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 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 boolean isFromSameHeader(Tree def, Tree decl) { 69 SourceLocation locDef = def.location(); 70 SourceLocation locDecl = decl.location(); 71 return locDef != null && locDecl != null && 72 Objects.equals(locDecl.getFileLocation().path(), locDef.getFileLocation().path()); 73 } 74 75 @Override 76 public HeaderTree transform(HeaderTree ht) { 77 // Process all header declarations are collect potential 78 // declarations that will go into transformed HeaderTree 79 // into the this.decls field. 80 ht.accept(this, null); 81 82 // Replace trees from this.decls with Trees found in this.replacements. 83 // We need this two step process so that named StructTree instances 84 // will replace with original unnamed StructTree instances. 85 List<Tree> newDecls = decls.stream().map(tx -> { 86 if (replacements.containsKey(tx.cursor())) { 87 return replacements.get(tx.cursor()); 88 } else { 89 return tx; 90 } 91 }).collect(Collectors.toList()); 92 93 return treeMaker.createHeader(ht.cursor(), ht.path(), newDecls); 94 } 95 96 @Override 97 public Void defaultAction(Tree tree, Void v) { 98 decls.add(tree); 99 return null; 100 } 101 102 @Override 103 public Void visitEnum(EnumTree e, Void v) { 104 /* 105 * If we're seeing a forward/backward declaration of an 106 * enum which is definied elsewhere in this compilation 107 * unit, ignore it. If no definition is found, we want to 108 * leave the declaration so that dummy definition will be 109 * generated. 110 * 111 * Example: 112 * 113 * enum Color ; // <-- forward declaration 114 * struct Point { int i; int j; }; 115 * struct Point3D { int i; int j; int k; }; 116 * struct Point3D; // <-- backward declaration 117 */ 118 119 // include this only if this is a definition or a declaration 120 // for which no definition is found elsewhere in this header. 121 if (e.isDefinition()) { 122 decls.add(e); 123 } else { 124 Optional<Tree> def = e.definition(); 125 if (!def.isPresent() || !isFromSameHeader(def.get(), e)) { 126 decls.add(e); 127 } 128 } 129 return null; 130 } 131 132 @Override 133 public Void visitHeader(HeaderTree ht, Void v) { 134 ht.declarations().forEach(decl -> decl.accept(this, null)); 135 return null; 136 } 137 138 @Override 139 public Void visitStruct(StructTree s, Void v) { 140 List<Tree> oldDecls = decls; 141 List<Tree> structDecls = new ArrayList<>(); 142 try { 143 decls = structDecls; 144 s.declarations().forEach(t -> t.accept(this, null)); 145 } finally { 146 decls = oldDecls; 147 } 148 149 /* 150 * If we're seeing a forward/backward declaration of 151 * a struct which is definied elsewhere in this compilation 152 * unit, ignore it. If no definition is found, we want to 153 * leave the declaration so that dummy definition will be 154 * generated. 155 * 156 * Example: 157 * 158 * struct Point; // <-- forward declaration 159 * struct Point { int i; int j; }; 160 * struct Point3D { int i; int j; int k; }; 161 * struct Point3D; // <-- backward declaration 162 */ 163 164 // include this only if this is a definition or a declaration 165 // for which no definition is found elsewhere in this header. 166 if (s.isDefinition()) { 167 decls.add(s.withNameAndDecls(s.name(), structDecls)); 168 } else { 169 Optional<Tree> def = s.definition(); 170 if (!def.isPresent() || !isFromSameHeader(def.get(), s)) { 171 decls.add(s.withNameAndDecls(s.name(), structDecls)); 172 } 173 } 174 return null; 175 } 176 177 @Override 178 public Void visitTypedef(TypedefTree tt, Void v) { 179 Optional<Tree> def = tt.typeDefinition(); 180 if (def.isPresent()) { 181 Tree defTree = def.get(); 182 if (defTree instanceof StructTree && defTree.name().isEmpty()) { 183 /* 184 * typedef struct { int x; int y; } Point 185 * 186 * is mapped to two Cursors by clang. First one for anonymous struct decl. 187 * and second one for typedef decl. We map it as a single named struct 188 * declaration. 189 */ 190 replacements.put(defTree.cursor(), ((StructTree)defTree).withName(tt.name())); 191 return null; 192 } else if (defTree.name().equals(tt.name())) { 193 /* 194 * Remove redundant typedef like: 195 * 196 * typedef struct Point { int x; int y; } Point 197 * typedef enum Color { R, G, B} Color 198 * typedef struct Undef Undef 199 */ 200 return null; 201 } 202 } 203 204 decls.add(tt); 205 return null; 206 } 207 208 // test main to manually check this visitor 209 public static void main(String[] args) { 210 if (args.length == 0) { 211 System.err.println("Expected a header file"); 212 return; 213 } 214 215 Context context = new Context(); 216 Parser p = new Parser(context, true); 217 List<Path> paths = Arrays.stream(args).map(Paths::get).collect(Collectors.toList()); 218 Path builtinInc = Paths.get(System.getProperty("java.home"), "conf", "jextract"); 219 List<String> clangArgs = List.of("-I" + builtinInc); 220 List<HeaderTree> headers = p.parse(paths, clangArgs); 221 TreePrinter printer = new TreePrinter(); 222 TypedefHandler handler = new TypedefHandler(); 223 for (HeaderTree ht : headers) { 224 handler.transform(ht).accept(printer, null); 225 } 226 } 227 } --- EOF ---