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 visitField(FieldTree t, Void aVoid) {
  80         if (t.name().isEmpty()) {






























  81             /*
  82              * Skip anonymous fields. This happens in the following case:
  83              *
  84              * struct {
  85              *    int  :23; // anonymous bit field
  86              *    int x:9;
  87              * }
  88              */
  89 
  90             return null;
  91         } else {
  92             return t;
  93         }
  94     }
  95 
  96     @Override
  97     public Tree visitStruct(StructTree s, Void v) {
  98         List<Tree> newDecls = s.declarations().stream()
  99                 .map(decl -> decl.accept(this, null))
 100                 .filter(d -> d != null)
 101                 .collect(Collectors.toList());
 102 
 103         return s.withNameAndDecls(generateName(s), newDecls);
 104     }
 105 
 106     // test main to manually check this visitor
 107     public static void main(String[] args) {
 108         if (args.length == 0) {
 109             System.err.println("Expected a header file");
 110             return;
 111         }
 112 
 113         Context context = new Context();
 114         Parser p = new Parser(context,true);
 115         List<Path> paths = Arrays.stream(args).map(Paths::get).collect(Collectors.toList());
 116         Path builtinInc = Paths.get(System.getProperty("java.home"), "conf", "jextract");
 117         List<String> clangArgs = List.of("-I" + builtinInc);
 118         List<HeaderTree> headers = p.parse(paths, clangArgs);
 119         TreePrinter printer = new TreePrinter();
 120         EmptyNameHandler handler = new EmptyNameHandler();
 121         for (HeaderTree ht : headers) {
 122             handler.transform(ht).accept(printer, null);
 123         }
 124     }
 125 }
--- EOF ---