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 */
017package org.apache.commons.io;
018
019import java.io.BufferedReader;
020import java.io.File;
021import java.io.IOException;
022import java.io.InputStream;
023import java.io.InputStreamReader;
024import java.io.OutputStream;
025import java.nio.charset.Charset;
026import java.time.Duration;
027import java.util.ArrayList;
028import java.util.Arrays;
029import java.util.List;
030import java.util.Locale;
031import java.util.StringTokenizer;
032
033/**
034 * General File System utilities.
035 * <p>
036 * This class provides static utility methods for general file system
037 * functions not provided via the JDK {@link java.io.File File} class.
038 * <p>
039 * The current functions provided are:
040 * <ul>
041 * <li>Get the free space on a drive
042 * </ul>
043 *
044 * @since 1.1
045 * @deprecated As of 2.6 deprecated without replacement. Use equivalent
046 *  methods in {@link java.nio.file.FileStore} instead, e.g.
047 *  {@code Files.getFileStore(Paths.get("/home")).getUsableSpace()}
048 *  or iterate over {@code FileSystems.getDefault().getFileStores()}
049 */
050@Deprecated
051public class FileSystemUtils {
052
053    /** Singleton instance, used mainly for testing. */
054    private static final FileSystemUtils INSTANCE = new FileSystemUtils();
055
056    /** Operating system state flag for error. */
057    private static final int INIT_PROBLEM = -1;
058    /** Operating system state flag for neither Unix nor Windows. */
059    private static final int OTHER = 0;
060    /** Operating system state flag for Windows. */
061    private static final int WINDOWS = 1;
062    /** Operating system state flag for Unix. */
063    private static final int UNIX = 2;
064    /** Operating system state flag for Posix flavour Unix. */
065    private static final int POSIX_UNIX = 3;
066
067    /** The operating system flag. */
068    private static final int OS;
069
070    /** The path to df */
071    private static final String DF;
072
073    static {
074        int os = OTHER;
075        String dfPath = "df";
076        try {
077            String osName = System.getProperty("os.name");
078            if (osName == null) {
079                throw new IOException("os.name not found");
080            }
081            osName = osName.toLowerCase(Locale.ENGLISH);
082            // match
083            if (osName.contains("windows")) {
084                os = WINDOWS;
085            } else if (osName.contains("linux") ||
086                    osName.contains("mpe/ix") ||
087                    osName.contains("freebsd") ||
088                    osName.contains("openbsd") ||
089                    osName.contains("irix") ||
090                    osName.contains("digital unix") ||
091                    osName.contains("unix") ||
092                    osName.contains("mac os x")) {
093                os = UNIX;
094            } else if (osName.contains("sun os") ||
095                    osName.contains("sunos") ||
096                    osName.contains("solaris")) {
097                os = POSIX_UNIX;
098                dfPath = "/usr/xpg4/bin/df";
099            } else if (osName.contains("hp-ux") ||
100                    osName.contains("aix")) {
101                os = POSIX_UNIX;
102            }
103
104        } catch (final Exception ex) {
105            os = INIT_PROBLEM;
106        }
107        OS = os;
108        DF = dfPath;
109    }
110
111    /**
112     * Instances should NOT be constructed in standard programming.
113     */
114    public FileSystemUtils() {
115    }
116
117    /**
118     * Returns the free space on a drive or volume by invoking
119     * the command line.
120     * This method does not normalize the result, and typically returns
121     * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
122     * As this is not very useful, this method is deprecated in favour
123     * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
124     * <p>
125     * Note that some OS's are NOT currently supported, including OS/390,
126     * OpenVMS.
127     * <pre>
128     * FileSystemUtils.freeSpace("C:");       // Windows
129     * FileSystemUtils.freeSpace("/volume");  // *nix
130     * </pre>
131     * The free space is calculated via the command line.
132     * It uses 'dir /-c' on Windows and 'df' on *nix.
