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.List; 30 import java.util.stream.Collectors; 31 import com.sun.tools.jextract.parser.Parser; 32 import com.sun.tools.jextract.tree.EnumTree; 33 import com.sun.tools.jextract.tree.FieldTree; 34 import com.sun.tools.jextract.tree.LayoutUtils; 35 import com.sun.tools.jextract.tree.HeaderTree; 36 import com.sun.tools.jextract.tree.SimpleTreeVisitor; 37 import com.sun.tools.jextract.tree.StructTree; 38 import com.sun.tools.jextract.tree.Tree; 39 import com.sun.tools.jextract.tree.TreeMaker; 40 import com.sun.tools.jextract.tree.TreePhase; 41 import com.sun.tools.jextract.tree.TreePrinter; 42 import jdk.internal.clang.Cursor; 43 44 /** 45 * This tree visitor handles the tree empty names encountered in the tree 46 * so that subsequent passes need not check tree.name() for empty string. 47 * 48 * 1. Names are generated & set for anonymous structs & unions. 49 * 2. Anonymous (bit) FieldTree instances are removed. 50 */ 51 final class EmptyNameHandler extends SimpleTreeVisitor<Tree, Void> 52 implements TreePhase { 53 private final TreeMaker treeMaker = new TreeMaker(); 54 55 @Override 56 public HeaderTree transform(HeaderTree ht) { 57 return (HeaderTree)ht.accept(this, null); 58 } 59 60 // generate unique name for an empty name 61 private String generateName(Tree tree) { 62 return LayoutUtils.getName(tree); 63 } 64 65 @Override 66 public Tree defaultAction(Tree tree, Void v) { 67 return tree; 68 } 69 70 @Override 71 public Tree visitHeader(HeaderTree ht, Void v) { 72 List<Tree> decls = ht.declarations().stream(). 73 map(decl -> decl.accept(this, null)). 74 collect(Collectors.toList()); 75 return treeMaker.createHeader(ht.cursor(), ht.path(), decls); 76 } 77 78 @Override 79 public Tree visitStruct(StructTree s, Void v) { 80 // Common simple case. No nested names and no anonymous field names. 81 // We just need to check struct name itself is empty or not. 82 if (s.nestedTypes().isEmpty() && !hasAnonymousFields(s)) { 83 /* 84 * Examples: 85 * 86 * struct { int i } x; // global variable of anon. struct type 87 * void func(struct { int x; } p); // param of anon. struct type 88 */ 89 if (s.name().isEmpty()) { 90 return s.withName(generateName(s)); 91 } else { 92 // all fine with this struct 93 return s; 94 } 95 } else { 96 // handle all nested types 97 return renameRecursively(s); 98 } 99 } 100 101 // does the given struct has any anonymous (bit) field? 102 private boolean hasAnonymousFields(StructTree s) { 103 return s.fields().stream().map(f -> f.name().isEmpty()).findFirst().isPresent(); 104 } 105 106 private StructTree renameRecursively(StructTree s) { 107 List<Tree> newDecls = s.declarations().stream().map(decl -> { 108 if (decl instanceof StructTree) { 109 return renameRecursively((StructTree)decl); 110 } else if (decl instanceof FieldTree && decl.name().isEmpty()) { 111 /* 112 * Skip anonymous fields. This happens in the following case: 113 * 114 * struct { 115 * int :23; // anonymous bit field 116 * int x:9; 117 * } 118 */ 119 120 return null; 121 } else { 122 return decl; 123 } 124 }).filter(d -> d != null).collect(Collectors.toList()); 125 126 return s.withNameAndDecls(generateName(s), newDecls); 127 } 128 129 // test main to manually check this visitor 130 public static void main(String[] args) { 131 if (args.length == 0) { 132 System.err.println("Expected a header file"); 133 return; 134 } 135 136 Parser p = new Parser(true); 137 List<Path> paths = Arrays.stream(args).map(Paths::get).collect(Collectors.toList()); 138 Path builtinInc = Paths.get(System.getProperty("java.home"), "conf", "jextract"); 139 List<String> clangArgs = List.of("-I" + builtinInc); 140 List<HeaderTree> headers = p.parse(paths, clangArgs); 141 TreePrinter printer = new TreePrinter(); 142 EmptyNameHandler handler = new EmptyNameHandler(); 143 for (HeaderTree ht : headers) { 144 handler.transform(ht).accept(printer, null); 145 } 146 } 147 }