fix time==0 case in Unsafe.park and implement JVM_DumpThreads

Also, set name field on system threads for OpenJDK build to avoid NPEs
in Thread.getName.

src/classpath-openjdk.cpp

@@ -313,6 +313,8 @@ class MyClasspath : public Classpath {
       setObjectClass(t, group, type(t, Machine::ThreadGroupType));
       threadGroupMaxPriority(t, group) = MaxPriority;
     }
+
+    PROTECT(t, group);
     
     object thread = allocate(t, FixedSizeOfThread, true);
     setObjectClass(t, thread, type(t, Machine::ThreadType));
@@ -320,6 +322,17 @@ class MyClasspath : public Classpath {
     threadGroup(t, thread) = group;
     threadContextClassLoader(t, thread) = root(t, Machine::BootLoader);
 
+    PROTECT(t, thread);
+
+    const unsigned BufferSize = 256;
+    char buffer[BufferSize];
+    unsigned length = vm::snprintf(buffer, BufferSize, "Thread-%p", thread);
+    object name = makeCharArray(t, length);
+    for (unsigned i = 0; i < length; ++i) {
+      charArrayBody(t, name, i) = buffer[i];
+    }
+    set(t, thread, ThreadName, name);
+
     return thread;
   }
 
@@ -1708,10 +1721,9 @@ Avian_sun_misc_Unsafe_park
   
   if (absolute) {
     time -= t->m->system->now();
-  }
+    if (time <= 0) {
-
+      return;
-  if (time <= 0) {
+    }
-    return;
   }
 
   monitorAcquire(t, local::interruptLock(t, t->javaThread));
@@ -2162,7 +2174,44 @@ extern "C" JNIEXPORT jobjectArray JNICALL
 EXPORT(JVM_GetAllThreads)(Thread*, jclass) { abort(); }
 
 extern "C" JNIEXPORT jobjectArray JNICALL
-EXPORT(JVM_DumpThreads)(Thread*, jclass, jobjectArray) { abort(); }
+EXPORT(JVM_DumpThreads)(Thread* t, jclass, jobjectArray threads)
+{
+  ENTER(t, Thread::ActiveState);
+
+  unsigned threadsLength = objectArrayLength(t, *threads);
+  object arrayClass = resolveObjectArrayClass
+    (t, classLoader(t, type(t, Machine::StackTraceElementType)),
+     type(t, Machine::StackTraceElementType));
+  object result = makeObjectArray(t, arrayClass, threadsLength);
+  PROTECT(t, result);
+
+  for (unsigned threadsIndex = 0; threadsIndex < threadsLength;
+       ++ threadsIndex)
+  {
+    Thread* peer = reinterpret_cast<Thread*>
+      (threadPeer(t, objectArrayBody(t, *threads, threadsIndex)));
+
+    if (peer) {
+      object trace = t->m->processor->getStackTrace(t, peer);
+      PROTECT(t, trace);
+
+      unsigned traceLength = objectArrayLength(t, trace);
+      object array = makeObjectArray
+        (t, type(t, Machine::StackTraceElementType), traceLength);
+      PROTECT(t, array);
+
+      for (unsigned traceIndex = 0; traceIndex < traceLength; ++ traceIndex) {
+        object ste = makeStackTraceElement
+          (t, objectArrayBody(t, trace, traceIndex));
+        set(t, array, ArrayBody + (traceIndex * BytesPerWord), ste);
+      }
+
+      set(t, result, ArrayBody + (threadsIndex * BytesPerWord), array);
+    }
+  }
+
+  return makeLocalReference(t, result);
+}
 
 extern "C" JNIEXPORT jclass JNICALL
 EXPORT(JVM_CurrentLoadedClass)(Thread*) { abort(); }

src/machine.cpp

@@ -1837,48 +1837,6 @@ resolveArrayClass(Thread* t, object loader, object spec, bool throw_)
   }
 }
 
