    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     * @author Frank W. Zammetti
    043     * @author Stephen Colebourne
    044     * @author Thomas Ledoux
    045     * @author James Urie
    046     * @author Magnus Grimsell
    047     * @author Thomas Ledoux
    048     * @version $Id: FileSystemUtils.java 1003647 2010-10-01 20:53:59Z niallp $
    049     * @since Commons IO 1.1
    050     */
    051    public 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.indexOf("windows") != -1) {
    084                    os = WINDOWS;
    085                } else if (osName.indexOf("linux") != -1 ||
    086                    osName.indexOf("mpe/ix") != -1 ||
    087                    osName.indexOf("freebsd") != -1 ||
    088                    osName.indexOf("irix") != -1 ||
    089                    osName.indexOf("digital unix") != -1 ||
    090                    osName.indexOf("unix") != -1 ||
    091                    osName.indexOf("mac os x") != -1) {
    092                    os = UNIX;
    093                } else if (osName.indexOf("sun os") != -1 ||
    094                    osName.indexOf("sunos") != -1 ||
    095                    osName.indexOf("solaris") != -1) {
    096                    os = POSIX_UNIX;
    097                    dfPath = "/usr/xpg4/bin/df";
    098                } else if (osName.indexOf("hp-ux") != -1 ||
    099                    osName.indexOf("aix") != -1) {
    100                    os = POSIX_UNIX;
    101                } else {
    102                    os = OTHER;
    103                }
    104
    105            } catch (Exception ex) {
    106                os = INIT_PROBLEM;
    107            }
    108            OS = os;
    109            DF = dfPath;
    110        }
    111
    112        /**
    113         * Instances should NOT be constructed in standard programming.
    114         */
    115        public FileSystemUtils() {
    116            super();
    117        }
    118
    119        //-----------------------------------------------------------------------
    120        /**
    121         * Returns the free space on a drive or volume by invoking
    122         * the command line.
    123         * This method does not normalize the result, and typically returns
    124         * bytes on Windows, 512 byte units on OS X and kilobytes on Unix.
    125         * As this is not very useful, this method is deprecated in favour
    126         * of {@link #freeSpaceKb(String)} which returns a result in kilobytes.
    127         * <p>
    128         * Note that some OS's are NOT currently supported, including OS/390,
    129         * OpenVMS.
    130         * <pre>
    131         * FileSystemUtils.freeSpace("C:");       // Windows
    132         * FileSystemUtils.freeSpace("/volume");  // *nix
    133         * </pre>
    134         * The free space is calculated via the command line.
    135         * It uses 'dir /-c' on Windows and 'df' on *nix.
    136         *
    137         * @param path  the path to get free space for, not null, not empty on Unix
    138         * @return the amount of free drive space on the drive or volume
    139         * @throws IllegalArgumentException if the path is invalid
    140         * @throws IllegalStateException if an error occurred in initialisation
    141         * @throws IOException if an error occurs when finding the free space
    142         * @since Commons IO 1.1, enhanced OS support in 1.2 and 1.3
    143         * @deprecated Use freeSpaceKb(String)
    144         *  Deprecated from 1.3, may be removed in 2.0
    145         */
    146        @Deprecated
    147        public static long freeSpace(String path) throws IOException {
    148            return INSTANCE.freeSpaceOS(path, OS, false, -1);
    149        }
    150
    151        //-----------------------------------------------------------------------
    152        /**
    153         * Returns the free space on a drive or volume in kilobytes by invoking
    154         * the command line.
    155         * <pre>
    156         * FileSystemUtils.freeSpaceKb("C:");       // Windows
    157         * FileSystemUtils.freeSpaceKb("/volume");  // *nix
    158         * </pre>
    159         * The free space is calculated via the command line.
    160         * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
    161         * <p>
    162         * In order to work, you must be running Windows, or have a implementation of
    163         * Unix df that supports GNU format when passed -k (or -kP). If you are going
    164         * to rely on this code, please check that it works on your OS by running
    165         * some simple tests to compare the command line with the output from this class.
