| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * This file is available under and governed by the GNU General Public |
| * License version 2 only, as published by the Free Software Foundation. |
| * However, the following notice accompanied the original version of this |
| * file, and Oracle licenses the original version of this file under the BSD |
| * license: |
| */ |
| /* |
| Copyright 2009-2013 Attila Szegedi |
| |
| Licensed under both the Apache License, Version 2.0 (the "Apache License") |
| and the BSD License (the "BSD License"), with licensee being free to |
| choose either of the two at their discretion. |
| |
| You may not use this file except in compliance with either the Apache |
| License or the BSD License. |
| |
| If you choose to use this file in compliance with the Apache License, the |
| following notice applies to you: |
| |
| You may obtain a copy of the Apache License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or |
| implied. See the License for the specific language governing |
| permissions and limitations under the License. |
| |
| If you choose to use this file in compliance with the BSD License, the |
| following notice applies to you: |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are |
| met: |
| * Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| * Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| * Neither the name of the copyright holder nor the names of |
| contributors may be used to endorse or promote products derived from |
| this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
| IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
| PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER |
| BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| package jdk.internal.dynalink.support; |
| |
| import jdk.internal.dynalink.CallSiteDescriptor; |
| |
| /** |
| * Implements the name mangling and demangling as specified by John Rose's |
| * <a href="https://blogs.oracle.com/jrose/entry/symbolic_freedom_in_the_vm" target="_blank">"Symbolic Freedom in the |
| * VM"</a> article. It is recommended that implementers of languages on the JVM uniformly adopt this for symbolic |
| * interoperability between languages. Normally, you would mangle the names as you're generating bytecode, and then |
| * demangle them when you're creating {@link CallSiteDescriptor} objects. Note that you are expected to mangle |
| * individual tokens, and not the whole name at the call site, i.e. the colon character normally separating the tokens |
| * is never mangled. I.e. you wouldn't mangle {@code dyn:getProp:color} into {@code dyn\!getProp\!color}, but you would |
| * mangle {@code dyn:getProp:color$} into {@code dyn:getProp:\=color\%} (only mangling the individual token containing |
| * the symbol {@code color$}). {@link CallSiteDescriptorFactory#tokenizeName(String)} (and by implication, all call site |
| * descriptors it creates) will automatically perform demangling on the passed names. If you use this factory, or you |
| * have your own way of creating call site descriptors, but you still delegate to this method of the default factory |
| * (it is recommended that you do), then you have demangling handled for you already, and only need to ensure that you |
| * mangle the names when you're emitting them in the bytecode. |
| * |
| * @author Attila Szegedi |
| */ |
| public class NameCodec { |
| private static final char ESCAPE_CHAR = '\\'; |
| private static final char EMPTY_ESCAPE = '='; |
| private static final String EMPTY_NAME = new String(new char[] { ESCAPE_CHAR, EMPTY_ESCAPE }); |
| private static final char EMPTY_CHAR = 0xFEFF; |
| |
| private static final int MIN_ENCODING = '$'; |
| private static final int MAX_ENCODING = ']'; |
| private static final char[] ENCODING = new char[MAX_ENCODING - MIN_ENCODING + 1]; |
| private static final int MIN_DECODING = '!'; |
| private static final int MAX_DECODING = '}'; |
| private static final char[] DECODING = new char[MAX_DECODING - MIN_DECODING + 1]; |
| |
| static { |
| addEncoding('/', '|'); |
| addEncoding('.', ','); |
| addEncoding(';', '?'); |
| addEncoding('$', '%'); |
| addEncoding('<', '^'); |
| addEncoding('>', '_'); |
| addEncoding('[', '{'); |
| addEncoding(']', '}'); |
| addEncoding(':', '!'); |
| addEncoding('\\', '-'); |
| DECODING[EMPTY_ESCAPE - MIN_DECODING] = EMPTY_CHAR; |
| } |
| |
| private NameCodec() { |
| } |
| |
| /** |
| * Encodes ("mangles") an unencoded symbolic name. |
| * @param name the symbolic name to mangle |
| * @return the mangled form of the symbolic name. |
| */ |
| public static String encode(final String name) { |
| final int l = name.length(); |
| if(l == 0) { |
| return EMPTY_NAME; |
| } |
| StringBuilder b = null; |
| int lastEscape = -1; |
| for(int i = 0; i < l; ++i) { |
| final int encodeIndex = name.charAt(i) - MIN_ENCODING; |
| if(encodeIndex >= 0 && encodeIndex < ENCODING.length) { |
| final char e = ENCODING[encodeIndex]; |
| if(e != 0) { |
| if(b == null) { |
| b = new StringBuilder(name.length() + 3); |
| if(name.charAt(0) != ESCAPE_CHAR && i > 0) { |
| b.append(EMPTY_NAME); |
| } |
| b.append(name, 0, i); |
| } else { |
| b.append(name, lastEscape + 1, i); |
| } |
| b.append(ESCAPE_CHAR).append(e); |
| lastEscape = i; |
| } |
| } |
| } |
| if(b == null) { |
| return name.toString(); |
| } |
| assert lastEscape != -1; |
| b.append(name, lastEscape + 1, l); |
| return b.toString(); |
| } |
| |
| /** |
| * Decodes ("demangles") an encoded symbolic name. |
| * @param name the symbolic name to demangle |
| * @return the demangled form of the symbolic name. |
| */ |
| public static String decode(final String name) { |
| if(name.charAt(0) != ESCAPE_CHAR) { |
| return name; |
| } |
| final int l = name.length(); |
| if(l == 2 && name.charAt(1) == EMPTY_CHAR) { |
| return ""; |
| } |
| final StringBuilder b = new StringBuilder(name.length()); |
| int lastEscape = -2; |
| int lastBackslash = -1; |
| for(;;) { |
| final int nextBackslash = name.indexOf(ESCAPE_CHAR, lastBackslash + 1); |
| if(nextBackslash == -1 || nextBackslash == l - 1) { |
| break; |
| } |
| final int decodeIndex = name.charAt(nextBackslash + 1) - MIN_DECODING; |
| if(decodeIndex >= 0 && decodeIndex < DECODING.length) { |
| final char d = DECODING[decodeIndex]; |
| if(d == EMPTY_CHAR) { |
| // "\=" is only valid at the beginning of a mangled string |
| if(nextBackslash == 0) { |
| lastEscape = 0; |
| } |
| } else if(d != 0) { |
| b.append(name, lastEscape + 2, nextBackslash).append(d); |
| lastEscape = nextBackslash; |
| } |
| } |
| lastBackslash = nextBackslash; |
| } |
| b.append(name, lastEscape + 2, l); |
| return b.toString(); |
| } |
| |
| private static void addEncoding(final char from, final char to) { |
| ENCODING[from - MIN_ENCODING] = to; |
| DECODING[to - MIN_DECODING] = from; |
| } |
| } |
