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    * and other copyright owners as documented in the project's IP log.
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  package org.eclipse.jgit.internal.storage.file;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.text.MessageFormat;
  import java.util.Arrays;
  import java.util.zip.DeflaterOutputStream;
  
  import org.eclipse.jgit.errors.CorruptObjectException;
  import org.eclipse.jgit.errors.LargeObjectException;
  import org.eclipse.jgit.internal.JGitText;
  import org.eclipse.jgit.junit.JGitTestUtil;
  import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
  import org.eclipse.jgit.junit.TestRng;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.ObjectInserter;
  import org.eclipse.jgit.lib.ObjectLoader;
  import org.eclipse.jgit.lib.ObjectStream;
  import org.eclipse.jgit.storage.file.WindowCacheConfig;
  import org.eclipse.jgit.util.FileUtils;
  import org.eclipse.jgit.util.IO;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  
  public class UnpackedObjectTest extends LocalDiskRepositoryTestCase {
  	private int streamThreshold = 16 * 1024;
  
  	private TestRng rng;
  
  	private FileRepository repo;
  
  	private WindowCursor wc;
  
  	private TestRng getRng() {
  		if (rng == null)
  			rng = new TestRng(JGitTestUtil.getName());
  		return rng;
  	}
  
  	@Override
  	@Before
  	public void setUp() throws Exception {
  		super.setUp();
 
 		WindowCacheConfig cfg = new WindowCacheConfig();
 		cfg.setStreamFileThreshold(streamThreshold);
 		cfg.install();
 
 		repo = createBareRepository();
 		wc = (WindowCursor) repo.newObjectReader();
 	}
 
 	@Override
 	@After
 	public void tearDown() throws Exception {
 		if (wc != null)
 			wc.close();
 		new WindowCacheConfig().install();
 		super.tearDown();
 	}
 
 	@Test
 	public void testStandardFormat_SmallObject() throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(300);
 		byte[] gz = compressStandardFormat(type, data);
 		ObjectId id = ObjectId.zeroId();
 
 		ObjectLoader ol = UnpackedObject.open(new ByteArrayInputStream(gz),
 				path(id), id, wc);
 		assertNotNull("created loader", ol);
 		assertEquals(type, ol.getType());
 		assertEquals(data.length, ol.getSize());
 		assertFalse("is not large", ol.isLarge());
 		assertTrue("same content", Arrays.equals(data, ol.getCachedBytes()));
 
 		try (ObjectStream in = ol.openStream()) {
 			assertNotNull("have stream", in);
 			assertEquals(type, in.getType());
 			assertEquals(data.length, in.getSize());
 			byte[] data2 = new byte[data.length];
 			IO.readFully(in, data2, 0, data.length);
 			assertTrue("same content", Arrays.equals(data2, data));
 			assertEquals("stream at EOF", -1, in.read());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_LargeObject() throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(streamThreshold + 5);
 		ObjectId id = getId(type, data);
 		write(id, compressStandardFormat(type, data));
 
 		ObjectLoader ol;
 		{
 			try (FileInputStream fs = new FileInputStream(path(id))) {
 				ol = UnpackedObject.open(fs, path(id), id, wc);
 			}
 		}
 
 		assertNotNull("created loader", ol);
 		assertEquals(type, ol.getType());
 		assertEquals(data.length, ol.getSize());
 		assertTrue("is large", ol.isLarge());
 		try {
 			ol.getCachedBytes();
 			fail("Should have thrown LargeObjectException");
 		} catch (LargeObjectException tooBig) {
 			assertEquals(MessageFormat.format(
 					JGitText.get().largeObjectException, id.name()), tooBig
 					.getMessage());
 		}
 
 		try (ObjectStream in = ol.openStream()) {
 			assertNotNull("have stream", in);
 			assertEquals(type, in.getType());
 			assertEquals(data.length, in.getSize());
 			byte[] data2 = new byte[data.length];
 			IO.readFully(in, data2, 0, data.length);
 			assertTrue("same content", Arrays.equals(data2, data));
 			assertEquals("stream at EOF", -1, in.read());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_NegativeSize() throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat("blob", "-1", data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectNegativeSize), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_InvalidType() throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat("not.a.type", "1", data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectInvalidType), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_NoHeader() throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = {};
 