    166         * If your operating system isn't supported, please raise a JIRA call detailing
    167         * the exact result from df -k and as much other detail as possible, thanks.
    168         *
    169         * @param path  the path to get free space for, not null, not empty on Unix
    170         * @return the amount of free drive space on the drive or volume in kilobytes
    171         * @throws IllegalArgumentException if the path is invalid
    172         * @throws IllegalStateException if an error occurred in initialisation
    173         * @throws IOException if an error occurs when finding the free space
    174         * @since Commons IO 1.2, enhanced OS support in 1.3
    175         */
    176        public static long freeSpaceKb(String path) throws IOException {
    177            return freeSpaceKb(path, -1);
    178        }
    179        /**
    180         * Returns the free space on a drive or volume in kilobytes by invoking
    181         * the command line.
    182         * <pre>
    183         * FileSystemUtils.freeSpaceKb("C:");       // Windows
    184         * FileSystemUtils.freeSpaceKb("/volume");  // *nix
    185         * </pre>
    186         * The free space is calculated via the command line.
    187         * It uses 'dir /-c' on Windows, 'df -kP' on AIX/HP-UX and 'df -k' on other Unix.
    188         * <p>
    189         * In order to work, you must be running Windows, or have a implementation of
    190         * Unix df that supports GNU format when passed -k (or -kP). If you are going
    191         * to rely on this code, please check that it works on your OS by running
    192         * some simple tests to compare the command line with the output from this class.
    193         * If your operating system isn't supported, please raise a JIRA call detailing
    194         * the exact result from df -k and as much other detail as possible, thanks.
    195         *
    196         * @param path  the path to get free space for, not null, not empty on Unix
    197         * @param timeout The timout amount in milliseconds or no timeout if the value
    198         *  is zero or less
    199         * @return the amount of free drive space on the drive or volume in kilobytes
    200         * @throws IllegalArgumentException if the path is invalid
    201         * @throws IllegalStateException if an error occurred in initialisation
    202         * @throws IOException if an error occurs when finding the free space
    203         * @since Commons IO 2.0
    204         */
    205        public static long freeSpaceKb(String path, long timeout) throws IOException {
    206            return INSTANCE.freeSpaceOS(path, OS, true, timeout);
    207        }
    208
    209        /**
    210         * Returns the disk size of the volume which holds the working directory.
    211         * <p>
    212         * Identical to:
    213         * <pre>
    214         * freeSpaceKb(new File(".").getAbsolutePath())
    215         * </pre>
    216         * @return the amount of free drive space on the drive or volume in kilobytes
    217         * @throws IllegalStateException if an error occurred in initialisation
    218         * @throws IOException if an error occurs when finding the free space
    219         * @since Commons IO 2.0
    220         */
    221        public static long freeSpaceKb() throws IOException {
    222            return freeSpaceKb(-1);
    223        }
    224
    225        /**
    226         * Returns the disk size of the volume which holds the working directory.
    227         * <p>
    228         * Identical to:
    229         * <pre>
    230         * freeSpaceKb(new File(".").getAbsolutePath())
    231         * </pre>
    232         * @param timeout The timout amount in milliseconds or no timeout if the value
    233         *  is zero or less
    234         * @return the amount of free drive space on the drive or volume in kilobytes
    235         * @throws IllegalStateException if an error occurred in initialisation
    236         * @throws IOException if an error occurs when finding the free space
    237         * @since Commons IO 2.0
    238         */
    239        public static long freeSpaceKb(long timeout) throws IOException {
    240            return freeSpaceKb(new File(".").getAbsolutePath(), timeout);
    241        }
    242
    243        //-----------------------------------------------------------------------
    244        /**
    245         * Returns the free space on a drive or volume in a cross-platform manner.
    246         * Note that some OS's are NOT currently supported, including OS/390.
