NAME¶
Archive::Ar - Interface for manipulating ar archives
SYNOPSIS¶
use Archive::Ar;
my $ar = new Archive::Ar("./foo.ar");
$ar->add_data("newfile.txt","Some contents", $properties);
$ar->add_files("./bar.tar.gz", "bat.pl")
$ar->add_files(["./again.gz"]);
$ar->remove("file1", "file2");
$ar->remove(["file1", "file2");
my $filedata = $ar->get_content("bar.tar.gz");
my @files = $ar->list_files();
$ar->read("foo.deb");
$ar->write("outbound.ar");
$ar->DEBUG();
DESCRIPTION¶
Archive::Ar is a pure-perl way to handle standard ar archives.
This is useful if you have those types of old archives on the system, but it is
also useful because .deb packages for the Debian GNU/Linux distribution are ar
archives. This is one building block in a future chain of modules to build,
manipulate, extract, and test debian modules with no platform or architecture
dependence.
You may notice that the API to Archive::Ar is similar to Archive::Tar, and this
was done intentionally to keep similarity between the Archive::* modules
Class Methods¶
- •
- "new()"
- •
- "new($filename)"
- •
- "new(*GLOB,$debug)"
Returns a new Archive::Ar object. Without a filename or glob, it returns an
empty object. If passed a filename as a scalar or in a GLOB, it will
attempt to populate from either of those sources. If it fails, you will
receive undef, instead of an object reference.
This also can take a second optional debugging parameter. This acts exactly
as if "DEBUG()" is called on the object before it is returned.
If you have a "new()" that keeps failing, this should help.
- •
- "read($filename)"
- •
- "read(*GLOB)";
This reads a new file into the object, removing any ar archive already
represented in the object. Any calls to "DEBUG()" are not lost
by reading in a new file. Returns the number of bytes read, undef on
failure.
- •
- "read_memory($data)"
This read information from the first parameter, and attempts to parse and
treat it like an ar archive. Like "read()", it will wipe out
whatever you have in the object and replace it with the contents of the
new archive, even if it fails. Returns the number of bytes read
(processed) if successful, undef otherwise.
- •
- "list_files()"
This lists the files contained inside of the archive by filename, as an
array. If called in a scalar context, returns a reference to an
array.
- •
- "add_files("filename1",
"filename2")"
- •
- "add_files(["filename1",
"filename2"])"
Takes an array or an arrayref of filenames to add to the ar archive, in
order. The filenames can be paths to files, in which case the path
information is stripped off. Filenames longer than 16 characters are
truncated when written to disk in the format, so keep that in mind when
adding files.
Due to the nature of the ar archive format, "add_files()" will
store the uid, gid, mode, size, and creation date of the file as returned
by "stat()";
"add_files()" returns the number of files successfully added, or
undef on failure.
- •
- "add_data("filename",
$filedata)"
Takes an filename and a set of data to represent it. Unlike
"add_files", "add_data" is a virtual add, and does not
require data on disk to be present. The data is a hash that looks like:
$filedata = {
"data" => $data,
"uid" => $uid, #defaults to zero
"gid" => $gid, #defaults to zero
"date" => $date, #date in epoch seconds. Defaults to now.
"mode" => $mode, #defaults to 0100644;
}
You cannot add_data over another file however. This returns the file length
in bytes if it is successful, undef otherwise.
- •
- "write()"
- •
- "write("filename.ar")"
This method will return the data as an .ar archive, or will write to the
filename present if specified. If given a filename, "write()"
will return the length of the file written, in bytes, or undef on failure.
If the filename already exists, it will overwrite that file.
- •
- "get_content("filename")"
This returns a hash with the file content in it, including the data that the
file would naturally contain. If the file does not exist or no filename is
given, this returns undef. On success, a hash is returned with the
following keys:
name - The file name
date - The file date (in epoch seconds)
uid - The uid of the file
gid - The gid of the file
mode - The mode permissions
size - The size (in bytes) of the file
data - The contained data
- •
- "remove("filename1",
"filename2")"
- •
- "remove(["filename1",
"filename2"])"
The remove method takes a filenames as a list or as an arrayref, and removes
them, one at a time, from the Archive::Ar object. This returns the number
of files successfully removed from the archive.
- •
- "DEBUG()"
This method turns on debugging. Optionally this can be done by passing in a
value as the second parameter to new. While verbosity is enabled,
Archive::Ar will toss a "warn()" if there is a suspicious
condition or other problem while proceeding. This should help iron out any
problems you have while using the module.
CHANGES¶
- •
- Version 1.14 - October 14, 2009
Fix list_files to return a list in list context, to match doc.
Pad odd-size archives to an even number of bytes. Closes RT #18383 (thanks
to David Dick).
Fixed broken file perms (decimal mode stored as octal string). Closes RT
#49987 (thanks to Stephen Gran - debian bug #523515).
- •
- Version 1.13b - May 7th, 2003
Fixes to the Makefile.PL file. Ar.pm wasn't being put into /blib Style fix
to a line with non-standard unless parenthesis
- •
- Version 1.13 - April 30th, 2003
Removed unneeded exports. Thanks to pudge for the pointer.
- •
- Version 1.12 - April 14th, 2003
Found podchecker. CPAN HTML documentation should work right now.
- •
- Version 1.11 - April 10th, 2003
Trying to get the HTML POD documentation to come out correctly
- •
- Version 1.1 - April 10th, 2003
Documentation cleanups Added a "remove()" function
- •
- Version 1.0 - April 7th, 2003
This is the initial public release for CPAN, so everything is new.
TODO¶
A better unit test suite perhaps. I have a private one, but a public one would
be nice if there was good file faking module.
Fix / investigate stuff in the BUGS section.
BUGS¶
To be honest, I'm not sure of a couple of things. The first is that I know of ar
archives made on old AIX systems (pre 4.3?) that have a different header with
a different magic string, etc. This module perfectly (hopefully) handles ar
archives made with the modern ar command from the binutils distribution. If
anyone knows of anyway to produce these old-style AIX archives, or would like
to produce a few for testing, I would be much grateful.
There's no really good reason why this module
shouldn't run on Win32
platforms, but admittedly, this might change when we have a file exporting
function that supports owner and permission writing.
If you read in and write out a file, you get different md5sums, but it's still a
valid archive. I'm still investigating this, and consider it a minor bug.
COPYRIGHT¶
Archive::Ar is copyright 2003 Jay Bonci <jaybonci@cpan.org>. This program
is free software; you can redistribute it and/or modify it under the same
terms as Perl itself.