1 /*
2 * Copyright (c) 2008, 2017, 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 getBlockSize() throws IOException {
130 UnixFileStoreAttributes attrs = readAttributes();
131 return attrs.blockSize();
132 }
133
134 @Override
135 public long getUnallocatedSpace() throws IOException {
136 UnixFileStoreAttributes attrs = readAttributes();
137 return attrs.blockSize() * attrs.freeBlocks();
138 }
139
140 @Override
141 public <V extends FileStoreAttributeView> V getFileStoreAttributeView(Class<V> view)
142 {
143 if (view == null)
144 throw new NullPointerException();
145 return (V) null;
146 }
147
148 @Override
149 public Object getAttribute(String attribute) throws IOException {
150 if (attribute.equals("totalSpace"))
151 return getTotalSpace();
152 if (attribute.equals("usableSpace"))
153 return getUsableSpace();
154 if (attribute.equals("unallocatedSpace"))
155 return getUnallocatedSpace();
156 throw new UnsupportedOperationException("'" + attribute + "' not recognized");
157 }
158
159 @Override
160 public boolean supportsFileAttributeView(Class<? extends FileAttributeView> type) {
161 if (type == null)
162 throw new NullPointerException();
163 if (type == BasicFileAttributeView.class)
164 return true;
165 if (type == PosixFileAttributeView.class ||
166 type == FileOwnerAttributeView.class)
167 {
168 // lookup fstypes.properties
169 FeatureStatus status = checkIfFeaturePresent("posix");
170 // assume supported if UNKNOWN
171 return (status != FeatureStatus.NOT_PRESENT);
172 }
173 return false;
174 }
175
176 @Override
177 public boolean supportsFileAttributeView(String name) {
178 if (name.equals("basic") || name.equals("unix"))
179 return true;
180 if (name.equals("posix"))
181 return supportsFileAttributeView(PosixFileAttributeView.class);
182 if (name.equals("owner"))
183 return supportsFileAttributeView(FileOwnerAttributeView.class);
184 return false;
185 }
186
187 @Override
188 public boolean equals(Object ob) {
189 if (ob == this)
190 return true;
191 if (!(ob instanceof UnixFileStore))
192 return false;
193 UnixFileStore other = (UnixFileStore)ob;
194 return (this.dev == other.dev) &&
195 Arrays.equals(this.entry.dir(), other.entry.dir()) &&
196 this.entry.name().equals(other.entry.name());
197 }
198
199 @Override
200 public int hashCode() {
201 return (int)(dev ^ (dev >>> 32)) ^ Arrays.hashCode(entry.dir());
202 }
203
204 @Override
205 public String toString() {
206 StringBuilder sb = new StringBuilder(Util.toString(entry.dir()));
207 sb.append(" (");
208 sb.append(entry.name());
209 sb.append(")");
210 return sb.toString();
211 }
212
213 // -- fstypes.properties --
214
215 private static final Object loadLock = new Object();
216 private static volatile Properties props;
217
218 enum FeatureStatus {
219 PRESENT,
220 NOT_PRESENT,
221 UNKNOWN;
222 }
223
224 /**
225 * Returns status to indicate if file system supports a given feature
226 */
227 FeatureStatus checkIfFeaturePresent(String feature) {
228 if (props == null) {
229 synchronized (loadLock) {
230 if (props == null) {
231 props = AccessController.doPrivileged(
232 new PrivilegedAction<>() {
233 @Override
234 public Properties run() {
235 return loadProperties();
236 }});
237 }
238 }
239 }
240
241 String value = props.getProperty(type());
242 if (value != null) {
243 String[] values = value.split("\\s");
244 for (String s: values) {
245 s = s.trim().toLowerCase();
246 if (s.equals(feature)) {
247 return FeatureStatus.PRESENT;
248 }
249 if (s.startsWith("no")) {
250 s = s.substring(2);
251 if (s.equals(feature)) {
252 return FeatureStatus.NOT_PRESENT;
253 }
254 }
255 }
256 }
257 return FeatureStatus.UNKNOWN;
258 }
259
260 private static Properties loadProperties() {
261 Properties result = new Properties();
262 String fstypes = System.getProperty("java.home") + "/lib/fstypes.properties";
263 Path file = Path.get(fstypes);
264 try {
265 try (ReadableByteChannel rbc = Files.newByteChannel(file)) {
266 result.load(Channels.newReader(rbc, "UTF-8"));
267 }
268 } catch (IOException x) {
269 }
270 return result;
271 }
272 }