DfsPackFile.java
- /*
- * Copyright (C) 2008-2011, Google Inc.
- * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
- * Copyright (C) 2006-2008, 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.internal.storage.dfs;
- import static org.eclipse.jgit.internal.storage.dfs.DfsObjDatabase.PackSource.UNREACHABLE_GARBAGE;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.BITMAP_INDEX;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.INDEX;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.PACK;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.REVERSE_INDEX;
- import java.io.BufferedInputStream;
- import java.io.EOFException;
- import java.io.IOException;
- import java.io.InputStream;
- import java.nio.ByteBuffer;
- import java.nio.channels.Channels;
- import java.text.MessageFormat;
- import java.util.Set;
- import java.util.concurrent.atomic.AtomicBoolean;
- import java.util.zip.CRC32;
- import java.util.zip.DataFormatException;
- import java.util.zip.Inflater;
- import org.eclipse.jgit.errors.CorruptObjectException;
- import org.eclipse.jgit.errors.LargeObjectException;
- import org.eclipse.jgit.errors.MissingObjectException;
- import org.eclipse.jgit.errors.PackInvalidException;
- import org.eclipse.jgit.errors.StoredObjectRepresentationNotAvailableException;
- import org.eclipse.jgit.internal.JGitText;
- import org.eclipse.jgit.internal.storage.file.PackBitmapIndex;
- import org.eclipse.jgit.internal.storage.file.PackIndex;
- import org.eclipse.jgit.internal.storage.file.PackReverseIndex;
- import org.eclipse.jgit.internal.storage.pack.BinaryDelta;
- import org.eclipse.jgit.internal.storage.pack.PackOutputStream;
- import org.eclipse.jgit.internal.storage.pack.StoredObjectRepresentation;
- import org.eclipse.jgit.lib.AbbreviatedObjectId;
- import org.eclipse.jgit.lib.AnyObjectId;
- import org.eclipse.jgit.lib.Constants;
- import org.eclipse.jgit.lib.ObjectId;
- import org.eclipse.jgit.lib.ObjectLoader;
- import org.eclipse.jgit.lib.Repository;
- import org.eclipse.jgit.util.LongList;
- /**
- * A Git version 2 pack file representation. A pack file contains Git objects in
- * delta packed format yielding high compression of lots of object where some
- * objects are similar.
- */
- public final class DfsPackFile extends BlockBasedFile {
- private static final int REC_SIZE = Constants.OBJECT_ID_LENGTH + 8;
- private static final long REF_POSITION = 0;
- /** Index mapping {@link ObjectId} to position within the pack stream. */
- private volatile PackIndex index;
- /** Reverse version of {@link #index} mapping position to {@link ObjectId}. */
- private volatile PackReverseIndex reverseIndex;
- /** Index of compressed bitmap mapping entire object graph. */
- private volatile PackBitmapIndex bitmapIndex;
- /**
- * Objects we have tried to read, and discovered to be corrupt.
- * <p>
- * The list is allocated after the first corruption is found, and filled in
- * as more entries are discovered. Typically this list is never used, as
- * pack files do not usually contain corrupt objects.
- */
- private volatile LongList corruptObjects;
- /** Lock for {@link #corruptObjects}. */
- private final Object corruptObjectsLock = new Object();
- /**
- * Construct a reader for an existing, packfile.
- *
- * @param cache
- * cache that owns the pack data.
- * @param desc
- * description of the pack within the DFS.
- */
- DfsPackFile(DfsBlockCache cache, DfsPackDescription desc) {
- super(cache, desc, PACK);
- int bs = desc.getBlockSize(PACK);
- if (bs > 0) {
- setBlockSize(bs);
- }
- long sz = desc.getFileSize(PACK);
- length = sz > 0 ? sz : -1;
- }
- /**
- * Get description that was originally used to configure this pack file.
- *
- * @return description that was originally used to configure this pack file.
- */
- public DfsPackDescription getPackDescription() {
- return desc;
- }
- /**
- * Whether the pack index file is loaded and cached in memory.
- *
- * @return whether the pack index file is loaded and cached in memory.
- */
- public boolean isIndexLoaded() {
- return index != null;
- }
- void setPackIndex(PackIndex idx) {
- long objCnt = idx.getObjectCount();
- int recSize = Constants.OBJECT_ID_LENGTH + 8;
- long sz = objCnt * recSize;
- cache.putRef(desc.getStreamKey(INDEX), sz, idx);
- index = idx;
- }
- /**
- * Get the PackIndex for this PackFile.
