1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache license, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the license for the specific language governing permissions and
15 * limitations under the license.
16 */
17 package org.apache.logging.log4j.core.appender;
18
19 import java.io.BufferedOutputStream;
20 import java.io.File;
21 import java.io.FileNotFoundException;
22 import java.io.FileOutputStream;
23 import java.io.IOException;
24 import java.io.OutputStream;
25 import java.io.Serializable;
26 import java.nio.channels.FileChannel;
27 import java.nio.channels.FileLock;
28 import java.util.HashMap;
29 import java.util.Map;
30
31 import org.apache.logging.log4j.core.Layout;
32
33
34 /**
35 * Manages actual File I/O for File Appenders.
36 */
37 public class FileManager extends OutputStreamManager {
38
39 private static final FileManagerFactory FACTORY = new FileManagerFactory();
40
41 private final boolean isAppend;
42 private final boolean isLocking;
43 private final String advertiseURI;
44 private final int bufferSize;
45
46 protected FileManager(final String fileName, final OutputStream os, final boolean append, final boolean locking,
47 final String advertiseURI, final Layout<? extends Serializable> layout, final int bufferSize,
48 final boolean writeHeader) {
49 super(os, fileName, layout, writeHeader);
50 this.isAppend = append;
51 this.isLocking = locking;
52 this.advertiseURI = advertiseURI;
53 this.bufferSize = bufferSize;
54 }
55
56 /**
57 * Returns the FileManager.
58 * @param fileName The name of the file to manage.
59 * @param append true if the file should be appended to, false if it should be overwritten.
60 * @param locking true if the file should be locked while writing, false otherwise.
61 * @param bufferedIo true if the contents should be buffered as they are written.
62 * @param advertiseUri the URI to use when advertising the file
63 * @param layout The layout
64 * @param bufferSize buffer size for buffered IO
65 * @return A FileManager for the File.
66 */
67 public static FileManager getFileManager(final String fileName, final boolean append, boolean locking,
68 final boolean bufferedIo, final String advertiseUri, final Layout<? extends Serializable> layout,
69 final int bufferSize) {
70
71 if (locking && bufferedIo) {
72 locking = false;
73 }
74 return (FileManager) getManager(fileName, new FactoryData(append, locking, bufferedIo, bufferSize,
75 advertiseUri, layout), FACTORY);
76 }
77
78 @Override
79 protected synchronized void write(final byte[] bytes, final int offset, final int length) {
80
81 if (isLocking) {
82 final FileChannel channel = ((FileOutputStream) getOutputStream()).getChannel();
83 try {
84 /* Lock the whole file. This could be optimized to only lock from the current file
85 position. Note that locking may be advisory on some systems and mandatory on others,
86 so locking just from the current position would allow reading on systems where
87 locking is mandatory. Also, Java 6 will throw an exception if the region of the
88 file is already locked by another FileChannel in the same JVM. Hopefully, that will
89 be avoided since every file should have a single file manager - unless two different
90 files strings are configured that somehow map to the same file.*/
91 final FileLock lock = channel.lock(0, Long.MAX_VALUE, false);
92 try {
93 super.write(bytes, offset, length);
94 } finally {
95 lock.release();
96 }
97 } catch (final IOException ex) {
98 throw new AppenderLoggingException("Unable to obtain lock on " + getName(), ex);
99 }
100
101 } else {
102 super.write(bytes, offset, length);
103 }
104 }
105
106 /**
107 * Returns the name of the File being managed.
108 * @return The name of the File being managed.
109 */
110 public String getFileName() {
111 return getName();
112 }
113
114 /**
115 * Returns the append status.
116 * @return true if the file will be appended to, false if it is overwritten.
117 */
118 public boolean isAppend() {
119 return isAppend;
120 }
121
122 /**
123 * Returns the lock status.
124 * @return true if the file will be locked when writing, false otherwise.
125 */
126 public boolean isLocking() {
127 return isLocking;
128 }
129
130 /**
131 * Returns the buffer size to use if the appender was configured with BufferedIO=true, otherwise returns a negative
132 * number.
133 * @return the buffer size, or a negative number if the output stream is not buffered
134 */
135 public int getBufferSize() {
136 return bufferSize;
137 }
138
139 /**
140 * FileManager's content format is specified by: <code>Key: "fileURI" Value: provided "advertiseURI" param</code>.
141 *
142 * @return Map of content format keys supporting FileManager
143 */
144 @Override
145 public Map<String, String> getContentFormat() {
146 final Map<String, String> result = new HashMap<>(super.getContentFormat());
147 result.put("fileURI", advertiseURI);
148 return result;
149 }
150
151 /**
152 * Factory Data.
153 */
154 private static class FactoryData {
155 private final boolean append;
156 private final boolean locking;
157 private final boolean bufferedIO;
158 private final int bufferSize;
159 private final String advertiseURI;
160 private final Layout<? extends Serializable> layout;
161
162 /**
163 * Constructor.
164 * @param append Append status.
165 * @param locking Locking status.
166 * @param bufferedIO Buffering flag.
167 * @param bufferSize Buffer size.
168 * @param advertiseURI the URI to use when advertising the file
169 */
170 public FactoryData(final boolean append, final boolean locking, final boolean bufferedIO, final int bufferSize,
171 final String advertiseURI, final Layout<? extends Serializable> layout) {
172 this.append = append;
173 this.locking = locking;
174 this.bufferedIO = bufferedIO;
175 this.bufferSize = bufferSize;
176 this.advertiseURI = advertiseURI;
177 this.layout = layout;
178 }
179 }
180
181 /**
182 * Factory to create a FileManager.
183 */
184 private static class FileManagerFactory implements ManagerFactory<FileManager, FactoryData> {
185
186 /**
187 * Create a FileManager.
188 * @param name The name of the File.
189 * @param data The FactoryData
190 * @return The FileManager for the File.
191 */
192 @Override
193 public FileManager createManager(final String name, final FactoryData data) {
194 final File file = new File(name);
195 final File parent = file.getParentFile();
196 if (null != parent && !parent.exists()) {
197 parent.mkdirs();
198 }
199
200 final boolean writeHeader = !data.append || !file.exists();
201 OutputStream os;
202 try {
203 os = new FileOutputStream(name, data.append);
204 int bufferSize = data.bufferSize;
205 if (data.bufferedIO) {
206 os = new BufferedOutputStream(os, bufferSize);
207 } else {
208 bufferSize = -1; // signals to RollingFileManager not to use BufferedOutputStream
209 }
210 return new FileManager(name, os, data.append, data.locking, data.advertiseURI, data.layout, bufferSize,
211 writeHeader);
212 } catch (final FileNotFoundException ex) {
213 LOGGER.error("FileManager (" + name + ") " + ex, ex);
214 }
215 return null;
216 }
217 }
218
219 }