1/*
2 *  Copyright (C) 1999-2002 Harri Porten (porten@kde.org)
3 *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
4 *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
5 *  Copyright (C) 2007 Cameron Zwarich (cwzwarich@uwaterloo.ca)
6 *  Copyright (C) 2007 Maks Orlovich
7 *
8 *  This library is free software; you can redistribute it and/or
9 *  modify it under the terms of the GNU Library General Public
10 *  License as published by the Free Software Foundation; either
11 *  version 2 of the License, or (at your option) any later version.
12 *
13 *  This library is distributed in the hope that it will be useful,
14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 *  Library General Public License for more details.
17 *
18 *  You should have received a copy of the GNU Library General Public License
19 *  along with this library; see the file COPYING.LIB.  If not, write to
20 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 *  Boston, MA 02110-1301, USA.
22 *
23 */
24
25#include "config.h"
26#include "JSFunction.h"
27
28#include "CodeBlock.h"
29#include "CommonIdentifiers.h"
30#include "CallFrame.h"
31#include "FunctionPrototype.h"
32#include "JSGlobalObject.h"
33#include "Interpreter.h"
34#include "ObjectPrototype.h"
35#include "Parser.h"
36#include "PropertyNameArray.h"
37#include "ScopeChainMark.h"
38
39using namespace WTF;
40using namespace Unicode;
41
42namespace JSC {
43
44ASSERT_CLASS_FITS_IN_CELL(JSFunction);
45
46const ClassInfo JSFunction::info = { "Function", &InternalFunction::info, 0, 0 };
47
48bool JSFunction::isHostFunctionNonInline() const
49{
50    return isHostFunction();
51}
52
53JSFunction::JSFunction(NonNullPassRefPtr<Structure> structure)
54    : Base(structure)
55    , m_executable(adoptRef(new VPtrHackExecutable()))
56{
57}
58
59JSFunction::JSFunction(ExecState* exec, NonNullPassRefPtr<Structure> structure, int length, const Identifier& name, NativeFunction func)
60    : Base(&exec->globalData(), structure, name)
61#if ENABLE(JIT)
62    , m_executable(adoptRef(new NativeExecutable(exec)))
63#endif
64{
65#if ENABLE(JIT)
66    setNativeFunction(func);
67    putDirect(exec->propertyNames().length, jsNumber(exec, length), DontDelete | ReadOnly | DontEnum);
68#else
69    UNUSED_PARAM(length);
70    UNUSED_PARAM(func);
71    ASSERT_NOT_REACHED();
72#endif
73}
74
75JSFunction::JSFunction(ExecState* exec, NonNullPassRefPtr<FunctionExecutable> executable, ScopeChainNode* scopeChainNode)
76    : Base(&exec->globalData(), exec->lexicalGlobalObject()->functionStructure(), executable->name())
77    , m_executable(executable)
78{
79    setScopeChain(scopeChainNode);
80}
81
82JSFunction::~JSFunction()
83{
84    ASSERT(vptr() == JSGlobalData::jsFunctionVPtr);
85
86    // JIT code for other functions may have had calls linked directly to the code for this function; these links
87    // are based on a check for the this pointer value for this JSFunction - which will no longer be valid once
88    // this memory is freed and may be reused (potentially for another, different JSFunction).
89    if (!isHostFunction()) {
90#if ENABLE(JIT_OPTIMIZE_CALL)
91        ASSERT(m_executable);
92        if (jsExecutable()->isGenerated())
93            jsExecutable()->generatedBytecode().unlinkCallers();
94#endif
95        scopeChain().~ScopeChain(); // FIXME: Don't we need to do this in the interpreter too?
