X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FObject%2FRemote%2FConnection.pm;h=b7c8903c3c9f989a3b13628660f3b153324dbc6f;hb=b49a063d7885c23278585e52c3066c791f8934f2;hp=4d46618c82c26cb9227dd0afa07c8a9af00a517e;hpb=f8080c1c188fa6c4589ffcad8793e0cf7a8d4bdb;p=scpubgit%2FObject-Remote.git

diff --git a/lib/Object/Remote/Connection.pm b/lib/Object/Remote/Connection.pm
index 4d46618..b7c8903 100644
--- a/lib/Object/Remote/Connection.pm
+++ b/lib/Object/Remote/Connection.pm
@@ -1,26 +1,62 @@
 package Object::Remote::Connection;
 
+use Object::Remote::Logging qw (:log :dlog get_router);
 use Object::Remote::Future;
 use Object::Remote::Null;
 use Object::Remote::Handle;
 use Object::Remote::CodeContainer;
 use Object::Remote::GlobProxy;
 use Object::Remote::GlobContainer;
-use Object::Remote::Logging qw (:log :dlog);
 use Object::Remote::Tied;
 use Object::Remote;
 use Symbol;
 use IO::Handle;
+use POSIX ":sys_wait_h";
 use Module::Runtime qw(use_module);
 use Scalar::Util qw(weaken blessed refaddr openhandle);
 use JSON::PP qw(encode_json);
 use Moo;
 
-our $DEBUG = !!$ENV{OBJECT_REMOTE_DEBUG};
-#numbering each connection allows it to be
-#tracked along with file handles in
-#the logs
-BEGIN { our $NEXT_CONNECTION_ID = 0 }
+BEGIN { 
+  get_router()->exclude_forwarding;
+
+  #this will reap child processes as soon
+  #as they are done executing so the process
+  #table cleans up as fast as possible but
+  #anything that needs to call waitpid()
+  #in the future to get the exit value of
+  #a child will get trash results if
+  #the signal handler was running. 
+  #If creating a child and getting the
+  #exit value is required then set
+  #a localized version of the signal
+  #handler for CHLD to be 'IGNORE'
+  #in the smallest block possible
+  #and outside the block send
+  #the process a CHLD signal
+  #to reap anything that may
+  #have exited while blocked
+  #in waitpid() 
+  $SIG{CHLD} = sub { 
+    my $kid; 
+    log_trace { "CHLD signal handler is executing" };
+    do {
+      $kid = waitpid(-1, WNOHANG);
+      log_debug { "waitpid() returned '$kid'" };
+    } while $kid > 0;
+    log_trace { "CHLD signal handler is done" };
+  };
+  
+  $SIG{PIPE} = sub { log_debug { "Got a PIPE signal" } };      
+}
+
+END {
+  log_debug { "Killing all child processes in the process group" };
+    
+  #send SIGINT to the process group for our children
+  kill(1, -2);
+}
+
 has _id => ( is => 'ro', required => 1, default => sub { our $NEXT_CONNECTION_ID++ } );
 
 has send_to_fh => (
@@ -41,33 +77,15 @@ has read_channel => (
     weaken($self);
     $ch->on_line_call(sub { $self->_receive(@_) });
     $ch->on_close_call(sub { 
-        log_trace { "invoking 'done' on on_close handler for connection id '$id'" }; 
-        $self->on_close->done(@_);
+      log_trace { "invoking 'done' on on_close handler for connection id '$id'" }; 
+      $self->on_close->done(@_);
     });
   },
 );
 
-#TODO properly fix this bug -
-#trigger can't ever be invoked with a default
-#value and the on_close attribute is read only....
-#the future never gets the on_done handler
-#installed 
-sub BUILD {
-  my ($self) = @_; 
-  $self->on_close(CPS::Future->new);  
-}
-
 has on_close => (
-  is => 'rw', default => sub { CPS::Future->new },
-  trigger => sub {
-    my ($self, $f) = @_;
-    Dlog_trace { "trigger for on_close has been invoked for connection $_" } $self->_id;
-    weaken($self);
-    $f->on_done(sub {
-      Dlog_trace { "failing all of the outstanding futures for connection $_" } $self->_id;
-      $self->_fail_outstanding("Connection lost: " . ($f->get)[0]);
-    });
-  }
+  is => 'rw', default => sub { $_[0]->_install_future_handlers(CPS::Future->new) },
+  trigger => \&_install_future_handlers,
 );
 
 has child_pid => (is => 'ro');
@@ -84,22 +102,45 @@ has remote_objects_by_id => (
 
 has outstanding_futures => (is => 'ro', default => sub { {} });
 
+has _json => (
+  is => 'lazy',
+  handles => {
+    _deserialize => 'decode',
+    _encode => 'encode',
+  },
+);
+
+after BUILD => sub {
+  my ($self) = @_; 
+  
+  return unless defined $self->child_pid; 
+  
+  log_debug { "Setting process group of child process" };
+  
+  setpgrp($self->child_pid, 1);
+};
+
+sub BUILD { }
+
 sub _fail_outstanding {
   my ($self, $error) = @_;
   Dlog_debug { "Failing outstanding futures with '$error' for connection $_" } $self->_id;
   my $outstanding = $self->outstanding_futures;
-  $_->fail($error) for values %$outstanding;
+  $_->fail("$error\n") for values %$outstanding;
   %$outstanding = ();
   return;
 }
 