    247         * <pre>
    248         * FileSystemUtils.freeSpace("C:");  // Windows
    249         * FileSystemUtils.freeSpace("/volume");  // *nix
    250         * </pre>
    251         * The free space is calculated via the command line.
    252         * It uses 'dir /-c' on Windows and 'df' on *nix.
    253         *
    254         * @param path  the path to get free space for, not null, not empty on Unix
    255         * @param os  the operating system code
    256         * @param kb  whether to normalize to kilobytes
    257         * @param timeout The timout amount in milliseconds or no timeout if the value
    258         *  is zero or less
    259         * @return the amount of free drive space on the drive or volume
    260         * @throws IllegalArgumentException if the path is invalid
    261         * @throws IllegalStateException if an error occurred in initialisation
    262         * @throws IOException if an error occurs when finding the free space
    263         */
    264        long freeSpaceOS(String path, int os, boolean kb, long timeout) throws IOException {
    265            if (path == null) {
    266                throw new IllegalArgumentException("Path must not be empty");
    267            }
    268            switch (os) {
    269                case WINDOWS:
    270                    return (kb ? freeSpaceWindows(path, timeout) / 1024 : freeSpaceWindows(path, timeout));
    271                case UNIX:
    272                    return freeSpaceUnix(path, kb, false, timeout);
    273                case POSIX_UNIX:
    274                    return freeSpaceUnix(path, kb, true, timeout);
    275                case OTHER:
    276                    throw new IllegalStateException("Unsupported operating system");
    277                default:
    278                    throw new IllegalStateException(
    279                      "Exception caught when determining operating system");
    280            }
    281        }
    282
    283        //-----------------------------------------------------------------------
    284        /**
    285         * Find free space on the Windows platform using the 'dir' command.
    286         *
    287         * @param path  the path to get free space for, including the colon
    288         * @param timeout The timout amount in milliseconds or no timeout if the value
    289         *  is zero or less
    290         * @return the amount of free drive space on the drive
    291         * @throws IOException if an error occurs
    292         */
    293        long freeSpaceWindows(String path, long timeout) throws IOException {
    294            path = FilenameUtils.normalize(path, false);
    295            if (path.length() > 0 && path.charAt(0) != '"') {
    296                path = "\"" + path + "\"";
    297            }
    298
    299            // build and run the 'dir' command
    300            String[] cmdAttribs = new String[] {"cmd.exe", "/C", "dir /-c " + path};
    301
    302            // read in the output of the command to an ArrayList
    303            List<String> lines = performCommand(cmdAttribs, Integer.MAX_VALUE, timeout);
    304
    305            // now iterate over the lines we just read and find the LAST
    306            // non-empty line (the free space bytes should be in the last element
    307            // of the ArrayList anyway, but this will ensure it works even if it's
    308            // not, still assuming it is on the last non-blank line)
    309            for (int i = lines.size() - 1; i >= 0; i--) {
    310                String line = lines.get(i);
    311                if (line.length() > 0) {
    312                    return parseDir(line, path);
    313                }
    314            }
    315            // all lines are blank
    316            throw new IOException(
    317                    "Command line 'dir /-c' did not return any info " +
    318                    "for path '" + path + "'");
    319        }
    320
    321        /**
    322         * Parses the Windows dir response last line
    323         *
    324         * @param line  the line to parse
    325         * @param path  the path that was sent
    326         * @return the number of bytes
    327         * @throws IOException if an error occurs
    328         */
    329        long parseDir(String line, String path) throws IOException {
    330            // read from the end of the line to find the last numeric
    331            // character on the line, then continue until we find the first
    332            // non-numeric character, and everything between that and the last
    333            // numeric character inclusive is our free space bytes count
    334            int bytesStart = 0;
    335            int bytesEnd = 0;
    336            int j = line.length() - 1;
    337            innerLoop1: while (j >= 0) {
