG_TYPE,
+"first", "", "Regular Expression");
+return false;
+}
+// Steps 5 and 6
+Rooted<JSLinearString *> searchStr(cx, ArgToRootedString(cx, args, 0));
+if (!searchStr)
+return false;
+// Step 7
+uint32_t textLen = str->length();
+const jschar *textChars = str->getChars(cx);
+if (!textChars)
+return false;
+// Steps 8 and 9
+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(Min(Max(d, 0.0), double(UINT32_MAX)));
+}
+}
+// Step 10
+uint32_t end = Min(Max(pos, 0U), textLen);
+// Step 11
+uint32_t searchLen = searchStr->length();
+const jschar *searchChars = searchStr->chars();
+// Step 13 (reordered)
+if (searchLen > end) {
+args.rval().setBoolean(false);
+return true;
+}
+// Step 12
+uint32_t start = end - searchLen;
+// Steps 14 and 15
+args.rval().setBoolean(PodEqual(textChars + start, searchChars, searchLen));
+return true;
+}
+static bool
+js_TrimString(JSContext *cx, Value *vp, bool trimLeft, bool trimRight)
+{
+CallReceiver call = CallReceiverFromVp(vp);
+RootedString str(cx, ThisToStringForStringProto(cx, call));
+if (!str)
+return false;
+size_t length = str->length();
+const jschar *chars = str->getChars(cx);
+if (!chars)
+return false;
+size_t begin = 0;
+size_t end = length;
+if (trimLeft) {
+while (begin < length && unicode::IsSpace(chars[begin]))
+++begin;
+}
+if (trimRight) {
+while (end > begin && unicode::IsSpace(chars[end - 1]))
+--end;
+}
+str = js_NewDependentString(cx, str, begin, end - begin);
+if (!str)
+return false;
+call.rval().setString(str);
+return true;
+}
+static bool
+str_trim(JSContext *cx, unsigned argc, Value *vp)
+{
+return js_TrimString(cx, vp, true, true);
+}
+static bool
+str_trimLeft(JSContext *cx, unsigned argc, Value *vp)
+{
+return js_TrimString(cx, vp, true, false);
+}
+static bool
+str_trimRight(JSContext *cx, unsigned argc, Value *vp)
+{
+return js_TrimString(cx, vp, false, true);
+}
+/*
+* Perl-inspired string functions.
+*/
+namespace {
+/* Result of a successfully performed flat match. */
+class FlatMatch
+{
+RootedAtom patstr;
+const jschar *pat;
+size_t       patlen;
+int32_t      match_;
+friend class StringRegExpGuard;
+public:
+FlatMatch(JSContext *cx) : patstr(cx) {}
+JSLinearString *pattern() const { return patstr; }
+size_t patternLength() const { return patlen; }
+/*
+* Note: The match is -1 when the match is performed successfully,
+* but no match is found.
+*/
+int32_t match() const { return match_; }
+};
+} /* anonymous namespace */
+static inline bool
+IsRegExpMetaChar(jschar c)
+{
+switch (c) {
+/* Taken from the PatternCharacter production in 15.10.1. */
+case '^': case '$': case '\\': case '.': case '*': case '+':
+case '?': case '(': case ')': case '[': case ']': case '{':
+case '}': case '|':
+return true;
+default:
+return false;
+}
+}
+static inline bool
+HasRegExpMetaChars(const jschar *chars, size_t length)
+{
+for (size_t i = 0; i < length; ++i) {
+if (IsRegExpMetaChar(chars[i]))
+return true;
+}
+return false;
+}
+namespace {
+/*
+* StringRegExpGuard factors logic out of String regexp operations.
+*
+* |optarg| indicates in which argument position RegExp flags will be found, if
+* present. This is a Mozilla extension and not part of any ECMA spec.
+*/
+class MOZ_STACK_CLASS StringRegExpGuard
+{
+RegExpGuard re_;
+FlatMatch   fm;
+RootedObject obj_;
+/*
+* Upper bound on the number of characters we are willing to potentially
+* waste on searching for RegExp meta-characters.
+*/
+static const size_t MAX_FLAT_PAT_LEN = 256;
+static JSAtom *
+flattenPattern(JSContext *cx, JSAtom *patstr)
+{
+StringBuffer sb(cx);
+if (!sb.reserve(patstr->length()))
+return nullptr;
+static const jschar ESCAPE_CHAR = '\\';
+const jschar *chars = patstr->chars();
+size_t len = patstr->length();
+for (const jschar *it = chars; it != chars + len; ++it) {
+if (IsRegExpMetaChar(*it)) {
+if (!sb.append(ESCAPE_CHAR) || !sb.append(*it))
+return nullptr;
+} else {
+if (!sb.append(*it))
+return nullptr;
+}
+}
+return sb.finishAtom();
+}
+public:
+StringRegExpGuard(JSContext *cx)
+: re_(cx), fm(cx), obj_(cx)
+{ }
+/* init must succeed in order to call tryFlatMatch or normalizeRegExp. */
+bool init(JSContext *cx, CallArgs args, bool convertVoid = false)
+{
+if (args.length() != 0 && IsObjectWithClass(args[0], ESClass_RegExp, cx))
+return init(cx, &args[0].toObject());
+if (convertVoid && !args.hasDefined(0)) {
+fm.patstr = cx->runtime()->emptyString;
+return true;
+}
+JSString *arg = ArgToRootedString(cx, args, 0);
+if (!arg)
+return false;
+fm.patstr = AtomizeString(cx, arg);
+if (!fm.patstr)
+return false;
+return true;
+}
+bool init(JSContext *cx, JSObject *regexp) {
+obj_ = regexp;
+JS_ASSERT(ObjectClassIs(obj_, ESClass_RegExp, cx));
+if (!RegExpToShared(cx, obj_, &re_))
+return false;
+return true;
+}
+bool init(JSContext *cx, HandleString pattern) {
+fm.patstr = AtomizeString(cx, pattern);
+if (!fm.patstr)
+return false;
+return true;
+}
+/*
+* Attempt to match |patstr| to |textstr|. A flags argument, metachars in
+* the pattern string, or a lengthy pattern string can thwart this process.
+*
+* |checkMetaChars| looks for regexp metachars in the pattern string.
+*
+* Return whether flat matching could be used.
+*
+* N.B. tryFlatMatch returns nullptr on OOM, so the caller must check
+* cx->isExceptionPending().
+*/
+const FlatMatch *
+tryFlatMatch(JSContext *cx, JSString *textstr, unsigned optarg, unsigned argc,
+bool checkMetaChars = true)
+{
+if (re_.initialized())
+return nullptr;
+fm.pat = fm.patstr->chars();
+fm.patlen = fm.patstr->length();
+if (optarg < argc)
+return nullptr;
+if (checkMetaChars &&
+(fm.patlen > MAX_FLAT_PAT_LEN || HasRegExpMetaChars(fm.pat, fm.patlen))) {
+return nullptr;
+}
+/*
+* textstr could be a rope, so we want to avoid flattening it for as
+* long as possible.
+*/
+if (textstr->isRope()) {
+if (!RopeMatch(cx, textstr, fm.pat, fm.patlen, &fm.match_))
+return nullptr;
+} else {
+const jschar *text = textstr->asLinear().chars();
+size_t textlen = textstr->length();
+fm.match_ = StringMatch(text, textlen, fm.pat, fm.patlen);
+}
+return &fm;
+}
+/* If the pattern is not already a regular expression, make it so. */
+bool normalizeRegExp(JSContext *cx, bool flat, unsigned optarg, CallArgs args)
+{
+if (re_.initialized())
+return true;
+/* Build RegExp from pattern string. */
+RootedString opt(cx);
+if (optarg < args.length()) {
+opt = ToString<CanGC>(cx, args[optarg]);
+if (!opt)
+return false;
+} else {
+opt = nullptr;
+}
+Rooted<JSAtom *> patstr(cx);
+if (flat) {
+patstr = flattenPattern(cx, fm.patstr);
+if (!patstr)
+return false;
+} else {
+patstr = fm.patstr;
+}
+JS_ASSERT(patstr);
+return cx->compartment()->regExps.get(cx, patstr, opt, &re_);
+}
+bool zeroLastIndex(JSContext *cx) {
+if (!regExpIsObject())
+return true;
+// Use a fast path for same-global RegExp objects with writable
+// lastIndex.
+if (obj_->is<RegExpObject>() && obj_->nativeLookup(cx, cx->names().lastIndex)->writable()) {
+obj_->as<RegExpObject>().zeroLastIndex();
+return true;
+}
+// Handle everything else generically (including throwing if .lastIndex is non-writable).
+RootedValue zero(cx, Int32Value(0));
+return JSObject::setProperty(cx, obj_, obj_, cx->names().lastIndex, &zero, true);
+}
+RegExpShared &regExp() { return *re_; }
+bool regExpIsObject() { return obj_ != nullptr; }
+HandleObject regExpObject() {
+JS_ASSERT(regExpIsObject());
+return obj_;
+}
+private:
+StringRegExpGuard(const StringRegExpGuard &) MOZ_DELETE;
+void operator=(const StringRegExpGuard &) MOZ_DELETE;
+};
+} /* anonymous namespace */
+static bool
+DoMatchLocal(JSContext *cx, CallArgs args, RegExpStatics *res, Handle<JSLinearString*> input,
+RegExpShared &re)
+{
+size_t charsLen = input->length();
+const jschar *chars = input->chars();
+size_t i = 0;
+ScopedMatchPairs matches(&cx->tempLifoAlloc());
+RegExpRunStatus status = re.execute(cx, chars, charsLen, &i, matches);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success_NotFound) {
+args.rval().setNull();
+return true;
+}
+if (!res->updateFromMatchPairs(cx, input, matches))
+return false;
+RootedValue rval(cx);
+if (!CreateRegExpMatchResult(cx, input, matches, &rval))
+return false;
+args.rval().set(rval);
+return true;
+}
+/* ES5 15.5.4.10 step 8. */
+static bool
+DoMatchGlobal(JSContext *cx, CallArgs args, RegExpStatics *res, Handle<JSLinearString*> input,
+StringRegExpGuard &g)
+{
+// Step 8a.
+//
+// This single zeroing of "lastIndex" covers all "lastIndex" changes in the
+// rest of String.prototype.match, particularly in steps 8f(i) and
+// 8f(iii)(2)(a).  Here's why.
+//
+// The inputs to the calls to RegExp.prototype.exec are a RegExp object
+// whose .global is true and a string.  The only side effect of a call in
+// these circumstances is that the RegExp's .lastIndex will be modified to
+// the next starting index after the discovered match (or to 0 if there's
+// no remaining match).  Because .lastIndex is a non-configurable data
+// property and no script-controllable code executes after step 8a, passing
+// step 8a implies *every* .lastIndex set succeeds.  String.prototype.match
+// calls RegExp.prototype.exec repeatedly, and the last call doesn't match,
+// so the final value of .lastIndex is 0: exactly the state after step 8a
+// succeeds.  No spec step lets script observe intermediate .lastIndex
+// values.
+//
+// The arrays returned by RegExp.prototype.exec always have a string at
+// index 0, for which [[Get]]s have no side effects.
+//
+// Filling in a new array using [[DefineOwnProperty]] is unobservable.
+//
+// This is a tricky point, because after this set, our implementation *can*
+// fail.  The key is that script can't distinguish these failure modes from
+// one where, in spec terms, we fail immediately after step 8a.  That *in
+// reality* we might have done extra matching work, or created a partial
+// results array to return, or hit an interrupt, is irrelevant.  The
+// script can't tell we did any of those things but didn't update
+// .lastIndex.  Thus we can optimize steps 8b onward however we want,
+// including eliminating intermediate .lastIndex sets, as long as we don't
+// add ways for script to observe the intermediate states.
+//
+// In short: it's okay to cheat (by setting .lastIndex to 0, once) because
+// we can't get caught.
+if (!g.zeroLastIndex(cx))
+return false;
+// Step 8b.
