1/*
2 * Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
3 * Copyright (C) 2003-2019 Apple Inc. All rights reserved.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 */
20
21#include "config.h"
22#include "FunctionConstructor.h"
23
24#include "Completion.h"
25#include "ExceptionHelpers.h"
26#include "FunctionPrototype.h"
27#include "JSAsyncFunction.h"
28#include "JSAsyncGeneratorFunction.h"
29#include "JSFunction.h"
30#include "JSGeneratorFunction.h"
31#include "JSGlobalObject.h"
32#include "JSCInlines.h"
33#include <wtf/text/StringBuilder.h>
34
35namespace JSC {
36
37STATIC_ASSERT_IS_TRIVIALLY_DESTRUCTIBLE(FunctionConstructor);
38
39const ClassInfo FunctionConstructor::s_info = { "Function", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(FunctionConstructor) };
40
41static EncodedJSValue JSC_HOST_CALL constructWithFunctionConstructor(ExecState* exec)
42{
43 ArgList args(exec);
44 return JSValue::encode(constructFunction(exec, jsCast<InternalFunction*>(exec->jsCallee())->globalObject(exec->vm()), args, FunctionConstructionMode::Function, exec->newTarget()));
45}
46
47// ECMA 15.3.1 The Function Constructor Called as a Function
48static EncodedJSValue JSC_HOST_CALL callFunctionConstructor(ExecState* exec)
49{
50 ArgList args(exec);
51 return JSValue::encode(constructFunction(exec, jsCast<InternalFunction*>(exec->jsCallee())->globalObject(exec->vm()), args));
52}
53
54FunctionConstructor::FunctionConstructor(VM& vm, Structure* structure)
55 : InternalFunction(vm, structure, callFunctionConstructor, constructWithFunctionConstructor)
56{
57}
58
59void FunctionConstructor::finishCreation(VM& vm, FunctionPrototype* functionPrototype)
60{
61 Base::finishCreation(vm, vm.propertyNames->Function.string(), NameVisibility::Visible, NameAdditionMode::WithoutStructureTransition);
62 putDirectWithoutTransition(vm, vm.propertyNames->prototype, functionPrototype, PropertyAttribute::DontEnum | PropertyAttribute::DontDelete | PropertyAttribute::ReadOnly);
63 putDirectWithoutTransition(vm, vm.propertyNames->length, jsNumber(1), PropertyAttribute::ReadOnly | PropertyAttribute::DontEnum);
64}
65
66// ECMA 15.3.2 The Function Constructor
67JSObject* constructFunction(ExecState* exec, JSGlobalObject* globalObject, const ArgList& args, const Identifier& functionName, const SourceOrigin& sourceOrigin, const String& sourceURL, const TextPosition& position, FunctionConstructionMode functionConstructionMode, JSValue newTarget)
68{
69 VM& vm = exec->vm();
70 auto scope = DECLARE_THROW_SCOPE(vm);
71
72 if (UNLIKELY(!globalObject->evalEnabled())) {
73 throwException(exec, scope, createEvalError(exec, globalObject->evalDisabledErrorMessage()));
74 return nullptr;
75 }
76 RELEASE_AND_RETURN(scope, constructFunctionSkippingEvalEnabledCheck(exec, globalObject, args, functionName, sourceOrigin, sourceURL, position, -1, functionConstructionMode, newTarget));
77}
78
79JSObject* constructFunctionSkippingEvalEnabledCheck(
80 ExecState* exec, JSGlobalObject* globalObject, const ArgList& args,
81 const Identifier& functionName, const SourceOrigin& sourceOrigin, const String& sourceURL,
82 const TextPosition& position, int overrideLineNumber, FunctionConstructionMode functionConstructionMode, JSValue newTarget)
83{
84 VM& vm = exec->vm();
85 auto scope = DECLARE_THROW_SCOPE(vm);
86
87 const char* prefix = nullptr;
88 switch (functionConstructionMode) {
89 case FunctionConstructionMode::Function:
90 prefix = "function ";
91 break;
92 case FunctionConstructionMode::Generator:
93 prefix = "function *";
94 break;
95 case FunctionConstructionMode::Async:
96 prefix = "async function ";
97 break;
98 case FunctionConstructionMode::AsyncGenerator:
99 prefix = "async function*";
100 break;
101 }
102
103 // How we stringify functions is sometimes important for web compatibility.
