If a project is not set for concurrent builds and there is more than one job

in the queue (e.g. if the build is parameterized), then don't make more than
one of them runnable.


git-svn-id: https://hudson.dev.java.net/svn/hudson/trunk/hudson/main@21365 71c3de6d-444a-0410-be80-ed276b4c234a

core/src/main/java/hudson/model/Queue.java

@@ -29,6 +29,7 @@ import hudson.ExtensionPoint;
 import hudson.Util;
 import hudson.XmlFile;
 import hudson.remoting.AsyncFutureImpl;
+import hudson.model.AbstractProject;
 import hudson.model.Node.Mode;
 import hudson.model.ParametersAction;
 import hudson.triggers.SafeTimerTask;
@@ -864,6 +865,14 @@ public class Queue extends ResourceController implements Saveable {
         while (itr.hasNext()) {
             BlockedItem p = itr.next();
             if (!isBuildBlocked(p.task)) {
+                // Make sure that we don't make more than one item buildable unless the
+                // project can handle concurrent builds
+                if (p.task instanceof AbstractProject<?,?>) {
+                    AbstractProject<?,?> proj = (AbstractProject<?,?>) p.task;
+                    if (!proj.isConcurrentBuild() && buildables.containsKey(p.task)) {
+                        continue;
+                    }
+                }
                 // ready to be executed
                 LOGGER.fine(p.task.getFullDisplayName() + " no longer blocked");
                 itr.remove();