1 /*
2 * Copyright (c) 2014, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.internal.jrtfs;
27
28 import java.util.regex.PatternSyntaxException;
29
30 final class JrtUtils {
31 private JrtUtils() {}
32
33 private static final String regexMetaChars = ".^$+{[]|()";
34 private static final String globMetaChars = "\\*?[{";
35 private static boolean isRegexMeta(char c) {
36 return regexMetaChars.indexOf(c) != -1;
37 }
38 private static boolean isGlobMeta(char c) {
39 return globMetaChars.indexOf(c) != -1;
40 }
41 private static final char EOL = 0; //TBD
42 private static char next(String glob, int i) {
43 if (i < glob.length()) {
44 return glob.charAt(i);
45 }
46 return EOL;
47 }
48
49 /*
50 * Creates a regex pattern from the given glob expression.
51 *
52 * @throws PatternSyntaxException
53 */
54 public static String toRegexPattern(String globPattern) {
55 boolean inGroup = false;
56 StringBuilder regex = new StringBuilder("^");
57
58 int i = 0;
59 while (i < globPattern.length()) {
60 char c = globPattern.charAt(i++);
61 switch (c) {
62 case '\\':
63 // escape special characters
64 if (i == globPattern.length()) {
65 throw new PatternSyntaxException("No character to escape",
66 globPattern, i - 1);
67 }
68 char next = globPattern.charAt(i++);
69 if (isGlobMeta(next) || isRegexMeta(next)) {
70 regex.append('\\');
71 }
72 regex.append(next);
73 break;
74 case '/':
75 regex.append(c);
76 break;
77 case '[':
78 // don't match name separator in class
79 regex.append("[[^/]&&[");
80 if (next(globPattern, i) == '^') {
81 // escape the regex negation char if it appears
82 regex.append("\\^");
83 i++;
84 } else {
85 // negation
86 if (next(globPattern, i) == '!') {
87 regex.append('^');
88 i++;
89 }
90 // hyphen allowed at start
91 if (next(globPattern, i) == '-') {
92 regex.append('-');
93 i++;
94 }
95 }
96 boolean hasRangeStart = false;
97 char last = 0;
98 while (i < globPattern.length()) {
99 c = globPattern.charAt(i++);
100 if (c == ']') {
101 break;
102 }
103 if (c == '/') {
104 throw new PatternSyntaxException("Explicit 'name separator' in class",
105 globPattern, i - 1);
106 }
107 // TBD: how to specify ']' in a class?
108 if (c == '\\' || c == '[' ||
109 c == '&' && next(globPattern, i) == '&') {
110 // escape '\', '[' or "&&" for regex class
111 regex.append('\\');
112 }
113 regex.append(c);
114
115 if (c == '-') {
116 if (!hasRangeStart) {
117 throw new PatternSyntaxException("Invalid range",
118 globPattern, i - 1);
119 }
120 if ((c = next(globPattern, i++)) == EOL || c == ']') {
121 break;
122 }
123 if (c < last) {
124 throw new PatternSyntaxException("Invalid range",
125 globPattern, i - 3);
126 }
127 regex.append(c);
128 hasRangeStart = false;
129 } else {
130 hasRangeStart = true;
131 last = c;
132 }
133 }
134 if (c != ']') {
135 throw new PatternSyntaxException("Missing ']", globPattern, i - 1);
136 }
137 regex.append("]]");
138 break;
139 case '{':
140 if (inGroup) {
141 throw new PatternSyntaxException("Cannot nest groups",
142 globPattern, i - 1);
143 }
144 regex.append("(?:(?:");
145 inGroup = true;
146 break;
147 case '}':
148 if (inGroup) {
149 regex.append("))");
150 inGroup = false;
151 } else {
152 regex.append('}');
153 }
154 break;
155 case ',':
156 if (inGroup) {
157 regex.append(")|(?:");
158 } else {
159 regex.append(',');
160 }
161 break;
162 case '*':
163 if (next(globPattern, i) == '*') {
164 // crosses directory boundaries
165 regex.append(".*");
166 i++;
167 } else {
168 // within directory boundary
169 regex.append("[^/]*");
170 }
171 break;
172 case '?':
173 regex.append("[^/]");
174 break;
175 default:
176 if (isRegexMeta(c)) {
177 regex.append('\\');
178 }
179 regex.append(c);
180 }
181 }
182 if (inGroup) {
183 throw new PatternSyntaxException("Missing '}", globPattern, i - 1);
184 }
185 return regex.append('$').toString();
186 }
187 }