Move ArchiveCommand into standard porcelain API

Allow use of ArchiveCommand without depending on the jgit command-line
tools.

To avoid complicating the process of installing and upgrading JGit,
this does not add a dependency by the org.eclipse.jgit bundle on
commons-compress.  Instead, the caller is responsible for registering
any formats they want to use by calling ArchiveCommand.registerFormat.

This patch puts functionality that requires an archiver into a
separate org.eclipse.jgit.archive bundle for people who want it.  One
can use it by calling ArchiveCommand.registerFormat directly to
register its formats or by relying on OSGi class loading to load
org.eclipse.jgit.archive.FormatActivator, which takes care of
registration automatically.

Once the appropriate formats are registered, you can make a tar or zip
from a git tree object as follows:

	ArchiveCommand cmd = git.archive();
	try {
		cmd.setTree(tree).setFormat(fmt).setOutputStream(out).call();
	} finally {
		cmd.release();
	}

Change-Id: I418e7e7d76422dc6f010d0b3b624d7bec3b20c6e

3 files changed, 225 insertions, 0 deletions

diff --git a/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/FormatActivator.java b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/FormatActivator.java
new file mode 100644
index 0000000000..8c0a581530
--- /dev/null
+++ b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/FormatActivator.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2013 Google Inc.
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.eclipse.jgit.archive;
+
+import org.eclipse.jgit.api.ArchiveCommand;
+import org.osgi.framework.BundleActivator;
+import org.osgi.framework.BundleContext;
+
+public class FormatActivator implements BundleActivator {
+	public void start(BundleContext context) throws Exception {
+		ArchiveCommand.registerFormat("tar", new TarFormat());
+		ArchiveCommand.registerFormat("zip", new ZipFormat());
+	}
+
+	public void stop(BundleContext context) throws Exception {
+		ArchiveCommand.unregisterFormat("zip");
+		ArchiveCommand.unregisterFormat("tar");
+	}
+}
diff --git a/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/TarFormat.java b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/TarFormat.java
new file mode 100644
index 0000000000..2e5683c2b5
--- /dev/null
+++ b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/TarFormat.java
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2012 Google Inc.
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.eclipse.jgit.archive;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+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.eclipse.jgit.api.ArchiveCommand;
+import org.eclipse.jgit.lib.FileMode;
+import org.eclipse.jgit.lib.ObjectLoader;
+
+public class TarFormat implements ArchiveCommand.Format<ArchiveOutputStream> {
+	public ArchiveOutputStream createArchiveOutputStream(OutputStream s) {
+		return new TarArchiveOutputStream(s);
+	}
+
+	public void putEntry(ArchiveOutputStream out,
+			String path, FileMode mode, ObjectLoader loader)
+			throws IOException {
+		if (mode == FileMode.SYMLINK) {
+			final TarArchiveEntry entry = new TarArchiveEntry(
+					path, TarConstants.LF_SYMLINK);
+			entry.setLinkName(new String(
+					loader.getCachedBytes(100), "UTF-8")); //$NON-NLS-1$
+			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 {
+			// TODO(jrn): Let the caller know the tree contained
+			// an entry with unsupported mode (e.g., a submodule).
+		}
+		entry.setSize(loader.getSize());
+		out.putArchiveEntry(entry);
+		loader.copyTo(out);
+		out.closeArchiveEntry();
+	}
+}
diff --git a/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/ZipFormat.java b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/ZipFormat.java
new file mode 100644
index 0000000000..19328775a4
--- /dev/null
+++ b/org.eclipse.jgit.archive/src/org/eclipse/jgit/archive/ZipFormat.java
@@ -0,0 +1,79 @@
+/*
+ * Copyright (C) 2012 Google Inc.
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.eclipse.jgit.archive;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+import org.apache.commons.compress.archivers.ArchiveOutputStream;
+import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
+import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream;
+import org.eclipse.jgit.api.ArchiveCommand;
+import org.eclipse.jgit.lib.FileMode;
+import org.eclipse.jgit.lib.ObjectLoader;
+
+public class ZipFormat implements ArchiveCommand.Format<ArchiveOutputStream> {
+	public ArchiveOutputStream createArchiveOutputStream(OutputStream s) {
+		return new ZipArchiveOutputStream(s);
+	}
+
+	public void putEntry(ArchiveOutputStream out,
+			String path, FileMode mode, ObjectLoader loader)
+			throws IOException {
+		final ZipArchiveEntry entry = new ZipArchiveEntry(path);
+
+		if (mode == FileMode.REGULAR_FILE) {
+			// ok
+		} else if (mode == FileMode.EXECUTABLE_FILE
+				|| mode == FileMode.SYMLINK) {
+			entry.setUnixMode(mode.getBits());
+		} else {
+			// TODO(jrn): Let the caller know the tree contained
+			// an entry with unsupported mode (e.g., a submodule).
+		}
+		entry.setSize(loader.getSize());
+		out.putArchiveEntry(entry);
+		loader.copyTo(out);
+		out.closeArchiveEntry();
+	}
+}