Merge branch 'stable-5.6' into stable-5.7

# By Matthias Sohn (3) and Han-Wen Nienhuys (1)
* stable-5.6:
  Update API problem filter
  Prepare 5.6.2-SNAPSHOT builds
  JGit v5.6.1.202002131546-r
  Simplify ReftableCompactor

Change-Id: I16ed174f9fc662934c3ebaea85a60690efbed1c6
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

6 files changed, 47 insertions, 90 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableCompactorTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableCompactorTest.java
index 874bab75ad..6fc7f25475 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableCompactorTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/reftable/ReftableCompactorTest.java
@@ -19,7 +19,9 @@ import static org.junit.Assert.assertTrue;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 
 import org.eclipse.jgit.internal.storage.io.BlockSource;
 import org.eclipse.jgit.internal.storage.reftable.ReftableWriter.Stats;
@@ -63,7 +65,9 @@ public class ReftableCompactorTest {
 		ReftableCompactor compactor;
 		try (ByteArrayOutputStream outBuf = new ByteArrayOutputStream()) {
 			compactor = new ReftableCompactor(outBuf);
-			compactor.tryAddFirst(read(inTab));
+			List<ReftableReader> readers = new ArrayList<>();
+			readers.add(read(inTab));
+			compactor.addAll(readers);
 			compactor.compact();
 			outTab = outBuf.toByteArray();
 		}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileReftableStack.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileReftableStack.java
index 4cb0bd3e80..cded6700ad 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileReftableStack.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/file/FileReftableStack.java
@@ -452,10 +452,6 @@ public class FileReftableStack implements AutoCloseable {
 		try (FileOutputStream fos = new FileOutputStream(tmpTable)) {
 			ReftableCompactor c = new ReftableCompactor(fos)
 					.setConfig(reftableConfig())
-					.setMinUpdateIndex(
-							stack.get(first).reftableReader.minUpdateIndex())
-					.setMaxUpdateIndex(
-							stack.get(last).reftableReader.maxUpdateIndex())
 					.setIncludeDeletes(first > 0);
 
 			List<ReftableReader> compactMe = new ArrayList<>();
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/MergedReftable.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/MergedReftable.java
index 63f0635f76..18c013fd8d 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/MergedReftable.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/MergedReftable.java
@@ -65,6 +65,15 @@ public class MergedReftable extends Reftable {
 				: 0;
 	}
 
+	/**
+	 * {@inheritDoc}
+	 */
+	@Override
+	public long minUpdateIndex() throws IOException {
+		return tables.length > 0 ? tables[0].minUpdateIndex()
+			: 0;
+	}
+
 	/** {@inheritDoc} */
 	@Override
 	public boolean hasObjectMap() throws IOException {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/Reftable.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/Reftable.java
index dd185f9f70..63786dc17e 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/Reftable.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/Reftable.java
@@ -65,20 +65,29 @@ public abstract class Reftable {
 		includeDeletes = deletes;
 	}
 
-
 	/**
-	 * Get the maximum update index for log entries that appear in this
+	 * Get the maximum update index for ref entries that appear in this
 	 * reftable.
 	 *
-	 * @return the maximum update index for log entries that appear in this
-	 *         reftable. This should be 1 higher than the prior reftable's
-	 *         {@code maxUpdateIndex} if this table is used in a stack.
+	 * @return the maximum update index for ref entries that appear in this
+	 *         reftable.
 	 * @throws java.io.IOException
 	 *             file cannot be read.
 	 */
 	public abstract long maxUpdateIndex() throws IOException;
 