    338                char c = line.charAt(j);
    339                if (Character.isDigit(c)) {
    340                  // found the last numeric character, this is the end of
    341                  // the free space bytes count
    342                  bytesEnd = j + 1;
    343                  break innerLoop1;
    344                }
    345                j--;
    346            }
    347            innerLoop2: while (j >= 0) {
    348                char c = line.charAt(j);
    349                if (!Character.isDigit(c) && c != ',' && c != '.') {
    350                  // found the next non-numeric character, this is the
    351                  // beginning of the free space bytes count
    352                  bytesStart = j + 1;
    353                  break innerLoop2;
    354                }
    355                j--;
    356            }
    357            if (j < 0) {
    358                throw new IOException(
    359                        "Command line 'dir /-c' did not return valid info " +
    360                        "for path '" + path + "'");
    361            }
    362
    363            // remove commas and dots in the bytes count
    364            StringBuilder buf = new StringBuilder(line.substring(bytesStart, bytesEnd));
    365            for (int k = 0; k < buf.length(); k++) {
    366                if (buf.charAt(k) == ',' || buf.charAt(k) == '.') {
    367                    buf.deleteCharAt(k--);
    368                }
    369            }
    370            return parseBytes(buf.toString(), path);
    371        }
    372
    373        //-----------------------------------------------------------------------
    374        /**
    375         * Find free space on the *nix platform using the 'df' command.
    376         *
    377         * @param path  the path to get free space for
    378         * @param kb  whether to normalize to kilobytes
    379         * @param posix  whether to use the posix standard format flag
    380         * @param timeout The timout amount in milliseconds or no timeout if the value
    381         *  is zero or less
    382         * @return the amount of free drive space on the volume
    383         * @throws IOException if an error occurs
    384         */
    385        long freeSpaceUnix(String path, boolean kb, boolean posix, long timeout) throws IOException {
    386            if (path.length() == 0) {
    387                throw new IllegalArgumentException("Path must not be empty");
    388            }
    389
    390            // build and run the 'dir' command
    391            String flags = "-";
    392            if (kb) {
    393                flags += "k";
    394            }
    395            if (posix) {
    396                flags += "P";
    397            }
    398            String[] cmdAttribs =
    399                (flags.length() > 1 ? new String[] {DF, flags, path} : new String[] {DF, path});
    400
    401            // perform the command, asking for up to 3 lines (header, interesting, overflow)
    402            List<String> lines = performCommand(cmdAttribs, 3, timeout);
    403            if (lines.size() < 2) {
    404                // unknown problem, throw exception
    405                throw new IOException(
    406                        "Command line '" + DF + "' did not return info as expected " +
    407                        "for path '" + path + "'- response was " + lines);
    408            }
    409            String line2 = lines.get(1); // the line we're interested in
    410
    411            // Now, we tokenize the string. The fourth element is what we want.
    412            StringTokenizer tok = new StringTokenizer(line2, " ");
    413            if (tok.countTokens() < 4) {
    414                // could be long Filesystem, thus data on third line
    415                if (tok.countTokens() == 1 && lines.size() >= 3) {
    416                    String line3 = lines.get(2); // the line may be interested in
    417                    tok = new StringTokenizer(line3, " ");
    418                } else {
    419                    throw new IOException(
    420                            "Command line '" + DF + "' did not return data as expected " +
    421                            "for path '" + path + "'- check path is valid");
    422                }
    423            } else {
    424                tok.nextToken(); // Ignore Filesystem
    425            }
    426            tok.nextToken(); // Ignore 1K-blocks
    427            tok.nextToken(); // Ignore Used
    428            String freeSpace = tok.nextToken();
    429            return parseBytes(freeSpace, path);
    430        }
    431
    432        //-----------------------------------------------------------------------
    433        /**
    434         * Parses the bytes from a string.