+AutoValueVector elements(cx);
+size_t lastSuccessfulStart = 0;
+// The loop variables from steps 8c-e aren't needed, as we use different
+// techniques from the spec to implement step 8f's loop.
+// Step 8f.
+MatchPair match;
+size_t charsLen = input->length();
+const jschar *chars = input->chars();
+RegExpShared &re = g.regExp();
+for (size_t searchIndex = 0; searchIndex <= charsLen; ) {
+if (!CheckForInterrupt(cx))
+return false;
+// Steps 8f(i-ii), minus "lastIndex" updates (see above).
+size_t nextSearchIndex = searchIndex;
+RegExpRunStatus status = re.executeMatchOnly(cx, chars, charsLen, &nextSearchIndex, match);
+if (status == RegExpRunStatus_Error)
+return false;
+// Step 8f(ii).
+if (status == RegExpRunStatus_Success_NotFound)
+break;
+lastSuccessfulStart = searchIndex;
+// Steps 8f(iii)(1-3).
+searchIndex = match.isEmpty() ? nextSearchIndex + 1 : nextSearchIndex;
+// Step 8f(iii)(4-5).
+JSLinearString *str = js_NewDependentString(cx, input, match.start, match.length());
+if (!str)
+return false;
+if (!elements.append(StringValue(str)))
+return false;
+}
+// Step 8g.
+if (elements.empty()) {
+args.rval().setNull();
+return true;
+}
+// The last *successful* match updates the RegExpStatics. (Interestingly,
+// this implies that String.prototype.match's semantics aren't those
+// implied by the RegExp.prototype.exec calls in the ES5 algorithm.)
+res->updateLazily(cx, input, &re, lastSuccessfulStart);
+// Steps 8b, 8f(iii)(5-6), 8h.
+JSObject *array = NewDenseCopiedArray(cx, elements.length(), elements.begin());
+if (!array)
+return false;
+args.rval().setObject(*array);
+return true;
+}
+static bool
+BuildFlatMatchArray(JSContext *cx, HandleString textstr, const FlatMatch &fm, CallArgs *args)
+{
+if (fm.match() < 0) {
+args->rval().setNull();
+return true;
+}
+/* For this non-global match, produce a RegExp.exec-style array. */
+RootedObject obj(cx, NewDenseEmptyArray(cx));
+if (!obj)
+return false;
+RootedValue patternVal(cx, StringValue(fm.pattern()));
+RootedValue matchVal(cx, Int32Value(fm.match()));
+RootedValue textVal(cx, StringValue(textstr));
+if (!JSObject::defineElement(cx, obj, 0, patternVal) ||
+!JSObject::defineProperty(cx, obj, cx->names().index, matchVal) ||
+!JSObject::defineProperty(cx, obj, cx->names().input, textVal))
+{
+return false;
+}
+args->rval().setObject(*obj);
+return true;
+}
+/* ES5 15.5.4.10. */
+bool
+js::str_match(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+/* Steps 1-2. */
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+/* Steps 3-4, plus the trailing-argument "flags" extension. */
+StringRegExpGuard g(cx);
+if (!g.init(cx, args, true))
+return false;
+/* Fast path when the search pattern can be searched for as a string. */
+if (const FlatMatch *fm = g.tryFlatMatch(cx, str, 1, args.length()))
+return BuildFlatMatchArray(cx, str, *fm, &args);
+/* Return if there was an error in tryFlatMatch. */
+if (cx->isExceptionPending())
+return false;
+/* Create regular-expression internals as needed to perform the match. */
+if (!g.normalizeRegExp(cx, false, 1, args))
+return false;
+RegExpStatics *res = cx->global()->getRegExpStatics();
+Rooted<JSLinearString*> linearStr(cx, str->ensureLinear(cx));
+if (!linearStr)
+return false;
+/* Steps 5-6, 7. */
+if (!g.regExp().global())
+return DoMatchLocal(cx, args, res, linearStr, g.regExp());
+/* Steps 6, 8. */
+return DoMatchGlobal(cx, args, res, linearStr, g);
+}
+bool
+js::str_search(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+StringRegExpGuard g(cx);
+if (!g.init(cx, args, true))
+return false;
+if (const FlatMatch *fm = g.tryFlatMatch(cx, str, 1, args.length())) {
+args.rval().setInt32(fm->match());
+return true;
+}
+if (cx->isExceptionPending())  /* from tryFlatMatch */
+return false;
+if (!g.normalizeRegExp(cx, false, 1, args))
+return false;
+Rooted<JSLinearString*> linearStr(cx, str->ensureLinear(cx));
+if (!linearStr)
+return false;
+const jschar *chars = linearStr->chars();
+size_t length = linearStr->length();
+RegExpStatics *res = cx->global()->getRegExpStatics();
+/* Per ECMAv5 15.5.4.12 (5) The last index property is ignored and left unchanged. */
+size_t i = 0;
+MatchPair match;
+RegExpRunStatus status = g.regExp().executeMatchOnly(cx, chars, length, &i, match);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success)
+res->updateLazily(cx, linearStr, &g.regExp(), 0);
+JS_ASSERT_IF(status == RegExpRunStatus_Success_NotFound, match.start == -1);
+args.rval().setInt32(match.start);
+return true;
+}
+// Utility for building a rope (lazy concatenation) of strings.
+class RopeBuilder {
+JSContext *cx;
+RootedString res;
+RopeBuilder(const RopeBuilder &other) MOZ_DELETE;
+void operator=(const RopeBuilder &other) MOZ_DELETE;
+public:
+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 {
+struct ReplaceData
+{
+ReplaceData(JSContext *cx)
+: str(cx), g(cx), lambda(cx), elembase(cx), repstr(cx),
+fig(cx, NullValue()), sb(cx)
+{}
+inline void setReplacementString(JSLinearString *string) {
+JS_ASSERT(string);
+lambda = nullptr;
+elembase = nullptr;
+repstr = string;
+/* We're about to store pointers into the middle of our string. */
+dollarEnd = repstr->chars() + repstr->length();
+dollar = js_strchr_limit(repstr->chars(), '$', dollarEnd);
+}
+inline void setReplacementFunction(JSObject *func) {
+JS_ASSERT(func);
+lambda = func;
+elembase = nullptr;
+repstr = nullptr;
+dollar = dollarEnd = nullptr;
+}
+RootedString       str;            /* 'this' parameter object as a string */
+StringRegExpGuard  g;              /* regexp parameter object and private data */
+RootedObject       lambda;         /* replacement function object or null */
+RootedObject       elembase;       /* object for function(a){return b[a]} replace */
+Rooted<JSLinearString*> repstr; /* replacement string */
+const jschar       *dollar;        /* null or pointer to first $ in repstr */
+const jschar       *dollarEnd;     /* limit pointer for js_strchr_limit */
+int                leftIndex;      /* left context index in str->chars */
+JSSubString        dollarStr;      /* for "$$" InterpretDollar result */
+bool               calledBack;     /* record whether callback has been called */
+FastInvokeGuard    fig;            /* used for lambda calls, also holds arguments */
+StringBuffer       sb;             /* buffer built during DoMatch */
+};
+} /* anonymous namespace */
+static bool
+ReplaceRegExp(JSContext *cx, RegExpStatics *res, ReplaceData &rdata);
+static bool
+DoMatchForReplaceLocal(JSContext *cx, RegExpStatics *res, Handle<JSLinearString*> linearStr,
+RegExpShared &re, ReplaceData &rdata)
+{
+size_t charsLen = linearStr->length();
+size_t i = 0;
+ScopedMatchPairs matches(&cx->tempLifoAlloc());
+RegExpRunStatus status = re.execute(cx, linearStr->chars(), charsLen, &i, matches);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success_NotFound)
+return true;
+if (!res->updateFromMatchPairs(cx, linearStr, matches))
+return false;
+return ReplaceRegExp(cx, res, rdata);
+}
+static bool
+DoMatchForReplaceGlobal(JSContext *cx, RegExpStatics *res, Handle<JSLinearString*> linearStr,
+RegExpShared &re, ReplaceData &rdata)
+{
+size_t charsLen = linearStr->length();
+ScopedMatchPairs matches(&cx->tempLifoAlloc());
+for (size_t count = 0, i = 0; i <= charsLen; ++count) {
+if (!CheckForInterrupt(cx))
+return false;
+RegExpRunStatus status = re.execute(cx, linearStr->chars(), charsLen, &i, matches);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success_NotFound)
+break;
+if (!res->updateFromMatchPairs(cx, linearStr, matches))
+return false;
+if (!ReplaceRegExp(cx, res, rdata))
+return false;
+if (!res->matched())
+++i;
+}
+return true;
+}
+static bool
+InterpretDollar(RegExpStatics *res, const jschar *dp, const jschar *ep,
+ReplaceData &rdata, JSSubString *out, size_t *skip)
+{
+JS_ASSERT(*dp == '$');
+/* If there is only a dollar, bail now */
+if (dp + 1 >= ep)
+return false;
+/* Interpret all Perl match-induced dollar variables. */
+jschar dc = dp[1];
+if (JS7_ISDEC(dc)) {
+/* ECMA-262 Edition 3: 1-9 or 01-99 */
+unsigned num = JS7_UNDEC(dc);
+if (num > res->getMatches().parenCount())
+return false;
+const jschar *cp = dp + 2;
+if (cp < ep && (dc = *cp, JS7_ISDEC(dc))) {
+unsigned tmp = 10 * num + JS7_UNDEC(dc);
+if (tmp <= res->getMatches().parenCount()) {
+cp++;
+num = tmp;
+}
+}
+if (num == 0)
+return false;
+*skip = cp - dp;
+JS_ASSERT(num <= res->getMatches().parenCount());
+/*
+* Note: we index to get the paren with the (1-indexed) pair
+* number, as opposed to a (0-indexed) paren number.
+*/
+res->getParen(num, out);
+return true;
+}
+*skip = 2;
+switch (dc) {
+case '$':
+rdata.dollarStr.chars = dp;
+rdata.dollarStr.length = 1;
+*out = rdata.dollarStr;
+return true;
+case '&':
+res->getLastMatch(out);
+return true;
+case '+':
+res->getLastParen(out);
+return true;
+case '`':
+res->getLeftContext(out);
+return true;
+case '\'':
+res->getRightContext(out);
+return true;
+}
+return false;
+}
+static bool
+FindReplaceLength(JSContext *cx, RegExpStatics *res, ReplaceData &rdata, size_t *sizep)
+{
+if (rdata.elembase) {
+/*
+* The base object is used when replace was passed a lambda which looks like
+* 'function(a) { return b[a]; }' for the base object b.  b will not change
+* in the course of the replace unless we end up making a scripted call due
+* to accessing a scripted getter or a value with a scripted toString.
+*/
+JS_ASSERT(rdata.lambda);
+JS_ASSERT(!rdata.elembase->getOps()->lookupProperty);
+JS_ASSERT(!rdata.elembase->getOps()->getProperty);
+RootedValue match(cx);
+if (!res->createLastMatch(cx, &match))
+return false;
+JSAtom *atom = ToAtom<CanGC>(cx, match);
+if (!atom)
+return false;
+RootedValue v(cx);
+if (HasDataProperty(cx, rdata.elembase, AtomToId(atom), v.address()) && v.isString()) {
+rdata.repstr = v.toString()->ensureLinear(cx);
+if (!rdata.repstr)
+return false;
+*sizep = rdata.repstr->length();
+return true;
+}
+/*
+* Couldn't handle this property, fall through and despecialize to the
+* general lambda case.
+*/
+rdata.elembase = nullptr;
+}
+if (rdata.lambda) {
+RootedObject lambda(cx, rdata.lambda);
+PreserveRegExpStatics staticsGuard(cx, res);
+if (!staticsGuard.init(cx))
+return false;
+/*
+* In the lambda case, not only do we find the replacement string's
+* length, we compute repstr and return it via rdata for use within
+* DoReplace.  The lambda is called with arguments ($&, $1, $2, ...,
+* index, input), i.e., all the properties of a regexp match array.