- *
- * @param ctx
- * reader context to support reading from the backing store if
- * the index is not already loaded in memory.
- * @return the PackIndex.
- * @throws java.io.IOException
- * the pack index is not available, or is corrupt.
- */
- public PackIndex getPackIndex(DfsReader ctx) throws IOException {
- return idx(ctx);
- }
- private PackIndex idx(DfsReader ctx) throws IOException {
- if (index != null) {
- return index;
- }
- if (invalid) {
- throw new PackInvalidException(getFileName(), invalidatingCause);
- }
- Repository.getGlobalListenerList()
- .dispatch(new BeforeDfsPackIndexLoadedEvent(this));
- try {
- DfsStreamKey idxKey = desc.getStreamKey(INDEX);
- AtomicBoolean cacheHit = new AtomicBoolean(true);
- DfsBlockCache.Ref<PackIndex> idxref = cache.getOrLoadRef(idxKey,
- REF_POSITION, () -> {
- cacheHit.set(false);
- return loadPackIndex(ctx, idxKey);
- });
- if (cacheHit.get()) {
- ctx.stats.idxCacheHit++;
- }
- PackIndex idx = idxref.get();
- if (index == null && idx != null) {
- index = idx;
- }
- return index;
- } catch (IOException e) {
- invalid = true;
- invalidatingCause = e;
- throw e;
- }
- }
- final boolean isGarbage() {
- return desc.getPackSource() == UNREACHABLE_GARBAGE;
- }
- /**
- * Get the BitmapIndex for this PackFile.
- *
- * @param ctx
- * reader context to support reading from the backing store if
- * the index is not already loaded in memory.
- * @return the BitmapIndex.
- * @throws java.io.IOException
- * the bitmap index is not available, or is corrupt.
- */
- public PackBitmapIndex getBitmapIndex(DfsReader ctx) throws IOException {
- if (invalid || isGarbage() || !desc.hasFileExt(BITMAP_INDEX)) {
- return null;
- }
- if (bitmapIndex != null) {
- return bitmapIndex;
- }
- DfsStreamKey bitmapKey = desc.getStreamKey(BITMAP_INDEX);
- AtomicBoolean cacheHit = new AtomicBoolean(true);
- DfsBlockCache.Ref<PackBitmapIndex> idxref = cache
- .getOrLoadRef(bitmapKey, REF_POSITION, () -> {
- cacheHit.set(false);
- return loadBitmapIndex(ctx, bitmapKey);
- });
- if (cacheHit.get()) {
- ctx.stats.bitmapCacheHit++;
- }
- PackBitmapIndex bmidx = idxref.get();
- if (bitmapIndex == null && bmidx != null) {
- bitmapIndex = bmidx;
- }
- return bitmapIndex;
- }
- PackReverseIndex getReverseIdx(DfsReader ctx) throws IOException {
- if (reverseIndex != null) {
- return reverseIndex;
- }
- PackIndex idx = idx(ctx);
- DfsStreamKey revKey = desc.getStreamKey(REVERSE_INDEX);
- AtomicBoolean cacheHit = new AtomicBoolean(true);
- DfsBlockCache.Ref<PackReverseIndex> revref = cache.getOrLoadRef(revKey,
- REF_POSITION, () -> {
- cacheHit.set(false);
- return loadReverseIdx(ctx, revKey, idx);
- });
- if (cacheHit.get()) {
- ctx.stats.ridxCacheHit++;
- }
- PackReverseIndex revidx = revref.get();
- if (reverseIndex == null && revidx != null) {
- reverseIndex = revidx;
- }
- return reverseIndex;
- }
- /**
- * Check if an object is stored within this pack.
- *
- * @param ctx
- * reader context to support reading from the backing store if
- * the index is not already loaded in memory.
- * @param id
- * object to be located.
- * @return true if the object exists in this pack; false if it does not.
- * @throws java.io.IOException
- * the pack index is not available, or is corrupt.
- */
- public boolean hasObject(DfsReader ctx, AnyObjectId id) throws IOException {
- final long offset = idx(ctx).findOffset(id);
- return 0 < offset && !isCorrupt(offset);
- }
- /**
- * Get an object from this pack.
- *
- * @param ctx
- * temporary working space associated with the calling thread.
- * @param id
- * the object to obtain from the pack. Must not be null.
- * @return the object loader for the requested object if it is contained in
- * this pack; null if the object was not found.
