Unverified Commit 37e42d01 authored by Naïm Favier's avatar Naïm Favier
Browse files

nixos/etc: skip resolv.conf in nixos-enter chroot 

nixos-enter sets up /etc/resolv.conf as a bind mount from the host
system, so trying to activate a system that sets
`environment.etc."resolv.conf"` (e.g. with systemd-resolved enabled)
results in an unhelpful warning.

Skip linking /etc/resolv.conf if we're in a nixos-enter environment, as
determined by the IN_NIXOS_ENTER environment variable.

Make the warnings more helpful, indicating which file we failed to link.

Unlink temporary files in case of failure.
parent 5a9a3353

nixos/modules/system/etc/setup-etc.pl

+18 −5
Original line number Diff line number Diff line
@@ -13,8 +13,12 @@ sub atomicSymlink { 
    my $tmp = "$target.tmp";

    unlink $tmp;

    symlink $source, $tmp or return 0;

    rename $tmp, $target or return 0;

    if (rename $tmp, $target) {

        return 1;

    } else {

        unlink $tmp;

        return 0;

    }

}
@@ -87,6 +91,12 @@ my @copied; 


sub link {

    my $fn = substr $File::Find::name, length($etc) + 1 or next;



    # nixos-enter sets up /etc/resolv.conf as a bind mount, so skip it.

    if ($fn eq "resolv.conf" and $ENV{'IN_NIXOS_ENTER'}) {

        return;

    }



    my $target = "/etc/$fn";

    File::Path::make_path(dirname $target);

    $created{$fn} = 1;
@@ -103,7 +113,7 @@ sub link { 
    if (-e "$_.mode") {

        my $mode = read_file("$_.mode"); chomp $mode;

        if ($mode eq "direct-symlink") {

            atomicSymlink readlink("$static/$fn"), $target or warn;

            atomicSymlink readlink("$static/$fn"), $target or warn "could not create symlink $target";

        } else {

            my $uid = read_file("$_.uid"); chomp $uid;

            my $gid = read_file("$_.gid"); chomp $gid;
@@ -112,12 +122,15 @@ sub link { 
            $gid = getgrnam $gid unless $gid =~ /^\+/;

            chown int($uid), int($gid), "$target.tmp" or warn;

            chmod oct($mode), "$target.tmp" or warn;

            rename "$target.tmp", $target or warn;

            unless (rename "$target.tmp", $target) {

                warn "could not create target $target";

                unlink "$target.tmp";

            }

        }

        push @copied, $fn;

        print CLEAN "$fn\n";

    } elsif (-l "$_") {

        atomicSymlink "$static/$fn", $target or warn;

        atomicSymlink "$static/$fn", $target or warn "could not create symlink $target";

    }

}