Merged mblock work-in-progress eb/mb -r4798:4808 into trunk.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@4809 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 50 insertions, 0 deletions

diff --git a/mblock/src/lib/mb_runtime_placeholder.h b/mblock/src/lib/mb_runtime_placeholder.h
new file mode 100644
index 000000000..b55d39f94
--- /dev/null
+++ b/mblock/src/lib/mb_runtime_placeholder.h
@@ -0,0 +1,50 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio 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 General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifndef INCLUDED_MB_RUNTIME_PLACEHOLDER_H
+#define INCLUDED_MB_RUNTIME_PLACEHOLDER_H
+
+#include <mb_runtime.h>
+
+/*!
+ * \brief Concrete runtime that serves as a placeholder until the real
+ * runtime is known.
+ *
+ * The singleton instance of this class is installed in the d_runtime
+ * instance variable of each mb_mblock_impl at construction time.
+ * Having a valid instance of runtime removes the "pre runtime::run"
+ * corner case, and allows us to lock and unlock the big runtime lock
+ * even though there's no "real runtime" yet.
+ */
+class mb_runtime_placeholder : public mb_runtime
+{
+
+public:
+  mb_runtime_placeholder();
+  ~mb_runtime_placeholder();
+
+  //! throws mbe_not_implemented
+  bool run(mb_mblock_sptr top);
+
+  //! Return the placeholder singleton
+  static mb_runtime *singleton();
+};
+
+#endif /* INCLUDED_MB_RUNTIME_PLACEHOLDER_H */