path: root/ikiwiki-mass-rebuild

#!/usr/bin/perl
use warnings;
use strict;

sub supplemental_groups {
    my $user=shift;

    my @list;
    while (my @fields=getgrent()) {
        if (grep { $_ eq $user } split(' ', $fields[3])) {
            push @list, $fields[2];
        }
    }

    return @list;
}

sub samelists {
    my %a=map { $_ => 1 } split(' ', shift());
    my %b=map { $_ => 1 } split(' ', shift());

    foreach my $i (keys %b) {
        if (! exists $a{$i}) {
            return 0;
        }
    }
    foreach my $i (keys %a) {
        if (! exists $b{$i}) {
            return 0;
        }
    }
    return 1;
}

sub processline {
    my $user=shift;
    my $setup=shift;
    
    if (! getpwnam("$user")) {
        print STDERR "warning: user $user does not exist\n";
        return
    }
    if (! -f "$setup") {
        print STDERR "warning: $setup does not exist, skipping\n";
        return;
    }
    print "Processing $setup as user $user ...\n";
    # su is not used because it passes arguments through the shell,
    # which is not safe for untrusted setup file names.
    defined(my $pid = fork) or die "Can’t fork: $!";
    if (! $pid) {
        my ($uuid, $ugid) = (getpwnam($user))[2, 3];
        my $grouplist=join(" ", $ugid, sort {$a <=> $b} $ugid, supplemental_groups($user));
        if (! samelists(($)=$grouplist), $grouplist)) {
            die "failed to set egid $grouplist (got back $))";
        }
        $(=$ugid;
        $<=$uuid;
        $>=$uuid;
        if ($< != $uuid || $> != $uuid || $( != $ugid) {
            die "failed to drop permissions to $user";
        }
        %ENV=(
            PATH => $ENV{PATH},
            HOME => (getpwnam($user))[7],
        );
        exec("ikiwiki", "-setup", $setup, @ARGV);
        die "failed to run ikiwiki: $!";
    }
    waitpid($pid,0);
    if ($?) {
        print STDERR "Processing $setup as user $user failed with code $?\n";
    }
}

sub processlist {
    my $file=shift;
    my $forceuser=shift;

    my $list;
    open ($list, "<$file") || die "$file: $!";
    while (<$list>) {
        chomp;
        s/^\s+//;
        s/\s+$//;
        next if /^#/ || ! length;

        if (/^([^\s]+)\s+([^\s]+)$/) {
            my $user=$1;
            my $setup=$2;
            if (defined $forceuser && $forceuser ne $user) {
                print STDERR "warning: in $file line $., attempt to set user to $user, but user forced to $forceuser. Skipping\n";
            }
            processline($user, $setup);
        }
        elsif (/^([^\s]+)$/) {
            my $user=$1;
            my $home=(getpwnam($user))[7];
            if (defined $home && -d $home) {
                my $dotfile="$home/.ikiwiki/wikilist";
                if (-e $dotfile) {
                    processlist($dotfile, $user);
                }
            }
        }
    }
    close $list;
}

my $wikilist="/etc/ikiwiki/wikilist";

if (-e $wikilist) {
    processlist($wikilist);
}