From 4ddd7dfef4a249617ffb97e4210a18b74f0785d5 Mon Sep 17 00:00:00 2001
From: Peter Donald <donaldp@apache.org>
Date: Sat, 2 Mar 2002 01:07:13 +0000
Subject: [PATCH] Rework it so that ExecManager does not shutdown streams.

Important when you pass in System.out/System.err or want to do something
special to stream after processing.

Submitted By: Darrell DeBoer <darrell@apache.org>


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271649 13f79535-47bb-0310-9956-ffa450edef68
---
 .../nativelib/impl/DefaultExecManager.java    |  2 +-
 .../aut/nativelib/impl/Environment.java       | 17 +++++---
 .../aut/nativelib/impl/ProcessMonitor.java    | 42 +++++++++++++++++--
 3 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/DefaultExecManager.java b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/DefaultExecManager.java
index 8209371d1..345e89dd9 100644
--- a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/DefaultExecManager.java
+++ b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/DefaultExecManager.java
@@ -115,7 +115,7 @@ public class DefaultExecManager
         final CommandLauncher launcher = getLauncher( command );
         final Process process = launcher.exec( command );
         final ProcessMonitor monitor =
-            new ProcessMonitor( process, input, output, error, timeout );
+            new ProcessMonitor( process, input, output, error, timeout, false );
 
         final Thread thread = new Thread( monitor, "ProcessMonitor" );
         thread.start();
diff --git a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/Environment.java b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/Environment.java
index c903fb797..2452c719d 100644
--- a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/Environment.java
+++ b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/Environment.java
@@ -19,6 +19,7 @@ import org.apache.aut.nativelib.ExecManager;
 import org.apache.aut.nativelib.ExecMetaData;
 import org.apache.aut.nativelib.Os;
 import org.apache.avalon.excalibur.util.StringUtil;
+import org.apache.avalon.excalibur.io.IOUtil;
 
 /**
  * This is the class that can be used to retrieve the environment
@@ -157,13 +158,17 @@ final class Environment
         final ExecMetaData metaData = new ExecMetaData( command, null, workingDirectory );
 
         final ByteArrayOutputStream output = new ByteArrayOutputStream();
-        final int retval = m_execManager.execute( metaData, null, output, output, 0 );
-        if( retval != 0 )
-        {
-            // Just try to use what we got
-        }
+        try {
+            final int retval = m_execManager.execute( metaData, null, output, output, 0 );
+            if( retval != 0 )
+            {
+                // Just try to use what we got
+            }
 
-        return output.toString();
+            return output.toString();
+        } finally {
+            IOUtil.shutdownStream( output );
+        }
     }
 
     /**
diff --git a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/ProcessMonitor.java b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/ProcessMonitor.java
index dc2423d5f..e56313d84 100644
--- a/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/ProcessMonitor.java
+++ b/proposal/myrmidon/src/java/org/apache/aut/nativelib/impl/ProcessMonitor.java
@@ -72,11 +72,33 @@ class ProcessMonitor
      */
     private final OutputStream m_error;
 
+    /**
+     * Specifies whether the monitor should shutdown
+     * input, output and error Streams when it finishes execution.
+     * This should be set to <code>true</code> for processes which
+     * will run asynchronously.
+     */
+    private final boolean m_shutdownStreams;
+
+    /**
+     * Creates a monitor for a given {@link java.lang.Process}, which pipes
+     * input from the given input stream to the process, and pipes the process
+     * output to the given OutputStreams.
+     *
+     * @param process the Process to be monitored
+     * @param input is read into the Process' stdin
+     * @param output receives the Process' stdout
+     * @param error receives the Process' stderr
+     * @param timeoutDuration how long to let the Process run before killing it.
+     * @param shutdownStreams specifies if the monitor should shutdown the
+     *             streams when the Process exits.
+     */
     public ProcessMonitor( final Process process,
                            final InputStream input,
                            final OutputStream output,
                            final OutputStream error,
-                           final long timeoutDuration )
+                           final long timeoutDuration,
+                           final boolean shutdownStreams )
     {
         if( null == process )
         {
@@ -100,6 +122,7 @@ class ProcessMonitor
         m_output = output;
         m_error = error;
         m_timeout = timeout;
+        m_shutdownStreams = shutdownStreams;
     }
 
     /**
@@ -139,9 +162,20 @@ class ProcessMonitor
         //that we have got all the data
         processStreams();
 
-        IOUtil.shutdownStream( m_input );
-        IOUtil.shutdownStream( m_output );
-        IOUtil.shutdownStream( m_error );
+        cleanupStreams();
+    }
+
+    /**
+     * Utility method which cleans up all IO Streams, if required.
+     */
+    private void cleanupStreams()
+    {
+        if( m_shutdownStreams )
+        {
+            IOUtil.shutdownStream( m_input );
+            IOUtil.shutdownStream( m_output );
+            IOUtil.shutdownStream( m_error );
+        }
     }
 
     /**