133     *
134     * @param path  the path to get free space for, not null, not empty on Unix
135     * @return the amount of free drive space on the drive or volume
136     * @throws IllegalArgumentException if the path is invalid
137     * @throws IllegalStateException if an error occurred in initialisation
138     * @throws IOException if an error occurs when finding the free space
139     * @since 1.1, enhanced OS support in 1.2 and 1.3
140     * @deprecated Use freeSpaceKb(String)
141     *  Deprecated from 1.3, may be removed in 2.0
142     */
143    @Deprecated
144    public static long freeSpace(final String path) throws IOException {
145        return INSTANCE.freeSpaceOS(path, OS, false, Duration.ofMillis(-1));
146    }
147
148    /**
149     * Returns the free space on a drive or volume in kibibytes (1024 bytes)
150     * by invoking the command line.
151     * <pre>
152     * FileSystemUtils.freeSpaceKb("C:");       // Windows
153     * FileSystemUtils.freeSpaceKb("/volume");  // *nix
154     * </pre>
155     * The free space is calculated via the command line.
156     * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
157     * <p>
158     * In order to work, you must be running Windows, or have a implementation of
159     * Unix df that supports GNU format when passed -k (or -kP). If you are going
160     * to rely on this code, please check that it works on your OS by running
161     * some simple tests to compare the command line with the output from this class.
162     * If your operating system isn't supported, please raise a JIRA call detailing
163     * the exact result from df -k and as much other detail as possible, thanks.
164     *
165     * @param path  the path to get free space for, not null, not empty on Unix
166     * @return the amount of free drive space on the drive or volume in kilobytes
167     * @throws IllegalArgumentException if the path is invalid
168     * @throws IllegalStateException if an error occurred in initialisation
169     * @throws IOException if an error occurs when finding the free space
170     * @since 1.2, enhanced OS support in 1.3
171     * @deprecated As of 2.6 deprecated without replacement. Please use {@link java.nio.file.FileStore#getUsableSpace()}.
172     */
173    @Deprecated
174    public static long freeSpaceKb(final String path) throws IOException {
175        return freeSpaceKb(path, -1);
176    }
177    /**
178     * Returns the free space on a drive or volume in kibibytes (1024 bytes)
179     * by invoking the command line.
180     * <pre>
181     * FileSystemUtils.freeSpaceKb("C:");       // Windows
182     * FileSystemUtils.freeSpaceKb("/volume");  // *nix
183     * </pre>
184     * The free space is calculated via the command line.
185     * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
186     * <p>
187     * In order to work, you must be running Windows, or have a implementation of
188     * Unix df that supports GNU format when passed -k (or -kP). If you are going
189     * to rely on this code, please check that it works on your OS by running
190     * some simple tests to compare the command line with the output from this class.
191     * If your operating system isn't supported, please raise a JIRA call detailing
192     * the exact result from df -k and as much other detail as possible, thanks.
193     *
194     * @param path  the path to get free space for, not null, not empty on Unix
195     * @param timeout The timeout amount in milliseconds or no timeout if the value
196     *  is zero or less
197     * @return the amount of free drive space on the drive or volume in kilobytes
198     * @throws IllegalArgumentException if the path is invalid
199     * @throws IllegalStateException if an error occurred in initialisation
200     * @throws IOException if an error occurs when finding the free space
201     * @since 2.0
202     * @deprecated As of 2.6 deprecated without replacement. Please use {@link java.nio.file.FileStore#getUsableSpace()}.
203     */
204    @Deprecated
205    public static long freeSpaceKb(final String path, final long timeout) throws IOException {
206        return INSTANCE.freeSpaceOS(path, OS, true, Duration.ofMillis(timeout));
207    }
208
209    /**
210     * Returns the free space for the working directory
211     * in kibibytes (1024 bytes) by invoking the command line.
212     * <p>
213     * Identical to:
214     * <pre>
215     * freeSpaceKb(new File(".").getAbsolutePath())
216     * </pre>
217     * @return the amount of free drive space on the drive or volume in kilobytes
218     * @throws IllegalStateException if an error occurred in initialisation
219     * @throws IOException if an error occurs when finding the free space
220     * @since 2.0
221     * @deprecated As of 2.6 deprecated without replacement. Please use {@link java.nio.file.FileStore#getUsableSpace()}.
