--- IO-AIO/AIO.xs	2008/09/25 07:56:07	1.126
+++ IO-AIO/AIO.xs	2008/09/30 14:07:59	1.128
@@ -82,6 +82,19 @@
 # define SvVAL64 SvNV
 #endif
 
+/*****************************************************************************/
+
+#if __GNUC__ >= 3
+# define expect(expr,value) __builtin_expect ((expr),(value))
+#else
+# define expect(expr,value) (expr)
+#endif
+
+#define expect_false(expr) expect ((expr) != 0, 0)
+#define expect_true(expr)  expect ((expr) != 0, 1)
+
+/*****************************************************************************/
+
 static HV *stash;
 typedef SV SV8; /* byte-sv, used for argument-checking */
 
@@ -183,7 +196,7 @@
 {
   eio_submit (req);
 
-  if (on_next_submit)
+  if (expect_false (on_next_submit))
     {
       dSP;
       SV *cb = sv_2mortal (on_next_submit);
@@ -203,7 +216,7 @@
   if (req->flags & FLAG_SV2_RO_OFF)
     SvREADONLY_off (req->sv2);
 
-  if (!EIO_CANCELLED (req) && SvOK (req->callback))
+  if (!EIO_CANCELLED (req) && req->callback)
     {
       ENTER;
       SAVETMPS;
@@ -450,19 +463,37 @@
   create_respipe ();
 }
 
+static SV *
+get_cb (SV *cb_sv)
+{
+  HV *st;
+  GV *gvp;
+  CV *cv;
+
+  if (!SvOK (cb_sv))
+    return 0;
+
+  cv = sv_2cv (cb_sv, &st, &gvp, 0);
+
+  if (!cv)
+    croak ("IO::AIO watcher callback must be undef or a CODE reference");
+
+  return (SV *)cv;
+}
+
 #define dREQ							\
+  SV *cb_cv;							\
   aio_req req;							\
   int req_pri = next_pri;					\
   next_pri = EIO_PRI_DEFAULT;					\
 								\
-  if (SvOK (callback) && !SvROK (callback))			\
-    croak ("callback must be undef or of reference type");	\
+  cb_cv = get_cb (callback);					\
 								\
   Newz (0, req, 1, eio_req);					\
   if (!req)							\
     croak ("out of memory during eio_req allocation");		\
 								\
-  req->callback = newSVsv (callback);				\
+  req->callback = SvREFCNT_inc (cb_cv);				\
   req->pri = req_pri
 
 #define REQ_SEND						\
@@ -898,7 +929,7 @@
 
         req->type = EIO_GROUP;
 
-        eio_submit (req);
+        req_submit (req);
         XPUSHs (req_sv (req, AIO_GRP_KLASS));
 }
 
@@ -1027,9 +1058,19 @@
 
 void
 cb (aio_req_ornot req, SV *callback=&PL_sv_undef)
-	CODE:
-        SvREFCNT_dec (req->callback);
-        req->callback = newSVsv (callback);
+	PPCODE:
+{
+        if (GIMME_V != G_VOID)
+          XPUSHs (req->callback ? sv_2mortal (newRV_inc (req->callback)) : &PL_sv_undef);
+
+        if (items > 1)
+          {
+            SV *cb_cv = get_cb (callback);
+
+            SvREFCNT_dec (req->callback);
+            req->callback = SvREFCNT_inc (cb_cv);
+          }
+}
 
 MODULE = IO::AIO                PACKAGE = IO::AIO::GRP