 		try {
 			byte[] gz = compressStandardFormat("", "", data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectNoHeader), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_GarbageAfterSize() throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat("blob", "1foo", data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectGarbageAfterSize),
 					coe.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_SmallObject_CorruptZLibStream()
 			throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat(Constants.OBJ_BLOB, data);
 			for (int i = 5; i < gz.length; i++)
 				gz[i] = 0;
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_SmallObject_TruncatedZLibStream()
 			throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat(Constants.OBJ_BLOB, data);
 			byte[] tr = new byte[gz.length - 1];
 			System.arraycopy(gz, 0, tr, 0, tr.length);
 			UnpackedObject.open(new ByteArrayInputStream(tr), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_SmallObject_TrailingGarbage()
 			throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressStandardFormat(Constants.OBJ_BLOB, data);
 			byte[] tr = new byte[gz.length + 1];
 			System.arraycopy(gz, 0, tr, 0, gz.length);
 			UnpackedObject.open(new ByteArrayInputStream(tr), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_LargeObject_CorruptZLibStream()
 			throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(streamThreshold + 5);
 		ObjectId id = getId(type, data);
 		byte[] gz = compressStandardFormat(type, data);
 		gz[gz.length - 1] = 0;
 		gz[gz.length - 2] = 0;
 
 		write(id, gz);
 
 		ObjectLoader ol;
 		try (FileInputStream fs = new FileInputStream(path(id))) {
 			ol = UnpackedObject.open(fs, path(id), id, wc);
 		}
 
 		byte[] tmp = new byte[data.length];
 		try (InputStream in = ol.openStream()) {
 			IO.readFully(in, tmp, 0, tmp.length);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_LargeObject_TruncatedZLibStream()
 			throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(streamThreshold + 5);
 		ObjectId id = getId(type, data);
 		byte[] gz = compressStandardFormat(type, data);
 		byte[] tr = new byte[gz.length - 1];
 		System.arraycopy(gz, 0, tr, 0, tr.length);
 
 		write(id, tr);
 
 		ObjectLoader ol;
 		try (FileInputStream fs = new FileInputStream(path(id))) {
 			ol = UnpackedObject.open(fs, path(id), id, wc);
 		}
 
 		byte[] tmp = new byte[data.length];
 		@SuppressWarnings("resource") // We are testing that the close() method throws
 		InputStream in = ol.openStream();
 		IO.readFully(in, tmp, 0, tmp.length);
 		try {
 			in.close();
 			fail("close did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testStandardFormat_LargeObject_TrailingGarbage()
 			throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(streamThreshold + 5);
 		ObjectId id = getId(type, data);
 		byte[] gz = compressStandardFormat(type, data);
 		byte[] tr = new byte[gz.length + 1];
 		System.arraycopy(gz, 0, tr, 0, gz.length);
 
 		write(id, tr);
 
 		ObjectLoader ol;
 		try (FileInputStream fs = new FileInputStream(path(id))) {
 			ol = UnpackedObject.open(fs, path(id), id, wc);
 		}
 
 		byte[] tmp = new byte[data.length];
 		@SuppressWarnings("resource") // We are testing that the close() method throws
 		InputStream in = ol.openStream();
 		IO.readFully(in, tmp, 0, tmp.length);
 		try {
 			in.close();
 			fail("close did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectBadStream), coe
 					.getMessage());
 		}
 	}
 
 	@Test
 	public void testPackFormat_SmallObject() throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(300);
 		byte[] gz = compressPackFormat(type, data);
 		ObjectId id = ObjectId.zeroId();
 
 		ObjectLoader ol = UnpackedObject.open(new ByteArrayInputStream(gz),
 				path(id), id, wc);
 		assertNotNull("created loader", ol);
 		assertEquals(type, ol.getType());
 		assertEquals(data.length, ol.getSize());
 		assertFalse("is not large", ol.isLarge());
 		assertTrue("same content", Arrays.equals(data, ol.getCachedBytes()));
 
 		try (ObjectStream in = ol.openStream()) {
 			assertNotNull("have stream", in);
 			assertEquals(type, in.getType());
 			assertEquals(data.length, in.getSize());
 			byte[] data2 = new byte[data.length];
 			IO.readFully(in, data2, 0, data.length);
 			assertTrue("same content",
 					Arrays.equals(data, ol.getCachedBytes()));
 		}
 	}
 
 	@Test
 	public void testPackFormat_LargeObject() throws Exception {
 		final int type = Constants.OBJ_BLOB;
 		byte[] data = getRng().nextBytes(streamThreshold + 5);
 		ObjectId id = getId(type, data);
 		write(id, compressPackFormat(type, data));
 
