tikhomirov@530: /*
tikhomirov@530:  * Copyright (c) 2013 TMate Software Ltd
tikhomirov@530:  *  
tikhomirov@530:  * This program is free software; you can redistribute it and/or modify
tikhomirov@530:  * it under the terms of the GNU General Public License as published by
tikhomirov@530:  * the Free Software Foundation; version 2 of the License.
tikhomirov@530:  *
tikhomirov@530:  * This program is distributed in the hope that it will be useful,
tikhomirov@530:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@530:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@530:  * GNU General Public License for more details.
tikhomirov@530:  *
tikhomirov@530:  * For information on how to redistribute this software under
tikhomirov@530:  * the terms of a license other than GNU General Public License
tikhomirov@530:  * contact TMate Software at support@hg4j.com
tikhomirov@530:  */
tikhomirov@530: package org.tmatesoft.hg.internal;
tikhomirov@530: 
tikhomirov@530: import static org.tmatesoft.hg.internal.Internals.REVLOGV1_RECORD_SIZE;
tikhomirov@534: import static org.tmatesoft.hg.repo.HgRepository.NO_REVISION;
tikhomirov@530: 
tikhomirov@530: import java.io.IOException;
tikhomirov@530: import java.nio.ByteBuffer;
tikhomirov@530: 
tikhomirov@530: import org.tmatesoft.hg.core.Nodeid;
tikhomirov@534: import org.tmatesoft.hg.core.SessionContext;
tikhomirov@534: import org.tmatesoft.hg.repo.HgInvalidControlFileException;
tikhomirov@534: import org.tmatesoft.hg.repo.HgInvalidStateException;
tikhomirov@530: 
tikhomirov@530: /**
tikhomirov@530:  * 
tikhomirov@534:  * TODO separate operation to check if index is too big and split into index+data
tikhomirov@532:  * 
tikhomirov@530:  * @author Artem Tikhomirov
tikhomirov@530:  * @author TMate Software Ltd.
tikhomirov@530:  */
tikhomirov@530: public class RevlogStreamWriter {
tikhomirov@530: 
tikhomirov@530: 	
tikhomirov@534: 	/*XXX public because HgCloneCommand uses it*/
tikhomirov@534: 	public static class HeaderWriter implements DataSerializer.DataSource {
tikhomirov@530: 		private final ByteBuffer header;
tikhomirov@530: 		private final boolean isInline;
tikhomirov@530: 		private long offset;
tikhomirov@530: 		private int length, compressedLength;
tikhomirov@530: 		private int baseRev, linkRev, p1, p2;
tikhomirov@534: 		private byte[] nodeid;
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter(boolean inline) {
tikhomirov@530: 			isInline = inline;
tikhomirov@530: 			header = ByteBuffer.allocate(REVLOGV1_RECORD_SIZE);
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter offset(long offset) {
tikhomirov@530: 			this.offset = offset;
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@532: 		public int baseRevision() {
tikhomirov@532: 			return baseRev;
tikhomirov@532: 		}
tikhomirov@532: 		
tikhomirov@530: 		public HeaderWriter baseRevision(int baseRevision) {
tikhomirov@530: 			this.baseRev = baseRevision;
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter length(int len, int compressedLen) {
tikhomirov@530: 			this.length = len;
tikhomirov@530: 			this.compressedLength = compressedLen;
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter parents(int parent1, int parent2) {
tikhomirov@530: 			p1 = parent1;
tikhomirov@530: 			p2 = parent2;