- * @throws IOException
- * the pack file or the index could not be read.
- */
- ObjectLoader get(DfsReader ctx, AnyObjectId id)
- throws IOException {
- long offset = idx(ctx).findOffset(id);
- return 0 < offset && !isCorrupt(offset) ? load(ctx, offset) : null;
- }
- long findOffset(DfsReader ctx, AnyObjectId id) throws IOException {
- return idx(ctx).findOffset(id);
- }
- void resolve(DfsReader ctx, Set<ObjectId> matches, AbbreviatedObjectId id,
- int matchLimit) throws IOException {
- idx(ctx).resolve(matches, id, matchLimit);
- }
- /**
- * Obtain the total number of objects available in this pack. This method
- * relies on pack index, giving number of effectively available objects.
- *
- * @param ctx
- * current reader for the calling thread.
- * @return number of objects in index of this pack, likewise in this pack
- * @throws IOException
- * the index file cannot be loaded into memory.
- */
- long getObjectCount(DfsReader ctx) throws IOException {
- return idx(ctx).getObjectCount();
- }
- private byte[] decompress(long position, int sz, DfsReader ctx)
- throws IOException, DataFormatException {
- byte[] dstbuf;
- try {
- dstbuf = new byte[sz];
- } catch (OutOfMemoryError noMemory) {
- // The size may be larger than our heap allows, return null to
- // let the caller know allocation isn't possible and it should
- // use the large object streaming approach instead.
- //
- // For example, this can occur when sz is 640 MB, and JRE
- // maximum heap size is only 256 MB. Even if the JRE has
- // 200 MB free, it cannot allocate a 640 MB byte array.
- return null;
- }
- if (ctx.inflate(this, position, dstbuf, false) != sz) {
- throw new EOFException(MessageFormat.format(
- JGitText.get().shortCompressedStreamAt,
- Long.valueOf(position)));
- }
- return dstbuf;
- }
- void copyPackAsIs(PackOutputStream out, DfsReader ctx) throws IOException {
- // If the length hasn't been determined yet, pin to set it.
- if (length == -1) {
- ctx.pin(this, 0);
- ctx.unpin();
- }
- try (ReadableChannel rc = ctx.db.openFile(desc, PACK)) {
- int sz = ctx.getOptions().getStreamPackBufferSize();
- if (sz > 0) {
- rc.setReadAheadBytes(sz);
- }
- if (cache.shouldCopyThroughCache(length)) {
- copyPackThroughCache(out, ctx, rc);
- } else {
- copyPackBypassCache(out, rc);
- }
- }
- }
- private void copyPackThroughCache(PackOutputStream out, DfsReader ctx,
- ReadableChannel rc) throws IOException {
- long position = 12;
- long remaining = length - (12 + 20);
- while (0 < remaining) {
- DfsBlock b = cache.getOrLoad(this, position, ctx, () -> rc);
- int ptr = (int) (position - b.start);
- if (b.size() <= ptr) {
- throw packfileIsTruncated();
- }
- int n = (int) Math.min(b.size() - ptr, remaining);
- b.write(out, position, n);
- position += n;
- remaining -= n;
- }
- }
- private long copyPackBypassCache(PackOutputStream out, ReadableChannel rc)
- throws IOException {
- ByteBuffer buf = newCopyBuffer(out, rc);
- long position = 12;
- long remaining = length - (12 + 20);
- boolean packHeadSkipped = false;
- while (0 < remaining) {
- DfsBlock b = cache.get(key, alignToBlock(position));
- if (b != null) {
- int ptr = (int) (position - b.start);
- if (b.size() <= ptr) {
- throw packfileIsTruncated();
- }
- int n = (int) Math.min(b.size() - ptr, remaining);
- b.write(out, position, n);
- position += n;
- remaining -= n;
- rc.position(position);
- packHeadSkipped = true;
- continue;
- }
- // Need to skip the 'PACK' header for the first read
- int ptr = packHeadSkipped ? 0 : 12;
- buf.position(0);
- int bufLen = read(rc, buf);
- if (bufLen <= ptr) {
- throw packfileIsTruncated();
- }
- int n = (int) Math.min(bufLen - ptr, remaining);
- out.write(buf.array(), ptr, n);
- position += n;
- remaining -= n;
- packHeadSkipped = true;
- }
- return position;
- }
- private ByteBuffer newCopyBuffer(PackOutputStream out, ReadableChannel rc) {
- int bs = blockSize(rc);
- byte[] copyBuf = out.getCopyBuffer();
- if (bs > copyBuf.length) {
- copyBuf = new byte[bs];
- }
- return ByteBuffer.wrap(copyBuf, 0, bs);
- }
- void copyAsIs(PackOutputStream out, DfsObjectToPack src,
- boolean validate, DfsReader ctx) throws IOException,
- StoredObjectRepresentationNotAvailableException {
- final CRC32 crc1 = validate ? new CRC32() : null;
- final CRC32 crc2 = validate ? new CRC32() : null;
- final byte[] buf = out.getCopyBuffer();
- // Rip apart the header so we can discover the size.
