001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.commons.io;
018
019 import java.io.BufferedReader;
020 import java.io.File;
021 import java.io.IOException;
022 import java.io.InputStream;
023 import java.io.InputStreamReader;
024 import java.io.OutputStream;
025 import java.util.ArrayList;
026 import java.util.Arrays;
027 import java.util.List;
028 import java.util.Locale;
029 import java.util.StringTokenizer;
030
031 /**
032 * General File System utilities.
033 * <p>
034 * This class provides static utility methods for general file system
035 * functions not provided via the JDK {@link java.io.File File} class.
036 * <p>
037 * The current functions provided are:
038 * <ul>
039 * <li>Get the free space on a drive
040 * </ul>
041 *
042 * @version $Id: FileSystemUtils.java 1304052 2012-03-22 20:55:29Z ggregory $
043 * @since 1.1
044 */
045 public class FileSystemUtils {
046
047 /** Singleton instance, used mainly for testing. */
048 private static final FileSystemUtils INSTANCE = new FileSystemUtils();
049
050 /** Operating system state flag for error. */
051 private static final int INIT_PROBLEM = -1;
052 /** Operating system state flag for neither Unix nor Windows. */
053 private static final int OTHER = 0;
054 /** Operating system state flag for Windows. */
055 private static final int WINDOWS = 1;
056 /** Operating system state flag for Unix. */
057 private static final int UNIX = 2;
058 /** Operating system state flag for Posix flavour Unix. */
059 private static final int POSIX_UNIX = 3;
060
061 /** The operating system flag. */
062 private static final int OS;
063
064 /** The path to df */
065 private static final String DF;
066
067 static {
068 int os = OTHER;
069 String dfPath = "df";
070 try {
071 String osName = System.getProperty("os.name");
072 if (osName == null) {
073 throw new IOException("os.name not found");
074 }
075 osName = osName.toLowerCase(Locale.ENGLISH);
076 // match
077 if (osName.indexOf("windows") != -1) {
078 os = WINDOWS;
079 } else if (osName.indexOf("linux") != -1 ||
080 osName.indexOf("mpe/ix") != -1 ||
081 osName.indexOf("freebsd") != -1 ||
082 osName.indexOf("irix") != -1 ||
083 osName.indexOf("digital unix") != -1 ||
084 osName.indexOf("unix") != -1 ||
085 osName.indexOf("mac os x") != -1) {
086 os = UNIX;
087 } else if (osName.indexOf("sun os") != -1 ||
088 osName.indexOf("sunos") != -1 ||
089 osName.indexOf("solaris") != -1) {
090 os = POSIX_UNIX;
091 dfPath = "/usr/xpg4/bin/df";
092 } else if (osName.indexOf("hp-ux") != -1 ||
093 osName.indexOf("aix") != -1) {
094 os = POSIX_UNIX;
095 } else {
096 os = OTHER;
097 }
098
099 } catch (Exception ex) {
100 os = INIT_PROBLEM;
101 }
102 OS = os;
103 DF = dfPath;
104 }
105
106 /**
107 * Instances should NOT be constructed in standard programming.
108 */
109 public FileSystemUtils() {
110 super();
111 }
112
113 //-----------------------------------------------------------------------
114 /**
115 * Returns the free space on a drive or volume by invoking
116 * the command line.
117 * This method does not normalize the result, and typically returns
118 * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
119 * As this is not very useful, this method is deprecated in favour
120 * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
121 * <p>
122 * Note that some OS's are NOT currently supported, including OS/390,
123 * OpenVMS.
124 * <pre>
125 * FileSystemUtils.freeSpace("C:"); // Windows
126 * FileSystemUtils.freeSpace("/volume"); // *nix
127 * </pre>
128 * The free space is calculated via the command line.
129 * It uses 'dir /-c' on Windows and 'df' on *nix.
130 *
131 * @param path the path to get free space for, not null, not empty on Unix
132 * @return the amount of free drive space on the drive or volume
133 * @throws IllegalArgumentException if the path is invalid
134 * @throws IllegalStateException if an error occurred in initialisation
135 * @throws IOException if an error occurs when finding the free space
136 * @since 1.1, enhanced OS support in 1.2 and 1.3
137 * @deprecated Use freeSpaceKb(String)
138 * Deprecated from 1.3, may be removed in 2.0
139 */
140 @Deprecated
141 public static long freeSpace(String path) throws IOException {
142 return INSTANCE.freeSpaceOS(path, OS, false, -1);
143 }
144
145 //-----------------------------------------------------------------------
146 /**
147 * Returns the free space on a drive or volume in kilobytes by invoking
148 * the command line.
149 * <pre>
150 * FileSystemUtils.freeSpaceKb("C:"); // Windows
151 * FileSystemUtils.freeSpaceKb("/volume"); // *nix
152 * </pre>
153 * The free space is calculated via the command line.