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter linkRevision(int linkRevision) {
tikhomirov@534: 			linkRev = linkRevision;
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@530: 		
tikhomirov@530: 		public HeaderWriter nodeid(Nodeid n) {
tikhomirov@534: 			nodeid = n.toByteArray();
tikhomirov@530: 			return this;
tikhomirov@530: 		}
tikhomirov@534: 		
tikhomirov@534: 		public HeaderWriter nodeid(byte[] nodeidBytes) {
tikhomirov@534: 			nodeid = nodeidBytes;
tikhomirov@534: 			return this;
tikhomirov@534: 		}
tikhomirov@534: 		
tikhomirov@534: 		public void serialize(DataSerializer out) throws IOException {
tikhomirov@530: 			header.clear();
tikhomirov@530: 			if (offset == 0) {
tikhomirov@530: 				int version = 1 /* RevlogNG */;
tikhomirov@530: 				if (isInline) {
tikhomirov@530: 					final int INLINEDATA = 1 << 16; // FIXME extract constant
tikhomirov@530: 					version |= INLINEDATA;
tikhomirov@530: 				}
tikhomirov@530: 				header.putInt(version);
tikhomirov@530: 				header.putInt(0);
tikhomirov@530: 			} else {
tikhomirov@530: 				header.putLong(offset << 16);
tikhomirov@530: 			}
tikhomirov@530: 			header.putInt(compressedLength);
tikhomirov@530: 			header.putInt(length);
tikhomirov@530: 			header.putInt(baseRev);
tikhomirov@530: 			header.putInt(linkRev);
tikhomirov@530: 			header.putInt(p1);
tikhomirov@530: 			header.putInt(p2);
tikhomirov@534: 			header.put(nodeid);
tikhomirov@530: 			// assume 12 bytes left are zeros
tikhomirov@534: 			out.write(header.array(), 0, header.capacity());
tikhomirov@530: 
tikhomirov@530: 			// regardless whether it's inline or separate data,
tikhomirov@530: 			// offset field always represent cumulative compressedLength 
tikhomirov@530: 			// (while offset in the index file with inline==true differs by n*sizeof(header), where n is entry's position in the file) 
tikhomirov@530: 			offset += compressedLength;
tikhomirov@530: 		}
tikhomirov@534: 		
tikhomirov@534: 		public int serializeLength() {
tikhomirov@534: 			return header.capacity();
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	private final DigestHelper dh = new DigestHelper();
tikhomirov@534: 	private final RevlogCompressor revlogDataZip;
tikhomirov@534: 	
tikhomirov@534: 	
tikhomirov@534: 	public RevlogStreamWriter(SessionContext ctx, RevlogStream stream) {
tikhomirov@534: 		revlogDataZip = new RevlogCompressor(ctx);
tikhomirov@530: 	}
tikhomirov@530: 	
tikhomirov@534: 	private int lastEntryBase, lastEntryIndex;
tikhomirov@534: 	private byte[] lastEntryContent;
tikhomirov@534: 	private Nodeid lastEntryRevision;
tikhomirov@534: 	private IntMap<Nodeid> revisionCache = new IntMap<Nodeid>(32);
tikhomirov@533: 	
tikhomirov@533: 	public void addRevision(byte[] content, int linkRevision, int p1, int p2) {
tikhomirov@534: 		int revCount = revlogStream.revisionCount();
tikhomirov@534: 		lastEntryIndex = revCount == 0 ? NO_REVISION : revCount - 1;
tikhomirov@534: 		populateLastEntry();
tikhomirov@534: 		//
tikhomirov@533: 		PatchGenerator pg = new PatchGenerator();
tikhomirov@534: 		Patch patch = pg.delta(lastEntryContent, content);
tikhomirov@534: 		int patchSerializedLength = patch.serializedLength();
tikhomirov@534: 		
