The Tor Browser: js/src/jsapi.h@a63d609f5ebe (annotated)

js/src/jsapi.h@a63d609f5ebe (annotated)

js/src/jsapi.h

Thu, 15 Jan 2015 15:55:04 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:55:04 +0100
branch: TOR_BUG_9701
changeset 9: a63d609f5ebe
permissions: -rw-r--r--

Back out 97036ab72558 which inappropriately compared turds to third parties.

 /* -*- 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/. */
 /* JavaScript API. */
 #ifndef jsapi_h
 #define jsapi_h
 #include "mozilla/FloatingPoint.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/RangedPtr.h"
 #include <stdarg.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
 #include "jsalloc.h"
 #include "jspubtd.h"
 #include "js/CallArgs.h"
 #include "js/Class.h"
 #include "js/HashTable.h"
 #include "js/Id.h"
 #include "js/Principals.h"
 #include "js/RootingAPI.h"
 #include "js/TracingAPI.h"
 #include "js/Utility.h"
 #include "js/Value.h"
 #include "js/Vector.h"
 /************************************************************************/
 namespace JS {
 class Latin1CharsZ;
 class TwoByteChars;
 #if defined JS_THREADSAFE && defined JS_DEBUG
 class JS_PUBLIC_API(AutoCheckRequestDepth)
 {
     JSContext *cx;
   public:
     AutoCheckRequestDepth(JSContext *cx);
     AutoCheckRequestDepth(js::ContextFriendFields *cx);
     ~AutoCheckRequestDepth();
 };
 # define CHECK_REQUEST(cx) \
     JS::AutoCheckRequestDepth _autoCheckRequestDepth(cx)
 #else
 # define CHECK_REQUEST(cx) \
     ((void) 0)
 #endif /* JS_THREADSAFE && JS_DEBUG */
 #ifdef JS_DEBUG
 /*
  * Assert that we're not doing GC on cx, that we're in a request as
  * needed, and that the compartments for cx and v are correct.
  * Also check that GC would be safe at this point.
  */
 JS_PUBLIC_API(void)
 AssertArgumentsAreSane(JSContext *cx, JS::HandleValue v);
 #else
 inline void AssertArgumentsAreSane(JSContext *cx, JS::HandleValue v) {
     /* Do nothing */
 }
 #endif /* JS_DEBUG */
 class JS_PUBLIC_API(AutoGCRooter) {
   public:
     AutoGCRooter(JSContext *cx, ptrdiff_t tag);
     AutoGCRooter(js::ContextFriendFields *cx, ptrdiff_t tag);
     ~AutoGCRooter() {
         JS_ASSERT(this == *stackTop);
         *stackTop = down;
     }
     /* Implemented in gc/RootMarking.cpp. */
     inline void trace(JSTracer *trc);
     static void traceAll(JSTracer *trc);
     static void traceAllWrappers(JSTracer *trc);
   protected:
     AutoGCRooter * const down;
     /*
      * Discriminates actual subclass of this being used.  If non-negative, the
      * subclass roots an array of values of the length stored in this field.
      * If negative, meaning is indicated by the corresponding value in the enum
      * below.  Any other negative value indicates some deeper problem such as
      * memory corruption.
      */
     ptrdiff_t tag_;
     enum {
         VALARRAY =     -2, /* js::AutoValueArray */
         PARSER =       -3, /* js::frontend::Parser */
         SHAPEVECTOR =  -4, /* js::AutoShapeVector */
         IDARRAY =      -6, /* js::AutoIdArray */
         DESCRIPTORS =  -7, /* js::AutoPropDescArrayRooter */
         ID =           -9, /* js::AutoIdRooter */
         VALVECTOR =   -10, /* js::AutoValueVector */
         IDVECTOR =    -13, /* js::AutoIdVector */
         OBJVECTOR =   -14, /* js::AutoObjectVector */
         STRINGVECTOR =-15, /* js::AutoStringVector */
         SCRIPTVECTOR =-16, /* js::AutoScriptVector */
         NAMEVECTOR =  -17, /* js::AutoNameVector */
         HASHABLEVALUE=-18, /* js::HashableValue */
         IONMASM =     -19, /* js::jit::MacroAssembler */
         IONALLOC =    -20, /* js::jit::AutoTempAllocatorRooter */
         WRAPVECTOR =  -21, /* js::AutoWrapperVector */
         WRAPPER =     -22, /* js::AutoWrapperRooter */
         OBJOBJHASHMAP=-23, /* js::AutoObjectObjectHashMap */
         OBJU32HASHMAP=-24, /* js::AutoObjectUnsigned32HashMap */
         OBJHASHSET =  -25, /* js::AutoObjectHashSet */
         JSONPARSER =  -26, /* js::JSONParser */
         CUSTOM =      -27, /* js::CustomAutoRooter */
         FUNVECTOR =   -28  /* js::AutoFunctionVector */
     };
   private:
     AutoGCRooter ** const stackTop;
     /* No copy or assignment semantics. */
     AutoGCRooter(AutoGCRooter &ida) MOZ_DELETE;
     void operator=(AutoGCRooter &ida) MOZ_DELETE;
 };
 /* AutoValueArray roots an internal fixed-size array of Values. */
 template <size_t N>
 class AutoValueArray : public AutoGCRooter
 {
     const size_t length_;
     Value elements_[N];
   public:
     AutoValueArray(JSContext *cx
                    MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, VALARRAY), length_(N)
     {
         /* Always initialize in case we GC before assignment. */
         mozilla::PodArrayZero(elements_);
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     unsigned length() const { return length_; }
     const Value *begin() const { return elements_; }
     Value *begin() { return elements_; }
     HandleValue operator[](unsigned i) const {
         JS_ASSERT(i < N);
         return HandleValue::fromMarkedLocation(&elements_[i]);
     }
     MutableHandleValue operator[](unsigned i) {
         JS_ASSERT(i < N);
         return MutableHandleValue::fromMarkedLocation(&elements_[i]);
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 template<class T>
 class AutoVectorRooter : protected AutoGCRooter
 {
     typedef js::Vector<T, 8> VectorImpl;
     VectorImpl vector;
   public:
     explicit AutoVectorRooter(JSContext *cx, ptrdiff_t tag
                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, tag), vector(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     explicit AutoVectorRooter(js::ContextFriendFields *cx, ptrdiff_t tag
                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, tag), vector(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     typedef T ElementType;
     typedef typename VectorImpl::Range Range;
     size_t length() const { return vector.length(); }
     bool empty() const { return vector.empty(); }
     bool append(const T &v) { return vector.append(v); }
     bool append(const T *ptr, size_t len) { return vector.append(ptr, len); }
     bool appendAll(const AutoVectorRooter<T> &other) {
         return vector.appendAll(other.vector);
     }
     bool insert(T *p, const T &val) { return vector.insert(p, val); }
     /* For use when space has already been reserved. */
     void infallibleAppend(const T &v) { vector.infallibleAppend(v); }
     void popBack() { vector.popBack(); }
     T popCopy() { return vector.popCopy(); }
     bool growBy(size_t inc) {
         size_t oldLength = vector.length();
         if (!vector.growByUninitialized(inc))
             return false;
         makeRangeGCSafe(oldLength);
         return true;
     }
     bool resize(size_t newLength) {
         size_t oldLength = vector.length();
         if (newLength <= oldLength) {
             vector.shrinkBy(oldLength - newLength);
             return true;
         }
         if (!vector.growByUninitialized(newLength - oldLength))
             return false;
         makeRangeGCSafe(oldLength);
         return true;
     }
     void clear() { vector.clear(); }
     bool reserve(size_t newLength) {
         return vector.reserve(newLength);
     }
     T &operator[](size_t i) { return vector[i]; }
     const T &operator[](size_t i) const { return vector[i]; }
     JS::MutableHandle<T> handleAt(size_t i) {
         return JS::MutableHandle<T>::fromMarkedLocation(&vector[i]);
     }
     JS::Handle<T> handleAt(size_t i) const {
         return JS::Handle<T>::fromMarkedLocation(&vector[i]);
     }
     const T *begin() const { return vector.begin(); }
     T *begin() { return vector.begin(); }
     const T *end() const { return vector.end(); }
     T *end() { return vector.end(); }
     Range all() { return vector.all(); }
     const T &back() const { return vector.back(); }
     friend void AutoGCRooter::trace(JSTracer *trc);
   private:
     void makeRangeGCSafe(size_t oldLength) {
         T *t = vector.begin() + oldLength;
         for (size_t i = oldLength; i < vector.length(); ++i, ++t)
             memset(t, 0, sizeof(T));
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 template<class Key, class Value>
 class AutoHashMapRooter : protected AutoGCRooter
 {
   private:
     typedef js::HashMap<Key, Value> HashMapImpl;
   public:
     explicit AutoHashMapRooter(JSContext *cx, ptrdiff_t tag
                                MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, tag), map(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     typedef Key KeyType;
     typedef Value ValueType;
     typedef typename HashMapImpl::Entry Entry;
     typedef typename HashMapImpl::Lookup Lookup;
     typedef typename HashMapImpl::Ptr Ptr;
     typedef typename HashMapImpl::AddPtr AddPtr;
     bool init(uint32_t len = 16) {
         return map.init(len);
     }
     bool initialized() const {
         return map.initialized();
     }
     Ptr lookup(const Lookup &l) const {
         return map.lookup(l);
     }
     void remove(Ptr p) {
         map.remove(p);
     }
     AddPtr lookupForAdd(const Lookup &l) const {
         return map.lookupForAdd(l);
     }
     template<typename KeyInput, typename ValueInput>
     bool add(AddPtr &p, const KeyInput &k, const ValueInput &v) {
         return map.add(p, k, v);
     }
     bool add(AddPtr &p, const Key &k) {
         return map.add(p, k);
     }
     template<typename KeyInput, typename ValueInput>
     bool relookupOrAdd(AddPtr &p, const KeyInput &k, const ValueInput &v) {
         return map.relookupOrAdd(p, k, v);
     }
     typedef typename HashMapImpl::Range Range;
     Range all() const {
         return map.all();
     }
     typedef typename HashMapImpl::Enum Enum;
     void clear() {
         map.clear();
     }
     void finish() {
         map.finish();
     }
     bool empty() const {
         return map.empty();
     }
     uint32_t count() const {
         return map.count();
     }
     size_t capacity() const {
         return map.capacity();
     }
     size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
         return map.sizeOfExcludingThis(mallocSizeOf);
     }
     size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
         return map.sizeOfIncludingThis(mallocSizeOf);
     }
     unsigned generation() const {
         return map.generation();
     }
     /************************************************** Shorthand operations */
     bool has(const Lookup &l) const {
         return map.has(l);
     }
     template<typename KeyInput, typename ValueInput>
     bool put(const KeyInput &k, const ValueInput &v) {
         return map.put(k, v);
     }
     template<typename KeyInput, typename ValueInput>
     bool putNew(const KeyInput &k, const ValueInput &v) {
         return map.putNew(k, v);
     }
     Ptr lookupWithDefault(const Key &k, const Value &defaultValue) {
         return map.lookupWithDefault(k, defaultValue);
     }
     void remove(const Lookup &l) {
         map.remove(l);
     }
     friend void AutoGCRooter::trace(JSTracer *trc);
   private:
     AutoHashMapRooter(const AutoHashMapRooter &hmr) MOZ_DELETE;
     AutoHashMapRooter &operator=(const AutoHashMapRooter &hmr) MOZ_DELETE;
     HashMapImpl map;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 template<class T>
 class AutoHashSetRooter : protected AutoGCRooter
 {
   private:
     typedef js::HashSet<T> HashSetImpl;
   public:
     explicit AutoHashSetRooter(JSContext *cx, ptrdiff_t tag
                                MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, tag), set(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     typedef typename HashSetImpl::Lookup Lookup;
     typedef typename HashSetImpl::Ptr Ptr;
     typedef typename HashSetImpl::AddPtr AddPtr;
     bool init(uint32_t len = 16) {
         return set.init(len);
     }
     bool initialized() const {
         return set.initialized();
     }
     Ptr lookup(const Lookup &l) const {
         return set.lookup(l);
     }
     void remove(Ptr p) {
         set.remove(p);
     }
     AddPtr lookupForAdd(const Lookup &l) const {
         return set.lookupForAdd(l);
     }
     bool add(AddPtr &p, const T &t) {
         return set.add(p, t);
     }
     bool relookupOrAdd(AddPtr &p, const Lookup &l, const T &t) {
         return set.relookupOrAdd(p, l, t);
     }
     typedef typename HashSetImpl::Range Range;
     Range all() const {
         return set.all();
     }
     typedef typename HashSetImpl::Enum Enum;
     void clear() {
         set.clear();
     }
     void finish() {
         set.finish();
     }
     bool empty() const {
         return set.empty();
     }
     uint32_t count() const {
         return set.count();
     }
     size_t capacity() const {
         return set.capacity();
     }
     size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
         return set.sizeOfExcludingThis(mallocSizeOf);
     }
     size_t sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf) const {
         return set.sizeOfIncludingThis(mallocSizeOf);
     }
     unsigned generation() const {
         return set.generation();
     }
     /************************************************** Shorthand operations */
     bool has(const Lookup &l) const {
         return set.has(l);
     }
     bool put(const T &t) {
         return set.put(t);
     }
     bool putNew(const T &t) {
         return set.putNew(t);
     }
     void remove(const Lookup &l) {
         set.remove(l);
     }
     friend void AutoGCRooter::trace(JSTracer *trc);
   private:
     AutoHashSetRooter(const AutoHashSetRooter &hmr) MOZ_DELETE;
     AutoHashSetRooter &operator=(const AutoHashSetRooter &hmr) MOZ_DELETE;
     HashSetImpl set;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class MOZ_STACK_CLASS AutoValueVector : public AutoVectorRooter<Value>
 {
   public:
     explicit AutoValueVector(JSContext *cx
                              MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<Value>(cx, VALVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class AutoIdVector : public AutoVectorRooter<jsid>
 {
   public:
     explicit AutoIdVector(JSContext *cx
                           MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<jsid>(cx, IDVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class AutoObjectVector : public AutoVectorRooter<JSObject *>
 {
   public:
     explicit AutoObjectVector(JSContext *cx
                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<JSObject *>(cx, OBJVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class AutoFunctionVector : public AutoVectorRooter<JSFunction *>
 {
   public:
     explicit AutoFunctionVector(JSContext *cx
                                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<JSFunction *>(cx, FUNVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     explicit AutoFunctionVector(js::ContextFriendFields *cx
                                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<JSFunction *>(cx, FUNVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 class AutoScriptVector : public AutoVectorRooter<JSScript *>
 {
   public:
     explicit AutoScriptVector(JSContext *cx
                               MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
         : AutoVectorRooter<JSScript *>(cx, SCRIPTVECTOR)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 /*
  * Cutsom rooting behavior for internal and external clients.
  */
 class JS_PUBLIC_API(CustomAutoRooter) : private AutoGCRooter
 {
   public:
     template <typename CX>
     explicit CustomAutoRooter(CX *cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, CUSTOM)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     friend void AutoGCRooter::trace(JSTracer *trc);
   protected:
     /* Supplied by derived class to trace roots. */
     virtual void trace(JSTracer *trc) = 0;
   private:
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 /* A handle to an array of rooted values. */
 class HandleValueArray
 {
     const size_t length_;
     const Value * const elements_;
     HandleValueArray(size_t len, const Value *elements) : length_(len), elements_(elements) {}
   public:
     HandleValueArray(const RootedValue& value) : length_(1), elements_(value.address()) {}
     HandleValueArray(const AutoValueVector& values)
       : length_(values.length()), elements_(values.begin()) {}
     template <size_t N>
     HandleValueArray(const AutoValueArray<N>& values) : length_(N), elements_(values.begin()) {}
     /* CallArgs must already be rooted somewhere up the stack. */
     HandleValueArray(const JS::CallArgs& args) : length_(args.length()), elements_(args.array()) {}
     /* Use with care! Only call this if the data is guaranteed to be marked. */
     static HandleValueArray fromMarkedLocation(size_t len, const Value *elements) {
         return HandleValueArray(len, elements);
     }
     static HandleValueArray subarray(const HandleValueArray& values, size_t startIndex, size_t len) {
         JS_ASSERT(startIndex + len <= values.length());
         return HandleValueArray(len, values.begin() + startIndex);
     }
     static HandleValueArray empty() {
         return HandleValueArray(0, nullptr);
     }
     size_t length() const { return length_; }
     const Value *begin() const { return elements_; }
     HandleValue operator[](size_t i) const {
         JS_ASSERT(i < length_);
         return HandleValue::fromMarkedLocation(&elements_[i]);
     }
 };
 }  /* namespace JS */
 /************************************************************************/
 struct JSFreeOp {
   private:
     JSRuntime   *runtime_;
   protected:
     JSFreeOp(JSRuntime *rt)
       : runtime_(rt) { }
   public:
     JSRuntime *runtime() const {
         return runtime_;
     }
 };
 /* Callbacks and their arguments. */
 /************************************************************************/
 typedef enum JSContextOp {
     JSCONTEXT_NEW,
     JSCONTEXT_DESTROY
 } JSContextOp;
 /*
  * The possible values for contextOp when the runtime calls the callback are:
  *   JSCONTEXT_NEW      JS_NewContext successfully created a new JSContext
  *                      instance. The callback can initialize the instance as
  *                      required. If the callback returns false, the instance
  *                      will be destroyed and JS_NewContext returns null. In
  *                      this case the callback is not called again.
  *   JSCONTEXT_DESTROY  One of JS_DestroyContext* methods is called. The
  *                      callback may perform its own cleanup and must always
  *                      return true.
  *   Any other value    For future compatibility the callback must do nothing
  *                      and return true in this case.
  */
 typedef bool
 (* JSContextCallback)(JSContext *cx, unsigned contextOp, void *data);
 typedef enum JSGCStatus {
     JSGC_BEGIN,
     JSGC_END
 } JSGCStatus;
 typedef void
 (* JSGCCallback)(JSRuntime *rt, JSGCStatus status, void *data);
 typedef enum JSFinalizeStatus {
     /*
      * Called when preparing to sweep a group of compartments, before anything
      * has been swept.  The collector will not yield to the mutator before
      * calling the callback with JSFINALIZE_GROUP_END status.
      */
     JSFINALIZE_GROUP_START,
     /*
      * Called when preparing to sweep a group of compartments. Weak references
      * to unmarked things have been removed and things that are not swept
      * incrementally have been finalized at this point.  The collector may yield
      * to the mutator after this point.
      */
     JSFINALIZE_GROUP_END,
     /*
      * Called at the end of collection when everything has been swept.
      */
     JSFINALIZE_COLLECTION_END
 } JSFinalizeStatus;
 typedef void
 (* JSFinalizeCallback)(JSFreeOp *fop, JSFinalizeStatus status, bool isCompartment);
 typedef bool
 (* JSInterruptCallback)(JSContext *cx);
 typedef void
 (* JSErrorReporter)(JSContext *cx, const char *message, JSErrorReport *report);
 #ifdef MOZ_TRACE_JSCALLS
 typedef void
 (* JSFunctionCallback)(const JSFunction *fun,
                        const JSScript *scr,
                        const JSContext *cx,
                        int entering);
 #endif
 /*
  * Possible exception types. These types are part of a JSErrorFormatString
  * structure. They define which error to throw in case of a runtime error.
  * JSEXN_NONE marks an unthrowable error.
  */
 typedef enum JSExnType {
     JSEXN_NONE = -1,
       JSEXN_ERR,
         JSEXN_INTERNALERR,
         JSEXN_EVALERR,
         JSEXN_RANGEERR,
         JSEXN_REFERENCEERR,
         JSEXN_SYNTAXERR,
         JSEXN_TYPEERR,
         JSEXN_URIERR,
         JSEXN_LIMIT
 } JSExnType;
 typedef struct JSErrorFormatString {
     /* The error format string in ASCII. */
     const char *format;
     /* The number of arguments to expand in the formatted error message. */
     uint16_t argCount;
     /* One of the JSExnType constants above. */
     int16_t exnType;
 } JSErrorFormatString;
 typedef const JSErrorFormatString *
 (* JSErrorCallback)(void *userRef, const char *locale,
                     const unsigned errorNumber);
 typedef bool
 (* JSLocaleToUpperCase)(JSContext *cx, JS::HandleString src, JS::MutableHandleValue rval);
 typedef bool
 (* JSLocaleToLowerCase)(JSContext *cx, JS::HandleString src, JS::MutableHandleValue rval);
 typedef bool
 (* JSLocaleCompare)(JSContext *cx, JS::HandleString src1, JS::HandleString src2,
                     JS::MutableHandleValue rval);
 typedef bool
 (* JSLocaleToUnicode)(JSContext *cx, const char *src, JS::MutableHandleValue rval);
 /*
  * Callback used to ask the embedding for the cross compartment wrapper handler
  * that implements the desired prolicy for this kind of object in the
  * destination compartment. |obj| is the object to be wrapped. If |existing| is
  * non-nullptr, it will point to an existing wrapper object that should be
  * re-used if possible. |existing| is guaranteed to be a cross-compartment
  * wrapper with a lazily-defined prototype and the correct global. It is
  * guaranteed not to wrap a function.
  */
 typedef JSObject *
 (* JSWrapObjectCallback)(JSContext *cx, JS::HandleObject existing, JS::HandleObject obj,
                          JS::HandleObject proto, JS::HandleObject parent,
                          unsigned flags);
 /*
  * Callback used by the wrap hook to ask the embedding to prepare an object
  * for wrapping in a context. This might include unwrapping other wrappers
  * or even finding a more suitable object for the new compartment.
