archive: Add tar support

Unlike ZIP files, tar files do not treat symlinks as ordinary files
with a different mode, so tar support involves a little more code than
would be ideal.

Change-Id: Ica2568f4a0e443bf4b955ef0c029bc8eec62d369

org.eclipse.jgit.pgm.test/tst/org/eclipse/jgit/pgm/ArchiveTest.java

@@ -53,11 +53,15 @@ import java.io.FileOutputStream;
 import java.io.InputStreamReader;
 import java.io.IOException;
 import java.io.OutputStream;
-
+import java.lang.Object;
 import java.lang.String;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipInputStream;
 
@@ -91,6 +95,13 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		assertArrayEquals(new String[0], listZipEntries(result));
 	}
 
+	@Test
+	public void testEmptyTar() throws Exception {
+		final byte[] result = CLIGitCommand.rawExecute( //
+				"git archive --format=tar " + emptyTree, db);
+		assertArrayEquals(new String[0], listTarEntries(result));
+	}
+
 	@Test
 	public void testArchiveWithFiles() throws Exception {
 		writeTrashFile("a", "a file with content!");
@@ -132,6 +143,32 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		assertArrayEquals(expect, actual);
 	}
 
+	@Test
+	public void testTarWithSubdir() throws Exception {
+		writeTrashFile("a", "a file with content!");
+		writeTrashFile("b.c", "before subdir in git sort order");
+		writeTrashFile("b0c", "after subdir in git sort order");
+		writeTrashFile("c", "");
+		git.add().addFilepattern("a").call();
+		git.add().addFilepattern("b.c").call();
+		git.add().addFilepattern("b0c").call();
+		git.add().addFilepattern("c").call();
+		git.commit().setMessage("populate toplevel").call();
+		writeTrashFile("b/b", "file in subdirectory");
+		writeTrashFile("b/a", "another file in subdirectory");
+		git.add().addFilepattern("b").call();
+		git.commit().setMessage("add subdir").call();
+
+		final byte[] result = CLIGitCommand.rawExecute( //
+				"git archive --format=tar master", db);
+		String[] expect = { "a", "b.c", "b0c", "b/a", "b/b", "c" };
+		String[] actual = listTarEntries(result);
+
+		Arrays.sort(expect);
+		Arrays.sort(actual);
+		assertArrayEquals(expect, actual);
+	}
+
 	@Test
 	public void testArchivePreservesMode() throws Exception {
 		writeTrashFile("plain", "a file with content");
@@ -158,6 +195,32 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		assertContainsEntryWithMode("zip-with-modes.zip", "l", "symlink");
 	}
 
+	@Test
+	public void testTarPreservesMode() throws Exception {
+		writeTrashFile("plain", "a file with content");
+		writeTrashFile("executable", "an executable file");
+		writeTrashFile("symlink", "plain");
+		git.add().addFilepattern("plain").call();
+		git.add().addFilepattern("executable").call();
+		git.add().addFilepattern("symlink").call();
+
+		DirCache cache = db.lockDirCache();
+		cache.getEntry("executable").setFileMode(FileMode.EXECUTABLE_FILE);
+		cache.getEntry("symlink").setFileMode(FileMode.SYMLINK);
+		cache.write();
+		cache.commit();
+		cache.unlock();
+
+		git.commit().setMessage("three files with different modes").call();
+
+		final byte[] archive = CLIGitCommand.rawExecute( //
+				"git archive --format=tar master", db);
+		writeRaw("with-modes.tar", archive);
+		assertTarContainsEntry("with-modes.tar", "-rw-r--r--", "plain");
+		assertTarContainsEntry("with-modes.tar", "-rwxr-xr-x", "executable");
+		assertTarContainsEntry("with-modes.tar", "l", "symlink -> plain");
+	}
+
 	@Test
 	public void testArchivePreservesContent() throws Exception {
 		final String payload = "“The quick brown fox jumps over the lazy dog!”";
@@ -171,23 +234,45 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 				zipEntryContent(result, "xyzzy"));
 	}
 
