123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307 |
- /*
- * Copyright (C) 2008-2009, Google Inc.
- * Copyright (C) 2006-2008, Shawn O. Pearce <spearce@spearce.org>
- * 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.storage.file;
-
- import java.io.IOException;
- import java.util.Collection;
- import java.util.Collections;
- import java.util.HashSet;
- import java.util.List;
- import java.util.zip.DataFormatException;
- import java.util.zip.Inflater;
-
- import org.eclipse.jgit.errors.IncorrectObjectTypeException;
- import org.eclipse.jgit.errors.MissingObjectException;
- import org.eclipse.jgit.errors.StoredObjectRepresentationNotAvailableException;
- import org.eclipse.jgit.lib.AbbreviatedObjectId;
- import org.eclipse.jgit.lib.AnyObjectId;
- import org.eclipse.jgit.lib.Constants;
- import org.eclipse.jgit.lib.InflaterCache;
- import org.eclipse.jgit.lib.ObjectId;
- import org.eclipse.jgit.lib.ObjectLoader;
- import org.eclipse.jgit.lib.ObjectReader;
- import org.eclipse.jgit.lib.ProgressMonitor;
- import org.eclipse.jgit.revwalk.RevObject;
- import org.eclipse.jgit.storage.pack.CachedPack;
- import org.eclipse.jgit.storage.pack.ObjectReuseAsIs;
- import org.eclipse.jgit.storage.pack.ObjectToPack;
- import org.eclipse.jgit.storage.pack.PackOutputStream;
- import org.eclipse.jgit.storage.pack.PackWriter;
-
- /** Active handle to a ByteWindow. */
- final class WindowCursor extends ObjectReader implements ObjectReuseAsIs {
- /** Temporary buffer large enough for at least one raw object id. */
- final byte[] tempId = new byte[Constants.OBJECT_ID_LENGTH];
-
- private Inflater inf;
-
- private ByteWindow window;
-
- final FileObjectDatabase db;
-
- WindowCursor(FileObjectDatabase db) {
- this.db = db;
- }
-
- @Override
- public ObjectReader newReader() {
- return new WindowCursor(db);
- }
-
- @Override
- public Collection<ObjectId> resolve(AbbreviatedObjectId id)
- throws IOException {
- if (id.isComplete())
- return Collections.singleton(id.toObjectId());
- HashSet<ObjectId> matches = new HashSet<ObjectId>(4);
- db.resolve(matches, id);
- return matches;
- }
-
- public boolean has(AnyObjectId objectId) throws IOException {
- return db.has(objectId);
- }
-
- public ObjectLoader open(AnyObjectId objectId, int typeHint)
- throws MissingObjectException, IncorrectObjectTypeException,
- IOException {
- final ObjectLoader ldr = db.openObject(this, objectId);
- if (ldr == null) {
- if (typeHint == OBJ_ANY)
- throw new MissingObjectException(objectId.copy(), "unknown");
- throw new MissingObjectException(objectId.copy(), typeHint);
- }
- if (typeHint != OBJ_ANY && ldr.getType() != typeHint)
- throw new IncorrectObjectTypeException(objectId.copy(), typeHint);
- return ldr;
- }
-
- public long getObjectSize(AnyObjectId objectId, int typeHint)
- throws MissingObjectException, IncorrectObjectTypeException,
- IOException {
- long sz = db.getObjectSize(this, objectId);
- if (sz < 0) {
- if (typeHint == OBJ_ANY)
- throw new MissingObjectException(objectId.copy(), "unknown");
- throw new MissingObjectException(objectId.copy(), typeHint);
- }
- return sz;
- }
-
- public LocalObjectToPack newObjectToPack(RevObject obj) {
- return new LocalObjectToPack(obj);
- }
-
- public void selectObjectRepresentation(PackWriter packer,
- ProgressMonitor monitor, Iterable<ObjectToPack> objects)
- throws IOException, MissingObjectException {
- for (ObjectToPack otp : objects) {
- db.selectObjectRepresentation(packer, otp, this);
- monitor.update(1);
- }
- }
-
- public void copyObjectAsIs(PackOutputStream out, ObjectToPack otp)
- throws IOException, StoredObjectRepresentationNotAvailableException {
- LocalObjectToPack src = (LocalObjectToPack) otp;
- src.pack.copyAsIs(out, src, this);
- }
-
- public void writeObjects(PackOutputStream out, List<ObjectToPack> list)
- throws IOException {
- for (ObjectToPack otp : list)
- out.writeObject(otp);
- }
-
- @SuppressWarnings("unchecked")
- public Collection<CachedPack> getCachedPacks() throws IOException {
- return (Collection<CachedPack>) db.getCachedPacks();
- }
-
- /**
- * Copy bytes from the window to a caller supplied buffer.