  */
 typedef JSObject *
 (* JSPreWrapCallback)(JSContext *cx, JS::HandleObject scope, JS::HandleObject obj,
                       unsigned flags);
 struct JSWrapObjectCallbacks
 {
     JSWrapObjectCallback wrap;
     JSPreWrapCallback preWrap;
 };
 typedef void
 (* JSDestroyCompartmentCallback)(JSFreeOp *fop, JSCompartment *compartment);
 typedef void
 (* JSZoneCallback)(JS::Zone *zone);
 typedef void
 (* JSCompartmentNameCallback)(JSRuntime *rt, JSCompartment *compartment,
                               char *buf, size_t bufsize);
 /************************************************************************/
 static MOZ_ALWAYS_INLINE jsval
 JS_NumberValue(double d)
 {
     int32_t i;
     d = JS::CanonicalizeNaN(d);
     if (mozilla::NumberIsInt32(d, &i))
         return INT_TO_JSVAL(i);
     return DOUBLE_TO_JSVAL(d);
 }
 /************************************************************************/
 JS_PUBLIC_API(bool)
 JS_StringHasBeenInterned(JSContext *cx, JSString *str);
 /*
  * Only JSStrings that have been interned via the JSAPI can be turned into
  * jsids by API clients.
  *
  * N.B. if a jsid is backed by a string which has not been interned, that
  * string must be appropriately rooted to avoid being collected by the GC.
  */
 JS_PUBLIC_API(jsid)
 INTERNED_STRING_TO_JSID(JSContext *cx, JSString *str);
 /*
  * Returns true iff the given jsval is immune to GC and can be used across
  * multiple JSRuntimes without requiring any conversion API.
  */
 static MOZ_ALWAYS_INLINE bool
 JSVAL_IS_UNIVERSAL(jsval v)
 {
     return !JSVAL_IS_GCTHING(v);
 }
 namespace JS {
 class AutoIdRooter : private AutoGCRooter
 {
   public:
     explicit AutoIdRooter(JSContext *cx, jsid aId = INT_TO_JSID(0)
                           MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, ID), id_(aId)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     jsid id() {
         return id_;
     }
     jsid * addr() {
         return &id_;
     }
     friend void AutoGCRooter::trace(JSTracer *trc);
   private:
     jsid id_;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 // Container class for passing in script source buffers to the JS engine.  This
 // not only groups the buffer and length values, it also provides a way to
 // optionally pass ownership of the buffer to the JS engine without copying.
 // Rules for use:
 //
 //  1) The data array must be allocated with js_malloc() or js_realloc() if
 //     ownership is being granted to the SourceBufferHolder.
 //  2) If ownership is not given to the SourceBufferHolder, then the memory
 //     must be kept alive until the JS compilation is complete.
 //  3) Any code calling SourceBufferHolder::take() must guarantee to keep the
 //     memory alive until JS compilation completes.  Normally only the JS
 //     engine should be calling take().
 //
 // Example use:
 //
 //    size_t length = 512;
 //    jschar* chars = static_cast<jschar*>(js_malloc(sizeof(jschar) * length));
 //    JS::SourceBufferHolder srcBuf(chars, length, JS::SourceBufferHolder::GiveOwnership);
 //    JS::Compile(cx, obj, options, srcBuf);
 //
 class MOZ_STACK_CLASS SourceBufferHolder MOZ_FINAL
 {
   public:
     enum Ownership {
       NoOwnership,
       GiveOwnership
     };
     SourceBufferHolder(const jschar *data, size_t dataLength, Ownership ownership)
       : data_(data),
         length_(dataLength),
         ownsChars_(ownership == GiveOwnership)
     {
         // Ensure that null buffers properly return an unowned, empty,
         // null-terminated string.
         static const jschar NullChar_ = 0;
         if (!get()) {
             data_ = &NullChar_;
             length_ = 0;
             ownsChars_ = false;
         }
     }
     ~SourceBufferHolder() {
         if (ownsChars_)
             js_free(const_cast<jschar *>(data_));
     }
     // Access the underlying source buffer without affecting ownership.
     const jschar *get() const { return data_; }
     // Length of the source buffer in jschars (not bytes)
     size_t length() const { return length_; }
     // Returns true if the SourceBufferHolder owns the buffer and will free
     // it upon destruction.  If true, it is legal to call take().
     bool ownsChars() const { return ownsChars_; }
     // Retrieve and take ownership of the underlying data buffer.  The caller
     // is now responsible for calling js_free() on the returned value, *but only
     // after JS script compilation has completed*.
     //
     // After the buffer has been taken the SourceBufferHolder functions as if
     // it had been constructed on an unowned buffer;  get() and length() still
     // work.  In order for this to be safe the taken buffer must be kept alive
     // until after JS script compilation completes as noted above.
     //
     // Note, it's the caller's responsibility to check ownsChars() before taking
     // the buffer.  Taking and then free'ing an unowned buffer will have dire
     // consequences.
     jschar *take() {
         JS_ASSERT(ownsChars_);
         ownsChars_ = false;
         return const_cast<jschar *>(data_);
     }
   private:
     SourceBufferHolder(SourceBufferHolder &) MOZ_DELETE;
     SourceBufferHolder &operator=(SourceBufferHolder &) MOZ_DELETE;
     const jschar *data_;
     size_t length_;
     bool ownsChars_;
 };
 } /* namespace JS */
 /************************************************************************/
 /* Property attributes, set in JSPropertySpec and passed to API functions. */
 #define JSPROP_ENUMERATE        0x01    /* property is visible to for/in loop */
 #define JSPROP_READONLY         0x02    /* not settable: assignment is no-op.
                                            This flag is only valid when neither
                                            JSPROP_GETTER nor JSPROP_SETTER is
                                            set. */
 #define JSPROP_PERMANENT        0x04    /* property cannot be deleted */
 #define JSPROP_NATIVE_ACCESSORS 0x08    /* set in JSPropertyDescriptor.flags
                                            if getters/setters are JSNatives */
 #define JSPROP_GETTER           0x10    /* property holds getter function */
 #define JSPROP_SETTER           0x20    /* property holds setter function */
 #define JSPROP_SHARED           0x40    /* don't allocate a value slot for this
                                            property; don't copy the property on
                                            set of the same-named property in an
                                            object that delegates to a prototype
                                            containing this property */
 #define JSPROP_INDEX            0x80    /* name is actually (int) index */
 #define JSFUN_STUB_GSOPS       0x200    /* use JS_PropertyStub getter/setter
                                            instead of defaulting to class gsops
                                            for property holding function */
 #define JSFUN_CONSTRUCTOR      0x400    /* native that can be called as a ctor */
 /*
  * Specify a generic native prototype methods, i.e., methods of a class
  * prototype that are exposed as static methods taking an extra leading
  * argument: the generic |this| parameter.
  *
  * If you set this flag in a JSFunctionSpec struct's flags initializer, then
  * that struct must live at least as long as the native static method object
  * created due to this flag by JS_DefineFunctions or JS_InitClass.  Typically
  * JSFunctionSpec structs are allocated in static arrays.
  */
 #define JSFUN_GENERIC_NATIVE   0x800
 #define JSFUN_FLAGS_MASK       0xe00    /* | of all the JSFUN_* flags */
 /*
  * The first call to JS_CallOnce by any thread in a process will call 'func'.
  * Later calls to JS_CallOnce with the same JSCallOnceType object will be
  * suppressed.
  *
  * Equivalently: each distinct JSCallOnceType object will allow one JS_CallOnce
  * to invoke its JSInitCallback.
  */
 extern JS_PUBLIC_API(bool)
 JS_CallOnce(JSCallOnceType *once, JSInitCallback func);
 /* Microseconds since the epoch, midnight, January 1, 1970 UTC. */
 extern JS_PUBLIC_API(int64_t)
 JS_Now(void);
 /* Don't want to export data, so provide accessors for non-inline jsvals. */
 extern JS_PUBLIC_API(jsval)
 JS_GetNaNValue(JSContext *cx);
 extern JS_PUBLIC_API(jsval)
 JS_GetNegativeInfinityValue(JSContext *cx);
 extern JS_PUBLIC_API(jsval)
 JS_GetPositiveInfinityValue(JSContext *cx);
 extern JS_PUBLIC_API(jsval)
 JS_GetEmptyStringValue(JSContext *cx);
 extern JS_PUBLIC_API(JSString *)
 JS_GetEmptyString(JSRuntime *rt);
 /*
  * Format is a string of the following characters (spaces are insignificant),
  * specifying the tabulated type conversions:
  *
  *   b      bool            Boolean
  *   c      uint16_t/jschar ECMA uint16_t, Unicode char
  *   i      int32_t         ECMA int32_t
  *   j      int32_t         ECMA int32_t (used to be different)
  *   u      uint32_t        ECMA uint32_t
  *   d      double          IEEE double
  *   I      double          Integral IEEE double
  *   S      JSString *      Unicode string, accessed by a JSString pointer
  *   W      jschar *        Unicode character vector, 0-terminated (W for wide)
  *   o      JSObject *      Object reference
  *   f      JSFunction *    Function private
  *   v      jsval           Argument value (no conversion)
  *   *      N/A             Skip this argument (no vararg)
  *   /      N/A             End of required arguments
  *
  * The variable argument list after format must consist of &b, &c, &s, e.g.,
  * where those variables have the types given above.  For the pointer types
  * char *, JSString *, and JSObject *, the pointed-at memory returned belongs
  * to the JS runtime, not to the calling native code.  The runtime promises
  * to keep this memory valid so long as argv refers to allocated stack space
  * (so long as the native function is active).
  *
  * Fewer arguments than format specifies may be passed only if there is a /
  * in format after the last required argument specifier and argc is at least
  * the number of required arguments.  More arguments than format specifies
  * may be passed without error; it is up to the caller to deal with trailing
  * unconverted arguments.
  */
 extern JS_PUBLIC_API(bool)
 JS_ConvertArguments(JSContext *cx, const JS::CallArgs &args, const char *format, ...);
 #ifdef va_start
 extern JS_PUBLIC_API(bool)
 JS_ConvertArgumentsVA(JSContext *cx, const JS::CallArgs &args, const char *format,
                       va_list ap);
 #endif
 extern JS_PUBLIC_API(bool)
 JS_ConvertValue(JSContext *cx, JS::HandleValue v, JSType type, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_ValueToObject(JSContext *cx, JS::HandleValue v, JS::MutableHandleObject objp);
 extern JS_PUBLIC_API(JSFunction *)
 JS_ValueToFunction(JSContext *cx, JS::HandleValue v);
 extern JS_PUBLIC_API(JSFunction *)
 JS_ValueToConstructor(JSContext *cx, JS::HandleValue v);
 extern JS_PUBLIC_API(JSString *)
 JS_ValueToSource(JSContext *cx, JS::Handle<JS::Value> v);
 namespace js {
 /*
  * DO NOT CALL THIS.  Use JS::ToNumber
  */
 extern JS_PUBLIC_API(bool)
 ToNumberSlow(JSContext *cx, JS::Value v, double *dp);
 /*
  * DO NOT CALL THIS. Use JS::ToBoolean
  */
 extern JS_PUBLIC_API(bool)
 ToBooleanSlow(JS::HandleValue v);
 /*
  * DO NOT CALL THIS. Use JS::ToString
  */
 extern JS_PUBLIC_API(JSString*)
 ToStringSlow(JSContext *cx, JS::HandleValue v);
 } /* namespace js */
 namespace JS {
 /* ES5 9.3 ToNumber. */
 MOZ_ALWAYS_INLINE bool
 ToNumber(JSContext *cx, HandleValue v, double *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isNumber()) {
         *out = v.toNumber();
         return true;
     }
     return js::ToNumberSlow(cx, v, out);
 }
 MOZ_ALWAYS_INLINE bool
 ToBoolean(HandleValue v)
 {
     if (v.isBoolean())
         return v.toBoolean();
     if (v.isInt32())
         return v.toInt32() != 0;
     if (v.isNullOrUndefined())
         return false;
     if (v.isDouble()) {
         double d = v.toDouble();
         return !mozilla::IsNaN(d) && d != 0;
     }
     /* The slow path handles strings and objects. */
     return js::ToBooleanSlow(v);
 }
 MOZ_ALWAYS_INLINE JSString*
 ToString(JSContext *cx, HandleValue v)
 {
     if (v.isString())
         return v.toString();
     return js::ToStringSlow(cx, v);
 }
 } /* namespace JS */
 extern JS_PUBLIC_API(bool)
 JS_DoubleIsInt32(double d, int32_t *ip);
 extern JS_PUBLIC_API(int32_t)
 JS_DoubleToInt32(double d);
 extern JS_PUBLIC_API(uint32_t)
 JS_DoubleToUint32(double d);
 namespace js {
 /* DO NOT CALL THIS. Use JS::ToUint16. */
 extern JS_PUBLIC_API(bool)
 ToUint16Slow(JSContext *cx, JS::HandleValue v, uint16_t *out);
 /* DO NOT CALL THIS. Use JS::ToInt32. */
 extern JS_PUBLIC_API(bool)
 ToInt32Slow(JSContext *cx, JS::HandleValue v, int32_t *out);
 /* DO NOT CALL THIS. Use JS::ToUint32. */
 extern JS_PUBLIC_API(bool)
 ToUint32Slow(JSContext *cx, JS::HandleValue v, uint32_t *out);
 /* DO NOT CALL THIS. Use JS::ToInt64. */
 extern JS_PUBLIC_API(bool)
 ToInt64Slow(JSContext *cx, JS::HandleValue v, int64_t *out);
 /* DO NOT CALL THIS. Use JS::ToUint64. */
 extern JS_PUBLIC_API(bool)
 ToUint64Slow(JSContext *cx, JS::HandleValue v, uint64_t *out);
 } /* namespace js */
 namespace JS {
 MOZ_ALWAYS_INLINE bool
 ToUint16(JSContext *cx, JS::HandleValue v, uint16_t *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isInt32()) {
         *out = uint16_t(v.toInt32());
         return true;
     }
     return js::ToUint16Slow(cx, v, out);
 }
 MOZ_ALWAYS_INLINE bool
 ToInt32(JSContext *cx, JS::HandleValue v, int32_t *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isInt32()) {
         *out = v.toInt32();
         return true;
     }
     return js::ToInt32Slow(cx, v, out);
 }
 MOZ_ALWAYS_INLINE bool
 ToUint32(JSContext *cx, JS::HandleValue v, uint32_t *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isInt32()) {
         *out = uint32_t(v.toInt32());
         return true;
     }
     return js::ToUint32Slow(cx, v, out);
 }
 MOZ_ALWAYS_INLINE bool
 ToInt64(JSContext *cx, JS::HandleValue v, int64_t *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isInt32()) {
         *out = int64_t(v.toInt32());
         return true;
     }
     return js::ToInt64Slow(cx, v, out);
 }
 MOZ_ALWAYS_INLINE bool
 ToUint64(JSContext *cx, JS::HandleValue v, uint64_t *out)
 {
     AssertArgumentsAreSane(cx, v);
     if (v.isInt32()) {
         /* Account for sign extension of negatives into the longer 64bit space. */
         *out = uint64_t(int64_t(v.toInt32()));
         return true;
     }
     return js::ToUint64Slow(cx, v, out);
 }
 } /* namespace JS */
 extern JS_PUBLIC_API(JSType)
 JS_TypeOfValue(JSContext *cx, JS::Handle<JS::Value> v);
 extern JS_PUBLIC_API(const char *)
 JS_GetTypeName(JSContext *cx, JSType type);
 extern JS_PUBLIC_API(bool)
 JS_StrictlyEqual(JSContext *cx, jsval v1, jsval v2, bool *equal);
 extern JS_PUBLIC_API(bool)
 JS_LooselyEqual(JSContext *cx, JS::Handle<JS::Value> v1, JS::Handle<JS::Value> v2, bool *equal);
 extern JS_PUBLIC_API(bool)
 JS_SameValue(JSContext *cx, jsval v1, jsval v2, bool *same);
 /* True iff fun is the global eval function. */
 extern JS_PUBLIC_API(bool)
 JS_IsBuiltinEvalFunction(JSFunction *fun);
 /* True iff fun is the Function constructor. */
 extern JS_PUBLIC_API(bool)
 JS_IsBuiltinFunctionConstructor(JSFunction *fun);
 /************************************************************************/
 /*
  * Initialization, locking, contexts, and memory allocation.
  *
  * It is important that the first runtime and first context be created in a
  * single-threaded fashion, otherwise the behavior of the library is undefined.
  * See: http://developer.mozilla.org/en/docs/Category:JSAPI_Reference
  */
 typedef enum JSUseHelperThreads
 {
     JS_NO_HELPER_THREADS,
     JS_USE_HELPER_THREADS
 } JSUseHelperThreads;
 /**
  * Initialize SpiderMonkey, returning true only if initialization succeeded.
  * Once this method has succeeded, it is safe to call JS_NewRuntime and other
  * JSAPI methods.
  *
  * This method must be called before any other JSAPI method is used on any
  * thread.  Once it has been used, it is safe to call any JSAPI method, and it
  * remains safe to do so until JS_ShutDown is correctly called.
  *
  * It is currently not possible to initialize SpiderMonkey multiple times (that
  * is, calling JS_Init/JSAPI methods/JS_ShutDown in that order, then doing so
  * again).  This restriction may eventually be lifted.
  */
 extern JS_PUBLIC_API(bool)
 JS_Init(void);
 /**
  * Destroy free-standing resources allocated by SpiderMonkey, not associated
  * with any runtime, context, or other structure.
  *
  * This method should be called after all other JSAPI data has been properly
  * cleaned up: every new runtime must have been destroyed, every new context
  * must have been destroyed, and so on.  Calling this method before all other
  * resources have been destroyed has undefined behavior.
  *
  * Failure to call this method, at present, has no adverse effects other than
  * leaking memory.  This may not always be the case; it's recommended that all
  * embedders call this method when all other JSAPI operations have completed.
  *
  * It is currently not possible to initialize SpiderMonkey multiple times (that
  * is, calling JS_Init/JSAPI methods/JS_ShutDown in that order, then doing so
  * again).  This restriction may eventually be lifted.
  */
 extern JS_PUBLIC_API(void)
 JS_ShutDown(void);
 extern JS_PUBLIC_API(JSRuntime *)
 JS_NewRuntime(uint32_t maxbytes, JSUseHelperThreads useHelperThreads,
               JSRuntime *parentRuntime = nullptr);
 extern JS_PUBLIC_API(void)
 JS_DestroyRuntime(JSRuntime *rt);
 // These are equivalent to ICU's |UMemAllocFn|, |UMemReallocFn|, and
 // |UMemFreeFn| types.  The first argument (called |context| in the ICU docs)
 // will always be nullptr, and should be ignored.
 typedef void *(*JS_ICUAllocFn)(const void *, size_t size);
 typedef void *(*JS_ICUReallocFn)(const void *, void *p, size_t size);
 typedef void (*JS_ICUFreeFn)(const void *, void *p);
 // This function can be used to track memory used by ICU.
 // Do not use it unless you know what you are doing!
 extern JS_PUBLIC_API(bool)
 JS_SetICUMemoryFunctions(JS_ICUAllocFn allocFn, JS_ICUReallocFn reallocFn, JS_ICUFreeFn freeFn);
 JS_PUBLIC_API(void *)
 JS_GetRuntimePrivate(JSRuntime *rt);
 extern JS_PUBLIC_API(JSRuntime *)
 JS_GetRuntime(JSContext *cx);
 extern JS_PUBLIC_API(JSRuntime *)
 JS_GetParentRuntime(JSContext *cx);
 JS_PUBLIC_API(void)
 JS_SetRuntimePrivate(JSRuntime *rt, void *data);
 extern JS_PUBLIC_API(void)
 JS_BeginRequest(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_EndRequest(JSContext *cx);
 extern JS_PUBLIC_API(bool)
 JS_IsInRequest(JSRuntime *rt);
 namespace js {
 void
 AssertHeapIsIdle(JSRuntime *rt);
 void
 AssertHeapIsIdle(JSContext *cx);
 } /* namespace js */
 class JSAutoRequest
 {
   public:
     JSAutoRequest(JSContext *cx
                   MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : mContext(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
         JS_BeginRequest(mContext);
     }
     ~JSAutoRequest() {
         JS_EndRequest(mContext);
     }
   protected:
     JSContext *mContext;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 #if 0
   private:
     static void *operator new(size_t) CPP_THROW_NEW { return 0; };
     static void operator delete(void *, size_t) { };
 #endif
 };
 class JSAutoCheckRequest
 {
   public:
     JSAutoCheckRequest(JSContext *cx
                        MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
     {
 #if defined JS_THREADSAFE && defined JS_DEBUG
         mContext = cx;
         JS_ASSERT(JS_IsInRequest(JS_GetRuntime(cx)));
 #endif
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     ~JSAutoCheckRequest() {
 #if defined JS_THREADSAFE && defined JS_DEBUG
         JS_ASSERT(JS_IsInRequest(JS_GetRuntime(mContext)));
 #endif
     }
   private:
 #if defined JS_THREADSAFE && defined JS_DEBUG
     JSContext *mContext;
 #endif
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 extern JS_PUBLIC_API(void)
 JS_SetContextCallback(JSRuntime *rt, JSContextCallback cxCallback, void *data);
 extern JS_PUBLIC_API(JSContext *)
 JS_NewContext(JSRuntime *rt, size_t stackChunkSize);
 extern JS_PUBLIC_API(void)
 JS_DestroyContext(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_DestroyContextNoGC(JSContext *cx);
 extern JS_PUBLIC_API(void *)
 JS_GetContextPrivate(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_SetContextPrivate(JSContext *cx, void *data);
 extern JS_PUBLIC_API(void *)
 JS_GetSecondContextPrivate(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_SetSecondContextPrivate(JSContext *cx, void *data);
 extern JS_PUBLIC_API(JSRuntime *)
 JS_GetRuntime(JSContext *cx);
 extern JS_PUBLIC_API(JSContext *)
 JS_ContextIterator(JSRuntime *rt, JSContext **iterp);
 extern JS_PUBLIC_API(JSVersion)
 JS_GetVersion(JSContext *cx);
 // Mutate the version on the compartment. This is generally discouraged, but
 // necessary to support the version mutation in the js and xpc shell command
 // set.