- //
- try {
- readFully(src.offset, buf, 0, 20, ctx);
- } catch (IOException ioError) {
- throw new StoredObjectRepresentationNotAvailableException(ioError);
- }
- int c = buf[0] & 0xff;
- final int typeCode = (c >> 4) & 7;
- long inflatedLength = c & 15;
- int shift = 4;
- int headerCnt = 1;
- while ((c & 0x80) != 0) {
- c = buf[headerCnt++] & 0xff;
- inflatedLength += ((long) (c & 0x7f)) << shift;
- shift += 7;
- }
- if (typeCode == Constants.OBJ_OFS_DELTA) {
- do {
- c = buf[headerCnt++] & 0xff;
- } while ((c & 128) != 0);
- if (validate) {
- assert(crc1 != null && crc2 != null);
- crc1.update(buf, 0, headerCnt);
- crc2.update(buf, 0, headerCnt);
- }
- } else if (typeCode == Constants.OBJ_REF_DELTA) {
- if (validate) {
- assert(crc1 != null && crc2 != null);
- crc1.update(buf, 0, headerCnt);
- crc2.update(buf, 0, headerCnt);
- }
- readFully(src.offset + headerCnt, buf, 0, 20, ctx);
- if (validate) {
- assert(crc1 != null && crc2 != null);
- crc1.update(buf, 0, 20);
- crc2.update(buf, 0, 20);
- }
- headerCnt += 20;
- } else if (validate) {
- assert(crc1 != null && crc2 != null);
- crc1.update(buf, 0, headerCnt);
- crc2.update(buf, 0, headerCnt);
- }
- final long dataOffset = src.offset + headerCnt;
- final long dataLength = src.length;
- final long expectedCRC;
- final DfsBlock quickCopy;
- // Verify the object isn't corrupt before sending. If it is,
- // we report it missing instead.
- //
- try {
- quickCopy = ctx.quickCopy(this, dataOffset, dataLength);
- if (validate && idx(ctx).hasCRC32Support()) {
- assert(crc1 != null);
- // Index has the CRC32 code cached, validate the object.
- //
- expectedCRC = idx(ctx).findCRC32(src);
- if (quickCopy != null) {
- quickCopy.crc32(crc1, dataOffset, (int) dataLength);
- } else {
- long pos = dataOffset;
- long cnt = dataLength;
- while (cnt > 0) {
- final int n = (int) Math.min(cnt, buf.length);
- readFully(pos, buf, 0, n, ctx);
- crc1.update(buf, 0, n);
- pos += n;
- cnt -= n;
- }
- }
- if (crc1.getValue() != expectedCRC) {
- setCorrupt(src.offset);
- throw new CorruptObjectException(MessageFormat.format(
- JGitText.get().objectAtHasBadZlibStream,
- Long.valueOf(src.offset), getFileName()));
- }
- } else if (validate) {
- assert(crc1 != null);
- // We don't have a CRC32 code in the index, so compute it
- // now while inflating the raw data to get zlib to tell us
- // whether or not the data is safe.
