fix dtags.eftar file descriptor leak

fixes #535

Author: Jens Elkner

src/org/opensolaris/opengrok/web/PageConfig.java

@@ -44,6 +44,7 @@
 import java.util.regex.Pattern;
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.ServletRequest;
 import org.apache.commons.jrcs.diff.Diff;
 import org.apache.commons.jrcs.diff.DifferentiationFailedException;
 import org.opensolaris.opengrok.analysis.AnalyzerGuru;
@@ -58,10 +59,10 @@
 import org.opensolaris.opengrok.util.IOUtils;
 
 /**
- * A simple container to lazy initialize common vars wrt. a single request. It
- * MUST NOT be shared between several requests and {@link #cleanup()} should be
- * called before the page context gets destroyed (e.g. by overwriting
- * {@code jspDestroy()} or when leaving the {@code service} method. <p> Purpose
+ * A simple container to lazy initialize common vars wrt. a single request.
+ * It MUST NOT be shared between several requests and
+ * {@link #cleanup(ServletRequest)} should be called before the page context 
+ * gets destroyed (e.g.when leaving the {@code service} method). <p> Purpose
  * is to decouple implementation details from web design, so that the JSP
  * developer does not need to know every implementation detail and normally has
  * to deal with this class/wrapper, only (so some people may like to call this
@@ -1202,6 +1203,7 @@ public static PageConfig get(HttpServletRequest request) {
         request.setAttribute(ATTR_NAME, pcfg);
         return pcfg;
     }
+    
     private static final String ATTR_NAME = PageConfig.class.getCanonicalName();
     private HttpServletRequest req;
 
@@ -1210,17 +1212,24 @@ private PageConfig(HttpServletRequest req) {
     }
 
     /**
-     * Cleanup all allocated resources. Should always be called right before
-     * leaving the _jspService / service.
+     * Cleanup all allocated resources (if any) from the instance attached to 
+     * the given request.
+     * @param sr request to check, cleanup. Ignored if {@code null}.
+     * @see PageConfig#get(HttpServletRequest)
+     * 
      */
-    public void cleanup() {
-        if (req != null) {
-            req.removeAttribute(ATTR_NAME);
-            req = null;
+    public static void cleanup(ServletRequest sr) {
+        if (sr == null) {
+            return;
         }
-        env = null;
-        if (eftarReader != null) {
-            eftarReader.close();
+        PageConfig cfg = (PageConfig) sr.getAttribute(ATTR_NAME);
+        if (cfg == null) {
+            return;
+        }        
+        sr.removeAttribute(ATTR_NAME);
+        cfg.env = null;
+        if (cfg.eftarReader != null) {
+            cfg.eftarReader.close();
         }
     }
 }

src/org/opensolaris/opengrok/web/WebappListener.java

@@ -32,6 +32,8 @@
 import javax.servlet.ServletContext;
 import javax.servlet.ServletContextEvent;
 import javax.servlet.ServletContextListener;
+import javax.servlet.ServletRequestEvent;
+import javax.servlet.ServletRequestListener;
 import org.opensolaris.opengrok.OpenGrokLogger;
 import org.opensolaris.opengrok.configuration.RuntimeEnvironment;
 
@@ -40,7 +42,8 @@
  *
  * @author Trond Norbye
  */
-public final class WebappListener implements ServletContextListener {
+public final class WebappListener
+    implements ServletContextListener, ServletRequestListener {
 
     @Override
     public void contextInitialized(final ServletContextEvent servletContextEvent) {
@@ -86,4 +89,20 @@ public void contextInitialized(final ServletContextEvent servletContextEvent) {
     public void contextDestroyed(final ServletContextEvent servletContextEvent) {
         RuntimeEnvironment.getInstance().stopConfigurationListenerThread();
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void requestDestroyed(ServletRequestEvent e) {
+        PageConfig.cleanup(e.getServletRequest());
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void requestInitialized(ServletRequestEvent e) {
+        // pass through
+    }
 }

web/pageconfig.jspf

@@ -26,11 +26,4 @@ Portions Copyright 2011 Jens Elkner.
 org.opensolaris.opengrok.web.PageConfig"
 %><%!
     private PageConfig cfg;
-    /** Just cleanup cached objects */
-
-    public void jspDestroy() {
-        if (cfg != null) {
-            cfg.cleanup();
-        }
-    }
 %>