Class DumpArchiveInputStream

All Implemented Interfaces:
Closeable, AutoCloseable

public class DumpArchiveInputStream extends ArchiveInputStream<DumpArchiveEntry>
The DumpArchiveInputStream reads a UNIX dump archive as an InputStream. Methods are provided to position at each successive entry in the archive, and the read each entry as a normal input stream using read().

There doesn't seem to exist a hint on the encoding of string values in any piece documentation. Given the main purpose of dump/restore is backing up a system it seems very likely the format uses the current default encoding of the system.

Since:
1.3
  • Field Details

    • CURRENT_PATH_SEGMENT

      private static final String CURRENT_PATH_SEGMENT
      See Also:
    • PARENT_PATH_SEGMENT

      private static final String PARENT_PATH_SEGMENT
      See Also:
    • summary

      private final DumpArchiveSummary summary
    • active

      private DumpArchiveEntry active
    • isClosed

      private boolean isClosed
    • hasHitEOF

      private boolean hasHitEOF
    • entrySize

      private long entrySize
    • entryOffset

      private long entryOffset
    • readIdx

      private int readIdx
    • readBuf

      private final byte[] readBuf
    • blockBuffer

      private byte[] blockBuffer
    • recordOffset

      private int recordOffset
    • filepos

      private long filepos
    • raw

      protected TapeInputStream raw
    • names

      private final Map<Integer,Dirent> names
      Map of ino -> dirent entry. We can use this to reconstruct full paths.
    • pending

      private final Map<Integer,DumpArchiveEntry> pending
      Map of ino -> (directory) entry when we're missing one or more elements in the path.
    • queue

      private final Queue<DumpArchiveEntry> queue
      Queue of (directory) entries where we now have the full path.
    • zipEncoding

      private final ZipEncoding zipEncoding
      The encoding to use for file names and labels.
  • Constructor Details

    • DumpArchiveInputStream

      public DumpArchiveInputStream(InputStream is) throws ArchiveException
      Constructor using the platform's default encoding for file names.
      Parameters:
      is - stream to read from
      Throws:
      ArchiveException - on error
    • DumpArchiveInputStream

      public DumpArchiveInputStream(InputStream is, String encoding) throws ArchiveException
      Constructs a new instance.
      Parameters:
      is - stream to read from
      encoding - the encoding to use for file names, use null for the platform's default encoding
      Throws:
      ArchiveException - on error
      Since:
      1.6
  • Method Details

    • matches

      public static boolean matches(byte[] buffer, int length)
      Look at the first few bytes of the file to decide if it's a dump archive. With 32 bytes we can look at the magic value, with a full 1k we can verify the checksum.
      Parameters:
      buffer - data to match
      length - length of data
      Returns:
      whether the buffer seems to contain dump data
    • close

      public void close() throws IOException
      Closes the stream for this entry.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterInputStream
      Throws:
      IOException
    • getBytesRead

      public long getBytesRead()
      Description copied from class: ArchiveInputStream
      Gets the current number of bytes read from this stream.
      Overrides:
      getBytesRead in class ArchiveInputStream<DumpArchiveEntry>
      Returns:
      the number of read bytes
    • getCount

      @Deprecated public int getCount()
      Deprecated.
      Description copied from class: ArchiveInputStream
      Gets the current number of bytes read from this stream.
      Overrides:
      getCount in class ArchiveInputStream<DumpArchiveEntry>
      Returns:
      the number of read bytes
    • getNextDumpEntry

      @Deprecated public DumpArchiveEntry getNextDumpEntry() throws IOException
      Deprecated.
      Reads the next entry.
      Returns:
      the next entry
      Throws:
      IOException - on error
    • getNextEntry

      public DumpArchiveEntry getNextEntry() throws IOException
      Description copied from class: ArchiveInputStream
      Gets the next Archive Entry in this Stream.
      Specified by:
      getNextEntry in class ArchiveInputStream<DumpArchiveEntry>
      Returns:
      the next entry, or null if there are no more entries.
      Throws:
      IOException - if the next entry could not be read.
    • getPath

      private String getPath(DumpArchiveEntry entry) throws DumpArchiveException
      Gets full path for specified archive entry, or null if there's a gap.
      Parameters:
      entry -
      Returns:
      full path for specified archive entry, or null if there's a gap.
      Throws:
      DumpArchiveException - Infinite loop detected in directory entries.
    • getSummary

      public DumpArchiveSummary getSummary()
      Gets the archive summary information.
      Returns:
      the summary
    • read

      public int read(byte[] buf, int off, int len) throws IOException
      Reads bytes from the current dump archive entry. This method is aware of the boundaries of the current entry in the archive and will deal with them as if they were this stream's start and EOF.
      Overrides:
      read in class FilterInputStream
      Parameters:
      buf - The buffer into which to place bytes read.
      off - The offset at which to place bytes read.
      len - The number of bytes to read.
      Returns:
      The number of bytes read, or -1 at EOF.
      Throws:
      IOException - on error
    • readBITS

      private void readBITS() throws IOException
      Read BITS segment.
      Throws:
      IOException
    • readCLRI

      private void readCLRI() throws IOException
      Read CLRI (deleted inode) segment.
      Throws:
      IOException
    • readDirectoryEntry

      private void readDirectoryEntry(DumpArchiveEntry entry) throws IOException
      Read directory entry.
      Throws:
      IOException