tikhomirov@534: 		final boolean writeComplete = preferCompleteOverPatch(patchSerializedLength, content.length);
tikhomirov@534: 		DataSerializer.DataSource dataSource = writeComplete ? new DataSerializer.ByteArrayDataSource(content) : patch.new PatchDataSource();
tikhomirov@534: 		revlogDataZip.reset(dataSource);
tikhomirov@534: 		final int compressedLen;
tikhomirov@534: 		final boolean useUncompressedData = preferCompressedOverComplete(revlogDataZip.getCompressedLength(), dataSource.serializeLength());
tikhomirov@534: 		if (useUncompressedData) {
tikhomirov@534: 			// compression wasn't too effective,
tikhomirov@534: 			compressedLen = dataSource.serializeLength() + 1 /*1 byte for 'u' - uncompressed prefix byte*/;
tikhomirov@534: 		} else {
tikhomirov@534: 			compressedLen= revlogDataZip.getCompressedLength();
tikhomirov@534: 		}
tikhomirov@534: 		//
tikhomirov@534: 		Nodeid p1Rev = revision(p1);
tikhomirov@534: 		Nodeid p2Rev = revision(p2);
tikhomirov@534: 		byte[] revisionNodeidBytes = dh.sha1(p1Rev, p2Rev, content).asBinary();
tikhomirov@534: 		//
tikhomirov@534: 
tikhomirov@534: 		DataSerializer indexFile, dataFile, activeFile;
tikhomirov@534: 		indexFile = dataFile = activeFile = null;
tikhomirov@534: 		try {
tikhomirov@534: 			//
tikhomirov@534: 			activeFile = indexFile = revlogStream.getIndexStreamWriter();
tikhomirov@534: 			final boolean isInlineData = revlogStream.isInlineData();
tikhomirov@534: 			HeaderWriter revlogHeader = new HeaderWriter(isInlineData);
tikhomirov@534: 			revlogHeader.length(content.length, compressedLen);
tikhomirov@534: 			revlogHeader.nodeid(revisionNodeidBytes);
tikhomirov@534: 			revlogHeader.linkRevision(linkRevision);
tikhomirov@534: 			revlogHeader.parents(p1, p2);
tikhomirov@534: 			revlogHeader.baseRevision(writeComplete ? lastEntryIndex+1 : lastEntryBase);
tikhomirov@534: 			//
tikhomirov@534: 			revlogHeader.serialize(indexFile);
tikhomirov@534: 			
tikhomirov@534: 			if (isInlineData) {
tikhomirov@534: 				dataFile = indexFile;
tikhomirov@534: 			} else {
tikhomirov@534: 				dataFile = revlogStream.getDataStreamWriter();
tikhomirov@534: 			}
tikhomirov@534: 			activeFile = dataFile;
tikhomirov@534: 			if (useUncompressedData) {
tikhomirov@534: 				dataFile.writeByte((byte) 'u');
tikhomirov@534: 				dataSource.serialize(dataFile);
tikhomirov@534: 			} else {
tikhomirov@534: 				int actualCompressedLenWritten = revlogDataZip.writeCompressedData(dataFile);
tikhomirov@534: 				if (actualCompressedLenWritten != compressedLen) {
tikhomirov@534: 					throw new HgInvalidStateException(String.format("Expected %d bytes of compressed data, but actually wrote %d in %s", compressedLen, actualCompressedLenWritten, revlogStream.getDataFileName()));
tikhomirov@534: 				}
tikhomirov@534: 			}
tikhomirov@534: 			
tikhomirov@534: 			lastEntryContent = content;
tikhomirov@534: 			lastEntryBase = revlogHeader.baseRevision();
tikhomirov@534: 			lastEntryIndex++;
tikhomirov@534: 			lastEntryRevision = Nodeid.fromBinary(revisionNodeidBytes, 0);
tikhomirov@534: 			revisionCache.put(lastEntryIndex, lastEntryRevision);
tikhomirov@534: 		} catch (IOException ex) {
tikhomirov@534: 			String m = String.format("Failed to write revision %d", lastEntryIndex+1, null);
tikhomirov@534: 			HgInvalidControlFileException t = new HgInvalidControlFileException(m, ex, null);
