Class ObjectDirectoryPackParser

    • Field Detail

      • crc

        private final java.util.zip.CRC32 crc
        CRC-32 computation for objects that are appended onto the pack.
      • tailDigest

        private final java.security.MessageDigest tailDigest
        Running SHA-1 of any base objects appended after origEnd.
      • indexVersion

        private int indexVersion
        Preferred format version of the pack-*.idx file to generate.
      • keepEmpty

        private boolean keepEmpty
        If true, pack with 0 objects will be stored. Usually these are deleted.
      • tmpPack

        private java.io.File tmpPack
        Path of the temporary file holding the pack data.
      • tmpIdx

        private java.io.File tmpIdx
        Path of the index created for the pack, to find objects quickly at read time.
      • out

        private java.io.RandomAccessFile out
        Read/write handle to tmpPack while it is being parsed.
      • origEnd

        private long origEnd
        Length of the original pack stream, before missing bases were appended.
      • origHash

        private byte[] origHash
        The original checksum of data up to origEnd.
      • packEnd

        private long packEnd
        Current end of the pack file.
      • packHash

        private byte[] packHash
        Checksum of the entire pack file.
      • def

        private java.util.zip.Deflater def
        Compresses delta bases when completing a thin pack.
      • newPack

        private PackFile newPack
        The pack that was created, if parsing was successful.
    • Constructor Detail

      • ObjectDirectoryPackParser

        ObjectDirectoryPackParser​(FileObjectDatabase odb,
                                  java.io.InputStream src)
    • Method Detail

      • setIndexVersion

        public void setIndexVersion​(int version)
        Set the pack index file format version this instance will create.
        Parameters:
        version - the version to write. The special version 0 designates the oldest (most compatible) format available for the objects.
        See Also:
        PackIndexWriter
      • setKeepEmpty

        public void setKeepEmpty​(boolean empty)
        Configure this index pack instance to keep an empty pack.

        By default an empty pack (a pack with no objects) is not kept, as doi so is completely pointless. With no objects in the pack there is no d stored by it, so the pack is unnecessary.

        Parameters:
        empty - true to enable keeping an empty pack.
      • getPackFile

        public PackFile getPackFile()
        Get the imported PackFile.

        This method is supplied only to support testing; applications shouldn't be using it directly to access the imported data.

        Returns:
        the imported PackFile, if parsing was successful.
      • getPackSize

        public long getPackSize()
        Get the size of the newly created pack.

        This will also include the pack index size if an index was created. This method should only be called after pack parsing is finished.

        Overrides:
        getPackSize in class PackParser
        Returns:
        the pack size (including the index size) or -1 if the size cannot be determined
      • parse

        public PackLock parse​(ProgressMonitor receiving,
                              ProgressMonitor resolving)
                       throws java.io.IOException
        Parse the pack stream.
        Overrides:
        parse in class PackParser
        Parameters:
        receiving - receives progress feedback during the initial receiving objects phase. If null, NullProgressMonitor will be used.
        resolving - receives progress feedback during the resolving objects phase.
        Returns:
        the pack lock, if one was requested by setting PackParser.setLockMessage(String).
        Throws:
        java.io.IOException - the stream is malformed, or contains corrupt objects.
      • onPackHeader

        protected void onPackHeader​(long objectCount)
                             throws java.io.IOException
        Provide the implementation with the original stream's pack header.
        Specified by:
        onPackHeader in class PackParser
        Parameters:
        objectCount - number of objects expected in the stream.
        Throws:
        java.io.IOException - the implementation refuses to work with this many objects.
      • onBeginWholeObject

        protected void onBeginWholeObject​(long streamPosition,
                                          int type,
                                          long inflatedSize)
                                   throws java.io.IOException
        Event notifying the start of an object stored whole (not as a delta).
        Specified by:
        onBeginWholeObject in class PackParser
        Parameters:
        streamPosition - position of this object in the incoming stream.
        type - type of the object; one of Constants.OBJ_COMMIT, Constants.OBJ_TREE, Constants.OBJ_BLOB, or Constants.OBJ_TAG.
        inflatedSize - size of the object when fully inflated. The size stored within the pack may be larger or smaller, and is not yet known.
        Throws:
        java.io.IOException - the object cannot be recorded.
      • onEndWholeObject

