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.File;
21 import java.io.IOException;
22 import java.io.InputStream;
23 import java.io.InputStreamReader;
24 import java.io.OutputStream;
25 import java.nio.charset.Charset;
26 import java.util.ArrayList;
27 import java.util.Arrays;
28 import java.util.List;
29 import java.util.Locale;
30 import java.util.StringTokenizer;
31
32 /**
33 * General File System utilities.
34 * <p>
35 * This class provides static utility methods for general file system
36 * functions not provided via the JDK {@link java.io.File File} class.
37 * <p>
38 * The current functions provided are:
39 * <ul>
40 * <li>Get the free space on a drive
41 * </ul>
42 *
43 * @version $Id: FileSystemUtils.java 1471767 2013-04-24 23:24:19Z sebb $
44 * @since 1.1
45 */
46 public class FileSystemUtils {
47
48 /** Singleton instance, used mainly for testing. */
49 private static final FileSystemUtils INSTANCE = new FileSystemUtils();
50
51 /** Operating system state flag for error. */
52 private static final int INIT_PROBLEM = -1;
53 /** Operating system state flag for neither Unix nor Windows. */
54 private static final int OTHER = 0;
55 /** Operating system state flag for Windows. */
56 private static final int WINDOWS = 1;
57 /** Operating system state flag for Unix. */
58 private static final int UNIX = 2;
59 /** Operating system state flag for Posix flavour Unix. */
60 private static final int POSIX_UNIX = 3;
61
62 /** The operating system flag. */
63 private static final int OS;
64
65 /** The path to df */
66 private static final String DF;
67
68 static {
69 int os = OTHER;
70 String dfPath = "df";
71 try {
72 String osName = System.getProperty("os.name");
73 if (osName == null) {
74 throw new IOException("os.name not found");
75 }
76 osName = osName.toLowerCase(Locale.ENGLISH);
77 // match
78 if (osName.indexOf("windows") != -1) {
79 os = WINDOWS;
80 } else if (osName.indexOf("linux") != -1 ||
81 osName.indexOf("mpe/ix") != -1 ||
82 osName.indexOf("freebsd") != -1 ||
83 osName.indexOf("irix") != -1 ||
84 osName.indexOf("digital unix") != -1 ||
85 osName.indexOf("unix") != -1 ||
86 osName.indexOf("mac os x") != -1) {
87 os = UNIX;
88 } else if (osName.indexOf("sun os") != -1 ||
89 osName.indexOf("sunos") != -1 ||
90 osName.indexOf("solaris") != -1) {
91 os = POSIX_UNIX;
92 dfPath = "/usr/xpg4/bin/df";
93 } else if (osName.indexOf("hp-ux") != -1 ||
94 osName.indexOf("aix") != -1) {
95 os = POSIX_UNIX;
96 } else {
97 os = OTHER;
98 }
99
100 } catch (final Exception ex) {
101 os = INIT_PROBLEM;
102 }
103 OS = os;
104 DF = dfPath;
105 }
106
107 /**
108 * Instances should NOT be constructed in standard programming.
109 */
110 public FileSystemUtils() {
111 super();
112 }
113
114 //-----------------------------------------------------------------------
115 /**
116 * Returns the free space on a drive or volume by invoking
117 * the command line.
118 * This method does not normalize the result, and typically returns
119 * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
120 * As this is not very useful, this method is deprecated in favour
121 * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
122 * <p>
123 * Note that some OS's are NOT currently supported, including OS/390,
124 * OpenVMS.
125 * <pre>
126 * FileSystemUtils.freeSpace("C:"); // Windows
127 * FileSystemUtils.freeSpace("/volume"); // *nix
128 * </pre>
129 * The free space is calculated via the command line.
130 * It uses 'dir /-c' on Windows and 'df' on *nix.
