1 /*
2 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23 package com.sun.tools.jextract;
24
25 import java.nio.file.Files;
26 import java.nio.file.Path;
27 import java.util.ArrayList;
28 import java.util.List;
29 import java.util.Set;
30 import java.util.logging.Level;
31
32 import com.sun.tools.jextract.parser.MacroParser;
33 import com.sun.tools.jextract.tree.Tree;
34 import com.sun.tools.jextract.tree.EnumTree;
35 import com.sun.tools.jextract.tree.FieldTree;
36 import com.sun.tools.jextract.tree.FunctionTree;
37 import com.sun.tools.jextract.tree.MacroTree;
38 import com.sun.tools.jextract.tree.VarTree;
39
40 /**
41 * This extended factory generates a class with only static methods and fields. A native
42 * library interface instance (of the given header file) is kept as a static private field.
43 * One static method is generated for every library interface method. Enum and macro constants
44 * are mapped to static final fields. By importing the "static forwarder" class, the user code
45 * looks more or less like C code. Libraries.bind and header interface usage is hidden.
46 */
47 final class JavaSourceFactoryExt extends JavaSourceFactory {
48 // field name for the header interface instance.
49 private static final String STATICS_LIBRARY_FIELD_NAME = "_theLibrary";
50 private final JavaSourceBuilderExt header_jsb;
51 private final List<JavaSourceBuilderExt> enums;
52
53 JavaSourceFactoryExt(Context ctx, HeaderFile header) {
54 super(ctx, header);
55 log.print(Level.INFO, () -> "Instantiate StaticForwarderGenerator for " + header.path);
56 header_jsb = new JavaSourceBuilderExt();
57 enums = new ArrayList<>();
58 }
59
60 @Override
61 public void generate(List<Tree> decls) {
62 header_jsb.addPackagePrefix(headerFile.pkgName);
63 String ifaceClsName = headerFile.headerClsName;
64 String forwarderName = headerFile.staticForwarderClsName;
65 header_jsb.classBegin(forwarderName, false);
66
67 header_jsb.addLibraryField(ifaceClsName, STATICS_LIBRARY_FIELD_NAME);
68 header_jsb.emitScopeAccessor(STATICS_LIBRARY_FIELD_NAME);
69
70 super.generate(decls);
71 enums.forEach(header_jsb::addNestedType);
72
73 header_jsb.classEnd();
74 String src = header_jsb.build();
75 try {
76 Path srcPath = srcDir.resolve(forwarderName + ".java");
77 Files.write(srcPath, List.of(src));
78 } catch (Exception ex) {
79 handleException(ex);
80 }
81 }
82
83 @Override
84 public Boolean visitVar(VarTree varTree, JType jt) {
85 if (super.visitVar(varTree, jt)) {
86 String fieldName = varTree.name();
87 assert !fieldName.isEmpty();
88 header_jsb.emitStaticForwarder(varTree, jt, STATICS_LIBRARY_FIELD_NAME);
89 return true;
90 } else {
91 return false;
92 }
93 }
94
95 @Override
96 public Boolean visitEnum(EnumTree enumTree, JType jt) {
97 if (super.visitEnum(enumTree, jt)) {
98 if (enumTree.name().isEmpty()) {
99 enumTree.constants().forEach(constant -> addConstant(header_jsb, constant.name(),
100 headerFile.dictionary().lookup(constant.type()),
101 constant.enumConstant().get()));
102 } else {
103 JavaSourceBuilderExt enumBuilder = new JavaSourceBuilderExt(header_jsb.align() + 1);
104 enumBuilder.interfaceBegin(enumTree.name(), true);
105 enumTree.constants().forEach(constant -> addConstant(enumBuilder, constant.name(),
106 headerFile.dictionary().lookup(constant.type()),
107 constant.enumConstant().get()));
108 enumBuilder.interfaceEnd();
109 enums.add(enumBuilder);
110 }
111 return true;
112 } else {
113 return false;
114 }
115 }
116
117 @Override
118 public Boolean visitFunction(FunctionTree funcTree, JType jt) {
119 if (super.visitFunction(funcTree, jt)) {
120 header_jsb.emitStaticForwarder(funcTree, (JType.Function)jt, STATICS_LIBRARY_FIELD_NAME);
121 return true;
122 } else {
123 return false;
124 }
125 }
126
127 @Override
128 public Boolean visitMacro(MacroTree macroTree, JType jt) {
129 if (super.visitMacro(macroTree, jt)) {
130 String name = macroTree.name();
131 MacroParser.Macro macro = macroTree.macro().get();
132 log.print(Level.FINE, () -> "Adding macro " + name);
133 addConstant(header_jsb, Utils.toMacroName(name), macro.type(), macro.value());
134 return true;
135 } else {
136 return false;
137 }
138 }
139
140 private void addConstant(JavaSourceBuilderExt jsb, String name, JType type, Object value) {
141 Object constantValue = makeConstantValue(type, value);
142 jsb.addField(name, type, constantValue, STATICS_LIBRARY_FIELD_NAME);
143 }
144
145 private Object makeConstantValue(JType type, Object value) {
146 switch (type.getDescriptor()) {
147 case "Z":
148 return ((long)value) != 0;
149 case "C":
150 return (char)(long)value;
151 case "B":
152 return (byte)(long)value;
153 case "S":
154 return (short)(long)value;
155 case "I":
156 return (int)(long)value;
157 case "F":
158 return (float)(double)value;
159 case "J": case "D":
160 return value;
161 default:
162 return null;
163 }
164 }
165 }