/*
* Copyright (C) 2013 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
#import "config.h"
#import "JSManagedValue.h"
#if JSC_OBJC_API_ENABLED
#import "APICast.h"
#import "Heap.h"
#import "JSContextInternal.h"
#import "JSValueInternal.h"
#import "Weak.h"
#import "WeakHandleOwner.h"
#import "ObjcRuntimeExtras.h"
#import "JSCInlines.h"
class JSManagedValueHandleOwner : public JSC::WeakHandleOwner {
public:
virtual void finalize(JSC::Handle<JSC::Unknown>, void* context) override;
virtual bool isReachableFromOpaqueRoots(JSC::Handle<JSC::Unknown>, void* context, JSC::SlotVisitor&) override;
};
static JSManagedValueHandleOwner* managedValueHandleOwner()
{
DEPRECATED_DEFINE_STATIC_LOCAL(JSManagedValueHandleOwner, jsManagedValueHandleOwner, ());
return &jsManagedValueHandleOwner;
}
class WeakValueRef {
public:
WeakValueRef()
: m_tag(NotSet)
{
}
~WeakValueRef()
{
clear();
}
void clear()
{
switch (m_tag) {
case NotSet:
return;
case Primitive:
u.m_primitive = JSC::JSValue();
return;
case Object:
u.m_object.clear();
return;
case String:
u.m_string.clear();
return;
}
RELEASE_ASSERT_NOT_REACHED();
}
bool isClear() const
{
switch (m_tag) {
case NotSet:
return true;
case Primitive:
return !u.m_primitive;
case Object:
return !u.m_object;
case String:
return !u.m_string;
}
RELEASE_ASSERT_NOT_REACHED();
}
bool isSet() const { return m_tag != NotSet; }
bool isPrimitive() const { return m_tag == Primitive; }
bool isObject() const { return m_tag == Object; }
bool isString() const { return m_tag == String; }
void setPrimitive(JSC::JSValue primitive)
{
ASSERT(!isSet());
ASSERT(!u.m_primitive);
ASSERT(primitive.isPrimitive());
m_tag = Primitive;
u.m_primitive = primitive;
}
void setObject(JSC::JSObject* object, void* context)
{
ASSERT(!isSet());
ASSERT(!u.m_object);
m_tag = Object;
JSC::Weak<JSC::JSObject> weak(object, managedValueHandleOwner(), context);
u.m_object.swap(weak);
}
void setString(JSC::JSString* string, void* context)
{
ASSERT(!isSet());
ASSERT(!u.m_object);
m_tag = String;
JSC::Weak<JSC::JSString> weak(string, managedValueHandleOwner(), context);
u.m_string.swap(weak);
}
JSC::JSObject* object()
{
ASSERT(isObject());
return u.m_object.get();
}
JSC::JSValue primitive()
{
ASSERT(isPrimitive());
return u.m_primitive;
}
JSC::JSString* string()
{
ASSERT(isString());
return u.m_string.get();
}
private:
enum WeakTypeTag { NotSet, Primitive, Object, String };
WeakTypeTag m_tag;
union WeakValueUnion {
public:
WeakValueUnion ()
: m_primitive(JSC::JSValue())
{
}
~WeakValueUnion()
{
ASSERT(!m_primitive);
}
JSC::JSValue m_primitive;
JSC::Weak<JSC::JSObject> m_object;
JSC::Weak<JSC::JSString> m_string;
} u;
};
@implementation JSManagedValue {
JSC::Weak<JSC::JSGlobalObject> m_globalObject;
RefPtr<JSC::JSLock> m_lock;
WeakValueRef m_weakValue;
NSMapTable *m_owners;
}
+ (JSManagedValue *)managedValueWithValue:(JSValue *)value
{
return [[[self alloc] initWithValue:value] autorelease];
}
+ (JSManagedValue *)managedValueWithValue:(JSValue *)value andOwner:(id)owner
{
JSManagedValue *managedValue = [[self alloc] initWithValue:value];
[value.context.virtualMachine addManagedReference:managedValue withOwner:owner];
return [managedValue autorelease];
