1 | /* |
2 | * Copyright (C) 2015 Apple Inc. All rights reserved. |
3 | * |
4 | * Redistribution and use in source and binary forms, with or without |
5 | * modification, are permitted provided that the following conditions |
6 | * are met: |
7 | * 1. Redistributions of source code must retain the above copyright |
8 | * notice, this list of conditions and the following disclaimer. |
9 | * 2. Redistributions in binary form must reproduce the above copyright |
10 | * notice, this list of conditions and the following disclaimer in the |
11 | * documentation and/or other materials provided with the distribution. |
12 | * |
13 | * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
14 | * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
15 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
16 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
17 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
18 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
20 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
21 | * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
23 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
24 | */ |
25 | |
26 | #pragma once |
27 | |
28 | #include "Identifier.h" |
29 | #include "JSDestructibleObject.h" |
30 | #include <wtf/ListHashSet.h> |
31 | |
32 | namespace JSC { |
33 | |
34 | class JSModuleEnvironment; |
35 | class JSModuleNamespaceObject; |
36 | class JSMap; |
37 | |
38 | // Based on the Source Text Module Record |
39 | // http://www.ecma-international.org/ecma-262/6.0/#sec-source-text-module-records |
40 | class AbstractModuleRecord : public JSDestructibleObject { |
41 | friend class LLIntOffsetsExtractor; |
42 | public: |
43 | typedef JSDestructibleObject Base; |
44 | |
45 | // https://tc39.github.io/ecma262/#sec-source-text-module-records |
46 | struct ExportEntry { |
47 | enum class Type { |
48 | Local, |
49 | Indirect |
50 | }; |
51 | |
52 | static ExportEntry createLocal(const Identifier& exportName, const Identifier& localName); |
53 | static ExportEntry createIndirect(const Identifier& exportName, const Identifier& importName, const Identifier& moduleName); |
54 | |
55 | Type type; |
56 | Identifier exportName; |
57 | Identifier moduleName; |
58 | Identifier importName; |
59 | Identifier localName; |
60 | }; |
61 | |
62 | enum class ImportEntryType { Single, Namespace }; |
63 | struct ImportEntry { |
64 | ImportEntryType type; |
65 | Identifier moduleRequest; |
66 | Identifier importName; |
67 | Identifier localName; |
68 | }; |
69 | |
70 | typedef WTF::ListHashSet<RefPtr<UniquedStringImpl>, IdentifierRepHash> OrderedIdentifierSet; |
71 | typedef HashMap<RefPtr<UniquedStringImpl>, ImportEntry, IdentifierRepHash, HashTraits<RefPtr<UniquedStringImpl>>> ImportEntries; |
72 | typedef HashMap<RefPtr<UniquedStringImpl>, ExportEntry, IdentifierRepHash, HashTraits<RefPtr<UniquedStringImpl>>> ExportEntries; |
73 | |
74 | DECLARE_EXPORT_INFO; |
75 | |
76 | void appendRequestedModule(const Identifier&); |
77 | void addStarExportEntry(const Identifier&); |
78 | void addImportEntry(const ImportEntry&); |
79 | void addExportEntry(const ExportEntry&); |
80 | |
81 | Optional<ImportEntry> tryGetImportEntry(UniquedStringImpl* localName); |
82 | Optional<ExportEntry> tryGetExportEntry(UniquedStringImpl* exportName); |
83 | |
84 | const Identifier& moduleKey() const { return m_moduleKey; } |
85 | const OrderedIdentifierSet& requestedModules() const { return m_requestedModules; } |
86 | const ExportEntries& exportEntries() const { return m_exportEntries; } |
87 | const ImportEntries& importEntries() const { return m_importEntries; } |
88 | const OrderedIdentifierSet& starExportEntries() const { return m_starExportEntries; } |
89 | |
90 | void dump(); |
91 | |
92 | struct Resolution { |
