1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
|
/*
* Copyright (C) 2018 Igalia S.L.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "JSCWeakValue.h"
#include "APICast.h"
#include "JSCContextPrivate.h"
#include "JSCInlines.h"
#include "JSCValuePrivate.h"
#include "JSWeakValue.h"
#include "WeakHandleOwner.h"
#include <wtf/glib/GRefPtr.h>
#include <wtf/glib/GUniquePtr.h>
#include <wtf/glib/WTFGType.h>
/**
* JSCWeakValue:
* @short_description: JavaScript weak value
* @title: JSCWeakValue
* @see_also: JSCValue
*
* JSCWeakValue represents a weak reference to a value in a #JSCContext. It can be used
* to keep a reference to a JavaScript value without protecting it from being garbage
* collected and without referencing the #JSCContext either.
*/
enum {
PROP_0,
PROP_VALUE,
};
enum {
CLEARED,
LAST_SIGNAL
};
struct _JSCWeakValuePrivate {
JSC::Weak<JSC::JSGlobalObject> globalObject;
RefPtr<JSC::JSLock> lock;
JSC::JSWeakValue weakValueRef;
};
static std::array<unsigned, LAST_SIGNAL> signals;
WEBKIT_DEFINE_FINAL_TYPE(JSCWeakValue, jsc_weak_value, G_TYPE_OBJECT, GObject)
static void jscWeakValueClear(JSCWeakValue* weakValue)
{
JSCWeakValuePrivate* priv = weakValue->priv;
priv->globalObject.clear();
priv->weakValueRef.clear();
}
class JSCWeakValueHandleOwner final : public JSC::WeakHandleOwner {
public:
void finalize(JSC::Handle<JSC::Unknown>, void* context) final
{
auto* weakValue = JSC_WEAK_VALUE(context);
jscWeakValueClear(weakValue);
g_signal_emit(weakValue, signals[CLEARED], 0, nullptr);
}
};
static JSCWeakValueHandleOwner& weakValueHandleOwner()
{
static NeverDestroyed<JSCWeakValueHandleOwner> jscWeakValueHandleOwner;
return jscWeakValueHandleOwner;
}
static void jscWeakValueInitialize(JSCWeakValue* weakValue, JSCValue* value)
{
JSCWeakValuePrivate* priv = weakValue->priv;
auto* jsContext = jscContextGetJSContext(jsc_value_get_context(value));
JSC::JSGlobalObject* globalObject = toJS(jsContext);
JSC::JSLockHolder locker(globalObject->vm());
auto& owner = weakValueHandleOwner();
JSC::Weak<JSC::JSGlobalObject> weak(globalObject, &owner, weakValue);
priv->globalObject.swap(weak);
priv->lock = &globalObject->vm().apiLock();
JSC::JSValue jsValue = toJS(globalObject, jscValueGetJSValue(value));
if (jsValue.isObject())
priv->weakValueRef.setObject(JSC::jsCast<JSC::JSObject*>(jsValue.asCell()), owner, weakValue);
else if (jsValue.isString())
priv->weakValueRef.setString(JSC::jsCast<JSC::JSString*>(jsValue.asCell()), owner, weakValue);
else
priv->weakValueRef.setPrimitive(jsValue);
}
static void jscWeakValueSetProperty(GObject* object, guint propID, const GValue* value, GParamSpec* paramSpec)
{
switch (propID) {
case PROP_VALUE:
jscWeakValueInitialize(JSC_WEAK_VALUE(object), JSC_VALUE(g_value_get_object(value)));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID(object, propID, paramSpec);
}
}
static void jscWeakValueDispose(GObject* object)
{
JSCWeakValue* weakValue = JSC_WEAK_VALUE(object);
jscWeakValueClear(weakValue);
G_OBJECT_CLASS(jsc_weak_value_parent_class)->dispose(object);
}
static void jsc_weak_value_class_init(JSCWeakValueClass* klass)
{
GObjectClass* objClass = G_OBJECT_CLASS(klass);
objClass->set_property = jscWeakValueSetProperty;
objClass->dispose = jscWeakValueDispose;
/**
* JSCWeakValue:value:
*
* The #JSCValue referencing the JavaScript value.
*/
g_object_class_install_property(objClass,
PROP_VALUE,
g_param_spec_object(
"value",
nullptr, nullptr,
JSC_TYPE_VALUE,
static_cast<GParamFlags>(WEBKIT_PARAM_WRITABLE | G_PARAM_CONSTRUCT_ONLY)));
/**
* JSCWeakValue::cleared:
* @weak_value: the #JSCWeakValue
*
* This signal is emitted when the JavaScript value is destroyed.
*/
signals[CLEARED] = g_signal_new(
"cleared",
G_TYPE_FROM_CLASS(klass),
G_SIGNAL_RUN_LAST,
0, nullptr, nullptr,
g_cclosure_marshal_generic,
G_TYPE_NONE, 0,
G_TYPE_NONE);
}
/**
* jsc_weak_value_new:
* @value: a #JSCValue
*
* Create a new #JSCWeakValue for the JavaScript value referenced by @value.
*
* Returns: (transfer full): a new #JSCWeakValue
*/
JSCWeakValue* jsc_weak_value_new(JSCValue* value)
{
g_return_val_if_fail(JSC_IS_VALUE(value), nullptr);
return JSC_WEAK_VALUE(g_object_new(JSC_TYPE_WEAK_VALUE, "value", value, nullptr));
}
/**
* jsc_weak_value_get_value:
* @weak_value: a #JSCWeakValue
*
* Get a #JSCValue referencing the JavaScript value of @weak_value.
*
* Returns: (transfer full): a new #JSCValue or %NULL if @weak_value was cleared.
*/
JSCValue* jsc_weak_value_get_value(JSCWeakValue* weakValue)
{
g_return_val_if_fail(JSC_IS_WEAK_VALUE(weakValue), nullptr);
JSCWeakValuePrivate* priv = weakValue->priv;
WTF::Locker<JSC::JSLock> locker(priv->lock.get());
RefPtr vm = priv->lock->vm();
if (!vm)
return nullptr;
JSC::JSLockHolder apiLocker(vm.get());
if (!priv->globalObject || priv->weakValueRef.isClear())
return nullptr;
JSC::JSValue value;
if (priv->weakValueRef.isPrimitive())
value = priv->weakValueRef.primitive();
else if (priv->weakValueRef.isString())
value = priv->weakValueRef.string();
else
value = priv->weakValueRef.object();
JSC::JSGlobalObject* globalObject = priv->globalObject.get();
GRefPtr<JSCContext> context = jscContextGetOrCreate(toGlobalRef(globalObject));
return jscContextGetOrCreateValue(context.get(), toRef(globalObject, value)).leakRef();
}
|
