org.apache.commons.compress.archivers.dump
Class DumpArchiveEntry

java.lang.Object
  org.apache.commons.compress.archivers.dump.DumpArchiveEntry

All Implemented Interfaces:

ArchiveEntry

public class DumpArchiveEntry
extends Object
implements ArchiveEntry

This class represents an entry in a Dump archive. It consists of the entry's header, the entry's File and any extended attributes.

DumpEntries that are created from the header bytes read from an archive are instantiated with the DumpArchiveEntry( byte[] ) constructor. These entries will be used when extracting from or listing the contents of an archive. These entries have their header filled in using the header bytes. They also set the File to null, since they reference an archive entry not a file.

DumpEntries can also be constructed from nothing but a name. This allows the programmer to construct the entry by hand, for instance when only an InputStream is available for writing to the archive, and the header information is constructed from other information. In this case the header fields are set to defaults and the File is set to null.

The C structure for a Dump Entry's header is:

 #define TP_BSIZE    1024          // size of each file block
 #define NTREC       10            // number of blocks to write at once
 #define HIGHDENSITYTREC 32        // number of blocks to write on high-density tapes
 #define TP_NINDIR   (TP_BSIZE/2)  // number if indirect inodes in record
 #define TP_NINOS    (TP_NINDIR / sizeof (int32_t))
 #define LBLSIZE     16
 #define NAMELEN     64

 #define OFS_MAGIC     (int)60011  // old format magic value
 #define NFS_MAGIC     (int)60012  // new format magic value
 #define FS_UFS2_MAGIC (int)0x19540119
 #define CHECKSUM      (int)84446  // constant used in checksum algorithm

 struct  s_spcl {
   int32_t c_type;             // record type (see below)
   int32_t c_date;             // date of this dump
   int32_t c_ddate;            // date of previous dump
   int32_t c_volume;           // dump volume number
   u_int32_t c_tapea;          // logical block of this record
   dump_ino_t c_ino;           // number of inode
   int32_t c_magic;            // magic number (see above)
   int32_t c_checksum;         // record checksum
 #ifdef  __linux__
   struct  new_bsd_inode c_dinode;
 #else
 #ifdef sunos
   struct  new_bsd_inode c_dinode;
 #else
   struct  dinode  c_dinode;   // ownership and mode of inode
 #endif
 #endif
   int32_t c_count;            // number of valid c_addr entries
   union u_data c_data;        // see above
   char    c_label[LBLSIZE];   // dump label
   int32_t c_level;            // level of this dump
   char    c_filesys[NAMELEN]; // name of dumpped file system
   char    c_dev[NAMELEN];     // name of dumpped device
   char    c_host[NAMELEN];    // name of dumpped host
   int32_t c_flags;            // additional information (see below)
   int32_t c_firstrec;         // first record on volume
   int32_t c_ntrec;            // blocksize on volume
   int32_t c_extattributes;    // additional inode info (see below)
   int32_t c_spare[30];        // reserved for future uses
 } s_spcl;

 //
 // flag values
 //
 #define DR_NEWHEADER     0x0001  // new format tape header
 #define DR_NEWINODEFMT   0x0002  // new format inodes on tape
 #define DR_COMPRESSED    0x0080  // dump tape is compressed
 #define DR_METAONLY      0x0100  // only the metadata of the inode has been dumped
 #define DR_INODEINFO     0x0002  // [SIC] TS_END header contains c_inos information
 #define DR_EXTATTRIBUTES 0x8000

 //
 // extattributes inode info
 //
 #define EXT_REGULAR         0
 #define EXT_MACOSFNDRINFO   1
 #define EXT_MACOSRESFORK    2
 #define EXT_XATTR           3

 // used for EA on tape
 #define EXT2_GOOD_OLD_INODE_SIZE    128
 #define EXT2_XATTR_MAGIC        0xEA020000  // block EA
 #define EXT2_XATTR_MAGIC2       0xEA020001  // in inode EA
 

The fields in bold are the same for all blocks. (This permitted multiple dumps to be written to a single tape.)