-has _json => (
-  is => 'lazy',
-  handles => {
-    _deserialize => 'decode',
-    _encode => 'encode',
-  },
-);
+sub _install_future_handlers {
+    my ($self, $f) = @_;
+    Dlog_trace { "trigger for on_close has been invoked for connection $_" } $self->_id;
+    weaken($self);
+    $f->on_done(sub {
+      Dlog_trace { "failing all of the outstanding futures for connection $_" } $self->_id;
+      $self->_fail_outstanding("Object::Remote connection lost: " . ($f->get)[0]);
+    });
+    return $f; 
+};
 
 sub _id_to_remote_object {
   my ($self, $id) = @_;
@@ -140,37 +181,60 @@ sub _build__json {
     }
   )->filter_json_single_key_object(
     __remote_tied_hash__ => sub {
-        my %tied_hash;
-        tie %tied_hash, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
-        return \%tied_hash;
+      my %tied_hash;
+      tie %tied_hash, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
+      return \%tied_hash;
     }
   )->filter_json_single_key_object(
     __remote_tied_array__ => sub {
-        my @tied_array;
-        tie @tied_array, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
-        return \@tied_array;
+      my @tied_array;
+      tie @tied_array, 'Object::Remote::Tied', $self->_id_to_remote_object(@_);
+      return \@tied_array;
     }
   ); 
 }
 
+sub _load_if_possible {
+  my ($class) = @_; 
+
+  use_module($class); 
+
+  if ($@) {
+    log_debug { "Attempt at loading '$class' failed with '$@'" };
+  }
+
+}
+
 BEGIN {
   unshift our @Guess, sub { blessed($_[0]) ? $_[0] : undef };
-  eval { require Object::Remote::Connector::Local };
-  eval { require Object::Remote::Connector::LocalSudo };
-  eval { require Object::Remote::Connector::SSH };
-  eval { require Object::Remote::Connector::UNIX };
+  map _load_if_possible($_), qw(
+    Object::Remote::Connector::Local
+    Object::Remote::Connector::LocalSudo
+    Object::Remote::Connector::SSH
+    Object::Remote::Connector::UNIX
+  ); 
 }
 
-sub new_from_spec {
-  my ($class, $spec) = @_;
-  return $spec if blessed $spec;
-  Dlog_debug { "creating a new connection from spec" };
+sub conn_from_spec {
+  my ($class, $spec, @args) = @_;
   foreach my $poss (do { our @Guess }) {
-    if (my $conn = $poss->($spec)) {
-      return $conn->maybe::start::connect;
+    if (my $conn = $poss->($spec, @args)) {
+      return $conn;
     }
   }
-  die "Couldn't figure out what to do with ${spec}";
+  
+  return undef;
+}
+
+sub new_from_spec {
+  my ($class, $spec) = @_;
+  return $spec if blessed $spec;
+  my $conn = $class->conn_from_spec($spec); 
+  
+  die "Couldn't figure out what to do with ${spec}"
+    unless defined $conn;
+    
+  return $conn->maybe::start::connect;  
 }
 
 sub remote_object {
@@ -267,24 +331,20 @@ sub _send {
   Dlog_trace { "Starting to serialize data in argument to _send for connection $_" } $self->_id;
   my $serialized = $self->_serialize($to_send)."\n";
   Dlog_trace { my $l = length($serialized); "serialization is completed; sending '$l' characters of serialized data to $_" } $fh;
-  #TODO this is very risky for deadlocks unless it's set to non-blocking and then with out extra
-  #logic it could easily do short-writes to the remote side - how about taking this entire buffer
-  #and having the run loop send it to the file handle so this doesn't block while the sending
-  #is happening? 
   my $ret; 
   eval { 
-      local($SIG{PIPE}) = 'IGNORE';
-      die "filehandle is not open" unless openhandle($fh);
-      log_trace { "file handle has passed openhandle() test; printing to it" };
-      $ret = print $fh $serialized;
-      die "print was not successful: $!" unless defined $ret
+    #TODO this should be converted over to a non-blocking ::WriteChannel class
+    die "filehandle is not open" unless openhandle($fh);
+    log_trace { "file handle has passed openhandle() test; printing to it" };
+    $ret = print $fh $serialized;
+    die "print was not successful: $!" unless defined $ret
   };
-  
+    
   if ($@) {
-      Dlog_debug { "exception encountered when trying to write to file handle $_: $@" } $fh;
-      my $error = $@; chomp($error);
-      $self->on_close->done("could not write to file handle: $error") unless $self->on_close->is_ready;
-      return; 
+    Dlog_debug { "exception encountered when trying to write to file handle $_: $@" } $fh;
+    my $error = $@; chomp($error);
+    $self->on_close->done("could not write to file handle: $error") unless $self->on_close->is_ready;
+    return; 
   }
       
   return $ret; 
@@ -295,7 +355,6 @@ sub _serialize {
   local our @New_Ids = (-1);
   return eval {
     my $flat = $self->_encode($self->_deobjectify($data));
-    warn "$$ >>> ${flat}\n" if $DEBUG;
     $flat;
   } || do {
     my $err = $@; # won't get here if the eval doesn't die
@@ -361,7 +420,6 @@ sub _deobjectify {
 
 sub _receive {
   my ($self, $flat) = @_;
-  warn "$$ <<< $flat\n" if $DEBUG;
   Dlog_trace { my $l = length($flat); "Starting to deserialize $l characters of data for connection $_" } $self->_id;
   my ($type, @rest) = eval { @{$self->_deserialize($flat)} }
     or do { warn "Deserialize failed for ${flat}: $@"; return };