- //
- Inflater inf = ctx.inflater();
- byte[] tmp = new byte[1024];
- if (quickCopy != null) {
- quickCopy.check(inf, tmp, dataOffset, (int) dataLength);
- } else {
- long pos = dataOffset;
- long cnt = dataLength;
- while (cnt > 0) {
- final int n = (int) Math.min(cnt, buf.length);
- readFully(pos, buf, 0, n, ctx);
- crc1.update(buf, 0, n);
- inf.setInput(buf, 0, n);
- while (inf.inflate(tmp, 0, tmp.length) > 0) {
- continue;
- }
- pos += n;
- cnt -= n;
- }
- }
- if (!inf.finished() || inf.getBytesRead() != dataLength) {
- setCorrupt(src.offset);
- throw new EOFException(MessageFormat.format(
- JGitText.get().shortCompressedStreamAt,
- Long.valueOf(src.offset)));
- }
- expectedCRC = crc1.getValue();
- } else {
- expectedCRC = -1;
- }
- } catch (DataFormatException dataFormat) {
- setCorrupt(src.offset);
- CorruptObjectException corruptObject = new CorruptObjectException(
- MessageFormat.format(
- JGitText.get().objectAtHasBadZlibStream,
- Long.valueOf(src.offset), getFileName()),
- dataFormat);
- throw new StoredObjectRepresentationNotAvailableException(
- corruptObject);
- } catch (IOException ioError) {
- throw new StoredObjectRepresentationNotAvailableException(ioError);
- }
- if (quickCopy != null) {
- // The entire object fits into a single byte array window slice,
- // and we have it pinned. Write this out without copying.
- //
- out.writeHeader(src, inflatedLength);
- quickCopy.write(out, dataOffset, (int) dataLength);
- } else if (dataLength <= buf.length) {
- // Tiny optimization: Lots of objects are very small deltas or
- // deflated commits that are likely to fit in the copy buffer.
- //
- if (!validate) {
- long pos = dataOffset;
- long cnt = dataLength;
- while (cnt > 0) {
- final int n = (int) Math.min(cnt, buf.length);
- readFully(pos, buf, 0, n, ctx);
- pos += n;
- cnt -= n;
- }
- }
- out.writeHeader(src, inflatedLength);
- out.write(buf, 0, (int) dataLength);
- } else {
- // Now we are committed to sending the object. As we spool it out,
- // check its CRC32 code to make sure there wasn't corruption between
- // the verification we did above, and us actually outputting it.
- //
- out.writeHeader(src, inflatedLength);
- long pos = dataOffset;
- long cnt = dataLength;
- while (cnt > 0) {
- final int n = (int) Math.min(cnt, buf.length);
- readFully(pos, buf, 0, n, ctx);
- if (validate) {
- assert(crc2 != null);
- crc2.update(buf, 0, n);
- }
- out.write(buf, 0, n);
- pos += n;
- cnt -= n;
- }
- if (validate) {
- assert(crc2 != null);
- if (crc2.getValue() != expectedCRC) {
- throw new CorruptObjectException(MessageFormat.format(
- JGitText.get().objectAtHasBadZlibStream,
- Long.valueOf(src.offset), getFileName()));
- }
- }
- }
- }
- private IOException packfileIsTruncated() {
- invalid = true;
- IOException exc = new IOException(MessageFormat.format(
- JGitText.get().packfileIsTruncated, getFileName()));
- invalidatingCause = exc;
- return exc;
- }
- private void readFully(long position, byte[] dstbuf, int dstoff, int cnt,
- DfsReader ctx) throws IOException {
- while (cnt > 0) {
- int copied = ctx.copy(this, position, dstbuf, dstoff, cnt);
- if (copied == 0) {
- throw new EOFException();
- }
- position += copied;
- dstoff += copied;
- cnt -= copied;
- }
- }
- ObjectLoader load(DfsReader ctx, long pos)
- throws IOException {
- try {
- final byte[] ib = ctx.tempId;
- Delta delta = null;
- byte[] data = null;
- int type = Constants.OBJ_BAD;
- boolean cached = false;
- SEARCH: for (;;) {
- readFully(pos, ib, 0, 20, ctx);
- int c = ib[0] & 0xff;
- final int typeCode = (c >> 4) & 7;
- long sz = c & 15;
- int shift = 4;
- int p = 1;
- while ((c & 0x80) != 0) {
- c = ib[p++] & 0xff;
- sz += ((long) (c & 0x7f)) << shift;
- shift += 7;
- }
- switch (typeCode) {
- case Constants.OBJ_COMMIT:
- case Constants.OBJ_TREE:
- case Constants.OBJ_BLOB:
- case Constants.OBJ_TAG: {
- if (delta != null) {
- data = decompress(pos + p, (int) sz, ctx);
