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.commons.io;
18
19 import java.io.BufferedReader;
20 import java.io.IOException;
21 import java.io.InputStream;
22 import java.io.InputStreamReader;
23 import java.io.OutputStream;
24 import java.util.ArrayList;
25 import java.util.Arrays;
26 import java.util.List;
27 import java.util.StringTokenizer;
28
29 /**
30 * General File System utilities.
31 * <p>
32 * This class provides static utility methods for general file system
33 * functions not provided via the JDK {@link java.io.File File} class.
34 * <p>
35 * The current functions provided are:
36 * <ul>
37 * <li>Get the free space on a drive
38 * </ul>
39 *
40 * @author Frank W. Zammetti
41 * @author Stephen Colebourne
42 * @author Thomas Ledoux
43 * @author James Urie
44 * @author Magnus Grimsell
45 * @author Thomas Ledoux
46 * @version $Id: FileSystemUtils.java 453889 2006-10-07 11:56:25Z scolebourne $
47 * @since Commons IO 1.1
48 */
49 public class FileSystemUtils {
50
51 /** Singleton instance, used mainly for testing. */
52 private static final FileSystemUtils INSTANCE = new FileSystemUtils();
53
54 /** Operating system state flag for error. */
55 private static final int INIT_PROBLEM = -1;
56 /** Operating system state flag for neither Unix nor Windows. */
57 private static final int OTHER = 0;
58 /** Operating system state flag for Windows. */
59 private static final int WINDOWS = 1;
60 /** Operating system state flag for Unix. */
61 private static final int UNIX = 2;
62 /** Operating system state flag for Posix flavour Unix. */
63 private static final int POSIX_UNIX = 3;
64
65 /** The operating system flag. */
66 private static final int OS;
67 static {
68 int os = OTHER;
69 try {
70 String osName = System.getProperty("os.name");
71 if (osName == null) {
72 throw new IOException("os.name not found");
73 }
74 osName = osName.toLowerCase();
75 // match
76 if (osName.indexOf("windows") != -1) {
77 os = WINDOWS;
78 } else if (osName.indexOf("linux") != -1 ||
79 osName.indexOf("sun os") != -1 ||
80 osName.indexOf("sunos") != -1 ||
81 osName.indexOf("solaris") != -1 ||
82 osName.indexOf("mpe/ix") != -1 ||
83 osName.indexOf("freebsd") != -1 ||
84 osName.indexOf("irix") != -1 ||
85 osName.indexOf("digital unix") != -1 ||
86 osName.indexOf("unix") != -1 ||
87 osName.indexOf("mac os x") != -1) {
88 os = UNIX;
89 } else if (osName.indexOf("hp-ux") != -1 ||
90 osName.indexOf("aix") != -1) {
91 os = POSIX_UNIX;
92 } else {
93 os = OTHER;
94 }
95
96 } catch (Exception ex) {
97 os = INIT_PROBLEM;
98 }
99 OS = os;
100 }
101
102 /**
103 * Instances should NOT be constructed in standard programming.
104 */
105 public FileSystemUtils() {
106 super();
107 }
108
109 //-----------------------------------------------------------------------
110 /**
111 * Returns the free space on a drive or volume by invoking
112 * the command line.
113 * This method does not normalize the result, and typically returns
114 * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
115 * As this is not very useful, this method is deprecated in favour
116 * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
117 * <p>
118 * Note that some OS's are NOT currently supported, including OS/390,
119 * OpenVMS and and SunOS 5. (SunOS is supported by <code>freeSpaceKb</code>.)
120 * <pre>
121 * FileSystemUtils.freeSpace("C:"); // Windows
122 * FileSystemUtils.freeSpace("/volume"); // *nix
123 * </pre>
124 * The free space is calculated via the command line.
125 * It uses 'dir /-c' on Windows and 'df' on *nix.