- *
- * @param pack
- * the file the desired window is stored within.
- * @param position
- * position within the file to read from.
- * @param dstbuf
- * destination buffer to copy into.
- * @param dstoff
- * offset within <code>dstbuf</code> to start copying into.
- * @param cnt
- * number of bytes to copy. This value may exceed the number of
- * bytes remaining in the window starting at offset
- * <code>pos</code>.
- * @return number of bytes actually copied; this may be less than
- * <code>cnt</code> if <code>cnt</code> exceeded the number of bytes
- * available.
- * @throws IOException
- * this cursor does not match the provider or id and the proper
- * window could not be acquired through the provider's cache.
- */
- int copy(final PackFile pack, long position, final byte[] dstbuf,
- int dstoff, final int cnt) throws IOException {
- final long length = pack.length;
- int need = cnt;
- while (need > 0 && position < length) {
- pin(pack, position);
- final int r = window.copy(position, dstbuf, dstoff, need);
- position += r;
- dstoff += r;
- need -= r;
- }
- return cnt - need;
- }
-
- public void copyPackAsIs(PackOutputStream out, CachedPack pack)
- throws IOException {
- ((LocalCachedPack) pack).copyAsIs(out, this);
- }
-
- void copyPackAsIs(final PackFile pack, final PackOutputStream out,
- long position, long cnt) throws IOException {
- while (0 < cnt) {
- pin(pack, position);
-
- int ptr = (int) (position - window.start);
- int n = (int) Math.min(window.size() - ptr, cnt);
- window.write(out, position, n);
- position += n;
- cnt -= n;
- }
- }
-
- /**
- * Inflate a region of the pack starting at {@code position}.
- *
- * @param pack
- * the file the desired window is stored within.
- * @param position
- * position within the file to read from.
- * @param dstbuf
- * destination buffer the inflater should output decompressed
- * data to.
- * @param dstoff
- * current offset within <code>dstbuf</code> to inflate into.
- * @return updated <code>dstoff</code> based on the number of bytes
- * successfully inflated into <code>dstbuf</code>.
- * @throws IOException
- * this cursor does not match the provider or id and the proper
- * window could not be acquired through the provider's cache.
- * @throws DataFormatException
- * the inflater encountered an invalid chunk of data. Data
- * stream corruption is likely.
- */
- int inflate(final PackFile pack, long position, final byte[] dstbuf,
- int dstoff) throws IOException, DataFormatException {
- prepareInflater();
- pin(pack, position);
- position += window.setInput(position, inf);
- do {
- int n = inf.inflate(dstbuf, dstoff, dstbuf.length - dstoff);
- if (n == 0) {
- if (inf.needsInput()) {
- pin(pack, position);
- position += window.setInput(position, inf);
- } else if (inf.finished())
- return dstoff;
- else
- throw new DataFormatException();
- }
- dstoff += n;
- } while (dstoff < dstbuf.length);
- return dstoff;
- }
-
- ByteArrayWindow quickCopy(PackFile p, long pos, long cnt)
- throws IOException {
- pin(p, pos);
- if (window instanceof ByteArrayWindow
- && window.contains(p, pos + (cnt - 1)))
- return (ByteArrayWindow) window;
- return null;
- }
-
- Inflater inflater() {
- prepareInflater();
- return inf;
- }
-
- private void prepareInflater() {
- if (inf == null)
- inf = InflaterCache.get();
- else
- inf.reset();
- }
-
- void pin(final PackFile pack, final long position)
- throws IOException {
- final ByteWindow w = window;
- if (w == null || !w.contains(pack, position)) {
- // If memory is low, we may need what is in our window field to
- // be cleaned up by the GC during the get for the next window.
- // So we always clear it, even though we are just going to set
- // it again.
- //
- window = null;
- window = WindowCache.get(pack, position);
- }
- }
-
- int getStreamFileThreshold() {
- return WindowCache.getStreamFileThreshold();
- }
-
- /** Release the current window cursor. */
- public void release() {
- window = null;
- try {
- InflaterCache.release(inf);
- } finally {
- inf = null;
- }
- }
- }
|