diff options
Diffstat (limited to 'org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java')
| -rw-r--r-- | org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java | 927 |
1 files changed, 801 insertions, 126 deletions
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java index 1e58245ea7..39c67f1b86 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java @@ -1,64 +1,64 @@ /* * Copyright (C) 2010, Google Inc. * Copyright (C) 2010, Matthias Sohn <matthias.sohn@sap.com> - * Copyright (C) 2010, Jens Baumgart <jens.baumgart@sap.com> - * and other copyright owners as documented in the project's IP log. + * Copyright (C) 2010, Jens Baumgart <jens.baumgart@sap.com> and others * - * This program and the accompanying materials are made available - * under the terms of the Eclipse Distribution License v1.0 which - * accompanies this distribution, is reproduced below, and is - * available at http://www.eclipse.org/org/documents/edl-v10.php + * This program and the accompanying materials are made available under the + * terms of the Eclipse Distribution License v. 1.0 which is available at + * https://www.eclipse.org/org/documents/edl-v10.php. * - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or - * without modification, are permitted provided that the following - * conditions are met: - * - * - Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - * - Redistributions in binary form must reproduce the above - * copyright notice, this list of conditions and the following - * disclaimer in the documentation and/or other materials provided - * with the distribution. - * - * - Neither the name of the Eclipse Foundation, Inc. nor the - * names of its contributors may be used to endorse or promote - * products derived from this software without specific prior - * written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND - * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, - * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR - * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; - * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER - * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) - * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF - * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * SPDX-License-Identifier: BSD-3-Clause */ package org.eclipse.jgit.util; +import static java.nio.charset.StandardCharsets.UTF_8; + import java.io.File; +import java.io.FileNotFoundException; import java.io.IOException; -import java.nio.channels.FileLock; +import java.io.InterruptedIOException; +import java.nio.channels.FileChannel; +import java.nio.file.AtomicMoveNotSupportedException; +import java.nio.file.CopyOption; +import java.nio.file.DirectoryNotEmptyException; +import java.nio.file.Files; +import java.nio.file.InvalidPathException; +import java.nio.file.LinkOption; +import java.nio.file.NoSuchFileException; +import java.nio.file.Path; +import java.nio.file.StandardCopyOption; +import java.nio.file.StandardOpenOption; +import java.nio.file.attribute.BasicFileAttributeView; +import java.nio.file.attribute.BasicFileAttributes; +import java.nio.file.attribute.FileTime; +import java.nio.file.attribute.PosixFileAttributeView; +import java.nio.file.attribute.PosixFileAttributes; +import java.nio.file.attribute.PosixFilePermission; import java.text.MessageFormat; +import java.text.Normalizer; +import java.text.Normalizer.Form; +import java.time.Instant; import java.util.ArrayList; import java.util.List; +import java.util.Locale; +import java.util.Random; import java.util.regex.Pattern; +import java.util.stream.Stream; import org.eclipse.jgit.internal.JGitText; +import org.eclipse.jgit.lib.Constants; +import org.eclipse.jgit.util.FS.Attributes; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; /** * File Utilities */ public class FileUtils { + private static final Logger LOG = LoggerFactory.getLogger(FileUtils.class); + + private static final Random RNG = new Random(); /** * Option to delete given {@code File} @@ -95,17 +95,36 @@ public class FileUtils { public static final int EMPTY_DIRECTORIES_ONLY = 16; /** + * Safe conversion from {@link java.io.File} to {@link java.nio.file.Path}. + * + * @param f + * {@code