- type = typeCode;
- break SEARCH;
- }
- if (sz < ctx.getStreamFileThreshold()) {
- data = decompress(pos + p, (int) sz, ctx);
- if (data != null) {
- return new ObjectLoader.SmallObject(typeCode, data);
- }
- }
- return new LargePackedWholeObject(typeCode, sz, pos, p, this, ctx.db);
- }
- case Constants.OBJ_OFS_DELTA: {
- c = ib[p++] & 0xff;
- long base = c & 127;
- while ((c & 128) != 0) {
- base += 1;
- c = ib[p++] & 0xff;
- base <<= 7;
- base += (c & 127);
- }
- base = pos - base;
- delta = new Delta(delta, pos, (int) sz, p, base);
- if (sz != delta.deltaSize) {
- break SEARCH;
- }
- DeltaBaseCache.Entry e = ctx.getDeltaBaseCache().get(key, base);
- if (e != null) {
- type = e.type;
- data = e.data;
- cached = true;
- break SEARCH;
- }
- pos = base;
- continue SEARCH;
- }
- case Constants.OBJ_REF_DELTA: {
- readFully(pos + p, ib, 0, 20, ctx);
- long base = findDeltaBase(ctx, ObjectId.fromRaw(ib));
- delta = new Delta(delta, pos, (int) sz, p + 20, base);
- if (sz != delta.deltaSize) {
- break SEARCH;
- }
- DeltaBaseCache.Entry e = ctx.getDeltaBaseCache().get(key, base);
- if (e != null) {
- type = e.type;
- data = e.data;
- cached = true;
- break SEARCH;
- }
- pos = base;
- continue SEARCH;
- }
- default:
- throw new IOException(MessageFormat.format(
- JGitText.get().unknownObjectType, Integer.valueOf(typeCode)));
- }
- }
- // At this point there is at least one delta to apply to data.
- // (Whole objects with no deltas to apply return early above.)
- if (data == null)
- throw new LargeObjectException();
- assert(delta != null);
- do {
- // Cache only the base immediately before desired object.
- if (cached) {
- cached = false;
- } else if (delta.next == null) {
- ctx.getDeltaBaseCache().put(key, delta.basePos, type, data);
- }
- pos = delta.deltaPos;
- byte[] cmds = decompress(pos + delta.hdrLen, delta.deltaSize, ctx);
- if (cmds == null) {
- data = null; // Discard base in case of OutOfMemoryError
- throw new LargeObjectException();
- }
- final long sz = BinaryDelta.getResultSize(cmds);
- if (Integer.MAX_VALUE <= sz) {
- throw new LargeObjectException.ExceedsByteArrayLimit();
- }
- final byte[] result;
- try {
- result = new byte[(int) sz];
- } catch (OutOfMemoryError tooBig) {
- data = null; // Discard base in case of OutOfMemoryError
- cmds = null;
- throw new LargeObjectException.OutOfMemory(tooBig);
- }
- BinaryDelta.apply(data, cmds, result);
- data = result;
- delta = delta.next;
- } while (delta != null);
- return new ObjectLoader.SmallObject(type, data);
- } catch (DataFormatException dfe) {
- throw new CorruptObjectException(
- MessageFormat.format(
- JGitText.get().objectAtHasBadZlibStream, Long.valueOf(pos),
- getFileName()),
- dfe);
- }
- }
- private long findDeltaBase(DfsReader ctx, ObjectId baseId)
- throws IOException, MissingObjectException {
- long ofs = idx(ctx).findOffset(baseId);
- if (ofs < 0) {
- throw new MissingObjectException(baseId,
- JGitText.get().missingDeltaBase);
- }
- return ofs;
- }
- private static class Delta {
- /** Child that applies onto this object. */
- final Delta next;
- /** Offset of the delta object. */
- final long deltaPos;
- /** Size of the inflated delta stream. */
- final int deltaSize;
- /** Total size of the delta's pack entry header (including base). */
- final int hdrLen;
- /** Offset of the base object this delta applies onto. */
- final long basePos;
- Delta(Delta next, long ofs, int sz, int hdrLen, long baseOffset) {
- this.next = next;
- this.deltaPos = ofs;
- this.deltaSize = sz;
- this.hdrLen = hdrLen;
- this.basePos = baseOffset;
- }
- }
- byte[] getDeltaHeader(DfsReader wc, long pos)
- throws IOException, DataFormatException {
- // The delta stream starts as two variable length integers. If we
- // assume they are 64 bits each, we need 16 bytes to encode them,
- // plus 2 extra bytes for the variable length overhead. So 18 is
- // the longest delta instruction header.