222     */
223    @Deprecated
224    public static long freeSpaceKb() throws IOException {
225        return freeSpaceKb(-1);
226    }
227
228    /**
229     * Returns the free space for the working directory
230     * in kibibytes (1024 bytes) by invoking the command line.
231     * <p>
232     * Identical to:
233     * <pre>
234     * freeSpaceKb(new File(".").getAbsolutePath())
235     * </pre>
236     * @param timeout The timeout amount in milliseconds or no timeout if the value
237     *  is zero or less
238     * @return the amount of free drive space on the drive or volume in kilobytes
239     * @throws IllegalStateException if an error occurred in initialisation
240     * @throws IOException if an error occurs when finding the free space
241     * @since 2.0
242     * @deprecated As of 2.6 deprecated without replacement. Please use {@link java.nio.file.FileStore#getUsableSpace()}.
243     */
244    @Deprecated
245    public static long freeSpaceKb(final long timeout) throws IOException {
246        return freeSpaceKb(new File(".").getAbsolutePath(), timeout);
247    }
248
249    /**
250     * Returns the free space on a drive or volume in a cross-platform manner.
251     * Note that some OS's are NOT currently supported, including OS/390.
252     * <pre>
253     * FileSystemUtils.freeSpace("C:");  // Windows
254     * FileSystemUtils.freeSpace("/volume");  // *nix
255     * </pre>
256     * The free space is calculated via the command line.
257     * It uses 'dir /-c' on Windows and 'df' on *nix.
258     *
259     * @param path  the path to get free space for, not null, not empty on Unix
260     * @param os  the operating system code
261     * @param kb  whether to normalize to kilobytes
262     * @param timeout The timeout amount in milliseconds or no timeout if the value
263     *  is zero or less
264     * @return the amount of free drive space on the drive or volume
265     * @throws IllegalArgumentException if the path is invalid
266     * @throws IllegalStateException if an error occurred in initialisation
267     * @throws IOException if an error occurs when finding the free space
268     */
269    long freeSpaceOS(final String path, final int os, final boolean kb, final Duration timeout) throws IOException {
270        if (path == null) {
271            throw new IllegalArgumentException("Path must not be null");
272        }
273        switch (os) {
274            case WINDOWS:
275                return kb ? freeSpaceWindows(path, timeout) / FileUtils.ONE_KB : freeSpaceWindows(path, timeout);
276            case UNIX:
277                return freeSpaceUnix(path, kb, false, timeout);
278            case POSIX_UNIX:
279                return freeSpaceUnix(path, kb, true, timeout);
280            case OTHER:
281                throw new IllegalStateException("Unsupported operating system");
282            default:
283                throw new IllegalStateException(
284                  "Exception caught when determining operating system");
285        }
286    }
287
288    /**
289     * Find free space on the Windows platform using the 'dir' command.
290     *
291     * @param path  the path to get free space for, including the colon
292     * @param timeout The timeout amount in milliseconds or no timeout if the value
293     *  is zero or less
294     * @return the amount of free drive space on the drive
295     * @throws IOException if an error occurs
296     */
297    long freeSpaceWindows(final String path, final Duration timeout) throws IOException {
298        String normPath = FilenameUtils.normalize(path, false);
299        if (normPath == null) {
300            throw new IllegalArgumentException(path);
301        }
302        if (!normPath.isEmpty() && normPath.charAt(0) != '"') {
303            normPath = "\"" + normPath + "\"";
304        }
305
306        // build and run the 'dir' command
307        final String[] cmdAttribs = {"cmd.exe", "/C", "dir /a /-c " + normPath};
308
309        // read in the output of the command to an ArrayList
310        final List<String> lines = performCommand(cmdAttribs, Integer.MAX_VALUE, timeout);
311
312        // now iterate over the lines we just read and find the LAST
313        // non-empty line (the free space bytes should be in the last element
314        // of the ArrayList anyway, but this will ensure it works even if it's
315        // not, still assuming it is on the last non-blank line)
316        for (int i = lines.size() - 1; i >= 0; i--) {
317            final String line = lines.get(i);
318            if (!line.isEmpty()) {
319                return parseDir(line, normPath);
320            }
321        }
322        // all lines are blank
323        throw new IOException(
324                "Command line 'dir /-c' did not return any info " +
325                "for path '" + normPath + "'");