File} to be converted to {@code Path} + * @return the path represented by the file + * @throws java.io.IOException + * in case the path represented by the file is not valid ( + * {@link java.nio.file.InvalidPathException}) + * @since 4.10 + */ + public static Path toPath(File f) throws IOException { + try { + return f.toPath(); + } catch (InvalidPathException ex) { + throw new IOException(ex); + } + } + + /** * Delete file or empty folder * * @param f * {@code File} to be deleted - * @throws IOException + * @throws java.io.IOException * if deletion of {@code f} fails. This may occur if {@code f} * didn't exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to delete the same file. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to delete the same file. */ - public static void delete(final File f) throws IOException { + public static void delete(File f) throws IOException { delete(f, NONE); } @@ -119,14 +138,14 @@ public class FileUtils { * a subtree, {@code RETRY} to retry when deletion failed. * Retrying may help if the underlying file system doesn't allow * deletion of files being read by another thread. - * @throws IOException + * @throws java.io.IOException * if deletion of {@code f} fails. This may occur if {@code f} * didn't exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to delete the same file. This - * exception is not thrown when IGNORE_ERRORS is set. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to delete the same file. + * This exception is not thrown when IGNORE_ERRORS is set. */ - public static void delete(final File f, int options) throws IOException { + public static void delete(File f, int options) throws IOException { FS fs = FS.DETECTED; if ((options & SKIP_MISSING) != 0 && !fs.exists(f)) return; @@ -134,8 +153,8 @@ public class FileUtils { if ((options & RECURSIVE) != 0 && fs.isDirectory(f)) { final File[] items = f.listFiles(); if (items != null) { - List<File> files = new ArrayList<File>(); - List<File> dirs = new ArrayList<File>(); + List<File> files = new ArrayList<>(); + List<File> dirs = new ArrayList<>(); for (File c : items) if (c.isFile()) files.add(c); @@ -155,31 +174,64 @@ public class FileUtils { if ((options & EMPTY_DIRECTORIES_ONLY) != 0) { if (f.isDirectory()) { delete = true; - } else { - if ((options & IGNORE_ERRORS) == 0) - throw new IOException(MessageFormat.format( - JGitText.get().deleteFileFailed, - f.getAbsolutePath())); + } else if ((options & IGNORE_ERRORS) == 0) { + throw new IOException(MessageFormat.format( + JGitText.get().deleteFileFailed, f.getAbsolutePath())); } } else { delete = true; } - if (delete && !f.delete()) { - if ((options & RETRY) != 0 && fs.exists(f)) { + if (delete) { + IOException t = null; + Path p = f.toPath(); + boolean tryAgain; + do { + tryAgain = false; + try { + Files.delete(p); + return; + } catch (NoSuchFileException | FileNotFoundException e) { + handleDeleteException(f, e, options, + SKIP_MISSING | IGNORE_ERRORS); + return; + } catch (DirectoryNotEmptyException e) { + handleDeleteException(f, e, options, IGNORE_ERRORS); + return; + } catch (IOException e) { + if (!f.canWrite()) { + tryAgain = f.setWritable(true); + } + if (!tryAgain) { + t = e; + } + } + } while (tryAgain); + + if ((options & RETRY) != 0) { for (int i = 1; i < 10; i++) { try { Thread.sleep(100); - } catch (InterruptedException e) { + } catch (InterruptedException ex) { // ignore } - if (f.delete()) + try { + Files.deleteIfExists(p); return; + } catch (IOException e) { + t = e; + } } } - if ((options & IGNORE_ERRORS) == 0) - throw new IOException(MessageFormat.format( - JGitText.get().deleteFileFailed, f.getAbsolutePath())); + handleDeleteException(f, t, options, IGNORE_ERRORS); + } + } + + private static void handleDeleteException(File f, IOException e, + int allOptions, int checkOptions) throws IOException { + if (e != null && (allOptions & checkOptions) == 0) { + throw new IOException(MessageFormat.format( + JGitText.get().deleteFileFailed, f.getAbsolutePath()), e); } } @@ -201,36 +253,85 @@ public class FileUtils { * the old {@code File} * @param dst * the new {@code File} - * @throws IOException + * @throws java.io.IOException * if the rename has failed * @since 3.0 */ - public