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package File::Read;
use strict;
use Carp;
use File::Slurp ();
require Exporter;
{ no strict;
$VERSION = '0.0801';
@ISA = qw(Exporter);
@EXPORT = qw(read_file read_files);
}
*read_files = \&read_file;
=head1 NAME
File::Read - Unique interface for reading one or more files
=head1 VERSION
Version 0.0801
=head1 SYNOPSIS
use File::Read;
# read a file
$file = read_file($path);
# read several files
@files = read_files(@paths);
# aggregate several files
$file = read_files(@paths);
# read a file as root, skip comments and blank lines
$file = read_file({ as_root => 1, skip_comments => 1, skip_blanks => 1 }, $path);
=head1 DESCRIPTION
This module mainly proposes functions for reading one or more files,
with different options. See below for more details and examples.
=head2 Rationale
This module was created to address a quite specific need: reading many
files, some as a normal user and others as root, and eventually do a
little more processing, all while being at the same time compatible
with Perl 5.004. C<File::Slurp> addresses the first point, but not the
others, hence the creation of C<File::Read>. If you don't need reading
files as root or the post-processing features, then it's faster to
directly use C<File::Slurp>.
=head1 EXPORT
By default, this module exports all the functions documented afterhand.
It also recognizes import options. For example
use File::Read 'err_mode=quiet';
set C<read_file()>'s C<err_mode> option default value to C<"quiet">.
=head1 FUNCTIONS
=over
=item B<read_file()>
Read the files given in argument and return their content,
as as list, one element per file, when called in list context,
or as one big chunk of text when called in scalar context.
Options can be set using a hashref as first parameter.
B<Options>
=over
=item *
C<aggregate> controls how the function returns the content of the files
that were successfully read. By default, When set to true (default),
the function returns the content as a scalar; when set to false, the
content is returned as a list.
=item *
C<as_root> tells the function to read the given file(s) as root using
the command indicated by the C<cmd> option.
=item *
C<cmd> sets the shell command used for reading files as root. Default
is C<"sudo cat">. Therefore you need B<sudo(8)> and B<cat(1)> on your
system, and F<sudoers(5)> must be set so the user can execute B<cat(1)>.
=item *
C<err_mode> controls how the function behaves when an error occurs.
Available values are C<"croak">, C<"carp"> and C<"quiet">.
Default value is C<"croak">.
=item *
C<skip_comments> tells the functions to remove all comment lines from
the read files.
=item *
C<skip_blanks> tells the functions to remove all blank lines from
the read files.
=item *
C<to_ascii> tells the functions to convert the text to US-ASCII using
C<Text::Unidecode>. If this module is not available, non-ASCII data
are deleted.
=back
B<Examples>
Just read a file:
my $file = read_file($path);
Read a file, returning it as list:
my @file = read_file({ aggregate => 0 }, $path);
Read a file, skipping comments:
my $file = read_file({ skip_comments => 1 }, $path);
Read several files, skipping blank lines and comments:
my @files = read_file({ skip_comments => 1, skip_blanks => 1 }, @paths);
=item B<read_files()>
C<read_files()> is just an alias for C<read_file()> so that it look more
sane when reading several files.
=cut
my %defaults = (
aggregate => 1,
cmd => "sudo cat",
err_mode => 'croak',
skip_comments => 0,
skip_blanks => 0,
to_ascii => 0,
);
sub import {
my ($module, @args) = @_;
my @new = ();
# parse arguments
for my $arg (@args) {
if (index($arg, '=') >= 0) {
my ($opt, $val) = split '=', $arg;
$defaults{$opt} = $val if exists $defaults{$opt};
}
else {
push @new, $arg
}
}
$module->export_to_level(1, $module, @new);
}
sub read_file {
my %opts = ref $_[0] eq 'HASH' ? %{+shift} : ();
my @paths = @_;
my @files = ();
# check options
for my $opt (keys %defaults) {
$opts{$opt} = $defaults{$opt} unless defined $opts{$opt}
}
# define error handler
$opts{err_mode} =~ /^(?:carp|croak|quiet)$/
or croak "error: Bad value '$opts{err_mode}' for option 'err_mode'";
my %err_with = (
'carp' => \&carp,
'croak' => \&croak,
'quiet' => sub{},
);
my $err_sub = $err_with{$opts{err_mode}};
$err_sub->("error: This function needs at least one path") unless @paths;
for my $path (@paths) {
my @lines = ();
my $error = '';
# first, read the file
if ($opts{as_root}) { # ... as root
my $redir = $opts{err_mode} eq 'quiet' ? '2>&1' : '';
@lines = `$opts{cmd} $path $redir`;
if ($?) {
if (not -f $path) {
$! = eval { require Errno; Errno->import(":POSIX"); ENOENT() } || 2
}
elsif (not -r $path) {
$! = eval { require Errno; Errno->import(":POSIX"); EACCES() } || 13
}
else {
$! = 1024
}
($error = "$!") =~ s/ 1024//;
}
}
else { # ... as a normal user
@lines = eval { File::Slurp::read_file($path) };
$error = $@;
}
# if there's an error
$error and $err_sub->("error: $error");
# if there's any content at all...
if (@lines) {
# ... then do some filtering work if asked so
@lines = grep { ! /^$/ } @lines if $opts{skip_blanks};
@lines = grep { ! /^\s*#/ } @lines if $opts{skip_comments};
@lines = map { _to_ascii($_) } @lines if $opts{to_ascii};
}
push @files, $opts{aggregate} ? join('', @lines) : @lines;
}
# how to return the content(s)?
return wantarray ? @files : join '', @files
}
# Text::Unidecode doesn't work on Perl 5.6
my $has_unidecode = eval "require 5.008; require Text::Unidecode; 1"; $@ = "";
sub _to_ascii {
# use Text::Unidecode if available
if ($has_unidecode) {
return Text::Unidecode::unidecode(@_)
}
else { # use a simple s///
my @text = @_;
map { s/[^\x00-\x7f]//g } @text;
return @text
}
}
=back
=head1 DIAGNOSTICS
=over
=item C<Bad value '%s' for option '%s'>
B<(E)> You gave a bad value for the indicated option. Please check the
documentation for the valid values.
=item C<This function needs at least one path>
B<(E)> You called a function without giving it argument.
=back
=head1 SEE ALSO
L<File::Slurp>
L<IO::All>
=head1 AUTHOR
SE<eacute>bastien Aperghis-Tramoni, C<< <sebastien at aperghis.net> >>
=head1 BUGS
Please report any bugs or feature requests to
C<bug-file-read at rt.cpan.org>, or through the web interface at
I will be notified, and then you'll automatically be notified of progress on
your bug as I make changes.
=head1 SUPPORT
You can find documentation for this module with the perldoc command.
perldoc File::Read
You can also look for information at:
=over 4
=item *
AnnoCPAN: Annotated CPAN documentation -
=item *
CPAN Ratings -
=item *
RT: CPAN's request tracker -
=item *
Search CPAN -
=back
=head1 COPYRIGHT & LICENSE
Copyright (C) 2006, 2007 SE<eacute>bastien Aperghis-Tramoni, all rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=cut
1; # End of File::Read