131 *
132 * @param path the path to get free space for, not null, not empty on Unix
133 * @return the amount of free drive space on the drive or volume
134 * @throws IllegalArgumentException if the path is invalid
135 * @throws IllegalStateException if an error occurred in initialisation
136 * @throws IOException if an error occurs when finding the free space
137 * @since 1.1, enhanced OS support in 1.2 and 1.3
138 * @deprecated Use freeSpaceKb(String)
139 * Deprecated from 1.3, may be removed in 2.0
140 */
141 @Deprecated
142 public static long freeSpace(final String path) throws IOException {
143 return INSTANCE.freeSpaceOS(path, OS, false, -1);
144 }
145
146 //-----------------------------------------------------------------------
147 /**
148 * Returns the free space on a drive or volume in kilobytes by invoking
149 * the command line.
150 * <pre>
151 * FileSystemUtils.freeSpaceKb("C:"); // Windows
152 * FileSystemUtils.freeSpaceKb("/volume"); // *nix
153 * </pre>
154 * The free space is calculated via the command line.
155 * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
156 * <p>
157 * In order to work, you must be running Windows, or have a implementation of
158 * Unix df that supports GNU format when passed -k (or -kP). If you are going
159 * to rely on this code, please check that it works on your OS by running
160 * some simple tests to compare the command line with the output from this class.
161 * If your operating system isn't supported, please raise a JIRA call detailing
162 * the exact result from df -k and as much other detail as possible, thanks.
163 *
164 * @param path the path to get free space for, not null, not empty on Unix
165 * @return the amount of free drive space on the drive or volume in kilobytes
166 * @throws IllegalArgumentException if the path is invalid
167 * @throws IllegalStateException if an error occurred in initialisation
168 * @throws IOException if an error occurs when finding the free space
169 * @since 1.2, enhanced OS support in 1.3
170 */
171 public static long freeSpaceKb(final String path) throws IOException {
172 return freeSpaceKb(path, -1);
173 }
174 /**
175 * Returns the free space on a drive or volume in kilobytes by invoking
176 * the command line.
177 * <pre>
178 * FileSystemUtils.freeSpaceKb("C:"); // Windows
179 * FileSystemUtils.freeSpaceKb("/volume"); // *nix
180 * </pre>
181 * The free space is calculated via the command line.
182 * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
183 * <p>
184 * In order to work, you must be running Windows, or have a implementation of
185 * Unix df that supports GNU format when passed -k (or -kP). If you are going
186 * to rely on this code, please check that it works on your OS by running
187 * some simple tests to compare the command line with the output from this class.
188 * If your operating system isn't supported, please raise a JIRA call detailing
189 * the exact result from df -k and as much other detail as possible, thanks.
190 *
191 * @param path the path to get free space for, not null, not empty on Unix
192 * @param timeout The timout amount in milliseconds or no timeout if the value
193 * is zero or less
194 * @return the amount of free drive space on the drive or volume in kilobytes
195 * @throws IllegalArgumentException if the path is invalid
196 * @throws IllegalStateException if an error occurred in initialisation
197 * @throws IOException if an error occurs when finding the free space
198 * @since 2.0
199 */
200 public static long freeSpaceKb(final String path, final long timeout) throws IOException {
201 return INSTANCE.freeSpaceOS(path, OS, true, timeout);
202 }
203
204 /**
205 * Returns the disk size of the volume which holds the working directory.
206 * <p>
207 * Identical to:
208 * <pre>
209 * freeSpaceKb(new File(".").getAbsolutePath())
210 * </pre>
211 * @return the amount of free drive space on the drive or volume in kilobytes
212 * @throws IllegalStateException if an error occurred in initialisation
213 * @throws IOException if an error occurs when finding the free space
214 * @since 2.0
215 */
216 public static long freeSpaceKb() throws IOException {
217 return freeSpaceKb(-1);
218 }
219
220 /**
221 * Returns the disk size of the volume which holds the working directory.
