1 files changed, 107 insertions, 0 deletions
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/MultiPackIndex.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/MultiPackIndex.java
new file mode 100644
index 0000000000..1844223cc9
--- /dev/null
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/MultiPackIndex.java
@@ -0,0 +1,107 @@
+/*
+ * Copyright (C) 2025, Google LLC.
+ *
+ * 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.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+package org.eclipse.jgit.pgm;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.eclipse.jgit.internal.storage.file.ObjectDirectory;
+import org.eclipse.jgit.internal.storage.file.Pack;
+import org.eclipse.jgit.internal.storage.file.PackFile;
+import org.eclipse.jgit.internal.storage.file.PackIndex;
+import org.eclipse.jgit.internal.storage.midx.MultiPackIndexPrettyPrinter;
+import org.eclipse.jgit.internal.storage.midx.MultiPackIndexWriter;
+import org.eclipse.jgit.internal.storage.pack.PackExt;
+import org.eclipse.jgit.lib.NullProgressMonitor;
+import org.kohsuke.args4j.Argument;
+import org.kohsuke.args4j.Option;
+
+@Command(common = true, usage = "usage_MultiPackIndex")
+@SuppressWarnings("nls")
+class MultiPackIndex extends TextBuiltin {
+	@Argument(index = 0, required = true, usage = "write, print")
+	private String command;
+
+	@Option(name = "--midx")
+	private String midxPath;
+
+	/** {@inheritDoc} */
+	@Override
+	protected void run() throws IOException {
+		switch (command) {
+		case "print":
+			printMultiPackIndex();
+			break;
+		case "write":
+			writeMultiPackIndex();
+			break;
+		default:
+			outw.println("Unknown command " + command);
+		}
+	}
+
+	private void printMultiPackIndex() {
+		if (midxPath == null || midxPath.isEmpty()) {
+			throw die("'print' requires the path of a multipack "
+					+ "index file with --midx option.");
+		}
+
+		try (FileInputStream is = new FileInputStream(midxPath)) {
+			PrintWriter pw = new PrintWriter(outw, true);
+			MultiPackIndexPrettyPrinter.prettyPrint(is.readAllBytes(), pw);
+		} catch (FileNotFoundException e) {
+			throw die(true, e);
+		} catch (IOException e) {
+			throw die(true, e);
+		}
+	}
+
+	private void writeMultiPackIndex() throws IOException {
+		if (!(db.getObjectDatabase() instanceof ObjectDirectory)) {
+			throw die("This repository object db doesn't have packs");
+		}
+
+		File midx;
+		if (midxPath == null || midxPath.isEmpty()) {
+			midx = new File(((ObjectDirectory) db.getObjectDatabase())
+					.getPackDirectory(), "multi-pack-index");
+		} else {
+			midx = new File(midxPath);
+		}
+
+		errw.println("Writing " + midx.getAbsolutePath());
+
+		ObjectDirectory odb = (ObjectDirectory) db.getObjectDatabase();
+
+		Map<String, PackIndex> indexes = new HashMap<>();
+		for (Pack pack : odb.getPacks()) {
+			PackFile packFile = pack.getPackFile().create(PackExt.INDEX);
+			try {
+				indexes.put(packFile.getName(), pack.getIndex());
+			} catch (IOException e) {
+				throw die("Cannot open index in pack", e);
+			}
+		}
+
+		MultiPackIndexWriter writer = new MultiPackIndexWriter();
+		try (FileOutputStream out = new FileOutputStream(midxPath)) {
+			writer.write(NullProgressMonitor.INSTANCE, out, indexes);
+		} catch (IOException e) {
+			throw die("Cannot write midx " + midxPath, e);
+		}
+	}
+}