tests: use Cygwin/msys PIDs for stunnel and sshd on Windows

Since the Windows versions of both programs would write Windows
PIDs to their pidfiles which we cannot handle, we need to use
our known perl.exe Cygwin/msys PID together with exec() in order
to tie the spawned processes to the existance of our perl.exe

The perl.exe that is executing secureserver.pl and sshserver.pl
has a Cygwin/msys PID, because it is started inside Cygwin/msys.

Related to #5188

1 files changed, 31 insertions, 3 deletions

diff --git a/tests/sshserver.pl b/tests/sshserver.pl
index 084b4a83c..1874b9388 100644
--- a/tests/sshserver.pl
+++ b/tests/sshserver.pl
@@ -535,7 +535,9 @@ push @cfgarr, '#';
 push @cfgarr, "AuthorizedKeysFile $clipubkeyf_config";
 push @cfgarr, "AuthorizedKeysFile2 $clipubkeyf_config";
 push @cfgarr, "HostKey $hstprvkeyf_config";
-push @cfgarr, "PidFile $pidfile_config";
+if ($sshdid !~ /OpenSSH-Windows/) {
+    push @cfgarr, "PidFile $pidfile_config";
+}
 push @cfgarr, '#';
 push @cfgarr, "Port $port";
 push @cfgarr, "ListenAddress $listenaddr";
@@ -1098,12 +1100,38 @@ if($error) {
 }
 @cfgarr = ();
 
+#***************************************************************************
+# Prepare command line of ssh server daemon
+#
+my $cmd = "\"$sshd\" -e -D -f $sshdconfig > $sshdlog 2>&1";
+logmsg "SCP/SFTP server listening on port $port" if($verbose);
+logmsg "RUN: $cmd" if($verbose);
+
+#***************************************************************************
+# Start the ssh server daemon on Windows without forking it
+#
+if ($sshdid =~ /OpenSSH-Windows/) {
+    # Fake pidfile for ssh server on Windows.
+    if(open(OUT, ">$pidfile")) {
+        print OUT $$ . "\n";
+        close(OUT);
+    }
+
+    # Put an "exec" in front of the command so that the child process
+    # keeps this child's process ID by being tied to the spawned shell.
+    exec("exec $cmd") || die "Can't exec() $cmd: $!";
+    # exec() will create a new process, but ties the existance of the
+    # new process to the parent waiting perl.exe and sh.exe processes.
+
+    # exec() should never return back here to this process. We protect
+    # ourselves by calling die() just in case something goes really bad.
+    die "error: exec() has returned";
+}
 
 #***************************************************************************
 # Start the ssh server daemon without forking it
 #
-logmsg "SCP/SFTP server listening on port $port" if($verbose);
-my $rc = system "\"$sshd\" -e -D -f $sshdconfig > $sshdlog 2>&1";
+my $rc = system($cmd);
 if($rc == -1) {
     logmsg "\"$sshd\" failed with: $!";
 }