thread kind and flag handling

* 256 states are enough for anyone (else fix the source)
 * add proper masking and handling of flags

src/backend/threadpool.c

@@ -179,6 +179,7 @@ lumiera_threadpool_release_thread(LumieraThread thread)
 {
   TRACE (threadpool);
   REQUIRE (thread, "invalid thread given");
+  thread->kind = thread->kind&0xff;
   REQUIRE (thread->kind < LUMIERA_THREADCLASS_COUNT, "thread belongs to an unknown pool kind: %d", thread->kind);
 
   REQUIRE (thread->state != LUMIERA_THREADSTATE_IDLE, "trying to park an already idle thread");

src/backend/threads.c

@@ -126,7 +126,7 @@ thread_loop (void* thread)
 // when this is called it should have already been decided that the function
 // shall run in parallel, as a thread
 LumieraThread
-lumiera_thread_run (enum lumiera_thread_class kind,
+lumiera_thread_run (int kind,
                     void (*function)(void *),
                     void * arg,
                     const char* purpose,
@@ -136,12 +136,12 @@ lumiera_thread_run (enum lumiera_thread_class kind,
   //  REQUIRE (function, "invalid function");
 
   // ask the threadpool for a thread (it might create a new one)
-  LumieraThread self = lumiera_threadpool_acquire_thread (kind, purpose, flag);
+  LumieraThread self = lumiera_threadpool_acquire_thread (kind&0xff, purpose, flag);
 
   // set the function and data to be run
   self->function = function;
   self->arguments = arg;
-
+  self->kind = kind;
   self->deadline.tv_sec = 0;
 
   // and let it really run (signal the condition var, the thread waits on it)

src/backend/threads.h

@@ -73,7 +73,7 @@ enum lumiera_thread_class
     LUMIERA_THREAD_CLASSES
     /** this just denotes the number of classes listed above,
         it is used to create arrays **/
-    LUMIERA_THREADCLASS_COUNT,
+    LUMIERA_THREADCLASS_COUNT,  /* must be <= 256, thats easy or? */
 
     // .. various thread flags follow
     /**
@@ -83,12 +83,12 @@ enum lumiera_thread_class
      *  The Thread must be very careful with locking, better don't.
      *  TODO explain syncronization issues
      **/
-    LUMIERA_THREAD_OR_NOT = 1<<16,
+    LUMIERA_THREAD_OR_NOT = 1<<8,
 
     /**
      * Thread must be joined finally
      **/
-    LUMIERA_THREAD_JOINABLE = 1<<17
+    LUMIERA_THREAD_JOINABLE = 1<<9
   };
 
 #undef LUMIERA_THREAD_CLASS
@@ -195,7 +195,7 @@ lumiera_thread_delete (LumieraThread self);
  * @param flag NoBug flag used for logging the thread startup and return
  */
 LumieraThread
-lumiera_thread_run (enum lumiera_thread_class kind,
+lumiera_thread_run (int kind,
                     void (*function)(void *),
                     void * arg,
                     const char* purpose,