 //
 // It would be nice to put this in jsfriendapi, but the linkage requirements
 // of the shells make that impossible.
 JS_PUBLIC_API(void)
 JS_SetVersionForCompartment(JSCompartment *compartment, JSVersion version);
 extern JS_PUBLIC_API(const char *)
 JS_VersionToString(JSVersion version);
 extern JS_PUBLIC_API(JSVersion)
 JS_StringToVersion(const char *string);
 namespace JS {
 class JS_PUBLIC_API(RuntimeOptions) {
   public:
     RuntimeOptions()
       : baseline_(false),
         ion_(false),
         asmJS_(false)
     {
     }
     bool baseline() const { return baseline_; }
     RuntimeOptions &setBaseline(bool flag) {
         baseline_ = flag;
         return *this;
     }
     RuntimeOptions &toggleBaseline() {
         baseline_ = !baseline_;
         return *this;
     }
     bool ion() const { return ion_; }
     RuntimeOptions &setIon(bool flag) {
         ion_ = flag;
         return *this;
     }
     RuntimeOptions &toggleIon() {
         ion_ = !ion_;
         return *this;
     }
     bool asmJS() const { return asmJS_; }
     RuntimeOptions &setAsmJS(bool flag) {
         asmJS_ = flag;
         return *this;
     }
     RuntimeOptions &toggleAsmJS() {
         asmJS_ = !asmJS_;
         return *this;
     }
   private:
     bool baseline_ : 1;
     bool ion_ : 1;
     bool asmJS_ : 1;
 };
 JS_PUBLIC_API(RuntimeOptions &)
 RuntimeOptionsRef(JSRuntime *rt);
 JS_PUBLIC_API(RuntimeOptions &)
 RuntimeOptionsRef(JSContext *cx);
 class JS_PUBLIC_API(ContextOptions) {
   public:
     ContextOptions()
       : extraWarnings_(false),
         werror_(false),
         varObjFix_(false),
         privateIsNSISupports_(false),
         dontReportUncaught_(false),
         noDefaultCompartmentObject_(false),
         noScriptRval_(false),
         strictMode_(false),
         cloneSingletons_(false)
     {
     }
     bool extraWarnings() const { return extraWarnings_; }
     ContextOptions &setExtraWarnings(bool flag) {
         extraWarnings_ = flag;
         return *this;
     }
     ContextOptions &toggleExtraWarnings() {
         extraWarnings_ = !extraWarnings_;
         return *this;
     }
     bool werror() const { return werror_; }
     ContextOptions &setWerror(bool flag) {
         werror_ = flag;
         return *this;
     }
     ContextOptions &toggleWerror() {
         werror_ = !werror_;
         return *this;
     }
     bool varObjFix() const { return varObjFix_; }
     ContextOptions &setVarObjFix(bool flag) {
         varObjFix_ = flag;
         return *this;
     }
     ContextOptions &toggleVarObjFix() {
         varObjFix_ = !varObjFix_;
         return *this;
     }
     bool privateIsNSISupports() const { return privateIsNSISupports_; }
     ContextOptions &setPrivateIsNSISupports(bool flag) {
         privateIsNSISupports_ = flag;
         return *this;
     }
     ContextOptions &togglePrivateIsNSISupports() {
         privateIsNSISupports_ = !privateIsNSISupports_;
         return *this;
     }
     bool dontReportUncaught() const { return dontReportUncaught_; }
     ContextOptions &setDontReportUncaught(bool flag) {
         dontReportUncaught_ = flag;
         return *this;
     }
     ContextOptions &toggleDontReportUncaught() {
         dontReportUncaught_ = !dontReportUncaught_;
         return *this;
     }
     bool noDefaultCompartmentObject() const { return noDefaultCompartmentObject_; }
     ContextOptions &setNoDefaultCompartmentObject(bool flag) {
         noDefaultCompartmentObject_ = flag;
         return *this;
     }
     ContextOptions &toggleNoDefaultCompartmentObject() {
         noDefaultCompartmentObject_ = !noDefaultCompartmentObject_;
         return *this;
     }
     bool noScriptRval() const { return noScriptRval_; }
     ContextOptions &setNoScriptRval(bool flag) {
         noScriptRval_ = flag;
         return *this;
     }
     ContextOptions &toggleNoScriptRval() {
         noScriptRval_ = !noScriptRval_;
         return *this;
     }
     bool strictMode() const { return strictMode_; }
     ContextOptions &setStrictMode(bool flag) {
         strictMode_ = flag;
         return *this;
     }
     ContextOptions &toggleStrictMode() {
         strictMode_ = !strictMode_;
         return *this;
     }
     bool cloneSingletons() const { return cloneSingletons_; }
     ContextOptions &setCloneSingletons(bool flag) {
         cloneSingletons_ = flag;
         return *this;
     }
     ContextOptions &toggleCloneSingletons() {
         cloneSingletons_ = !cloneSingletons_;
         return *this;
     }
   private:
     bool extraWarnings_ : 1;
     bool werror_ : 1;
     bool varObjFix_ : 1;
     bool privateIsNSISupports_ : 1;
     bool dontReportUncaught_ : 1;
     bool noDefaultCompartmentObject_ : 1;
     bool noScriptRval_ : 1;
     bool strictMode_ : 1;
     bool cloneSingletons_ : 1;
 };
 JS_PUBLIC_API(ContextOptions &)
 ContextOptionsRef(JSContext *cx);
 class JS_PUBLIC_API(AutoSaveContextOptions) {
   public:
     AutoSaveContextOptions(JSContext *cx)
       : cx_(cx),
         oldOptions_(ContextOptionsRef(cx_))
     {
     }
     ~AutoSaveContextOptions()
     {
         ContextOptionsRef(cx_) = oldOptions_;
     }
   private:
     JSContext *cx_;
     JS::ContextOptions oldOptions_;
 };
 } /* namespace JS */
 extern JS_PUBLIC_API(const char *)
 JS_GetImplementationVersion(void);
 extern JS_PUBLIC_API(void)
 JS_SetDestroyCompartmentCallback(JSRuntime *rt, JSDestroyCompartmentCallback callback);
 extern JS_PUBLIC_API(void)
 JS_SetDestroyZoneCallback(JSRuntime *rt, JSZoneCallback callback);
 extern JS_PUBLIC_API(void)
 JS_SetSweepZoneCallback(JSRuntime *rt, JSZoneCallback callback);
 extern JS_PUBLIC_API(void)
 JS_SetCompartmentNameCallback(JSRuntime *rt, JSCompartmentNameCallback callback);
 extern JS_PUBLIC_API(void)
 JS_SetWrapObjectCallbacks(JSRuntime *rt, const JSWrapObjectCallbacks *callbacks);
 extern JS_PUBLIC_API(void)
 JS_SetCompartmentPrivate(JSCompartment *compartment, void *data);
 extern JS_PUBLIC_API(void *)
 JS_GetCompartmentPrivate(JSCompartment *compartment);
 extern JS_PUBLIC_API(void)
 JS_SetZoneUserData(JS::Zone *zone, void *data);
 extern JS_PUBLIC_API(void *)
 JS_GetZoneUserData(JS::Zone *zone);
 extern JS_PUBLIC_API(bool)
 JS_WrapObject(JSContext *cx, JS::MutableHandleObject objp);
 extern JS_PUBLIC_API(bool)
 JS_WrapValue(JSContext *cx, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_WrapId(JSContext *cx, JS::MutableHandleId idp);
 extern JS_PUBLIC_API(JSObject *)
 JS_TransplantObject(JSContext *cx, JS::HandleObject origobj, JS::HandleObject target);
 extern JS_PUBLIC_API(bool)
 JS_RefreshCrossCompartmentWrappers(JSContext *cx, JS::Handle<JSObject*> obj);
 /*
  * At any time, a JSContext has a current (possibly-nullptr) compartment.
  * Compartments are described in:
  *
  *   developer.mozilla.org/en-US/docs/SpiderMonkey/SpiderMonkey_compartments
  *
  * The current compartment of a context may be changed. The preferred way to do
  * this is with JSAutoCompartment:
  *
  *   void foo(JSContext *cx, JSObject *obj) {
  *     // in some compartment 'c'
  *     {
  *       JSAutoCompartment ac(cx, obj);  // constructor enters
  *       // in the compartment of 'obj'
  *     }                                 // destructor leaves
  *     // back in compartment 'c'
  *   }
  *
  * For more complicated uses that don't neatly fit in a C++ stack frame, the
  * compartment can entered and left using separate function calls:
  *
  *   void foo(JSContext *cx, JSObject *obj) {
  *     // in 'oldCompartment'
  *     JSCompartment *oldCompartment = JS_EnterCompartment(cx, obj);
  *     // in the compartment of 'obj'
  *     JS_LeaveCompartment(cx, oldCompartment);
  *     // back in 'oldCompartment'
  *   }
  *
  * Note: these calls must still execute in a LIFO manner w.r.t all other
  * enter/leave calls on the context. Furthermore, only the return value of a
  * JS_EnterCompartment call may be passed as the 'oldCompartment' argument of
  * the corresponding JS_LeaveCompartment call.
  */
 class JS_PUBLIC_API(JSAutoCompartment)
 {
     JSContext *cx_;
     JSCompartment *oldCompartment_;
   public:
     JSAutoCompartment(JSContext *cx, JSObject *target);
     JSAutoCompartment(JSContext *cx, JSScript *target);
     ~JSAutoCompartment();
 };
 class JS_PUBLIC_API(JSAutoNullCompartment)
 {
     JSContext *cx_;
     JSCompartment *oldCompartment_;
   public:
     JSAutoNullCompartment(JSContext *cx);
     ~JSAutoNullCompartment();
 };
 /* NB: This API is infallible; a nullptr return value does not indicate error. */
 extern JS_PUBLIC_API(JSCompartment *)
 JS_EnterCompartment(JSContext *cx, JSObject *target);
 extern JS_PUBLIC_API(void)
 JS_LeaveCompartment(JSContext *cx, JSCompartment *oldCompartment);
 typedef void (*JSIterateCompartmentCallback)(JSRuntime *rt, void *data, JSCompartment *compartment);
 /*
  * This function calls |compartmentCallback| on every compartment.  Beware that
  * there is no guarantee that the compartment will survive after the callback
  * returns.
  */
 extern JS_PUBLIC_API(void)
 JS_IterateCompartments(JSRuntime *rt, void *data,
                        JSIterateCompartmentCallback compartmentCallback);
 /*
  * Initialize standard JS class constructors, prototypes, and any top-level
  * functions and constants associated with the standard classes (e.g. isNaN
  * for Number).
  *
  * NB: This sets cx's global object to obj if it was null.
  */
 extern JS_PUBLIC_API(bool)
 JS_InitStandardClasses(JSContext *cx, JS::Handle<JSObject*> obj);
 /*
  * Resolve id, which must contain either a string or an int, to a standard
  * class name in obj if possible, defining the class's constructor and/or
  * prototype and storing true in *resolved.  If id does not name a standard
  * class or a top-level property induced by initializing a standard class,
  * store false in *resolved and just return true.  Return false on error,
  * as usual for bool result-typed API entry points.
  *
  * This API can be called directly from a global object class's resolve op,
  * to define standard classes lazily.  The class's enumerate op should call
  * JS_EnumerateStandardClasses(cx, obj), to define eagerly during for..in
  * loops any classes not yet resolved lazily.
  */
 extern JS_PUBLIC_API(bool)
 JS_ResolveStandardClass(JSContext *cx, JS::HandleObject obj, JS::HandleId id, bool *resolved);
 extern JS_PUBLIC_API(bool)
 JS_EnumerateStandardClasses(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(bool)
 JS_GetClassObject(JSContext *cx, JSProtoKey key, JS::MutableHandle<JSObject*> objp);
 extern JS_PUBLIC_API(bool)
 JS_GetClassPrototype(JSContext *cx, JSProtoKey key, JS::MutableHandle<JSObject*> objp);
 namespace JS {
 /*
  * Determine if the given object is an instance or prototype for a standard
  * class. If so, return the associated JSProtoKey. If not, return JSProto_Null.
  */
 extern JS_PUBLIC_API(JSProtoKey)
 IdentifyStandardInstance(JSObject *obj);
 extern JS_PUBLIC_API(JSProtoKey)
 IdentifyStandardPrototype(JSObject *obj);
 extern JS_PUBLIC_API(JSProtoKey)
 IdentifyStandardInstanceOrPrototype(JSObject *obj);
 } /* namespace JS */
 extern JS_PUBLIC_API(JSProtoKey)
 JS_IdToProtoKey(JSContext *cx, JS::HandleId id);
 /*
  * Returns the original value of |Function.prototype| from the global object in
  * which |forObj| was created.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_GetFunctionPrototype(JSContext *cx, JS::HandleObject forObj);
 /*
  * Returns the original value of |Object.prototype| from the global object in
  * which |forObj| was created.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_GetObjectPrototype(JSContext *cx, JS::HandleObject forObj);
 /*
  * Returns the original value of |Array.prototype| from the global object in
  * which |forObj| was created.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_GetArrayPrototype(JSContext *cx, JS::HandleObject forObj);
 extern JS_PUBLIC_API(JSObject *)
 JS_GetGlobalForObject(JSContext *cx, JSObject *obj);
 extern JS_PUBLIC_API(bool)
 JS_IsGlobalObject(JSObject *obj);
 /*
  * May return nullptr, if |c| never had a global (e.g. the atoms compartment),
  * or if |c|'s global has been collected.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_GetGlobalForCompartmentOrNull(JSContext *cx, JSCompartment *c);
 namespace JS {
 extern JS_PUBLIC_API(JSObject *)
 CurrentGlobalOrNull(JSContext *cx);
 }
 /*
  * Initialize the 'Reflect' object on a global object.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_InitReflect(JSContext *cx, JS::HandleObject global);
 #ifdef JS_HAS_CTYPES
 /*
  * Initialize the 'ctypes' object on a global variable 'obj'. The 'ctypes'
  * object will be sealed.
  */
 extern JS_PUBLIC_API(bool)
 JS_InitCTypesClass(JSContext *cx, JS::HandleObject global);
 /*
  * Convert a unicode string 'source' of length 'slen' to the platform native
  * charset, returning a null-terminated string allocated with JS_malloc. On
  * failure, this function should report an error.
  */
 typedef char *
 (* JSCTypesUnicodeToNativeFun)(JSContext *cx, const jschar *source, size_t slen);
 /*
  * Set of function pointers that ctypes can use for various internal functions.
  * See JS_SetCTypesCallbacks below. Providing nullptr for a function is safe,
  * and will result in the applicable ctypes functionality not being available.
  */
 struct JSCTypesCallbacks {
     JSCTypesUnicodeToNativeFun unicodeToNative;
 };
 typedef struct JSCTypesCallbacks JSCTypesCallbacks;
 /*
  * Set the callbacks on the provided 'ctypesObj' object. 'callbacks' should be a
  * pointer to static data that exists for the lifetime of 'ctypesObj', but it
  * may safely be altered after calling this function and without having
  * to call this function again.
  */
 extern JS_PUBLIC_API(void)
 JS_SetCTypesCallbacks(JSObject *ctypesObj, JSCTypesCallbacks *callbacks);
 #endif
 typedef bool
 (* JSEnumerateDiagnosticMemoryCallback)(void *ptr, size_t length);
 /*
  * Enumerate memory regions that contain diagnostic information
  * intended to be included in crash report minidumps.
  */
 extern JS_PUBLIC_API(void)
 JS_EnumerateDiagnosticMemoryRegions(JSEnumerateDiagnosticMemoryCallback callback);
 extern JS_PUBLIC_API(void *)
 JS_malloc(JSContext *cx, size_t nbytes);
 extern JS_PUBLIC_API(void *)
 JS_realloc(JSContext *cx, void *p, size_t nbytes);
 /*
  * A wrapper for js_free(p) that may delay js_free(p) invocation as a
  * performance optimization.
  * cx may be nullptr.
  */
 extern JS_PUBLIC_API(void)
 JS_free(JSContext *cx, void *p);
 /*
  * A wrapper for js_free(p) that may delay js_free(p) invocation as a
  * performance optimization as specified by the given JSFreeOp instance.
  */
 extern JS_PUBLIC_API(void)
 JS_freeop(JSFreeOp *fop, void *p);
 extern JS_PUBLIC_API(JSFreeOp *)
 JS_GetDefaultFreeOp(JSRuntime *rt);
 extern JS_PUBLIC_API(void)
 JS_updateMallocCounter(JSContext *cx, size_t nbytes);
 extern JS_PUBLIC_API(char *)
 JS_strdup(JSContext *cx, const char *s);
 /* Duplicate a string.  Does not report an error on failure. */
 extern JS_PUBLIC_API(char *)
 JS_strdup(JSRuntime *rt, const char *s);
 namespace JS {
 /*
  * A GC root is a pointer to a jsval, JSObject * or JSString * that itself
  * points into the GC heap. JS_AddValueRoot takes a pointer to a jsval and
  * JS_AddGCThingRoot takes a pointer to a JSObject * or JString *.
  *
  * Note that, since JS_Add*Root stores the address of a variable (of type
  * jsval, JSString *, or JSObject *), that variable must live until
  * JS_Remove*Root is called to remove that variable. For example, after:
  *
  *   void some_function() {
  *     jsval v;
  *     JS_AddNamedValueRoot(cx, &v, "name");
  *
  * the caller must perform
  *
  *     JS_RemoveValueRoot(cx, &v);
  *
  * before some_function() returns.
  *
  * Also, use JS_AddNamed*Root(cx, &structPtr->memberObj, "structPtr->memberObj")
  * in preference to JS_Add*Root(cx, &structPtr->memberObj), in order to identify
  * roots by their source callsites.  This way, you can find the callsite while
  * debugging if you should fail to do JS_Remove*Root(cx, &structPtr->memberObj)
  * before freeing structPtr's memory.
  */
 extern JS_PUBLIC_API(bool)
 AddValueRoot(JSContext *cx, JS::Heap<JS::Value> *vp);
 extern JS_PUBLIC_API(bool)
 AddStringRoot(JSContext *cx, JS::Heap<JSString *> *rp);
 extern JS_PUBLIC_API(bool)
 AddObjectRoot(JSContext *cx, JS::Heap<JSObject *> *rp);
 extern JS_PUBLIC_API(bool)
 AddNamedValueRoot(JSContext *cx, JS::Heap<JS::Value> *vp, const char *name);
 extern JS_PUBLIC_API(bool)
 AddNamedValueRootRT(JSRuntime *rt, JS::Heap<JS::Value> *vp, const char *name);
 extern JS_PUBLIC_API(bool)
 AddNamedStringRoot(JSContext *cx, JS::Heap<JSString *> *rp, const char *name);
 extern JS_PUBLIC_API(bool)
 AddNamedObjectRoot(JSContext *cx, JS::Heap<JSObject *> *rp, const char *name);
 extern JS_PUBLIC_API(bool)
 AddNamedScriptRoot(JSContext *cx, JS::Heap<JSScript *> *rp, const char *name);
 extern JS_PUBLIC_API(void)
 RemoveValueRoot(JSContext *cx, JS::Heap<JS::Value> *vp);
 extern JS_PUBLIC_API(void)
 RemoveStringRoot(JSContext *cx, JS::Heap<JSString *> *rp);
 extern JS_PUBLIC_API(void)
 RemoveObjectRoot(JSContext *cx, JS::Heap<JSObject *> *rp);
 extern JS_PUBLIC_API(void)
 RemoveScriptRoot(JSContext *cx, JS::Heap<JSScript *> *rp);
 extern JS_PUBLIC_API(void)
 RemoveValueRootRT(JSRuntime *rt, JS::Heap<JS::Value> *vp);
 extern JS_PUBLIC_API(void)
 RemoveStringRootRT(JSRuntime *rt, JS::Heap<JSString *> *rp);
 extern JS_PUBLIC_API(void)
 RemoveObjectRootRT(JSRuntime *rt, JS::Heap<JSObject *> *rp);
 extern JS_PUBLIC_API(void)
 RemoveScriptRootRT(JSRuntime *rt, JS::Heap<JSScript *> *rp);
 } /* namespace JS */
 /*
  * Register externally maintained GC roots.
  *
  * traceOp: the trace operation. For each root the implementation should call
  *          JS_CallTracer whenever the root contains a traceable thing.
  * data:    the data argument to pass to each invocation of traceOp.
  */
 extern JS_PUBLIC_API(bool)
 JS_AddExtraGCRootsTracer(JSRuntime *rt, JSTraceDataOp traceOp, void *data);
 /* Undo a call to JS_AddExtraGCRootsTracer. */
 extern JS_PUBLIC_API(void)
 JS_RemoveExtraGCRootsTracer(JSRuntime *rt, JSTraceDataOp traceOp, void *data);
 #ifdef JS_DEBUG
 /*
  * Debug-only method to dump the object graph of heap-allocated things.
  *
  * fp:              file for the dump output.
  * start:           when non-null, dump only things reachable from start
  *                  thing. Otherwise dump all things reachable from the
  *                  runtime roots.
  * startKind:       trace kind of start if start is not null. Must be
  *                  JSTRACE_OBJECT when start is null.
  * thingToFind:     dump only paths in the object graph leading to thingToFind
  *                  when non-null.
  * maxDepth:        the upper bound on the number of edges to descend from the
  *                  graph roots.
  * thingToIgnore:   thing to ignore during the graph traversal when non-null.
  */
 extern JS_PUBLIC_API(bool)
 JS_DumpHeap(JSRuntime *rt, FILE *fp, void* startThing, JSGCTraceKind kind,
             void *thingToFind, size_t maxDepth, void *thingToIgnore);
 #endif
 /*
  * Garbage collector API.