96    }
97}
98
99void JSFunction::markChildren(MarkStack& markStack)
100{
101    Base::markChildren(markStack);
102    if (!isHostFunction()) {
103        jsExecutable()->markAggregate(markStack);
104        scopeChain().markAggregate(markStack);
105    }
106}
107
108CallType JSFunction::getCallData(CallData& callData)
109{
110    if (isHostFunction()) {
111        callData.native.function = nativeFunction();
112        return CallTypeHost;
113    }
114    callData.js.functionExecutable = jsExecutable();
115    callData.js.scopeChain = scopeChain().node();
116    return CallTypeJS;
117}
118
119JSValue JSFunction::call(ExecState* exec, JSValue thisValue, const ArgList& args)
120{
121    ASSERT(!isHostFunction());
122    return exec->interpreter()->execute(jsExecutable(), exec, this, thisValue.toThisObject(exec), args, scopeChain().node(), exec->exceptionSlot());
123}
124
125JSValue JSFunction::argumentsGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
126{
127    JSFunction* thisObj = asFunction(slot.slotBase());
128    ASSERT(!thisObj->isHostFunction());
129    return exec->interpreter()->retrieveArguments(exec, thisObj);
130}
131
132JSValue JSFunction::callerGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
133{
134    JSFunction* thisObj = asFunction(slot.slotBase());
135    ASSERT(!thisObj->isHostFunction());
136    return exec->interpreter()->retrieveCaller(exec, thisObj);
137}
138
139JSValue JSFunction::lengthGetter(ExecState* exec, const Identifier&, const PropertySlot& slot)
140{
141    JSFunction* thisObj = asFunction(slot.slotBase());
142    ASSERT(!thisObj->isHostFunction());
143    return jsNumber(exec, thisObj->jsExecutable()->parameterCount());
144}
145
146bool JSFunction::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
147{
148    if (isHostFunction())
149        return Base::getOwnPropertySlot(exec, propertyName, slot);
150
151    if (propertyName == exec->propertyNames().prototype) {
152        JSValue* location = getDirectLocation(propertyName);
153
154        if (!location) {
155            JSObject* prototype = new (exec) JSObject(scopeChain().globalObject()->emptyObjectStructure());
156            prototype->putDirect(exec->propertyNames().constructor, this, DontEnum);
157            putDirect(exec->propertyNames().prototype, prototype, DontDelete);
158            location = getDirectLocation(propertyName);
159        }
160
161        slot.setValueSlot(this, location, offsetForLocation(location));
162    }
163
164    if (propertyName == exec->propertyNames().arguments) {
165        slot.setCustom(this, argumentsGetter);
166        return true;
167    }
168
169    if (propertyName == exec->propertyNames().length) {
170        slot.setCustom(this, lengthGetter);
171        return true;
172    }
173
174    if (propertyName == exec->propertyNames().caller) {
175        slot.setCustom(this, callerGetter);
176        return true;
177    }
178
179    return Base::getOwnPropertySlot(exec, propertyName, slot);
180}
181
182    bool JSFunction::getOwnPropertyDescriptor(ExecState* exec, const Identifier& propertyName, PropertyDescriptor& descriptor)
183    {
184        if (isHostFunction())
185            return Base::getOwnPropertyDescriptor(exec, propertyName, descriptor);
186
187        if (propertyName == exec->propertyNames().prototype) {
188            PropertySlot slot;
189            getOwnPropertySlot(exec, propertyName, slot);
190            return Base::getOwnPropertyDescriptor(exec, propertyName, descriptor);
191        }
192
193        if (propertyName == exec->propertyNames().arguments) {
194            descriptor.setDescriptor(exec->interpreter()->retrieveArguments(exec, this), ReadOnly | DontEnum | DontDelete);
195            return true;
196        }
197
198        if (propertyName == exec->propertyNames().length) {
199            descriptor.setDescriptor(jsNumber(exec, jsExecutable()->parameterCount()), ReadOnly | DontEnum | DontDelete);
200            return true;
201        }
202
203        if (propertyName == exec->propertyNames().caller) {
204            descriptor.setDescriptor(exec->interpreter()->retrieveCaller(exec, this), ReadOnly | DontEnum | DontDelete);
205            return true;
206        }
207
208        return Base::getOwnPropertyDescriptor(exec, propertyName, descriptor);
209    }
210
211void JSFunction::getOwnPropertyNames(ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
212{
213    if (!isHostFunction() && (mode == IncludeDontEnumProperties)) {
214        propertyNames.add(exec->propertyNames().arguments);
215        propertyNames.add(exec->propertyNames().callee);
216        propertyNames.add(exec->propertyNames().caller);
217        propertyNames.add(exec->propertyNames().length);
218    }
219    Base::getOwnPropertyNames(exec, propertyNames, mode);
220}
221
222void JSFunction::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
223{
224    if (isHostFunction()) {
225        Base::put(exec, propertyName, value, slot);
226        return;
227    }
228    if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
229        return;
230    Base::put(exec, propertyName, value, slot);
231}
232
233bool JSFunction::deleteProperty(ExecState* exec, const Identifier& propertyName)
234{
235    if (isHostFunction())
236        return Base::deleteProperty(exec, propertyName);
237    if (propertyName == exec->propertyNames().arguments || propertyName == exec->propertyNames().length)
238        return false;
239    return Base::deleteProperty(exec, propertyName);
240}
241
242// ECMA 13.2.2 [[Construct]]
243ConstructType JSFunction::getConstructData(ConstructData& constructData)
244{
245    if (isHostFunction())
246        return ConstructTypeNone;
247    constructData.js.functionExecutable = jsExecutable();
248    constructData.js.scopeChain = scopeChain().node();
249    return ConstructTypeJS;
250}
251
252JSObject* JSFunction::construct(ExecState* exec, const ArgList& args)
253{
254    ASSERT(!isHostFunction());
255    Structure* structure;
256    JSValue prototype = get(exec, exec->propertyNames().prototype);
257    if (prototype.isObject())
258        structure = asObject(prototype)->inheritorID();
259    else
260        structure = exec->lexicalGlobalObject()->emptyObjectStructure();
261    JSObject* thisObj = new (exec) JSObject(structure);
262
263    JSValue result = exec->interpreter()->execute(jsExecutable(), exec, this, thisObj, args, scopeChain().node(), exec->exceptionSlot());
264    if (exec->hadException() || !result.isObject())
265        return thisObj;
266    return asObject(result);
267}
268
269} // namespace JSC
270