301 lines
11 KiB
Perl
301 lines
11 KiB
Perl
#! @perl@
|
||
|
||
use strict;
|
||
use warnings;
|
||
use File::Basename;
|
||
use File::Slurp;
|
||
use Cwd 'abs_path';
|
||
|
||
my $restartListFile = "/run/systemd/restart-list";
|
||
my $reloadListFile = "/run/systemd/reload-list";
|
||
|
||
my $action = shift @ARGV;
|
||
|
||
if (!defined $action || ($action ne "switch" && $action ne "boot" && $action ne "test")) {
|
||
print STDERR <<EOF;
|
||
Usage: $0 [switch|boot|test]
|
||
|
||
switch: make the configuration the boot default and activate now
|
||
boot: make the configuration the boot default
|
||
test: activate the configuration, but don\'t make it the boot default
|
||
EOF
|
||
exit 1;
|
||
}
|
||
|
||
die "This is not a NixOS installation (/etc/NIXOS is missing)!\n" unless -f "/etc/NIXOS";
|
||
|
||
# Install or update the bootloader.
|
||
if ($action eq "switch" || $action eq "boot") {
|
||
system("@installBootLoader@ @out@") == 0 or exit 1;
|
||
exit 0 if $action eq "boot";
|
||
}
|
||
|
||
# Check if we can activate the new configuration.
|
||
my $oldVersion = read_file("/run/current-system/init-interface-version", err_mode => 'quiet') // "";
|
||
my $newVersion = read_file("@out@/init-interface-version");
|
||
|
||
if ($newVersion ne $oldVersion) {
|
||
print STDERR <<EOF;
|
||
Warning: the new NixOS configuration has an ‘init’ that is
|
||
incompatible with the current configuration. The new configuration
|
||
won\'t take effect until you reboot the system.
|
||
EOF
|
||
exit 100;
|
||
}
|
||
|
||
# Ignore SIGHUP so that we're not killed if we're running on (say)
|
||
# virtual console 1 and we restart the "tty1" unit.
|
||
$SIG{PIPE} = "IGNORE";
|
||
|
||
sub getActiveUnits {
|
||
# FIXME: use D-Bus or whatever to query this, since parsing the
|
||
# output of list-units is likely to break.
|
||
my $lines = `@systemd@/bin/systemctl list-units --full`;
|
||
my $res = {};
|
||
foreach my $line (split '\n', $lines) {
|
||
chomp $line;
|
||
last if $line eq "";
|
||
$line =~ /^(\S+)\s+(\S+)\s+(\S+)\s+(\S+)\s/ or next;
|
||
next if $1 eq "UNIT";
|
||
$res->{$1} = { load => $2, state => $3, substate => $4 };
|
||
}
|
||
return $res;
|
||
}
|
||
|
||
sub parseFstab {
|
||
my ($filename) = @_;
|
||
my ($fss, $swaps);
|
||
foreach my $line (read_file($filename, err_mode => 'quiet')) {
|
||
chomp $line;
|
||
$line =~ s/#.*//;
|
||
next if $line =~ /^\s*$/;
|
||
my @xs = split / /, $line;
|
||
if ($xs[2] eq "swap") {
|
||
$swaps->{$xs[0]} = { options => $xs[3] // "" };
|
||
} else {
|
||
$fss->{$xs[1]} = { device => $xs[0], fsType => $xs[2], options => $xs[3] // "" };
|
||
}
|
||
}
|
||
return ($fss, $swaps);
|
||
}
|
||
|
||
sub parseUnit {
|
||
my ($filename) = @_;
|
||
my $info = {};
|
||
foreach my $line (read_file($filename)) {
|
||
# FIXME: not quite correct.
|
||
$line =~ /^([^=]+)=(.*)$/ or next;
|
||
$info->{$1} = $2;
|
||
}
|
||
return $info;
|
||
}
|
||
|
||
sub boolIsTrue {
|
||
my ($s) = @_;
|
||
return $s eq "yes" || $s eq "true";
|
||
}
|
||
|
||
# Stop all services that no longer exist or have changed in the new
|
||
# configuration.
|
||
my (@unitsToStop, @unitsToSkip);
|
||
my $activePrev = getActiveUnits;
|
||
while (my ($unit, $state) = each %{$activePrev}) {
|
||
my $baseUnit = $unit;