326    }
327
328    /**
329     * Parses the Windows dir response last line
330     *
331     * @param line  the line to parse
332     * @param path  the path that was sent
333     * @return the number of bytes
334     * @throws IOException if an error occurs
335     */
336    long parseDir(final String line, final String path) throws IOException {
337        // read from the end of the line to find the last numeric
338        // character on the line, then continue until we find the first
339        // non-numeric character, and everything between that and the last
340        // numeric character inclusive is our free space bytes count
341        int bytesStart = 0;
342        int bytesEnd = 0;
343        int j = line.length() - 1;
344        innerLoop1: while (j >= 0) {
345            final char c = line.charAt(j);
346            if (Character.isDigit(c)) {
347              // found the last numeric character, this is the end of
348              // the free space bytes count
349              bytesEnd = j + 1;
350              break innerLoop1;
351            }
352            j--;
353        }
354        innerLoop2: while (j >= 0) {
355            final char c = line.charAt(j);
356            if (!Character.isDigit(c) && c != ',' && c != '.') {
357              // found the next non-numeric character, this is the
358              // beginning of the free space bytes count
359              bytesStart = j + 1;
360              break innerLoop2;
361            }
362            j--;
363        }
364        if (j < 0) {
365            throw new IOException(
366                    "Command line 'dir /-c' did not return valid info " +
367                    "for path '" + path + "'");
368        }
369
370        // remove commas and dots in the bytes count
371        final StringBuilder buf = new StringBuilder(line.substring(bytesStart, bytesEnd));
372        for (int k = 0; k < buf.length(); k++) {
373            if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
374                buf.deleteCharAt(k--);
375            }
376        }
377        return parseBytes(buf.toString(), path);
378    }
379
380    /**
381     * Find free space on the *nix platform using the 'df' command.
382     *
383     * @param path  the path to get free space for
384     * @param kb  whether to normalize to kilobytes
385     * @param posix  whether to use the POSIX standard format flag
386     * @param timeout The timeout amount in milliseconds or no timeout if the value
387     *  is zero or less
388     * @return the amount of free drive space on the volume
389     * @throws IOException if an error occurs
390     */
391    long freeSpaceUnix(final String path, final boolean kb, final boolean posix, final Duration timeout)
392            throws IOException {
393        if (path.isEmpty()) {
394            throw new IllegalArgumentException("Path must not be empty");
395        }
396
397        // build and run the 'dir' command
398        String flags = "-";
399        if (kb) {
400            flags += "k";
401        }
402        if (posix) {
403            flags += "P";
404        }
405        final String[] cmdAttribs =
406            flags.length() > 1 ? new String[] {DF, flags, path} : new String[] {DF, path};
407
408        // perform the command, asking for up to 3 lines (header, interesting, overflow)
409        final List<String> lines = performCommand(cmdAttribs, 3, timeout);
410        if (lines.size() < 2) {
411            // unknown problem, throw exception
412            throw new IOException(
413                    "Command line '" + DF + "' did not return info as expected " +
414                    "for path '" + path + "'- response was " + lines);
415        }
416        final String line2 = lines.get(1); // the line we're interested in
417
418        // Now, we tokenize the string. The fourth element is what we want.
419        StringTokenizer tok = new StringTokenizer(line2, " ");
420        if (tok.countTokens() < 4) {
421            // could be long Filesystem, thus data on third line
422            if ((tok.countTokens() != 1) || (lines.size() < 3)) {
423                throw new IOException(
424                        "Command line '" + DF + "' did not return data as expected " +
425                        "for path '" + path + "'- check path is valid");
426            }
427            final String line3 = lines.get(2); // the line may be interested in
428            tok = new StringTokenizer(line3, " ");
429        } else {
430            tok.nextToken(); // Ignore Filesystem
431        }
432        tok.nextToken(); // Ignore 1K-blocks
433        tok.nextToken(); // Ignore Used
434        final String freeSpace = tok.nextToken();
435        return parseBytes(freeSpace, path);
436    }
437
438    /**
439     * Parses the bytes from a string.