-	private void assertContainsEntryWithMode(String zipFilename, String mode, String name) //
-			throws Exception {
+	@Test
+	public void testTarPreservesContent() throws Exception {
+		final String payload = "“The quick brown fox jumps over the lazy dog!”";
+		writeTrashFile("xyzzy", payload);
+		git.add().addFilepattern("xyzzy").call();
+		git.commit().setMessage("add file with content").call();
+
+		final byte[] result = CLIGitCommand.rawExecute( //
+				"git archive --format=tar HEAD", db);
+		assertArrayEquals(new String[] { payload }, //
+				tarEntryContent(result, "xyzzy"));
+	}
+
+	private Process spawnAssumingCommandPresent(String... cmdline) {
 		final File cwd = db.getWorkTree();
-		final ProcessBuilder procBuilder = new ProcessBuilder("zipinfo", zipFilename) //
+		final ProcessBuilder procBuilder = new ProcessBuilder(cmdline) //
 				.directory(cwd) //
 				.redirectErrorStream(true);
 		Process proc = null;
 		try {
 			proc = procBuilder.start();
 		} catch (IOException e) {
-			// On machines without a "zipinfo" command, let the test pass.
+			// On machines without `cmdline[0]`, let the test pass.
 			assumeNoException(e);
 		}
 
-		proc.getOutputStream().close();
-		final BufferedReader reader = new BufferedReader( //
+		return proc;
+	}
+
+	private BufferedReader readFromProcess(Process proc) throws Exception {
+		return new BufferedReader( //
 				new InputStreamReader(proc.getInputStream(), "UTF-8"));
+	}
+
+	private void grepForEntry(String name, String mode, String... cmdline) //
+			throws Exception {
+		final Process proc = spawnAssumingCommandPresent(cmdline);
+		proc.getOutputStream().close();
+		final BufferedReader reader = readFromProcess(proc);
 		try {
 			String line;
 			while ((line = reader.readLine()) != null)
@@ -201,6 +286,16 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		}
 	}
 
+	private void assertContainsEntryWithMode(String zipFilename, String mode, String name) //
+			throws Exception {
+		grepForEntry(name, mode, "zipinfo", zipFilename);
+	}
+
+	private void assertTarContainsEntry(String tarfile, String mode, String name) //
+			throws Exception {
+		grepForEntry(name, mode, "tar", "tvf", tarfile);
+	}
+
 	private void writeRaw(String filename, byte[] data) //
 			throws IOException {
 		final File path = new File(db.getWorkTree(), filename);
@@ -224,6 +319,43 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		return l.toArray(new String[l.size()]);
 	}
 
+	private static Future<Object> writeAsync(final OutputStream stream, final byte[] data) {
+		final ExecutorService executor = Executors.newSingleThreadExecutor();
+
+		return executor.submit(new Callable<Object>() { //
+			public Object call() throws IOException {
+				try {
+					stream.write(data);
+					return null;
+				} finally {
+					stream.close();
+				}
+			}
+		});
+	}
+
+	private String[] listTarEntries(byte[] tarData) throws Exception {
+		final List<String> l = new ArrayList<String>();
+		final Process proc = spawnAssumingCommandPresent("tar", "tf", "-");
+		final BufferedReader reader = readFromProcess(proc);
+		final OutputStream out = proc.getOutputStream();
+
+		// Dump tarball to tar stdin in background
+		final Future<?> writing = writeAsync(out, tarData);
+
+		try {
+			String line;
+			while ((line = reader.readLine()) != null)
+				l.add(line);
+
+			return l.toArray(new String[l.size()]);
+		} finally {
+			writing.get();
+			reader.close();
+			proc.destroy();
+		}
+	}
+
 	private static String[] zipEntryContent(byte[] zipData, String path) //
 			throws IOException {
 		final ZipInputStream in = new ZipInputStream( //
@@ -246,4 +378,25 @@ public class ArchiveTest extends CLIRepositoryTestCase {
 		// not found
 		return null;
 	}
+
+	private String[] tarEntryContent(byte[] tarData, String path) //
+			throws Exception {
+		final List<String> l = new ArrayList<String>();
+		final Process proc = spawnAssumingCommandPresent("tar", "Oxf", "-", path);
+		final BufferedReader reader = readFromProcess(proc);
+		final OutputStream out = proc.getOutputStream();
+		final Future<?> writing = writeAsync(out, tarData);
+
+		try {
+			String line;
+			while ((line = reader.readLine()) != null)
+				l.add(line);
+
+			return l.toArray(new String[l.size()]);
+		} finally {
+			writing.get();
+			reader.close();
+			proc.destroy();
+		}
+	}
 }

