Re: invoke_method calling private methods when invoked on integers

Hi,

At Wed, 7 Nov 2007 05:44:17 +0900,
David Flanagan wrote in [ruby-core:13245]:
> The rdoc comment for invoke_method includes this example:
> 
>   *     1.invoke_method(:puts, "hello")  # causes NoMethodError
> 
> In fact, however, the current implementation does allows private methods 
> to be invoked if the receiver is any fixnum, symbol, true, false, or nil.

> The patch isn't perfect, as it still treats a receiver of nil as the 
> same as having no receiver at all.

It needs to access VM flags, I guess.


Index: eval.c
===================================================================
--- eval.c	(revision 13827)
+++ eval.c	(working copy)
@@ -1508,9 +1508,9 @@ VALUE
 rb_invoke_method(int argc, VALUE *argv, VALUE recv)
 {
+    int rb_vm_cfunc_funcall_p(rb_control_frame_t *);
     int scope = NOEX_PUBLIC;
     rb_thread_t *th = GET_THREAD();
-    rb_control_frame_t *cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(th->cfp);
 
-    if (SPECIAL_CONST_P(cfp->sp[0])) {
+    if (rb_vm_cfunc_funcall_p(th->cfp)) {
 	scope = NOEX_NOSUPER | NOEX_PRIVATE;
     }
Index: insnhelper.ci
===================================================================
--- insnhelper.ci	(revision 13827)
+++ insnhelper.ci	(working copy)
@@ -49,5 +49,5 @@ vm_push_frame(rb_thread_t *th, rb_iseq_t
     cfp->bp = sp + 1;
     cfp->iseq = iseq;
-    cfp->flag = VM_FRAME_FLAG(type);
+    cfp->flag = type;
     cfp->self = self;
     cfp->lfp = lfp;
@@ -348,5 +348,6 @@ call_cfunc(VALUE (*func)(), VALUE recv, 
 static inline VALUE
 vm_call_cfunc(rb_thread_t *th, rb_control_frame_t *reg_cfp, int num,
-	      ID id, VALUE recv, VALUE klass, NODE *mn, rb_block_t *blockptr)
+	      ID id, VALUE recv, VALUE klass, VALUE flag,
+	      NODE *mn, rb_block_t *blockptr)
 {
     VALUE val;
@@ -355,6 +356,6 @@ vm_call_cfunc(rb_thread_t *th, rb_contro
     {
 	rb_control_frame_t *cfp =
-	  vm_push_frame(th, 0, FRAME_MAGIC_CFUNC,
-			recv, (VALUE) blockptr, 0, reg_cfp->sp, 0, 1);
+	    vm_push_frame(th, 0, FRAME_MAGIC_CFUNC | flag * (FRAME_MAGIC_MASK + 1),
+			  recv, (VALUE) blockptr, 0, reg_cfp->sp, 0, 1);
 
 	cfp->method_id = id;
@@ -375,4 +376,12 @@ vm_call_cfunc(rb_thread_t *th, rb_contro
 }
 
+static int
+vm_cfunc_flags(rb_control_frame_t *cfp)
+{
+    if (RUBYVM_CFUNC_FRAME_P(cfp))
+	return cfp->flag / (FRAME_MAGIC_MASK + 1);
+    return 0;
+}
+
 static inline VALUE
 vm_call_bmethod(rb_thread_t *th, ID id, VALUE procval, VALUE recv,
@@ -488,5 +497,5 @@ vm_call_method(rb_thread_t *th, rb_contr
 	      }
 	      case NODE_CFUNC:{
-		  val = vm_call_cfunc(th, cfp, num, id, recv, klass, node, blockptr);
+		  val = vm_call_cfunc(th, cfp, num, id, recv, klass, flag, node, blockptr);
 		  break;
 	      }
Index: vm.c
===================================================================
--- vm.c	(revision 13827)
+++ vm.c	(working copy)
@@ -1437,4 +1437,12 @@ rb_vm_call_cfunc(VALUE recv, VALUE (*fun
 }
 
+int
+rb_vm_cfunc_funcall_p(rb_control_frame_t *cfp)
+{
+    if (vm_cfunc_flags(cfp) & (VM_CALL_FCALL_BIT | VM_CALL_VCALL_BIT))
+	return Qtrue;
+    return Qfalse;
+}
+
 /* vm */
 


-- 
Nobu Nakada