+* For $&, etc., we must create string jsvals from cx->regExpStatics.
+* We grab up stack space to keep the newborn strings GC-rooted.
+*/
+unsigned p = res->getMatches().parenCount();
+unsigned argc = 1 + p + 2;
+InvokeArgs &args = rdata.fig.args();
+if (!args.init(argc))
+return false;
+args.setCallee(ObjectValue(*lambda));
+args.setThis(UndefinedValue());
+/* Push $&, $1, $2, ... */
+unsigned argi = 0;
+if (!res->createLastMatch(cx, args[argi++]))
+return false;
+for (size_t i = 0; i < res->getMatches().parenCount(); ++i) {
+if (!res->createParen(cx, i + 1, args[argi++]))
+return false;
+}
+/* Push match index and input string. */
+args[argi++].setInt32(res->getMatches()[0].start);
+args[argi].setString(rdata.str);
+if (!rdata.fig.invoke(cx))
+return false;
+/* root repstr: rdata is on the stack, so scanned by conservative gc. */
+JSString *repstr = ToString<CanGC>(cx, args.rval());
+if (!repstr)
+return false;
+rdata.repstr = repstr->ensureLinear(cx);
+if (!rdata.repstr)
+return false;
+*sizep = rdata.repstr->length();
+return true;
+}
+JSString *repstr = rdata.repstr;
+CheckedInt<uint32_t> replen = repstr->length();
+for (const jschar *dp = rdata.dollar, *ep = rdata.dollarEnd; dp;
+dp = js_strchr_limit(dp, '$', ep)) {
+JSSubString sub;
+size_t skip;
+if (InterpretDollar(res, dp, ep, rdata, &sub, &skip)) {
+if (sub.length > skip)
+replen += sub.length - skip;
+else
+replen -= skip - sub.length;
+dp += skip;
+} else {
+dp++;
+}
+}
+if (!replen.isValid()) {
+js_ReportAllocationOverflow(cx);
+return false;
+}
+*sizep = replen.value();
+return true;
+}
+/*
+* Precondition: |rdata.sb| already has necessary growth space reserved (as
+* derived from FindReplaceLength).
+*/
+static void
+DoReplace(RegExpStatics *res, ReplaceData &rdata)
+{
+JSLinearString *repstr = rdata.repstr;
+const jschar *cp;
+const jschar *bp = cp = repstr->chars();
+const jschar *dp = rdata.dollar;
+const jschar *ep = rdata.dollarEnd;
+for (; dp; dp = js_strchr_limit(dp, '$', ep)) {
+/* Move one of the constant portions of the replacement value. */
+size_t len = dp - cp;
+rdata.sb.infallibleAppend(cp, len);
+cp = dp;
+JSSubString sub;
+size_t skip;
+if (InterpretDollar(res, dp, ep, rdata, &sub, &skip)) {
+len = sub.length;
+rdata.sb.infallibleAppend(sub.chars, len);
+cp += skip;
+dp += skip;
+} else {
+dp++;
+}
+}
+rdata.sb.infallibleAppend(cp, repstr->length() - (cp - bp));
+}
+static bool
+ReplaceRegExp(JSContext *cx, RegExpStatics *res, ReplaceData &rdata)
+{
+const MatchPair &match = res->getMatches()[0];
+JS_ASSERT(!match.isUndefined());
+JS_ASSERT(match.limit >= match.start && match.limit >= 0);
+rdata.calledBack = true;
+size_t leftoff = rdata.leftIndex;
+size_t leftlen = match.start - leftoff;
+rdata.leftIndex = match.limit;
+size_t replen = 0;  /* silence 'unused' warning */
+if (!FindReplaceLength(cx, res, rdata, &replen))
+return false;
+CheckedInt<uint32_t> newlen(rdata.sb.length());
+newlen += leftlen;
+newlen += replen;
+if (!newlen.isValid()) {
+js_ReportAllocationOverflow(cx);
+return false;
+}
+if (!rdata.sb.reserve(newlen.value()))
+return false;
+JSLinearString &str = rdata.str->asLinear();  /* flattened for regexp */
+const jschar *left = str.chars() + leftoff;
+rdata.sb.infallibleAppend(left, leftlen); /* skipped-over portion of the search value */
+DoReplace(res, rdata);
+return true;
+}
+static bool
+BuildFlatReplacement(JSContext *cx, HandleString textstr, HandleString repstr,
+const FlatMatch &fm, MutableHandleValue rval)
+{
+RopeBuilder builder(cx);
+size_t match = fm.match();
+size_t matchEnd = match + fm.patternLength();
+if (textstr->isRope()) {
+/*
+* 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 false;
+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, js_NewDependentString(cx, str, 0, match - pos));
+if (!leftSide ||
+!builder.append(leftSide) ||
+!builder.append(repstr)) {
+return false;
+}
+}
+/*
+* If str runs off the end of the matched string, append the
+* last part of str.
+*/
+if (strEnd > matchEnd) {
+RootedString rightSide(cx, js_NewDependentString(cx, str, matchEnd - pos,
+strEnd - matchEnd));
+if (!rightSide || !builder.append(rightSide))
+return false;
+}
+} else {
+if (!builder.append(str))
+return false;
+}
+pos += str->length();
+if (!r.popFront())
+return false;
+}
+} else {
+RootedString leftSide(cx, js_NewDependentString(cx, textstr, 0, match));
+if (!leftSide)
+return false;
+RootedString rightSide(cx);
+rightSide = js_NewDependentString(cx, textstr, match + fm.patternLength(),
+textstr->length() - match - fm.patternLength());
+if (!rightSide ||
+!builder.append(leftSide) ||
+!builder.append(repstr) ||
+!builder.append(rightSide)) {
+return false;
+}
+}
+rval.setString(builder.result());
+return true;
+}
+/*
+* Perform a linear-scan dollar substitution on the replacement text,
+* constructing a result string that looks like:
+*
+*      newstring = string[:matchStart] + dollarSub(replaceValue) + string[matchLimit:]
+*/
+static inline bool
+BuildDollarReplacement(JSContext *cx, JSString *textstrArg, JSLinearString *repstr,
+const jschar *firstDollar, const FlatMatch &fm, MutableHandleValue rval)
+{
+Rooted<JSLinearString*> textstr(cx, textstrArg->ensureLinear(cx));
+if (!textstr)
+return false;
+JS_ASSERT(repstr->chars() <= firstDollar && firstDollar < repstr->chars() + repstr->length());
+size_t matchStart = fm.match();
+size_t matchLimit = matchStart + fm.patternLength();
+/*
+* Most probably:
+*
+*      len(newstr) >= len(orig) - len(match) + len(replacement)
+*
+* Note that dollar vars _could_ make the resulting text smaller than this.
+*/
+StringBuffer newReplaceChars(cx);
+if (!newReplaceChars.reserve(textstr->length() - fm.patternLength() + repstr->length()))
+return false;
+/* Move the pre-dollar chunk in bulk. */
+newReplaceChars.infallibleAppend(repstr->chars(), firstDollar);
+/* Move the rest char-by-char, interpreting dollars as we encounter them. */
+#define ENSURE(__cond) if (!(__cond)) return false;
+const jschar *repstrLimit = repstr->chars() + repstr->length();
+for (const jschar *it = firstDollar; it < repstrLimit; ++it) {
+if (*it != '$' || it == repstrLimit - 1) {
+ENSURE(newReplaceChars.append(*it));
+continue;
+}
+switch (*(it + 1)) {
+case '$': /* Eat one of the dollars. */
+ENSURE(newReplaceChars.append(*it));
+break;
+case '&':
+ENSURE(newReplaceChars.append(textstr->chars() + matchStart,
+textstr->chars() + matchLimit));
+break;
+case '`':
+ENSURE(newReplaceChars.append(textstr->chars(), textstr->chars() + matchStart));
+break;
+case '\'':
+ENSURE(newReplaceChars.append(textstr->chars() + matchLimit,
+textstr->chars() + textstr->length()));
+break;
+default: /* The dollar we saw was not special (no matter what its mother told it). */
+ENSURE(newReplaceChars.append(*it));
+continue;
+}
+++it; /* We always eat an extra char in the above switch. */
+}
+RootedString leftSide(cx, js_NewDependentString(cx, textstr, 0, matchStart));
+ENSURE(leftSide);
+RootedString newReplace(cx, newReplaceChars.finishString());
+ENSURE(newReplace);
+JS_ASSERT(textstr->length() >= matchLimit);
+RootedString rightSide(cx, js_NewDependentString(cx, textstr, matchLimit,
+textstr->length() - matchLimit));
+ENSURE(rightSide);
+RopeBuilder builder(cx);
+ENSURE(builder.append(leftSide) &&
+builder.append(newReplace) &&
+builder.append(rightSide));
+#undef ENSURE
+rval.setString(builder.result());
+return true;
+}
+struct StringRange
+{
+size_t start;
+size_t length;
+StringRange(size_t s, size_t l)
+: start(s), length(l)
+{ }
+};
+static inline JSFatInlineString *
+FlattenSubstrings(JSContext *cx, const jschar *chars,
+const StringRange *ranges, size_t rangesLen, size_t outputLen)
+{
+JS_ASSERT(JSFatInlineString::lengthFits(outputLen));
+JSFatInlineString *str = js_NewGCFatInlineString<CanGC>(cx);
+if (!str)
+return nullptr;
+jschar *buf = str->init(outputLen);
+size_t pos = 0;
+for (size_t i = 0; i < rangesLen; i++) {
+PodCopy(buf + pos, chars + ranges[i].start, ranges[i].length);
+pos += ranges[i].length;
+}
+JS_ASSERT(pos == outputLen);
+buf[outputLen] = 0;
+return str;
+}
+static JSString *
+AppendSubstrings(JSContext *cx, Handle<JSFlatString*> flatStr,
+const StringRange *ranges, size_t rangesLen)
+{
+JS_ASSERT(rangesLen);
+/* For single substrings, construct a dependent string. */
+if (rangesLen == 1)
+return js_NewDependentString(cx, flatStr, ranges[0].start, ranges[0].length);
+const jschar *chars = flatStr->getChars(cx);
+if (!chars)
+return nullptr;
+/* Collect substrings into a rope */
+size_t i = 0;
+RopeBuilder rope(cx);
+RootedString part(cx, nullptr);
+while (i < rangesLen) {
+/* Find maximum range that fits in JSFatInlineString */
+size_t substrLen = 0;
+size_t end = i;
+for (; end < rangesLen; end++) {
+if (substrLen + ranges[end].length > JSFatInlineString::MAX_FAT_INLINE_LENGTH)
+break;
+substrLen += ranges[end].length;
+}
+if (i == end) {
+/* Not even one range fits JSFatInlineString, use DependentString */
+const StringRange &sr = ranges[i++];
+part = js_NewDependentString(cx, flatStr, sr.start, sr.length);
+} else {
+/* Copy the ranges (linearly) into a JSFatInlineString */
+part = FlattenSubstrings(cx, chars, ranges + i, end - i, substrLen);
+i = end;
+}
+if (!part)
+return nullptr;
+/* Appending to the rope permanently roots the substring. */
+if (!rope.append(part))
+return nullptr;
+}
+return rope.result();
+}
+static bool
+StrReplaceRegexpRemove(JSContext *cx, HandleString str, RegExpShared &re, MutableHandleValue rval)
+{
+Rooted<JSFlatString*> flatStr(cx, str->ensureFlat(cx));
+if (!flatStr)
+return false;
+Vector<StringRange, 16, SystemAllocPolicy> ranges;
+size_t charsLen = flatStr->length();
+MatchPair match;
+size_t startIndex = 0; /* Index used for iterating through the string. */
+size_t lastIndex = 0;  /* Index after last successful match. */
+size_t lazyIndex = 0;  /* Index before last successful match. */
+/* Accumulate StringRanges for unmatched substrings. */
+while (startIndex <= charsLen) {
+if (!CheckForInterrupt(cx))
+return false;
+RegExpRunStatus status =
+re.executeMatchOnly(cx, flatStr->chars(), charsLen, &startIndex, match);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success_NotFound)
+break;
+/* Include the latest unmatched substring. */
+if (size_t(match.start) > lastIndex) {
+if (!ranges.append(StringRange(lastIndex, match.start - lastIndex)))
+return false;
+}
+lazyIndex = lastIndex;
+lastIndex = startIndex;
+if (match.isEmpty())
+startIndex++;
+/* Non-global removal executes at most once. */
+if (!re.global())
+break;
+}
+/* If unmatched, return the input string. */
+if (!lastIndex) {
+if (startIndex > 0)
+cx->global()->getRegExpStatics()->updateLazily(cx, flatStr, &re, lazyIndex);
+rval.setString(str);
+return true;
+}
+/* The last successful match updates the RegExpStatics. */
+cx->global()->getRegExpStatics()->updateLazily(cx, flatStr, &re, lazyIndex);
+/* Include any remaining part of the string. */
+if (lastIndex < charsLen) {
+if (!ranges.append(StringRange(lastIndex, charsLen - lastIndex)))
+return false;
+}
+/* Handle the empty string before calling .begin(). */
+if (ranges.empty()) {
+rval.setString(cx->runtime()->emptyString);
+return true;
+}
+JSString *result = AppendSubstrings(cx, flatStr, ranges.begin(), ranges.length());
+if (!result)
+return false;
+rval.setString(result);
+return true;
+}
+static inline bool
+StrReplaceRegExp(JSContext *cx, ReplaceData &rdata, MutableHandleValue rval)
+{
+rdata.leftIndex = 0;
+rdata.calledBack = false;
+RegExpStatics *res = cx->global()->getRegExpStatics();
+RegExpShared &re = rdata.g.regExp();
+// The spec doesn't describe this function very clearly, so we go ahead and
+// assume that when the input to String.prototype.replace is a global
+// RegExp, calling the replacer function (assuming one was provided) takes
+// place only after the matching is done. See the comment at the beginning
+// of DoMatchGlobal explaining why we can zero the the RegExp object's
+// lastIndex property here.