  */
 extern JS_PUBLIC_API(void)
 JS_GC(JSRuntime *rt);
 extern JS_PUBLIC_API(void)
 JS_MaybeGC(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_SetGCCallback(JSRuntime *rt, JSGCCallback cb, void *data);
 extern JS_PUBLIC_API(void)
 JS_SetFinalizeCallback(JSRuntime *rt, JSFinalizeCallback cb);
 extern JS_PUBLIC_API(bool)
 JS_IsGCMarkingTracer(JSTracer *trc);
 /* For assertions only. */
 #ifdef JS_DEBUG
 extern JS_PUBLIC_API(bool)
 JS_IsMarkingGray(JSTracer *trc);
 #endif
 /*
  * JS_IsAboutToBeFinalized checks if the given object is going to be finalized
  * at the end of the current GC. When called outside of the context of a GC,
  * this function will return false. Typically this function is used on weak
  * references, where the reference should be nulled out or destroyed if the
  * given object is about to be finalized.
  *
  * The argument to JS_IsAboutToBeFinalized is an in-out param: when the
  * function returns false, the object being referenced is still alive, but the
  * garbage collector might have moved it. In this case, the reference passed
  * to JS_IsAboutToBeFinalized will be updated to the object's new location.
  * Callers of this method are responsible for updating any state that is
  * dependent on the object's address. For example, if the object's address is
  * used as a key in a hashtable, then the object must be removed and
  * re-inserted with the correct hash.
  */
 extern JS_PUBLIC_API(bool)
 JS_IsAboutToBeFinalized(JS::Heap<JSObject *> *objp);
 extern JS_PUBLIC_API(bool)
 JS_IsAboutToBeFinalizedUnbarriered(JSObject **objp);
 typedef enum JSGCParamKey {
     /* Maximum nominal heap before last ditch GC. */
     JSGC_MAX_BYTES          = 0,
     /* Number of JS_malloc bytes before last ditch GC. */
     JSGC_MAX_MALLOC_BYTES   = 1,
     /* Amount of bytes allocated by the GC. */
     JSGC_BYTES = 3,
     /* Number of times when GC was invoked. */
     JSGC_NUMBER = 4,
     /* Max size of the code cache in bytes. */
     JSGC_MAX_CODE_CACHE_BYTES = 5,
     /* Select GC mode. */
     JSGC_MODE = 6,
     /* Number of cached empty GC chunks. */
     JSGC_UNUSED_CHUNKS = 7,
     /* Total number of allocated GC chunks. */
     JSGC_TOTAL_CHUNKS = 8,
     /* Max milliseconds to spend in an incremental GC slice. */
     JSGC_SLICE_TIME_BUDGET = 9,
     /* Maximum size the GC mark stack can grow to. */
     JSGC_MARK_STACK_LIMIT = 10,
     /*
      * GCs less than this far apart in time will be considered 'high-frequency GCs'.
      * See setGCLastBytes in jsgc.cpp.
      */
     JSGC_HIGH_FREQUENCY_TIME_LIMIT = 11,
     /* Start of dynamic heap growth. */
     JSGC_HIGH_FREQUENCY_LOW_LIMIT = 12,
     /* End of dynamic heap growth. */
     JSGC_HIGH_FREQUENCY_HIGH_LIMIT = 13,
     /* Upper bound of heap growth. */
     JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MAX = 14,
     /* Lower bound of heap growth. */
     JSGC_HIGH_FREQUENCY_HEAP_GROWTH_MIN = 15,
     /* Heap growth for low frequency GCs. */
     JSGC_LOW_FREQUENCY_HEAP_GROWTH = 16,
     /*
      * If false, the heap growth factor is fixed at 3. If true, it is determined
      * based on whether GCs are high- or low- frequency.
      */
     JSGC_DYNAMIC_HEAP_GROWTH = 17,
     /* If true, high-frequency GCs will use a longer mark slice. */
     JSGC_DYNAMIC_MARK_SLICE = 18,
     /* Lower limit after which we limit the heap growth. */
     JSGC_ALLOCATION_THRESHOLD = 19,
     /*
      * We decommit memory lazily. If more than this number of megabytes is
      * available to be decommitted, then JS_MaybeGC will trigger a shrinking GC
      * to decommit it.
      */
     JSGC_DECOMMIT_THRESHOLD = 20
 } JSGCParamKey;
 extern JS_PUBLIC_API(void)
 JS_SetGCParameter(JSRuntime *rt, JSGCParamKey key, uint32_t value);
 extern JS_PUBLIC_API(uint32_t)
 JS_GetGCParameter(JSRuntime *rt, JSGCParamKey key);
 extern JS_PUBLIC_API(void)
 JS_SetGCParameterForThread(JSContext *cx, JSGCParamKey key, uint32_t value);
 extern JS_PUBLIC_API(uint32_t)
 JS_GetGCParameterForThread(JSContext *cx, JSGCParamKey key);
 extern JS_PUBLIC_API(void)
 JS_SetGCParametersBasedOnAvailableMemory(JSRuntime *rt, uint32_t availMem);
 /*
  * Create a new JSString whose chars member refers to external memory, i.e.,
  * memory requiring application-specific finalization.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_NewExternalString(JSContext *cx, const jschar *chars, size_t length,
                      const JSStringFinalizer *fin);
 /*
  * Return whether 'str' was created with JS_NewExternalString or
  * JS_NewExternalStringWithClosure.
  */
 extern JS_PUBLIC_API(bool)
 JS_IsExternalString(JSString *str);
 /*
  * Return the 'closure' arg passed to JS_NewExternalStringWithClosure or
  * nullptr if the external string was created via JS_NewExternalString.
  */
 extern JS_PUBLIC_API(const JSStringFinalizer *)
 JS_GetExternalStringFinalizer(JSString *str);
 /*
  * Set the size of the native stack that should not be exceed. To disable
  * stack size checking pass 0.
  *
  * SpiderMonkey allows for a distinction between system code (such as GCs, which
  * may incidentally be triggered by script but are not strictly performed on
  * behalf of such script), trusted script (as determined by JS_SetTrustedPrincipals),
  * and untrusted script. Each kind of code may have a different stack quota,
  * allowing embedders to keep higher-priority machinery running in the face of
  * scripted stack exhaustion by something else.
  *
  * The stack quotas for each kind of code should be monotonically descending,
  * and may be specified with this function. If 0 is passed for a given kind
  * of code, it defaults to the value of the next-highest-priority kind.
  */
 extern JS_PUBLIC_API(void)
 JS_SetNativeStackQuota(JSRuntime *cx, size_t systemCodeStackSize,
                        size_t trustedScriptStackSize = 0,
                        size_t untrustedScriptStackSize = 0);
 /************************************************************************/
 extern JS_PUBLIC_API(int)
 JS_IdArrayLength(JSContext *cx, JSIdArray *ida);
 extern JS_PUBLIC_API(jsid)
 JS_IdArrayGet(JSContext *cx, JSIdArray *ida, int index);
 extern JS_PUBLIC_API(void)
 JS_DestroyIdArray(JSContext *cx, JSIdArray *ida);
 namespace JS {
 class AutoIdArray : private AutoGCRooter
 {
   public:
     AutoIdArray(JSContext *cx, JSIdArray *ida
                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : AutoGCRooter(cx, IDARRAY), context(cx), idArray(ida)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     ~AutoIdArray() {
         if (idArray)
             JS_DestroyIdArray(context, idArray);
     }
     bool operator!() {
         return !idArray;
     }
     jsid operator[](size_t i) const {
         JS_ASSERT(idArray);
         return JS_IdArrayGet(context, idArray, i);
     }
     size_t length() const {
         return JS_IdArrayLength(context, idArray);
     }
     friend void AutoGCRooter::trace(JSTracer *trc);
     JSIdArray *steal() {
         JSIdArray *copy = idArray;
         idArray = nullptr;
         return copy;
     }
   protected:
     inline void trace(JSTracer *trc);
   private:
     JSContext *context;
     JSIdArray *idArray;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
     /* No copy or assignment semantics. */
     AutoIdArray(AutoIdArray &ida) MOZ_DELETE;
     void operator=(AutoIdArray &ida) MOZ_DELETE;
 };
 } /* namespace JS */
 extern JS_PUBLIC_API(bool)
 JS_ValueToId(JSContext *cx, JS::HandleValue v, JS::MutableHandleId idp);
 extern JS_PUBLIC_API(bool)
 JS_StringToId(JSContext *cx, JS::HandleString s, JS::MutableHandleId idp);
 extern JS_PUBLIC_API(bool)
 JS_IdToValue(JSContext *cx, jsid id, JS::MutableHandle<JS::Value> vp);
 /*
  * Invoke the [[DefaultValue]] hook (see ES5 8.6.2) with the provided hint on
  * the specified object, computing a primitive default value for the object.
  * The hint must be JSTYPE_STRING, JSTYPE_NUMBER, or JSTYPE_VOID (no hint).  On
  * success the resulting value is stored in *vp.
  */
 extern JS_PUBLIC_API(bool)
 JS_DefaultValue(JSContext *cx, JS::Handle<JSObject*> obj, JSType hint,
                 JS::MutableHandle<JS::Value> vp);
 extern JS_PUBLIC_API(bool)
 JS_PropertyStub(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                 JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_StrictPropertyStub(JSContext *cx, JS::HandleObject obj, JS::HandleId id, bool strict,
                       JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_DeletePropertyStub(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                       bool *succeeded);
 extern JS_PUBLIC_API(bool)
 JS_EnumerateStub(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(bool)
 JS_ResolveStub(JSContext *cx, JS::HandleObject obj, JS::HandleId id);
 extern JS_PUBLIC_API(bool)
 JS_ConvertStub(JSContext *cx, JS::HandleObject obj, JSType type,
                JS::MutableHandleValue vp);
 struct JSConstDoubleSpec {
     double          dval;
     const char      *name;
     uint8_t         flags;
     uint8_t         spare[3];
 };
 struct JSJitInfo;
 /*
  * Wrappers to replace {Strict,}PropertyOp for JSPropertySpecs. This will allow
  * us to pass one JSJitInfo per function with the property spec, without
  * additional field overhead.
  */
 typedef struct JSStrictPropertyOpWrapper {
     JSStrictPropertyOp  op;
     const JSJitInfo     *info;
 } JSStrictPropertyOpWrapper;
 typedef struct JSPropertyOpWrapper {
     JSPropertyOp        op;
     const JSJitInfo     *info;
 } JSPropertyOpWrapper;
 /*
  * Wrapper to do as above, but for JSNatives for JSFunctionSpecs.
  */
 typedef struct JSNativeWrapper {
     JSNative        op;
     const JSJitInfo *info;
 } JSNativeWrapper;
 /*
  * Macro static initializers which make it easy to pass no JSJitInfo as part of a
  * JSPropertySpec or JSFunctionSpec.
  */
 #define JSOP_WRAPPER(op) { {op, nullptr} }
 #define JSOP_NULLWRAPPER JSOP_WRAPPER(nullptr)
 /*
  * To define an array element rather than a named property member, cast the
  * element's index to (const char *) and initialize name with it, and set the
  * JSPROP_INDEX bit in flags.
  */
 struct JSPropertySpec {
     struct SelfHostedWrapper {
         void       *unused;
         const char *funname;
     };
     const char                  *name;
     uint8_t                     flags;
     union {
         JSPropertyOpWrapper propertyOp;
         SelfHostedWrapper   selfHosted;
     } getter;
     union {
         JSStrictPropertyOpWrapper propertyOp;
         SelfHostedWrapper         selfHosted;
     } setter;
 private:
     void StaticAsserts() {
         JS_STATIC_ASSERT(sizeof(SelfHostedWrapper) == sizeof(JSPropertyOpWrapper));
         JS_STATIC_ASSERT(sizeof(SelfHostedWrapper) == sizeof(JSStrictPropertyOpWrapper));
         JS_STATIC_ASSERT(offsetof(SelfHostedWrapper, funname) ==
                          offsetof(JSPropertyOpWrapper, info));
     }
 };
 namespace JS {
 namespace detail {
 /* NEVER DEFINED, DON'T USE.  For use by JS_CAST_NATIVE_TO only. */
 inline int CheckIsNative(JSNative native);
 /* NEVER DEFINED, DON'T USE.  For use by JS_CAST_STRING_TO only. */
 template<size_t N>
 inline int
 CheckIsCharacterLiteral(const char (&arr)[N]);
 } // namespace detail
 } // namespace JS
 #define JS_CAST_NATIVE_TO(v, To) \
   (static_cast<void>(sizeof(JS::detail::CheckIsNative(v))), \
    reinterpret_cast<To>(v))
 #define JS_CAST_STRING_TO(s, To) \
   (static_cast<void>(sizeof(JS::detail::CheckIsCharacterLiteral(s))), \
    reinterpret_cast<To>(s))
 #define JS_CHECK_ACCESSOR_FLAGS(flags) \
   (static_cast<mozilla::EnableIf<!((flags) & (JSPROP_READONLY | JSPROP_SHARED | JSPROP_NATIVE_ACCESSORS))>::Type>(0), \
    (flags))
 /*
  * JSPropertySpec uses JSAPI JSPropertyOp and JSStrictPropertyOp in function
  * signatures.  These macros encapsulate the definition of JSNative-backed
  * JSPropertySpecs, performing type-safe casts on the getter/setter functions
  * and adding the necessary property flags to trigger interpretation as
  * JSNatives.
  */
 #define JS_PSG(name, getter, flags) \
     {name, \
      uint8_t(JS_CHECK_ACCESSOR_FLAGS(flags) | JSPROP_SHARED | JSPROP_NATIVE_ACCESSORS), \
      JSOP_WRAPPER(JS_CAST_NATIVE_TO(getter, JSPropertyOp)), \
      JSOP_NULLWRAPPER}
 #define JS_PSGS(name, getter, setter, flags) \
     {name, \
      uint8_t(JS_CHECK_ACCESSOR_FLAGS(flags) | JSPROP_SHARED | JSPROP_NATIVE_ACCESSORS), \
      JSOP_WRAPPER(JS_CAST_NATIVE_TO(getter, JSPropertyOp)), \
      JSOP_WRAPPER(JS_CAST_NATIVE_TO(setter, JSStrictPropertyOp))}
 #define JS_SELF_HOSTED_GET(name, getterName, flags) \
     {name, \
      uint8_t(JS_CHECK_ACCESSOR_FLAGS(flags) | JSPROP_SHARED | JSPROP_GETTER), \
      { nullptr, JS_CAST_STRING_TO(getterName, const JSJitInfo *) }, \
      JSOP_NULLWRAPPER }
 #define JS_SELF_HOSTED_GETSET(name, getterName, setterName, flags) \
     {name, \
      uint8_t(JS_CHECK_ACCESSOR_FLAGS(flags) | JSPROP_SHARED | JSPROP_GETTER | JSPROP_SETTER), \
      { nullptr, JS_CAST_STRING_TO(getterName, const JSJitInfo *) },  \
      { nullptr, JS_CAST_STRING_TO(setterName, const JSJitInfo *) } }
 #define JS_PS_END { nullptr, 0, JSOP_NULLWRAPPER, JSOP_NULLWRAPPER }
 /*
  * To define a native function, set call to a JSNativeWrapper. To define a
  * self-hosted function, set selfHostedName to the name of a function
  * compiled during JSRuntime::initSelfHosting.
  */
 struct JSFunctionSpec {
     const char      *name;
     JSNativeWrapper call;
     uint16_t        nargs;
     uint16_t        flags;
     const char      *selfHostedName;
 };
 /*
  * Terminating sentinel initializer to put at the end of a JSFunctionSpec array
  * that's passed to JS_DefineFunctions or JS_InitClass.
  */
 #define JS_FS_END JS_FS(nullptr,nullptr,0,0)
 /*
  * Initializer macros for a JSFunctionSpec array element. JS_FN (whose name pays
  * homage to the old JSNative/JSFastNative split) simply adds the flag
  * JSFUN_STUB_GSOPS. JS_FNINFO allows the simple adding of
  * JSJitInfos. JS_SELF_HOSTED_FN declares a self-hosted function. Finally
  * JS_FNSPEC has slots for all the fields.
  */
 #define JS_FS(name,call,nargs,flags)                                          \
     JS_FNSPEC(name, call, nullptr, nargs, flags, nullptr)
 #define JS_FN(name,call,nargs,flags)                                          \
     JS_FNSPEC(name, call, nullptr, nargs, (flags) | JSFUN_STUB_GSOPS, nullptr)
 #define JS_FNINFO(name,call,info,nargs,flags)                                 \
     JS_FNSPEC(name, call, info, nargs, flags, nullptr)
 #define JS_SELF_HOSTED_FN(name,selfHostedName,nargs,flags)                    \
     JS_FNSPEC(name, nullptr, nullptr, nargs, flags, selfHostedName)
 #define JS_FNSPEC(name,call,info,nargs,flags,selfHostedName)                  \
     {name, {call, info}, nargs, flags, selfHostedName}
 extern JS_PUBLIC_API(JSObject *)
 JS_InitClass(JSContext *cx, JS::HandleObject obj, JS::HandleObject parent_proto,
              const JSClass *clasp, JSNative constructor, unsigned nargs,
              const JSPropertySpec *ps, const JSFunctionSpec *fs,
              const JSPropertySpec *static_ps, const JSFunctionSpec *static_fs);
 /*
  * Set up ctor.prototype = proto and proto.constructor = ctor with the
  * right property flags.
  */
 extern JS_PUBLIC_API(bool)
 JS_LinkConstructorAndPrototype(JSContext *cx, JS::Handle<JSObject*> ctor,
                                JS::Handle<JSObject*> proto);
 extern JS_PUBLIC_API(const JSClass *)
 JS_GetClass(JSObject *obj);
 extern JS_PUBLIC_API(bool)
 JS_InstanceOf(JSContext *cx, JS::Handle<JSObject*> obj, const JSClass *clasp, JS::CallArgs *args);
 extern JS_PUBLIC_API(bool)
 JS_HasInstance(JSContext *cx, JS::Handle<JSObject*> obj, JS::Handle<JS::Value> v, bool *bp);
 extern JS_PUBLIC_API(void *)
 JS_GetPrivate(JSObject *obj);
 extern JS_PUBLIC_API(void)
 JS_SetPrivate(JSObject *obj, void *data);
 extern JS_PUBLIC_API(void *)
 JS_GetInstancePrivate(JSContext *cx, JS::Handle<JSObject*> obj, const JSClass *clasp,
                       JS::CallArgs *args);
 extern JS_PUBLIC_API(bool)
 JS_GetPrototype(JSContext *cx, JS::HandleObject obj, JS::MutableHandleObject protop);
 extern JS_PUBLIC_API(bool)
 JS_SetPrototype(JSContext *cx, JS::HandleObject obj, JS::HandleObject proto);
 extern JS_PUBLIC_API(JSObject *)
 JS_GetParent(JSObject *obj);
 extern JS_PUBLIC_API(bool)
 JS_SetParent(JSContext *cx, JS::HandleObject obj, JS::HandleObject parent);
 extern JS_PUBLIC_API(JSObject *)
 JS_GetConstructor(JSContext *cx, JS::Handle<JSObject*> proto);
 namespace JS {
 enum ZoneSpecifier {
     FreshZone = 0,
     SystemZone = 1
 };
 class JS_PUBLIC_API(CompartmentOptions)
 {
   public:
     class Override {
       public:
         Override() : mode_(Default) {}
         bool get(bool defaultValue) const {
             if (mode_ == Default)
                 return defaultValue;
             return mode_ == ForceTrue;
         };
         void set(bool overrideValue) {
             mode_ = overrideValue ? ForceTrue : ForceFalse;
         };
         void reset() {
             mode_ = Default;
         }
       private:
         enum Mode {
             Default,
             ForceTrue,
             ForceFalse
         };
         Mode mode_;
     };
     explicit CompartmentOptions()
       : version_(JSVERSION_UNKNOWN)
       , invisibleToDebugger_(false)
       , mergeable_(false)
       , discardSource_(false)
       , traceGlobal_(nullptr)
       , singletonsAsTemplates_(true)
     {
         zone_.spec = JS::FreshZone;
     }
     JSVersion version() const { return version_; }
     CompartmentOptions &setVersion(JSVersion aVersion) {
         MOZ_ASSERT(aVersion != JSVERSION_UNKNOWN);
         version_ = aVersion;
         return *this;
     }
     // Certain scopes (i.e. XBL compilation scopes) are implementation details
     // of the embedding, and references to them should never leak out to script.
     // This flag causes the this compartment to skip firing onNewGlobalObject
     // and makes addDebuggee a no-op for this global.
     bool invisibleToDebugger() const { return invisibleToDebugger_; }
     CompartmentOptions &setInvisibleToDebugger(bool flag) {
         invisibleToDebugger_ = flag;
         return *this;
     }
     // Compartments used for off-thread compilation have their contents merged
     // into a target compartment when the compilation is finished. This is only
     // allowed if this flag is set.  The invisibleToDebugger flag must also be
     // set for such compartments.
     bool mergeable() const { return mergeable_; }
     CompartmentOptions &setMergeable(bool flag) {
         mergeable_ = flag;
         return *this;
     }
     // For certain globals, we know enough about the code that will run in them
     // that we can discard script source entirely.
     bool discardSource() const { return discardSource_; }
     CompartmentOptions &setDiscardSource(bool flag) {
         discardSource_ = flag;
         return *this;
     }
     bool cloneSingletons(JSContext *cx) const;
     Override &cloneSingletonsOverride() { return cloneSingletonsOverride_; }
     void *zonePointer() const {
         JS_ASSERT(uintptr_t(zone_.pointer) > uintptr_t(JS::SystemZone));
         return zone_.pointer;
     }
     ZoneSpecifier zoneSpecifier() const { return zone_.spec; }
     CompartmentOptions &setZone(ZoneSpecifier spec);
     CompartmentOptions &setSameZoneAs(JSObject *obj);
     void setSingletonsAsValues() {
         singletonsAsTemplates_ = false;
     }
     bool getSingletonsAsTemplates() const {
         return singletonsAsTemplates_;
     };
     CompartmentOptions &setTrace(JSTraceOp op) {
         traceGlobal_ = op;
         return *this;
     }
     JSTraceOp getTrace() const {
         return traceGlobal_;
     }
   private:
     JSVersion version_;
     bool invisibleToDebugger_;
     bool mergeable_;
     bool discardSource_;
     Override cloneSingletonsOverride_;
     union {
         ZoneSpecifier spec;
         void *pointer; // js::Zone* is not exposed in the API.
