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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef jsiter_h
#define jsiter_h
/*
* JavaScript iterators.
*/
#include "mozilla/MemoryReporting.h"
#include "jscntxt.h"
#include "gc/Barrier.h"
#include "vm/ReceiverGuard.h"
#include "vm/Stack.h"
/*
* For cacheable native iterators, whether the iterator is currently active.
* Not serialized by XDR.
*/
#define JSITER_ACTIVE 0x1000
#define JSITER_UNREUSABLE 0x2000
namespace js {
class PropertyIteratorObject;
struct NativeIterator
{
GCPtrObject obj; // Object being iterated.
JSObject* iterObj_; // Internal iterator object.
GCPtrFlatString* props_array;
GCPtrFlatString* props_cursor;
GCPtrFlatString* props_end;
HeapReceiverGuard* guard_array;
uint32_t guard_length;
uint32_t guard_key;
uint32_t flags;
private:
/* While in compartment->enumerators, these form a doubly linked list. */
NativeIterator* next_;
NativeIterator* prev_;
public:
bool isKeyIter() const {
return (flags & JSITER_FOREACH) == 0;
}
inline GCPtrFlatString* begin() const {
return props_array;
}
inline GCPtrFlatString* end() const {
return props_end;
}
size_t numKeys() const {
return end() - begin();
}
JSObject* iterObj() const {
return iterObj_;
}
GCPtrFlatString* current() const {
MOZ_ASSERT(props_cursor < props_end);
return props_cursor;
}
NativeIterator* next() {
return next_;
}
static inline size_t offsetOfNext() {
return offsetof(NativeIterator, next_);
}
static inline size_t offsetOfPrev() {
return offsetof(NativeIterator, prev_);
}
void incCursor() {
props_cursor = props_cursor + 1;
}
void link(NativeIterator* other) {
/* A NativeIterator cannot appear in the enumerator list twice. */
MOZ_ASSERT(!next_ && !prev_);
MOZ_ASSERT(flags & JSITER_ENUMERATE);
this->next_ = other;
this->prev_ = other->prev_;
other->prev_->next_ = this;
other->prev_ = this;
}
void unlink() {
MOZ_ASSERT(flags & JSITER_ENUMERATE);
next_->prev_ = prev_;
prev_->next_ = next_;
next_ = nullptr;
prev_ = nullptr;
}
static NativeIterator* allocateSentinel(JSContext* maybecx);
static NativeIterator* allocateIterator(JSContext* cx, uint32_t slength, uint32_t plength);
void init(JSObject* obj, JSObject* iterObj, unsigned flags, uint32_t slength, uint32_t key);
bool initProperties(JSContext* cx, Handle<PropertyIteratorObject*> obj,
const js::AutoIdVector& props);
void trace(JSTracer* trc);
static void destroy(NativeIterator* iter) {
js_free(iter);
}
};
class PropertyIteratorObject : public NativeObject
{
static const ClassOps classOps_;
public:
static const Class class_;
NativeIterator* getNativeIterator() const {
return static_cast<js::NativeIterator*>(getPrivate());
}
void setNativeIterator(js::NativeIterator* ni) {
setPrivate(ni);
}
size_t sizeOfMisc(mozilla::MallocSizeOf mallocSizeOf) const;
private:
static void trace(JSTracer* trc, JSObject* obj);
static void finalize(FreeOp* fop, JSObject* obj);
};
class ArrayIteratorObject : public JSObject
{
public:
static const Class class_;
};
class StringIteratorObject : public JSObject
{
public:
static const Class class_;
};
class RegExpStringIteratorObject : public JSObject
{
public:
static const Class class_;
};
bool
GetIterator(JSContext* cx, HandleObject obj, unsigned flags, MutableHandleObject objp);
JSObject*
GetIteratorObject(JSContext* cx, HandleObject obj, unsigned flags);
/*
* Creates either a key or value iterator, depending on flags. For a value
* iterator, performs value-lookup to convert the given list of jsids.
*/
bool
EnumeratedIdVectorToIterator(JSContext* cx, HandleObject obj, unsigned flags, AutoIdVector& props,
MutableHandleObject objp);
bool
NewEmptyPropertyIterator(JSContext* cx, unsigned flags, MutableHandleObject objp);
/*
* Convert the value stored in *vp to its iteration object. The flags should
* contain JSITER_ENUMERATE if js::ValueToIterator is called when enumerating
* for-in semantics are required, and when the caller can guarantee that the
* iterator will never be exposed to scripts.
*/
JSObject*
ValueToIterator(JSContext* cx, unsigned flags, HandleValue vp);
bool
CloseIterator(JSContext* cx, HandleObject iterObj);
bool
UnwindIteratorForException(JSContext* cx, HandleObject obj);
bool
IteratorCloseForException(JSContext* cx, HandleObject obj);
void
UnwindIteratorForUncatchableException(JSContext* cx, JSObject* obj);
bool
IteratorConstructor(JSContext* cx, unsigned argc, Value* vp);
extern bool
SuppressDeletedProperty(JSContext* cx, HandleObject obj, jsid id);
extern bool
SuppressDeletedElement(JSContext* cx, HandleObject obj, uint32_t index);
/*
* IteratorMore() returns the next iteration value. If no value is available,
* MagicValue(JS_NO_ITER_VALUE) is returned.
*/
extern bool
IteratorMore(JSContext* cx, HandleObject iterobj, MutableHandleValue rval);
extern bool
ThrowStopIteration(JSContext* cx);
/*
* Create an object of the form { value: VALUE, done: DONE }.
* ES 2017 draft 7.4.7.
*/
extern JSObject*
CreateIterResultObject(JSContext* cx, HandleValue value, bool done);
extern JSObject*
InitLegacyIteratorClass(JSContext* cx, HandleObject obj);
extern JSObject*
InitStopIterationClass(JSContext* cx, HandleObject obj);
enum class IteratorKind { Sync, Async };
} /* namespace js */
#endif /* jsiter_h */
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