        protected void onEndWholeObject​(PackedObjectInfo info)
                                 throws java.io.IOException
        Event notifying the current object.
        Specified by:
        onEndWholeObject in class PackParser
        Parameters:
        info - object information.
        Throws:
        java.io.IOException - the object cannot be recorded.
      • onBeginOfsDelta

        protected void onBeginOfsDelta​(long streamPosition,
                                       long baseStreamPosition,
                                       long inflatedSize)
                                throws java.io.IOException
        Event notifying start of a delta referencing its base by offset.
        Specified by:
        onBeginOfsDelta in class PackParser
        Parameters:
        streamPosition - position of this object in the incoming stream.
        baseStreamPosition - position of the base object in the incoming stream. The base must be before the delta, therefore baseStreamPosition < deltaStreamPosition. This is not the position returned by a prior end object event.
        inflatedSize - size of the delta when fully inflated. The size stored within the pack may be larger or smaller, and is not yet known.
        Throws:
        java.io.IOException - the object cannot be recorded.
      • onBeginRefDelta

        protected void onBeginRefDelta​(long streamPosition,
                                       AnyObjectId baseId,
                                       long inflatedSize)
                                throws java.io.IOException
        Event notifying start of a delta referencing its base by ObjectId.
        Specified by:
        onBeginRefDelta in class PackParser
        Parameters:
        streamPosition - position of this object in the incoming stream.
        baseId - name of the base object. This object may be later in the stream, or might not appear at all in the stream (in the case of a thin-pack).
        inflatedSize - size of the delta when fully inflated. The size stored within the pack may be larger or smaller, and is not yet known.
        Throws:
        java.io.IOException - the object cannot be recorded.
      • onEndDelta

        protected PackParser.UnresolvedDelta onEndDelta()
                                                 throws java.io.IOException
        Event notifying the current object.
        Overrides:
        onEndDelta in class PackParser
        Returns:
        object information that must be populated with at least the offset.
        Throws:
        java.io.IOException - the object cannot be recorded.
      • onInflatedObjectData

        protected void onInflatedObjectData​(PackedObjectInfo obj,
                                            int typeCode,
                                            byte[] data)
                                     throws java.io.IOException
        Invoked for commits, trees, tags, and small blobs.
        Specified by:
        onInflatedObjectData in class PackParser
        Parameters:
        obj - the object info, populated.
        typeCode - the type of the object.
        data - inflated data for the object.
        Throws:
        java.io.IOException - the object cannot be archived.
      • onObjectHeader

        protected void onObjectHeader​(PackParser.Source src,
                                      byte[] raw,
                                      int pos,
                                      int len)
                               throws java.io.IOException
        Store (and/or checksum) an object header.

        Invoked after any of the onBegin() events. The entire header is supplied in a single invocation, before any object data is supplied.

        Specified by:
        onObjectHeader in class PackParser
        Parameters:
        src - where the data came from
        raw - buffer to read data from.
        pos - first offset within buffer that is valid.
        len - number of bytes in buffer that are valid.
        Throws:
        java.io.IOException - the stream cannot be archived.
      • onObjectData

        protected void onObjectData​(PackParser.Source src,
                                    byte[] raw,
                                    int pos,
                                    int len)
                             throws java.io.IOException
        Store (and/or checksum) a portion of an object's data.

        This method may be invoked multiple times per object, depending on the size of the object, the size of the parser's internal read buffer, and the alignment of the object relative to the read buffer.

        Invoked after PackParser.onObjectHeader(Source, byte[], int, int).

        Specified by:
        onObjectData in class PackParser
        Parameters:
        src - where the data came from
        raw - buffer to read data from.
        pos - first offset within buffer that is valid.
        len - number of bytes in buffer that are valid.
        Throws:
        java.io.IOException - the stream cannot be archived.
      • onStoreStream

        protected void onStoreStream​(byte[] raw,
                                     int pos,
                                     int len)
                              throws java.io.IOException
        Store bytes received from the raw stream.

        This method is invoked during PackParser.parse(ProgressMonitor) as data is consumed from the incoming stream. Implementors may use this event to archive the raw incoming stream to the destination repository in large chunks, without paying attention to object boundaries.