     } zone_;
     JSTraceOp traceGlobal_;
     // To XDR singletons, we need to ensure that all singletons are all used as
     // templates, by making JSOP_OBJECT return a clone of the JSScript
     // singleton, instead of returning the value which is baked in the JSScript.
     bool singletonsAsTemplates_;
 };
 JS_PUBLIC_API(CompartmentOptions &)
 CompartmentOptionsRef(JSCompartment *compartment);
 JS_PUBLIC_API(CompartmentOptions &)
 CompartmentOptionsRef(JSObject *obj);
 JS_PUBLIC_API(CompartmentOptions &)
 CompartmentOptionsRef(JSContext *cx);
 // During global creation, we fire notifications to callbacks registered
 // via the Debugger API. These callbacks are arbitrary script, and can touch
 // the global in arbitrary ways. When that happens, the global should not be
 // in a half-baked state. But this creates a problem for consumers that need
 // to set slots on the global to put it in a consistent state.
 //
 // This API provides a way for consumers to set slots atomically (immediately
 // after the global is created), before any debugger hooks are fired. It's
 // unfortunately on the clunky side, but that's the way the cookie crumbles.
 //
 // If callers have no additional state on the global to set up, they may pass
 // |FireOnNewGlobalHook| to JS_NewGlobalObject, which causes that function to
 // fire the hook as its final act before returning. Otherwise, callers should
 // pass |DontFireOnNewGlobalHook|, which means that they are responsible for
 // invoking JS_FireOnNewGlobalObject upon successfully creating the global. If
 // an error occurs and the operation aborts, callers should skip firing the
 // hook. But otherwise, callers must take care to fire the hook exactly once
 // before compiling any script in the global's scope (we have assertions in
 // place to enforce this). This lets us be sure that debugger clients never miss
 // breakpoints.
 enum OnNewGlobalHookOption {
     FireOnNewGlobalHook,
     DontFireOnNewGlobalHook
 };
 } /* namespace JS */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewGlobalObject(JSContext *cx, const JSClass *clasp, JSPrincipals *principals,
                    JS::OnNewGlobalHookOption hookOption,
                    const JS::CompartmentOptions &options = JS::CompartmentOptions());
 /*
  * Spidermonkey does not have a good way of keeping track of what compartments should be marked on
  * their own. We can mark the roots unconditionally, but marking GC things only relevant in live
  * compartments is hard. To mitigate this, we create a static trace hook, installed on each global
  * object, from which we can be sure the compartment is relevant, and mark it.
  *
  * It is still possible to specify custom trace hooks for global object classes. They can be
  * provided via the CompartmentOptions passed to JS_NewGlobalObject.
  */
 extern JS_PUBLIC_API(void)
 JS_GlobalObjectTraceHook(JSTracer *trc, JSObject *global);
 extern JS_PUBLIC_API(void)
 JS_FireOnNewGlobalObject(JSContext *cx, JS::HandleObject global);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewObject(JSContext *cx, const JSClass *clasp, JS::Handle<JSObject*> proto,
              JS::Handle<JSObject*> parent);
 /* Queries the [[Extensible]] property of the object. */
 extern JS_PUBLIC_API(bool)
 JS_IsExtensible(JSContext *cx, JS::HandleObject obj, bool *extensible);
 extern JS_PUBLIC_API(bool)
 JS_IsNative(JSObject *obj);
 extern JS_PUBLIC_API(JSRuntime *)
 JS_GetObjectRuntime(JSObject *obj);
 /*
  * Unlike JS_NewObject, JS_NewObjectWithGivenProto does not compute a default
  * proto if proto's actual parameter value is null.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewObjectWithGivenProto(JSContext *cx, const JSClass *clasp, JS::Handle<JSObject*> proto,
                            JS::Handle<JSObject*> parent);
 /*
  * Freeze obj, and all objects it refers to, recursively. This will not recurse
  * through non-extensible objects, on the assumption that those are already
  * deep-frozen.
  */
 extern JS_PUBLIC_API(bool)
 JS_DeepFreezeObject(JSContext *cx, JS::Handle<JSObject*> obj);
 /*
  * Freezes an object; see ES5's Object.freeze(obj) method.
  */
 extern JS_PUBLIC_API(bool)
 JS_FreezeObject(JSContext *cx, JS::Handle<JSObject*> obj);
 extern JS_PUBLIC_API(bool)
 JS_PreventExtensions(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(JSObject *)
 JS_New(JSContext *cx, JS::HandleObject ctor, const JS::HandleValueArray& args);
 extern JS_PUBLIC_API(JSObject *)
 JS_DefineObject(JSContext *cx, JSObject *obj, const char *name, const JSClass *clasp,
                 JSObject *proto, unsigned attrs);
 extern JS_PUBLIC_API(bool)
 JS_DefineConstDoubles(JSContext *cx, JS::HandleObject obj, const JSConstDoubleSpec *cds);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperties(JSContext *cx, JS::HandleObject obj, const JSPropertySpec *ps);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::HandleValue value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::HandleObject value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::HandleString value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, int32_t value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, uint32_t value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefineProperty(JSContext *cx, JS::HandleObject obj, const char *name, double value,
                   unsigned attrs,
                   JSPropertyOp getter = nullptr, JSStrictPropertyOp setter = nullptr);
 extern JS_PUBLIC_API(bool)
 JS_DefinePropertyById(JSContext *cx, JSObject *obj, jsid id, jsval value,
                       JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs);
 extern JS_PUBLIC_API(bool)
 JS_DefineOwnProperty(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                      JS::HandleValue descriptor, bool *bp);
 extern JS_PUBLIC_API(bool)
 JS_AlreadyHasOwnProperty(JSContext *cx, JS::HandleObject obj, const char *name,
                          bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_AlreadyHasOwnPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                              bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_HasProperty(JSContext *cx, JS::HandleObject obj, const char *name, bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_HasPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id, bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_LookupProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_LookupPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                       JS::MutableHandleValue vp);
 struct JSPropertyDescriptor {
     JSObject           *obj;
     unsigned           attrs;
     JSPropertyOp       getter;
     JSStrictPropertyOp setter;
     JS::Value          value;
     JSPropertyDescriptor()
       : obj(nullptr), attrs(0), getter(nullptr), setter(nullptr), value(JSVAL_VOID)
     {}
     void trace(JSTracer *trc);
 };
 namespace JS {
 template <typename Outer>
 class PropertyDescriptorOperations
 {
     const JSPropertyDescriptor * desc() const { return static_cast<const Outer*>(this)->extract(); }
   public:
     bool isEnumerable() const { return desc()->attrs & JSPROP_ENUMERATE; }
     bool isReadonly() const { return desc()->attrs & JSPROP_READONLY; }
     bool isPermanent() const { return desc()->attrs & JSPROP_PERMANENT; }
     bool hasNativeAccessors() const { return desc()->attrs & JSPROP_NATIVE_ACCESSORS; }
     bool hasGetterObject() const { return desc()->attrs & JSPROP_GETTER; }
     bool hasSetterObject() const { return desc()->attrs & JSPROP_SETTER; }
     bool hasGetterOrSetterObject() const { return desc()->attrs & (JSPROP_GETTER | JSPROP_SETTER); }
     bool isShared() const { return desc()->attrs & JSPROP_SHARED; }
     bool isIndex() const { return desc()->attrs & JSPROP_INDEX; }
     bool hasAttributes(unsigned attrs) const { return desc()->attrs & attrs; }
     JS::HandleObject object() const {
         return JS::HandleObject::fromMarkedLocation(&desc()->obj);
     }
     unsigned attributes() const { return desc()->attrs; }
     JSPropertyOp getter() const { return desc()->getter; }
     JSStrictPropertyOp setter() const { return desc()->setter; }
     JS::HandleObject getterObject() const {
         MOZ_ASSERT(hasGetterObject());
         return JS::HandleObject::fromMarkedLocation(
                 reinterpret_cast<JSObject *const *>(&desc()->getter));
     }
     JS::HandleObject setterObject() const {
         MOZ_ASSERT(hasSetterObject());
         return JS::HandleObject::fromMarkedLocation(
                 reinterpret_cast<JSObject *const *>(&desc()->setter));
     }
     JS::HandleValue value() const {
         return JS::HandleValue::fromMarkedLocation(&desc()->value);
     }
 };
 template <typename Outer>
 class MutablePropertyDescriptorOperations : public PropertyDescriptorOperations<Outer>
 {
     JSPropertyDescriptor * desc() { return static_cast<Outer*>(this)->extractMutable(); }
   public:
     void clear() {
         object().set(nullptr);
         setAttributes(0);
         setGetter(nullptr);
         setSetter(nullptr);
         value().setUndefined();
     }
     JS::MutableHandleObject object() {
         return JS::MutableHandleObject::fromMarkedLocation(&desc()->obj);
     }
     unsigned &attributesRef() { return desc()->attrs; }
     JSPropertyOp &getter() { return desc()->getter; }
     JSStrictPropertyOp &setter() { return desc()->setter; }
     JS::MutableHandleValue value() {
         return JS::MutableHandleValue::fromMarkedLocation(&desc()->value);
     }
     void setEnumerable() { desc()->attrs |= JSPROP_ENUMERATE; }
     void setAttributes(unsigned attrs) { desc()->attrs = attrs; }
     void setGetter(JSPropertyOp op) { desc()->getter = op; }
     void setSetter(JSStrictPropertyOp op) { desc()->setter = op; }
     void setGetterObject(JSObject *obj) { desc()->getter = reinterpret_cast<JSPropertyOp>(obj); }
     void setSetterObject(JSObject *obj) { desc()->setter = reinterpret_cast<JSStrictPropertyOp>(obj); }
 };
 } /* namespace JS */
 namespace js {
 template <>
 struct GCMethods<JSPropertyDescriptor> {
     static JSPropertyDescriptor initial() { return JSPropertyDescriptor(); }
     static ThingRootKind kind() { return THING_ROOT_PROPERTY_DESCRIPTOR; }
     static bool poisoned(const JSPropertyDescriptor &desc) {
         return (desc.obj && JS::IsPoisonedPtr(desc.obj)) ||
                (desc.attrs & JSPROP_GETTER && desc.getter && JS::IsPoisonedPtr(desc.getter)) ||
                (desc.attrs & JSPROP_SETTER && desc.setter && JS::IsPoisonedPtr(desc.setter)) ||
                (desc.value.isGCThing() && JS::IsPoisonedPtr(desc.value.toGCThing()));
     }
 };
 template <>
 class RootedBase<JSPropertyDescriptor>
   : public JS::MutablePropertyDescriptorOperations<JS::Rooted<JSPropertyDescriptor> >
 {
     friend class JS::PropertyDescriptorOperations<JS::Rooted<JSPropertyDescriptor> >;
     friend class JS::MutablePropertyDescriptorOperations<JS::Rooted<JSPropertyDescriptor> >;
     const JSPropertyDescriptor *extract() const {
         return static_cast<const JS::Rooted<JSPropertyDescriptor>*>(this)->address();
     }
     JSPropertyDescriptor *extractMutable() {
         return static_cast<JS::Rooted<JSPropertyDescriptor>*>(this)->address();
     }
 };
 template <>
 class HandleBase<JSPropertyDescriptor>
   : public JS::PropertyDescriptorOperations<JS::Handle<JSPropertyDescriptor> >
 {
     friend class JS::PropertyDescriptorOperations<JS::Handle<JSPropertyDescriptor> >;
     const JSPropertyDescriptor *extract() const {
         return static_cast<const JS::Handle<JSPropertyDescriptor>*>(this)->address();
     }
 };
 template <>
 class MutableHandleBase<JSPropertyDescriptor>
   : public JS::MutablePropertyDescriptorOperations<JS::MutableHandle<JSPropertyDescriptor> >
 {
     friend class JS::PropertyDescriptorOperations<JS::MutableHandle<JSPropertyDescriptor> >;
     friend class JS::MutablePropertyDescriptorOperations<JS::MutableHandle<JSPropertyDescriptor> >;
     const JSPropertyDescriptor *extract() const {
         return static_cast<const JS::MutableHandle<JSPropertyDescriptor>*>(this)->address();
     }
     JSPropertyDescriptor *extractMutable() {
         return static_cast<JS::MutableHandle<JSPropertyDescriptor>*>(this)->address();
     }
 };
 } /* namespace js */
 extern JS_PUBLIC_API(bool)
 JS_GetOwnPropertyDescriptorById(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                                 JS::MutableHandle<JSPropertyDescriptor> desc);
 extern JS_PUBLIC_API(bool)
 JS_GetOwnPropertyDescriptor(JSContext *cx, JS::HandleObject obj, const char *name,
                             JS::MutableHandle<JSPropertyDescriptor> desc);
 /*
  * Like JS_GetOwnPropertyDescriptorById but will return a property on
  * an object on the prototype chain (returned in desc->obj). If desc->obj is null,
  * then this property was not found on the prototype chain.
  */
 extern JS_PUBLIC_API(bool)
 JS_GetPropertyDescriptorById(JSContext *cx, JS::HandleObject obj, JS::HandleId id,
                              JS::MutableHandle<JSPropertyDescriptor> desc);
 extern JS_PUBLIC_API(bool)
 JS_GetPropertyDescriptor(JSContext *cx, JS::HandleObject obj, const char *name,
                          JS::MutableHandle<JSPropertyDescriptor> desc);
 extern JS_PUBLIC_API(bool)
 JS_GetProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_GetPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_ForwardGetPropertyTo(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleObject onBehalfOf,
                         JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_SetProperty(JSContext *cx, JS::HandleObject obj, const char *name, JS::HandleValue v);
 extern JS_PUBLIC_API(bool)
 JS_SetPropertyById(JSContext *cx, JS::HandleObject obj, JS::HandleId id, JS::HandleValue v);
 extern JS_PUBLIC_API(bool)
 JS_DeleteProperty(JSContext *cx, JS::HandleObject obj, const char *name);
 extern JS_PUBLIC_API(bool)
 JS_DeleteProperty2(JSContext *cx, JS::HandleObject obj, const char *name, bool *succeeded);
 extern JS_PUBLIC_API(bool)
 JS_DeletePropertyById(JSContext *cx, JS::HandleObject obj, jsid id);
 extern JS_PUBLIC_API(bool)
 JS_DeletePropertyById2(JSContext *cx, JS::HandleObject obj, JS::HandleId id, bool *succeeded);
 extern JS_PUBLIC_API(bool)
 JS_DefineUCProperty(JSContext *cx, JSObject *obj,
                     const jschar *name, size_t namelen, jsval value,
                     JSPropertyOp getter, JSStrictPropertyOp setter,
                     unsigned attrs);
 extern JS_PUBLIC_API(bool)
 JS_AlreadyHasOwnUCProperty(JSContext *cx, JS::HandleObject obj, const jschar *name,
                            size_t namelen, bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_HasUCProperty(JSContext *cx, JS::HandleObject obj,
                  const jschar *name, size_t namelen,
                  bool *vp);
 extern JS_PUBLIC_API(bool)
 JS_LookupUCProperty(JSContext *cx, JS::HandleObject obj,
                     const jschar *name, size_t namelen,
                     JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_GetUCProperty(JSContext *cx, JS::HandleObject obj,
                  const jschar *name, size_t namelen,
                  JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_SetUCProperty(JSContext *cx, JS::HandleObject obj,
                  const jschar *name, size_t namelen,
                  JS::HandleValue v);
 extern JS_PUBLIC_API(bool)
 JS_DeleteUCProperty2(JSContext *cx, JS::HandleObject obj, const jschar *name, size_t namelen,
                      bool *succeeded);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewArrayObject(JSContext *cx, const JS::HandleValueArray& contents);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewArrayObject(JSContext *cx, size_t length);
 extern JS_PUBLIC_API(bool)
 JS_IsArrayObject(JSContext *cx, JS::HandleValue value);
 extern JS_PUBLIC_API(bool)
 JS_IsArrayObject(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(bool)
 JS_GetArrayLength(JSContext *cx, JS::Handle<JSObject*> obj, uint32_t *lengthp);
 extern JS_PUBLIC_API(bool)
 JS_SetArrayLength(JSContext *cx, JS::Handle<JSObject*> obj, uint32_t length);
 extern JS_PUBLIC_API(bool)
 JS_DefineElement(JSContext *cx, JSObject *obj, uint32_t index, jsval value,
                  JSPropertyOp getter, JSStrictPropertyOp setter, unsigned attrs);
 extern JS_PUBLIC_API(bool)
 JS_AlreadyHasOwnElement(JSContext *cx, JS::HandleObject obj, uint32_t index, bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_HasElement(JSContext *cx, JS::HandleObject obj, uint32_t index, bool *foundp);
 extern JS_PUBLIC_API(bool)
 JS_LookupElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_GetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_ForwardGetElementTo(JSContext *cx, JS::HandleObject obj, uint32_t index,
                        JS::HandleObject onBehalfOf, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::HandleValue v);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::HandleObject v);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, JS::HandleString v);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, int32_t v);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, uint32_t v);
 extern JS_PUBLIC_API(bool)
 JS_SetElement(JSContext *cx, JS::HandleObject obj, uint32_t index, double v);
 extern JS_PUBLIC_API(bool)
 JS_DeleteElement(JSContext *cx, JS::HandleObject obj, uint32_t index);
 extern JS_PUBLIC_API(bool)
 JS_DeleteElement2(JSContext *cx, JS::HandleObject obj, uint32_t index, bool *succeeded);
 /*
  * Remove all configurable properties from the given (non-global) object and
  * assign undefined to all writable data properties.
  */
 JS_PUBLIC_API(void)
 JS_ClearNonGlobalObject(JSContext *cx, JS::HandleObject obj);
 /*
  * Assign 'undefined' to all of the object's non-reserved slots. Note: this is
  * done for all slots, regardless of the associated property descriptor.
  */
 JS_PUBLIC_API(void)
 JS_SetAllNonReservedSlotsToUndefined(JSContext *cx, JSObject *objArg);
 /*
  * Create a new array buffer with the given contents. On success, the ownership
  * is transferred to the new array buffer.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewArrayBufferWithContents(JSContext *cx, size_t nbytes, void *contents);
 /*
  * Steal the contents of the given array buffer. The array buffer has its
  * length set to 0 and its contents array cleared. The caller takes ownership
  * of the return value and must free it or transfer ownership via
  * JS_NewArrayBufferWithContents when done using it.
  */
 extern JS_PUBLIC_API(void *)
 JS_StealArrayBufferContents(JSContext *cx, JS::HandleObject obj);
 /*
  * Allocate memory that may be eventually passed to
  * JS_NewArrayBufferWithContents. |maybecx| is optional; if a non-nullptr cx is
  * given, it will be used for memory accounting and OOM reporting. |nbytes| is
  * the number of payload bytes required.
  */
 extern JS_PUBLIC_API(void *)
 JS_AllocateArrayBufferContents(JSContext *maybecx, uint32_t nbytes);
 /*
  * Reallocate memory allocated by JS_AllocateArrayBufferContents, growing or
  * shrinking it as appropriate. If oldContents is null then this behaves like
  * JS_AllocateArrayBufferContents.
  */
 extern JS_PUBLIC_API(void *)
 JS_ReallocateArrayBufferContents(JSContext *cx, uint32_t nbytes, void *oldContents, uint32_t oldNbytes);
 /*
  * Create a new mapped array buffer with the given memory mapped contents. On success,
  * the ownership is transferred to the new mapped array buffer.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewMappedArrayBufferWithContents(JSContext *cx, size_t nbytes, void *contents);
 /*
  * Create memory mapped array buffer contents.
  * Caller must take care of closing fd after calling this function.
  */
 extern JS_PUBLIC_API(void *)
 JS_CreateMappedArrayBufferContents(int fd, size_t offset, size_t length);
 /*
  * Release the allocated resource of mapped array buffer contents before the
  * object is created.
  * If a new object has been created by JS_NewMappedArrayBufferWithContents()
  * with this content, then JS_NeuterArrayBuffer() should be used instead to
  * release the resource used by the object.
  */
 extern JS_PUBLIC_API(void)
 JS_ReleaseMappedArrayBufferContents(void *contents, size_t length);
 extern JS_PUBLIC_API(JSIdArray *)
 JS_Enumerate(JSContext *cx, JS::HandleObject obj);
 /*
  * Create an object to iterate over enumerable properties of obj, in arbitrary
  * property definition order.  NB: This differs from longstanding for..in loop
  * order, which uses order of property definition in obj.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewPropertyIterator(JSContext *cx, JS::Handle<JSObject*> obj);
 /*
  * Return true on success with *idp containing the id of the next enumerable
  * property to visit using iterobj, or JSID_IS_VOID if there is no such property
  * left to visit.  Return false on error.
  */
 extern JS_PUBLIC_API(bool)
 JS_NextProperty(JSContext *cx, JS::Handle<JSObject*> iterobj, jsid *idp);
 extern JS_PUBLIC_API(jsval)
 JS_GetReservedSlot(JSObject *obj, uint32_t index);
 extern JS_PUBLIC_API(void)
 JS_SetReservedSlot(JSObject *obj, uint32_t index, jsval v);
 /************************************************************************/
 /*
  * Functions and scripts.
  */
 extern JS_PUBLIC_API(JSFunction *)
 JS_NewFunction(JSContext *cx, JSNative call, unsigned nargs, unsigned flags,
                JS::Handle<JSObject*> parent, const char *name);
 /*
  * Create the function with the name given by the id. JSID_IS_STRING(id) must
  * be true.
