test_chmod.pl

#!/usr/bin/env perl
use v5.10;
use strict;
use warnings;
use List::AllUtils qw/shuffle/;
use File::stat;

my $NUMBER = shift || 10;

my @ps_who = qw( augo ugo ago go auo uo ao o aug ug ag g au u a );

my @ps_perms = qw( rwx wx rx x rw w r );

my @set;
for my $w ( @ps_who ) {
    for my $p ( @ps_perms ) {
        push @set, "$w=$p";
    }
}

my @clr;
for my $w ( @ps_who ) {
    for my $p ( @ps_perms ) {
        push @clr, "$w-$p";
    }
}

my @add;
for my $w ( @ps_who ) {
    for my $p ( @ps_perms ) {
        push @add, "$w+$p";
    }
}

sub item {
    my $aref = shift;
    return $aref->[int(rand(scalar @$aref))];
}

sub strmode {
    my $file = shift;
    sprintf("%05o", stat($file)->mode & 07777);
}

my %combo;

my $aoa = [ \@set, \@clr, \@add ];

for (1 .. $NUMBER) {
    for my $n (1 .. 3) {
        my @test = map { item($aoa) } 1 .. $n;
        $combo{join(",", shuffle( map { item($_) } @test ))} = 1;
    }
}

my %seen;
my $dir = "test";
for my $c (sort keys %combo) {
    for my $mode ( 0777, 0 ) {
        chmod $mode, $dir;
        my $old = strmode($dir);
        system("/bin/chmod", $c, $dir);
        my $new = strmode($dir);
##        printf("%-30s: %s -> %s\n", $c, $old, $new);
        $seen{$c}{$new} ||= [$c, $old, $new];
    }
}

my @cases;
push @cases, $_ for map { values $_ } values %seen;

printf("%30s %s %s\n", @$_) for @cases;