+if (re.global() && !rdata.g.zeroLastIndex(cx))
+return false;
+/* Optimize removal. */
+if (rdata.repstr && rdata.repstr->length() == 0) {
+JS_ASSERT(!rdata.lambda && !rdata.elembase && !rdata.dollar);
+return StrReplaceRegexpRemove(cx, rdata.str, re, rval);
+}
+Rooted<JSLinearString*> linearStr(cx, rdata.str->ensureLinear(cx));
+if (!linearStr)
+return false;
+if (re.global()) {
+if (!DoMatchForReplaceGlobal(cx, res, linearStr, re, rdata))
+return false;
+} else {
+if (!DoMatchForReplaceLocal(cx, res, linearStr, re, rdata))
+return false;
+}
+if (!rdata.calledBack) {
+/* Didn't match, so the string is unmodified. */
+rval.setString(rdata.str);
+return true;
+}
+JSSubString sub;
+res->getRightContext(&sub);
+if (!rdata.sb.append(sub.chars, sub.length))
+return false;
+JSString *retstr = rdata.sb.finishString();
+if (!retstr)
+return false;
+rval.setString(retstr);
+return true;
+}
+static inline bool
+str_replace_regexp(JSContext *cx, CallArgs args, ReplaceData &rdata)
+{
+if (!rdata.g.normalizeRegExp(cx, true, 2, args))
+return false;
+return StrReplaceRegExp(cx, rdata, args.rval());
+}
+bool
+js::str_replace_regexp_raw(JSContext *cx, HandleString string, HandleObject regexp,
+HandleString replacement, MutableHandleValue rval)
+{
+/* Optimize removal, so we don't have to create ReplaceData */
+if (replacement->length() == 0) {
+StringRegExpGuard guard(cx);
+if (!guard.init(cx, regexp))
+return false;
+RegExpShared &re = guard.regExp();
+return StrReplaceRegexpRemove(cx, string, re, rval);
+}
+ReplaceData rdata(cx);
+rdata.str = string;
+JSLinearString *repl = replacement->ensureLinear(cx);
+if (!repl)
+return false;
+rdata.setReplacementString(repl);
+if (!rdata.g.init(cx, regexp))
+return false;
+return StrReplaceRegExp(cx, rdata, rval);
+}
+static inline bool
+StrReplaceString(JSContext *cx, ReplaceData &rdata, const FlatMatch &fm, MutableHandleValue rval)
+{
+/*
+* Note: we could optimize the text.length == pattern.length case if we wanted,
+* even in the presence of dollar metachars.
+*/
+if (rdata.dollar)
+return BuildDollarReplacement(cx, rdata.str, rdata.repstr, rdata.dollar, fm, rval);
+return BuildFlatReplacement(cx, rdata.str, rdata.repstr, fm, rval);
+}
+static const uint32_t ReplaceOptArg = 2;
+bool
+js::str_replace_string_raw(JSContext *cx, HandleString string, HandleString pattern,
+HandleString replacement, MutableHandleValue rval)
+{
+ReplaceData rdata(cx);
+rdata.str = string;
+JSLinearString *repl = replacement->ensureLinear(cx);
+if (!repl)
+return false;
+rdata.setReplacementString(repl);
+if (!rdata.g.init(cx, pattern))
+return false;
+const FlatMatch *fm = rdata.g.tryFlatMatch(cx, rdata.str, ReplaceOptArg, ReplaceOptArg, false);
+if (fm->match() < 0) {
+rval.setString(string);
+return true;
+}
+return StrReplaceString(cx, rdata, *fm, rval);
+}
+static inline bool
+str_replace_flat_lambda(JSContext *cx, CallArgs outerArgs, ReplaceData &rdata, const FlatMatch &fm)
+{
+RootedString matchStr(cx, js_NewDependentString(cx, rdata.str, fm.match(), fm.patternLength()));
+if (!matchStr)
+return false;
+/* lambda(matchStr, matchStart, textstr) */
+static const uint32_t lambdaArgc = 3;
+if (!rdata.fig.args().init(lambdaArgc))
+return false;
+CallArgs &args = rdata.fig.args();
+args.setCallee(ObjectValue(*rdata.lambda));
+args.setThis(UndefinedValue());
+Value *sp = args.array();
+sp[0].setString(matchStr);
+sp[1].setInt32(fm.match());
+sp[2].setString(rdata.str);
+if (!rdata.fig.invoke(cx))
+return false;
+RootedString repstr(cx, ToString<CanGC>(cx, args.rval()));
+if (!repstr)
+return false;
+RootedString leftSide(cx, js_NewDependentString(cx, rdata.str, 0, fm.match()));
+if (!leftSide)
+return false;
+size_t matchLimit = fm.match() + fm.patternLength();
+RootedString rightSide(cx, js_NewDependentString(cx, rdata.str, matchLimit,
+rdata.str->length() - matchLimit));
+if (!rightSide)
+return false;
+RopeBuilder builder(cx);
+if (!(builder.append(leftSide) &&
+builder.append(repstr) &&
+builder.append(rightSide))) {
+return false;
+}
+outerArgs.rval().setString(builder.result());
+return true;
+}
+/*
+* Pattern match the script to check if it is is indexing into a particular
+* object, e.g. 'function(a) { return b[a]; }'. Avoid calling the script in
+* such cases, which are used by javascript packers (particularly the popular
+* Dean Edwards packer) to efficiently encode large scripts. We only handle the
+* code patterns generated by such packers here.
+*/
+static bool
+LambdaIsGetElem(JSContext *cx, JSObject &lambda, MutableHandleObject pobj)
+{
+if (!lambda.is<JSFunction>())
+return true;
+RootedFunction fun(cx, &lambda.as<JSFunction>());
+if (!fun->isInterpreted())
+return true;
+JSScript *script = fun->getOrCreateScript(cx);
+if (!script)
+return false;
+jsbytecode *pc = script->code();
+/*
+* JSOP_GETALIASEDVAR tells us exactly where to find the base object 'b'.
+* Rule out the (unlikely) possibility of a heavyweight function since it
+* would make our scope walk off by 1.
+*/
+if (JSOp(*pc) != JSOP_GETALIASEDVAR || fun->isHeavyweight())
+return true;
+ScopeCoordinate sc(pc);
+ScopeObject *scope = &fun->environment()->as<ScopeObject>();
+for (unsigned i = 0; i < sc.hops(); ++i)
+scope = &scope->enclosingScope().as<ScopeObject>();
+Value b = scope->aliasedVar(sc);
+pc += JSOP_GETALIASEDVAR_LENGTH;
+/* Look for 'a' to be the lambda's first argument. */
+if (JSOp(*pc) != JSOP_GETARG || GET_ARGNO(pc) != 0)
+return true;
+pc += JSOP_GETARG_LENGTH;
+/* 'b[a]' */
+if (JSOp(*pc) != JSOP_GETELEM)
+return true;
+pc += JSOP_GETELEM_LENGTH;
+/* 'return b[a]' */
+if (JSOp(*pc) != JSOP_RETURN)
+return true;
+/* 'b' must behave like a normal object. */
+if (!b.isObject())
+return true;
+JSObject &bobj = b.toObject();
+const Class *clasp = bobj.getClass();
+if (!clasp->isNative() || clasp->ops.lookupProperty || clasp->ops.getProperty)
+return true;
+pobj.set(&bobj);
+return true;
+}
+bool
+js::str_replace(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+ReplaceData rdata(cx);
+rdata.str = ThisToStringForStringProto(cx, args);
+if (!rdata.str)
+return false;
+if (!rdata.g.init(cx, args))
+return false;
+/* Extract replacement string/function. */
+if (args.length() >= ReplaceOptArg && js_IsCallable(args[1])) {
+rdata.setReplacementFunction(&args[1].toObject());
+if (!LambdaIsGetElem(cx, *rdata.lambda, &rdata.elembase))
+return false;
+} else {
+JSLinearString *string = ArgToRootedString(cx, args, 1);
+if (!string)
+return false;
+rdata.setReplacementString(string);
+}
+rdata.fig.initFunction(ObjectOrNullValue(rdata.lambda));
+/*
+* Unlike its |String.prototype| brethren, |replace| doesn't convert
+* its input to a regular expression. (Even if it contains metachars.)
+*
+* However, if the user invokes our (non-standard) |flags| argument
+* extension then we revert to creating a regular expression. Note that
+* this is observable behavior through the side-effect mutation of the
+* |RegExp| statics.