  */
 extern JS_PUBLIC_API(JSFunction *)
 JS_NewFunctionById(JSContext *cx, JSNative call, unsigned nargs, unsigned flags,
                    JS::Handle<JSObject*> parent, JS::Handle<jsid> id);
 namespace JS {
 extern JS_PUBLIC_API(JSFunction *)
 GetSelfHostedFunction(JSContext *cx, const char *selfHostedName, JS::Handle<jsid> id,
                       unsigned nargs);
 } /* namespace JS */
 extern JS_PUBLIC_API(JSObject *)
 JS_GetFunctionObject(JSFunction *fun);
 /*
  * Return the function's identifier as a JSString, or null if fun is unnamed.
  * The returned string lives as long as fun, so you don't need to root a saved
  * reference to it if fun is well-connected or rooted, and provided you bound
  * the use of the saved reference by fun's lifetime.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_GetFunctionId(JSFunction *fun);
 /*
  * Return a function's display name. This is the defined name if one was given
  * where the function was defined, or it could be an inferred name by the JS
  * engine in the case that the function was defined to be anonymous. This can
  * still return nullptr if a useful display name could not be inferred. The
  * same restrictions on rooting as those in JS_GetFunctionId apply.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_GetFunctionDisplayId(JSFunction *fun);
 /*
  * Return the arity (length) of fun.
  */
 extern JS_PUBLIC_API(uint16_t)
 JS_GetFunctionArity(JSFunction *fun);
 /*
  * Infallible predicate to test whether obj is a function object (faster than
  * comparing obj's class name to "Function", but equivalent unless someone has
  * overwritten the "Function" identifier with a different constructor and then
  * created instances using that constructor that might be passed in as obj).
  */
 extern JS_PUBLIC_API(bool)
 JS_ObjectIsFunction(JSContext *cx, JSObject *obj);
 extern JS_PUBLIC_API(bool)
 JS_ObjectIsCallable(JSContext *cx, JSObject *obj);
 extern JS_PUBLIC_API(bool)
 JS_IsNativeFunction(JSObject *funobj, JSNative call);
 /* Return whether the given function is a valid constructor. */
 extern JS_PUBLIC_API(bool)
 JS_IsConstructor(JSFunction *fun);
 /*
  * Bind the given callable to use the given object as "this".
  *
  * If |callable| is not callable, will throw and return nullptr.
  */
 extern JS_PUBLIC_API(JSObject*)
 JS_BindCallable(JSContext *cx, JS::Handle<JSObject*> callable, JS::Handle<JSObject*> newThis);
 extern JS_PUBLIC_API(bool)
 JS_DefineFunctions(JSContext *cx, JS::Handle<JSObject*> obj, const JSFunctionSpec *fs);
 extern JS_PUBLIC_API(JSFunction *)
 JS_DefineFunction(JSContext *cx, JS::Handle<JSObject*> obj, const char *name, JSNative call,
                   unsigned nargs, unsigned attrs);
 extern JS_PUBLIC_API(JSFunction *)
 JS_DefineUCFunction(JSContext *cx, JS::Handle<JSObject*> obj,
                     const jschar *name, size_t namelen, JSNative call,
                     unsigned nargs, unsigned attrs);
 extern JS_PUBLIC_API(JSFunction *)
 JS_DefineFunctionById(JSContext *cx, JS::Handle<JSObject*> obj, JS::Handle<jsid> id, JSNative call,
                       unsigned nargs, unsigned attrs);
 /*
  * Clone a top-level function into a new scope. This function will dynamically
  * fail if funobj was lexically nested inside some other function.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_CloneFunctionObject(JSContext *cx, JS::Handle<JSObject*> funobj, JS::Handle<JSObject*> parent);
 /*
  * Given a buffer, return false if the buffer might become a valid
  * javascript statement with the addition of more lines.  Otherwise return
  * true.  The intent is to support interactive compilation - accumulate
  * lines in a buffer until JS_BufferIsCompilableUnit is true, then pass it to
  * the compiler.
  */
 extern JS_PUBLIC_API(bool)
 JS_BufferIsCompilableUnit(JSContext *cx, JS::Handle<JSObject*> obj, const char *utf8,
                           size_t length);
 extern JS_PUBLIC_API(JSScript *)
 JS_CompileScript(JSContext *cx, JS::HandleObject obj,
                  const char *ascii, size_t length,
                  const JS::CompileOptions &options);
 extern JS_PUBLIC_API(JSScript *)
 JS_CompileUCScript(JSContext *cx, JS::HandleObject obj,
                    const jschar *chars, size_t length,
                    const JS::CompileOptions &options);
 extern JS_PUBLIC_API(JSObject *)
 JS_GetGlobalFromScript(JSScript *script);
 extern JS_PUBLIC_API(JSFunction *)
 JS_CompileFunction(JSContext *cx, JS::HandleObject obj, const char *name,
                    unsigned nargs, const char *const *argnames,
                    const char *bytes, size_t length,
                    const JS::CompileOptions &options);
 extern JS_PUBLIC_API(JSFunction *)
 JS_CompileUCFunction(JSContext *cx, JS::HandleObject obj, const char *name,
                      unsigned nargs, const char *const *argnames,
                      const jschar *chars, size_t length,
                      const JS::CompileOptions &options);
 namespace JS {
 /* Options for JavaScript compilation. */
 /*
  * In the most common use case, a CompileOptions instance is allocated on the
  * stack, and holds non-owning references to non-POD option values: strings;
  * principals; objects; and so on. The code declaring the instance guarantees
  * that such option values will outlive the CompileOptions itself: objects are
  * otherwise rooted; principals have had their reference counts bumped; strings
  * will not be freed until the CompileOptions goes out of scope. In this
  * situation, CompileOptions only refers to things others own, so it can be
  * lightweight.
  *
  * In some cases, however, we need to hold compilation options with a
  * non-stack-like lifetime. For example, JS::CompileOffThread needs to save
  * compilation options where a worker thread can find them, and then return
  * immediately. The worker thread will come along at some later point, and use
  * the options.
  *
  * The compiler itself just needs to be able to access a collection of options;
  * it doesn't care who owns them, or what's keeping them alive. It does its own
  * addrefs/copies/tracing/etc.
  *
  * So, we have a class hierarchy that reflects these three use cases:
  *
  * - ReadOnlyCompileOptions is the common base class. It can be used by code
  *   that simply needs to access options set elsewhere, like the compiler.
  *
  * - The usual CompileOptions class must be stack-allocated, and holds
  *   non-owning references to the filename, element, and so on. It's derived
  *   from ReadOnlyCompileOptions, so the compiler can use it.
  *
  * - OwningCompileOptions roots / copies / reference counts of all its values,
  *   and unroots / frees / releases them when it is destructed. It too is
  *   derived from ReadOnlyCompileOptions, so the compiler accepts it.
  */
 /*
  * The common base class for the CompileOptions hierarchy.
  *
  * Use this in code that only needs to access compilation options created
  * elsewhere, like the compiler. Don't instantiate this class (the constructor
  * is protected anyway); instead, create instances only of the derived classes:
  * CompileOptions and OwningCompileOptions.
  */
 class JS_FRIEND_API(ReadOnlyCompileOptions)
 {
     friend class CompileOptions;
   protected:
     JSPrincipals *originPrincipals_;
     const char *filename_;
     const char *introducerFilename_;
     const jschar *sourceMapURL_;
     // This constructor leaves 'version' set to JSVERSION_UNKNOWN. The structure
     // is unusable until that's set to something more specific; the derived
     // classes' constructors take care of that, in ways appropriate to their
     // purpose.
     ReadOnlyCompileOptions()
       : originPrincipals_(nullptr),
         filename_(nullptr),
         introducerFilename_(nullptr),
         sourceMapURL_(nullptr),
         version(JSVERSION_UNKNOWN),
         versionSet(false),
         utf8(false),
         lineno(1),
         column(0),
         compileAndGo(false),
         forEval(false),
         defineOnScope(true),
         noScriptRval(false),
         selfHostingMode(false),
         canLazilyParse(true),
         strictOption(false),
         extraWarningsOption(false),
         werrorOption(false),
         asmJSOption(false),
         forceAsync(false),
         installedFile(false),
         sourceIsLazy(false),
         introductionType(nullptr),
         introductionLineno(0),
         introductionOffset(0),
         hasIntroductionInfo(false)
     { }
     // Set all POD options (those not requiring reference counts, copies,
     // rooting, or other hand-holding) to their values in |rhs|.
     void copyPODOptions(const ReadOnlyCompileOptions &rhs);
   public:
     // Read-only accessors for non-POD options. The proper way to set these
     // depends on the derived type.
     JSPrincipals *originPrincipals(js::ExclusiveContext *cx) const;
     const char *filename() const { return filename_; }
     const char *introducerFilename() const { return introducerFilename_; }
     const jschar *sourceMapURL() const { return sourceMapURL_; }
     virtual JSObject *element() const = 0;
     virtual JSString *elementAttributeName() const = 0;
     virtual JSScript *introductionScript() const = 0;
     // POD options.
     JSVersion version;
     bool versionSet;
     bool utf8;
     unsigned lineno;
     unsigned column;
     bool compileAndGo;
     bool forEval;
     bool defineOnScope;
     bool noScriptRval;
     bool selfHostingMode;
     bool canLazilyParse;
     bool strictOption;
     bool extraWarningsOption;
     bool werrorOption;
     bool asmJSOption;
     bool forceAsync;
     bool installedFile;  // 'true' iff pre-compiling js file in packaged app
     bool sourceIsLazy;
     // |introductionType| is a statically allocated C string:
     // one of "eval", "Function", or "GeneratorFunction".
     const char *introductionType;
     unsigned introductionLineno;
     uint32_t introductionOffset;
     bool hasIntroductionInfo;
     // Wrap any compilation option values that need it as appropriate for
     // use from |compartment|.
     virtual bool wrap(JSContext *cx, JSCompartment *compartment) = 0;
   private:
     static JSObject * const nullObjectPtr;
     void operator=(const ReadOnlyCompileOptions &) MOZ_DELETE;
 };
 /*
  * Compilation options, with dynamic lifetime. An instance of this type
  * makes a copy of / holds / roots all dynamically allocated resources
  * (principals; elements; strings) that it refers to. Its destructor frees
  * / drops / unroots them. This is heavier than CompileOptions, below, but
  * unlike CompileOptions, it can outlive any given stack frame.
  *
  * Note that this *roots* any JS values it refers to - they're live
  * unconditionally. Thus, instances of this type can't be owned, directly
  * or indirectly, by a JavaScript object: if any value that this roots ever
  * comes to refer to the object that owns this, then the whole cycle, and
  * anything else it entrains, will never be freed.
  */
 class JS_FRIEND_API(OwningCompileOptions) : public ReadOnlyCompileOptions
 {
     JSRuntime *runtime;
     PersistentRootedObject elementRoot;
     PersistentRootedString elementAttributeNameRoot;
     PersistentRootedScript introductionScriptRoot;
   public:
     // A minimal constructor, for use with OwningCompileOptions::copy. This
     // leaves |this.version| set to JSVERSION_UNKNOWN; the instance
     // shouldn't be used until we've set that to something real (as |copy|
     // will).
     explicit OwningCompileOptions(JSContext *cx);
     ~OwningCompileOptions();
     JSObject *element() const MOZ_OVERRIDE { return elementRoot; }
     JSString *elementAttributeName() const MOZ_OVERRIDE { return elementAttributeNameRoot; }
     JSScript *introductionScript() const MOZ_OVERRIDE { return introductionScriptRoot; }
     // Set this to a copy of |rhs|. Return false on OOM.
     bool copy(JSContext *cx, const ReadOnlyCompileOptions &rhs);
     /* These setters make copies of their string arguments, and are fallible. */
     bool setFile(JSContext *cx, const char *f);
     bool setFileAndLine(JSContext *cx, const char *f, unsigned l);
     bool setSourceMapURL(JSContext *cx, const jschar *s);
     bool setIntroducerFilename(JSContext *cx, const char *s);
     /* These setters are infallible, and can be chained. */
     OwningCompileOptions &setLine(unsigned l)             { lineno = l;              return *this; }
     OwningCompileOptions &setElement(JSObject *e) {
         elementRoot = e;
         return *this;
     }
     OwningCompileOptions &setElementAttributeName(JSString *p) {
         elementAttributeNameRoot = p;
         return *this;
     }
     OwningCompileOptions &setIntroductionScript(JSScript *s) {
         introductionScriptRoot = s;
         return *this;
     }
     OwningCompileOptions &setOriginPrincipals(JSPrincipals *p) {
         if (p) JS_HoldPrincipals(p);
         if (originPrincipals_) JS_DropPrincipals(runtime, originPrincipals_);
         originPrincipals_ = p;
         return *this;
     }
     OwningCompileOptions &setVersion(JSVersion v) {
         version = v;
         versionSet = true;
         return *this;
     }
     OwningCompileOptions &setUTF8(bool u) { utf8 = u; return *this; }
     OwningCompileOptions &setColumn(unsigned c) { column = c; return *this; }
     OwningCompileOptions &setCompileAndGo(bool cng) { compileAndGo = cng; return *this; }
     OwningCompileOptions &setForEval(bool eval) { forEval = eval; return *this; }
     OwningCompileOptions &setDefineOnScope(bool define) { defineOnScope = define; return *this; }
     OwningCompileOptions &setNoScriptRval(bool nsr) { noScriptRval = nsr; return *this; }
     OwningCompileOptions &setSelfHostingMode(bool shm) { selfHostingMode = shm; return *this; }
     OwningCompileOptions &setCanLazilyParse(bool clp) { canLazilyParse = clp; return *this; }
     OwningCompileOptions &setSourceIsLazy(bool l) { sourceIsLazy = l; return *this; }
     OwningCompileOptions &setIntroductionType(const char *t) { introductionType = t; return *this; }
     bool setIntroductionInfo(JSContext *cx, const char *introducerFn, const char *intro,
                              unsigned line, JSScript *script, uint32_t offset)
     {
         if (!setIntroducerFilename(cx, introducerFn))
             return false;
         introductionType = intro;
         introductionLineno = line;
         introductionScriptRoot = script;
         introductionOffset = offset;
         hasIntroductionInfo = true;
         return true;
     }
     virtual bool wrap(JSContext *cx, JSCompartment *compartment) MOZ_OVERRIDE;
   private:
     void operator=(const CompileOptions &rhs) MOZ_DELETE;
 };
 /*
  * Compilation options stored on the stack. An instance of this type
  * simply holds references to dynamically allocated resources (element;
  * filename; source map URL) that are owned by something else. If you
  * create an instance of this type, it's up to you to guarantee that
  * everything you store in it will outlive it.
  */
 class MOZ_STACK_CLASS JS_FRIEND_API(CompileOptions) : public ReadOnlyCompileOptions
 {
     RootedObject elementRoot;
     RootedString elementAttributeNameRoot;
     RootedScript introductionScriptRoot;
   public:
     explicit CompileOptions(JSContext *cx, JSVersion version = JSVERSION_UNKNOWN);
     CompileOptions(js::ContextFriendFields *cx, const ReadOnlyCompileOptions &rhs)
       : ReadOnlyCompileOptions(), elementRoot(cx), elementAttributeNameRoot(cx),
         introductionScriptRoot(cx)
     {
         copyPODOptions(rhs);
         originPrincipals_ = rhs.originPrincipals_;
         filename_ = rhs.filename();
         sourceMapURL_ = rhs.sourceMapURL();
         elementRoot = rhs.element();
         elementAttributeNameRoot = rhs.elementAttributeName();
         introductionScriptRoot = rhs.introductionScript();
     }
     JSObject *element() const MOZ_OVERRIDE { return elementRoot; }
     JSString *elementAttributeName() const MOZ_OVERRIDE { return elementAttributeNameRoot; }
     JSScript *introductionScript() const MOZ_OVERRIDE { return introductionScriptRoot; }
     CompileOptions &setFile(const char *f) { filename_ = f; return *this; }
     CompileOptions &setLine(unsigned l) { lineno = l; return *this; }
     CompileOptions &setFileAndLine(const char *f, unsigned l) {
         filename_ = f; lineno = l; return *this;
     }
     CompileOptions &setSourceMapURL(const jschar *s) { sourceMapURL_ = s;       return *this; }
     CompileOptions &setElement(JSObject *e)          { elementRoot = e;         return *this; }
     CompileOptions &setElementAttributeName(JSString *p) {
         elementAttributeNameRoot = p;
         return *this;
     }
     CompileOptions &setIntroductionScript(JSScript *s) {
         introductionScriptRoot = s;
         return *this;
     }
     CompileOptions &setOriginPrincipals(JSPrincipals *p) {
         originPrincipals_ = p;
         return *this;
     }
     CompileOptions &setVersion(JSVersion v) {
         version = v;
         versionSet = true;
         return *this;
     }
     CompileOptions &setUTF8(bool u) { utf8 = u; return *this; }
     CompileOptions &setColumn(unsigned c) { column = c; return *this; }
     CompileOptions &setCompileAndGo(bool cng) { compileAndGo = cng; return *this; }
     CompileOptions &setForEval(bool eval) { forEval = eval; return *this; }
     CompileOptions &setDefineOnScope(bool define) { defineOnScope = define; return *this; }
     CompileOptions &setNoScriptRval(bool nsr) { noScriptRval = nsr; return *this; }
     CompileOptions &setSelfHostingMode(bool shm) { selfHostingMode = shm; return *this; }
     CompileOptions &setCanLazilyParse(bool clp) { canLazilyParse = clp; return *this; }
     CompileOptions &setSourceIsLazy(bool l) { sourceIsLazy = l; return *this; }
     CompileOptions &setIntroductionType(const char *t) { introductionType = t; return *this; }
     CompileOptions &setIntroductionInfo(const char *introducerFn, const char *intro,
                                         unsigned line, JSScript *script, uint32_t offset)
     {
         introducerFilename_ = introducerFn;
         introductionType = intro;
         introductionLineno = line;
         introductionScriptRoot = script;
         introductionOffset = offset;
         hasIntroductionInfo = true;
         return *this;
     }
     virtual bool wrap(JSContext *cx, JSCompartment *compartment) MOZ_OVERRIDE;
   private:
     void operator=(const CompileOptions &rhs) MOZ_DELETE;
 };
 /*
  * |script| will always be set. On failure, it will be set to nullptr.
  */
 extern JS_PUBLIC_API(bool)
 Compile(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
         SourceBufferHolder &srcBuf, JS::MutableHandleScript script);
 extern JS_PUBLIC_API(JSScript *)
 Compile(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
         const char *bytes, size_t length);
 extern JS_PUBLIC_API(JSScript *)
 Compile(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
         const jschar *chars, size_t length);
 extern JS_PUBLIC_API(JSScript *)
 Compile(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options, FILE *file);
 extern JS_PUBLIC_API(JSScript *)
 Compile(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options, const char *filename);
 extern JS_PUBLIC_API(bool)
 CanCompileOffThread(JSContext *cx, const ReadOnlyCompileOptions &options, size_t length);
 /*
  * Off thread compilation control flow.
  *
  * After successfully triggering an off thread compile of a script, the
  * callback will eventually be invoked with the specified data and a token
  * for the compilation. The callback will be invoked while off the main thread,
  * so must ensure that its operations are thread safe. Afterwards,
  * FinishOffThreadScript must be invoked on the main thread to get the result
  * script or nullptr. If maybecx is not specified, the resources will be freed,
  * but no script will be returned.
  *
  * The characters passed in to CompileOffThread must remain live until the
  * callback is invoked, and the resulting script will be rooted until the call
  * to FinishOffThreadScript.
  */
 extern JS_PUBLIC_API(bool)
 CompileOffThread(JSContext *cx, const ReadOnlyCompileOptions &options,
                  const jschar *chars, size_t length,
                  OffThreadCompileCallback callback, void *callbackData);
 extern JS_PUBLIC_API(JSScript *)
 FinishOffThreadScript(JSContext *maybecx, JSRuntime *rt, void *token);
 extern JS_PUBLIC_API(bool)
 CompileFunction(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
                 const char *name, unsigned nargs, const char *const *argnames,
                 SourceBufferHolder &srcBuf, JS::MutableHandleFunction fun);
 extern JS_PUBLIC_API(JSFunction *)
 CompileFunction(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
                 const char *name, unsigned nargs, const char *const *argnames,
                 const char *bytes, size_t length);
 extern JS_PUBLIC_API(JSFunction *)
 CompileFunction(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
                 const char *name, unsigned nargs, const char *const *argnames,
                 const jschar *chars, size_t length);
 } /* namespace JS */
 extern JS_PUBLIC_API(JSString *)
 JS_DecompileScript(JSContext *cx, JS::Handle<JSScript*> script, const char *name, unsigned indent);
 /*
  * API extension: OR this into indent to avoid pretty-printing the decompiled
  * source resulting from JS_DecompileFunction{,Body}.
  */
 #define JS_DONT_PRETTY_PRINT    ((unsigned)0x8000)
 extern JS_PUBLIC_API(JSString *)
 JS_DecompileFunction(JSContext *cx, JS::Handle<JSFunction*> fun, unsigned indent);
 extern JS_PUBLIC_API(JSString *)
 JS_DecompileFunctionBody(JSContext *cx, JS::Handle<JSFunction*> fun, unsigned indent);
 /*
  * NB: JS_ExecuteScript and the JS_Evaluate*Script* quadruplets use the obj
  * parameter as the initial scope chain header, the 'this' keyword value, and
  * the variables object (ECMA parlance for where 'var' and 'function' bind
  * names) of the execution context for script.
  *
  * Using obj as the variables object is problematic if obj's parent (which is
  * the scope chain link; see JS_SetParent and JS_NewObject) is not null: in
  * this case, variables created by 'var x = 0', e.g., go in obj, but variables
  * created by assignment to an unbound id, 'x = 0', go in the last object on
  * the scope chain linked by parent.
  *
  * ECMA calls that last scoping object the "global object", but note that many
  * embeddings have several such objects.  ECMA requires that "global code" be
  * executed with the variables object equal to this global object.  But these
  * JS API entry points provide freedom to execute code against a "sub-global",
  * i.e., a parented or scoped object, in which case the variables object will
  * differ from the last object on the scope chain, resulting in confusing and
  * non-ECMA explicit vs. implicit variable creation.
