| /* |
| * Copyright (C) 2008-2010, Google Inc. |
| * Copyright (C) 2008-2009, Robin Rosenberg <robin.rosenberg@dewire.com> |
| * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> and others |
| * |
| * 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.transport; |
| |
| import static java.nio.charset.StandardCharsets.UTF_8; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| import org.eclipse.jgit.lib.Constants; |
| import org.eclipse.jgit.util.RawParseUtils; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Write Git style pkt-line formatting to an output stream. |
| * <p> |
| * This class is not thread safe and may issue multiple writes to the underlying |
| * stream for each method call made. |
| * <p> |
| * This class performs no buffering on its own. This makes it suitable to |
| * interleave writes performed by this class with writes performed directly |
| * against the underlying OutputStream. |
| */ |
| public class PacketLineOut { |
| private static final Logger log = LoggerFactory.getLogger(PacketLineOut.class); |
| |
| private final OutputStream out; |
| |
| private final byte[] lenbuffer; |
| |
| private boolean flushOnEnd; |
| |
| private boolean usingSideband; |
| |
| /** |
| * Create a new packet line writer. |
| * |
| * @param outputStream |
| * stream. |
| */ |
| public PacketLineOut(OutputStream outputStream) { |
| out = outputStream; |
| lenbuffer = new byte[5]; |
| flushOnEnd = true; |
| } |
| |
| /** |
| * Set the flush behavior during {@link #end()}. |
| * |
| * @param flushOnEnd |
| * if true, a flush-pkt written during {@link #end()} also |
| * flushes the underlying stream. |
| */ |
| public void setFlushOnEnd(boolean flushOnEnd) { |
| this.flushOnEnd = flushOnEnd; |
| } |
| |
| /** |
| * @return whether to add a sideband designator to each non-flush and |
| * non-delim packet |
| * @see #setUsingSideband |
| * @since 5.5 |
| */ |
| public boolean isUsingSideband() { |
| return usingSideband; |
| } |
| |
| /** |
| * @param value If true, when writing packet lines, add, as the first |
| * byte, a sideband designator to each non-flush and non-delim |
| * packet. See pack-protocol.txt and protocol-v2.txt from the Git |
| * project for more information, specifically the "side-band" and |
| * "sideband-all" sections. |
| * @since 5.5 |
| */ |
| public void setUsingSideband(boolean value) { |
| this.usingSideband = value; |
| } |
| |
| /** |
| * Write a UTF-8 encoded string as a single length-delimited packet. |
| * |
| * @param s |
| * string to write. |
| * @throws java.io.IOException |
| * the packet could not be written, the stream is corrupted as |
| * the packet may have been only partially written. |
| */ |
| public void writeString(String s) throws IOException { |
| writePacket(Constants.encode(s)); |
| } |
| |
| /** |
| * Write a binary packet to the stream. |
| * |
| * @param packet |
| * the packet to write; the length of the packet is equal to the |
| * size of the byte array. |
| * @throws java.io.IOException |
| * the packet could not be written, the stream is corrupted as |
| * the packet may have been only partially written. |
| */ |
| public void writePacket(byte[] packet) throws IOException { |
| writePacket(packet, 0, packet.length); |
| } |
| |
| /** |
| * Write a binary packet to the stream. |
| * |
| * @param buf |
| * the packet to write |
| * @param pos |
| * first index within {@code buf}. |
| * @param len |
| * number of bytes to write. |
| * @throws java.io.IOException |
| * the packet could not be written, the stream is corrupted as |
| * the packet may have been only partially written. |
| * @since 4.5 |
| */ |
| public void writePacket(byte[] buf, int pos, int len) throws IOException { |
| if (usingSideband) { |
| formatLength(len + 5); |
| out.write(lenbuffer, 0, 4); |
| out.write(1); |
| } else { |
| formatLength(len + 4); |
| out.write(lenbuffer, 0, 4); |
| } |
| out.write(buf, pos, len); |
| if (log.isDebugEnabled()) { |
| String s = RawParseUtils.decode(UTF_8, buf, pos, len); |
| log.debug("git> " + s); //$NON-NLS-1$ |
| } |
| } |
| |
| /** |
| * Write a packet delim marker (0001). |
| * |
| * @throws java.io.IOException |
| * the marker could not be written, the stream is corrupted |
| * as the marker may have been only partially written. |
| * @since 5.0 |
| */ |
| public void writeDelim() throws IOException { |
| formatLength(1); |
| out.write(lenbuffer, 0, 4); |
| log.debug("git> 0001"); //$NON-NLS-1$ |
| } |
| |
| /** |
| * Write a packet end marker, sometimes referred to as a flush command. |
| * <p> |
| * Technically this is a magical packet type which can be detected |
| * separately from an empty string or an empty packet. |
| * <p> |
| * Implicitly performs a flush on the underlying OutputStream to ensure the |
| * peer will receive all data written thus far. |
| * |
| * @throws java.io.IOException |
| * the end marker could not be written, the stream is corrupted |
| * as the end marker may have been only partially written. |
| */ |
| public void end() throws IOException { |
| formatLength(0); |
| out.write(lenbuffer, 0, 4); |
| log.debug("git> 0000"); //$NON-NLS-1$ |
| if (flushOnEnd) |
| flush(); |
| } |
| |
| /** |
| * Flush the underlying OutputStream. |
| * <p> |
| * Performs a flush on the underlying OutputStream to ensure the peer will |
| * receive all data written thus far. |
| * |
| * @throws java.io.IOException |
| * the underlying stream failed to flush. |
| */ |
| public void flush() throws IOException { |
| out.flush(); |
| } |
| |
| private static final byte[] hexchar = { '0', '1', '2', '3', '4', '5', '6', |
| '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' }; |
| |
| private void formatLength(int w) { |
| formatLength(lenbuffer, w); |
| } |
| |
| static void formatLength(byte[] lenbuffer, int w) { |
| int o = 3; |
| while (o >= 0 && w != 0) { |
| lenbuffer[o--] = hexchar[w & 0xf]; |
| w >>>= 4; |
| } |
| while (o >= 0) |
| lenbuffer[o--] = '0'; |
| } |
| } |