126 *
127 * @param path the path to get free space for, not null, not empty on Unix
128 * @return the amount of free drive space on the drive or volume
129 * @throws IllegalArgumentException if the path is invalid
130 * @throws IllegalStateException if an error occurred in initialisation
131 * @throws IOException if an error occurs when finding the free space
132 * @since Commons IO 1.1, enhanced OS support in 1.2 and 1.3
133 * @deprecated Use freeSpaceKb(String)
134 * Deprecated from 1.3, may be removed in 2.0
135 */
136 public static long freeSpace(String path) throws IOException {
137 return INSTANCE.freeSpaceOS(path, OS, false);
138 }
139
140 //-----------------------------------------------------------------------
141 /**
142 * Returns the free space on a drive or volume in kilobytes by invoking
143 * the command line.
144 * <pre>
145 * FileSystemUtils.freeSpaceKb("C:"); // Windows
146 * FileSystemUtils.freeSpaceKb("/volume"); // *nix
147 * </pre>
148 * The free space is calculated via the command line.
149 * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
150 * <p>
151 * In order to work, you must be running Windows, or have a implementation of
152 * Unix df that supports GNU format when passed -k (or -kP). If you are going
153 * to rely on this code, please check that it works on your OS by running
154 * some simple tests to compare the command line with the output from this class.
155 * If your operating system isn't supported, please raise a JIRA call detailing
156 * the exact result from df -k and as much other detail as possible, thanks.
157 *
158 * @param path the path to get free space for, not null, not empty on Unix
159 * @return the amount of free drive space on the drive or volume in kilobytes
160 * @throws IllegalArgumentException if the path is invalid
161 * @throws IllegalStateException if an error occurred in initialisation
162 * @throws IOException if an error occurs when finding the free space
163 * @since Commons IO 1.2, enhanced OS support in 1.3
164 */
165 public static long freeSpaceKb(String path) throws IOException {
166 return INSTANCE.freeSpaceOS(path, OS, true);
167 }
168
169 //-----------------------------------------------------------------------
170 /**
171 * Returns the free space on a drive or volume in a cross-platform manner.
172 * Note that some OS's are NOT currently supported, including OS/390.
173 * <pre>
174 * FileSystemUtils.freeSpace("C:"); // Windows
175 * FileSystemUtils.freeSpace("/volume"); // *nix
176 * </pre>
177 * The free space is calculated via the command line.
178 * It uses 'dir /-c' on Windows and 'df' on *nix.
179 *
180 * @param path the path to get free space for, not null, not empty on Unix
181 * @param os the operating system code
182 * @param kb whether to normalize to kilobytes
183 * @return the amount of free drive space on the drive or volume
184 * @throws IllegalArgumentException if the path is invalid
185 * @throws IllegalStateException if an error occurred in initialisation
186 * @throws IOException if an error occurs when finding the free space
187 */
188 long freeSpaceOS(String path, int os, boolean kb) throws IOException {
189 if (path == null) {
190 throw new IllegalArgumentException("Path must not be empty");
191 }
192 switch (os) {
193 case WINDOWS:
194 return (kb ? freeSpaceWindows(path) / 1024 : freeSpaceWindows(path));
195 case UNIX:
196 return freeSpaceUnix(path, kb, false);
197 case POSIX_UNIX:
198 return freeSpaceUnix(path, kb, true);
199 case OTHER:
200 throw new IllegalStateException("Unsupported operating system");
201 default:
202 throw new IllegalStateException(
203 "Exception caught when determining operating system");
204 }
205 }
206
207 //-----------------------------------------------------------------------
208 /**
209 * Find free space on the Windows platform using the 'dir' command.