222 * <p>
223 * Identical to:
224 * <pre>
225 * freeSpaceKb(new File(".").getAbsolutePath())
226 * </pre>
227 * @param timeout The timout amount in milliseconds or no timeout if the value
228 * is zero or less
229 * @return the amount of free drive space on the drive or volume in kilobytes
230 * @throws IllegalStateException if an error occurred in initialisation
231 * @throws IOException if an error occurs when finding the free space
232 * @since 2.0
233 */
234 public static long freeSpaceKb(final long timeout) throws IOException {
235 return freeSpaceKb(new File(".").getAbsolutePath(), timeout);
236 }
237
238 //-----------------------------------------------------------------------
239 /**
240 * Returns the free space on a drive or volume in a cross-platform manner.
241 * Note that some OS's are NOT currently supported, including OS/390.
242 * <pre>
243 * FileSystemUtils.freeSpace("C:"); // Windows
244 * FileSystemUtils.freeSpace("/volume"); // *nix
245 * </pre>
246 * The free space is calculated via the command line.
247 * It uses 'dir /-c' on Windows and 'df' on *nix.
248 *
249 * @param path the path to get free space for, not null, not empty on Unix
250 * @param os the operating system code
251 * @param kb whether to normalize to kilobytes
252 * @param timeout The timout amount in milliseconds or no timeout if the value
253 * is zero or less
254 * @return the amount of free drive space on the drive or volume
255 * @throws IllegalArgumentException if the path is invalid
256 * @throws IllegalStateException if an error occurred in initialisation
257 * @throws IOException if an error occurs when finding the free space
258 */
259 long freeSpaceOS(final String path, final int os, final boolean kb, final long timeout) throws IOException {
260 if (path == null) {
261 throw new IllegalArgumentException("Path must not be empty");
262 }
263 switch (os) {
264 case WINDOWS:
265 return kb ? freeSpaceWindows(path, timeout) / FileUtils.ONE_KB : freeSpaceWindows(path, timeout);
266 case UNIX:
267 return freeSpaceUnix(path, kb, false, timeout);
268 case POSIX_UNIX:
269 return freeSpaceUnix(path, kb, true, timeout);
270 case OTHER:
271 throw new IllegalStateException("Unsupported operating system");
272 default:
273 throw new IllegalStateException(
274 "Exception caught when determining operating system");
275 }
276 }
277
278 //-----------------------------------------------------------------------
279 /**
280 * Find free space on the Windows platform using the 'dir' command.
281 *
282 * @param path the path to get free space for, including the colon
283 * @param timeout The timout amount in milliseconds or no timeout if the value
284 * is zero or less
285 * @return the amount of free drive space on the drive
286 * @throws IOException if an error occurs
287 */
288 long freeSpaceWindows(String path, final long timeout) throws IOException {
289 path = FilenameUtils.normalize(path, false);
290 if (path.length() > 0 && path.charAt(0) != '"') {
291 path = "\"" + path + "\"";
292 }
293
294 // build and run the 'dir' command
295 final String[] cmdAttribs = new String[] {"cmd.exe", "/C", "dir /a /-c " + path};
296
297 // read in the output of the command to an ArrayList
298 final List<String> lines = performCommand(cmdAttribs, Integer.MAX_VALUE, timeout);
299
300 // now iterate over the lines we just read and find the LAST
301 // non-empty line (the free space bytes should be in the last element
302 // of the ArrayList anyway, but this will ensure it works even if it's
303 // not, still assuming it is on the last non-blank line)
304 for (int i = lines.size() - 1; i >= 0; i--) {
305 final String line = lines.get(i);
306 if (line.length() > 0) {
307 return parseDir(line, path);
308 }
309 }
310 // all lines are blank
311 throw new IOException(
312 "Command line 'dir /-c' did not return any info " +
313 "for path '" + path + "'");
314 }
315
316 /**
317 * Parses the Windows dir response last line
318 *
319 * @param line the line to parse