    435         *
    436         * @param freeSpace  the free space string
    437         * @param path  the path
    438         * @return the number of bytes
    439         * @throws IOException if an error occurs
    440         */
    441        long parseBytes(String freeSpace, String path) throws IOException {
    442            try {
    443                long bytes = Long.parseLong(freeSpace);
    444                if (bytes < 0) {
    445                    throw new IOException(
    446                            "Command line '" + DF + "' did not find free space in response " +
    447                            "for path '" + path + "'- check path is valid");
    448                }
    449                return bytes;
    450
    451            } catch (NumberFormatException ex) {
    452                throw new IOExceptionWithCause(
    453                        "Command line '" + DF + "' did not return numeric data as expected " +
    454                        "for path '" + path + "'- check path is valid", ex);
    455            }
    456        }
    457
    458        //-----------------------------------------------------------------------
    459        /**
    460         * Performs the os command.
    461         *
    462         * @param cmdAttribs  the command line parameters
    463         * @param max The maximum limit for the lines returned
    464         * @param timeout The timout amount in milliseconds or no timeout if the value
    465         *  is zero or less
    466         * @return the parsed data
    467         * @throws IOException if an error occurs
    468         */
    469        List<String> performCommand(String[] cmdAttribs, int max, long timeout) throws IOException {
    470            // this method does what it can to avoid the 'Too many open files' error
    471            // based on trial and error and these links:
    472            // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4784692
    473            // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4801027
    474            // http://forum.java.sun.com/thread.jspa?threadID=533029&messageID=2572018
    475            // however, its still not perfect as the JDK support is so poor
    476            // (see commond-exec or ant for a better multi-threaded multi-os solution)
    477
    478            List<String> lines = new ArrayList<String>(20);
    479            Process proc = null;
    480            InputStream in = null;
    481            OutputStream out = null;
    482            InputStream err = null;
    483            BufferedReader inr = null;
    484            try {
    485
    486                Thread monitor = ThreadMonitor.start(timeout);
    487
    488                proc = openProcess(cmdAttribs);
    489                in = proc.getInputStream();
    490                out = proc.getOutputStream();
    491                err = proc.getErrorStream();
    492                inr = new BufferedReader(new InputStreamReader(in));
    493                String line = inr.readLine();
    494                while (line != null && lines.size() < max) {
    495                    line = line.toLowerCase(Locale.ENGLISH).trim();
    496                    lines.add(line);
    497                    line = inr.readLine();
    498                }
    499
    500                proc.waitFor();
    501
    502                ThreadMonitor.stop(monitor);
    503
    504                if (proc.exitValue() != 0) {
    505                    // os command problem, throw exception
    506                    throw new IOException(
    507                            "Command line returned OS error code '" + proc.exitValue() +
    508                            "' for command " + Arrays.asList(cmdAttribs));
    509                }
    510                if (lines.size() == 0) {
    511                    // unknown problem, throw exception
    512                    throw new IOException(
    513                            "Command line did not return any info " +
    514                            "for command " + Arrays.asList(cmdAttribs));
    515                }
    516                return lines;
    517
    518            } catch (InterruptedException ex) {
    519                throw new IOExceptionWithCause(
    520                        "Command line threw an InterruptedException " +
    521                        "for command " + Arrays.asList(cmdAttribs) + " timeout=" + timeout, ex);
    522            } finally {
    523                IOUtils.closeQuietly(in);
    524                IOUtils.closeQuietly(out);
    525                IOUtils.closeQuietly(err);
    526                IOUtils.closeQuietly(inr);
    527                if (proc != null) {
    528                    proc.destroy();
    529                }
    530            }
    531        }
    532
    533        /**
    534         * Opens the process to the operating system.
    535         *
    536         * @param cmdAttribs  the command line parameters
    537         * @return the process
    538         * @throws IOException if an error occurs
    539         */
    540        Process openProcess(String[] cmdAttribs) throws IOException {
    541            return Runtime.getRuntime().exec(cmdAttribs);
    542        }
    543
    544    }