+*/
+const FlatMatch *fm = rdata.g.tryFlatMatch(cx, rdata.str, ReplaceOptArg, args.length(), false);
+if (!fm) {
+if (cx->isExceptionPending())  /* oom in RopeMatch in tryFlatMatch */
+return false;
+return str_replace_regexp(cx, args, rdata);
+}
+if (fm->match() < 0) {
+args.rval().setString(rdata.str);
+return true;
+}
+if (rdata.lambda)
+return str_replace_flat_lambda(cx, args, rdata, *fm);
+return StrReplaceString(cx, rdata, *fm, args.rval());
+}
+namespace {
+class SplitMatchResult {
+size_t endIndex_;
+size_t length_;
+public:
+void setFailure() {
+JS_STATIC_ASSERT(SIZE_MAX > JSString::MAX_LENGTH);
+endIndex_ = SIZE_MAX;
+}
+bool isFailure() const {
+return endIndex_ == SIZE_MAX;
+}
+size_t endIndex() const {
+JS_ASSERT(!isFailure());
+return endIndex_;
+}
+size_t length() const {
+JS_ASSERT(!isFailure());
+return length_;
+}
+void setResult(size_t length, size_t endIndex) {
+length_ = length;
+endIndex_ = endIndex;
+}
+};
+} /* anonymous namespace */
+template<class Matcher>
+static ArrayObject *
+SplitHelper(JSContext *cx, Handle<JSLinearString*> str, uint32_t limit, const Matcher &splitMatch,
+Handle<TypeObject*> type)
+{
+size_t strLength = str->length();
+SplitMatchResult result;
+/* Step 11. */
+if (strLength == 0) {
+if (!splitMatch(cx, str, 0, &result))
+return nullptr;
+/*
+* NB: Unlike in the non-empty string case, it's perfectly fine
+*     (indeed the spec requires it) if we match at the end of the
+*     string.  Thus these cases should hold:
+*
+*   var a = "".split("");
+*   assertEq(a.length, 0);
+*   var b = "".split(/.?/);
+*   assertEq(b.length, 0);
+*/
+if (!result.isFailure())
+return NewDenseEmptyArray(cx);
+RootedValue v(cx, StringValue(str));
+return NewDenseCopiedArray(cx, 1, v.address());
+}
+/* Step 12. */
+size_t lastEndIndex = 0;
+size_t index = 0;
+/* Step 13. */
+AutoValueVector splits(cx);
+while (index < strLength) {
+/* Step 13(a). */
+if (!splitMatch(cx, str, index, &result))
+return nullptr;
+/*
+* Step 13(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 13(c)(ii) 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 (result.isFailure())
+break;
+/* Step 13(c)(i). */
+size_t sepLength = result.length();
+size_t endIndex = result.endIndex();
+if (sepLength == 0 && endIndex == strLength)
+break;
+/* Step 13(c)(ii). */
+if (endIndex == lastEndIndex) {
+index++;
+continue;
+}
+/* Step 13(c)(iii). */
+JS_ASSERT(lastEndIndex < endIndex);
+JS_ASSERT(sepLength <= strLength);
+JS_ASSERT(lastEndIndex + sepLength <= endIndex);
+/* Steps 13(c)(iii)(1-3). */
+size_t subLength = size_t(endIndex - sepLength - lastEndIndex);
+JSString *sub = js_NewDependentString(cx, str, lastEndIndex, subLength);
+if (!sub || !splits.append(StringValue(sub)))
+return nullptr;
+/* Step 13(c)(iii)(4). */
+if (splits.length() == limit)
+return NewDenseCopiedArray(cx, splits.length(), splits.begin());
+/* Step 13(c)(iii)(5). */
+lastEndIndex = endIndex;
+/* Step 13(c)(iii)(6-7). */
+if (Matcher::returnsCaptures) {
+RegExpStatics *res = cx->global()->getRegExpStatics();
+const MatchPairs &matches = res->getMatches();
+for (size_t i = 0; i < matches.parenCount(); i++) {
+/* Steps 13(c)(iii)(7)(a-c). */
+if (!matches[i + 1].isUndefined()) {
+JSSubString parsub;
+res->getParen(i + 1, &parsub);
+sub = js_NewStringCopyN<CanGC>(cx, parsub.chars, parsub.length);
+if (!sub || !splits.append(StringValue(sub)))
+return nullptr;
+} else {
+/* Only string entries have been accounted for so far. */
+AddTypePropertyId(cx, type, JSID_VOID, UndefinedValue());
+if (!splits.append(UndefinedValue()))
+return nullptr;
+}
+/* Step 13(c)(iii)(7)(d). */
+if (splits.length() == limit)
+return NewDenseCopiedArray(cx, splits.length(), splits.begin());
+}
+}
+/* Step 13(c)(iii)(8). */
+index = lastEndIndex;
+}
+/* Steps 14-15. */
+JSString *sub = js_NewDependentString(cx, str, lastEndIndex, strLength - lastEndIndex);
+if (!sub || !splits.append(StringValue(sub)))
+return nullptr;
+/* Step 16. */
+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);
+AutoValueVector splits(cx);
+if (!splits.reserve(resultlen))
+return nullptr;
+for (size_t i = 0; i < resultlen; ++i) {
+JSString *sub = staticStrings.getUnitStringForElement(cx, str, i);
+if (!sub)
+return nullptr;
+splits.infallibleAppend(StringValue(sub));
+}
+return NewDenseCopiedArray(cx, splits.length(), splits.begin());
+}
+namespace {
+/*
+* The SplitMatch operation from ES5 15.5.4.14 is implemented using different
+* paths for regular expression and string separators.
+*
+* The algorithm differs from the spec in that the we return the next index at
+* which a match happens.
+*/
+class SplitRegExpMatcher
+{
+RegExpShared &re;
+RegExpStatics *res;
+public:
+SplitRegExpMatcher(RegExpShared &re, RegExpStatics *res) : re(re), res(res) {}
+static const bool returnsCaptures = true;
+bool operator()(JSContext *cx, Handle<JSLinearString*> str, size_t index,
+SplitMatchResult *result) const
+{
+const jschar *chars = str->chars();
+size_t length = str->length();
+ScopedMatchPairs matches(&cx->tempLifoAlloc());
+RegExpRunStatus status = re.execute(cx, chars, length, &index, matches);
+if (status == RegExpRunStatus_Error)
+return false;
+if (status == RegExpRunStatus_Success_NotFound) {
+result->setFailure();
+return true;
+}
+if (!res->updateFromMatchPairs(cx, str, matches))
+return false;
+JSSubString sep;
+res->getLastMatch(&sep);
+result->setResult(sep.length, index);
+return true;
+}
+};
+class SplitStringMatcher
+{
+Rooted<JSLinearString*> sep;
+public:
+SplitStringMatcher(JSContext *cx, HandleLinearString sep)
+: sep(cx, sep)
+{}
+static const bool returnsCaptures = false;
+bool operator()(JSContext *cx, JSLinearString *str, size_t index, SplitMatchResult *res) const
+{
+JS_ASSERT(index == 0 || index < str->length());
+const jschar *chars = str->chars();
+int match = StringMatch(chars + index, str->length() - index,
+sep->chars(), sep->length());
+if (match == -1)
+res->setFailure();
+else
+res->setResult(sep->length(), index + match + sep->length());
+return true;
+}
+};
+} /* anonymous namespace */
+/* ES5 15.5.4.14 */
+bool
+js::str_split(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+/* Steps 1-2. */
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+RootedTypeObject type(cx, GetTypeCallerInitObject(cx, JSProto_Array));
+if (!type)
+return false;
+AddTypePropertyId(cx, type, JSID_VOID, Type::StringType());
+/* Step 5: Use the second argument as the split limit, if given. */
+uint32_t limit;
+if (args.hasDefined(1)) {
+double d;
+if (!ToNumber(cx, args[1], &d))
+return false;
+limit = ToUint32(d);
+} else {
+limit = UINT32_MAX;
+}
+/* Step 8. */
+RegExpGuard re(cx);
+RootedLinearString sepstr(cx);
+bool sepDefined = args.hasDefined(0);
+if (sepDefined) {
+if (IsObjectWithClass(args[0], ESClass_RegExp, cx)) {
+RootedObject obj(cx, &args[0].toObject());
+if (!RegExpToShared(cx, obj, &re))
+return false;
+} else {
+sepstr = ArgToRootedString(cx, args, 0);
+if (!sepstr)
+return false;
+}
+}
+/* Step 9. */
+if (limit == 0) {
+JSObject *aobj = NewDenseEmptyArray(cx);
+if (!aobj)
+return false;
+aobj->setType(type);
+args.rval().setObject(*aobj);
+return true;
+}
+/* Step 10. */
+if (!sepDefined) {
+RootedValue v(cx, StringValue(str));
+JSObject *aobj = NewDenseCopiedArray(cx, 1, v.address());
+if (!aobj)
+return false;
+aobj->setType(type);
+args.rval().setObject(*aobj);
+return true;
+}
+Rooted<JSLinearString*> linearStr(cx, str->ensureLinear(cx));
+if (!linearStr)
+return false;
+/* Steps 11-15. */
+RootedObject aobj(cx);
+if (!re.initialized()) {
+if (sepstr->length() == 0) {
+aobj = CharSplitHelper(cx, linearStr, limit);
+} else {
+SplitStringMatcher matcher(cx, sepstr);
+aobj = SplitHelper(cx, linearStr, limit, matcher, type);
+}
+} else {
+SplitRegExpMatcher matcher(*re, cx->global()->getRegExpStatics());
+aobj = SplitHelper(cx, linearStr, limit, matcher, type);
+}
+if (!aobj)
+return false;
+/* Step 16. */
+aobj->setType(type);
+args.rval().setObject(*aobj);
+return true;
+}
+JSObject *
+js::str_split_string(JSContext *cx, HandleTypeObject type, HandleString str, HandleString sep)
+{
+Rooted<JSLinearString*> linearStr(cx, str->ensureLinear(cx));
+if (!linearStr)
+return nullptr;
+Rooted<JSLinearString*> linearSep(cx, sep->ensureLinear(cx));
+if (!linearSep)
+return nullptr;
+uint32_t limit = UINT32_MAX;
+RootedObject aobj(cx);
+if (linearSep->length() == 0) {
+aobj = CharSplitHelper(cx, linearStr, limit);
+} else {
+SplitStringMatcher matcher(cx, linearSep);
+aobj = SplitHelper(cx, linearStr, limit, matcher, type);
+}
+if (!aobj)
+return nullptr;
+aobj->setType(type);
+return aobj;
+}
+static bool
+str_substr(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+int32_t length, len, begin;
+if (args.length() > 0) {
+length = int32_t(str->length());
+if (!ValueToIntegerRange(cx, args[0], &begin))
+return false;
+if (begin >= length) {
+args.rval().setString(cx->runtime()->emptyString);
+return true;
+}
+if (begin < 0) {
+begin += length; /* length + INT_MIN will always be less than 0 */
+if (begin < 0)
+begin = 0;
+}
+if (args.hasDefined(1)) {
+if (!ValueToIntegerRange(cx, args[1], &len))
+return false;
+if (len <= 0) {
+args.rval().setString(cx->runtime()->emptyString);
+return true;
+}
+if (uint32_t(length) < uint32_t(begin + len))
+len = length - begin;
+} else {
+len = length - begin;
+}
+str = DoSubstr(cx, str, size_t(begin), size_t(len));
+if (!str)
+return false;
+}
+args.rval().setString(str);
+return true;
+}
+/*
+* Python-esque sequence operations.
+*/
+static bool
+str_concat(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+JSString *str = ThisToStringForStringProto(cx, args);
+if (!str)
+return false;
+for (unsigned i = 0; i < args.length(); i++) {
+JSString *argStr = ToString<NoGC>(cx, args[i]);
+if (!argStr) {
+RootedString strRoot(cx, str);
+argStr = ToString<CanGC>(cx, args[i]);
+if (!argStr)
+return false;
+str = strRoot;
+}
+JSString *next = ConcatStrings<NoGC>(cx, str, argStr);
+if (next) {
+str = next;
+} else {
+RootedString strRoot(cx, str), argStrRoot(cx, argStr);
+str = ConcatStrings<CanGC>(cx, strRoot, argStrRoot);
+if (!str)
+return false;
+}
+}
+args.rval().setString(str);
+return true;
+}
+static bool
+str_slice(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+if (args.length() == 1 && args.thisv().isString() && args[0].isInt32()) {
+JSString *str = args.thisv().toString();
+size_t begin = args[0].toInt32();
+size_t end = str->length();
+if (begin <= end) {
+size_t length = end - begin;
+if (length == 0) {
+str = cx->runtime()->emptyString;
+} else {
+str = (length == 1)
+? cx->staticStrings().getUnitStringForElement(cx, str, begin)
+: js_NewDependentString(cx, str, begin, length);
+if (!str)
+return false;
+}
+args.rval().setString(str);
+return true;
+}
+}
+RootedString str(cx, ThisToStringForStringProto(cx, args));
+if (!str)
+return false;
+if (args.length() != 0) {
+double begin, end, length;
+if (!ToInteger(cx, args[0], &begin))
+return false;
+length = str->length();
+if (begin < 0) {
+begin += length;
+if (begin < 0)
+begin = 0;
+} else if (begin > length) {
+begin = length;
+}
+if (args.hasDefined(1)) {
+if (!ToInteger(cx, args[1], &end))
+return false;
+if (end < 0) {
+end += length;
+if (end < 0)
+end = 0;
+} else if (end > length) {
+end = length;
+}
+if (end < begin)
+end = begin;
+} else {
+end = length;
+}
+str = js_NewDependentString(cx, str,
+(size_t)begin,
+(size_t)(end - begin));
+if (!str)
+return false;
+}
+args.rval().setString(str);
+return true;
+}
+#if JS_HAS_STR_HTML_HELPERS
+/*
+* HTML composition aids.