- //
- final byte[] hdr = new byte[32];
- wc.inflate(this, pos, hdr, true /* header only */);
- return hdr;
- }
- int getObjectType(DfsReader ctx, long pos) throws IOException {
- final byte[] ib = ctx.tempId;
- for (;;) {
- readFully(pos, ib, 0, 20, ctx);
- int c = ib[0] & 0xff;
- final int type = (c >> 4) & 7;
- switch (type) {
- case Constants.OBJ_COMMIT:
- case Constants.OBJ_TREE:
- case Constants.OBJ_BLOB:
- case Constants.OBJ_TAG:
- return type;
- case Constants.OBJ_OFS_DELTA: {
- int p = 1;
- while ((c & 0x80) != 0) {
- c = ib[p++] & 0xff;
- }
- c = ib[p++] & 0xff;
- long ofs = c & 127;
- while ((c & 128) != 0) {
- ofs += 1;
- c = ib[p++] & 0xff;
- ofs <<= 7;
- ofs += (c & 127);
- }
- pos = pos - ofs;
- continue;
- }
- case Constants.OBJ_REF_DELTA: {
- int p = 1;
- while ((c & 0x80) != 0) {
- c = ib[p++] & 0xff;
- }
- readFully(pos + p, ib, 0, 20, ctx);
- pos = findDeltaBase(ctx, ObjectId.fromRaw(ib));
- continue;
- }
- default:
- throw new IOException(MessageFormat.format(
- JGitText.get().unknownObjectType, Integer.valueOf(type)));
- }
- }
- }
- long getObjectSize(DfsReader ctx, AnyObjectId id) throws IOException {
- final long offset = idx(ctx).findOffset(id);
- return 0 < offset ? getObjectSize(ctx, offset) : -1;
- }
- long getObjectSize(DfsReader ctx, long pos)
- throws IOException {
- final byte[] ib = ctx.tempId;
- readFully(pos, ib, 0, 20, ctx);
- int c = ib[0] & 0xff;
- final int type = (c >> 4) & 7;
- long sz = c & 15;
- int shift = 4;
- int p = 1;
- while ((c & 0x80) != 0) {
- c = ib[p++] & 0xff;
- sz += ((long) (c & 0x7f)) << shift;
- shift += 7;
- }
- long deltaAt;
- switch (type) {
- case Constants.OBJ_COMMIT:
- case Constants.OBJ_TREE:
- case Constants.OBJ_BLOB:
- case Constants.OBJ_TAG:
- return sz;
- case Constants.OBJ_OFS_DELTA:
- c = ib[p++] & 0xff;
- while ((c & 128) != 0) {
- c = ib[p++] & 0xff;
- }
- deltaAt = pos + p;
- break;
- case Constants.OBJ_REF_DELTA:
- deltaAt = pos + p + 20;
- break;
- default:
- throw new IOException(MessageFormat.format(
- JGitText.get().unknownObjectType, Integer.valueOf(type)));
- }
- try {
- return BinaryDelta.getResultSize(getDeltaHeader(ctx, deltaAt));
- } catch (DataFormatException dfe) {
- throw new CorruptObjectException(
- MessageFormat.format(
- JGitText.get().objectAtHasBadZlibStream, Long.valueOf(pos),
- getFileName()),
- dfe);
- }
- }
- void representation(DfsObjectRepresentation r, final long pos,
- DfsReader ctx, PackReverseIndex rev)
- throws IOException {
- r.offset = pos;
- final byte[] ib = ctx.tempId;
- readFully(pos, ib, 0, 20, ctx);
- int c = ib[0] & 0xff;
- int p = 1;
- final int typeCode = (c >> 4) & 7;
- while ((c & 0x80) != 0) {
- c = ib[p++] & 0xff;
- }
- long len = rev.findNextOffset(pos, length - 20) - pos;
- switch (typeCode) {
- case Constants.OBJ_COMMIT:
- case Constants.OBJ_TREE:
- case Constants.OBJ_BLOB:
- case Constants.OBJ_TAG:
- r.format = StoredObjectRepresentation.PACK_WHOLE;
- r.baseId = null;
- r.length = len - p;
- return;
- case Constants.OBJ_OFS_DELTA: {
- c = ib[p++] & 0xff;
- long ofs = c & 127;
- while ((c & 128) != 0) {
- ofs += 1;
- c = ib[p++] & 0xff;
- ofs <<= 7;
- ofs += (c & 127);
- }
- r.format = StoredObjectRepresentation.PACK_DELTA;
- r.baseId = rev.findObject(pos - ofs);
- r.length = len - p;
- return;
- }
- case Constants.OBJ_REF_DELTA: {
- readFully(pos + p, ib, 0, 20, ctx);