tikhomirov@534: 			if (activeFile == dataFile) {
tikhomirov@534: 				throw revlogStream.initWithDataFile(t);
tikhomirov@534: 			} else {
tikhomirov@534: 				throw revlogStream.initWithIndexFile(t);
tikhomirov@534: 			}
tikhomirov@534: 		} finally {
tikhomirov@534: 			indexFile.done();
tikhomirov@534: 			if (dataFile != null && dataFile != indexFile) {
tikhomirov@534: 				dataFile.done();
tikhomirov@534: 			}
tikhomirov@534: 		}
tikhomirov@533: 	}
tikhomirov@533: 	
tikhomirov@534: 	private RevlogStream revlogStream;
tikhomirov@534: 	private Nodeid revision(int revisionIndex) {
tikhomirov@534: 		if (revisionIndex == NO_REVISION) {
tikhomirov@534: 			return Nodeid.NULL;
tikhomirov@534: 		}
tikhomirov@534: 		Nodeid n = revisionCache.get(revisionIndex);
tikhomirov@534: 		if (n == null) {
tikhomirov@534: 			n = Nodeid.fromBinary(revlogStream.nodeid(revisionIndex), 0);
tikhomirov@534: 			revisionCache.put(revisionIndex, n);
tikhomirov@534: 		}
tikhomirov@534: 		return n;
tikhomirov@534: 	}
tikhomirov@534: 	
tikhomirov@534: 	private void populateLastEntry() throws HgInvalidControlFileException {
tikhomirov@534: 		if (lastEntryIndex != NO_REVISION && lastEntryContent == null) {
tikhomirov@534: 			assert lastEntryIndex >= 0;
tikhomirov@534: 			final IOException[] failure = new IOException[1];
tikhomirov@534: 			revlogStream.iterate(lastEntryIndex, lastEntryIndex, true, new RevlogStream.Inspector() {
tikhomirov@534: 				
tikhomirov@534: 				public void next(int revisionIndex, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[] nodeid, DataAccess data) {
tikhomirov@534: 					try {
tikhomirov@534: 						lastEntryBase = baseRevision;
tikhomirov@534: 						lastEntryRevision = Nodeid.fromBinary(nodeid, 0);
tikhomirov@534: 						lastEntryContent = data.byteArray();
tikhomirov@534: 					} catch (IOException ex) {
tikhomirov@534: 						failure[0] = ex;
tikhomirov@534: 					}
tikhomirov@534: 				}
tikhomirov@534: 			});
tikhomirov@534: 			if (failure[0] != null) {
tikhomirov@534: 				String m = String.format("Failed to get content of most recent revision %d", lastEntryIndex);
tikhomirov@534: 				throw revlogStream.initWithDataFile(new HgInvalidControlFileException(m, failure[0], null));
tikhomirov@534: 			}
tikhomirov@534: 		}
tikhomirov@534: 	}
tikhomirov@534: 	
tikhomirov@534: 	public static boolean preferCompleteOverPatch(int patchLength, int fullContentLength) {
tikhomirov@534: 		return !decideWorthEffort(patchLength, fullContentLength);
tikhomirov@534: 	}
tikhomirov@534: 	
tikhomirov@534: 	public static boolean preferCompressedOverComplete(int compressedLen, int fullContentLength) {
tikhomirov@534: 		if (compressedLen <= 0) { // just in case, meaningless otherwise
tikhomirov@534: 			return false;
tikhomirov@534: 		}
tikhomirov@534: 		return decideWorthEffort(compressedLen, fullContentLength);
tikhomirov@534: 	}
tikhomirov@534: 
tikhomirov@534: 	// true if length obtained with effort is worth it 
tikhomirov@534: 	private static boolean decideWorthEffort(int lengthWithExtraEffort, int lengthWithoutEffort) {
tikhomirov@534: 		return lengthWithExtraEffort < (/* 3/4 of original */lengthWithoutEffort - (lengthWithoutEffort >>> 2));
tikhomirov@530: 	}
tikhomirov@530: }