Blocking function

git-svn-id: https://svn.fhem.de/fhem/trunk@2384 2b470e98-0d58-463d-a4d8-8e2adae1ed80

fhem/FHEM/Blocking.pm

@@ -0,0 +1,76 @@
+##############################################
+# $Id: $
+package main;
+
+use strict;
+use warnings;
+use IO::Socket::INET;
+
+sub BlockingCall($$$$);
+
+
+### Usage:
+sub TestBlocking() { BlockingCall("DoSleep", 5, "SleepDone", 8); }
+sub DoSleep($)     { sleep(shift); return "I'm done"; }
+sub SleepDone($)   { Log 1, "SleepDone: " . shift; }
+
+=pod
+=cut
+
+
+sub
+BlockingCall($$$$)
+{
+  my ($blockingFn, $arg, $finishFn, $timeout) = @_;
+
+  my $pid = fork;
+  if(!defined($pid)) {
+    Log 1, "Cannot fork: $!";
+    return undef;
+  }
+
+  if($pid) {
+    InternalTimer(gettimeofday()+$timeout, "BlockingKill", $pid, 0)
+      if($timeout);
+    return $pid;
+  }
+
+  # Child here
+  no strict "refs";
+  my $ret = &{$blockingFn}($arg);
+  use strict "refs";
+
+  # Look for the telnetport
+  my $tp;
+  foreach my $d (sort keys %defs) {
+    my $h = $defs{$d};
+    next if(!$h->{TYPE} || $h->{TYPE} ne "telnet" || $h->{TEMPORARY});
+    next if($attr{$d}{SSL} || $attr{$d}{password});
+    next if($h->{DEF} =~ m/IPV6/);
+    $tp = $d;
+    last;
+  }
+
+  if(!$tp) {
+    Log 1, "CallBlockingFn: No telnet port found for sending the data back.";
+    exit(0);
+  }
+
+  # Write the data back, calling the function
+  my $addr = "localhost:$defs{$tp}{PORT}";
+  my $client = IO::Socket::INET->new(PeerAddr => $addr);
+  Log 1, "CallBlockingFn: Can't connect to $addr\n" if(!$client);
+  $ret =~ s/'/\\'/g;
+  syswrite($client, "{$finishFn('$ret')}\n");
+  exit(0);
+}
+
+sub
+BlockingKill($)
+{
+  my $pid = shift;
+  Log 1, "Terminated $pid" if($pid && kill(9, $pid));
+}
+
+
+1;