 		ObjectLoader ol;
 		try (FileInputStream fs = new FileInputStream(path(id))) {
 			ol = UnpackedObject.open(fs, path(id), id, wc);
 		}
 
 		assertNotNull("created loader", ol);
 		assertEquals(type, ol.getType());
 		assertEquals(data.length, ol.getSize());
 		assertTrue("is large", ol.isLarge());
 		try {
 			ol.getCachedBytes();
 			fail("Should have thrown LargeObjectException");
 		} catch (LargeObjectException tooBig) {
 			assertEquals(MessageFormat.format(
 					JGitText.get().largeObjectException, id.name()), tooBig
 					.getMessage());
 		}
 
 		try (ObjectStream in = ol.openStream()) {
 			assertNotNull("have stream", in);
 			assertEquals(type, in.getType());
 			assertEquals(data.length, in.getSize());
 			byte[] data2 = new byte[data.length];
 			IO.readFully(in, data2, 0, data.length);
 			assertTrue("same content", Arrays.equals(data2, data));
 			assertEquals("stream at EOF", -1, in.read());
 		}
 	}
 
 	@Test
 	public void testPackFormat_DeltaNotAllowed() throws Exception {
 		ObjectId id = ObjectId.zeroId();
 		byte[] data = getRng().nextBytes(300);
 
 		try {
 			byte[] gz = compressPackFormat(Constants.OBJ_OFS_DELTA, data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectInvalidType), coe
 					.getMessage());
 		}
 
 		try {
 			byte[] gz = compressPackFormat(Constants.OBJ_REF_DELTA, data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectInvalidType), coe
 					.getMessage());
 		}
 
 		try {
 			byte[] gz = compressPackFormat(Constants.OBJ_TYPE_5, data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectInvalidType), coe
 					.getMessage());
 		}
 
 		try {
 			byte[] gz = compressPackFormat(Constants.OBJ_EXT, data);
 			UnpackedObject.open(new ByteArrayInputStream(gz), path(id), id, wc);
 			fail("Did not throw CorruptObjectException");
 		} catch (CorruptObjectException coe) {
 			assertEquals(MessageFormat.format(JGitText.get().objectIsCorrupt,
 					id.name(), JGitText.get().corruptObjectInvalidType), coe
 					.getMessage());
 		}
 	}
 
 	private static byte[] compressStandardFormat(int type, byte[] data)
 			throws IOException {
 		String typeString = Constants.typeString(type);
 		String length = String.valueOf(data.length);
 		return compressStandardFormat(typeString, length, data);
 	}
 
 	private static byte[] compressStandardFormat(String type, String length,
 			byte[] data) throws IOException {
 		ByteArrayOutputStream out = new ByteArrayOutputStream();
 		DeflaterOutputStream d = new DeflaterOutputStream(out);
 		d.write(Constants.encodeASCII(type));
 		d.write(' ');
 		d.write(Constants.encodeASCII(length));
 		d.write(0);
 		d.write(data);
 		d.finish();
 		return out.toByteArray();
 	}
 
 	private static byte[] compressPackFormat(int type, byte[] data)
 			throws IOException {
 		byte[] hdr = new byte[64];
 		int rawLength = data.length;
 		int nextLength = rawLength >>> 4;
 		hdr[0] = (byte) ((nextLength > 0 ? 0x80 : 0x00) | (type << 4) | (rawLength & 0x0F));
 		rawLength = nextLength;
 		int n = 1;
 		while (rawLength > 0) {
 			nextLength >>>= 7;
 			hdr[n++] = (byte) ((nextLength > 0 ? 0x80 : 0x00) | (rawLength & 0x7F));
 			rawLength = nextLength;
 		}
 
 		final ByteArrayOutputStream out = new ByteArrayOutputStream();
 		out.write(hdr, 0, n);
 
 		DeflaterOutputStream d = new DeflaterOutputStream(out);
 		d.write(data);
 		d.finish();
 		return out.toByteArray();
 	}
 
 	private File path(ObjectId id) {
 		return repo.getObjectDatabase().fileFor(id);
 	}
 
 	private void write(ObjectId id, byte[] data) throws IOException {
 		File path = path(id);
 		FileUtils.mkdirs(path.getParentFile());
 		try (FileOutputStream out = new FileOutputStream(path)) {
 			out.write(data);
 		}
 	}
 
 	private ObjectId getId(int type, byte[] data) {
 		try (ObjectInserter.Formatter formatter = new ObjectInserter.Formatter()) {
 			return formatter.idFor(type, data);
 		}
 	}
 }