93 | enum class Type { Resolved, NotFound, Ambiguous, Error }; |
94 | |
95 | static Resolution notFound(); |
96 | static Resolution error(); |
97 | static Resolution ambiguous(); |
98 | |
99 | Type type; |
100 | AbstractModuleRecord* moduleRecord; |
101 | Identifier localName; |
102 | }; |
103 | |
104 | Resolution resolveExport(ExecState*, const Identifier& exportName); |
105 | Resolution resolveImport(ExecState*, const Identifier& localName); |
106 | |
107 | AbstractModuleRecord* hostResolveImportedModule(ExecState*, const Identifier& moduleName); |
108 | |
109 | JSModuleNamespaceObject* getModuleNamespace(ExecState*); |
110 | |
111 | JSModuleEnvironment* moduleEnvironment() |
112 | { |
113 | ASSERT(m_moduleEnvironment); |
114 | return m_moduleEnvironment.get(); |
115 | } |
116 | |
117 | JSModuleEnvironment* moduleEnvironmentMayBeNull() |
118 | { |
119 | return m_moduleEnvironment.get(); |
120 | } |
121 | |
122 | void link(ExecState*, JSValue scriptFetcher); |
123 | JS_EXPORT_PRIVATE JSValue evaluate(ExecState*); |
124 | |
125 | protected: |
126 | AbstractModuleRecord(VM&, Structure*, const Identifier&); |
127 | void finishCreation(ExecState*, VM&); |
128 | |
129 | static void visitChildren(JSCell*, SlotVisitor&); |
130 | static void destroy(JSCell*); |
131 | |
132 | WriteBarrier<JSModuleEnvironment> m_moduleEnvironment; |
133 | |
134 | private: |
135 | struct ResolveQuery; |
136 | static Resolution resolveExportImpl(ExecState*, const ResolveQuery&); |
137 | Optional<Resolution> tryGetCachedResolution(UniquedStringImpl* exportName); |
138 | void cacheResolution(UniquedStringImpl* exportName, const Resolution&); |
139 | |
140 | // The loader resolves the given module name to the module key. The module key is the unique value to represent this module. |
141 | Identifier m_moduleKey; |
142 | |
143 | // Currently, we don't keep the occurrence order of the import / export entries. |
144 | // So, we does not guarantee the order of the errors. |
145 | // e.g. The import declaration that occurr later than the another import declaration may |
146 | // throw the error even if the former import declaration also has the invalid content. |
147 | // |
148 | // import ... // (1) this has some invalid content. |
149 | // import ... // (2) this also has some invalid content. |
150 | // |
151 | // In the above case, (2) may throw the error earlier than (1) |
152 | // |
153 | // But, in all the cases, we will throw the syntax error. So except for the content of the syntax error, |
154 | // there are no difference. |
155 | |
156 | // Map localName -> ImportEntry. |
157 | ImportEntries m_importEntries; |
158 | |
159 | // Map exportName -> ExportEntry. |
160 | ExportEntries m_exportEntries; |
161 | |
162 | // Save the occurrence order since resolveExport requires it. |
163 | OrderedIdentifierSet m_starExportEntries; |
164 | |
165 | // Save the occurrence order since the module loader loads and runs the modules in this order. |
166 | // http://www.ecma-international.org/ecma-262/6.0/#sec-moduleevaluation |
167 | OrderedIdentifierSet m_requestedModules; |
168 | |
169 | WriteBarrier<JSMap> m_dependenciesMap; |
170 | |
171 | WriteBarrier<JSModuleNamespaceObject> m_moduleNamespaceObject; |
172 | |
173 | // We assume that all the AbstractModuleRecord are retained by JSModuleLoader's registry. |
174 | // So here, we don't visit each object for GC. The resolution cache map caches the once |
175 | // looked up correctly resolved resolution, since (1) we rarely looked up the non-resolved one, |
176 | // and (2) if we cache all the attempts the size of the map becomes infinitely large. |
177 | typedef HashMap<RefPtr<UniquedStringImpl>, Resolution, IdentifierRepHash, HashTraits<RefPtr<UniquedStringImpl>>> Resolutions; |
178 | Resolutions m_resolutionCache; |
179 | }; |
180 | |
181 | } // namespace JSC |
182 | |