154 * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
155 * <p>
156 * In order to work, you must be running Windows, or have a implementation of
157 * Unix df that supports GNU format when passed -k (or -kP). If you are going
158 * to rely on this code, please check that it works on your OS by running
159 * some simple tests to compare the command line with the output from this class.
160 * If your operating system isn't supported, please raise a JIRA call detailing
161 * the exact result from df -k and as much other detail as possible, thanks.
162 *
163 * @param path the path to get free space for, not null, not empty on Unix
164 * @return the amount of free drive space on the drive or volume in kilobytes
165 * @throws IllegalArgumentException if the path is invalid
166 * @throws IllegalStateException if an error occurred in initialisation
167 * @throws IOException if an error occurs when finding the free space
168 * @since 1.2, enhanced OS support in 1.3
169 */
170 public static long freeSpaceKb(String path) throws IOException {
171 return freeSpaceKb(path, -1);
172 }
173 /**
174 * Returns the free space on a drive or volume in kilobytes by invoking
175 * the command line.
176 * <pre>
177 * FileSystemUtils.freeSpaceKb("C:"); // Windows
178 * FileSystemUtils.freeSpaceKb("/volume"); // *nix
179 * </pre>
180 * The free space is calculated via the command line.
181 * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
182 * <p>
183 * In order to work, you must be running Windows, or have a implementation of
184 * Unix df that supports GNU format when passed -k (or -kP). If you are going
185 * to rely on this code, please check that it works on your OS by running
186 * some simple tests to compare the command line with the output from this class.
187 * If your operating system isn't supported, please raise a JIRA call detailing
188 * the exact result from df -k and as much other detail as possible, thanks.
189 *
190 * @param path the path to get free space for, not null, not empty on Unix
191 * @param timeout The timout amount in milliseconds or no timeout if the value
192 * is zero or less
193 * @return the amount of free drive space on the drive or volume in kilobytes
194 * @throws IllegalArgumentException if the path is invalid
195 * @throws IllegalStateException if an error occurred in initialisation
196 * @throws IOException if an error occurs when finding the free space
197 * @since 2.0
198 */
199 public static long freeSpaceKb(String path, long timeout) throws IOException {
200 return INSTANCE.freeSpaceOS(path, OS, true, timeout);
201 }
202
203 /**
204 * Returns the disk size of the volume which holds the working directory.
205 * <p>
206 * Identical to:
207 * <pre>
208 * freeSpaceKb(new File(".").getAbsolutePath())
209 * </pre>
210 * @return the amount of free drive space on the drive or volume in kilobytes
211 * @throws IllegalStateException if an error occurred in initialisation
212 * @throws IOException if an error occurs when finding the free space
213 * @since 2.0
214 */
215 public static long freeSpaceKb() throws IOException {
216 return freeSpaceKb(-1);
217 }
218
219 /**
220 * Returns the disk size of the volume which holds the working directory.
221 * <p>
222 * Identical to:
223 * <pre>
224 * freeSpaceKb(new File(".").getAbsolutePath())
225 * </pre>
226 * @param timeout The timout amount in milliseconds or no timeout if the value
227 * is zero or less
228 * @return the amount of free drive space on the drive or volume in kilobytes
229 * @throws IllegalStateException if an error occurred in initialisation
230 * @throws IOException if an error occurs when finding the free space
231 * @since 2.0
232 */
233 public static long freeSpaceKb(long timeout) throws IOException {
234 return freeSpaceKb(new File(".").getAbsolutePath(), timeout);
235 }
236
237 //-----------------------------------------------------------------------
238 /**
239 * Returns the free space on a drive or volume in a cross-platform manner.
240 * Note that some OS's are NOT currently supported, including OS/390.
241 * <pre>
242 * FileSystemUtils.freeSpace("C:"); // Windows
243 * FileSystemUtils.freeSpace("/volume"); // *nix
244 * </pre>
245 * The free space is calculated via the command line.
246 * It uses 'dir /-c' on Windows and 'df' on *nix.
247 *
248 * @param path the path to get free space for, not null, not empty on Unix
249 * @param os the operating system code
250 * @param kb whether to normalize to kilobytes
251 * @param timeout The timout amount in milliseconds or no timeout if the value
252 * is zero or less
253 * @return the amount of free drive space on the drive or volume
254 * @throws IllegalArgumentException if the path is invalid
255 * @throws IllegalStateException if an error occurred in initialisation
256 * @throws IOException if an error occurs when finding the free space
257 */
258 long freeSpaceOS(String path, int os, boolean kb, long timeout) throws IOException {
259 if (path == null) {
260 throw new IllegalArgumentException("Path must not be empty");
261 }
262 switch (os) {
263 case WINDOWS:
264 return kb ? freeSpaceWindows(path, timeout) / FileUtils.ONE_KB : freeSpaceWindows(path, timeout);
265 case UNIX:
266 return freeSpaceUnix(path, kb, false, timeout);
267 case POSIX_UNIX:
268 return freeSpaceUnix(path, kb, true, timeout);
269 case OTHER:
270 throw new IllegalStateException("Unsupported operating system");
271 default:
272 throw new IllegalStateException(
273 "Exception caught when determining operating system");
274 }
275 }
276
277 //-----------------------------------------------------------------------
278 /**
279 * Find free space on the Windows platform using the 'dir' command.
