#!/bin/perl -w
    eval 'exec /usr/bin/perl -S $0 ${1+"$@"}'
        if 0; #$running_under_some_shell

use strict;
use File::Find ();

=head1 NAME

newest - find newest files in a directory tree

=head1 SYNOPSIS

   newest [-a] [-N] directory...

=head1 DESCRIPTION

Find the N newest files from the directories provided. Option -a also searches hidden directories. Very simple and short program.


=head1 NOTES

Only works on Unix.

=head1 SEE ALSO

L<File::Find>, L<find2perl>

=cut

# Set the variable $File::Find::dont_use_nlink if you're using AFS,
# since AFS cheats.

# for the convenience of &wanted calls, including -eval statements:
use vars qw/*name *dir *prune/;
*name   = *File::Find::name;
*dir    = *File::Find::dir;
*prune  = *File::Find::prune;

my @rwx = qw(--- --x -w- -wx r-- r-x rw- rwx);
my @moname = qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec);

my (%uid, %user);
while (my ($name, $pw, $uid) = getpwent) {
    $user{$uid} = $name unless exists $user{$uid};
}

my (%gid, %group);
while (my ($name, $pw, $gid) = getgrent) {
    $group{$gid} = $name unless exists $group{$gid};
}

# array of files
my @suite = ();       # files found
my @start= ();        # directories to start from
my $ssize = 0;        # max size of suite
my $all = 0;          # include .* patterns
my $errs = 0;         # arg errors
sub do_sort  {@suite = sort { $b->[1] <=> $a->[1]; } @suite;}

while ($_ = shift) {
	if ($ssize == 0 && /-[0-9]+$/) {	$ssize = -$_; }
	elsif (/-a/) { $all = 1; }
	elsif (-d) { push @start, $_; }
	else
	{	++$errs;
		print "$_ is not a directory\n"; }
}

die unless $errs == 0;

$ssize = 8 if $ssize <= 0;

# Traverse desired filesystems (follow_fast => 1,)?
File::Find::find(
	{wanted => \&wanted, no_chdir => 0},
	@start);
&do_sort if $ssize > @suite;
&report;
exit;
	
sub wanted
{
	if ($all == 0 && /^\..+/) { $File::Find::prune = 1; return; }

	my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
        $atime,$mtime,$ctime,$blksize,$blocks) = lstat($_);

	return if ! -f _ || $ssize <= @suite && $suite[$ssize-1]->[1] > $mtime;
	
	my @file = ($File::Find::name, $mtime);

	if ($ssize > @suite)
	{
		&do_sort if (push(@suite, \@file) >= $ssize);
		return;
	}

	my $i;
	for ($i = 0; $i < @suite; ++$i)
	{
		my $t = $suite[$i]->[1];
		if ($t < $mtime)
		{
			splice(@suite, $i, 0, \@file);
			pop(@suite);
			last;
		}
	}
}

sub report
{
	my ($dev,$ino,$mode,$nlink,$uid,$gid);
	my $name;
	foreach (@suite)
	{
		my $name = $_->[0];
		($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($name);
		&ls($name);
	}
}


sub sizemm {
    my $rdev = shift;
    sprintf("%3d, %3d", ($rdev >> 8) & 0xff, $rdev & 0xff);
}

sub ls {
    my ($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,
        $atime,$mtime,$ctime,$blksize,$blocks) = lstat(_);
    my $pname = shift;

    $blocks
        or $blocks = int(($size + 1023) / 1024);

    my $perms = $rwx[$mode & 7];
    $mode >>= 3;
    $perms = $rwx[$mode & 7] . $perms;
    $mode >>= 3;
    $perms = $rwx[$mode & 7] . $perms;
    substr($perms, 2, 1) =~ tr/-x/Ss/ if -u _;
    substr($perms, 5, 1) =~ tr/-x/Ss/ if -g _;
    substr($perms, 8, 1) =~ tr/-x/Tt/ if -k _;
    if    (-f _) { $perms = '-' . $perms; }
    elsif (-d _) { $perms = 'd' . $perms; }
    elsif (-l _) { $perms = 'l' . $perms; $pname .= ' -> ' . readlink($_); }
    elsif (-c _) { $perms = 'c' . $perms; $size = sizemm($rdev); }
    elsif (-b _) { $perms = 'b' . $perms; $size = sizemm($rdev); }
    elsif (-p _) { $perms = 'p' . $perms; }
    elsif (-S _) { $perms = 's' . $perms; }
    else         { $perms = '?' . $perms; }

    my $user = $user{$uid} || $uid;
    my $group = $group{$gid} || $gid;

    my ($sec,$min,$hour,$mday,$mon,$timeyear) = localtime($mtime);
    printf "%-10s %3d %-8s %-8s %8.2fk  %5s %s %2d %02d:%02d:%02d %s\n",
            $perms,
                  $nlink,
                      $user,
                           $group,
                                $size/1024,
                                        $timeyear + 1900,
                                            $moname[$mon],
                                               $mday,
                                                  $hour, $min, $sec,
                                                         $pname;
#    if (-M _ > 365.25 / 2) {
#        $timeyear += 1900;
#    } else {
#        $timeyear = sprintf("%02d:%02d", $hour, $min);
#    }
#
#    printf "%5lu %4ld %-10s %3d %-8s %-8s %8s %s %2d %5s %s\n",
#            $ino,
#                 $blocks,
#                      $perms,
#                            $nlink,
#                                $user,
#                                     $group,
#                                          $size,
#                                              $moname[$mon],
#                                                 $mday,
#                                                     $timeyear,
#                                                         $pname;
    1;
}