123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664 |
- /*
- * Copyright (C) 2009, Google Inc. 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.file;
-
- import static java.nio.charset.StandardCharsets.UTF_8;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.INDEX;
- import static org.eclipse.jgit.internal.storage.pack.PackExt.PACK;
-
- import java.io.BufferedReader;
- import java.io.File;
- import java.io.FileNotFoundException;
- import java.io.IOException;
- import java.nio.file.Files;
- import java.text.MessageFormat;
- import java.util.ArrayList;
- import java.util.Collection;
- import java.util.Collections;
- import java.util.HashSet;
- import java.util.List;
- import java.util.Objects;
- import java.util.Set;
- import java.util.concurrent.atomic.AtomicReference;
-
- import org.eclipse.jgit.internal.JGitText;
- import org.eclipse.jgit.internal.storage.pack.ObjectToPack;
- import org.eclipse.jgit.internal.storage.pack.PackExt;
- import org.eclipse.jgit.internal.storage.pack.PackWriter;
- import org.eclipse.jgit.lib.AbbreviatedObjectId;
- import org.eclipse.jgit.lib.AnyObjectId;
- import org.eclipse.jgit.lib.Config;
- import org.eclipse.jgit.lib.Constants;
- import org.eclipse.jgit.lib.ObjectDatabase;
- import org.eclipse.jgit.lib.ObjectId;
- import org.eclipse.jgit.lib.ObjectLoader;
- import org.eclipse.jgit.lib.RepositoryCache;
- import org.eclipse.jgit.lib.RepositoryCache.FileKey;
- import org.eclipse.jgit.util.FS;
- import org.eclipse.jgit.util.FileUtils;
-
- /**
- * Traditional file system based {@link org.eclipse.jgit.lib.ObjectDatabase}.
- * <p>
- * This is the classical object database representation for a Git repository,
- * where objects are stored loose by hashing them into directories by their
- * {@link org.eclipse.jgit.lib.ObjectId}, or are stored in compressed containers
- * known as {@link org.eclipse.jgit.internal.storage.file.Pack}s.
- * <p>
- * Optionally an object database can reference one or more alternates; other
- * ObjectDatabase instances that are searched in addition to the current
- * database.
- * <p>
- * Databases are divided into two halves: a half that is considered to be fast
- * to search (the {@code PackFile}s), and a half that is considered to be slow
- * to search (loose objects). When alternates are present the fast half is fully
- * searched (recursively through all alternates) before the slow half is
- * considered.
- */
- public class ObjectDirectory extends FileObjectDatabase {
- /** Maximum number of candidates offered as resolutions of abbreviation. */
- private static final int RESOLVE_ABBREV_LIMIT = 256;
-
- private final AlternateHandle handle = new AlternateHandle(this);
-
- private final Config config;
-
- private final File objects;
-
- private final File infoDirectory;
-
- private final LooseObjects loose;
-
- private final PackDirectory packed;
-
- private final File preservedDirectory;
-
- private final File alternatesFile;
-
- private final FS fs;
-
- private final AtomicReference<AlternateHandle[]> alternates;
-
- private final File shallowFile;
-
- private FileSnapshot shallowFileSnapshot = FileSnapshot.DIRTY;
-
- private Set<ObjectId> shallowCommitsIds;
-
- /**
- * Initialize a reference to an on-disk object directory.
- *
- * @param cfg
- * configuration this directory consults for write settings.
- * @param dir
- * the location of the <code>objects</code> directory.
- * @param alternatePaths
- * a list of alternate object directories
- * @param fs
- * the file system abstraction which will be necessary to perform
- * certain file system operations.
- * @param shallowFile
- * file which contains IDs of shallow commits, null if shallow
- * commits handling should be turned off
- * @throws java.io.IOException
- * an alternate object cannot be opened.
- */
- public ObjectDirectory(final Config cfg, final File dir,
- File[] alternatePaths, FS fs, File shallowFile) throws IOException {
- config = cfg;
- objects = dir;
- infoDirectory = new File(objects, "info"); //$NON-NLS-1$
- File packDirectory = new File(objects, "pack"); //$NON-NLS-1$
- preservedDirectory = new File(packDirectory, "preserved"); //$NON-NLS-1$
- alternatesFile = new File(objects, Constants.INFO_ALTERNATES);
- loose = new LooseObjects(objects);
- packed = new PackDirectory(config, packDirectory);
- this.fs = fs;
- this.shallowFile = shallowFile;
-
- alternates = new AtomicReference<>();
- if (alternatePaths != null) {
- AlternateHandle[] alt;
-
- alt = new AlternateHandle[alternatePaths.length];
- for (int i = 0; i < alternatePaths.length; i++)
- alt[i] = openAlternate(alternatePaths[i]);
- alternates.set(alt);
- }
- }
-
- /** {@inheritDoc} */
- @Override
- public final File getDirectory() {
- return loose.getDirectory();
- }
-
- /**
- * <p>Getter for the field <code>packDirectory</code>.</p>
- *
- * @return the location of the <code>pack</code> directory.