-object
-resolveObjectArrayClass(Thread* t, object loader, object elementClass)
-{
-  { object arrayClass = classRuntimeDataArrayClass
-      (t, getClassRuntimeData(t, elementClass));
-    if (arrayClass) {
-      return arrayClass;
-    }
-  }
-
-  PROTECT(t, loader);
-  PROTECT(t, elementClass);
-
-  object elementSpec = className(t, elementClass);
-  PROTECT(t, elementSpec);
-
-  object spec;
-  if (byteArrayBody(t, elementSpec, 0) == '[') {
-    spec = makeByteArray(t, byteArrayLength(t, elementSpec) + 1);
-    byteArrayBody(t, spec, 0) = '[';
-    memcpy(&byteArrayBody(t, spec, 1),
-           &byteArrayBody(t, elementSpec, 0),
-           byteArrayLength(t, elementSpec));
-  } else {
-    spec = makeByteArray(t, byteArrayLength(t, elementSpec) + 3);
-    byteArrayBody(t, spec, 0) = '[';
-    byteArrayBody(t, spec, 1) = 'L';
-    memcpy(&byteArrayBody(t, spec, 2),
-           &byteArrayBody(t, elementSpec, 0),
-           byteArrayLength(t, elementSpec) - 1);
-    byteArrayBody(t, spec, byteArrayLength(t, elementSpec) + 1) = ';';
-    byteArrayBody(t, spec, byteArrayLength(t, elementSpec) + 2) = 0;
-  }
-
-  object arrayClass = resolveClass(t, loader, spec);
-
-  set(t, getClassRuntimeData(t, elementClass), ClassRuntimeDataArrayClass,
-      arrayClass);
-
-  return arrayClass;
-}
-
 void
 removeMonitor(Thread* t, object o)
 {
@@ -3519,6 +3477,48 @@ initClass(Thread* t, object c)
   }
 }
 
+object
+resolveObjectArrayClass(Thread* t, object loader, object elementClass)
+{
+  { object arrayClass = classRuntimeDataArrayClass
+      (t, getClassRuntimeData(t, elementClass));
+    if (arrayClass) {
+      return arrayClass;
+    }
+  }
+
+  PROTECT(t, loader);
+  PROTECT(t, elementClass);
+
+  object elementSpec = className(t, elementClass);
+  PROTECT(t, elementSpec);
+
+  object spec;
+  if (byteArrayBody(t, elementSpec, 0) == '[') {
+    spec = makeByteArray(t, byteArrayLength(t, elementSpec) + 1);
+    byteArrayBody(t, spec, 0) = '[';
+    memcpy(&byteArrayBody(t, spec, 1),
+           &byteArrayBody(t, elementSpec, 0),
+           byteArrayLength(t, elementSpec));
+  } else {
+    spec = makeByteArray(t, byteArrayLength(t, elementSpec) + 3);
+    byteArrayBody(t, spec, 0) = '[';
+    byteArrayBody(t, spec, 1) = 'L';
+    memcpy(&byteArrayBody(t, spec, 2),
+           &byteArrayBody(t, elementSpec, 0),
+           byteArrayLength(t, elementSpec) - 1);
+    byteArrayBody(t, spec, byteArrayLength(t, elementSpec) + 1) = ';';
+    byteArrayBody(t, spec, byteArrayLength(t, elementSpec) + 2) = 0;
+  }
+
+  object arrayClass = resolveClass(t, loader, spec);
+
+  set(t, getClassRuntimeData(t, elementClass), ClassRuntimeDataArrayClass,
+      arrayClass);
+
+  return arrayClass;
+}
+
 object
 makeObjectArray(Thread* t, object elementClass, unsigned count)
 {

src/machine.h

@@ -2196,6 +2196,9 @@ postInitClass(Thread* t, object c);
 void
 initClass(Thread* t, object c);
 
+object
+resolveObjectArrayClass(Thread* t, object loader, object elementClass);
+
 object
 makeObjectArray(Thread* t, object elementClass, unsigned count);