add @control and @prompt stub primitives

* libguile/Makefile.am:
* libguile/control.c:
* libguile/control.h:
* libguile/init.c: Add stub @control and @prompt primitives, for use
  when bootstrapping (ice-9 control).

libguile/control.c

@@ -0,0 +1,72 @@
+/* Copyright (C) 2010  Free Software Foundation, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#if HAVE_CONFIG_H
+#  include <config.h>
+#endif
+
+#include "libguile/_scm.h"
+#include "libguile/control.h"
+
+
+
+SCM scm_atcontrol (SCM, SCM, SCM);
+SCM_DEFINE (scm_atcontrol, "@control", 3, 0, 0,
+            (SCM tag, SCM type, SCM args),
+            "Transfer control to the handler of a delimited continuation.")
+#define FUNC_NAME s_scm_atcontrol
+{
+  abort ();
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+SCM scm_atprompt (SCM, SCM, SCM, SCM);
+SCM_DEFINE (scm_atprompt, "@prompt", 4, 0, 0,
+            (SCM tag, SCM thunk, SCM handler, SCM pre_unwind_handler),
+            "Begin a delimited continuation.")
+#define FUNC_NAME s_scm_atprompt
+{
+  abort ();
+  return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+
+static void
+scm_init_control (void)
+{
+#ifndef SCM_MAGIC_SNARFER
+#include "libguile/control.x"
+#endif
+}
+
+void
+scm_register_control (void)
+{
+  scm_c_register_extension ("libguile", "scm_init_control",
+                            (scm_t_extension_init_func)scm_init_control,
+                            NULL);
+}
+
+/*
+  Local Variables:
+  c-file-style: "gnu"
+  End:
+*/