+*/
+static bool
+tagify(JSContext *cx, const char *begin, HandleLinearString param, const char *end,
+CallReceiver call)
+{
+JSString *thisstr = ThisToStringForStringProto(cx, call);
+if (!thisstr)
+return false;
+JSLinearString *str = thisstr->ensureLinear(cx);
+if (!str)
+return false;
+if (!end)
+end = begin;
+size_t beglen = strlen(begin);
+size_t taglen = 1 + beglen + 1;                     /* '<begin' + '>' */
+if (param) {
+size_t numChars = param->length();
+const jschar *parchars = param->chars();
+for (size_t i = 0, parlen = numChars; i < parlen; ++i) {
+if (parchars[i] == '"')
+numChars += 5;                          /* len(&quot;) - len(") */
+}
+taglen += 2 + numChars + 1;                     /* '="param"' */
+}
+size_t endlen = strlen(end);
+taglen += str->length() + 2 + endlen + 1;           /* 'str</end>' */
+StringBuffer sb(cx);
+if (!sb.reserve(taglen))
+return false;
+sb.infallibleAppend('<');
+MOZ_ALWAYS_TRUE(sb.appendInflated(begin, beglen));
+if (param) {
+sb.infallibleAppend('=');
+sb.infallibleAppend('"');
+const jschar *parchars = param->chars();
+for (size_t i = 0, parlen = param->length(); i < parlen; ++i) {
+if (parchars[i] != '"') {
+sb.infallibleAppend(parchars[i]);
+} else {
+MOZ_ALWAYS_TRUE(sb.append("&quot;"));
+}
+}
+sb.infallibleAppend('"');
+}
+sb.infallibleAppend('>');
+MOZ_ALWAYS_TRUE(sb.append(str));
+sb.infallibleAppend('<');
+sb.infallibleAppend('/');
+MOZ_ALWAYS_TRUE(sb.appendInflated(end, endlen));
+sb.infallibleAppend('>');
+JSFlatString *retstr = sb.finishString();
+if (!retstr)
+return false;
+call.rval().setString(retstr);
+return true;
+}
+static bool
+tagify_value(JSContext *cx, CallArgs args, const char *begin, const char *end)
+{
+RootedLinearString param(cx, ArgToRootedString(cx, args, 0));
+if (!param)
+return false;
+return tagify(cx, begin, param, end, args);
+}
+static bool
+str_bold(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "b", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_italics(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "i", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_fixed(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "tt", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_fontsize(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify_value(cx, CallArgsFromVp(argc, vp), "font size", "font");
+}
+static bool
+str_fontcolor(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify_value(cx, CallArgsFromVp(argc, vp), "font color", "font");
+}
+static bool
+str_link(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify_value(cx, CallArgsFromVp(argc, vp), "a href", "a");
+}
+static bool
+str_anchor(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify_value(cx, CallArgsFromVp(argc, vp), "a name", "a");
+}
+static bool
+str_strike(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "strike", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_small(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "small", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_big(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "big", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_blink(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "blink", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_sup(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "sup", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+static bool
+str_sub(JSContext *cx, unsigned argc, Value *vp)
+{
+return tagify(cx, "sub", NullPtr(), nullptr, CallReceiverFromVp(vp));
+}
+#endif /* JS_HAS_STR_HTML_HELPERS */
+static const JSFunctionSpec string_methods[] = {
+#if JS_HAS_TOSOURCE
+JS_FN("quote",             str_quote,             0,JSFUN_GENERIC_NATIVE),
+JS_FN(js_toSource_str,     str_toSource,          0,0),
+#endif
+/* Java-like methods. */
+JS_FN(js_toString_str,     js_str_toString,       0,0),
+JS_FN(js_valueOf_str,      js_str_toString,       0,0),
+JS_FN("substring",         str_substring,         2,JSFUN_GENERIC_NATIVE),
+JS_FN("toLowerCase",       str_toLowerCase,       0,JSFUN_GENERIC_NATIVE),
+JS_FN("toUpperCase",       str_toUpperCase,       0,JSFUN_GENERIC_NATIVE),
+JS_FN("charAt",            js_str_charAt,         1,JSFUN_GENERIC_NATIVE),
+JS_FN("charCodeAt",        js_str_charCodeAt,     1,JSFUN_GENERIC_NATIVE),
+JS_SELF_HOSTED_FN("codePointAt", "String_codePointAt", 1,0),
+JS_FN("contains",          str_contains,          1,JSFUN_GENERIC_NATIVE),
+JS_FN("indexOf",           str_indexOf,           1,JSFUN_GENERIC_NATIVE),
+JS_FN("lastIndexOf",       str_lastIndexOf,       1,JSFUN_GENERIC_NATIVE),
+JS_FN("startsWith",        str_startsWith,        1,JSFUN_GENERIC_NATIVE),
+JS_FN("endsWith",          str_endsWith,          1,JSFUN_GENERIC_NATIVE),
+JS_FN("trim",              str_trim,              0,JSFUN_GENERIC_NATIVE),
+JS_FN("trimLeft",          str_trimLeft,          0,JSFUN_GENERIC_NATIVE),
+JS_FN("trimRight",         str_trimRight,         0,JSFUN_GENERIC_NATIVE),
+JS_FN("toLocaleLowerCase", str_toLocaleLowerCase, 0,JSFUN_GENERIC_NATIVE),
+JS_FN("toLocaleUpperCase", str_toLocaleUpperCase, 0,JSFUN_GENERIC_NATIVE),
+#if EXPOSE_INTL_API
+JS_SELF_HOSTED_FN("localeCompare", "String_localeCompare", 1,0),
+#else
+JS_FN("localeCompare",     str_localeCompare,     1,JSFUN_GENERIC_NATIVE),
+#endif
+JS_SELF_HOSTED_FN("repeat", "String_repeat",      1,0),
+#if EXPOSE_INTL_API
+JS_FN("normalize",         str_normalize,         0,JSFUN_GENERIC_NATIVE),
+#endif
+/* Perl-ish methods (search is actually Python-esque). */
+JS_FN("match",             str_match,             1,JSFUN_GENERIC_NATIVE),
+JS_FN("search",            str_search,            1,JSFUN_GENERIC_NATIVE),
+JS_FN("replace",           str_replace,           2,JSFUN_GENERIC_NATIVE),
+JS_FN("split",             str_split,             2,JSFUN_GENERIC_NATIVE),
+JS_FN("substr",            str_substr,            2,JSFUN_GENERIC_NATIVE),
+/* Python-esque sequence methods. */
+JS_FN("concat",            str_concat,            1,JSFUN_GENERIC_NATIVE),
+JS_FN("slice",             str_slice,             2,JSFUN_GENERIC_NATIVE),
+/* HTML string methods. */
+#if JS_HAS_STR_HTML_HELPERS
+JS_FN("bold",              str_bold,              0,0),
+JS_FN("italics",           str_italics,           0,0),
+JS_FN("fixed",             str_fixed,             0,0),
+JS_FN("fontsize",          str_fontsize,          1,0),
+JS_FN("fontcolor",         str_fontcolor,         1,0),
+JS_FN("link",              str_link,              1,0),
+JS_FN("anchor",            str_anchor,            1,0),
+JS_FN("strike",            str_strike,            0,0),
+JS_FN("small",             str_small,             0,0),
+JS_FN("big",               str_big,               0,0),
+JS_FN("blink",             str_blink,             0,0),
+JS_FN("sup",               str_sup,               0,0),
+JS_FN("sub",               str_sub,               0,0),
+#endif
+JS_SELF_HOSTED_FN("@@iterator", "String_iterator", 0,0),
+JS_FS_END
+};
+bool
+js_String(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+RootedString str(cx);
+if (args.length() > 0) {
+str = ToString<CanGC>(cx, args[0]);
+if (!str)
+return false;
+} else {
+str = cx->runtime()->emptyString;
+}
+if (args.isConstructing()) {
+StringObject *strobj = StringObject::create(cx, str);
+if (!strobj)
+return false;
+args.rval().setObject(*strobj);
+return true;
+}
+args.rval().setString(str);
+return true;
+}
+bool
+js::str_fromCharCode(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+JS_ASSERT(args.length() <= ARGS_LENGTH_MAX);
+if (args.length() == 1) {
+uint16_t code;
+if (!ToUint16(cx, args[0], &code))
+return false;
+if (StaticStrings::hasUnit(code)) {
+args.rval().setString(cx->staticStrings().getUnit(code));
+return true;
+}
+args[0].setInt32(code);
+}
+jschar *chars = cx->pod_malloc<jschar>(args.length() + 1);
+if (!chars)
+return false;
+for (unsigned i = 0; i < args.length(); i++) {
+uint16_t code;
+if (!ToUint16(cx, args[i], &code)) {
+js_free(chars);
+return false;
+}
+chars[i] = (jschar)code;
+}
+chars[args.length()] = 0;
+JSString *str = js_NewString<CanGC>(cx, chars, args.length());
+if (!str) {
+js_free(chars);
+return false;
+}
+args.rval().setString(str);
+return true;
+}
+static const JSFunctionSpec string_static_methods[] = {
+JS_FN("fromCharCode", js::str_fromCharCode, 1, 0),
+JS_SELF_HOSTED_FN("fromCodePoint", "String_static_fromCodePoint", 0,0),
+// This must be at the end because of bug 853075: functions listed after
+// self-hosted methods aren't available in self-hosted code.
+#if EXPOSE_INTL_API
+JS_SELF_HOSTED_FN("localeCompare", "String_static_localeCompare", 2,0),
+#endif
+JS_FS_END
+};
+/* static */ Shape *
+StringObject::assignInitialShape(ExclusiveContext *cx, Handle<StringObject*> obj)
+{
+JS_ASSERT(obj->nativeEmpty());
+return obj->addDataProperty(cx, cx->names().length, LENGTH_SLOT,
+JSPROP_PERMANENT | JSPROP_READONLY);
+}
+JSObject *
+js_InitStringClass(JSContext *cx, HandleObject obj)
+{
+JS_ASSERT(obj->isNative());
+Rooted<GlobalObject*> global(cx, &obj->as<GlobalObject>());
+Rooted<JSString*> empty(cx, cx->runtime()->emptyString);
+RootedObject proto(cx, global->createBlankPrototype(cx, &StringObject::class_));
+if (!proto || !proto->as<StringObject>().init(cx, empty))
+return nullptr;
+/* Now create the String function. */
+RootedFunction ctor(cx);
+ctor = global->createConstructor(cx, js_String, cx->names().String, 1);
+if (!ctor)
+return nullptr;
+if (!LinkConstructorAndPrototype(cx, ctor, proto))
+return nullptr;
+if (!DefinePropertiesAndBrand(cx, proto, nullptr, string_methods) ||
+!DefinePropertiesAndBrand(cx, ctor, nullptr, string_static_methods))
+{
+return nullptr;
+}
+if (!GlobalObject::initBuiltinConstructor(cx, global, JSProto_String, ctor, proto))
+return nullptr;
+/*
+* Define escape/unescape, the URI encode/decode functions, and maybe
+* uneval on the global object.
+*/
+if (!JS_DefineFunctions(cx, global, string_functions))
+return nullptr;
+return proto;
+}
+template <AllowGC allowGC>
+JSFlatString *
+js_NewString(ThreadSafeContext *cx, jschar *chars, size_t length)
+{
+if (length == 1) {
+jschar c = chars[0];
+if (StaticStrings::hasUnit(c)) {
+// Free |chars| because we're taking possession of it, but it's no
+// longer needed because we use the static string instead.