104 // See https://bugs.webkit.org/show_bug.cgi?id=24350.
105 String program;
106 Optional<int> functionConstructorParametersEndPosition = WTF::nullopt;
107 if (args.isEmpty())
108 program = makeString(prefix, functionName.string(), "() {\n\n}");
109 else if (args.size() == 1) {
110 auto body = args.at(0).toWTFString(exec);
111 RETURN_IF_EXCEPTION(scope, nullptr);
112 program = makeString(prefix, functionName.string(), "() {\n", body, "\n}");
113 } else {
114 StringBuilder builder(StringBuilder::OverflowHandler::RecordOverflow);
115 builder.append(prefix);
116 builder.append(functionName.string());
117
118 builder.append('(');
119 auto viewWithString = args.at(0).toString(exec)->viewWithUnderlyingString(exec);
120 RETURN_IF_EXCEPTION(scope, nullptr);
121 builder.append(viewWithString.view);
122 for (size_t i = 1; !builder.hasOverflowed() && i < args.size() - 1; i++) {
123 builder.appendLiteral(", ");
124 auto viewWithString = args.at(i).toString(exec)->viewWithUnderlyingString(exec);
125 RETURN_IF_EXCEPTION(scope, nullptr);
126 builder.append(viewWithString.view);
127 }
128 if (builder.hasOverflowed()) {
129 throwOutOfMemoryError(exec, scope);
130 return nullptr;
131 }
132
133 functionConstructorParametersEndPosition = builder.length() + 1;
134 builder.appendLiteral(") {\n");
135
136 auto body = args.at(args.size() - 1).toString(exec)->viewWithUnderlyingString(exec);
137 RETURN_IF_EXCEPTION(scope, nullptr);
138 builder.append(body.view);
139 builder.appendLiteral("\n}");
140 if (builder.hasOverflowed()) {
141 throwOutOfMemoryError(exec, scope);
142 return nullptr;
143 }
144 program = builder.toString();
145 }
146
147 SourceCode source = makeSource(program, sourceOrigin, URL({ }, sourceURL), position);
148 JSObject* exception = nullptr;
149 FunctionExecutable* function = FunctionExecutable::fromGlobalCode(functionName, *exec, source, exception, overrideLineNumber, functionConstructorParametersEndPosition);
150 if (UNLIKELY(!function)) {
151 ASSERT(exception);
152 throwException(exec, scope, exception);
153 return nullptr;
154 }
155
156 Structure* structure = nullptr;
157 switch (functionConstructionMode) {
158 case FunctionConstructionMode::Function:
159 structure = JSFunction::selectStructureForNewFuncExp(globalObject, function);
160 break;
161 case FunctionConstructionMode::Generator:
162 structure = globalObject->generatorFunctionStructure();
163 break;
164 case FunctionConstructionMode::Async:
165 structure = globalObject->asyncFunctionStructure();
166 break;
167 case FunctionConstructionMode::AsyncGenerator:
168 structure = globalObject->asyncGeneratorFunctionStructure();
169 break;
170 }
171
172 Structure* subclassStructure = InternalFunction::createSubclassStructure(exec, newTarget, structure);
173 RETURN_IF_EXCEPTION(scope, nullptr);
174
175 switch (functionConstructionMode) {
176 case FunctionConstructionMode::Function:
177 return JSFunction::create(vm, function, globalObject->globalScope(), subclassStructure);
178 case FunctionConstructionMode::Generator:
179 return JSGeneratorFunction::create(vm, function, globalObject->globalScope(), subclassStructure);
180 case FunctionConstructionMode::Async:
181 return JSAsyncFunction::create(vm, function, globalObject->globalScope(), subclassStructure);
182 case FunctionConstructionMode::AsyncGenerator:
183 return JSAsyncGeneratorFunction::create(vm, function, globalObject->globalScope(), subclassStructure);
184 }
185
186 ASSERT_NOT_REACHED();
187 return nullptr;
188}
189
190// ECMA 15.3.2 The Function Constructor
191JSObject* constructFunction(ExecState* exec, JSGlobalObject* globalObject, const ArgList& args, FunctionConstructionMode functionConstructionMode, JSValue newTarget)
192{
193 VM& vm = exec->vm();
194 return constructFunction(exec, globalObject, args, vm.propertyNames->anonymous, exec->callerSourceOrigin(), String(), TextPosition(), functionConstructionMode, newTarget);
195}
196
197} // namespace JSC
198