- r.format = StoredObjectRepresentation.PACK_DELTA;
- r.baseId = ObjectId.fromRaw(ib);
- r.length = len - p - 20;
- return;
- }
- default:
- throw new IOException(MessageFormat.format(
- JGitText.get().unknownObjectType, Integer.valueOf(typeCode)));
- }
- }
- boolean isCorrupt(long offset) {
- LongList list = corruptObjects;
- if (list == null) {
- return false;
- }
- synchronized (list) {
- return list.contains(offset);
- }
- }
- private void setCorrupt(long offset) {
- LongList list = corruptObjects;
- if (list == null) {
- synchronized (corruptObjectsLock) {
- list = corruptObjects;
- if (list == null) {
- list = new LongList();
- corruptObjects = list;
- }
- }
- }
- synchronized (list) {
- list.add(offset);
- }
- }
- private DfsBlockCache.Ref<PackIndex> loadPackIndex(
- DfsReader ctx, DfsStreamKey idxKey) throws IOException {
- try {
- ctx.stats.readIdx++;
- long start = System.nanoTime();
- try (ReadableChannel rc = ctx.db.openFile(desc, INDEX)) {
- InputStream in = Channels.newInputStream(rc);
- int wantSize = 8192;
- int bs = rc.blockSize();
- if (0 < bs && bs < wantSize) {
- bs = (wantSize / bs) * bs;
- } else if (bs <= 0) {
- bs = wantSize;
- }
- PackIndex idx = PackIndex.read(new BufferedInputStream(in, bs));
- ctx.stats.readIdxBytes += rc.position();
- index = idx;
- return new DfsBlockCache.Ref<>(
- idxKey,
- REF_POSITION,
- idx.getObjectCount() * REC_SIZE,
- idx);
- } finally {
- ctx.stats.readIdxMicros += elapsedMicros(start);
- }
- } catch (EOFException e) {
- throw new IOException(MessageFormat.format(
- DfsText.get().shortReadOfIndex,
- desc.getFileName(INDEX)), e);
- } catch (IOException e) {
- throw new IOException(MessageFormat.format(
- DfsText.get().cannotReadIndex,
- desc.getFileName(INDEX)), e);
- }
- }
- private DfsBlockCache.Ref<PackReverseIndex> loadReverseIdx(
- DfsReader ctx, DfsStreamKey revKey, PackIndex idx) {
- ctx.stats.readReverseIdx++;
- long start = System.nanoTime();
- PackReverseIndex revidx = new PackReverseIndex(idx);
- reverseIndex = revidx;
- ctx.stats.readReverseIdxMicros += elapsedMicros(start);
- return new DfsBlockCache.Ref<>(
- revKey,
- REF_POSITION,
- idx.getObjectCount() * 8,
- revidx);
- }
- private DfsBlockCache.Ref<PackBitmapIndex> loadBitmapIndex(DfsReader ctx,
- DfsStreamKey bitmapKey) throws IOException {
- ctx.stats.readBitmap++;
- long start = System.nanoTime();
- try (ReadableChannel rc = ctx.db.openFile(desc, BITMAP_INDEX)) {
- long size;
- PackBitmapIndex bmidx;
- try {
- InputStream in = Channels.newInputStream(rc);
- int wantSize = 8192;
- int bs = rc.blockSize();
- if (0 < bs && bs < wantSize) {
- bs = (wantSize / bs) * bs;
- } else if (bs <= 0) {
- bs = wantSize;
- }
- in = new BufferedInputStream(in, bs);
- bmidx = PackBitmapIndex.read(in, () -> idx(ctx),
- () -> getReverseIdx(ctx),
- ctx.getOptions().shouldLoadRevIndexInParallel());
- } finally {
- size = rc.position();
- ctx.stats.readBitmapIdxBytes += size;
- ctx.stats.readBitmapIdxMicros += elapsedMicros(start);
- }
- bitmapIndex = bmidx;
- return new DfsBlockCache.Ref<>(
- bitmapKey, REF_POSITION, size, bmidx);
- } catch (EOFException e) {
- throw new IOException(MessageFormat.format(
- DfsText.get().shortReadOfIndex,
- desc.getFileName(BITMAP_INDEX)), e);
- } catch (IOException e) {
- throw new IOException(MessageFormat.format(
- DfsText.get().cannotReadIndex,
- desc.getFileName(BITMAP_INDEX)), e);
- }
- }
- }