Added stepping to debugger

scmvm/debugger.scm

@@ -12,15 +12,16 @@
             debugger-breakpoint-add! debugger-breakpoint-ref
             debugger-breakpoint-enable! debugger-breakpoint-disable!
             debugger-breakpoint-delete!
-            debugger-continue))
+            debugger-step debugger-continue))
 
 (define-record-type <debugger>
-  (make-debugger vm source breakpoints continuation)
+  (make-debugger vm source breakpoints continuation stepping)
   debugger?
   (vm debugger-vm)
   (source debugger-source)
   (breakpoints debugger-breakpoints)
-  (continuation debugger-continuation debugger-continuation-set!))
+  (continuation debugger-continuation debugger-continuation-set!)
+  (stepping debugger-stepping? debugger-stepping-set!))
 
 (define (make-breakpoints labels)
   (define the-breakpoints '())
@@ -51,17 +52,23 @@
   (define the-debugger #f)
   (define (debug)
     (shift k
-      (if (((debugger-breakpoints the-debugger) 'ref) (vm-pc (debugger-vm the-debugger)))
-          (debugger-continuation-set! the-debugger k)
-          (k))))
+     (if (or (debugger-stepping? the-debugger)
+             (((debugger-breakpoints the-debugger) 'ref) (vm-pc (debugger-vm the-debugger))))
+         (debugger-continuation-set! the-debugger k)
+         (k))))
   (define vm (make-vm #:debugger debug))
   (vm-load-program! vm prgm)
-  (set! the-debugger (make-debugger vm source (make-breakpoints symbols) #f))
+  (set! the-debugger (make-debugger vm source (make-breakpoints symbols) #f #f))
   (debugger-breakpoint-add! the-debugger 1)
   (reset (run-vm vm))
   the-debugger)
 
 (define (debugger-continue debugger)
+  (debugger-stepping-set! debugger #f)
+  ((debugger-continuation debugger)))
+
+(define (debugger-step debugger)
+  (debugger-stepping-set! debugger #t)
   ((debugger-continuation debugger)))
 
 (define (debugger-breakpoint-add! debugger breakpoint)