2 files changed, 100 insertions, 59 deletions

diff --git a/lib/OpenSLX/Basics.pm b/lib/OpenSLX/Basics.pm
index 230bf72b..9af056e6 100644
--- a/lib/OpenSLX/Basics.pm
+++ b/lib/OpenSLX/Basics.pm
@@ -30,12 +30,10 @@ $VERSION = 1.01;
     &vlog
     &checkParams
     &instantiateClass
-    &addCleanupFunction &removeCleanupFunction
 );
 
 our (%openslxConfig, %cmdlineConfig, %openslxPath);
 
-use sigtrap qw( die normal-signals error-signals );
 use subs qw(die warn);
 
 use open ':utf8';
@@ -139,8 +137,6 @@ my %openslxCmdlineArgs = (
     'verbose-level=i' => \$cmdlineConfig{'verbose-level'},
 );
 
-my %cleanupFunctions;
-
 # filehandle used for logging:
 my $openslxLog = *STDERR;
 
@@ -313,27 +309,20 @@ sub callInSubprocess
 
     my $pid = fork();
     if (!$pid) {
-
-        # child...
-        # ...execute the given function and exit:
-        my $ok = eval { $childFunc->(); 1 };
-        if (!$ok) {
-            print STDERR "*** $@";
-            exit 5;
-        }
+        # child -> execute the given function and exit:
+        eval { $childFunc->(); 1 }
+            or die $@;
         exit 0;
     }
 
-    # parent...
-    # ...pass on interrupt- and terminate-signals to child...
-    local $SIG{INT}  = sub { kill 'INT',  $pid; waitpid($pid, 0); exit $? };
-    local $SIG{TERM} = sub { kill 'TERM', $pid; waitpid($pid, 0); exit $? };
+    # parent -> pass on interrupt- and terminate-signals to child ...
+    $SIG{INT}  = sub { kill 'INT',  $pid; };
+    $SIG{TERM} = sub { kill 'TERM', $pid; };
 
-    # ...and wait for child to do its work:
+    # ... and wait until child has done its work
     waitpid($pid, 0);
-    if ($?) {
-        exit $?;
-    }
+    exit $? if $?;
+
     return;
 }
 
@@ -355,36 +344,6 @@ sub executeInSubprocess
 }
 
 # ------------------------------------------------------------------------------
-sub addCleanupFunction
-{
-    my $name = shift;
-    my $func = shift;
-
-    $cleanupFunctions{$name} = $func;
-    return;
-}
-
-# ------------------------------------------------------------------------------
-sub removeCleanupFunction
-{
-    my $name = shift;
-
-    delete $cleanupFunctions{$name};
-    return;
-}
-
-# ------------------------------------------------------------------------------
-sub invokeCleanupFunctions
-{
-    my @funcNames = keys %cleanupFunctions;
-    foreach my $name (@funcNames) {
-        vlog(2, "invoking cleanup function '$name'...");
-        $cleanupFunctions{$name}->();
-    }
-    return;
-}
-
-# ------------------------------------------------------------------------------
 sub slxsystem
 {
     vlog(2, _tr("executing: %s", join ' ', @_));
@@ -426,7 +385,6 @@ sub warn
 # ------------------------------------------------------------------------------
 sub confess
 {
-    invokeCleanupFunctions();
     _doThrowOrWarn('confess', @_);
     return;
 }
@@ -434,7 +392,6 @@ sub confess
 # ------------------------------------------------------------------------------
 sub croak
 {
-    invokeCleanupFunctions();
     _doThrowOrWarn('croak', @_);
     return;
 }
@@ -442,7 +399,6 @@ sub croak
 # ------------------------------------------------------------------------------
 sub die
 {
-    invokeCleanupFunctions();
     _doThrowOrWarn('die', @_);
     return;
 }
@@ -636,10 +592,4 @@ sub instantiateClass
     return $class->new;
 }
 
-# ------------------------------------------------------------------------------
-END 
-{
-    invokeCleanupFunctions() if %cleanupFunctions;
-}
-
 1;
diff --git a/lib/OpenSLX/ScopedResource.pm b/lib/OpenSLX/ScopedResource.pm
new file mode 100644
index 00000000..c905b50a
--- /dev/null
+++ b/lib/OpenSLX/ScopedResource.pm
@@ -0,0 +1,91 @@
+# Copyright (c) 2008 - OpenSLX GmbH
+#
+# This program is free software distributed under the GPL version 2.
+# See http://openslx.org/COPYING
+#
+# If you have any feedback please consult http://openslx.org/feedback and
+# send your suggestions, praise, or complaints to feedback@openslx.org
+#
+# General information about OpenSLX can be found at http://openslx.org/
+# -----------------------------------------------------------------------------
+# ScopedResource.pm
+#    - a helper class that releases resources if the object leaves scope
+# -----------------------------------------------------------------------------
+package OpenSLX::ScopedResource;
+
+use strict;
+use warnings;
+
+our $VERSION = 1.01;        # API-version . implementation-version
+
+# make sure that we catch any signals in order to properly released scoped
+# resources
+use sigtrap qw( die normal-signals error-signals );
+
+use OpenSLX::Basics;
+
+sub new
+{
+    my $class = shift;
+    my $params = shift;
+    
+    checkParams($params, {
+        name    => '!',
+        acquire => '!',
+        release => '!',
+    });
+
+    my $self = {
+        name    => $params->{name},
+        owner   => 0,
+        acquire => $params->{acquire},
+        release => $params->{release},
+    };
+    
+    bless $self, $class;
+    
+    $self->acquire();
+    
+    return $self;
+}
+
+sub acquire
+{
+    my $self = shift;
+
+    # acquire the resource and set ourselves as owner
+    if ($self->{acquire}->()) {
+        vlog(1, "process $$ acquired resource $self->{name}");
+        $self->{owner} = $$;
+    }
+}
+
+sub release
+{
+    my $self = shift;
+
+    # only release the resource if invoked by the owning process
+    vlog(3, "process $$ tries to release resource $self->{name}");
+    return if $self->{owner} != $$;
+    
+    # release the resource and unset owner
+    if ($self->{release}->()) {
+        vlog(1, "process $$ released resource $self->{name}");
+        $self->{owner} = 0;
+    }
+}
+
+sub DESTROY
+{
+    my $self = shift;
+    
+    $self->release();
+    
+    # remove references to functions, in order to release any closures
+    $self->{acquire} = undef;
+    $self->{release} = undef;
+    
+    return;
+}
+
+1;