static void rename(final File src, final File dst) + public static void rename(File src, File dst) throws IOException { + rename(src, dst, StandardCopyOption.REPLACE_EXISTING); + } + + /** + * Rename a file or folder using the passed + * {@link java.nio.file.CopyOption}s. If the rename fails and if we are + * running on a filesystem where it makes sense to repeat a failing rename + * then repeat the rename operation up to 9 times with 100ms sleep time + * between two calls. Furthermore if the destination exists and is a + * directory hierarchy with only directories in it, the whole directory + * hierarchy will be deleted. If the target represents a non-empty directory + * structure, empty subdirectories within that structure may or may not be + * deleted even if the method fails. Furthermore if the destination exists + * and is a file then the file will be replaced if + * {@link java.nio.file.StandardCopyOption#REPLACE_EXISTING} has been set. + * If {@link java.nio.file.StandardCopyOption#ATOMIC_MOVE} has been set the + * rename will be done atomically or fail with an + * {@link java.nio.file.AtomicMoveNotSupportedException} + * + * @param src + * the old file + * @param dst + * the new file + * @param options + * options to pass to + * {@link java.nio.file.Files#move(java.nio.file.Path, java.nio.file.Path, CopyOption...)} + * @throws java.nio.file.AtomicMoveNotSupportedException + * if file cannot be moved as an atomic file system operation + * @throws java.io.IOException + * if an IO error occurred + * @since 4.1 + */ + public static void rename(final File src, final File dst, + CopyOption... options) + throws AtomicMoveNotSupportedException, IOException { int attempts = FS.DETECTED.retryFailedLockFileCommit() ? 10 : 1; + IOException finalError = null; while (--attempts >= 0) { - if (src.renameTo(dst)) - return; try { - if (!dst.delete()) - delete(dst, EMPTY_DIRECTORIES_ONLY | RECURSIVE); - // On *nix there is no try, you do or do not - if (src.renameTo(dst)) - return; + Files.move(toPath(src), toPath(dst), options); + return; + } catch (AtomicMoveNotSupportedException e) { + throw e; } catch (IOException e) { - // ignore and continue retry + if (attempts == 0) { + // Only delete on the last attempt. + try { + if (!dst.delete()) { + delete(dst, EMPTY_DIRECTORIES_ONLY | RECURSIVE); + } + // On *nix there is no try, you do or do not + Files.move(toPath(src), toPath(dst), options); + return; + } catch (IOException e2) { + e2.addSuppressed(e); + finalError = e2; + } + } } - try { - Thread.sleep(100); - } catch (InterruptedException e) { - throw new IOException(MessageFormat.format( - JGitText.get().renameFileFailed, src.getAbsolutePath(), - dst.getAbsolutePath())); + if (attempts > 0) { + try { + Thread.sleep(100); + } catch (InterruptedException e) { + throw new IOException(MessageFormat.format( + JGitText.get().renameFileFailed, + src.getAbsolutePath(), dst.getAbsolutePath()), e); + } } } - throw new IOException(MessageFormat.format( - JGitText.get().renameFileFailed, src.getAbsolutePath(), - dst.getAbsolutePath())); + throw new IOException( + MessageFormat.format(JGitText.get().renameFileFailed, + src.getAbsolutePath(), dst.getAbsolutePath()), + finalError); } /** @@ -238,13 +339,14 @@ public class FileUtils { * * @param d * directory to be created - * @throws IOException + * @throws java.io.IOException * if creation of {@code d} fails. This may occur if {@code d} * did exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to create the same directory. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to create the same + * directory. */ - public static void mkdir(final File d) + public static void mkdir(File d) throws IOException { mkdir(d, false); } @@ -257,13 +359,14 @@ public class FileUtils { * @param skipExisting * if {@code true} skip creation of the given directory if it * already exists in the file system - * @throws IOException + * @throws java.io.IOException * if creation of {@code d} fails. This may occur if {@code d} * did exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to create the same directory. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to create the same + * directory. */ - public static void mkdir(final File d, boolean skipExisting) + public static void mkdir(File d, boolean skipExisting) throws IOException { if (!d.mkdir()) { if (skipExisting && d.isDirectory()) @@ -281,13 +384,14 @@ public class FileUtils { * * @param d * directory to be created - * @throws IOException + * @throws java.io.IOException * if creation of {@code d} fails. This may occur if {@code d} * did exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to create the same directory. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to create the same + * directory. */ - public static void mkdirs(final File d) throws IOException { + public static void mkdirs(File d) throws IOException { mkdirs(d, false); } @@ -302,13 +406,14 @@ public class FileUtils { * @param skipExisting * if {@code true} skip creation of the given directory if it * already exists in the file system - * @throws IOException + * @throws java.io.IOException * if creation of {@code d} fails. This may occur if {@code d} * did exist when the method was called. This can therefore - * cause IOExceptions during race conditions when multiple - * concurrent threads all try to create the same directory. + * cause java.io.IOExceptions during race conditions when + * multiple concurrent threads all try to create the same + * directory. */ - public static void mkdirs(final File d, boolean skipExisting) + public static void mkdirs(File d, boolean skipExisting) throws IOException { if (!d.mkdirs()) { if (skipExisting && d.isDirectory()) @@ -326,12 +431,12 @@ public class FileUtils { * filesystem activities that might affect the file. * <p> * Note: this method should not be used for file-locking, as the resulting - * protocol cannot be made to work reliably. The {@link FileLock} facility - * should be used instead. + * protocol cannot be made to work reliably. The + * {@link java.nio.channels.FileLock} facility should be used instead. * * @param f * the file to be created - * @throws IOException + * @throws java.io.IOException * if the named file already exists or if an I/O error occurred */ public static void createNewFile(File f) throws IOException { @@ -344,35 +449,67 @@ public class FileUtils { * Create a symbolic link * * @param path + * the path of the symbolic link to create * @param target - * @throws IOException - * @since 3.0 + * the target of the symbolic link + * @return the path to the symbolic link + * @throws java.io.IOException + * if an IO error occurred + * @since 4.2 */ - public static void createSymLink(File path, String target) + public static Path createSymLink(File path, String target) throws IOException { - FS.DETECTED.createSymLink(path, target); + Path nioPath = toPath(path); + if (Files.exists(nioPath, LinkOption.NOFOLLOW_LINKS)) { + BasicFileAttributes attrs = Files.readAttributes(nioPath, + BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); + if (attrs.isRegularFile() || attrs.isSymbolicLink()) { + delete(path); + } else { + delete(path, EMPTY_DIRECTORIES_ONLY | RECURSIVE); + } + } + if (SystemReader.getInstance().isWindows()) { + target = target.replace('/', '\\'); + } + Path nioTarget = toPath(new File(target)); + return Files.createSymbolicLink(nioPath, nioTarget); } /** + * Read target path of the symlink. + * * @param path - * @return the target of the symbolic link, or null if it is not a symbolic - * link - * @throws IOException + * a {@link java.io.File} object. + * @return target path of the symlink, or null if it is not a symbolic link + * @throws java.io.IOException + * if an IO error occurred * @since 3.0 */ public static String readSymLink(File path) throws IOException { - return FS.DETECTED.readSymLink(path); + Path nioPath = toPath(path); + Path target = Files.readSymbolicLink(nioPath); + String targetString = target.toString(); + if (SystemReader.getInstance().isWindows()) { + targetString = targetString.replace('\\', '/'); + } else if (SystemReader.getInstance().isMacOS()) { + targetString = Normalizer.normalize(targetString, Form.NFC); + } + return targetString; } /** * Create a temporary directory. * * @param prefix + * prefix string * @param suffix + * suffix string * @param dir * The parent dir, can be null to use system default temp dir. * @return the