 	/**
+	 * Get the minimum update index for ref entries that appear in this
+	 * reftable.
+	 *
+	 * @return the minimum update index for ref entries that appear in this
+	 *         reftable.
+	 * @throws java.io.IOException
+	 *             file cannot be read.
+	 */
+	public abstract long minUpdateIndex() throws IOException;
+
+	/**
 	 * Seek to the first reference, to iterate in order.
 	 *
 	 * @return cursor to iterate.
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableCompactor.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableCompactor.java
index 6bc6021783..3c4bc75792 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableCompactor.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableCompactor.java
@@ -28,22 +28,20 @@ import org.eclipse.jgit.lib.ReflogEntry;
  * to shadow any lower reftable that may have the reference present.
  * <p>
  * By default all log entries within the range defined by
- * {@link #setMinUpdateIndex(long)} and {@link #setMaxUpdateIndex(long)} are
+ * {@link #setReflogExpireMinUpdateIndex(long)} and {@link #setReflogExpireMaxUpdateIndex(long)} are
  * copied, even if no references in the output file match the log records.
  * Callers may truncate the log to a more recent time horizon with
- * {@link #setOldestReflogTimeMillis(long)}, or disable the log altogether with
+ * {@link #setReflogExpireOldestReflogTimeMillis(long)}, or disable the log altogether with
  * {@code setOldestReflogTimeMillis(Long.MAX_VALUE)}.
  */
 public class ReftableCompactor {
 	private final ReftableWriter writer;
 	private final ArrayDeque<ReftableReader> tables = new ArrayDeque<>();
 
-	private long compactBytesLimit;
-	private long bytesToCompact;
 	private boolean includeDeletes;
-	private long minUpdateIndex = -1;
-	private long maxUpdateIndex;
-	private long oldestReflogTimeMillis;
+	private long reflogExpireMinUpdateIndex = 0;
+	private long reflogExpireMaxUpdateIndex = Long.MAX_VALUE;
+	private long reflogExpireOldestReflogTimeMillis;
 	private Stats stats;
 
 	/**
@@ -70,18 +68,6 @@ public class ReftableCompactor {
 	}
 
 	/**
-	 * Set limit on number of bytes from source tables to compact.
-	 *
-	 * @param bytes
-	 *            limit on number of bytes from source tables to compact.
-	 * @return {@code this}
-	 */
-	public ReftableCompactor setCompactBytesLimit(long bytes) {
-		compactBytesLimit = bytes;
-		return this;
-	}
-
-	/**
 	 * Whether to include deletions in the output, which may be necessary for
 	 * partial compaction.
 	 *
@@ -106,8 +92,8 @@ public class ReftableCompactor {
 	 *            in a stack.
 	 * @return {@code this}
 	 */
-	public ReftableCompactor setMinUpdateIndex(long min) {
-		minUpdateIndex = min;
+	public ReftableCompactor setReflogExpireMinUpdateIndex(long min) {
+		reflogExpireMinUpdateIndex = min;
 		return this;
 	}
 
@@ -122,8 +108,8 @@ public class ReftableCompactor {
 	 *            used in a stack.
 	 * @return {@code this}
 	 */
-	public ReftableCompactor setMaxUpdateIndex(long max) {
-		maxUpdateIndex = max;
+	public ReftableCompactor setReflogExpireMaxUpdateIndex(long max) {
+		reflogExpireMaxUpdateIndex = max;
 		return this;
 	}
 
@@ -137,16 +123,13 @@ public class ReftableCompactor {
 	 *            Specified in Java standard milliseconds since the epoch.
 	 * @return {@code this}
 	 */
-	public ReftableCompactor setOldestReflogTimeMillis(long timeMillis) {
-		oldestReflogTimeMillis = timeMillis;
+	public ReftableCompactor setReflogExpireOldestReflogTimeMillis(long timeMillis) {
+		reflogExpireOldestReflogTimeMillis = timeMillis;
 		return this;
 	}
 