|
||
|
||
# Recognise template instances.
|
||
$baseUnit = "$1\@.$2" if $unit =~ /^(.*)@[^\.]*\.(.*)$/;
|
||
my $prevUnitFile = "/etc/systemd/system/$baseUnit";
|
||
my $newUnitFile = "@out@/etc/systemd/system/$baseUnit";
|
||
|
||
my $baseName = $baseUnit;
|
||
$baseName =~ s/\.[a-z]*$//;
|
||
|
||
if (-e $prevUnitFile && ($state->{state} eq "active" || $state->{state} eq "activating")) {
|
||
if (! -e $newUnitFile) {
|
||
push @unitsToStop, $unit;
|
||
}
|
||
|
||
elsif ($unit =~ /\.target$/) {
|
||
# Cause all active target units to be restarted below.
|
||
# This should start most changed units we stop here as
|
||
# well as any new dependencies (including new mounts and
|
||
# swap devices). FIXME: the suspend target is sometimes
|
||
# active after the system has resumed, which probably
|
||
# should not be the case. Just ignore it.
|
||
if ($unit ne "suspend.target" && $unit ne "hibernate.target") {
|
||
my $unitInfo = parseUnit($newUnitFile);
|
||
unless (boolIsTrue($unitInfo->{'RefuseManualStart'} // "false")) {
|
||
write_file($restartListFile, { append => 1 }, "$unit\n");
|
||
}
|
||
}
|
||
}
|
||
|
||
elsif (abs_path($prevUnitFile) ne abs_path($newUnitFile)) {
|
||
if ($unit eq "sysinit.target" || $unit eq "basic.target" || $unit eq "multi-user.target" || $unit eq "graphical.target") {
|
||
# Do nothing. These cannot be restarted directly.
|
||
} elsif ($unit =~ /\.mount$/) {
|
||
# Reload the changed mount unit to force a remount.
|
||
write_file($reloadListFile, { append => 1 }, "$unit\n");
|
||
} elsif ($unit =~ /\.socket$/ || $unit =~ /\.path$/) {
|
||
# FIXME: do something?
|
||
} else {
|
||
my $unitInfo = parseUnit($newUnitFile);
|
||
if (!boolIsTrue($unitInfo->{'X-RestartIfChanged'} // "true")
|
||
|| $unit eq "systemd-user-sessions.service"
|
||
|| $unit eq "systemd-journald.service")
|
||
{
|
||
push @unitsToSkip, $unit;
|
||
} else {
|
||
# If this unit has a corresponding socket unit,
|
||
# then stop the socket unit as well, and restart
|
||
# the socket instead of the service.
|
||
if ($unit =~ /\.service$/ && defined $activePrev->{"$baseName.socket"}) {
|
||
push @unitsToStop, "$baseName.socket";
|
||
write_file($restartListFile, { append => 1 }, "$baseName.socket\n");
|
||
}
|
||
|
||
# Record that this unit needs to be started below. We
|
||
# write this to a file to ensure that the service gets
|
||
# restarted if we're interrupted.
|
||
else {
|
||
write_file($restartListFile, { append => 1 }, "$unit\n");
|
||
}
|
||
|
||
push @unitsToStop, $unit;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
sub pathToUnitName {
|
||
my ($path) = @_;
|
||
die unless substr($path, 0, 1) eq "/";
|
||
return "-" if $path eq "/";
|
||
$path = substr($path, 1);
|
||
$path =~ s/\//-/g;
|
||
# FIXME: handle - and unprintable characters.
|
||
return $path;
|
||
}
|
||
|
||
sub unique {
|
||
my %seen;
|
||
my @res;
|
||
foreach my $name (@_) {
|
||
next if $seen{$name};
|
||
$seen{$name} = 1;
|
||
push @res, $name;
|
||
}
|
||
return @res;
|
||
}
|
||
|
||
# Compare the previous and new fstab to figure out which filesystems
|
||
# need a remount or need to be unmounted. New filesystems are mounted
|
||
# automatically by starting local-fs.target. FIXME: might be nicer if
|
||
# we generated units for all mounts; then we could unify this with the
|
||
# unit checking code above.
|
||
my ($prevFss, $prevSwaps) = parseFstab "/etc/fstab";
|
||
my ($newFss, $newSwaps) = parseFstab "@out@/etc/fstab";
|
||
foreach my $mountPoint (keys %$prevFss) {
|
||
my $prev = $prevFss->{$mountPoint};
|
||
my $new = $newFss->{$mountPoint};
|
||
my $unit = pathToUnitName($mountPoint) . ".mount";
|
||
if (!defined $new) {
|
||
# Filesystem entry disappeared, so unmount it.
|
||
push @unitsToStop, $unit;
|
||
} elsif ($prev->{fsType} ne $new->{fsType} || $prev->{device} ne $new->{device}) {
|
||
# Filesystem type or device changed, so unmount and mount it.
|
||
write_file($restartListFile, { append => 1 }, "$unit\n");
|
||
push @unitsToStop, $unit;