temp dir created. - * @throws IOException + * @throws java.io.IOException + * if an IO error occurred * @since 3.4 */ public static File createTempDir(String prefix, String suffix, File dir) @@ -390,9 +527,48 @@ public class FileUtils { } /** - * This will try and make a given path relative to another. + * Expresses <code>other</code> as a relative file path from + * <code>base</code>. File-separator and case sensitivity are based on the + * current file system. + * + * See also + * {@link org.eclipse.jgit.util.FileUtils#relativizePath(String, String, String, boolean)}. + * + * @param base + * Base path + * @param other + * Destination path + * @return Relative path from <code>base</code> to <code>other</code> + * @since 4.8 + */ + public static String relativizeNativePath(String base, String other) { + return FS.DETECTED.relativize(base, other); + } + + /** + * Expresses <code>other</code> as a relative file path from + * <code>base</code>. File-separator and case sensitivity are based on Git's + * internal representation of files (which matches Unix). + * + * See also + * {@link org.eclipse.jgit.util.FileUtils#relativizePath(String, String, String, boolean)}. + * + * @param base + * Base path + * @param other + * Destination path + * @return Relative path from <code>base</code> to <code>other</code> + * @since 4.8 + */ + public static String relativizeGitPath(String base, String other) { + return relativizePath(base, other, "/", false); //$NON-NLS-1$ + } + + + /** + * Expresses <code>other</code> as a relative file path from <code>base</code> * <p> - * For example, if this is called with the two following paths : + * For example, if called with the two following paths : * * <pre> * <code>base = "c:\\Users\\jdoe\\eclipse\\git\\project"</code> @@ -400,10 +576,7 @@ public class FileUtils { * </pre> * * This will return "..\\another_project\\pom.xml". - * </p> - * <p> - * This method uses {@link File#separator} to split the paths into segments. - * </p> + * * <p> * <b>Note</b> that this will return the empty String if <code>base</code> * and <code>other</code> are equal. @@ -415,29 +588,32 @@ public class FileUtils { * folder and not a file. * @param other * The path that will be made relative to <code>base</code>. + * @param dirSeparator + * A string that separates components of the path. In practice, this is "/" or "\\". + * @param caseSensitive + * Whether to consider differently-cased directory names as distinct * @return A relative path that, when resolved against <code>base</code>, * will yield the original <code>other</code>. - * @since 3.7 + * @since 4.8 */ - public static String relativize(String base, String other) { + public static String relativizePath(String base, String other, String dirSeparator, boolean caseSensitive) { if (base.equals(other)) return ""; //$NON-NLS-1$ - final boolean ignoreCase = !FS.DETECTED.isCaseSensitive(); - final String[] baseSegments = base.split(Pattern.quote(File.separator)); + final String[] baseSegments = base.split(Pattern.quote(dirSeparator)); final String[] otherSegments = other.split(Pattern - .quote(File.separator)); + .quote(dirSeparator)); int commonPrefix = 0; while (commonPrefix < baseSegments.length && commonPrefix < otherSegments.length) { - if (ignoreCase + if (caseSensitive && baseSegments[commonPrefix] - .equalsIgnoreCase(otherSegments[commonPrefix])) + .equals(otherSegments[commonPrefix])) commonPrefix++; - else if (!ignoreCase + else if (!caseSensitive && baseSegments[commonPrefix] - .equals(otherSegments[commonPrefix])) + .equalsIgnoreCase(otherSegments[commonPrefix])) commonPrefix++; else break; @@ -445,12 +621,511 @@ public class FileUtils { final StringBuilder builder = new StringBuilder(); for (int i = commonPrefix; i < baseSegments.length; i++) - builder.append("..").append(File.separator); //$NON-NLS-1$ + builder.append("..").append(dirSeparator); //$NON-NLS-1$ for (int i = commonPrefix; i < otherSegments.length; i++) { builder.append(otherSegments[i]); if (i < otherSegments.length - 1) - builder.append(File.separator); + builder.append(dirSeparator); } return builder.toString(); } + + /** + * Determine if an IOException is a stale NFS file handle + * + * @param ioe + * an {@link java.io.IOException} object. + * @return a boolean true if the IOException is a stale NFS file handle + * @since 4.1 + */ + public static boolean isStaleFileHandle(IOException ioe) { + String msg = ioe.getMessage(); + return msg != null + && msg.toLowerCase(Locale.ROOT) + .matches("stale .