+js_free(chars);
+return cx->staticStrings().getUnit(c);
+}
+}
+return JSFlatString::new_<allowGC>(cx, chars, length);
+}
+template JSFlatString *
+js_NewString<CanGC>(ThreadSafeContext *cx, jschar *chars, size_t length);
+template JSFlatString *
+js_NewString<NoGC>(ThreadSafeContext *cx, jschar *chars, size_t length);
+JSLinearString *
+js_NewDependentString(JSContext *cx, JSString *baseArg, size_t start, size_t length)
+{
+if (length == 0)
+return cx->emptyString();
+JSLinearString *base = baseArg->ensureLinear(cx);
+if (!base)
+return nullptr;
+if (start == 0 && length == base->length())
+return base;
+const jschar *chars = base->chars() + start;
+if (JSLinearString *staticStr = cx->staticStrings().lookup(chars, length))
+return staticStr;
+return JSDependentString::new_(cx, base, chars, length);
+}
+template <AllowGC allowGC>
+JSFlatString *
+js_NewStringCopyN(ExclusiveContext *cx, const jschar *s, size_t n)
+{
+if (JSFatInlineString::lengthFits(n))
+return NewFatInlineString<allowGC>(cx, TwoByteChars(s, n));
+jschar *news = cx->pod_malloc<jschar>(n + 1);
+if (!news)
+return nullptr;
+js_strncpy(news, s, n);
+news[n] = 0;
+JSFlatString *str = js_NewString<allowGC>(cx, news, n);
+if (!str)
+js_free(news);
+return str;
+}
+template JSFlatString *
+js_NewStringCopyN<CanGC>(ExclusiveContext *cx, const jschar *s, size_t n);
+template JSFlatString *
+js_NewStringCopyN<NoGC>(ExclusiveContext *cx, const jschar *s, size_t n);
+template <AllowGC allowGC>
+JSFlatString *
+js_NewStringCopyN(ThreadSafeContext *cx, const char *s, size_t n)
+{
+if (JSFatInlineString::lengthFits(n))
+return NewFatInlineString<allowGC>(cx, JS::Latin1Chars(s, n));
+jschar *chars = InflateString(cx, s, &n);
+if (!chars)
+return nullptr;
+JSFlatString *str = js_NewString<allowGC>(cx, chars, n);
+if (!str)
+js_free(chars);
+return str;
+}
+template JSFlatString *
+js_NewStringCopyN<CanGC>(ThreadSafeContext *cx, const char *s, size_t n);
+template JSFlatString *
+js_NewStringCopyN<NoGC>(ThreadSafeContext *cx, const char *s, size_t n);
+template <AllowGC allowGC>
+JSFlatString *
+js_NewStringCopyZ(ExclusiveContext *cx, const jschar *s)
+{
+size_t n = js_strlen(s);
+if (JSFatInlineString::lengthFits(n))
+return NewFatInlineString<allowGC>(cx, TwoByteChars(s, n));
+size_t m = (n + 1) * sizeof(jschar);
+jschar *news = (jschar *) cx->malloc_(m);
+if (!news)
+return nullptr;
+js_memcpy(news, s, m);
+JSFlatString *str = js_NewString<allowGC>(cx, news, n);
+if (!str)
+js_free(news);
+return str;
+}
+template JSFlatString *
+js_NewStringCopyZ<CanGC>(ExclusiveContext *cx, const jschar *s);
+template JSFlatString *
+js_NewStringCopyZ<NoGC>(ExclusiveContext *cx, const jschar *s);
+template <AllowGC allowGC>
+JSFlatString *
+js_NewStringCopyZ(ThreadSafeContext *cx, const char *s)
+{
+return js_NewStringCopyN<allowGC>(cx, s, strlen(s));
+}
+template JSFlatString *
+js_NewStringCopyZ<CanGC>(ThreadSafeContext *cx, const char *s);
+template JSFlatString *
+js_NewStringCopyZ<NoGC>(ThreadSafeContext *cx, const char *s);
+const char *
+js_ValueToPrintable(JSContext *cx, const Value &vArg, JSAutoByteString *bytes, bool asSource)
+{
+RootedValue v(cx, vArg);
+JSString *str;
+if (asSource)
+str = ValueToSource(cx, v);
+else
+str = ToString<CanGC>(cx, v);
+if (!str)
+return nullptr;
+str = js_QuoteString(cx, str, 0);
+if (!str)
+return nullptr;
+return bytes->encodeLatin1(cx, str);
+}
+template <AllowGC allowGC>
+JSString *
+js::ToStringSlow(ExclusiveContext *cx, typename MaybeRooted<Value, allowGC>::HandleType arg)
+{
+/* As with ToObjectSlow, callers must verify that |arg| isn't a string. */
+JS_ASSERT(!arg.isString());
+Value v = arg;
+if (!v.isPrimitive()) {
+if (!cx->shouldBeJSContext() || !allowGC)
+return nullptr;
+RootedValue v2(cx, v);
+if (!ToPrimitive(cx->asJSContext(), JSTYPE_STRING, &v2))
+return nullptr;
+v = v2;
+}
+JSString *str;
+if (v.isString()) {
+str = v.toString();
+} else if (v.isInt32()) {
+str = Int32ToString<allowGC>(cx, v.toInt32());
+} else if (v.isDouble()) {
+str = NumberToString<allowGC>(cx, v.toDouble());
+} else if (v.isBoolean()) {
+str = js_BooleanToString(cx, v.toBoolean());
+} else if (v.isNull()) {
+str = cx->names().null;
+} else {
+str = cx->names().undefined;
+}
+return str;
+}
+template JSString *
+js::ToStringSlow<CanGC>(ExclusiveContext *cx, HandleValue arg);
+template JSString *
+js::ToStringSlow<NoGC>(ExclusiveContext *cx, Value arg);
+JS_PUBLIC_API(JSString *)
+js::ToStringSlow(JSContext *cx, HandleValue v)
+{
+return ToStringSlow<CanGC>(cx, v);
+}
+JSString *
+js::ValueToSource(JSContext *cx, HandleValue v)
+{
+JS_CHECK_RECURSION(cx, return nullptr);
+assertSameCompartment(cx, v);
+if (v.isUndefined())
+return cx->names().void0;
+if (v.isString())
+return StringToSource(cx, v.toString());
+if (v.isPrimitive()) {
+/* Special case to preserve negative zero, _contra_ toString. */
+if (v.isDouble() && IsNegativeZero(v.toDouble())) {
+/* NB: _ucNstr rather than _ucstr to indicate non-terminated. */
+static const jschar js_negzero_ucNstr[] = {'-', '0'};
+return js_NewStringCopyN<CanGC>(cx, js_negzero_ucNstr, 2);
+}
+return ToString<CanGC>(cx, v);
+}
+RootedValue fval(cx);
+RootedObject obj(cx, &v.toObject());
+if (!JSObject::getProperty(cx, obj, obj, cx->names().toSource, &fval))
+return nullptr;
+if (js_IsCallable(fval)) {
+RootedValue rval(cx);
+if (!Invoke(cx, ObjectValue(*obj), fval, 0, nullptr, &rval))
+return nullptr;
+return ToString<CanGC>(cx, rval);
+}
+return ObjectToSource(cx, obj);
+}
+JSString *
+js::StringToSource(JSContext *cx, JSString *str)
+{
+return js_QuoteString(cx, str, '"');
+}
+bool
+js::EqualStrings(JSContext *cx, JSString *str1, JSString *str2, bool *result)
+{
+if (str1 == str2) {
+*result = true;
+return true;
+}
+size_t length1 = str1->length();
+if (length1 != str2->length()) {
+*result = false;
+return true;
+}
+JSLinearString *linear1 = str1->ensureLinear(cx);
+if (!linear1)
+return false;
+JSLinearString *linear2 = str2->ensureLinear(cx);
+if (!linear2)
+return false;
+*result = PodEqual(linear1->chars(), linear2->chars(), length1);
+return true;
+}
+bool
+js::EqualStrings(JSLinearString *str1, JSLinearString *str2)
+{
+if (str1 == str2)
+return true;
+size_t length1 = str1->length();
+if (length1 != str2->length())
+return false;
+return PodEqual(str1->chars(), str2->chars(), length1);
+}
+static bool
+CompareStringsImpl(JSContext *cx, JSString *str1, JSString *str2, int32_t *result)
+{
+JS_ASSERT(str1);
+JS_ASSERT(str2);
+if (str1 == str2) {
+*result = 0;
+return true;
+}
+const jschar *s1 = str1->getChars(cx);
+if (!s1)
+return false;
+const jschar *s2 = str2->getChars(cx);
+if (!s2)
+return false;
+*result = CompareChars(s1, str1->length(), s2, str2->length());
+return true;
+}
+bool
+js::CompareStrings(JSContext *cx, JSString *str1, JSString *str2, int32_t *result)
+{
+return CompareStringsImpl(cx, str1, str2, result);
+}
+int32_t
+js::CompareAtoms(JSAtom *atom1, JSAtom *atom2)
+{
+return CompareChars(atom1->chars(), atom1->length(), atom2->chars(), atom2->length());
+}
+bool
+js::StringEqualsAscii(JSLinearString *str, const char *asciiBytes)
+{
+size_t length = strlen(asciiBytes);
+#ifdef DEBUG
+for (size_t i = 0; i != length; ++i)
+JS_ASSERT(unsigned(asciiBytes[i]) <= 127);
+#endif
+if (length != str->length())
+return false;
+const jschar *chars = str->chars();
+for (size_t i = 0; i != length; ++i) {
+if (unsigned(asciiBytes[i]) != unsigned(chars[i]))
+return false;
+}
+return true;
+}
+size_t
+js_strlen(const jschar *s)
+{
+const jschar *t;
+for (t = s; *t != 0; t++)
+continue;
+return (size_t)(t - s);
+}
+int32_t
+js_strcmp(const jschar *lhs, const jschar *rhs)
+{
+while (true) {
+if (*lhs != *rhs)
+return int32_t(*lhs) - int32_t(*rhs);
+if (*lhs == 0)
+return 0;
+++lhs, ++rhs;
+}
+}
+jschar *
+js_strdup(js::ThreadSafeContext *cx, const jschar *s)
+{
+size_t n = js_strlen(s);
+jschar *ret = cx->pod_malloc<jschar>(n + 1);
+if (!ret)
+return nullptr;
+js_strncpy(ret, s, n);
+ret[n] = '\0';
+return ret;
+}
+jschar *
+js_strchr_limit(const jschar *s, jschar c, const jschar *limit)
+{
+while (s < limit) {
+if (*s == c)
+return (jschar *)s;
+s++;
+}
+return nullptr;
+}
+jschar *
+js::InflateString(ThreadSafeContext *cx, const char *bytes, size_t *lengthp)
+{
+size_t nchars;
+jschar *chars;
+size_t nbytes = *lengthp;
+nchars = nbytes;
+chars = cx->pod_malloc<jschar>(nchars + 1);
+if (!chars)
+goto bad;
+for (size_t i = 0; i < nchars; i++)
+chars[i] = (unsigned char) bytes[i];
+*lengthp = nchars;
+chars[nchars] = 0;
+return chars;
+bad:
+// For compatibility with callers of JS_DecodeBytes we must zero lengthp
+// on errors.
