1 package SocketActivation;
2 # vim:ts=4:sw=4:expandtab
6 use IO::Socket::UNIX; # core
7 use Cwd qw(abs_path); # core
8 use POSIX qw(:fcntl_h); # core
9 use AnyEvent::Handle; # not core
10 use AnyEvent::Util; # not core
11 use Exporter 'import';
14 our @EXPORT = qw(activate_i3);
17 # Starts i3 using socket activation. Creates a listening socket (with bind +
18 # listen) which is then passed to i3, who in turn calls accept and handles the
21 # Since the kernel buffers the connect, the parent process can connect to the
22 # socket immediately after forking. It then sends a request and waits until it
23 # gets an answer. Obviously, i3 has to be initialized to actually answer the
26 # This way, we can wait *precisely* the amount of time which i3 waits to get
27 # ready, which is a *HUGE* speed gain (and a lot more robust) in comparison to
28 # using sleep() with a fixed amount of time.
30 # unix_socket_path: Location of the socket to use for the activation
31 # display: X11 $ENV{DISPLAY}
32 # configfile: path to the configuration file to use
33 # logpath: path to the logfile to which i3 will append
34 # cv: an AnyEvent->condvar which will be triggered once i3 is ready
39 # remove the old unix socket
40 unlink($args{unix_socket_path});
42 my $socket = IO::Socket::UNIX->new(
44 Local => $args{unix_socket_path},
49 die "could not fork()";
52 $ENV{LISTEN_PID} = $$;
54 delete $ENV{DESKTOP_STARTUP_ID};
56 # $SHELL could be set to fish, which will horribly break running shell
57 # commands via i3’s exec feature. This happened e.g. when having
58 # “set-option -g default-shell "/usr/bin/fish"” in ~/.tmux.conf
60 unless ($args{dont_create_temp_dir}) {
61 $ENV{XDG_RUNTIME_DIR} = '/tmp/i3-testsuite/';
62 mkdir $ENV{XDG_RUNTIME_DIR};
64 $ENV{DISPLAY} = $args{display};
65 $ENV{PATH} = join(':',
68 '../i3-config-wizard',
74 # We are about to exec, but we did not modify $^F to include $socket
75 # when creating the socket (because the file descriptor could have a
76 # number != 3 which would lead to i3 leaking a file descriptor). This
77 # caused Perl to set the FD_CLOEXEC flag, which would close $socket on
78 # exec(), effectively *NOT* passing $socket to the new process.
79 # Therefore, we explicitly clear FD_CLOEXEC (the only flag right now)
80 # by setting the flags to 0.
81 POSIX::fcntl($socket, F_SETFD, 0) or die "Could not clear fd flags: $!";
83 # If the socket does not use file descriptor 3 by chance already, we
84 # close fd 3 and dup2() the socket to 3.
85 if (fileno($socket) != 3) {
87 POSIX::dup2(fileno($socket), 3);
88 POSIX::close(fileno($socket));
91 # Make sure no file descriptors are open. Strangely, I got an open file
92 # descriptor pointing to AnyEvent/Impl/EV.pm when testing.
93 AnyEvent::Util::close_all_fds_except(0, 1, 2, 3);
95 # Construct the command to launch i3. Use maximum debug level, disable
96 # the interactive signalhandler to make it crash immediately instead.
97 # Also disable logging to SHM since we redirect the logs anyways.
98 # Force Xinerama because we use Xdmx for multi-monitor tests.
99 my $i3cmd = abs_path("../i3") . q| -V -d all --disable-signalhandler| .
100 q| --shmlog-size=0 --force-xinerama|;
103 my $outdir = $args{outdir};
104 my $test = $args{testname};
106 if ($args{restart}) {
107 $i3cmd .= ' -L ' . abs_path('restart-state.golden');
110 if ($args{valgrind}) {
112 qq|valgrind --log-file="$outdir/valgrind-for-$test.log" | .
113 qq|--suppressions="./valgrind.supp" | .
114 qq|--leak-check=full --track-origins=yes --num-callers=20 | .
115 qq|--tool=memcheck -- $i3cmd|;
118 my $logfile = "$outdir/i3-log-for-$test";
119 # Append to $logfile instead of overwriting because i3 might be
120 # run multiple times in one testcase.
121 my $cmd = "exec $i3cmd -c $args{configfile} >>$logfile 2>&1";
124 my $out = "$outdir/strace-for-$test.log";
126 # We overwrite LISTEN_PID with the correct process ID to make
127 # socket activation work (LISTEN_PID has to match getpid(),
128 # otherwise the LISTEN_FDS will be treated as a left-over).
129 $cmd = qq|strace -fF -s2048 -v -o "$out" -- | .
130 'sh -c "export LISTEN_PID=\$\$; ' . $cmd . '"';
134 my $out = "$outdir/xtrace-for-$test.log";
136 # See comment in $args{strace} branch.
137 $cmd = qq|xtrace -n -o "$out" -- | .
138 'sh -c "export LISTEN_PID=\$\$; ' . $cmd . '"';
141 # We need to use the shell due to using output redirections.
142 exec '/bin/sh', '-c', $cmd;
144 # if we are still here, i3 could not be found or exec failed. bail out.
148 # close the socket, the child process should be the only one which keeps a file
149 # descriptor on the listening socket.
152 # We now connect (will succeed immediately) and send a request afterwards.
153 # As soon as the reply is there, i3 is considered ready.
154 my $cl = IO::Socket::UNIX->new(Peer => $args{unix_socket_path});
156 $hdl = AnyEvent::Handle->new(
163 # send a get_tree message without payload
164 $hdl->push_write('i3-ipc' . pack("LL", 0, 4));
167 $hdl->push_read(chunk => 1, => sub {