210 *
211 * @param path the path to get free space for, including the colon
212 * @return the amount of free drive space on the drive
213 * @throws IOException if an error occurs
214 */
215 long freeSpaceWindows(String path) throws IOException {
216 path = FilenameUtils.normalize(path);
217 if (path.length() > 2 && path.charAt(1) == ':') {
218 path = path.substring(0, 2); // seems to make it work
219 }
220
221 // build and run the 'dir' command
222 String[] cmdAttribs = new String[] {"cmd.exe", "/C", "dir /-c " + path};
223
224 // read in the output of the command to an ArrayList
225 List lines = performCommand(cmdAttribs, Integer.MAX_VALUE);
226
227 // now iterate over the lines we just read and find the LAST
228 // non-empty line (the free space bytes should be in the last element
229 // of the ArrayList anyway, but this will ensure it works even if it's
230 // not, still assuming it is on the last non-blank line)
231 for (int i = lines.size() - 1; i >= 0; i--) {
232 String line = (String) lines.get(i);
233 if (line.length() > 0) {
234 return parseDir(line, path);
235 }
236 }
237 // all lines are blank
238 throw new IOException(
239 "Command line 'dir /-c' did not return any info " +
240 "for path '" + path + "'");
241 }
242
243 /**
244 * Parses the Windows dir response last line
245 *
246 * @param line the line to parse
247 * @param path the path that was sent
248 * @return the number of bytes
249 * @throws IOException if an error occurs
250 */
251 long parseDir(String line, String path) throws IOException {
252 // read from the end of the line to find the last numeric
253 // character on the line, then continue until we find the first
254 // non-numeric character, and everything between that and the last
255 // numeric character inclusive is our free space bytes count
256 int bytesStart = 0;
257 int bytesEnd = 0;
258 int j = line.length() - 1;
259 innerLoop1: while (j >= 0) {
260 char c = line.charAt(j);
261 if (Character.isDigit(c)) {
262 // found the last numeric character, this is the end of
263 // the free space bytes count
264 bytesEnd = j + 1;
265 break innerLoop1;
266 }
267 j--;
268 }
269 innerLoop2: while (j >= 0) {
270 char c = line.charAt(j);
271 if (!Character.isDigit(c) && c != ',' && c != '.') {
272 // found the next non-numeric character, this is the
273 // beginning of the free space bytes count
274 bytesStart = j + 1;
275 break innerLoop2;
276 }
277 j--;
278 }
279 if (j < 0) {
280 throw new IOException(
281 "Command line 'dir /-c' did not return valid info " +
282 "for path '" + path + "'");
283 }
284
285 // remove commas and dots in the bytes count
286 StringBuffer buf = new StringBuffer(line.substring(bytesStart, bytesEnd));
287 for (int k = 0; k < buf.length(); k++) {
288 if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
289 buf.deleteCharAt(k--);
290 }
291 }
292 return parseBytes(buf.toString(), path);
293 }
294
295 //-----------------------------------------------------------------------
296 /**
297 * Find free space on the *nix platform using the 'df' command.
298 *
299 * @param path the path to get free space for
300 * @param kb whether to normalize to kilobytes
301 * @param posix whether to use the posix standard format flag
302 * @return the amount of free drive space on the volume
303 * @throws IOException if an error occurs
304 */
305 long freeSpaceUnix(String path, boolean kb, boolean posix) throws IOException {
306 if (path.length() == 0) {
307 throw new IllegalArgumentException("Path must not be empty");
308 }
309 path = FilenameUtils.normalize(path);
310
311 // build and run the 'dir' command
312 String flags = "-";
313 if (kb) {
314 flags += "k";
315 }
316 if (posix) {
317 flags += "P";
318 }
319 String[] cmdAttribs =
320 (flags.length() > 1 ? new String[] {"df", flags, path} : new String[] {"df", path});
321
322 // perform the command, asking for up to 3 lines (header, interesting, overflow)
323 List lines = performCommand(cmdAttribs, 3);
324 if (lines.size() < 2) {
325 // unknown problem, throw exception
326 throw new IOException(
327 "Command line 'df' did not return info as expected " +
328 "for path '" + path + "'- response was " + lines);
329 }
330 String line2 = (String) lines.get(1); // the line we're interested in
331
332 // Now, we tokenize the string. The fourth element is what we want.