- */
- public final File getPackDirectory() {
- return packed.getDirectory();
- }
-
- /**
- * <p>Getter for the field <code>preservedDirectory</code>.</p>
- *
- * @return the location of the <code>preserved</code> directory.
- */
- public final File getPreservedDirectory() {
- return preservedDirectory;
- }
-
- /** {@inheritDoc} */
- @Override
- public boolean exists() {
- return fs.exists(objects);
- }
-
- /** {@inheritDoc} */
- @Override
- public void create() throws IOException {
- loose.create();
- FileUtils.mkdir(infoDirectory);
- packed.create();
- }
-
- /** {@inheritDoc} */
- @Override
- public ObjectDirectoryInserter newInserter() {
- return new ObjectDirectoryInserter(this, config);
- }
-
- /**
- * Create a new inserter that inserts all objects as pack files, not loose
- * objects.
- *
- * @return new inserter.
- */
- public PackInserter newPackInserter() {
- return new PackInserter(this);
- }
-
- /** {@inheritDoc} */
- @Override
- public void close() {
- loose.close();
-
- packed.close();
-
- // Fully close all loaded alternates and clear the alternate list.
- AlternateHandle[] alt = alternates.get();
- if (alt != null && alternates.compareAndSet(alt, null)) {
- for(AlternateHandle od : alt)
- od.close();
- }
- }
-
- /** {@inheritDoc} */
- @Override
- public Collection<Pack> getPacks() {
- return packed.getPacks();
- }
-
- /**
- * {@inheritDoc}
- * <p>
- * Add a single existing pack to the list of available pack files.
- */
- @Override
- public Pack openPack(File pack)
- throws IOException {
- final String p = pack.getName();
- if (p.length() != 50 || !p.startsWith("pack-") || !p.endsWith(".pack")) //$NON-NLS-1$ //$NON-NLS-2$
- throw new IOException(MessageFormat.format(JGitText.get().notAValidPack, pack));
-
- // The pack and index are assumed to exist. The existence of other
- // extensions needs to be explicitly checked.
- //
- int extensions = PACK.getBit() | INDEX.getBit();
- final String base = p.substring(0, p.length() - 4);
- for (PackExt ext : PackExt.values()) {
- if ((extensions & ext.getBit()) == 0) {
- final String name = base + ext.getExtension();
- if (new File(pack.getParentFile(), name).exists())
- extensions |= ext.getBit();
- }
- }
-
- Pack res = new Pack(pack, extensions);
- packed.insert(res);
- return res;
- }
-
- /** {@inheritDoc} */
- @Override
- public String toString() {
- return "ObjectDirectory[" + getDirectory() + "]"; //$NON-NLS-1$ //$NON-NLS-2$
- }
-
- /** {@inheritDoc} */
- @Override
- public boolean has(AnyObjectId objectId) {
- return loose.hasCached(objectId)
- || hasPackedInSelfOrAlternate(objectId, null)
- || hasLooseInSelfOrAlternate(objectId, null);
- }
-
- private boolean hasPackedInSelfOrAlternate(AnyObjectId objectId,
- Set<AlternateHandle.Id> skips) {
- if (hasPackedObject(objectId)) {
- return true;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- if (alt.db.hasPackedInSelfOrAlternate(objectId, skips)) {
- return true;
- }
- }
- }
- return false;
- }
-
- private boolean hasLooseInSelfOrAlternate(AnyObjectId objectId,
- Set<AlternateHandle.Id> skips) {
- if (loose.has(objectId)) {
- return true;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- if (alt.db.hasLooseInSelfOrAlternate(objectId, skips)) {
- return true;
- }
- }
- }
- return false;
- }
-
- boolean hasPackedObject(AnyObjectId objectId) {
- return packed.has(objectId);
- }
-
- @Override
- void resolve(Set<ObjectId> matches, AbbreviatedObjectId id)
- throws IOException {
- resolve(matches, id, null);
- }
-
- private void resolve(Set<ObjectId> matches, AbbreviatedObjectId id,
- Set<AlternateHandle.Id> skips)
- throws IOException {
- if (!packed.resolve(matches, id, RESOLVE_ABBREV_LIMIT))
- return;
-