280 *
281 * @param path the path to get free space for, including the colon
282 * @param timeout The timout amount in milliseconds or no timeout if the value
283 * is zero or less
284 * @return the amount of free drive space on the drive
285 * @throws IOException if an error occurs
286 */
287 long freeSpaceWindows(String path, long timeout) throws IOException {
288 path = FilenameUtils.normalize(path, false);
289 if (path.length() > 0 && path.charAt(0) != '"') {
290 path = "\"" + path + "\"";
291 }
292
293 // build and run the 'dir' command
294 String[] cmdAttribs = new String[] {"cmd.exe", "/C", "dir /a /-c " + path};
295
296 // read in the output of the command to an ArrayList
297 List<String> lines = performCommand(cmdAttribs, Integer.MAX_VALUE, timeout);
298
299 // now iterate over the lines we just read and find the LAST
300 // non-empty line (the free space bytes should be in the last element
301 // of the ArrayList anyway, but this will ensure it works even if it's
302 // not, still assuming it is on the last non-blank line)
303 for (int i = lines.size() - 1; i >= 0; i--) {
304 String line = lines.get(i);
305 if (line.length() > 0) {
306 return parseDir(line, path);
307 }
308 }
309 // all lines are blank
310 throw new IOException(
311 "Command line 'dir /-c' did not return any info " +
312 "for path '" + path + "'");
313 }
314
315 /**
316 * Parses the Windows dir response last line
317 *
318 * @param line the line to parse
319 * @param path the path that was sent
320 * @return the number of bytes
321 * @throws IOException if an error occurs
322 */
323 long parseDir(String line, String path) throws IOException {
324 // read from the end of the line to find the last numeric
325 // character on the line, then continue until we find the first
326 // non-numeric character, and everything between that and the last
327 // numeric character inclusive is our free space bytes count
328 int bytesStart = 0;
329 int bytesEnd = 0;
330 int j = line.length() - 1;
331 innerLoop1: while (j >= 0) {
332 char c = line.charAt(j);
333 if (Character.isDigit(c)) {
334 // found the last numeric character, this is the end of
335 // the free space bytes count
336 bytesEnd = j + 1;
337 break innerLoop1;
338 }
339 j--;
340 }
341 innerLoop2: while (j >= 0) {
342 char c = line.charAt(j);
343 if (!Character.isDigit(c) && c != ',' && c != '.') {
344 // found the next non-numeric character, this is the
345 // beginning of the free space bytes count
346 bytesStart = j + 1;
347 break innerLoop2;
348 }
349 j--;
350 }
351 if (j < 0) {
352 throw new IOException(
353 "Command line 'dir /-c' did not return valid info " +
354 "for path '" + path + "'");
355 }
356
357 // remove commas and dots in the bytes count
358 StringBuilder buf = new StringBuilder(line.substring(bytesStart, bytesEnd));
359 for (int k = 0; k < buf.length(); k++) {
360 if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
361 buf.deleteCharAt(k--);
362 }
363 }
364 return parseBytes(buf.toString(), path);
365 }
366
367 //-----------------------------------------------------------------------
368 /**
369 * Find free space on the *nix platform using the 'df' command.
370 *
371 * @param path the path to get free space for
372 * @param kb whether to normalize to kilobytes
373 * @param posix whether to use the posix standard format flag
374 * @param timeout The timout amount in milliseconds or no timeout if the value
375 * is zero or less
376 * @return the amount of free drive space on the volume
377 * @throws IOException if an error occurs
378 */
379 long freeSpaceUnix(String path, boolean kb, boolean posix, long timeout) throws IOException {
380 if (path.length() == 0) {
381 throw new IllegalArgumentException("Path must not be empty");
382 }
383
384 // build and run the 'dir' command
385 String flags = "-";
386 if (kb) {
387 flags += "k";
388 }
389 if (posix) {
390 flags += "P";
391 }
392 String[] cmdAttribs =
393 flags.length() > 1 ? new String[] {DF, flags, path} : new String[] {DF, path};
394
395 // perform the command, asking for up to 3 lines (header, interesting, overflow)
396 List<String> lines = performCommand(cmdAttribs, 3, timeout);
397 if (lines.size() < 2) {
398 // unknown problem, throw exception
399 throw new IOException(
400 "Command line '" + DF + "' did not return info as expected " +
401 "for path '" + path + "'- response was " + lines);
402 }
403 String line2 = lines.get(1); // the line we're interested in
404
405 // Now, we tokenize the string. The fourth element is what we want.