The C structure for the inode (file) information is:

 struct bsdtimeval {           //  **** alpha-*-linux is deviant
   __u32   tv_sec;
   __u32   tv_usec;
 };

 #define NDADDR      12
 #define NIADDR       3

 //
 // This is the new (4.4) BSD inode structure
 // copied from the FreeBSD 2.0  include file
 //
 struct new_bsd_inode {
   __u16       di_mode;           // file type, standard Unix permissions
   __s16       di_nlink;          // number of hard links to file.
   union {
      __u16       oldids[2];
      __u32       inumber;
   }           di_u;
   u_quad_t    di_size;           // file size
   struct bsdtimeval   di_atime;  // time file was last accessed
   struct bsdtimeval   di_mtime;  // time file was last modified
   struct bsdtimeval   di_ctime;  // time file was created
   __u32       di_db[NDADDR];
   __u32       di_ib[NIADDR];
   __u32       di_flags;          //
   __s32       di_blocks;         // number of disk blocks
   __s32       di_gen;            // generation number
   __u32       di_uid;            // user id (see /etc/passwd)
   __u32       di_gid;            // group id (see /etc/group)
   __s32       di_spare[2];       // unused
 };
 

It is important to note that the header DOES NOT have the name of the file. It can't since hard links mean that you may have multiple filenames for a single physical file. You must read the contents of the directory entries to learn the mapping(s) from filename to inode.

The C structure that indicates if a specific block is a real block that contains data or is a sparse block that is not persisted to the disk is:

 #define TP_BSIZE    1024
 #define TP_NINDIR   (TP_BSIZE/2)

 union u_data {
   char    s_addrs[TP_NINDIR]; // 1 => data; 0 => hole in inode
   int32_t s_inos[TP_NINOS];   // table of first inode on each volume
 } u_data;
 

This class is not thread-safe

Nested Class Summary

static class	DumpArchiveEntry.PERMISSION
static class	DumpArchiveEntry.TYPE

Field Summary

Fields inherited from interface org.apache.commons.compress.archivers.ArchiveEntry

SIZE_UNKNOWN

Constructor Summary

	DumpArchiveEntry() Default constructor.
	DumpArchiveEntry(String name, String simpleName) Constructor taking only filename.
protected	DumpArchiveEntry(String name, String simpleName, int ino, DumpArchiveEntry.TYPE type) Constructor taking name, inode and type.

Method Summary

boolean	equals(Object o)
Date	getAccessTime() Returns the time the file was last accessed.
Date	getCreationTime() Get file creation time.
int	getGeneration() Return the generation of the file.
int	getGroupId() Return the group id
int	getHeaderCount() Return the number of records in this segment.
int	getHeaderHoles() Return the number of sparse records in this segment.
DumpArchiveConstants.SEGMENT_TYPE	getHeaderType() Return the type of the tape segment header.
int	getIno() Returns the ino of the entry.
Date	getLastModifiedDate() The last modified date of the entry.
int	getMode() Return the access permissions on the entry.
String	getName() Returns the name of the entry.
int	getNlink() Return the number of hard links to the entry.
long	getOffset() Return the offset within the archive
Set<DumpArchiveEntry.PERMISSION>	getPermissions() Returns the permissions on the entry.
String	getSimpleName() Returns the path of the entry.
long	getSize() Returns the size of the entry.
DumpArchiveEntry.TYPE	getType() Get the type of the entry.
int	getUserId() Return the user id.
int	getVolume() Return the tape volume where this file is located.
int	hashCode()
boolean	isBlkDev() Is this a block device?
boolean	isChrDev() Is this a character device?
boolean	isDeleted() Has this file been deleted?
boolean	isDirectory() Is this a directory?
boolean	isFifo() Is this a fifo/pipe?
boolean	isFile() Is this a regular file?
boolean	isSocket() Is this a network device?
boolean	isSparseRecord(int idx) Is this a sparse record?
void	setAccessTime(Date atime) Set the time the file was last accessed.
void	setCreationTime(Date ctime) Set the file creation time.
void	setDeleted(boolean isDeleted) Set whether this file has been deleted.
void	setGeneration(int generation) Set the generation of the file.
void	setGroupId(int gid) Set the group id.
void	setLastModifiedDate(Date mtime) Set the time the file was last modified.
void	setMode(int mode) Set the access permissions on the entry.
void	setName(String name) Sets the name of the entry.
void	setNlink(int nlink) Set the number of hard links.
void	setOffset(long offset) Set the offset within the archive.
protected void	setSimpleName(String simpleName) Sets the path of the entry.
void	setSize(long size) Set the size of the entry.
void	setType(DumpArchiveEntry.TYPE type) Set the type of the entry.
void	setUserId(int uid) Set the user id.
void	setVolume(int volume) Set the tape volume.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

DumpArchiveEntry

public DumpArchiveEntry()

Default constructor.