}
- (instancetype)init
{
return [self initWithValue:nil];
}
- (instancetype)initWithValue:(JSValue *)value
{
self = [super init];
if (!self)
return nil;
if (!value)
return self;
JSC::ExecState* exec = toJS([value.context JSGlobalContextRef]);
JSC::JSGlobalObject* globalObject = exec->lexicalGlobalObject();
JSC::Weak<JSC::JSGlobalObject> weak(globalObject, managedValueHandleOwner(), self);
m_globalObject.swap(weak);
m_lock = &exec->vm().apiLock();
NSPointerFunctionsOptions weakIDOptions = NSPointerFunctionsWeakMemory | NSPointerFunctionsObjectPersonality;
NSPointerFunctionsOptions integerOptions = NSPointerFunctionsOpaqueMemory | NSPointerFunctionsIntegerPersonality;
m_owners = [[NSMapTable alloc] initWithKeyOptions:weakIDOptions valueOptions:integerOptions capacity:1];
JSC::JSValue jsValue = toJS(exec, [value JSValueRef]);
if (jsValue.isObject())
m_weakValue.setObject(JSC::jsCast<JSC::JSObject*>(jsValue.asCell()), self);
else if (jsValue.isString())
m_weakValue.setString(JSC::jsCast<JSC::JSString*>(jsValue.asCell()), self);
else
m_weakValue.setPrimitive(jsValue);
return self;
}
- (void)dealloc
{
JSVirtualMachine *virtualMachine = [[[self value] context] virtualMachine];
if (virtualMachine) {
NSMapTable *copy = [m_owners copy];
for (id owner in [copy keyEnumerator]) {
size_t count = reinterpret_cast<size_t>(NSMapGet(m_owners, owner));
while (count--)
[virtualMachine removeManagedReference:self withOwner:owner];
}
[copy release];
}
[self disconnectValue];
[m_owners release];
[super dealloc];
}
- (void)didAddOwner:(id)owner
{
size_t count = reinterpret_cast<size_t>(NSMapGet(m_owners, owner));
NSMapInsert(m_owners, owner, reinterpret_cast<void*>(count + 1));
}
- (void)didRemoveOwner:(id)owner
{
size_t count = reinterpret_cast<size_t>(NSMapGet(m_owners, owner));
if (!count)
return;
if (count == 1) {
NSMapRemove(m_owners, owner);
return;
}
NSMapInsert(m_owners, owner, reinterpret_cast<void*>(count - 1));
}
- (JSValue *)value
{
WTF::Locker<JSC::JSLock> locker(m_lock.get());
if (!m_lock->vm())
return nil;
JSC::JSLockHolder apiLocker(m_lock->vm());
if (!m_globalObject)
return nil;
if (m_weakValue.isClear())
return nil;
JSC::ExecState* exec = m_globalObject->globalExec();
JSContext *context = [JSContext contextWithJSGlobalContextRef:toGlobalRef(exec)];
JSC::JSValue value;
if (m_weakValue.isPrimitive())
value = m_weakValue.primitive();
else if (m_weakValue.isString())
value = m_weakValue.string();
else
value = m_weakValue.object();
return [JSValue valueWithJSValueRef:toRef(exec, value) inContext:context];
}
- (void)disconnectValue
{
m_globalObject.clear();
m_weakValue.clear();
}
@end
@interface JSManagedValue (PrivateMethods)
- (void)disconnectValue;
@end
bool JSManagedValueHandleOwner::isReachableFromOpaqueRoots(JSC::Handle<JSC::Unknown>, void* context, JSC::SlotVisitor& visitor)
{
JSManagedValue *managedValue = static_cast<JSManagedValue *>(context);
return visitor.containsOpaqueRoot(managedValue);
}
void JSManagedValueHandleOwner::finalize(JSC::Handle<JSC::Unknown>, void* context)
{
JSManagedValue *managedValue = static_cast<JSManagedValue *>(context);
[managedValue disconnectValue];
}
#endif // JSC_OBJC_API_ENABLED