*file .*handle"); //$NON-NLS-1$ + } + + /** + * Determine if a throwable or a cause in its causal chain is a stale NFS + * file handle + * + * @param throwable + * a {@link java.lang.Throwable} object. + * @return a boolean true if the throwable or a cause in its causal chain is + * a stale NFS file handle + * @since 4.7 + */ + public static boolean isStaleFileHandleInCausalChain(Throwable throwable) { + while (throwable != null) { + if (throwable instanceof IOException + && isStaleFileHandle((IOException) throwable)) { + return true; + } + throwable = throwable.getCause(); + } + return false; + } + + /** + * Like a {@link java.util.function.Function} but throwing an + * {@link Exception}. + * + * @param <A> + * input type + * @param <B> + * output type + * @since 6.2 + */ + @FunctionalInterface + public interface IOFunction<A, B> { + + /** + * Performs the function. + * + * @param t + * input to operate on + * @return the output + * @throws Exception + * if a problem occurs + */ + B apply(A t) throws Exception; + } + + private static void backOff(long delay, IOException cause) + throws IOException { + try { + Thread.sleep(delay); + } catch (InterruptedException e) { + IOException interruption = new InterruptedIOException(); + interruption.initCause(e); + interruption.addSuppressed(cause); + Thread.currentThread().interrupt(); // Re-set flag + throw interruption; + } + } + + /** + * Invokes the given {@link IOFunction}, performing a limited number of + * re-tries if exceptions occur that indicate either a stale NFS file handle + * or that indicate that the file may be written concurrently. + * + * @param <T> + * result type + * @param file + * to read + * @param reader + * for reading the file and creating an instance of {@code T} + * @return the result of the {@code reader}, or {@code null} if the file + * does not exist + * @throws Exception + * if a problem occurs + * @since 6.2 + */ + public static <T> T readWithRetries(File file, + IOFunction<File, ? extends T> reader) + throws Exception { + int maxStaleRetries = 5; + int retries = 0; + long backoff = 50; + while (true) { + try { + try { + return reader.apply(file); + } catch (IOException e) { + if (FileUtils.isStaleFileHandleInCausalChain(e) + && retries < maxStaleRetries) { + if (LOG.isDebugEnabled()) { + LOG.debug(MessageFormat.format( + JGitText.get().packedRefsHandleIsStale, + Integer.valueOf(retries)), e); + } + retries++; + continue; + } + throw e; + } + } catch (FileNotFoundException noFile) { + if (!file.isFile()) { + return null; + } + // Probably Windows and some other thread is writing the file + // concurrently. + if (backoff > 1000) { + throw noFile; + } + backOff(backoff, noFile); + backoff *= 2; // 50, 100, 200, 400, 800 ms + } + } + } + + /** + * Check if file is a symlink + * + * @param file + * the file to be checked if it is a symbolic link + * @return {@code true} if the passed file is a symbolic link + */ + static boolean isSymlink(File file) { + return Files.isSymbolicLink(file.toPath()); + } + + /** + * Get last modified timestamp of a file + * + * @param path + * file path + * @return lastModified attribute for given file, not following symbolic + * links + */ + static Instant lastModifiedInstant(Path path) { + try { + return Files.getLastModifiedTime(path, LinkOption.NOFOLLOW_LINKS) + .toInstant(); + } catch (NoSuchFileException e) { + LOG.debug( + "Cannot read lastModifiedInstant since path {} does not exist", //$NON-NLS-1$ + path); + return Instant.EPOCH; + } catch (IOException e) { + LOG.error(MessageFormat + .format(JGitText.get().readLastModifiedFailed, path), e); + return Instant.ofEpochMilli(path.toFile().lastModified()); + } + } + + /** + * Return all the attributes of a file, without following symbolic links. + * + * @param file + * the file + * @return {@link BasicFileAttributes} of the file + * @throws IOException + * in case of any I/O errors accessing the