128 lines
4.0 KiB
Perl
128 lines
4.0 KiB
Perl
package SocketActivation;
|
|
# vim:ts=4:sw=4:expandtab
|
|
|
|
use IO::Socket::UNIX; # core
|
|
use Cwd qw(abs_path); # core
|
|
use POSIX; # core
|
|
use AnyEvent::Handle; # not core
|
|
use Exporter 'import';
|
|
use v5.10;
|
|
|
|
our @EXPORT = qw(activate_i3);
|
|
|
|
#
|
|
# Starts i3 using socket activation. Creates a listening socket (with bind +
|
|
# listen) which is then passed to i3, who in turn calls accept and handles the
|
|
# requests.
|
|
#
|
|
# Since the kernel buffers the connect, the parent process can connect to the
|
|
# socket immediately after forking. It then sends a request and waits until it
|
|
# gets an answer. Obviously, i3 has to be initialized to actually answer the
|
|
# request.
|
|
#
|
|
# This way, we can wait *precisely* the amount of time which i3 waits to get
|
|
# ready, which is a *HUGE* speed gain (and a lot more robust) in comparison to
|
|
# using sleep() with a fixed amount of time.
|
|
#
|
|
# unix_socket_path: Location of the socket to use for the activation
|
|
# display: X11 $ENV{DISPLAY}
|
|
# configfile: path to the configuration file to use
|
|
# logpath: path to the logfile to which i3 will append
|
|
# cv: an AnyEvent->condvar which will be triggered once i3 is ready
|
|
#
|
|
sub activate_i3 {
|
|
my %args = @_;
|
|
|
|
# remove the old unix socket
|
|
unlink($args{unix_socket_path});
|
|
|
|
# pass all file descriptors up to three to the children.
|
|
# we need to set this flag before opening the socket.
|
|
open(my $fdtest, '<', '/dev/null');
|
|
$^F = fileno($fdtest);
|
|
close($fdtest);
|
|
my $socket = IO::Socket::UNIX->new(
|
|
Listen => 1,
|
|
Local => $args{unix_socket_path},
|
|
);
|
|
|
|
my $pid = fork;
|
|
if (!defined($pid)) {
|
|
die "could not fork()";
|
|
}
|
|
if ($pid == 0) {
|
|
$ENV{LISTEN_PID} = $$;
|
|
$ENV{LISTEN_FDS} = 1;
|
|
delete $ENV{DESKTOP_STARTUP_ID};
|
|
$ENV{DISPLAY} = $args{display};
|
|
$ENV{PATH} = join(':',
|
|
'../i3-nagbar',
|
|
'../i3-msg',
|
|
'../i3-config-wizard',
|
|
'../i3bar',
|
|
'..',
|
|
$ENV{PATH}
|
|
);
|
|
# Only pass file descriptors 0 (stdin), 1 (stdout), 2 (stderr) and
|
|
# 3 (socket) to the child.
|
|
$^F = 3;
|
|
|
|
# If the socket does not use file descriptor 3 by chance already, we
|
|
# close fd 3 and dup2() the socket to 3.
|
|
if (fileno($socket) != 3) {
|
|
POSIX::close(3);
|
|
POSIX::dup2(fileno($socket), 3);
|
|
}
|
|
|
|
# Construct the command to launch i3. Use maximum debug level, disable
|
|
# the interactive signalhandler to make it crash immediately instead.
|
|
my $i3cmd = abs_path("../i3") . " -V -d all --disable-signalhandler";
|
|
|
|
if ($args{valgrind}) {
|
|
$i3cmd =
|
|
qq|valgrind -v --log-file="$args{outdir}/valgrind.log" | .
|
|
qq|--leak-check=full --track-origins=yes --num-callers=20 | .
|
|
qq|--tool=memcheck -- $i3cmd|;
|
|
}
|
|
|
|
# Append to $args{logpath} instead of overwriting because i3 might be
|
|
# run multiple times in one testcase.
|
|
my $cmd = "exec $i3cmd -c $args{configfile} >>$args{logpath} 2>&1";
|
|
|
|
# We need to use the shell due to using output redirections.
|
|
exec '/bin/sh', '-c', $cmd;
|
|
|
|
# if we are still here, i3 could not be found or exec failed. bail out.
|
|
exit 1;
|
|
}
|
|
|
|
# close the socket, the child process should be the only one which keeps a file
|
|
# descriptor on the listening socket.
|
|
$socket->close;
|
|
|
|
# We now connect (will succeed immediately) and send a request afterwards.
|
|
# As soon as the reply is there, i3 is considered ready.
|
|
my $cl = IO::Socket::UNIX->new(Peer => $args{unix_socket_path});
|
|
my $hdl;
|
|
$hdl = AnyEvent::Handle->new(
|
|
fh => $cl,
|
|
on_error => sub {
|
|
$hdl->destroy;
|
|
$args{cv}->send(0);
|
|
});
|
|
|
|
# send a get_tree message without payload
|
|
$hdl->push_write('i3-ipc' . pack("LL", 0, 4));
|
|
|
|
# wait for the reply
|
|
$hdl->push_read(chunk => 1, => sub {
|
|
my ($h, $line) = @_;
|
|
$args{cv}->send(1);
|
|
undef $hdl;
|
|
});
|
|
|
|
return $pid;
|
|
}
|
|
|
|
1
|