333 StringTokenizer tok = new StringTokenizer(line2, " ");
334 if (tok.countTokens() < 4) {
335 // could be long Filesystem, thus data on third line
336 if (tok.countTokens() == 1 && lines.size() >= 3) {
337 String line3 = (String) lines.get(2); // the line may be interested in
338 tok = new StringTokenizer(line3, " ");
339 } else {
340 throw new IOException(
341 "Command line 'df' did not return data as expected " +
342 "for path '" + path + "'- check path is valid");
343 }
344 } else {
345 tok.nextToken(); // Ignore Filesystem
346 }
347 tok.nextToken(); // Ignore 1K-blocks
348 tok.nextToken(); // Ignore Used
349 String freeSpace = tok.nextToken();
350 return parseBytes(freeSpace, path);
351 }
352
353 //-----------------------------------------------------------------------
354 /**
355 * Parses the bytes from a string.
356 *
357 * @param freeSpace the free space string
358 * @param path the path
359 * @return the number of bytes
360 * @throws IOException if an error occurs
361 */
362 long parseBytes(String freeSpace, String path) throws IOException {
363 try {
364 long bytes = Long.parseLong(freeSpace);
365 if (bytes < 0) {
366 throw new IOException(
367 "Command line 'df' did not find free space in response " +
368 "for path '" + path + "'- check path is valid");
369 }
370 return bytes;
371
372 } catch (NumberFormatException ex) {
373 throw new IOException(
374 "Command line 'df' did not return numeric data as expected " +
375 "for path '" + path + "'- check path is valid");
376 }
377 }
378
379 //-----------------------------------------------------------------------
380 /**
381 * Performs the os command.
382 *
383 * @param cmdAttribs the command line parameters
384 * @param max The maximum limit for the lines returned
385 * @return the parsed data
386 * @throws IOException if an error occurs
387 */
388 List performCommand(String[] cmdAttribs, int max) throws IOException {
389 // this method does what it can to avoid the 'Too many open files' error
390 // based on trial and error and these links:
391 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
392 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
393 // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
394 // however, its still not perfect as the JDK support is so poor
395 // (see commond-exec or ant for a better multi-threaded multi-os solution)
396
397 List lines = new ArrayList(20);
398 Process proc = null;
399 InputStream in = null;
400 OutputStream out = null;
401 InputStream err = null;
402 BufferedReader inr = null;
403 try {
404 proc = openProcess(cmdAttribs);
405 in = proc.getInputStream();
406 out = proc.getOutputStream();
407 err = proc.getErrorStream();
408 inr = new BufferedReader(new InputStreamReader(in));
409 String line = inr.readLine();
410 while (line != null && lines.size() < max) {
411 line = line.toLowerCase().trim();
412 lines.add(line);
413 line = inr.readLine();
414 }
415
416 proc.waitFor();
417 if (proc.exitValue() != 0) {
418 // os command problem, throw exception
419 throw new IOException(
420 "Command line returned OS error code '" + proc.exitValue() +
421 "' for command " + Arrays.asList(cmdAttribs));
422 }
423 if (lines.size() == 0) {
424 // unknown problem, throw exception
425 throw new IOException(
426 "Command line did not return any info " +
427 "for command " + Arrays.asList(cmdAttribs));
428 }
429 return lines;
430
431 } catch (InterruptedException ex) {
432 throw new IOException(
433 "Command line threw an InterruptedException '" + ex.getMessage() +
434 "' for command " + Arrays.asList(cmdAttribs));
435 } finally {
436 IOUtils.closeQuietly(in);
437 IOUtils.closeQuietly(out);
438 IOUtils.closeQuietly(err);
439 IOUtils.closeQuietly(inr);
440 if (proc != null) {
441 proc.destroy();
442 }
443 }
444 }
445
446 /**
447 * Opens the process to the operating system.
448 *
449 * @param cmdAttribs the command line parameters
450 * @return the process
451 * @throws IOException if an error occurs
452 */
453 Process openProcess(String[] cmdAttribs) throws IOException {
454 return Runtime.getRuntime().exec(cmdAttribs);
455 }
456
457 }