file + * + * @since 4.5.6 + */ + static BasicFileAttributes fileAttributes(File file) throws IOException { + return Files.readAttributes(file.toPath(), BasicFileAttributes.class, LinkOption.NOFOLLOW_LINKS); + } + + /** + * Set the last modified time of a file system object. + * + * @param path + * file path + * @param time + * last modified timestamp of the file + * @throws IOException + * if an IO error occurred + */ + static void setLastModified(Path path, Instant time) + throws IOException { + Files.setLastModifiedTime(path, FileTime.from(time)); + } + + /** + * Whether the file exists + * + * @param file + * the file + * @return {@code true} if the given file exists, not following symbolic + * links + */ + static boolean exists(File file) { + return Files.exists(file.toPath(), LinkOption.NOFOLLOW_LINKS); + } + + /** + * Check if file is hidden (on Windows) + * + * @param file + * the file + * @return {@code true} if the given file is hidden + * @throws IOException + * if an IO error occurred + */ + static boolean isHidden(File file) throws IOException { + return Files.isHidden(toPath(file)); + } + + /** + * Set a file hidden (on Windows) + * + * @param file + * a {@link java.io.File} object. + * @param hidden + * a boolean. + * @throws java.io.IOException + * if an IO error occurred + * @since 4.1 + */ + public static void setHidden(File file, boolean hidden) throws IOException { + Files.setAttribute(toPath(file), "dos:hidden", Boolean.valueOf(hidden), //$NON-NLS-1$ + LinkOption.NOFOLLOW_LINKS); + } + + /** + * Get file length + * + * @param file + * a {@link java.io.File}. + * @return length of the given file + * @throws java.io.IOException + * if an IO error occurred + * @since 4.1 + */ + public static long getLength(File file) throws IOException { + Path nioPath = toPath(file); + if (Files.isSymbolicLink(nioPath)) + return Files.readSymbolicLink(nioPath).toString() + .getBytes(UTF_8).length; + return Files.size(nioPath); + } + + /** + * Check if file is directory + * + * @param file + * the file + * @return {@code true} if the given file is a directory, not following + * symbolic links + */ + static boolean isDirectory(File file) { + return Files.isDirectory(file.toPath(), LinkOption.NOFOLLOW_LINKS); + } + + /** + * Check if File is a file + * + * @param file + * the file + * @return {@code true} if the given file is a file, not following symbolic + * links + */ + static boolean isFile(File file) { + return Files.isRegularFile(file.toPath(), LinkOption.NOFOLLOW_LINKS); + } + + /** + * Whether the path is a directory with files in it. + * + * @param dir + * directory path + * @return {@code true} if the given directory path contains files + * @throws IOException + * on any I/O errors accessing the path + * + * @since 5.11 + */ + public static boolean hasFiles(Path dir) throws IOException { + try (Stream<Path> stream = Files.list(dir)) { + return stream.findAny().isPresent(); + } + } + + /** + * Whether the given file can be executed. + * + * @param file + * a {@link java.io.File} object. + * @return {@code true} if the given file can be executed. + * @since 4.1 + */ + public static boolean canExecute(File file) { + if (!isFile(file)) { + return false; + } + return Files.isExecutable(file.toPath()); + } + + /** + * Get basic file attributes + * + * @param fs + * a {@link org.eclipse.jgit.util.FS} object. + * @param file + * the file + * @return non null attributes object + */ + static Attributes getFileAttributesBasic(FS fs, File file) { + try { + Path nioPath = toPath(file); + BasicFileAttributes readAttributes = nioPath + .getFileSystem() + .provider() + .getFileAttributeView(nioPath, + BasicFileAttributeView.class, + LinkOption.NOFOLLOW_LINKS).readAttributes(); + Attributes attributes = new Attributes(fs, file, + true, + readAttributes.isDirectory(), + fs.supportsExecute() ? file.canExecute() : false, + readAttributes.isSymbolicLink(), + readAttributes.isRegularFile(), // + readAttributes.creationTime().toMillis(), // + readAttributes.lastModifiedTime().toInstant(), + readAttributes.isSymbolicLink() ? Constants + .encode(readSymLink(file)).length + : readAttributes.size()); + return attributes; + } catch (IOException e) { + return