  *
  * Caveat embedders: unless you already depend on this buggy variables object
  * binding behavior, you should call ContextOptionsRef(cx).setVarObjFix(true)
  * for each context in the application, if you pass parented objects as the obj
  * parameter, or may ever pass such objects in the future.
  *
  * Why a runtime option?  The alternative is to add six or so new API entry
  * points with signatures matching the following six, and that doesn't seem
  * worth the code bloat cost.  Such new entry points would probably have less
  * obvious names, too, so would not tend to be used.  The JS_SetOption call,
  * OTOH, can be more easily hacked into existing code that does not depend on
  * the bug; such code can continue to use the familiar JS_EvaluateScript,
  * etc., entry points.
  */
 extern JS_PUBLIC_API(bool)
 JS_ExecuteScript(JSContext *cx, JS::HandleObject obj, JS::HandleScript script, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 JS_ExecuteScript(JSContext *cx, JS::HandleObject obj, JS::HandleScript script);
 namespace JS {
 /*
  * Like the above, but handles a cross-compartment script. If the script is
  * cross-compartment, it is cloned into the current compartment before executing.
  */
 extern JS_PUBLIC_API(bool)
 CloneAndExecuteScript(JSContext *cx, JS::Handle<JSObject*> obj, JS::Handle<JSScript*> script);
 } /* namespace JS */
 extern JS_PUBLIC_API(bool)
 JS_ExecuteScriptVersion(JSContext *cx, JS::HandleObject obj, JS::HandleScript script,
                         JS::MutableHandleValue rval, JSVersion version);
 extern JS_PUBLIC_API(bool)
 JS_ExecuteScriptVersion(JSContext *cx, JS::HandleObject obj, JS::HandleScript script,
                         JSVersion version);
 extern JS_PUBLIC_API(bool)
 JS_EvaluateScript(JSContext *cx, JS::HandleObject obj,
                   const char *bytes, unsigned length,
                   const char *filename, unsigned lineno,
                   JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 JS_EvaluateScript(JSContext *cx, JS::HandleObject obj,
                   const char *bytes, unsigned length,
                   const char *filename, unsigned lineno);
 extern JS_PUBLIC_API(bool)
 JS_EvaluateUCScript(JSContext *cx, JS::Handle<JSObject*> obj,
                     const jschar *chars, unsigned length,
                     const char *filename, unsigned lineno,
                     JS::MutableHandle<JS::Value> rval);
 namespace JS {
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          SourceBufferHolder &srcBuf, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const jschar *chars, size_t length, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const char *bytes, size_t length, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const char *filename, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          SourceBufferHolder &srcBuf);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const jschar *chars, size_t length);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const char *bytes, size_t length);
 extern JS_PUBLIC_API(bool)
 Evaluate(JSContext *cx, JS::HandleObject obj, const ReadOnlyCompileOptions &options,
          const char *filename);
 } /* namespace JS */
 extern JS_PUBLIC_API(bool)
 JS_CallFunction(JSContext *cx, JS::HandleObject obj, JS::HandleFunction fun,
                 const JS::HandleValueArray& args, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 JS_CallFunctionName(JSContext *cx, JS::HandleObject obj, const char *name,
                     const JS::HandleValueArray& args, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 JS_CallFunctionValue(JSContext *cx, JS::HandleObject obj, JS::HandleValue fval,
                      const JS::HandleValueArray& args, JS::MutableHandleValue rval);
 namespace JS {
 static inline bool
 Call(JSContext *cx, JS::HandleObject thisObj, JS::HandleFunction fun,
      const JS::HandleValueArray &args, MutableHandleValue rval)
 {
     return !!JS_CallFunction(cx, thisObj, fun, args, rval);
 }
 static inline bool
 Call(JSContext *cx, JS::HandleObject thisObj, const char *name, const JS::HandleValueArray& args,
      MutableHandleValue rval)
 {
     return !!JS_CallFunctionName(cx, thisObj, name, args, rval);
 }
 static inline bool
 Call(JSContext *cx, JS::HandleObject thisObj, JS::HandleValue fun, const JS::HandleValueArray& args,
      MutableHandleValue rval)
 {
     return !!JS_CallFunctionValue(cx, thisObj, fun, args, rval);
 }
 extern JS_PUBLIC_API(bool)
 Call(JSContext *cx, JS::HandleValue thisv, JS::HandleValue fun, const JS::HandleValueArray& args,
      MutableHandleValue rval);
 static inline bool
 Call(JSContext *cx, JS::HandleValue thisv, JS::HandleObject funObj, const JS::HandleValueArray& args,
      MutableHandleValue rval)
 {
     JS_ASSERT(funObj);
     JS::RootedValue fun(cx, JS::ObjectValue(*funObj));
     return Call(cx, thisv, fun, args, rval);
 }
 } /* namespace JS */
 /*
  * These functions allow setting an interrupt callback that will be called
  * from the JS thread some time after any thread triggered the callback using
  * JS_RequestInterruptCallback(rt).
  *
  * To schedule the GC and for other activities the engine internally triggers
  * interrupt callbacks. The embedding should thus not rely on callbacks being
  * triggered through the external API only.
  *
  * Important note: Additional callbacks can occur inside the callback handler
  * if it re-enters the JS engine. The embedding must ensure that the callback
  * is disconnected before attempting such re-entry.
  */
 extern JS_PUBLIC_API(JSInterruptCallback)
 JS_SetInterruptCallback(JSRuntime *rt, JSInterruptCallback callback);
 extern JS_PUBLIC_API(JSInterruptCallback)
 JS_GetInterruptCallback(JSRuntime *rt);
 extern JS_PUBLIC_API(void)
 JS_RequestInterruptCallback(JSRuntime *rt);
 extern JS_PUBLIC_API(bool)
 JS_IsRunning(JSContext *cx);
 /*
  * Saving and restoring frame chains.
  *
  * These two functions are used to set aside cx's call stack while that stack
  * is inactive. After a call to JS_SaveFrameChain, it looks as if there is no
  * code running on cx. Before calling JS_RestoreFrameChain, cx's call stack
  * must be balanced and all nested calls to JS_SaveFrameChain must have had
  * matching JS_RestoreFrameChain calls.
  *
  * JS_SaveFrameChain deals with cx not having any code running on it.
  */
 extern JS_PUBLIC_API(bool)
 JS_SaveFrameChain(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_RestoreFrameChain(JSContext *cx);
 #ifdef MOZ_TRACE_JSCALLS
 /*
  * The callback is expected to be quick and noninvasive. It should not
  * request interrupts, turn on debugging, or produce uncaught JS
  * exceptions. The state of the stack and registers in the context
  * cannot be relied upon, since this callback may be invoked directly
  * from either JIT. The 'entering' field means we are entering a
  * function if it is positive, leaving a function if it is zero or
  * negative.
  */
 extern JS_PUBLIC_API(void)
 JS_SetFunctionCallback(JSContext *cx, JSFunctionCallback fcb);
 extern JS_PUBLIC_API(JSFunctionCallback)
 JS_GetFunctionCallback(JSContext *cx);
 #endif /* MOZ_TRACE_JSCALLS */
 /************************************************************************/
 /*
  * Strings.
  *
  * NB: JS_NewUCString takes ownership of bytes on success, avoiding a copy;
  * but on error (signified by null return), it leaves chars owned by the
  * caller. So the caller must free bytes in the error case, if it has no use
  * for them. In contrast, all the JS_New*StringCopy* functions do not take
  * ownership of the character memory passed to them -- they copy it.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_NewStringCopyN(JSContext *cx, const char *s, size_t n);
 extern JS_PUBLIC_API(JSString *)
 JS_NewStringCopyZ(JSContext *cx, const char *s);
 extern JS_PUBLIC_API(JSString *)
 JS_InternJSString(JSContext *cx, JS::HandleString str);
 extern JS_PUBLIC_API(JSString *)
 JS_InternStringN(JSContext *cx, const char *s, size_t length);
 extern JS_PUBLIC_API(JSString *)
 JS_InternString(JSContext *cx, const char *s);
 extern JS_PUBLIC_API(JSString *)
 JS_NewUCString(JSContext *cx, jschar *chars, size_t length);
 extern JS_PUBLIC_API(JSString *)
 JS_NewUCStringCopyN(JSContext *cx, const jschar *s, size_t n);
 extern JS_PUBLIC_API(JSString *)
 JS_NewUCStringCopyZ(JSContext *cx, const jschar *s);
 extern JS_PUBLIC_API(JSString *)
 JS_InternUCStringN(JSContext *cx, const jschar *s, size_t length);
 extern JS_PUBLIC_API(JSString *)
 JS_InternUCString(JSContext *cx, const jschar *s);
 extern JS_PUBLIC_API(bool)
 JS_CompareStrings(JSContext *cx, JSString *str1, JSString *str2, int32_t *result);
 extern JS_PUBLIC_API(bool)
 JS_StringEqualsAscii(JSContext *cx, JSString *str, const char *asciiBytes, bool *match);
 extern JS_PUBLIC_API(size_t)
 JS_PutEscapedString(JSContext *cx, char *buffer, size_t size, JSString *str, char quote);
 extern JS_PUBLIC_API(bool)
 JS_FileEscapedString(FILE *fp, JSString *str, char quote);
 /*
  * Extracting string characters and length.
  *
  * While getting the length of a string is infallible, getting the chars can
  * fail. As indicated by the lack of a JSContext parameter, there are two
  * special cases where getting the chars is infallible:
  *
  * The first case is interned strings, i.e., strings from JS_InternString or
  * JSID_TO_STRING(id), using JS_GetInternedStringChars*.
  *
  * The second case is "flat" strings that have been explicitly prepared in a
  * fallible context by JS_FlattenString. To catch errors, a separate opaque
  * JSFlatString type is returned by JS_FlattenString and expected by
  * JS_GetFlatStringChars. Note, though, that this is purely a syntactic
  * distinction: the input and output of JS_FlattenString are the same actual
  * GC-thing so only one needs to be rooted. If a JSString is known to be flat,
  * JS_ASSERT_STRING_IS_FLAT can be used to make a debug-checked cast. Example:
  *
  *   // in a fallible context
  *   JSFlatString *fstr = JS_FlattenString(cx, str);
  *   if (!fstr)
  *     return false;
  *   JS_ASSERT(fstr == JS_ASSERT_STRING_IS_FLAT(str));
  *
  *   // in an infallible context, for the same 'str'
  *   const jschar *chars = JS_GetFlatStringChars(fstr)
  *   JS_ASSERT(chars);
  *
  * The CharsZ APIs guarantee that the returned array has a null character at
  * chars[length]. This can require additional copying so clients should prefer
  * APIs without CharsZ if possible. The infallible functions also return
  * null-terminated arrays. (There is no additional cost or non-Z alternative
  * for the infallible functions, so 'Z' is left out of the identifier.)
  */
 extern JS_PUBLIC_API(size_t)
 JS_GetStringLength(JSString *str);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetStringCharsAndLength(JSContext *cx, JSString *str, size_t *length);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetInternedStringChars(JSString *str);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetInternedStringCharsAndLength(JSString *str, size_t *length);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetStringCharsZ(JSContext *cx, JSString *str);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetStringCharsZAndLength(JSContext *cx, JSString *str, size_t *length);
 extern JS_PUBLIC_API(JSFlatString *)
 JS_FlattenString(JSContext *cx, JSString *str);
 extern JS_PUBLIC_API(const jschar *)
 JS_GetFlatStringChars(JSFlatString *str);
 static MOZ_ALWAYS_INLINE JSFlatString *
 JSID_TO_FLAT_STRING(jsid id)
 {
     JS_ASSERT(JSID_IS_STRING(id));
     return (JSFlatString *)(JSID_BITS(id));
 }
 static MOZ_ALWAYS_INLINE JSFlatString *
 JS_ASSERT_STRING_IS_FLAT(JSString *str)
 {
     JS_ASSERT(JS_GetFlatStringChars((JSFlatString *)str));
     return (JSFlatString *)str;
 }
 static MOZ_ALWAYS_INLINE JSString *
 JS_FORGET_STRING_FLATNESS(JSFlatString *fstr)
 {
     return (JSString *)fstr;
 }
 /*
  * Additional APIs that avoid fallibility when given a flat string.
  */
 extern JS_PUBLIC_API(bool)
 JS_FlatStringEqualsAscii(JSFlatString *str, const char *asciiBytes);
 extern JS_PUBLIC_API(size_t)
 JS_PutEscapedFlatString(char *buffer, size_t size, JSFlatString *str, char quote);
 /*
  * Create a dependent string, i.e., a string that owns no character storage,
  * but that refers to a slice of another string's chars.  Dependent strings
  * are mutable by definition, so the thread safety comments above apply.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_NewDependentString(JSContext *cx, JS::HandleString str, size_t start,
                       size_t length);
 /*
  * Concatenate two strings, possibly resulting in a rope.
  * See above for thread safety comments.
  */
 extern JS_PUBLIC_API(JSString *)
 JS_ConcatStrings(JSContext *cx, JS::HandleString left, JS::HandleString right);
 /*
  * For JS_DecodeBytes, set *dstlenp to the size of the destination buffer before
  * the call; on return, *dstlenp contains the number of jschars actually stored.
  * To determine the necessary destination buffer size, make a sizing call that
  * passes nullptr for dst.
  *
  * On errors, the functions report the error. In that case, *dstlenp contains
  * the number of characters or bytes transferred so far.  If cx is nullptr, no
  * error is reported on failure, and the functions simply return false.
  *
  * NB: This function does not store an additional zero byte or jschar after the
  * transcoded string.
  */
 JS_PUBLIC_API(bool)
 JS_DecodeBytes(JSContext *cx, const char *src, size_t srclen, jschar *dst,
                size_t *dstlenp);
 /*
  * A variation on JS_EncodeCharacters where a null terminated string is
  * returned that you are expected to call JS_free on when done.
  */
 JS_PUBLIC_API(char *)
 JS_EncodeString(JSContext *cx, JSString *str);
 /*
  * Same behavior as JS_EncodeString(), but encode into UTF-8 string
  */
 JS_PUBLIC_API(char *)
 JS_EncodeStringToUTF8(JSContext *cx, JS::HandleString str);
 /*
  * Get number of bytes in the string encoding (without accounting for a
  * terminating zero bytes. The function returns (size_t) -1 if the string
  * can not be encoded into bytes and reports an error using cx accordingly.
  */
 JS_PUBLIC_API(size_t)
 JS_GetStringEncodingLength(JSContext *cx, JSString *str);
 /*
  * Encode string into a buffer. The function does not stores an additional
  * zero byte. The function returns (size_t) -1 if the string can not be
  * encoded into bytes with no error reported. Otherwise it returns the number
  * of bytes that are necessary to encode the string. If that exceeds the
  * length parameter, the string will be cut and only length bytes will be
  * written into the buffer.
  */
 JS_PUBLIC_API(size_t)
 JS_EncodeStringToBuffer(JSContext *cx, JSString *str, char *buffer, size_t length);
 class JSAutoByteString
 {
   public:
     JSAutoByteString(JSContext *cx, JSString *str
                      MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : mBytes(JS_EncodeString(cx, str))
     {
         JS_ASSERT(cx);
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     JSAutoByteString(MOZ_GUARD_OBJECT_NOTIFIER_ONLY_PARAM)
       : mBytes(nullptr)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
     }
     ~JSAutoByteString() {
         js_free(mBytes);
     }
     /* Take ownership of the given byte array. */
     void initBytes(char *bytes) {
         JS_ASSERT(!mBytes);
         mBytes = bytes;
     }
     char *encodeLatin1(JSContext *cx, JSString *str) {
         JS_ASSERT(!mBytes);
         JS_ASSERT(cx);
         mBytes = JS_EncodeString(cx, str);
         return mBytes;
     }
     char *encodeLatin1(js::ExclusiveContext *cx, JSString *str);
     char *encodeUtf8(JSContext *cx, JS::HandleString str) {
         JS_ASSERT(!mBytes);
         JS_ASSERT(cx);
         mBytes = JS_EncodeStringToUTF8(cx, str);
         return mBytes;
     }
     void clear() {
         js_free(mBytes);
         mBytes = nullptr;
     }
     char *ptr() const {
         return mBytes;
     }
     bool operator!() const {
         return !mBytes;
     }
     size_t length() const {
         if (!mBytes)
             return 0;
         return strlen(mBytes);
     }
   private:
     char        *mBytes;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
     /* Copy and assignment are not supported. */
     JSAutoByteString(const JSAutoByteString &another);
     JSAutoByteString &operator=(const JSAutoByteString &another);
 };
 /************************************************************************/
 /*
  * JSON functions
  */
 typedef bool (* JSONWriteCallback)(const jschar *buf, uint32_t len, void *data);
 /*
  * JSON.stringify as specified by ES5.
  */
 JS_PUBLIC_API(bool)
 JS_Stringify(JSContext *cx, JS::MutableHandleValue value, JS::HandleObject replacer,
              JS::HandleValue space, JSONWriteCallback callback, void *data);
 /*
  * JSON.parse as specified by ES5.
  */
 JS_PUBLIC_API(bool)
 JS_ParseJSON(JSContext *cx, const jschar *chars, uint32_t len, JS::MutableHandleValue vp);
 JS_PUBLIC_API(bool)
 JS_ParseJSONWithReviver(JSContext *cx, const jschar *chars, uint32_t len, JS::HandleValue reviver,
                         JS::MutableHandleValue vp);
 /************************************************************************/
 /*
  * The default locale for the ECMAScript Internationalization API
  * (Intl.Collator, Intl.NumberFormat, Intl.DateTimeFormat).
  * Note that the Internationalization API encourages clients to
  * specify their own locales.
  * The locale string remains owned by the caller.
  */
 extern JS_PUBLIC_API(bool)
 JS_SetDefaultLocale(JSRuntime *rt, const char *locale);
 /*
  * Returns the default locale for the ECMAScript Internationalization API
  * (Intl.Collator, Intl.NumberFormat, Intl.DateTimeFormat).
  * Note that the Internationalization API encourages clients to
  * specify their own locales.
  */
 extern JS_PUBLIC_API(const char*)
 JS_GetDefaultLocale(JSRuntime *rt);
 /*
  * Reset the default locale to OS defaults.
  */
 extern JS_PUBLIC_API(void)
 JS_ResetDefaultLocale(JSRuntime *rt);
 /*
  * Locale specific string conversion and error message callbacks.
  */
 struct JSLocaleCallbacks {
     JSLocaleToUpperCase     localeToUpperCase;
     JSLocaleToLowerCase     localeToLowerCase;
     JSLocaleCompare         localeCompare; // not used #if EXPOSE_INTL_API
     JSLocaleToUnicode       localeToUnicode;
     JSErrorCallback         localeGetErrorMessage;
 };
 /*
  * Establish locale callbacks. The pointer must persist as long as the
  * JSRuntime.  Passing nullptr restores the default behaviour.
  */
 extern JS_PUBLIC_API(void)
 JS_SetLocaleCallbacks(JSRuntime *rt, JSLocaleCallbacks *callbacks);
 /*
  * Return the address of the current locale callbacks struct, which may
  * be nullptr.
  */
 extern JS_PUBLIC_API(JSLocaleCallbacks *)
 JS_GetLocaleCallbacks(JSRuntime *rt);
 /************************************************************************/
 /*
  * Error reporting.
  */
 /*
  * Report an exception represented by the sprintf-like conversion of format
  * and its arguments.  This exception message string is passed to a pre-set
  * JSErrorReporter function (set by JS_SetErrorReporter).
  */
 extern JS_PUBLIC_API(void)
 JS_ReportError(JSContext *cx, const char *format, ...);
 /*
  * Use an errorNumber to retrieve the format string, args are char *
  */
 extern JS_PUBLIC_API(void)
 JS_ReportErrorNumber(JSContext *cx, JSErrorCallback errorCallback,
                      void *userRef, const unsigned errorNumber, ...);
 #ifdef va_start
 extern JS_PUBLIC_API(void)
 JS_ReportErrorNumberVA(JSContext *cx, JSErrorCallback errorCallback,
                        void *userRef, const unsigned errorNumber, va_list ap);
 #endif
 /*
  * Use an errorNumber to retrieve the format string, args are jschar *
  */
 extern JS_PUBLIC_API(void)
 JS_ReportErrorNumberUC(JSContext *cx, JSErrorCallback errorCallback,
                      void *userRef, const unsigned errorNumber, ...);
 extern JS_PUBLIC_API(void)
 JS_ReportErrorNumberUCArray(JSContext *cx, JSErrorCallback errorCallback,
                             void *userRef, const unsigned errorNumber,
                             const jschar **args);
 /*
  * As above, but report a warning instead (JSREPORT_IS_WARNING(report.flags)).
  * Return true if there was no error trying to issue the warning, and if the
  * warning was not converted into an error due to the JSOPTION_WERROR option
  * being set, false otherwise.
  */
 extern JS_PUBLIC_API(bool)
 JS_ReportWarning(JSContext *cx, const char *format, ...);
 extern JS_PUBLIC_API(bool)
 JS_ReportErrorFlagsAndNumber(JSContext *cx, unsigned flags,
                              JSErrorCallback errorCallback, void *userRef,
                              const unsigned errorNumber, ...);
 extern JS_PUBLIC_API(bool)
 JS_ReportErrorFlagsAndNumberUC(JSContext *cx, unsigned flags,
                                JSErrorCallback errorCallback, void *userRef,
                                const unsigned errorNumber, ...);
 /*
  * Complain when out of memory.
  */
 extern JS_PUBLIC_API(void)
 JS_ReportOutOfMemory(JSContext *cx);
 /*
  * Complain when an allocation size overflows the maximum supported limit.
