-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathTempFileHelper.java
More file actions
175 lines (161 loc) · 5.93 KB
/
TempFileHelper.java
File metadata and controls
175 lines (161 loc) · 5.93 KB
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
/*
* Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
package java.nio.file;
import java.util.Set;
import java.util.EnumSet;
import java.security.SecureRandom;
import static java.security.AccessController.*;
import java.io.IOException;
import java.nio.file.attribute.FileAttribute;
import java.nio.file.attribute.PosixFilePermission;
import java.nio.file.attribute.PosixFilePermissions;
import static java.nio.file.attribute.PosixFilePermission.*;
import sun.security.action.GetPropertyAction;
/**
* Helper class to support creation of temporary files and directories with
* initial attributes.
*/
class TempFileHelper {
private TempFileHelper() { }
// temporary directory location
private static final Path tmpdir =
Paths.get(doPrivileged(new GetPropertyAction("java.io.tmpdir")));
private static final boolean isPosix =
FileSystems.getDefault().supportedFileAttributeViews().contains("posix");
// file name generation, same as java.io.File for now
private static final SecureRandom random = new SecureRandom();
private static Path generatePath(String prefix, String suffix, Path dir) {
long n = random.nextLong();
n = (n == Long.MIN_VALUE) ? 0 : Math.abs(n);
Path name = dir.getFileSystem().getPath(prefix + Long.toString(n) + suffix);
// the generated name should be a simple file name
if (name.getParent() != null)
throw new IllegalArgumentException("Invalid prefix or suffix");
return dir.resolve(name);
}
// default file and directory permissions (lazily initialized)
private static class PosixPermissions {
static final FileAttribute<Set<PosixFilePermission>> filePermissions =
PosixFilePermissions.asFileAttribute(EnumSet.of(OWNER_READ, OWNER_WRITE));
static final FileAttribute<Set<PosixFilePermission>> dirPermissions =
PosixFilePermissions.asFileAttribute(EnumSet
.of(OWNER_READ, OWNER_WRITE, OWNER_EXECUTE));
}
/**
* Creates a file or directory in in the given given directory (or in the
* temporary directory if dir is {@code null}).
*/
private static Path create(Path dir,
String prefix,
String suffix,
boolean createDirectory,
FileAttribute<?>[] attrs)
throws IOException
{
if (prefix == null)
prefix = "";
if (suffix == null)
suffix = (createDirectory) ? "" : ".tmp";
if (dir == null)
dir = tmpdir;
// in POSIX environments use default file and directory permissions
// if initial permissions not given by caller.
if (isPosix && (dir.getFileSystem() == FileSystems.getDefault())) {
if (attrs.length == 0) {
// no attributes so use default permissions
attrs = new FileAttribute<?>[1];
attrs[0] = (createDirectory) ? PosixPermissions.dirPermissions :
PosixPermissions.filePermissions;
} else {
// check if posix permissions given; if not use default
boolean hasPermissions = false;
for (int i=0; i<attrs.length; i++) {
if (attrs[i].name().equals("posix:permissions")) {
hasPermissions = true;
break;
}
}
if (!hasPermissions) {
FileAttribute<?>[] copy = new FileAttribute<?>[attrs.length+1];
System.arraycopy(attrs, 0, copy, 0, attrs.length);
attrs = copy;
attrs[attrs.length-1] = (createDirectory) ?
PosixPermissions.dirPermissions :
PosixPermissions.filePermissions;
}
}
}
// loop generating random names until file or directory can be created
SecurityManager sm = System.getSecurityManager();
for (;;) {
Path f;
try {
f = generatePath(prefix, suffix, dir);
} catch (InvalidPathException e) {
// don't reveal temporary directory location
if (sm != null)
throw new IllegalArgumentException("Invalid prefix or suffix");
throw e;
}
try {
if (createDirectory) {
return Files.createDirectory(f, attrs);
} else {
return Files.createFile(f, attrs);
}
} catch (SecurityException e) {
// don't reveal temporary directory location
if (dir == tmpdir && sm != null)
throw new SecurityException("Unable to create temporary file or directory");
throw e;
} catch (FileAlreadyExistsException e) {
// ignore
}
}
}
/**
* Creates a temporary file in the given directory, or in in the
* temporary directory if dir is {@code null}.
*/
static Path createTempFile(Path dir,
String prefix,
String suffix,
FileAttribute<?>[] attrs)
throws IOException
{
return create(dir, prefix, suffix, false, attrs);
}
/**
* Creates a temporary directory in the given directory, or in in the
* temporary directory if dir is {@code null}.
*/
static Path createTempDirectory(Path dir,
String prefix,
FileAttribute<?>[] attrs)
throws IOException
{
return create(dir, prefix, null, true, attrs);
}
}