Is there a better way of writing this code to avoid redundancy? - perl

Question

I have a segment of code in a program, which accepts GNU style input from a pipe (which is a list of file names). If STDIN does not contain data, I need to accept input from a predetermined text file containing file names.
I find myself needing to write redundant code. Is it possible to simplify this bit of code to avoid redundancy?
sub downloadlinkgen {
my $fh;
print "Printing links\n";
if ($getfilelist==1) {
open $fh, '<', "fuzzyfile" or die $!;
while (<$fh>) {
chomp ($_);
(my $fname,my $path, my $suffix) = fileparse($_);
my ($name, $ext) = $fname =~ /(.*)\.(.*)/;
my $newfile=$path.$name.".$ext";
$newfile =~ s/\s/%20/g;
$newfile =~ s/\/root/http:\/\/myip/;
print $newfile."\n";
}
} else {
while (<>) {
chomp ($_);
(my $fname,my $path, my $suffix) = fileparse($_);
my ($name, $ext) = $fname =~ /(.*)\.(.*)/;
my $newfile=$path.$name.".$ext";
$newfile =~ s/\s/%20/g;
$newfile =~ s/\/root/http:\/\/myip/;
print $newfile."\n";
}
}
}

Answer 1

Yes, just make the default ARGV filehandle open the file:
sub downloadlinkgen {
#ARGV = 'fuzzyfile' if $getfilelist == 1;
print "Printing links\n";
while (<>) {
chomp ($_);
(my $fname,my $path, my $suffix) = fileparse($_);
my ($name, $ext) = $fname =~ /(.*)\.(.*)/;
my $newfile=$path.$name.".$ext";
$newfile =~ s/\s/%20/g;
$newfile =~ s/\/root/http:\/\/myip/;
print $newfile."\n";
}
}

Answer 2

sub downloadlinkgen {
# default file handle
my $fh = \*ARGV;
print "Printing links\n";
if ($getfilelist==1) {
open $fh, '<', "fuzzyfile" or die $!;
}
while (<$fh>) {
chomp ($_);
(my $fname,my $path, my $suffix) = fileparse($_);
my ($name, $ext) = $fname =~ /(.*)\.(.*)/;
my $newfile=$path.$name.".$ext";
$newfile =~ s/\s/%20/g;
$newfile =~ s/\/root/http:\/\/myip/;
print $newfile."\n";
}
}
From perldoc -f readline
Reads from the filehandle whose typeglob is contained in EXPR (or from *ARGV if EXPR is not provided)
so \*ARGV is reference to file handle used when reading from <>, and you can use $fh in both cases.

Answer 3

Even if you don't know about ARGV, you could do something simple like this:
sub downloadlinkgen {
my $fh;
print "Printing links\n";
if ($getfilelist==1) {
open $fh, '<', "fuzzyfile" or die $!;
while (<$fh>) {
process_line($_);
}
} else {
while (<>) {
process_line($_);
}
}
}
sub process_line {
my $line = shift;
chomp ($line);
(my $fname,my $path, my $suffix) = fileparse($line);
my ($name, $ext) = $fname =~ /(.*)\.(.*)/;
my $newfile=$path.$name.".$ext";
$newfile =~ s/\s/%20/g;
$newfile =~ s/\/root/http:\/\/myip/;
print $newfile."\n";
}