Allow trailing newlines in receive-pack

C git's receive-pack.c strips trailing newlines in command lists when
present[1], although send-pack.c does not send them, at least in the
case of command lists[2]. Change JGit to match this behavior.
Add tests.

This also fixes parsing of commands in the push cert, which, unlike
commands sent in the non-push case, always have trailing newlines.

[1] 7974889a05/builtin/receive-pack.c (L1380)
where packet_read_line chomps newlines:
7974889a05/pkt-line.c (L202)

[2] 7974889a05/send-pack.c (L470)

Change-Id: I4bca6342a7482a53c9a5815a94b3c181a479d04b

org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BaseReceivePackTest.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2015, Google Inc.
+ *
+ * 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.transport;
+
+import static org.junit.Assert.assertEquals;
+
+import org.eclipse.jgit.lib.ObjectId;
+import org.junit.Test;
+
+/** Tests for base receive-pack utilities. */
+public class BaseReceivePackTest {
+	@Test
+	public void chomp() {
+		assertEquals("foo", BaseReceivePack.chomp("foo"));
+		assertEquals("foo", BaseReceivePack.chomp("foo\n"));
+		assertEquals("foo\n", BaseReceivePack.chomp("foo\n\n"));
+	}
+
+	@Test
+	public void parseCommand() {
+		String input = "0000000000000000000000000000000000000000"
+				+ " deadbeefdeadbeefdeadbeefdeadbeefdeadbeef"
+				+ " refs/heads/master";
+		ReceiveCommand cmd = BaseReceivePack.parseCommand(input);
+		assertEquals(ObjectId.zeroId(), cmd.getOldId());
+		assertEquals("deadbeefdeadbeefdeadbeefdeadbeefdeadbeef",
+				cmd.getNewId().name());
+		assertEquals("refs/heads/master", cmd.getRefName());
+	}
+}

org.eclipse.jgit/src/org/eclipse/jgit/transport/BaseReceivePack.java

@@ -1037,16 +1037,18 @@ public abstract class BaseReceivePack {
 	 */
 	protected void recvCommands() throws IOException {
 		for (;;) {
-			String line;
+			String rawLine;
 			try {
-				line = pckIn.readStringRaw();
+				rawLine = pckIn.readStringRaw();
 			} catch (EOFException eof) {
 				if (commands.isEmpty())
 					return;
 				throw eof;
 			}
-			if (line == PacketLineIn.END)
+			if (rawLine == PacketLineIn.END) {
 				break;
+			}
+			String line = chomp(rawLine);
 
 			if (line.length() >= 48 && line.startsWith("shallow ")) { //$NON-NLS-1$
 				clientShallowCommits.add(ObjectId.fromString(line.substring(8, 48)));
@@ -1066,8 +1068,11 @@ public abstract class BaseReceivePack {
 			if (line.equals("-----BEGIN PGP SIGNATURE-----\n")) //$NON-NLS-1$
 				pushCertificateParser.receiveSignature(pckIn);
 
-			if (pushCertificateParser.enabled())
-				pushCertificateParser.addCommand(line);
+			if (pushCertificateParser.enabled()) {
+				// Must use raw line with optional newline so signed payload can be
+				// reconstructed.
+				pushCertificateParser.addCommand(rawLine);
+			}
 
 			if (line.length() < 83) {
 				final String m = JGitText.get().errorInvalidProtocolWantedOldNewRef;
@@ -1075,11 +1080,8 @@ public abstract class BaseReceivePack {
 				throw new PackProtocolException(m);
 			}
 
-			final ObjectId oldId = ObjectId.fromString(line.substring(0, 40));
-			final ObjectId newId = ObjectId.fromString(line.substring(41, 81));
-			final String name = line.substring(82);
-			final ReceiveCommand cmd = new ReceiveCommand(oldId, newId, name);
-			if (name.equals(Constants.HEAD)) {
+			final ReceiveCommand cmd = parseCommand(line);
+			if (cmd.getRefName().equals(Constants.HEAD)) {
 				cmd.setResult(Result.REJECTED_CURRENT_BRANCH);
 			} else {
 				cmd.setRef(refs.get(cmd.getRefName()));
@@ -1088,6 +1090,21 @@ public abstract class BaseReceivePack {
 		}
 	}
 
+	static String chomp(String line) {
+		if (line != null && !line.isEmpty()
+				&& line.charAt(line.length() - 1) == '\n') {
+			return line.substring(0, line.length() - 1);
+		}
+		return line;
+	}
+
+	static ReceiveCommand parseCommand(String line) {
+		ObjectId oldId = ObjectId.fromString(line.substring(0, 40));
+		ObjectId newId = ObjectId.fromString(line.substring(41, 81));
+		String name = line.substring(82);
+		return new ReceiveCommand(oldId, newId, name);
+	}
+
 	/** Enable capabilities based on a previously read capabilities line. */
 	protected void enableCapabilities() {
 		sideBand = isCapabilityEnabled(CAPABILITY_SIDE_BAND_64K);