Implement invocation interface; don't create new thread for main.

From-SVN: r42428

libjava/java/lang/Thread.java

@@ -1,6 +1,6 @@
 // Thread.java - Thread class.
 
-/* Copyright (C) 1998, 1999, 2000  Free Software Foundation
+/* Copyright (C) 1998, 1999, 2000, 2001  Free Software Foundation
 
    This file is part of libgcj.
 
@@ -209,18 +209,20 @@ public class Thread implements Runnable
 
   private final native void initialize_native ();
 
-  private final synchronized static String gen_name ()
-  {
-    String n;
-    n = "Thread-" + nextThreadNumber;
-    ++nextThreadNumber;
-    return n;
-  }
+  private final native static String gen_name ();
 
   public Thread (ThreadGroup g, Runnable r, String n)
   {
-    Thread current = currentThread ();
-          
+    this (currentThread (), g, r, n);
+
+    // The Class Libraries book says ``threadName cannot be null''.  I
+    // take this to mean NullPointerException.
+    if (n == null)
+      throw new NullPointerException ();
+  }
+
+  private Thread (Thread current, ThreadGroup g, Runnable r, String n)
+  {
     if (g == null)
       {
 	// If CURRENT is null, then we are bootstrapping the first thread. 
@@ -233,17 +235,6 @@ public class Thread implements Runnable
     else
       group = g;
       
-    group.checkAccess();
-
-    // The Class Libraries book says ``threadName cannot be null''.  I
-    // take this to mean NullPointerException.
-    if (n == null)
-      throw new NullPointerException ();
-
-    name = n;
-    group.addThread(this);
-    runnable = r;
-
     data = null;
     interrupt_flag = false;
     alive_flag = false;
@@ -251,6 +242,8 @@ public class Thread implements Runnable
 
     if (current != null)
       {
+	group.checkAccess();
+
 	daemon_flag = current.isDaemon();
         int gmax = group.getMaxPriority();
 	int pri = current.getPriority();
@@ -263,6 +256,10 @@ public class Thread implements Runnable
 	priority = NORM_PRIORITY;
       }
 
+    name = n;
+    group.addThread(this);
+    runnable = r;
+
     initialize_native ();
   }
 
@@ -315,9 +312,6 @@ public class Thread implements Runnable
   private boolean startable_flag;
   private ClassLoader context_class_loader;
 
-  // Our native data.
+  // Our native data - points to an instance of struct natThread.
   private Object data;
-
-  // Next thread number to assign.
-  private static int nextThreadNumber = 0;
 }

libjava/java/lang/natThread.cc

@@ -1,6 +1,6 @@
 // natThread.cc - Native part of Thread class.
 
-/* Copyright (C) 1998, 1999, 2000  Free Software Foundation
+/* Copyright (C) 1998, 1999, 2000, 2001  Free Software Foundation
 
    This file is part of libgcj.
 
@@ -59,7 +59,7 @@ java::lang::Thread::initialize_native (void)
 {
   natThread *nt = (natThread *) _Jv_AllocBytes (sizeof (natThread));
   
-  // The native thread data is kept in a Object field, not a rawdata, so that
+  // The native thread data is kept in a Object field, not a RawData, so that
   // the GC allocator can be used and a finalizer run after the thread becomes
   // unreachable. Note that this relies on the GC's ability to finalize 
   // non-Java objects. FIXME?
@@ -322,6 +322,34 @@ java::lang::Thread::suspend (void)
     (JvNewStringLatin1 ("java::lang::Thread::suspend unimplemented"));
 }
 
+static int nextThreadNumber = 0;
+
+jstring
+java::lang::Thread::gen_name (void)
+{
+  jint i;
+  jclass sync = &java::lang::Thread::class$;
+  {
+    JvSynchronize dummy(sync); 
+    i = ++nextThreadNumber;
+  }
+
+  // Use an array large enough for "-2147483648"; i.e. 11 chars, + "Thread-".
+  jchar buffer[7+11];
+  jchar *bufend = (jchar *) ((char *) buffer + sizeof(buffer));
+  i = _Jv_FormatInt (bufend, i);
+  jchar *ptr = bufend - i;
+  // Prepend "Thread-".
+  *--ptr = '-';
+  *--ptr = 'd';
+  *--ptr = 'a';
+  *--ptr = 'e';
+  *--ptr = 'r';
+  *--ptr = 'h';
+  *--ptr = 'T';
+  return JvNewString (ptr, bufend - ptr);
+}
+
 void
 java::lang::Thread::yield (void)
 {
@@ -344,3 +372,33 @@ _Jv_SetCurrentJNIEnv (JNIEnv *env)
   JvAssert (t != NULL);
   ((natThread *) t->data)->jni_env = env;
 }
+
+java::lang::Thread*
+_Jv_AttachCurrentThread(jstring name, java::lang::ThreadGroup* group)
+{
+  java::lang::Thread *thread = _Jv_ThreadCurrent ();
+  if (thread != NULL)
+    return thread;
+  if (name == NULL)
+    name = java::lang::Thread::gen_name ();
+  thread = new java::lang::Thread (NULL, group, NULL, name);
+  thread->startable_flag = false;
+  thread->alive_flag = true;
+  natThread *nt = (natThread *) thread->data;
+  _Jv_ThreadRegister (nt->thread);
+  return thread;
+}
+
+jint
+_Jv_DetachCurrentThread (void)
+{
+  java::lang::Thread *t = _Jv_ThreadCurrent ();
+  if (t == NULL)
+    return -1;
+
+  _Jv_ThreadUnRegister ();
+  // Release the monitors.
+  t->finish_ ();
+
+  return 0;
+}