440     *
441     * @param freeSpace  the free space string
442     * @param path  the path
443     * @return the number of bytes
444     * @throws IOException if an error occurs
445     */
446    long parseBytes(final String freeSpace, final String path) throws IOException {
447        try {
448            final long bytes = Long.parseLong(freeSpace);
449            if (bytes < 0) {
450                throw new IOException(
451                        "Command line '" + DF + "' did not find free space in response " +
452                        "for path '" + path + "'- check path is valid");
453            }
454            return bytes;
455
456        } catch (final NumberFormatException ex) {
457            throw new IOException(
458                    "Command line '" + DF + "' did not return numeric data as expected " +
459                    "for path '" + path + "'- check path is valid", ex);
460        }
461    }
462
463    /**
464     * Performs an OS command.
465     *
466     * @param cmdAttribs  the command line parameters
467     * @param max The maximum limit for the lines returned
468     * @param timeout The timeout amount in milliseconds or no timeout if the value
469     *  is zero or less
470     * @return the lines returned by the command, converted to lower-case
471     * @throws IOException if an error occurs
472     */
473    List<String> performCommand(final String[] cmdAttribs, final int max, final Duration timeout) throws IOException {
474        // this method does what it can to avoid the 'Too many open files' error
475        // based on trial and error and these links:
476        // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
477        // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
478        // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
479        // however, its still not perfect as the JDK support is so poor
480        // (see commons-exec or Ant for a better multi-threaded multi-os solution)
481
482        final List<String> lines = new ArrayList<>(20);
483        Process proc = null;
484        InputStream in = null;
485        OutputStream out = null;
486        InputStream err = null;
487        BufferedReader inr = null;
488        try {
489
490            final Thread monitor = ThreadMonitor.start(timeout);
491
492            proc = openProcess(cmdAttribs);
493            in = proc.getInputStream();
494            out = proc.getOutputStream();
495            err = proc.getErrorStream();
496            // default charset is most likely appropriate here
497            inr = new BufferedReader(new InputStreamReader(in, Charset.defaultCharset()));
498            String line = inr.readLine();
499            while (line != null && lines.size() < max) {
500                line = line.toLowerCase(Locale.ENGLISH).trim();
501                lines.add(line);
502                line = inr.readLine();
503            }
504
505            proc.waitFor();
506
507            ThreadMonitor.stop(monitor);
508
509            if (proc.exitValue() != 0) {
510                // os command problem, throw exception
511                throw new IOException(
512                        "Command line returned OS error code '" + proc.exitValue() +
513                        "' for command " + Arrays.asList(cmdAttribs));
514            }
515            if (lines.isEmpty()) {
516                // unknown problem, throw exception
517                throw new IOException(
518                        "Command line did not return any info " +
519                        "for command " + Arrays.asList(cmdAttribs));
520            }
521
522            inr.close();
523            inr = null;
524
525            in.close();
526            in = null;
527
528            if (out != null) {
529                out.close();
530                out = null;
531            }
532
533            if (err != null) {
534                err.close();
535                err = null;
536            }
537
538            return lines;
539
540        } catch (final InterruptedException ex) {
541            throw new IOException(
542                    "Command line threw an InterruptedException " +
543                    "for command " + Arrays.asList(cmdAttribs) + " timeout=" + timeout, ex);
544        } finally {
545            IOUtils.closeQuietly(in);
546            IOUtils.closeQuietly(out);
547            IOUtils.closeQuietly(err);
548            IOUtils.closeQuietly(inr);
549            if (proc != null) {
550                proc.destroy();
551            }
552        }
553    }
554
555    /**
556     * Opens the process to the operating system.
557     *
558     * @param cmdAttribs  the command line parameters
559     * @return the process
560     * @throws IOException if an error occurs
561     */
562    Process openProcess(final String[] cmdAttribs) throws IOException {
563        return Runtime.getRuntime().exec(cmdAttribs);
564    }
565
566}