WIP - move Cyc-current-exception-handler to runtime

cgen.scm

@@ -415,6 +415,7 @@
      ((eq? p '%halt)                 "__halt")
      ((eq? p 'exit)                  "__halt")
      ((eq? p 'Cyc-default-exception-handler)  "Cyc_default_exception_handler")
+     ((eq? p 'Cyc-current-exception-handler)  "Cyc_current_exception_handler")
      ((eq? p 'current-input-port)    "Cyc_io_current_input_port")
      ((eq? p 'open-input-file)       "Cyc_io_open_input_file")
      ((eq? p 'close-input-port)      "Cyc_io_close_input_port")

eval.scm

@@ -189,6 +189,8 @@
       (list 'Cyc-set-cvar! Cyc-set-cvar!)
       (list 'Cyc-cvar? Cyc-cvar?)
       (list 'Cyc-has-cycle? Cyc-has-cycle?)
+      (list 'Cyc-default-exception-handler Cyc-default-exception-handler)
+      (list 'Cyc-current-exception-handler Cyc-current-exception-handler)
       (list '+ +)
       (list '- -)
       (list '* *)

runtime.h

@@ -198,6 +198,14 @@ static object Cyc_default_exception_handler(int argc, closure _, object err) {
     printf("\n");
     exit(1);
     return nil;
+
+// TODO: need to avoid using a global here, or add a define to shadow it for libcyclone
+object Cyc_current_exception_handler() {
+  if (nil(__glo__85exception_91handler_91stack_85)) {
+    return primitive_Cyc_91default_91exception_91handler;
+  } else {
+    return __glo__85exception_91handler_91stack_85;
+  }
 }
 
 /* Provide the ability to raise an exception from the C runtime. 
@@ -1108,6 +1116,8 @@ static void _string_91_125number(object cont, object args) {
 //static void _error(object cont, object args) {
 //    integer_type argc = Cyc_length(args);
 //    dispatch_va(argc.value, dispatch_error, cont, cont, args); }
+static void _Cyc_91current_91exception_91handler(object cont, object args) {
+    return_funcall1(cont, Cyc_current_exception_handler()); }
 static void _Cyc_91default_91exception_91handler(object cont, object args) {
     // TODO: this is a quick-and-dirty implementation, may be a better way to write this
     Cyc_default_exception_handler(1, args, car(args));
@@ -1172,6 +1182,10 @@ defprimitive(apply, apply, &_apply); /* apply */
 defprimitive(_75halt, %halt, &__75halt); /* %halt */
 defprimitive(exit, exit, &_cyc_exit); /* exit */
 //defprimitive(error, error, &_error); /* error */
+defprimitive(
+    Cyc_91current_91exception_91handler,
+    Cyc_current_exception_handler,
+    &_Cyc_91current_91exception_91handler); /* Cyc-current-exception-handler */
 defprimitive(
     Cyc_91default_91exception_91handler,
     Cyc_default_exception_handler,

trans.scm

@@ -214,10 +214,10 @@
   (define (Cyc-remove-exception-handler)
      (if (not (null? *exception-handler-stack*))
         (set! *exception-handler-stack* (cdr *exception-handler-stack*))))
-  (define (Cyc-current-exception-handler)
+;  (define (Cyc-current-exception-handler)
-    (if (null? *exception-handler-stack*)
+;    (if (null? *exception-handler-stack*)
-      Cyc-default-exception-handler
+;      Cyc-default-exception-handler
-      (car *exception-handler-stack*)))
+;      (car *exception-handler-stack*)))
 ))
 
 ;; Built-in macros
@@ -699,6 +699,7 @@
      %halt
      exit
      Cyc-default-exception-handler
+     Cyc-current-exception-handler
      cons
      cell-get
      set-global!
@@ -766,6 +767,7 @@
                   %halt
                   exit
                   Cyc-default-exception-handler
+                  Cyc-current-exception-handler
                   cell-get
                   set-global!
                   set-cell!