1 /*
2 * Copyright (c) 2008, 2011, 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 sun.nio.fs;
27
28 import java.nio.file.*;
29 import java.nio.file.attribute.*;
30 import java.nio.channels.*;
31 import java.util.*;
32 import java.io.IOException;
33 import java.security.AccessController;
34 import java.security.PrivilegedAction;
35
36 /**
37 * Base implementation of FileStore for Unix/like implementations.
38 */
39
40 abstract class UnixFileStore
41 extends FileStore
42 {
43 // original path of file that identified file system
44 private final UnixPath file;
45
46 // device ID
47 private final long dev;
48
49 // entry in the mount tab
50 private final UnixMountEntry entry;
51
52 // return the device ID where the given file resides
53 private static long devFor(UnixPath file) throws IOException {
54 try {
55 return UnixFileAttributes.get(file, true).dev();
56 } catch (UnixException x) {
57 x.rethrowAsIOException(file);
58 return 0L; // keep compiler happy
59 }
60 }
61
62 UnixFileStore(UnixPath file) throws IOException {
63 this.file = file;
64 this.dev = devFor(file);
65 this.entry = findMountEntry();
66 }
67
68 UnixFileStore(UnixFileSystem fs, UnixMountEntry entry) throws IOException {
69 this.file = new UnixPath(fs, entry.dir());
70 this.dev = (entry.dev() == 0L) ? devFor(this.file) : entry.dev();
71 this.entry = entry;
72 }
73
74 /**
75 * Find the mount entry for the file store
76 */
77 abstract UnixMountEntry findMountEntry() throws IOException;
78
79 UnixPath file() {
80 return file;
81 }
82
83 long dev() {
84 return dev;
85 }
86
87 UnixMountEntry entry() {
88 return entry;
89 }
90
91 @Override
92 public String name() {
93 return entry.name();
94 }
95
96 @Override
97 public String type() {
98 return entry.fstype();
99 }
100
101 @Override
102 public boolean isReadOnly() {
103 return entry.isReadOnly();
104 }
105
106 // uses statvfs to read the file system information
107 private UnixFileStoreAttributes readAttributes() throws IOException {
108 try {
109 return UnixFileStoreAttributes.get(file);
110 } catch (UnixException x) {
111 x.rethrowAsIOException(file);
112 return null; // keep compile happy
113 }
114 }
115
116 @Override
117 public long getTotalSpace() throws IOException {
118 UnixFileStoreAttributes attrs = readAttributes();
119 return attrs.blockSize() * attrs.totalBlocks();
120 }
121
122 @Override
123 public long getUsableSpace() throws IOException {
124 UnixFileStoreAttributes attrs = readAttributes();
125 return attrs.blockSize() * attrs.availableBlocks();
126 }
127
128 @Override
129 public long getUnallocatedSpace() throws IOException {
130 UnixFileStoreAttributes attrs = readAttributes();
131 return attrs.blockSize() * attrs.freeBlocks();
132 }
133
134 @Override
135 public <V extends FileStoreAttributeView> V getFileStoreAttributeView(Class<V> view)
136 {
137 if (view == null)
138 throw new NullPointerException();
139 return (V) null;
140 }
141
142 @Override
143 public Object getAttribute(String attribute) throws IOException {
144 if (attribute.equals("totalSpace"))
145 return getTotalSpace();
146 if (attribute.equals("usableSpace"))
147 return getUsableSpace();
148 if (attribute.equals("unallocatedSpace"))
149 return getUnallocatedSpace();
150 throw new UnsupportedOperationException("'" + attribute + "' not recognized");
151 }
152
153 @Override
154 public boolean supportsFileAttributeView(Class<? extends FileAttributeView> type) {
155 if (type == null)
156 throw new NullPointerException();
157 if (type == BasicFileAttributeView.class)
158 return true;
159 if (type == PosixFileAttributeView.class ||
160 type == FileOwnerAttributeView.class)
161 {
162 // lookup fstypes.properties
163 FeatureStatus status = checkIfFeaturePresent("posix");
164 // assume supported if UNKNOWN
165 return (status != FeatureStatus.NOT_PRESENT);
166 }
167 return false;
168 }
169
170 @Override
171 public boolean supportsFileAttributeView(String name) {
172 if (name.equals("basic") || name.equals("unix"))
173 return true;
174 if (name.equals("posix"))
175 return supportsFileAttributeView(PosixFileAttributeView.class);
176 if (name.equals("owner"))
177 return supportsFileAttributeView(FileOwnerAttributeView.class);
178 return false;
179 }
180
181 @Override
182 public boolean equals(Object ob) {
183 if (ob == this)
184 return true;
185 if (!(ob instanceof UnixFileStore))
186 return false;
187 UnixFileStore other = (UnixFileStore)ob;
188 return (this.dev == other.dev) &&
189 Arrays.equals(this.entry.dir(), other.entry.dir());
190 }
191
192 @Override
193 public int hashCode() {
194 return (int)(dev ^ (dev >>> 32)) ^ Arrays.hashCode(entry.dir());
195 }
196
197 @Override
198 public String toString() {
199 StringBuilder sb = new StringBuilder(new String(entry.dir()));
200 sb.append(" (");
201 sb.append(entry.name());
202 sb.append(")");
203 return sb.toString();
204 }
205
206 // -- fstypes.properties --
207
208 private static final Object loadLock = new Object();
209 private static volatile Properties props;
210
211 enum FeatureStatus {
212 PRESENT,
213 NOT_PRESENT,
214 UNKNOWN;
215 }
216
217 /**
218 * Returns status to indicate if file system supports a given feature
219 */
220 FeatureStatus checkIfFeaturePresent(String feature) {
221 if (props == null) {
222 synchronized (loadLock) {
223 if (props == null) {
224 props = AccessController.doPrivileged(
225 new PrivilegedAction<Properties>() {
226 @Override
227 public Properties run() {
228 return loadProperties();
229 }});
230 }
231 }
232 }
233
234 String value = props.getProperty(type());
235 if (value != null) {
236 String[] values = value.split("\\s");
237 for (String s: values) {
238 s = s.trim().toLowerCase();
239 if (s.equals(feature)) {
240 return FeatureStatus.PRESENT;
241 }
242 if (s.startsWith("no")) {
243 s = s.substring(2);
244 if (s.equals(feature)) {
245 return FeatureStatus.NOT_PRESENT;
246 }
247 }
248 }
249 }
250 return FeatureStatus.UNKNOWN;
251 }
252
253 private static Properties loadProperties() {
254 Properties result = new Properties();
255 String fstypes = System.getProperty("java.home") + "/lib/fstypes.properties";
256 Path file = Paths.get(fstypes);
257 try {
258 try (ReadableByteChannel rbc = Files.newByteChannel(file)) {
259 result.load(Channels.newReader(rbc, "UTF-8"));
260 }
261 } catch (IOException x) {
262 }
263 return result;
264 }
265 }