|
||
} elsif ($prev->{options} ne $new->{options}) {
|
||
# Mount options changes, so remount it.
|
||
write_file($reloadListFile, { append => 1 }, "$unit\n");
|
||
}
|
||
}
|
||
|
||
# Also handles swap devices.
|
||
foreach my $device (keys %$prevSwaps) {
|
||
my $prev = $prevSwaps->{$device};
|
||
my $new = $newSwaps->{$device};
|
||
if (!defined $new) {
|
||
# Swap entry disappeared, so turn it off. Can't use
|
||
# "systemctl stop" here because systemd has lots of alias
|
||
# units that prevent a stop from actually calling
|
||
# "swapoff".
|
||
print STDERR "stopping swap device: $device\n";
|
||
system("@utillinux@/sbin/swapoff", $device);
|
||
}
|
||
# FIXME: update swap options (i.e. its priority).
|
||
}
|
||
|
||
if (scalar @unitsToStop > 0) {
|
||
@unitsToStop = unique(@unitsToStop);
|
||
print STDERR "stopping the following units: ", join(", ", sort(@unitsToStop)), "\n";
|
||
system("@systemd@/bin/systemctl", "stop", "--", @unitsToStop); # FIXME: ignore errors?
|
||
}
|
||
|
||
print STDERR "NOT restarting the following units: ", join(", ", sort(@unitsToSkip)), "\n"
|
||
if scalar @unitsToSkip > 0;
|
||
|
||
# Activate the new configuration (i.e., update /etc, make accounts,
|
||
# and so on).
|
||
my $res = 0;
|
||
print STDERR "activating the configuration...\n";
|
||
system("@out@/activate", "@out@") == 0 or $res = 2;
|
||
|
||
# Restart systemd if necessary.
|
||
if (abs_path("/proc/1/exe") ne abs_path("@systemd@/lib/systemd/systemd")) {
|
||
print STDERR "restarting systemd...\n";
|
||
system("@systemd@/bin/systemctl", "daemon-reexec") == 0 or $res = 2;
|
||
}
|
||
|
||
# Forget about previously failed services.
|
||
system("@systemd@/bin/systemctl", "reset-failed");
|
||
|
||
# Make systemd reload its units.
|
||
system("@systemd@/bin/systemctl", "daemon-reload") == 0 or $res = 3;
|
||
|
||
# Start all active targets, as well as changed units we stopped above.
|
||
# The latter is necessary because some may not be dependencies of the
|
||
# targets (i.e., they were manually started). FIXME: detect units
|
||
# that are symlinks to other units. We shouldn't start both at the
|
||
# same time because we'll get a "Failed to add path to set" error from
|
||
# systemd.
|
||
my @start = unique("default.target", split('\n', read_file($restartListFile, err_mode => 'quiet') // ""));
|
||
print STDERR "starting the following units: ", join(", ", sort(@start)), "\n";
|
||
system("@systemd@/bin/systemctl", "start", "--", @start) == 0 or $res = 4;
|
||
unlink($restartListFile);
|
||
|
||
# Reload units that need it. This includes remounting changed mount
|
||
# units.
|
||
my @reload = unique(split '\n', read_file($reloadListFile, err_mode => 'quiet') // "");
|
||
if (scalar @reload > 0) {
|
||
print STDERR "reloading the following units: ", join(", ", sort(@reload)), "\n";
|
||
system("@systemd@/bin/systemctl", "reload", "--", @reload) == 0 or $res = 4;
|
||
unlink($reloadListFile);
|
||
}
|
||
|
||
# Signal dbus to reload its configuration.
|
||
system("@systemd@/bin/systemctl", "reload", "dbus.service");
|
||
|
||
# Print failed and new units.
|
||
my (@failed, @new, @restarting);
|
||
my $activeNew = getActiveUnits;
|
||
while (my ($unit, $state) = each %{$activeNew}) {
|
||
push @failed, $unit if $state->{state} eq "failed" || $state->{substate} eq "auto-restart";
|
||
push @new, $unit if $state->{state} ne "failed" && !defined $activePrev->{$unit};
|
||
}
|
||
|
||
print STDERR "the following new units were started: ", join(", ", sort(@new)), "\n"
|
||
if scalar @new > 0;
|
||
|
||
if (scalar @failed > 0) {
|
||
print STDERR "warning: the following units failed: ", join(", ", sort(@failed)), "\n";
|
||
foreach my $unit (@failed) {
|
||
print STDERR "\n";
|
||
system("COLUMNS=1000 @systemd@/bin/systemctl status --no-pager '$unit' >&2");
|
||
}
|
||
$res = 4;
|
||
}
|
||
|
||
exit $res;
|