        The only component of the pack not supplied to this method is the last 20 bytes of the pack that comprise the trailing SHA-1 checksum. Those are passed to PackParser.onPackFooter(byte[]).

        Specified by:
        onStoreStream in class PackParser
        Parameters:
        raw - buffer to copy data out of.
        pos - first offset within the buffer that is valid.
        len - number of bytes in the buffer that are valid.
        Throws:
        java.io.IOException - the stream cannot be archived.
      • onPackFooter

        protected void onPackFooter​(byte[] hash)
                             throws java.io.IOException
        Provide the implementation with the original stream's pack footer.
        Specified by:
        onPackFooter in class PackParser
        Parameters:
        hash - the trailing 20 bytes of the pack, this is a SHA-1 checksum of all of the pack data.
        Throws:
        java.io.IOException - the stream cannot be archived.
      • seekDatabase

        protected PackParser.ObjectTypeAndSize seekDatabase​(PackParser.UnresolvedDelta delta,
                                                            PackParser.ObjectTypeAndSize info)
                                                     throws java.io.IOException
        Reposition the database to re-read a previously stored object.

        If the database is computing CRC-32 checksums for object data, it should reset its internal CRC instance during this method call.

        Specified by:
        seekDatabase in class PackParser
        Parameters:
        delta - the object position to begin reading from. This is an instance previously returned by PackParser.onEndDelta().
        info - object to populate with type and size.
        Returns:
        the info object.
        Throws:
        java.io.IOException - the database cannot reposition to this location.
      • readDatabase

        protected int readDatabase​(byte[] dst,
                                   int pos,
                                   int cnt)
                            throws java.io.IOException
        Read from the database's current position into the buffer.
        Specified by:
        readDatabase in class PackParser
        Parameters:
        dst - the buffer to copy read data into.
        pos - position within dst to start copying data into.
        cnt - ideal target number of bytes to read. Actual read length may be shorter.
        Returns:
        number of bytes stored.
        Throws:
        java.io.IOException - the database cannot be accessed.
      • checkCRC

        protected boolean checkCRC​(int oldCRC)
        Check the current CRC matches the expected value.

        This method is invoked when an object is read back in from the database and its data is used during delta resolution. The CRC is validated after the object has been fully read, allowing the parser to verify there was no silent data corruption.

        Implementations are free to ignore this check by always returning true if they are performing other data integrity validations at a lower level.

        Specified by:
        checkCRC in class PackParser
        Parameters:
        oldCRC - the prior CRC that was recorded during the first scan of the object from the pack stream.
        Returns:
        true if the CRC matches; false if it does not.
      • baseName

        private static java.lang.String baseName​(java.io.File tmpPack)
      • cleanupTemporaryFiles

        private void cleanupTemporaryFiles()
      • onAppendBase

        protected boolean onAppendBase​(int typeCode,
                                       byte[] data,
                                       PackedObjectInfo info)
                                throws java.io.IOException
        Provide the implementation with a base that was outside of the pack.

        This event only occurs on a thin pack for base objects that were outside of the pack and came from the local repository. Usually an implementation uses this event to compress the base and append it onto the end of the pack, so the pack stays self-contained.

        Specified by:
        onAppendBase in class PackParser
        Parameters:
        typeCode - type of the base object.
        data - complete content of the base object.
        info - packed object information for this base. Implementors must populate the CRC and offset members if returning true.
        Returns:
        true if the info should be included in the object list returned by PackParser.getSortedObjectList(Comparator), false if it should not be included.
        Throws:
        java.io.IOException - the base could not be included into the pack.
      • onEndThinPack

        protected void onEndThinPack()
                              throws java.io.IOException
        Event indicating a thin pack has been completely processed.

        This event is invoked only if a thin pack has delta references to objects external from the pack. The event is called after all of those deltas have been resolved.

        Specified by:
        onEndThinPack in class PackParser
        Throws:
        java.io.IOException - the pack cannot be archived.
      • writeIdx

        private void writeIdx()
                       throws java.io.IOException
        Throws:
        java.io.IOException
      • renameAndOpenPack

        private PackLock renameAndOpenPack​(java.lang.String lockMessage)
                                    throws java.io.IOException
        Throws:
        java.io.IOException