- if (!loose.resolve(matches, id, RESOLVE_ABBREV_LIMIT))
- return;
-
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- alt.db.resolve(matches, id, skips);
- if (matches.size() > RESOLVE_ABBREV_LIMIT) {
- return;
- }
- }
- }
- }
-
- @Override
- ObjectLoader openObject(WindowCursor curs, AnyObjectId objectId)
- throws IOException {
- if (loose.hasCached(objectId)) {
- ObjectLoader ldr = openLooseObject(curs, objectId);
- if (ldr != null) {
- return ldr;
- }
- }
- ObjectLoader ldr = openPackedFromSelfOrAlternate(curs, objectId, null);
- if (ldr != null) {
- return ldr;
- }
- return openLooseFromSelfOrAlternate(curs, objectId, null);
- }
-
- private ObjectLoader openPackedFromSelfOrAlternate(WindowCursor curs,
- AnyObjectId objectId, Set<AlternateHandle.Id> skips) {
- ObjectLoader ldr = openPackedObject(curs, objectId);
- if (ldr != null) {
- return ldr;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- ldr = alt.db.openPackedFromSelfOrAlternate(curs, objectId, skips);
- if (ldr != null) {
- return ldr;
- }
- }
- }
- return null;
- }
-
- private ObjectLoader openLooseFromSelfOrAlternate(WindowCursor curs,
- AnyObjectId objectId, Set<AlternateHandle.Id> skips)
- throws IOException {
- ObjectLoader ldr = openLooseObject(curs, objectId);
- if (ldr != null) {
- return ldr;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- ldr = alt.db.openLooseFromSelfOrAlternate(curs, objectId, skips);
- if (ldr != null) {
- return ldr;
- }
- }
- }
- return null;
- }
-
- ObjectLoader openPackedObject(WindowCursor curs, AnyObjectId objectId) {
- return packed.open(curs, objectId);
- }
-
- @Override
- ObjectLoader openLooseObject(WindowCursor curs, AnyObjectId id)
- throws IOException {
- return loose.open(curs, id);
- }
-
- @Override
- long getObjectSize(WindowCursor curs, AnyObjectId id)
- throws IOException {
- if (loose.hasCached(id)) {
- long len = loose.getSize(curs, id);
- if (0 <= len) {
- return len;
- }
- }
- long len = getPackedSizeFromSelfOrAlternate(curs, id, null);
- if (0 <= len) {
- return len;
- }
- return getLooseSizeFromSelfOrAlternate(curs, id, null);
- }
-
- private long getPackedSizeFromSelfOrAlternate(WindowCursor curs,
- AnyObjectId id, Set<AlternateHandle.Id> skips) {
- long len = packed.getSize(curs, id);
- if (0 <= len) {
- return len;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- len = alt.db.getPackedSizeFromSelfOrAlternate(curs, id, skips);
- if (0 <= len) {
- return len;
- }
- }
- }
- return -1;
- }
-
- private long getLooseSizeFromSelfOrAlternate(WindowCursor curs,
- AnyObjectId id, Set<AlternateHandle.Id> skips) throws IOException {
- long len = loose.getSize(curs, id);
- if (0 <= len) {
- return len;
- }
- skips = addMe(skips);
- for (AlternateHandle alt : myAlternates()) {
- if (!skips.contains(alt.getId())) {
- len = alt.db.getLooseSizeFromSelfOrAlternate(curs, id, skips);
- if (0 <= len) {
- return len;
- }
- }
- }
- return -1;
- }
-
- @Override
- void selectObjectRepresentation(PackWriter packer, ObjectToPack otp,
- WindowCursor curs) throws IOException {
- selectObjectRepresentation(packer, otp, curs, null);
- }
-
- private void selectObjectRepresentation(PackWriter packer, ObjectToPack otp,
- WindowCursor curs, Set<AlternateHandle.Id> skips) throws IOException {
- packed.selectRepresentation(packer, otp, curs);
-
- skips = addMe(skips);
- for (AlternateHandle h : myAlternates()) {
- if (!skips.contains(h.getId())) {
- h.db.selectObjectRepresentation(packer, otp, curs, skips);
- }
- }
- }
-
- @Override
- InsertLooseObjectResult insertUnpackedObject(File tmp, ObjectId id,
- boolean createDuplicate) throws IOException {
- // If the object is already in the repository, remove temporary file.
