1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
|
/*
* Copyright (c) 2008, 2011, 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.
*/
package sun.nio.fs;
import java.nio.file.*;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.io.IOException;
import static sun.nio.fs.WindowsNativeDispatcher.*;
import static sun.nio.fs.WindowsConstants.*;
/**
* Windows implementation of DirectoryStream
*/
class WindowsDirectoryStream
implements DirectoryStream<Path>
{
private static final int NATIVE_BUFFER_SIZE = 8192;
private final WindowsPath dir;
private final DirectoryStream.Filter<? super Path> filter;
// Query directory information data structure
private final QueryDirectoryInformation queryDirectoryInformation;
// Buffer used to receive file entries from NtQueryDirectoryInformation calls
private final NativeBuffer queryDirectoryInformationBuffer;
private final Object closeLock = new Object();
// need closeLock to access these
private boolean isOpen = true;
private Iterator<Path> iterator;
WindowsDirectoryStream(WindowsPath dir, DirectoryStream.Filter<? super Path> filter)
throws IOException
{
this.dir = dir;
this.filter = filter;
this.queryDirectoryInformationBuffer = NativeBuffers.getNativeBuffer(NATIVE_BUFFER_SIZE);
try {
// Open the directory for reading and read the first set of entries in the native buffer
String search = dir.getPathForWin32Calls();
this.queryDirectoryInformation = OpenNtQueryDirectoryInformation(search, this.queryDirectoryInformationBuffer);
} catch (WindowsException x) {
// Release the buffer, as this instance is not fully constructed
this.queryDirectoryInformationBuffer.release();
if (x.lastError() == ERROR_DIRECTORY) {
throw new NotDirectoryException(dir.getPathForExceptionMessage());
}
x.rethrowAsIOException(dir);
// keep compiler happy
throw new AssertionError();
}
}
@Override
public void close()
throws IOException
{
synchronized (closeLock) {
if (!isOpen)
return;
isOpen = false;
}
queryDirectoryInformationBuffer.release();
try {
CloseNtQueryDirectoryInformation(queryDirectoryInformation);
} catch (WindowsException x) {
x.rethrowAsIOException(dir);
}
}
@Override
public Iterator<Path> iterator() {
if (!isOpen) {
throw new IllegalStateException("Directory stream is closed");
}
synchronized (this) {
if (iterator != null)
throw new IllegalStateException("Iterator already obtained");
iterator = new WindowsDirectoryIterator();
return iterator;
}
}
private class WindowsDirectoryIterator implements Iterator<Path> {
private boolean atEof;
private Path nextEntry;
private String prefix;
private int nextOffset;
WindowsDirectoryIterator() {
atEof = false;
nextOffset = 0;
if (dir.needsSlashWhenResolving()) {
prefix = dir.toString() + "\\";
} else {
prefix = dir.toString();
}
}
// links to self and parent directories are ignored
private boolean isSelfOrParent(String name) {
return name.equals(".") || name.equals("..");
}
// applies filter and also ignores "." and ".."
private Path acceptEntry(String s, BasicFileAttributes attrs) {
Path entry = WindowsPath
.createFromNormalizedPath(dir.getFileSystem(), prefix + s, attrs);
try {
if (filter.accept(entry))
return entry;
} catch (IOException ioe) {
throw new DirectoryIteratorException(ioe);
}
return null;
}
// reads next directory entry
private Path readNextEntry() {
for (;;) {
String name;
WindowsFileAttributes attrs;
// synchronize on closeLock to prevent close while reading
synchronized (closeLock) {
// Fetch next set of entries if we don't have anything available in buffer
if (!isOpen) {
atEof = true;
return null;
}
if (nextOffset < 0) {
try {
atEof = !NextNtQueryDirectoryInformation(queryDirectoryInformation, queryDirectoryInformationBuffer);
} catch (WindowsException x) {
IOException ioe = x.asIOException(dir);
throw new DirectoryIteratorException(ioe);
}
if (atEof) {
return null;
}
nextOffset = 0;
}
long dirInformationAddress = queryDirectoryInformationBuffer.address() + nextOffset;
int nextEntryOffset = WindowsFileAttributes.getNextOffsetFromFileDirInformation(
queryDirectoryInformation, dirInformationAddress);
nextOffset = nextEntryOffset == 0 ? -1 : nextOffset + nextEntryOffset;
name = WindowsFileAttributes.getFileNameFromFileDirInformation(
queryDirectoryInformation, dirInformationAddress);
if (isSelfOrParent(name)) {
// Skip "." and ".."
continue;
}
attrs = WindowsFileAttributes.fromFileDirInformation(queryDirectoryInformation, dirInformationAddress);
}
// return entry if accepted by filter
Path entry = acceptEntry(name, attrs);
if (entry != null)
return entry;
}
}
@Override
public synchronized boolean hasNext() {
if (nextEntry == null && !atEof)
nextEntry = readNextEntry();
return nextEntry != null;
}
@Override
public synchronized Path next() {
Path result = null;
if (nextEntry == null && !atEof) {
result = readNextEntry();
} else {
result = nextEntry;
nextEntry = null;
}
if (result == null)
throw new NoSuchElementException();
return result;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
}
}
|