org.eclipse.jgit.pgm/META-INF/MANIFEST.MF

@@ -7,6 +7,7 @@ Bundle-Vendor: %provider_name
 Bundle-Localization: plugin
 Bundle-RequiredExecutionEnvironment: J2SE-1.5
 Import-Package: org.apache.commons.compress.archivers;version="[1.3,2.0)",
+ org.apache.commons.compress.archivers.tar;version="[1.3,2.0)",
  org.apache.commons.compress.archivers.zip;version="[1.3,2.0)",
  org.eclipse.jgit.api;version="[2.2.0,2.3.0)",
  org.eclipse.jgit.api.errors;version="[2.2.0,2.3.0)",

org.eclipse.jgit.pgm/resources/org/eclipse/jgit/pgm/CLIText.properties

@@ -197,7 +197,7 @@ usage_addFileContentsToTheIndex=Add file contents to the index
 usage_alterTheDetailShown=alter the detail shown
 usage_approveDestructionOfRepository=approve destruction of repository
 usage_archive=zip up files from the named tree
-usage_archiveFormat=archive format. Currently supported formats: 'zip'
+usage_archiveFormat=archive format. Currently supported formats: 'tar', 'zip'
 usage_blameLongRevision=show long revision
 usage_blameRange=annotate only the given range
 usage_blameRawTimestamp=show raw timestamp

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Archive.java

@@ -53,6 +53,9 @@ import java.text.MessageFormat;
 
 import org.apache.commons.compress.archivers.ArchiveEntry;
 import org.apache.commons.compress.archivers.ArchiveOutputStream;
+import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
+import org.apache.commons.compress.archivers.tar.TarArchiveOutputStream;
+import org.apache.commons.compress.archivers.tar.TarConstants;
 import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
 import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
 import org.eclipse.jgit.lib.FileMode;
@@ -111,7 +114,8 @@ class Archive extends TextBuiltin {
 	}
 
 	public enum Format {
-		ZIP
+		ZIP,
+		TAR
 	};
 
 	private static interface Archiver {
@@ -149,6 +153,38 @@ class Archive extends TextBuiltin {
 				out.closeArchiveEntry();
 			}
 		});
+		fmts.put(Format.TAR, new Archiver() {
+			@Override
+			public ArchiveOutputStream createArchiveOutputStream(OutputStream s) {
+				return new TarArchiveOutputStream(s);
+			}
+
+			@Override
+			public void putEntry(String path, FileMode mode, //
+					ObjectLoader loader, ArchiveOutputStream out) //
+					throws IOException {
+				if (mode == FileMode.SYMLINK) {
+					final TarArchiveEntry entry = new TarArchiveEntry( //
+							path, TarConstants.LF_SYMLINK);
+					entry.setLinkName(new String( //
+						loader.getCachedBytes(100), "UTF-8"));
+					out.putArchiveEntry(entry);
+					out.closeArchiveEntry();
+					return;
+				}
+
+				final TarArchiveEntry entry = new TarArchiveEntry(path);
+				if (mode == FileMode.REGULAR_FILE ||
+				    mode == FileMode.EXECUTABLE_FILE)
+					entry.setMode(mode.getBits());
+				else
+					warnArchiveEntryModeIgnored(path);
+				entry.setSize(loader.getSize());
+				out.putArchiveEntry(entry);
+				loader.copyTo(out);
+				out.closeArchiveEntry();
+			}
+		});
 		formats = fmts;
 	}
 }