406 StringTokenizer tok = new StringTokenizer(line2, " ");
407 if (tok.countTokens() < 4) {
408 // could be long Filesystem, thus data on third line
409 if (tok.countTokens() == 1 && lines.size() >= 3) {
410 String line3 = lines.get(2); // the line may be interested in
411 tok = new StringTokenizer(line3, " ");
412 } else {
413 throw new IOException(
414 "Command line '" + DF + "' did not return data as expected " +
415 "for path '" + path + "'- check path is valid");
416 }
417 } else {
418 tok.nextToken(); // Ignore Filesystem
419 }
420 tok.nextToken(); // Ignore 1K-blocks
421 tok.nextToken(); // Ignore Used
422 String freeSpace = tok.nextToken();
423 return parseBytes(freeSpace, path);
424 }
425
426 //-----------------------------------------------------------------------
427 /**
428 * Parses the bytes from a string.
429 *
430 * @param freeSpace the free space string
431 * @param path the path
432 * @return the number of bytes
433 * @throws IOException if an error occurs
434 */
435 long parseBytes(String freeSpace, String path) throws IOException {
436 try {
437 long bytes = Long.parseLong(freeSpace);
438 if (bytes < 0) {
439 throw new IOException(
440 "Command line '" + DF + "' did not find free space in response " +
441 "for path '" + path + "'- check path is valid");
442 }
443 return bytes;
444
445 } catch (NumberFormatException ex) {
446 throw new IOExceptionWithCause(
447 "Command line '" + DF + "' did not return numeric data as expected " +
448 "for path '" + path + "'- check path is valid", ex);
449 }
450 }
451
452 //-----------------------------------------------------------------------
453 /**
454 * Performs the os command.
455 *
456 * @param cmdAttribs the command line parameters
457 * @param max The maximum limit for the lines returned
458 * @param timeout The timout amount in milliseconds or no timeout if the value
459 * is zero or less
460 * @return the parsed data
461 * @throws IOException if an error occurs
462 */
463 List<String> performCommand(String[] cmdAttribs, int max, long timeout) throws IOException {
464 // this method does what it can to avoid the 'Too many open files' error
465 // based on trial and error and these links:
466 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
467 // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
468 // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
469 // however, its still not perfect as the JDK support is so poor
470 // (see commond-exec or ant for a better multi-threaded multi-os solution)
471
472 List<String> lines = new ArrayList<String>(20);
473 Process proc = null;
474 InputStream in = null;
475 OutputStream out = null;
476 InputStream err = null;
477 BufferedReader inr = null;
478 try {
479
480 Thread monitor = ThreadMonitor.start(timeout);
481
482 proc = openProcess(cmdAttribs);
483 in = proc.getInputStream();
484 out = proc.getOutputStream();
485 err = proc.getErrorStream();
486 inr = new BufferedReader(new InputStreamReader(in));
487 String line = inr.readLine();
488 while (line != null && lines.size() < max) {
489 line = line.toLowerCase(Locale.ENGLISH).trim();
490 lines.add(line);
491 line = inr.readLine();
492 }
493
494 proc.waitFor();
495
496 ThreadMonitor.stop(monitor);
497
498 if (proc.exitValue() != 0) {
499 // os command problem, throw exception
500 throw new IOException(
501 "Command line returned OS error code '" + proc.exitValue() +
502 "' for command " + Arrays.asList(cmdAttribs));
503 }
504 if (lines.isEmpty()) {
505 // unknown problem, throw exception
506 throw new IOException(
507 "Command line did not return any info " +
508 "for command " + Arrays.asList(cmdAttribs));
509 }
510 return lines;
511
512 } catch (InterruptedException ex) {
513 throw new IOExceptionWithCause(
514 "Command line threw an InterruptedException " +
515 "for command " + Arrays.asList(cmdAttribs) + " timeout=" + timeout, ex);
516 } finally {
517 IOUtils.closeQuietly(in);
518 IOUtils.closeQuietly(out);
519 IOUtils.closeQuietly(err);
520 IOUtils.closeQuietly(inr);
521 if (proc != null) {
522 proc.destroy();
523 }
524 }
525 }
526
527 /**
528 * Opens the process to the operating system.
529 *
530 * @param cmdAttribs the command line parameters
531 * @return the process
532 * @throws IOException if an error occurs
533 */
534 Process openProcess(String[] cmdAttribs) throws IOException {
535 return Runtime.getRuntime().exec(cmdAttribs);
536 }
537
538 }