+*lengthp = 0;
+return nullptr;
+}
+bool
+js::DeflateStringToBuffer(JSContext *maybecx, const jschar *src, size_t srclen,
+char *dst, size_t *dstlenp)
+{
+size_t dstlen = *dstlenp;
+if (srclen > dstlen) {
+for (size_t i = 0; i < dstlen; i++)
+dst[i] = (char) src[i];
+if (maybecx) {
+AutoSuppressGC suppress(maybecx);
+JS_ReportErrorNumber(maybecx, js_GetErrorMessage, nullptr,
+JSMSG_BUFFER_TOO_SMALL);
+}
+return false;
+}
+for (size_t i = 0; i < srclen; i++)
+dst[i] = (char) src[i];
+*dstlenp = srclen;
+return true;
+}
+#define ____ false
+/*
+* Identifier start chars:
+* -      36:    $
+* -  65..90: A..Z
+* -      95:    _
+* - 97..122: a..z
+*/
+const bool js_isidstart[] = {
+/*       0     1     2     3     4     5     6     7     8     9  */
+/*  0 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  1 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  2 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  3 */ ____, ____, ____, ____, ____, ____, true, ____, ____, ____,
+/*  4 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  5 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  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, ____, ____, ____, ____, ____
+};
+/*
+* Identifier chars:
+* -      36:    $
+* -  48..57: 0..9
+* -  65..90: A..Z
+* -      95:    _
+* - 97..122: a..z
+*/
+const bool js_isident[] = {
+/*       0     1     2     3     4     5     6     7     8     9  */
+/*  0 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  1 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  2 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  3 */ ____, ____, ____, ____, ____, ____, true, ____, ____, ____,
+/*  4 */ ____, ____, ____, ____, ____, ____, ____, ____, 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, ____, ____, ____, ____, ____
+};
+/* Whitespace chars: '\t', '\n', '\v', '\f', '\r', ' '. */
+const bool js_isspace[] = {
+/*       0     1     2     3     4     5     6     7     8     9  */
+/*  0 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, true,
+/*  1 */ true, true, true, true, ____, ____, ____, ____, ____, ____,
+/*  2 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  3 */ ____, ____, true, ____, ____, ____, ____, ____, ____, ____,
+/*  4 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  5 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  6 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  7 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  8 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/*  9 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/* 10 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/* 11 */ ____, ____, ____, ____, ____, ____, ____, ____, ____, ____,
+/* 12 */ ____, ____, ____, ____, ____, ____, ____, ____
+};
+/*
+* Uri reserved chars + #:
+* - 35: #
+* - 36: $
+* - 38: &
+* - 43: +
+* - 44: ,
+* - 47: /
+* - 58: :
+* - 59: ;
+* - 61: =
+* - 63: ?
+* - 64: @
+*/
+static const bool js_isUriReservedPlusPound[] = {
+/*       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 */ ____, ____, ____, ____, ____, ____, ____, ____
+};
+/*
+* 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[] = {
+/*       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, ____
+};
+#undef ____
+#define URI_CHUNK 64U
+static inline bool
+TransferBufferToString(StringBuffer &sb, MutableHandleValue rval)
+{
+JSString *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'.
+*/
+static bool
+Encode(JSContext *cx, Handle<JSLinearString*> str, const bool *unescapedSet,
+const bool *unescapedSet2, MutableHandleValue rval)
+{
+static const char HexDigits[] = "0123456789ABCDEF"; /* NB: uppercase */
+size_t length = str->length();
+if (length == 0) {
+rval.setString(cx->runtime()->emptyString);
+return true;
+}
+const jschar *chars = str->chars();
+StringBuffer sb(cx);
+if (!sb.reserve(length))
+return false;
+jschar hexBuf[4];
+hexBuf[0] = '%';
+hexBuf[3] = 0;
+for (size_t k = 0; k < length; k++) {
+jschar c = chars[k];
+if (c < 128 && (unescapedSet[c] || (unescapedSet2 && unescapedSet2[c]))) {
+if (!sb.append(c))
+return false;
+} else {
+if ((c >= 0xDC00) && (c <= 0xDFFF)) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_BAD_URI, nullptr);
+return false;
+}
+uint32_t v;
+if (c < 0xD800 || c > 0xDBFF) {
+v = c;
+} else {
+k++;
+if (k == length) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr,
+JSMSG_BAD_URI, nullptr);
+return false;
+}
+jschar c2 = chars[k];
+if ((c2 < 0xDC00) || (c2 > 0xDFFF)) {
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr,
+JSMSG_BAD_URI, nullptr);
+return false;
+}
+v = ((c - 0xD800) << 10) + (c2 - 0xDC00) + 0x10000;
+}
+uint8_t utf8buf[4];
+size_t L = js_OneUcs4ToUtf8Char(utf8buf, v);
+for (size_t j = 0; j < L; j++) {
+hexBuf[1] = HexDigits[utf8buf[j] >> 4];
+hexBuf[2] = HexDigits[utf8buf[j] & 0xf];
+if (!sb.append(hexBuf, 3))
+return false;
+}
+}
+}
+return TransferBufferToString(sb, rval);
+}
+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;
+}
+const jschar *chars = str->chars();
+StringBuffer sb(cx);
+for (size_t k = 0; k < length; k++) {
+jschar c = chars[k];
+if (c == '%') {
+size_t start = k;
+if ((k + 2) >= length)
+goto report_bad_uri;
+if (!JS7_ISHEX(chars[k+1]) || !JS7_ISHEX(chars[k+2]))
+goto report_bad_uri;
+uint32_t B = JS7_UNHEX(chars[k+1]) * 16 + JS7_UNHEX(chars[k+2]);
+k += 2;
+if (!(B & 0x80)) {
+c = (jschar)B;
+} else {
+int n = 1;
+while (B & (0x80 >> n))
+n++;
+if (n == 1 || n > 4)
+goto report_bad_uri;
+uint8_t octets[4];
+octets[0] = (uint8_t)B;
+if (k + 3 * (n - 1) >= length)
+goto report_bad_uri;
+for (int j = 1; j < n; j++) {
+k++;
+if (chars[k] != '%')
+goto report_bad_uri;
+if (!JS7_ISHEX(chars[k+1]) || !JS7_ISHEX(chars[k+2]))
+goto report_bad_uri;
+B = JS7_UNHEX(chars[k+1]) * 16 + JS7_UNHEX(chars[k+2]);
+if ((B & 0xC0) != 0x80)
+goto report_bad_uri;
+k += 2;
+octets[j] = (char)B;
+}
+uint32_t v = JS::Utf8ToOneUcs4Char(octets, n);
+if (v >= 0x10000) {
+v -= 0x10000;
+if (v > 0xFFFFF)
+goto report_bad_uri;
+c = (jschar)((v & 0x3FF) + 0xDC00);
+jschar H = (jschar)((v >> 10) + 0xD800);
+if (!sb.append(H))
+return false;
+} else {
+c = (jschar)v;
+}
+}
+if (c < 128 && reservedSet && reservedSet[c]) {
+if (!sb.append(chars + start, k - start + 1))
+return false;
+} else {
+if (!sb.append(c))
+return false;
+}
+} else {
+if (!sb.append(c))
+return false;
+}
+}
+return TransferBufferToString(sb, rval);
+report_bad_uri:
+JS_ReportErrorNumber(cx, js_GetErrorMessage, nullptr, JSMSG_BAD_URI);
+/* FALL THROUGH */
+return false;
+}
+static bool
+str_decodeURI(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+Rooted<JSLinearString*> str(cx, ArgToRootedString(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)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+Rooted<JSLinearString*> str(cx, ArgToRootedString(cx, args, 0));
+if (!str)
+return false;
+return Decode(cx, str, nullptr, args.rval());
+}
+static bool
+str_encodeURI(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+Rooted<JSLinearString*> str(cx, ArgToRootedString(cx, args, 0));
+if (!str)
+return false;
+return Encode(cx, str, js_isUriUnescaped, js_isUriReservedPlusPound, args.rval());
+}
+static bool
+str_encodeURI_Component(JSContext *cx, unsigned argc, Value *vp)
+{
+CallArgs args = CallArgsFromVp(argc, vp);
+Rooted<JSLinearString*> str(cx, ArgToRootedString(cx, args, 0));
+if (!str)
+return false;
+return Encode(cx, str, js_isUriUnescaped, nullptr, args.rval());
+}
+/*
+* Convert one UCS-4 char and write it into a UTF-8 buffer, which must be at
+* least 4 bytes long.  Return the number of UTF-8 bytes of data written.
+*/
+int
+js_OneUcs4ToUtf8Char(uint8_t *utf8Buffer, uint32_t ucs4Char)
+{
+int utf8Length = 1;
+JS_ASSERT(ucs4Char <= 0x10FFFF);
+if (ucs4Char < 0x80) {
+*utf8Buffer = (uint8_t)ucs4Char;
+} else {
+int i;
+uint32_t a = ucs4Char >> 11;
+utf8Length = 2;
+while (a) {
+a >>= 5;
+utf8Length++;
+}
+i = utf8Length;
+while (--i) {
+utf8Buffer[i] = (uint8_t)((ucs4Char & 0x3F) | 0x80);
+ucs4Char >>= 6;
+}
+*utf8Buffer = (uint8_t)(0x100 - (1 << (8-utf8Length)) + ucs4Char);
+}
+return utf8Length;
+}
+size_t
+js::PutEscapedStringImpl(char *buffer, size_t bufferSize, FILE *fp, JSLinearString *str,
+uint32_t quote)
+{
+return PutEscapedStringImpl(buffer, bufferSize, fp, str->chars(),
+str->length(), quote);
+}
+size_t
+js::PutEscapedStringImpl(char *buffer, size_t bufferSize, FILE *fp, const jschar *chars,
+size_t length, uint32_t quote)
+{
+enum {
+STOP, FIRST_QUOTE, LAST_QUOTE, CHARS, ESCAPE_START, ESCAPE_MORE
+} state;
+JS_ASSERT(quote == 0 || quote == '\'' || quote == '"');
+JS_ASSERT_IF(!buffer, bufferSize == 0);
+JS_ASSERT_IF(fp, !buffer);
+if (bufferSize == 0)
+buffer = nullptr;
+else
+bufferSize--;
+const jschar *charsEnd = chars + length;
+size_t n = 0;
+state = FIRST_QUOTE;
+unsigned shift = 0;
+unsigned hex = 0;
+unsigned u = 0;
+char c = 0;  /* to quell GCC warnings */
+for (;;) {
+switch (state) {
+case STOP:
+goto stop;
+case FIRST_QUOTE:
+state = CHARS;
+goto do_quote;
+case LAST_QUOTE:
+state = STOP;
+do_quote:
+if (quote == 0)
+continue;
+c = (char)quote;
+break;
+case CHARS:
+if (chars == charsEnd) {
+state = LAST_QUOTE;
+continue;
+}
+u = *chars++;
+if (u < ' ') {
+if (u != 0) {
+const char *escape = strchr(js_EscapeMap, (int)u);
+if (escape) {
+u = escape[1];
+goto do_escape;
+}
+}
+goto do_hex_escape;
+}
+if (u < 127) {
+if (u == quote || u == '\\')
+goto do_escape;
+c = (char)u;
+} else if (u < 0x100) {
+goto do_hex_escape;
+} else {
+shift = 16;
+hex = u;
+u = 'u';
+goto do_escape;
+}
+break;
+do_hex_escape:
+shift = 8;
+hex = u;
+u = 'x';
+do_escape:
+c = '\\';
+state = ESCAPE_START;
+break;
+case ESCAPE_START:
+JS_ASSERT(' ' <= u && u < 127);
+c = (char)u;
+state = ESCAPE_MORE;
+break;
+case ESCAPE_MORE:
+if (shift == 0) {
+state = CHARS;
+continue;
+}
+shift -= 4;
+u = 0xF & (hex >> shift);
+c = (char)(u + (u < 10 ? '0' : 'A' - 10));
+break;
+}
+if (buffer) {
+JS_ASSERT(n <= bufferSize);
+if (n != bufferSize) {
+buffer[n] = c;
+} else {
+buffer[n] = '\0';
+buffer = nullptr;
+}
+} else if (fp) {
+if (fputc(c, fp) < 0)
+return size_t(-1);
+}
+n++;
+}
+stop:
+if (buffer)
+buffer[n] = '\0';
+return n;
+}

The Tor Browser / file comparison

comparison: js/src/jsstr.cpp

js/src/jsstr.cpp