diff options
5 files changed, 107 insertions, 9 deletions
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java index 902416bdff..07b1bc789d 100644 --- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java +++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java @@ -42,6 +42,7 @@ */ package org.eclipse.jgit.internal.storage.file; +import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertFalse; import static org.junit.Assert.assertTrue; @@ -99,6 +100,27 @@ public class FileSnapshotTest { } /** + * Check that file is modified by looking at its size. + * + * @throws Exception + */ + @Test + public void tesIsModifiedBySameLastModifiedAndDifferentSize() throws Exception { + File f1 = createFile("foo", "lorem".getBytes()); + File f2 = createFile("bar", "lorem ipsum".getBytes()); + + f1.setLastModified(f2.lastModified()); // Make sure f1 and f2 have the same lastModified + FileSnapshot save = FileSnapshot.save(f1); + + // Make sure that the modified and read timestamps are far enough, so that + // check is done by size + Thread.sleep(3000L); + + assertEquals(save.lastModified(), f2.lastModified()); + assertTrue(save.isModified(f2)); + } + + /** * Create a file, wait long enough and verify that it has not been modified. * 3.5 seconds mean any difference between file system timestamp and system * clock should be significant. @@ -152,10 +174,22 @@ public class FileSnapshotTest { return f; } + private File createFile(String string, byte[] content) throws IOException { + File f = createFile(string); + append(f, content); + return f; + } + private static void append(File f, byte b) throws IOException { + append(f, new byte[] { b }); + } + + private static void append(File f, byte[] content) throws IOException { FileOutputStream os = new FileOutputStream(f, true); try { - os.write(b); + for (byte b : content) { + os.write(b); + } } finally { os.close(); } diff --git a/org.eclipse.jgit/.settings/.api_filters b/org.eclipse.jgit/.settings/.api_filters index d259fc85f0..fe83211ebc 100644 --- a/org.eclipse.jgit/.settings/.api_filters +++ b/org.eclipse.jgit/.settings/.api_filters @@ -22,4 +22,12 @@ </message_arguments> </filter> </resource> + <resource path="src/org/eclipse/jgit/util/FS.java" type="org.eclipse.jgit.util.FS"> + <filter id="1142947843"> + <message_arguments> + <message_argument value="4.5.6"/> + <message_argument value="fileAttributes(File)"/> + </message_arguments> + </filter> + </resource> </component> diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java index 8926d79306..fbd1dbf696 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileSnapshot.java @@ -45,6 +45,7 @@ package org.eclipse.jgit.internal.storage.file; import java.io.File; import java.io.IOException; +import java.nio.file.attribute.BasicFileAttributes; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; @@ -70,13 +71,20 @@ import org.eclipse.jgit.util.FS; */ public class FileSnapshot { /** + * An unknown file size. + * + * This value is used when a comparison needs to happen purely on the lastUpdate. + */ + public static final long UNKNOWN_SIZE = -1; + + /** * A FileSnapshot that is considered to always be modified. * <p> * This instance is useful for application code that wants to lazily read a * file, but only after {@link #isModified(File)} gets invoked. The returned * snapshot contains only invalid status information. */ - public static final FileSnapshot DIRTY = new FileSnapshot(-1, -1); + public static final FileSnapshot DIRTY = new FileSnapshot(-1, -1, UNKNOWN_SIZE); /** * A FileSnapshot that is clean if the file does not exist. @@ -85,7 +93,7 @@ public class FileSnapshot { * file to be clean. {@link #isModified(File)} will return false if the file * path does not exist. */ - public static final FileSnapshot MISSING_FILE = new FileSnapshot(0, 0) { + public static final FileSnapshot MISSING_FILE = new FileSnapshot(0, 0, 0) { @Override public boolean isModified(File path) { return FS.DETECTED.exists(path); @@ -105,12 +113,16 @@ public class FileSnapshot { public static FileSnapshot save(File path) { long read = System.currentTimeMillis(); long modified; + long size; try { - modified = FS.DETECTED.lastModified(path); + BasicFileAttributes fileAttributes = FS.DETECTED.fileAttributes(path); + modified = fileAttributes.lastModifiedTime().toMillis(); + size = fileAttributes.size(); } catch (IOException e) { modified = path.lastModified(); + size = path.length(); } - return new FileSnapshot(read, modified); + return new FileSnapshot(read, modified, size); } /** @@ -126,7 +138,7 @@ public class FileSnapshot { */ public static FileSnapshot save(long modified) { final long read = System.currentTimeMillis(); - return new FileSnapshot(read, modified); + return new FileSnapshot(read, modified, -1); } /** Last observed modification time of the path. */ @@ -138,10 +150,16 @@ public class FileSnapshot { /** True once {@link #lastRead} is far later than {@link #lastModified}. */ private boolean cannotBeRacilyClean; - private FileSnapshot(long read, long modified) { + /** Underlying file-system size in bytes. + * + * When set to {@link #UNKNOWN_SIZE} the size is not considered for modification checks. */ + private final long size; + + private FileSnapshot(long read, long modified, long size) { this.lastRead = read; this.lastModified = modified; this.cannotBeRacilyClean = notRacyClean(read); + this.size = size; } /** @@ -152,6 +170,13 @@ public class FileSnapshot { } /** + * @return file size in bytes of last snapshot update + */ + public long size() { + return size; + } + + /** * Check if the path may have been modified since the snapshot was saved. * * @param path @@ -160,12 +185,16 @@ public class FileSnapshot { */ public boolean isModified(File path) { long currLastModified; + long currSize; try { - currLastModified = FS.DETECTED.lastModified(path); + BasicFileAttributes fileAttributes = FS.DETECTED.fileAttributes(path); + currLastModified = fileAttributes.lastModifiedTime().toMillis(); + currSize = fileAttributes.size(); } catch (IOException e) { currLastModified = path.lastModified(); + currSize = path.length(); } - return isModified(currLastModified); + return (currSize != UNKNOWN_SIZE && currSize != size) || isModified(currLastModified); } /** diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java index e1fd1cb889..530b1d4bc2 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FS.java @@ -52,6 +52,7 @@ import java.io.InputStreamReader; import java.io.OutputStream; import java.io.PrintStream; import java.nio.charset.Charset; +import java.nio.file.attribute.BasicFileAttributes; import java.security.AccessController; import java.security.PrivilegedAction; import java.text.MessageFormat; @@ -418,6 +419,19 @@ public abstract class FS { public abstract boolean retryFailedLockFileCommit(); /** + * Return all the attributes of a file, without following symbolic links. + * + * @param file + * @return {@link BasicFileAttributes} of the file + * @throws IOException in case of any I/O errors accessing the file + * + * @since 4.5.6 + */ + public BasicFileAttributes fileAttributes(File file) throws IOException { + return FileUtils.fileAttributes(file); + } + + /** * Determine the user's home directory (location where preferences are). * * @return the user's home directory; null if the user does not have one. 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 aa101f73f9..88b1f9ea01 100644 --- a/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java +++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java @@ -565,6 +565,19 @@ public class FileUtils { } /** + * Return all the attributes of a file, without following symbolic links. + * + * @param 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); + } + + /** * @param file * @param time * @throws IOException |