1 /* 2 * Copyright (c) 2018, 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.Path; 26 import java.nio.file.Paths; 27 import java.util.ArrayList; 28 import java.util.Arrays; 29 import java.util.HashMap; 30 import java.util.List; 31 import java.util.Map; 32 import java.util.Objects; 33 import java.util.Optional; 34 import java.util.stream.Collectors; 35 import com.sun.tools.jextract.parser.Parser; 36 import com.sun.tools.jextract.tree.EnumTree; 37 import com.sun.tools.jextract.tree.HeaderTree; 38 import com.sun.tools.jextract.tree.SimpleTreeVisitor; 39 import com.sun.tools.jextract.tree.StructTree; 40 import com.sun.tools.jextract.tree.Tree; 41 import com.sun.tools.jextract.tree.TreeMaker; 42 import com.sun.tools.jextract.tree.TreePhase; 43 import com.sun.tools.jextract.tree.TreePrinter; 44 import com.sun.tools.jextract.tree.TypedefTree; 45 import jdk.internal.clang.Cursor; 46 import jdk.internal.clang.SourceLocation; 47 48 /** 49 * This visitor handles certain typedef declarations. 50 * 51 * 1. Remove redundant typedefs. 52 * 2. Rename typedef'ed anonymous type definitions like 53 * typedef struct { int x; int y; } Point; 54 * 3. Remove redundant struct/union/enum forward/backward declarations 55 */ 56 final class TypedefHandler extends SimpleTreeVisitor<Void, Void> 57 implements TreePhase { 58 private final TreeMaker treeMaker = new TreeMaker(); 59 60 // Potential Tree instances that will go into transformed HeaderTree 61 // are collected in this list. 62 private final List<Tree> decls = new ArrayList<>(); 63 64 // Tree instances that are to be replaced from "decls" list are 65 // saved in the following Map. 66 private final Map<Cursor, Tree> replacements = new HashMap<>(); 67 68 private Path headerPath; 69 70 private static boolean isFromPath(Tree tree, Path path) { 71 SourceLocation loc = tree.location(); 72 return loc != null? Objects.equals(path, loc.getFileLocation().path()) : false; 73 } 74 75 private boolean isFromThisHeader(Tree tree) { 76 return isFromPath(tree, headerPath); 77 } 78 79 @Override 80 public HeaderTree transform(HeaderTree ht) { 81 this.headerPath = ht.path(); 82 // Process all header declarations are collect potential 83 // declarations that will go into transformed HeaderTree 84 // into the this.decls field. 85 ht.accept(this, null); 86 87 // Replace trees from this.decls with Trees found in this.replacements. 88 // We need this two step process so that named StructTree instances 89 // will replace with original unnamed StructTree instances. 90 List<Tree> newDecls = decls.stream().map(tx -> { 91 if (replacements.containsKey(tx.cursor())) { 92 return replacements.get(tx.cursor()); 93 } else { 94 return tx; 95 } 96 }).collect(Collectors.toList()); 97 98 return treeMaker.createHeader(ht.cursor(), ht.path(), newDecls); 99 } 100 101 @Override 102 public Void defaultAction(Tree tree, Void v) { 103 decls.add(tree); 104 return null; 105 } 106 107 @Override 108 public Void visitEnum(EnumTree e, Void v) { 109 /* 110 * If we're seeing a forward/backward declaration of an 111 * enum which is definied elsewhere in this compilation 112 * unit, ignore it. If no definition is found, we want to 113 * leave the declaration so that dummy definition will be 114 * generated. 115 * 116 * Example: 117 * 118 * enum Color ; // <-- forward declaration 119 * struct Point { int i; int j; }; 120 * struct Point3D { int i; int j; int k; }; 121 * struct Point3D; // <-- backward declaration 122 */ 123 124 // include this only if this is a definition or a declaration 125 // for which no definition is found elsewhere in this header. 126 if (e.isDefinition()) { 127 decls.add(e); 128 } else { 129 Optional<Tree> def = e.definition(); 130 if (!def.isPresent() || !isFromThisHeader(def.get())) { 131 decls.add(e); 132 } 133 } 134 return null; 135 } 136 137 @Override 138 public Void visitHeader(HeaderTree ht, Void v) { 139 ht.declarations().forEach(decl -> decl.accept(this, null)); 140 return null; 141 } 142 143 @Override 144 public Void visitStruct(StructTree s, Void v) { 145 /* 146 * If we're seeing a forward/backward declaration of 147 * a struct which is definied elsewhere in this compilation 148 * unit, ignore it. If no definition is found, we want to 149 * leave the declaration so that dummy definition will be 150 * generated. 151 * 152 * Example: 153 * 154 * struct Point; // <-- forward declaration 155 * struct Point { int i; int j; }; 156 * struct Point3D { int i; int j; int k; }; 157 * struct Point3D; // <-- backward declaration 158 */ 159 160 // include this only if this is a definition or a declaration 161 // for which no definition is found elsewhere in this header. 162 if (s.isDefinition()) { 163 decls.add(s); 164 } else { 165 Optional<Tree> def = s.definition(); 166 if (!def.isPresent() || !isFromThisHeader(def.get())) { 167 decls.add(s); 168 } 169 } 170 return null; 171 } 172 173 @Override 174 public Void visitTypedef(TypedefTree tt, Void v) { 175 Optional<Tree> def = tt.typeDefinition(); 176 if (def.isPresent()) { 177 Tree defTree = def.get(); 178 if (defTree instanceof StructTree && defTree.name().isEmpty()) { 179 /* 180 * typedef struct { int x; int y; } Point 181 * 182 * is mapped to two Cursors by clang. First one for anonymous struct decl. 183 * and second one for typedef decl. We map it as a single named struct 184 * declaration. 185 */ 186 replacements.put(defTree.cursor(), ((StructTree)defTree).withName(tt.name())); 187 return null; 188 } else if (defTree.name().equals(tt.name())) { 189 /* 190 * Remove redundant typedef like: 191 * 192 * typedef struct Point { int x; int y; } Point 193 * typedef enum Color { R, G, B} Color 194 * typedef struct Undef Undef 195 */ 196 return null; 197 } 198 } 199 200 decls.add(tt); 201 return null; 202 } 203 204 // test main to manually check this visitor 205 public static void main(String[] args) { 206 if (args.length == 0) { 207 System.err.println("Expected a header file"); 208 return; 209 } 210 211 Parser p = new Parser(true); 212 List<Path> paths = Arrays.stream(args).map(Paths::get).collect(Collectors.toList()); 213 Path builtinInc = Paths.get(System.getProperty("java.home"), "conf", "jextract"); 214 List<String> clangArgs = List.of("-I" + builtinInc); 215 List<HeaderTree> headers = p.parse(paths, clangArgs); 216 TreePrinter printer = new TreePrinter(); 217 TypedefHandler handler = new TypedefHandler(); 218 for (HeaderTree ht : headers) { 219 handler.transform(ht).accept(printer, null); 220 } 221 } 222 }