- //
- if (loose.hasCached(id)) {
- FileUtils.delete(tmp, FileUtils.RETRY);
- return InsertLooseObjectResult.EXISTS_LOOSE;
- }
- if (!createDuplicate && has(id)) {
- FileUtils.delete(tmp, FileUtils.RETRY);
- return InsertLooseObjectResult.EXISTS_PACKED;
- }
- return loose.insert(tmp, id);
- }
-
- @Override
- Config getConfig() {
- return config;
- }
-
- @Override
- FS getFS() {
- return fs;
- }
-
- @Override
- Set<ObjectId> getShallowCommits() throws IOException {
- if (shallowFile == null || !shallowFile.isFile())
- return Collections.emptySet();
-
- if (shallowFileSnapshot == null
- || shallowFileSnapshot.isModified(shallowFile)) {
- shallowCommitsIds = new HashSet<>();
-
- try (BufferedReader reader = open(shallowFile)) {
- String line;
- while ((line = reader.readLine()) != null) {
- try {
- shallowCommitsIds.add(ObjectId.fromString(line));
- } catch (IllegalArgumentException ex) {
- throw new IOException(MessageFormat
- .format(JGitText.get().badShallowLine, line),
- ex);
- }
- }
- }
-
- shallowFileSnapshot = FileSnapshot.save(shallowFile);
- }
-
- return shallowCommitsIds;
- }
-
- void closeAllPackHandles(File packFile) {
- // if the packfile already exists (because we are rewriting a
- // packfile for the same set of objects maybe with different
- // PackConfig) then make sure we get rid of all handles on the file.
- // Windows will not allow for rename otherwise.
- if (packFile.exists()) {
- for (Pack p : packed.getPacks()) {
- if (packFile.getPath().equals(p.getPackFile().getPath())) {
- p.close();
- break;
- }
- }
- }
- }
-
- AlternateHandle[] myAlternates() {
- AlternateHandle[] alt = alternates.get();
- if (alt == null) {
- synchronized (alternates) {
- alt = alternates.get();
- if (alt == null) {
- try {
- alt = loadAlternates();
- } catch (IOException e) {
- alt = new AlternateHandle[0];
- }
- alternates.set(alt);
- }
- }
- }
- return alt;
- }
-
- Set<AlternateHandle.Id> addMe(Set<AlternateHandle.Id> skips) {
- if (skips == null) {
- skips = new HashSet<>();
- }
- skips.add(handle.getId());
- return skips;
- }
-
- private AlternateHandle[] loadAlternates() throws IOException {
- final List<AlternateHandle> l = new ArrayList<>(4);
- try (BufferedReader br = open(alternatesFile)) {
- String line;
- while ((line = br.readLine()) != null) {
- l.add(openAlternate(line));
- }
- }
- return l.toArray(new AlternateHandle[0]);
- }
-
- private static BufferedReader open(File f)
- throws IOException, FileNotFoundException {
- return Files.newBufferedReader(f.toPath(), UTF_8);
- }
-
- private AlternateHandle openAlternate(String location)
- throws IOException {
- final File objdir = fs.resolve(objects, location);
- return openAlternate(objdir);
- }
-
- private AlternateHandle openAlternate(File objdir) throws IOException {
- final File parent = objdir.getParentFile();
- if (FileKey.isGitRepository(parent, fs)) {
- FileKey key = FileKey.exact(parent, fs);
- FileRepository db = (FileRepository) RepositoryCache.open(key);
- return new AlternateRepository(db);
- }
-
- ObjectDirectory db = new ObjectDirectory(config, objdir, null, fs, null);
- return new AlternateHandle(db);
- }
-
- /**
- * Compute the location of a loose object file.
- */
- @Override
- public File fileFor(AnyObjectId objectId) {
- return loose.fileFor(objectId);
- }
-
- static class AlternateHandle {
- static class Id {
- String alternateId;
-
- public Id(File object) {
- try {
- this.alternateId = object.getCanonicalPath();
- } catch (Exception e) {
- alternateId = null;
- }
- }
-
- @Override
- public boolean equals(Object o) {
- if (o == this) {
- return true;
- }
- if (o == null || !(o instanceof Id)) {
- return false;
- }
- Id aId = (Id) o;
- return Objects.equals(alternateId, aId.alternateId);
- }
-
- @Override
- public int hashCode() {
- if (alternateId == null) {
- return 1;
- }
- return alternateId.hashCode();
- }
- }
-
- final ObjectDirectory db;
-
- AlternateHandle(ObjectDirectory db) {
- this.db = db;
- }
-
- void close() {
- db.close();
- }
-
- public Id getId(){
- return db.getAlternateId();
- }
- }
-
- static class AlternateRepository extends AlternateHandle {
- final FileRepository repository;
-
- AlternateRepository(FileRepository r) {
- super(r.getObjectDatabase());
- repository = r;
- }
-
- @Override
- void close() {
- repository.close();
- }
- }
-
- /** {@inheritDoc} */
- @Override
- public ObjectDatabase newCachedDatabase() {
- return newCachedFileObjectDatabase();
- }
-
- CachedObjectDirectory newCachedFileObjectDatabase() {
- return new CachedObjectDirectory(this);
- }
-
- AlternateHandle.Id getAlternateId() {
- return new AlternateHandle.Id(objects);
- }
- }
|