new Attributes(file, fs); + } + } + + /** + * Get file system attributes for the given file. + * + * @param fs + * a {@link org.eclipse.jgit.util.FS} object. + * @param file + * a {@link java.io.File}. + * @return file system attributes for the given file. + * @since 4.1 + */ + public static Attributes getFileAttributesPosix(FS fs, File file) { + try { + Path nioPath = toPath(file); + PosixFileAttributes readAttributes = nioPath + .getFileSystem() + .provider() + .getFileAttributeView(nioPath, + PosixFileAttributeView.class, + LinkOption.NOFOLLOW_LINKS).readAttributes(); + Attributes attributes = new Attributes( + fs, + file, + true, // + readAttributes.isDirectory(), // + readAttributes.permissions().contains( + PosixFilePermission.OWNER_EXECUTE), + readAttributes.isSymbolicLink(), + readAttributes.isRegularFile(), // + readAttributes.creationTime().toMillis(), // + readAttributes.lastModifiedTime().toInstant(), + readAttributes.size()); + return attributes; + } catch (IOException e) { + return new Attributes(file, fs); + } + } + + /** + * NFC normalize a file (on Mac), otherwise do nothing + * + * @param file + * a {@link java.io.File}. + * @return on Mac: NFC normalized {@link java.io.File}, otherwise the passed + * file + * @since 4.1 + */ + public static File normalize(File file) { + if (SystemReader.getInstance().isMacOS()) { + // TODO: Would it be faster to check with isNormalized first + // assuming normalized paths are much more common + String normalized = Normalizer.normalize(file.getPath(), + Normalizer.Form.NFC); + return new File(normalized); + } + return file; + } + + /** + * On Mac: get NFC normalized form of given name, otherwise the given name. + * + * @param name + * a {@link java.lang.String} object. + * @return on Mac: NFC normalized form of given name + * @since 4.1 + */ + public static String normalize(String name) { + if (SystemReader.getInstance().isMacOS()) { + if (name == null) + return null; + return Normalizer.normalize(name, Normalizer.Form.NFC); + } + return name; + } + + /** + * Best-effort variation of {@link java.io.File#getCanonicalFile()} + * returning the input file if the file cannot be canonicalized instead of + * throwing {@link java.io.IOException}. + * + * @param file + * to be canonicalized; may be {@code null} + * @return canonicalized file, or the unchanged input file if + * canonicalization failed or if {@code file == null} + * @throws java.lang.SecurityException + * if {@link java.io.File#getCanonicalFile()} throws one + * @since 4.2 + */ + public static File canonicalize(File file) { + if (file == null) { + return null; + } + try { + return file.getCanonicalFile(); + } catch (IOException e) { + return file; + } + } + + /** + * Convert a path to String, replacing separators as necessary. + * + * @param file + * a {@link java.io.File}. + * @return file's path as a String + * @since 4.10 + */ + public static String pathToString(File file) { + final String path = file.getPath(); + if (SystemReader.getInstance().isWindows()) { + return path.replace('\\', '/'); + } + return path; + } + + /** + * Touch the given file + * + * @param f + * the file to touch + * @throws IOException + * if an IO error occurred + * @since 5.1.8 + */ + public static void touch(Path f) throws IOException { + try (FileChannel fc = FileChannel.open(f, StandardOpenOption.CREATE, + StandardOpenOption.APPEND, StandardOpenOption.SYNC)) { + // touch + } + Files.setLastModifiedTime(f, FileTime.from(Instant.now())); + } + + /** + * Compute a delay in a {@code min..max} interval with random jitter. + * + * @param last + * amount of delay waited before the last attempt. This is used + * to seed the next delay interval. Should be 0 if there was no + * prior delay. + * @param min + * shortest amount of allowable delay between attempts. + * @param max + * longest amount of allowable delay between attempts. + * @return new amount of delay to wait before the next attempt. + * + * @since 5.6 + */ + public static long delay(long last, long min, long max) { + long r = Math.max(0, last * 3 - min); + if (r > 0) { + int c = (int) Math.min(r + 1, Integer.MAX_VALUE); + r = RNG.nextInt(c); + } + return Math.max(Math.min(min + r, max), min); + } } |