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/* Copyright (c) 2001-2021, The HSQL Development Group
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*
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*
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* list of conditions and the following disclaimer.
*
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*
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*
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package org.hsqldb.lib.tar;
/**
* Purely static structure defining our interface to the Tar Entry Header.
*
* The fields controlled here are fields for the individual tar file entries
* in an archive. There is no such thing as a Header Field at the top archive
* level.
*
* We use header field names as they are specified in the FreeBSD man page for
* tar in section 5 (Solaris and Linux have no such page in section 5).
* Where we use a constant, the constant name is just the FreeBSD field name
* capitalized.
* Since a single field is known as either "linkflag" or "typeflag", we are
* going with the UStar name typeflag for this field.
*
* We purposefully define no variable for this list of fields, since
* we DO NOT WANT TO access or change these values, due to application
* goals or JVM limitations:
* - gid
*
- uid
*
- linkname
*
- magic (UStar ID),
*
- magic version
*
- group name
*
- device major num
*
- device minor num
*
* Our application has no use for these, or Java has no ability to
* work with them.
*
* This class will be very elegant when refactored as an enum with enumMap(s)
* and using generics with auto-boxing instead of the ugly and non-validating
* casts.
*
* @author Blaine Simpson (blaine dot simpson at admc dot com)
*/
@SuppressWarnings("boxing")
public enum TarHeaderField {
// 1 PAST last position (in normal Java substring fashion).
/* Note that (with one exception), there is always 1 byte
* between a numeric field stop and the next start. This is
* because null byte must occupy the intervening position.
* This is not true for non-numeric fields (which includes the
* link-indicator/type-flag field, which is used as a code,
* and is not necessarily numeric with UStar format).
*
* As a consequence, there may be NO DELIMITER after
* non-numerics, which may occupy the entire field segment.
*
* Arg. man page for "pax" says that both original and ustar
* headers must be <= 100 chars. INCLUDING the trailing \0
* character. ??? GNU tar certainly does not honor this.
*/
name(0, 100),
mode(100, 107),
uid(108, 115),
gid(116, 123),
size(124, 135),
mtime(136, 147), // (File.lastModified()|*.getTime())/1000
checksum(148, 156),// "Queer terminator" in original code. ???
// Pax UStore does not follow spec and delimits this
// field like any other numeric, skipping the space byte.
typeflag(156, 157), // 1-byte CODE
// With current version, we are never doing anything with this
// field. In future, we will support x and/or g type here.
// N.b. Gnu Tar does not honor this Stop.
// The remaining are from UStar format:
magic(257, 263),
uname(265, 296),
gname(297, 328),
prefix(345, 399),
;
TarHeaderField(int start, int stop) {
this.start = start;
this.stop = stop;
}
private int start, stop;
// The getters below throw RuntimExceptions instead of
// TarMalformatExceptions because these errors indicate a dev problem,
// not some problem with a Header, or generating or reading a Header.
public int getStart() { return start; }
public int getStop() { return stop; }
}