1 /*
2  * Copyright (c) 2013, 2015, 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 
24 /*
25  * @test
26  * @bug 8029800
27  * @summary String.toLowerCase()/toUpperCase is generally dangerous, check it is not used in langtools
28  * @modules jdk.jdeps/com.sun.tools.classfile
29  */
30 
31 import java.io.*;
32 import java.util.*;
33 import javax.tools.*;
34 import com.sun.tools.classfile.*;
35 import com.sun.tools.classfile.ConstantPool.CONSTANT_Methodref_info;
36 
37 public class NoStringToLower {
main(String... args)38     public static void main(String... args) throws Exception {
39         NoStringToLower c = new NoStringToLower();
40         if (c.run(args))
41             return;
42 
43         if (is_jtreg())
44             throw new Exception(c.errors + " errors occurred");
45         else
46             System.exit(1);
47     }
48 
is_jtreg()49     static boolean is_jtreg() {
50         return (System.getProperty("test.src") != null);
51     }
52 
53     /**
54      * Main entry point.
55      */
run(String... args)56     boolean run(String... args) throws Exception {
57         JavaCompiler c = ToolProvider.getSystemJavaCompiler();
58         try (JavaFileManager fm = c.getStandardFileManager(null, null, null)) {
59             JavaFileManager.Location javacLoc = findJavacLocation(fm);
60             String[] pkgs = {
61                 "javax.annotation.processing",
62                 "javax.lang.model",
63                 "javax.tools",
64                 "com.sun.source",
65                 "com.sun.tools.classfile",
66                 "com.sun.tools.doclet",
67                 "com.sun.tools.doclint",
68                 "com.sun.tools.javac",
69                 "com.sun.tools.javadoc",
70                 "com.sun.tools.javah",
71                 "com.sun.tools.javap",
72                 "com.sun.tools.jdeps",
73                 "com.sun.tools.sjavac"
74             };
75             for (String pkg: pkgs) {
76                 for (JavaFileObject fo: fm.list(javacLoc,
77                         pkg, EnumSet.of(JavaFileObject.Kind.CLASS), true)) {
78                     scan(fo);
79                 }
80             }
81 
82             return (errors == 0);
83         }
84     }
85 
86     // depending on how the test is run, javac may be on bootclasspath or classpath
findJavacLocation(JavaFileManager fm)87     JavaFileManager.Location findJavacLocation(JavaFileManager fm) {
88         JavaFileManager.Location[] locns =
89             { StandardLocation.PLATFORM_CLASS_PATH, StandardLocation.CLASS_PATH };
90         try {
91             for (JavaFileManager.Location l: locns) {
92                 JavaFileObject fo = fm.getJavaFileForInput(l,
93                     "com.sun.tools.javac.Main", JavaFileObject.Kind.CLASS);
94                 if (fo != null)
95                     return l;
96             }
97         } catch (IOException e) {
98             throw new Error(e);
99         }
100         throw new IllegalStateException("Cannot find javac");
101     }
102 
103     /**
104      * Verify there are no references to String.toLowerCase() in a class file.
105      */
scan(JavaFileObject fo)106     void scan(JavaFileObject fo) throws IOException {
107         InputStream in = fo.openInputStream();
108         try {
109             ClassFile cf = ClassFile.read(in);
110             for (ConstantPool.CPInfo cpinfo: cf.constant_pool.entries()) {
111                 if (cpinfo.getTag() == ConstantPool.CONSTANT_Methodref) {
112                     CONSTANT_Methodref_info ref = (CONSTANT_Methodref_info) cpinfo;
113                     String methodDesc = ref.getClassInfo().getName() + "." + ref.getNameAndTypeInfo().getName() + ":" + ref.getNameAndTypeInfo().getType();
114 
115                     if ("java/lang/String.toLowerCase:()Ljava/lang/String;".equals(methodDesc)) {
116                         error("found reference to String.toLowerCase() in: " + fo.getName());
117                     }
118                     if ("java/lang/String.toUpperCase:()Ljava/lang/String;".equals(methodDesc)) {
119                         error("found reference to String.toLowerCase() in: " + fo.getName());
120                     }
121                 }
122             }
123         } catch (ConstantPoolException ignore) {
124         } finally {
125             in.close();
126         }
127     }
128 
129     /**
130      * Report an error.
131      */
error(String msg)132     void error(String msg) {
133         System.err.println("Error: " + msg);
134         errors++;
135     }
136 
137     int errors;
138 }
139