320 * @param path the path that was sent
321 * @return the number of bytes
322 * @throws IOException if an error occurs
323 */
324 long parseDir(final String line, final String path) throws IOException {
325 // read from the end of the line to find the last numeric
326 // character on the line, then continue until we find the first
327 // non-numeric character, and everything between that and the last
328 // numeric character inclusive is our free space bytes count
329 int bytesStart = 0;
330 int bytesEnd = 0;
331 int j = line.length() - 1;
332 innerLoop1: while (j >= 0) {
333 final char c = line.charAt(j);
334 if (Character.isDigit(c)) {
335 // found the last numeric character, this is the end of
336 // the free space bytes count
337 bytesEnd = j + 1;
338 break innerLoop1;
339 }
340 j--;
341 }
342 innerLoop2: while (j >= 0) {
343 final char c = line.charAt(j);
344 if (!Character.isDigit(c) && c != ',' && c != '.') {
345 // found the next non-numeric character, this is the
346 // beginning of the free space bytes count
347 bytesStart = j + 1;
348 break innerLoop2;
349 }
350 j--;
351 }
352 if (j < 0) {
353 throw new IOException(
354 "Command line 'dir /-c' did not return valid info " +
355 "for path '" + path + "'");
356 }
357
358 // remove commas and dots in the bytes count
359 final StringBuilder buf = new StringBuilder(line.substring(bytesStart, bytesEnd));
360 for (int k = 0; k < buf.length(); k++) {
361 if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
362 buf.deleteCharAt(k--);
363 }
364 }
365 return parseBytes(buf.toString(), path);
366 }
367
368 //-----------------------------------------------------------------------
369 /**
370 * Find free space on the *nix platform using the 'df' command.
371 *
372 * @param path the path to get free space for
373 * @param kb whether to normalize to kilobytes
374 * @param posix whether to use the posix standard format flag
375 * @param timeout The timout amount in milliseconds or no timeout if the value
376 * is zero or less
377 * @return the amount of free drive space on the volume
378 * @throws IOException if an error occurs
379 */
380 long freeSpaceUnix(final String path, final boolean kb, final boolean posix, final long timeout) throws IOException {
381 if (path.length() == 0) {
382 throw new IllegalArgumentException("Path must not be empty");
383 }
384
385 // build and run the 'dir' command
386 String flags = "-";
387 if (kb) {
388 flags += "k";
389 }
390 if (posix) {
391 flags += "P";
392 }
393 final String[] cmdAttribs =
394 flags.length() > 1 ? new String[] {DF, flags, path} : new String[] {DF, path};
395
396 // perform the command, asking for up to 3 lines (header, interesting, overflow)
397 final List<String> lines = performCommand(cmdAttribs, 3, timeout);
398 if (lines.size() < 2) {
399 // unknown problem, throw exception
400 throw new IOException(
401 "Command line '" + DF + "' did not return info as expected " +
402 "for path '" + path + "'- response was " + lines);
403 }
404 final String line2 = lines.get(1); // the line we're interested in
405
406 // Now, we tokenize the string. The fourth element is what we want.
407 StringTokenizer tok = new StringTokenizer(line2, " ");
408 if (tok.countTokens() < 4) {
409 // could be long Filesystem, thus data on third line
410 if (tok.countTokens() == 1 && lines.size() >= 3) {
411 final String line3 = lines.get(2); // the line may be interested in
412 tok = new StringTokenizer(line3, " ");
413 } else {
414 throw new IOException(
415 "Command line '" + DF + "' did not return data as expected " +
416 "for path '" + path + "'- check path is valid");
417 }
418 } else {
419 tok.nextToken(); // Ignore Filesystem
420 }
421 tok.nextToken(); // Ignore 1K-blocks
422 tok.nextToken(); // Ignore Used
423 final String freeSpace = tok.nextToken();
424 return parseBytes(freeSpace, path);
425 }
426
427 //-----------------------------------------------------------------------
428 /**
429 * Parses the bytes from a string.