  */
 extern JS_PUBLIC_API(void)
 JS_ReportAllocationOverflow(JSContext *cx);
 struct JSErrorReport {
     const char      *filename;      /* source file name, URL, etc., or null */
     JSPrincipals    *originPrincipals; /* see 'originPrincipals' comment above */
     unsigned        lineno;         /* source line number */
     const char      *linebuf;       /* offending source line without final \n */
     const char      *tokenptr;      /* pointer to error token in linebuf */
     const jschar    *uclinebuf;     /* unicode (original) line buffer */
     const jschar    *uctokenptr;    /* unicode (original) token pointer */
     unsigned        flags;          /* error/warning, etc. */
     unsigned        errorNumber;    /* the error number, e.g. see js.msg */
     const jschar    *ucmessage;     /* the (default) error message */
     const jschar    **messageArgs;  /* arguments for the error message */
     int16_t         exnType;        /* One of the JSExnType constants */
     unsigned        column;         /* zero-based column index in line */
 };
 /*
  * JSErrorReport flag values.  These may be freely composed.
  */
 #define JSREPORT_ERROR      0x0     /* pseudo-flag for default case */
 #define JSREPORT_WARNING    0x1     /* reported via JS_ReportWarning */
 #define JSREPORT_EXCEPTION  0x2     /* exception was thrown */
 #define JSREPORT_STRICT     0x4     /* error or warning due to strict option */
 /*
  * This condition is an error in strict mode code, a warning if
  * JS_HAS_STRICT_OPTION(cx), and otherwise should not be reported at
  * all.  We check the strictness of the context's top frame's script;
  * where that isn't appropriate, the caller should do the right checks
  * itself instead of using this flag.
  */
 #define JSREPORT_STRICT_MODE_ERROR 0x8
 /*
  * If JSREPORT_EXCEPTION is set, then a JavaScript-catchable exception
  * has been thrown for this runtime error, and the host should ignore it.
  * Exception-aware hosts should also check for JS_IsExceptionPending if
  * JS_ExecuteScript returns failure, and signal or propagate the exception, as
  * appropriate.
  */
 #define JSREPORT_IS_WARNING(flags)      (((flags) & JSREPORT_WARNING) != 0)
 #define JSREPORT_IS_EXCEPTION(flags)    (((flags) & JSREPORT_EXCEPTION) != 0)
 #define JSREPORT_IS_STRICT(flags)       (((flags) & JSREPORT_STRICT) != 0)
 #define JSREPORT_IS_STRICT_MODE_ERROR(flags) (((flags) &                      \
                                               JSREPORT_STRICT_MODE_ERROR) != 0)
 extern JS_PUBLIC_API(JSErrorReporter)
 JS_GetErrorReporter(JSContext *cx);
 extern JS_PUBLIC_API(JSErrorReporter)
 JS_SetErrorReporter(JSContext *cx, JSErrorReporter er);
 namespace JS {
 extern JS_PUBLIC_API(bool)
 CreateTypeError(JSContext *cx, HandleString stack, HandleString fileName,
                 uint32_t lineNumber, uint32_t columnNumber, JSErrorReport *report,
                 HandleString message, MutableHandleValue rval);
 /************************************************************************/
 /*
  * Weak Maps.
  */
 extern JS_PUBLIC_API(JSObject *)
 NewWeakMapObject(JSContext *cx);
 extern JS_PUBLIC_API(bool)
 IsWeakMapObject(JSObject *obj);
 extern JS_PUBLIC_API(bool)
 GetWeakMapEntry(JSContext *cx, JS::HandleObject mapObj, JS::HandleObject key,
                 JS::MutableHandleValue val);
 extern JS_PUBLIC_API(bool)
 SetWeakMapEntry(JSContext *cx, JS::HandleObject mapObj, JS::HandleObject key,
                 JS::HandleValue val);
 } /* namespace JS */
 /*
  * Dates.
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewDateObject(JSContext *cx, int year, int mon, int mday, int hour, int min, int sec);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewDateObjectMsec(JSContext *cx, double msec);
 /*
  * Infallible predicate to test whether obj is a date object.
  */
 extern JS_PUBLIC_API(bool)
 JS_ObjectIsDate(JSContext *cx, JS::HandleObject obj);
 /*
  * Clears the cache of calculated local time from each Date object.
  * Call to propagate a system timezone change.
  */
 extern JS_PUBLIC_API(void)
 JS_ClearDateCaches(JSContext *cx);
 /************************************************************************/
 /*
  * Regular Expressions.
  */
 #define JSREG_FOLD      0x01    /* fold uppercase to lowercase */
 #define JSREG_GLOB      0x02    /* global exec, creates array of matches */
 #define JSREG_MULTILINE 0x04    /* treat ^ and $ as begin and end of line */
 #define JSREG_STICKY    0x08    /* only match starting at lastIndex */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewRegExpObject(JSContext *cx, JS::HandleObject obj, char *bytes, size_t length,
                    unsigned flags);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewUCRegExpObject(JSContext *cx, JS::HandleObject obj, jschar *chars, size_t length,
                      unsigned flags);
 extern JS_PUBLIC_API(void)
 JS_SetRegExpInput(JSContext *cx, JS::HandleObject obj, JS::HandleString input,
                   bool multiline);
 extern JS_PUBLIC_API(void)
 JS_ClearRegExpStatics(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(bool)
 JS_ExecuteRegExp(JSContext *cx, JS::HandleObject obj, JS::HandleObject reobj,
                  jschar *chars, size_t length, size_t *indexp, bool test,
                  JS::MutableHandleValue rval);
 /* RegExp interface for clients without a global object. */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewRegExpObjectNoStatics(JSContext *cx, char *bytes, size_t length, unsigned flags);
 extern JS_PUBLIC_API(JSObject *)
 JS_NewUCRegExpObjectNoStatics(JSContext *cx, jschar *chars, size_t length, unsigned flags);
 extern JS_PUBLIC_API(bool)
 JS_ExecuteRegExpNoStatics(JSContext *cx, JS::HandleObject reobj, jschar *chars, size_t length,
                           size_t *indexp, bool test, JS::MutableHandleValue rval);
 extern JS_PUBLIC_API(bool)
 JS_ObjectIsRegExp(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(unsigned)
 JS_GetRegExpFlags(JSContext *cx, JS::HandleObject obj);
 extern JS_PUBLIC_API(JSString *)
 JS_GetRegExpSource(JSContext *cx, JS::HandleObject obj);
 /************************************************************************/
 extern JS_PUBLIC_API(bool)
 JS_IsExceptionPending(JSContext *cx);
 extern JS_PUBLIC_API(bool)
 JS_GetPendingException(JSContext *cx, JS::MutableHandleValue vp);
 extern JS_PUBLIC_API(void)
 JS_SetPendingException(JSContext *cx, JS::HandleValue v);
 extern JS_PUBLIC_API(void)
 JS_ClearPendingException(JSContext *cx);
 extern JS_PUBLIC_API(bool)
 JS_ReportPendingException(JSContext *cx);
 namespace JS {
 /*
  * Save and later restore the current exception state of a given JSContext.
  * This is useful for implementing behavior in C++ that's like try/catch
  * or try/finally in JS.
  *
  * Typical usage:
  *
  *     bool ok = JS_EvaluateScript(cx, ...);
  *     AutoSaveExceptionState savedExc(cx);
  *     ... cleanup that might re-enter JS ...
  *     return ok;
  */
 class JS_PUBLIC_API(AutoSaveExceptionState)
 {
   private:
     JSContext *context;
     bool wasThrowing;
     RootedValue exceptionValue;
   public:
     /*
      * Take a snapshot of cx's current exception state. Then clear any current
      * pending exception in cx.
      */
     explicit AutoSaveExceptionState(JSContext *cx);
     /*
      * If neither drop() nor restore() was called, restore the exception
      * state only if no exception is currently pending on cx.
      */
     ~AutoSaveExceptionState();
     /*
      * Discard any stored exception state.
      * If this is called, the destructor is a no-op.
      */
     void drop() {
         wasThrowing = false;
         exceptionValue.setUndefined();
     }
     /*
      * Replace cx's exception state with the stored exception state. Then
      * discard the stored exception state. If this is called, the
      * destructor is a no-op.
      */
     void restore();
 };
 } /* namespace JS */
 /* Deprecated API. Use AutoSaveExceptionState instead. */
 extern JS_PUBLIC_API(JSExceptionState *)
 JS_SaveExceptionState(JSContext *cx);
 extern JS_PUBLIC_API(void)
 JS_RestoreExceptionState(JSContext *cx, JSExceptionState *state);
 extern JS_PUBLIC_API(void)
 JS_DropExceptionState(JSContext *cx, JSExceptionState *state);
 /*
  * If the given object is an exception object, the exception will have (or be
  * able to lazily create) an error report struct, and this function will return
  * the address of that struct.  Otherwise, it returns nullptr. The lifetime
  * of the error report struct that might be returned is the same as the
  * lifetime of the exception object.
  */
 extern JS_PUBLIC_API(JSErrorReport *)
 JS_ErrorFromException(JSContext *cx, JS::HandleObject obj);
 /*
  * Throws a StopIteration exception on cx.
  */
 extern JS_PUBLIC_API(bool)
 JS_ThrowStopIteration(JSContext *cx);
 extern JS_PUBLIC_API(bool)
 JS_IsStopIteration(jsval v);
 extern JS_PUBLIC_API(intptr_t)
 JS_GetCurrentThread();
 /*
  * A JS runtime always has an "owner thread". The owner thread is set when the
  * runtime is created (to the current thread) and practically all entry points
  * into the JS engine check that a runtime (or anything contained in the
  * runtime: context, compartment, object, etc) is only touched by its owner
  * thread. Embeddings may check this invariant outside the JS engine by calling
  * JS_AbortIfWrongThread (which will abort if not on the owner thread, even for
  * non-debug builds).
  */
 extern JS_PUBLIC_API(void)
 JS_AbortIfWrongThread(JSRuntime *rt);
 /************************************************************************/
 /*
  * A constructor can request that the JS engine create a default new 'this'
  * object of the given class, using the callee to determine parentage and
  * [[Prototype]].
  */
 extern JS_PUBLIC_API(JSObject *)
 JS_NewObjectForConstructor(JSContext *cx, const JSClass *clasp, const JS::CallArgs& args);
 /************************************************************************/
 #ifdef JS_GC_ZEAL
 #define JS_DEFAULT_ZEAL_FREQ 100
 extern JS_PUBLIC_API(void)
 JS_SetGCZeal(JSContext *cx, uint8_t zeal, uint32_t frequency);
 extern JS_PUBLIC_API(void)
 JS_ScheduleGC(JSContext *cx, uint32_t count);
 #endif
 extern JS_PUBLIC_API(void)
 JS_SetParallelParsingEnabled(JSRuntime *rt, bool enabled);
 extern JS_PUBLIC_API(void)
 JS_SetParallelIonCompilationEnabled(JSRuntime *rt, bool enabled);
 #define JIT_COMPILER_OPTIONS(Register)                                  \
     Register(BASELINE_USECOUNT_TRIGGER, "baseline.usecount.trigger")    \
     Register(ION_USECOUNT_TRIGGER, "ion.usecount.trigger")              \
     Register(ION_ENABLE, "ion.enable")                                  \
     Register(BASELINE_ENABLE, "baseline.enable")                        \
     Register(PARALLEL_COMPILATION_ENABLE, "parallel-compilation.enable")
 typedef enum JSJitCompilerOption {
 #define JIT_COMPILER_DECLARE(key, str) \
     JSJITCOMPILER_ ## key,
     JIT_COMPILER_OPTIONS(JIT_COMPILER_DECLARE)
 #undef JIT_COMPILER_DECLARE
     JSJITCOMPILER_NOT_AN_OPTION
 } JSJitCompilerOption;
 extern JS_PUBLIC_API(void)
 JS_SetGlobalJitCompilerOption(JSRuntime *rt, JSJitCompilerOption opt, uint32_t value);
 extern JS_PUBLIC_API(int)
 JS_GetGlobalJitCompilerOption(JSRuntime *rt, JSJitCompilerOption opt);
 /*
  * Convert a uint32_t index into a jsid.
  */
 extern JS_PUBLIC_API(bool)
 JS_IndexToId(JSContext *cx, uint32_t index, JS::MutableHandleId);
 /*
  * Convert chars into a jsid.
  *
  * |chars| may not be an index.
  */
 extern JS_PUBLIC_API(bool)
 JS_CharsToId(JSContext* cx, JS::TwoByteChars chars, JS::MutableHandleId);
 /*
  *  Test if the given string is a valid ECMAScript identifier
  */
 extern JS_PUBLIC_API(bool)
 JS_IsIdentifier(JSContext *cx, JS::HandleString str, bool *isIdentifier);
 namespace JS {
 /*
  * AutoFilename encapsulates a pointer to a C-string and keeps the C-string
  * alive for as long as the associated AutoFilename object is alive.
  */
 class MOZ_STACK_CLASS JS_PUBLIC_API(AutoFilename)
 {
     void *scriptSource_;
     AutoFilename(const AutoFilename &) MOZ_DELETE;
     void operator=(const AutoFilename &) MOZ_DELETE;
   public:
     AutoFilename() : scriptSource_(nullptr) {}
     ~AutoFilename() { reset(nullptr); }
     const char *get() const;
     void reset(void *newScriptSource);
 };
 /*
  * Return the current filename and line number of the most currently running
  * frame. Returns true if a scripted frame was found, false otherwise.
  *
  * If a the embedding has hidden the scripted caller for the topmost activation
  * record, this will also return false.
  */
 extern JS_PUBLIC_API(bool)
 DescribeScriptedCaller(JSContext *cx, AutoFilename *filename = nullptr,
                        unsigned *lineno = nullptr);
 extern JS_PUBLIC_API(JSObject *)
 GetScriptedCallerGlobal(JSContext *cx);
 /*
  * Informs the JS engine that the scripted caller should be hidden. This can be
  * used by the embedding to maintain an override of the scripted caller in its
  * calculations, by hiding the scripted caller in the JS engine and pushing data
  * onto a separate stack, which it inspects when DescribeScriptedCaller returns
  * null.
  *
  * We maintain a counter on each activation record. Add() increments the counter
  * of the topmost activation, and Remove() decrements it. The count may never
  * drop below zero, and must always be exactly zero when the activation is
  * popped from the stack.
  */
 extern JS_PUBLIC_API(void)
 HideScriptedCaller(JSContext *cx);
 extern JS_PUBLIC_API(void)
 UnhideScriptedCaller(JSContext *cx);
 class AutoHideScriptedCaller
 {
   public:
     AutoHideScriptedCaller(JSContext *cx
                            MOZ_GUARD_OBJECT_NOTIFIER_PARAM)
       : mContext(cx)
     {
         MOZ_GUARD_OBJECT_NOTIFIER_INIT;
         HideScriptedCaller(mContext);
     }
     ~AutoHideScriptedCaller() {
         UnhideScriptedCaller(mContext);
     }
   protected:
     JSContext *mContext;
     MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
 };
 } /* namespace JS */
 /*
  * Encode/Decode interpreted scripts and functions to/from memory.
  */
 extern JS_PUBLIC_API(void *)
 JS_EncodeScript(JSContext *cx, JS::HandleScript script, uint32_t *lengthp);
 extern JS_PUBLIC_API(void *)
 JS_EncodeInterpretedFunction(JSContext *cx, JS::HandleObject funobj, uint32_t *lengthp);
 extern JS_PUBLIC_API(JSScript *)
 JS_DecodeScript(JSContext *cx, const void *data, uint32_t length, JSPrincipals *originPrincipals);
 extern JS_PUBLIC_API(JSObject *)
 JS_DecodeInterpretedFunction(JSContext *cx, const void *data, uint32_t length,
                              JSPrincipals *originPrincipals);
 namespace JS {
 /*
  * This callback represents a request by the JS engine to open for reading the
  * existing cache entry for the given global and char range that may contain a
  * module. If a cache entry exists, the callback shall return 'true' and return
  * the size, base address and an opaque file handle as outparams. If the
  * callback returns 'true', the JS engine guarantees a call to
  * CloseAsmJSCacheEntryForReadOp, passing the same base address, size and
  * handle.
  */
 typedef bool
 (* OpenAsmJSCacheEntryForReadOp)(HandleObject global, const jschar *begin, const jschar *limit,
                                  size_t *size, const uint8_t **memory, intptr_t *handle);
 typedef void
 (* CloseAsmJSCacheEntryForReadOp)(HandleObject global, size_t size, const uint8_t *memory,
                                   intptr_t handle);
 /*
  * This callback represents a request by the JS engine to open for writing a
  * cache entry of the given size for the given global and char range containing
  * the just-compiled module. If cache entry space is available, the callback
  * shall return 'true' and return the base address and an opaque file handle as
  * outparams. If the callback returns 'true', the JS engine guarantees a call
  * to CloseAsmJSCacheEntryForWriteOp passing the same base address, size and
  * handle.
  *
  * If 'installed' is true, then the cache entry is associated with a permanently
  * installed JS file (e.g., in a packaged webapp). This information allows the
  * embedding to store the cache entry in a installed location associated with
  * the principal of 'global' where it will not be evicted until the associated
  * installed JS file is removed.
  */
 typedef bool
 (* OpenAsmJSCacheEntryForWriteOp)(HandleObject global, bool installed,
                                   const jschar *begin, const jschar *end,
                                   size_t size, uint8_t **memory, intptr_t *handle);
 typedef void
 (* CloseAsmJSCacheEntryForWriteOp)(HandleObject global, size_t size, uint8_t *memory,
                                    intptr_t handle);
 typedef js::Vector<char, 0, js::SystemAllocPolicy> BuildIdCharVector;
 // Return the buildId (represented as a sequence of characters) associated with
 // the currently-executing build. If the JS engine is embedded such that a
 // single cache entry can be observed by different compiled versions of the JS
 // engine, it is critical that the buildId shall change for each new build of
 // the JS engine.
 typedef bool
 (* BuildIdOp)(BuildIdCharVector *buildId);
 struct AsmJSCacheOps
 {
     OpenAsmJSCacheEntryForReadOp openEntryForRead;
     CloseAsmJSCacheEntryForReadOp closeEntryForRead;
     OpenAsmJSCacheEntryForWriteOp openEntryForWrite;
     CloseAsmJSCacheEntryForWriteOp closeEntryForWrite;
     BuildIdOp buildId;
 };
 extern JS_PUBLIC_API(void)
 SetAsmJSCacheOps(JSRuntime *rt, const AsmJSCacheOps *callbacks);
 /*
  * Convenience class for imitating a JS level for-of loop. Typical usage:
  *
  *     ForOfIterator it(cx);
  *     if (!it.init(iterable))
  *       return false;
  *     RootedValue val(cx);
  *     while (true) {
  *       bool done;
  *       if (!it.next(&val, &done))
  *         return false;
  *       if (done)
  *         break;
  *       if (!DoStuff(cx, val))
  *         return false;
  *     }
  */
 class MOZ_STACK_CLASS JS_PUBLIC_API(ForOfIterator) {
   protected:
     JSContext *cx_;
     /*
      * Use the ForOfPIC on the global object (see vm/GlobalObject.h) to try
      * to optimize iteration across arrays.
      *
      *  Case 1: Regular Iteration
      *      iterator - pointer to the iterator object.
      *      index - fixed to NOT_ARRAY (== UINT32_MAX)
      *
      *  Case 2: Optimized Array Iteration
      *      iterator - pointer to the array object.
      *      index - current position in array.
      *
      * The cases are distinguished by whether or not |index| is equal to NOT_ARRAY.
      */
     JS::RootedObject iterator;
     uint32_t index;
     static const uint32_t NOT_ARRAY = UINT32_MAX;
     ForOfIterator(const ForOfIterator &) MOZ_DELETE;
     ForOfIterator &operator=(const ForOfIterator &) MOZ_DELETE;
   public:
     ForOfIterator(JSContext *cx) : cx_(cx), iterator(cx_), index(NOT_ARRAY) { }
     enum NonIterableBehavior {
         ThrowOnNonIterable,
         AllowNonIterable
     };
     /*
      * Initialize the iterator.  If AllowNonIterable is passed then if iterable
      * does not have a callable @@iterator init() will just return true instead
      * of throwing.  Callers should then check valueIsIterable() before
      * continuing with the iteration.
      */
     bool init(JS::HandleValue iterable,
               NonIterableBehavior nonIterableBehavior = ThrowOnNonIterable);
     /*
      * Get the next value from the iterator.  If false *done is true
      * after this call, do not examine val.
      */
     bool next(JS::MutableHandleValue val, bool *done);
     /*
      * If initialized with throwOnNonCallable = false, check whether
      * the value is iterable.
      */
     bool valueIsIterable() const {
         return iterator;
     }
   private:
     inline bool nextFromOptimizedArray(MutableHandleValue val, bool *done);
     bool materializeArrayIterator();
 };
 /*
  * If a large allocation fails, the JS engine may call the large-allocation-
  * failure callback, if set, to allow the embedding to flush caches, possibly
  * perform shrinking GCs, etc. to make some room so that the allocation will
  * succeed if retried. After the callback returns, the JS engine will try to
  * allocate again and may be succesful.
  */
 typedef void
 (* LargeAllocationFailureCallback)();
 extern JS_PUBLIC_API(void)
 SetLargeAllocationFailureCallback(JSRuntime *rt, LargeAllocationFailureCallback afc);
 /*
  * Unlike the error reporter, which is only called if the exception for an OOM
  * bubbles up and is not caught, the OutOfMemoryCallback is called immediately
  * at the OOM site to allow the embedding to capture the current state of heap
  * allocation before anything is freed. If the large-allocation-failure callback
  * is called at all (not all allocation sites call the large-allocation-failure
  * callback on failure), it is called before the out-of-memory callback; the
  * out-of-memory callback is only called if the allocation still fails after the
  * large-allocation-failure callback has returned.
  */
 typedef void
 (* OutOfMemoryCallback)(JSContext *cx);
 extern JS_PUBLIC_API(void)
 SetOutOfMemoryCallback(JSRuntime *rt, OutOfMemoryCallback cb);
 } /* namespace JS */
 #endif /* jsapi_h */

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js/src/jsapi.h