 	/**
 	 * Add all of the tables, in the specified order.
-	 * <p>
-	 * Unconditionally adds all tables, ignoring the
-	 * {@link #setCompactBytesLimit(long)}.
 	 *
 	 * @param readers
 	 *            tables to compact. Tables should be ordered oldest first/most
@@ -158,44 +141,7 @@ public class ReftableCompactor {
 	public void addAll(List<ReftableReader> readers) throws IOException {
 		for (ReftableReader r : readers) {
 			tables.add(r);
-			adjustUpdateIndexes(r);
-		}
-	}
-
-	/**
-	 * Try to add this reader at the bottom of the stack.
-	 * <p>
-	 * A reader may be rejected by returning {@code false} if the compactor is
-	 * already rewriting its {@link #setCompactBytesLimit(long)}. When this
-	 * happens the caller should stop trying to add tables, and execute the
-	 * compaction.
-	 *
-	 * @param reader
-	 *            the reader to insert at the bottom of the stack. Caller is
-	 *            responsible for closing the reader.
-	 * @return {@code true} if the compactor accepted this table; {@code false}
-	 *         if the compactor has reached its limit.
-	 * @throws java.io.IOException
-	 *             if size of {@code reader}, or its update indexes cannot be read.
-	 */
-	public boolean tryAddFirst(ReftableReader reader) throws IOException {
-		long sz = reader.size();
-		if (compactBytesLimit > 0 && bytesToCompact + sz > compactBytesLimit) {
-			return false;
 		}
-		bytesToCompact += sz;
-		adjustUpdateIndexes(reader);
-		tables.addFirst(reader);
-		return true;
-	}
-
-	private void adjustUpdateIndexes(ReftableReader reader) throws IOException {
-		if (minUpdateIndex == -1) {
-			minUpdateIndex = reader.minUpdateIndex();
-		} else {
-			minUpdateIndex = Math.min(minUpdateIndex, reader.minUpdateIndex());
-		}
-		maxUpdateIndex = Math.max(maxUpdateIndex, reader.maxUpdateIndex());
 	}
 
 	/**
@@ -208,8 +154,9 @@ public class ReftableCompactor {
 		MergedReftable mr = new MergedReftable(new ArrayList<>(tables));
 		mr.setIncludeDeletes(includeDeletes);
 
-		writer.setMinUpdateIndex(Math.max(minUpdateIndex, 0));
-		writer.setMaxUpdateIndex(maxUpdateIndex);
+		writer.setMaxUpdateIndex(mr.maxUpdateIndex());
+		writer.setMinUpdateIndex(mr.minUpdateIndex());
+
 		writer.begin();
 		mergeRefs(mr);
 		mergeLogs(mr);
@@ -235,16 +182,14 @@ public class ReftableCompactor {
 	}
 
 	private void mergeLogs(MergedReftable mr) throws IOException {
-		if (oldestReflogTimeMillis == Long.MAX_VALUE) {
+		if (reflogExpireOldestReflogTimeMillis == Long.MAX_VALUE) {
 			return;
 		}
 
 		try (LogCursor lc = mr.allLogs()) {
 			while (lc.next()) {
 				long updateIndex = lc.getUpdateIndex();
-				if (updateIndex < minUpdateIndex
-						|| updateIndex > maxUpdateIndex) {
-					// Cannot merge log records outside the header's range.
+				if (updateIndex > reflogExpireMaxUpdateIndex || updateIndex < reflogExpireMinUpdateIndex) {
 					continue;
 				}
 
@@ -258,7 +203,7 @@ public class ReftableCompactor {
 				}
 
 				PersonIdent who = log.getWho();
-				if (who.getWhen().getTime() >= oldestReflogTimeMillis) {
+				if (who.getWhen().getTime() >= reflogExpireOldestReflogTimeMillis) {
 					writer.writeLog(
 							refName,
 							updateIndex,
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
index c19a6d38ff..095276f57b 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/reftable/ReftableReader.java
@@ -106,15 +106,9 @@ public class ReftableReader extends Reftable implements AutoCloseable {
 	}
 
 	/**
-	 * Get the minimum update index for log entries that appear in this
-	 * reftable.
-	 *
-	 * @return the minimum update index for log entries that appear in this
-	 *         reftable. This should be 1 higher than the prior reftable's
-	 *         {@code maxUpdateIndex} if this table is used in a stack.
-	 * @throws java.io.IOException
-	 *             file cannot be read.
+	 * {@inheritDoc}
 	 */
+	@Override
 	public long minUpdateIndex() throws IOException {
 		if (blockSize == -1) {
 			readFileHeader();