430 *
431 * @param freeSpace the free space string
432 * @param path the path
433 * @return the number of bytes
434 * @throws IOException if an error occurs
435 */
436 long parseBytes(final String freeSpace, final String path) throws IOException {
437 try {
438 final long bytes = Long.parseLong(freeSpace);
439 if (bytes < 0) {
440 throw new IOException(
441 "Command line '" + DF + "' did not find free space in response " +
442 "for path '" + path + "'- check path is valid");
443 }
444 return bytes;
445
446 } catch (final NumberFormatException ex) {
447 throw new IOExceptionWithCause(
448 "Command line '" + DF + "' did not return numeric data as expected " +
449 "for path '" + path + "'- check path is valid", ex);
450 }
451 }
452
453 //-----------------------------------------------------------------------
454 /**
455 * Performs the os command.
456 *
457 * @param cmdAttribs the command line parameters
458 * @param max The maximum limit for the lines returned
459 * @param timeout The timout amount in milliseconds or no timeout if the value
460 * is zero or less
461 * @return the lines returned by the command, converted to lower-case
462 * @throws IOException if an error occurs
463 */
464 List<String> performCommand(final String[] cmdAttribs, final int max, final long timeout) throws IOException {
465 // this method does what it can to avoid the 'Too many open files' error
466 // based on trial and error and these links:
467 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
468 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
469 // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
470 // however, its still not perfect as the JDK support is so poor
471 // (see commons-exec or Ant for a better multi-threaded multi-os solution)
472
473 final List<String> lines = new ArrayList<String>(20);
474 Process proc = null;
475 InputStream in = null;
476 OutputStream out = null;
477 InputStream err = null;
478 BufferedReader inr = null;
479 try {
480
481 final Thread monitor = ThreadMonitor.start(timeout);
482
483 proc = openProcess(cmdAttribs);
484 in = proc.getInputStream();
485 out = proc.getOutputStream();
486 err = proc.getErrorStream();
487 // default charset is most likely appropriate here
488 inr = new BufferedReader(new InputStreamReader(in, Charset.defaultCharset()));
489 String line = inr.readLine();
490 while (line != null && lines.size() < max) {
491 line = line.toLowerCase(Locale.ENGLISH).trim();
492 lines.add(line);
493 line = inr.readLine();
494 }
495
496 proc.waitFor();
497
498 ThreadMonitor.stop(monitor);
499
500 if (proc.exitValue() != 0) {
501 // os command problem, throw exception
502 throw new IOException(
503 "Command line returned OS error code '" + proc.exitValue() +
504 "' for command " + Arrays.asList(cmdAttribs));
505 }
506 if (lines.isEmpty()) {
507 // unknown problem, throw exception
508 throw new IOException(
509 "Command line did not return any info " +
510 "for command " + Arrays.asList(cmdAttribs));
511 }
512 return lines;
513
514 } catch (final InterruptedException ex) {
515 throw new IOExceptionWithCause(
516 "Command line threw an InterruptedException " +
517 "for command " + Arrays.asList(cmdAttribs) + " timeout=" + timeout, ex);
518 } finally {
519 IOUtils.closeQuietly(in);
520 IOUtils.closeQuietly(out);
521 IOUtils.closeQuietly(err);
522 IOUtils.closeQuietly(inr);
523 if (proc != null) {
524 proc.destroy();
525 }
526 }
527 }
528
529 /**
530 * Opens the process to the operating system.
531 *
532 * @param cmdAttribs the command line parameters
533 * @return the process
534 * @throws IOException if an error occurs
535 */
536 Process openProcess(final String[] cmdAttribs) throws IOException {
537 return Runtime.getRuntime().exec(cmdAttribs);
538 }
539
540 }