DumpArchiveEntry

public DumpArchiveEntry(String name,
                        String simpleName)

Constructor taking only filename.

Parameters:

name - pathname

simpleName - actual filename.

DumpArchiveEntry

protected DumpArchiveEntry(String name,
                           String simpleName,
                           int ino,
                           DumpArchiveEntry.TYPE type)

Constructor taking name, inode and type.

Parameters:

name -

simpleName -

ino -

type -

Method Detail

getSimpleName

public String getSimpleName()

Returns the path of the entry.

Returns:

the path of the entry.

setSimpleName

protected void setSimpleName(String simpleName)

Sets the path of the entry.

getIno

public int getIno()

Returns the ino of the entry.

getNlink

public int getNlink()

Return the number of hard links to the entry.

setNlink

public void setNlink(int nlink)

Set the number of hard links.

getCreationTime

public Date getCreationTime()

Get file creation time.

setCreationTime

public void setCreationTime(Date ctime)

Set the file creation time.

getGeneration

public int getGeneration()

Return the generation of the file.

setGeneration

public void setGeneration(int generation)

Set the generation of the file.

isDeleted

public boolean isDeleted()

Has this file been deleted? (On valid on incremental dumps.)

setDeleted

public void setDeleted(boolean isDeleted)

Set whether this file has been deleted.

getOffset

public long getOffset()

Return the offset within the archive

setOffset

public void setOffset(long offset)

Set the offset within the archive.

getVolume

public int getVolume()

Return the tape volume where this file is located.

setVolume

public void setVolume(int volume)

Set the tape volume.

getHeaderType

public DumpArchiveConstants.SEGMENT_TYPE getHeaderType()

Return the type of the tape segment header.

getHeaderCount

public int getHeaderCount()

Return the number of records in this segment.

getHeaderHoles

public int getHeaderHoles()

Return the number of sparse records in this segment.

isSparseRecord

public boolean isSparseRecord(int idx)

Is this a sparse record?

hashCode

public int hashCode()

Overrides:

hashCode in class Object

See Also:

Object.hashCode()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

See Also:

Object.equals(Object o)

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

getName

public String getName()

Returns the name of the entry.

Specified by:

getName in interface ArchiveEntry

Returns:

the name of the entry.

setName

public final void setName(String name)

Sets the name of the entry.

getLastModifiedDate

public Date getLastModifiedDate()

The last modified date of the entry.

Specified by:

getLastModifiedDate in interface ArchiveEntry

isDirectory

public boolean isDirectory()

Is this a directory?

Specified by:

isDirectory in interface ArchiveEntry

isFile

public boolean isFile()

Is this a regular file?

isSocket

public boolean isSocket()

Is this a network device?

isChrDev

public boolean isChrDev()

Is this a character device?

isBlkDev

public boolean isBlkDev()

Is this a block device?

isFifo

public boolean isFifo()

Is this a fifo/pipe?

getType

public DumpArchiveEntry.TYPE getType()

Get the type of the entry.

setType

public void setType(DumpArchiveEntry.TYPE type)

Set the type of the entry.

getMode

public int getMode()

Return the access permissions on the entry.

setMode

public void setMode(int mode)

Set the access permissions on the entry.

getPermissions

public Set<DumpArchiveEntry.PERMISSION> getPermissions()

Returns the permissions on the entry.

getSize

public long getSize()

Returns the size of the entry.

Specified by:

getSize in interface ArchiveEntry

setSize

public void setSize(long size)

Set the size of the entry.

setLastModifiedDate

public void setLastModifiedDate(Date mtime)

Set the time the file was last modified.

getAccessTime

public Date getAccessTime()

Returns the time the file was last accessed.

setAccessTime

public void setAccessTime(Date atime)

Set the time the file was last accessed.

getUserId

public int getUserId()

Return the user id.

setUserId

public void setUserId(int uid)

Set the user id.

getGroupId

public int getGroupId()

Return the group id

setGroupId

public void setGroupId(int gid)

Set the group id.