1 files changed, 125 insertions, 0 deletions
diff --git a/gnuradio-runtime/lib/vmcircbuf.h b/gnuradio-runtime/lib/vmcircbuf.h
new file mode 100644
index 0000000000..c3ddfe0043
--- /dev/null
+++ b/gnuradio-runtime/lib/vmcircbuf.h
@@ -0,0 +1,125 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2003,2013 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 3, 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 GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef GR_VMCIRCBUF_H
+#define GR_VMCIRCBUF_H
+
+#include <gnuradio/api.h>
+#include <vector>
+
+namespace gr {
+
+  /*!
+   * \brief abstract class to implement doubly mapped virtual memory circular buffers
+   * \ingroup internal
+   */
+  class GR_RUNTIME_API vmcircbuf
+  {
+  protected:
+    int d_size;
+    char *d_base;
+
+    // CREATORS
+    vmcircbuf(int size) : d_size(size), d_base(0) {};
+
+  public:
+    virtual ~vmcircbuf();
+
+    // ACCESSORS
+    void *pointer_to_first_copy()  const{ return d_base; }
+    void *pointer_to_second_copy() const{ return d_base + d_size; }
+  };
+
+  /*!
+   * \brief abstract factory for creating circular buffers
+   */
+  class GR_RUNTIME_API vmcircbuf_factory
+  {
+  protected:
+    vmcircbuf_factory() {};
+    virtual ~vmcircbuf_factory();
+
+  public:
+
+    /*!
+     * \brief return name of this factory
+     */
+    virtual const char *name() const = 0;
+
+    /*!
+     * \brief return granularity of mapping, typically equal to page size
+     */
+    virtual int granularity() = 0;
+
+    /*!
+     * \brief return a gr::vmcircbuf, or 0 if unable.
+     *
+     * Call this to create a doubly mapped circular buffer.
+     */
+    virtual vmcircbuf *make(int size) = 0;
+  };
+
+  /*
+   * \brief pulls together all implementations of gr::vmcircbuf
+   */
+  class GR_RUNTIME_API vmcircbuf_sysconfig
+  {
+  public:
+    /*
+     * \brief return the single instance of the default factory.
+     *
+     * returns the default factory to use if it's already defined,
+     * else find the first working factory and use it.
+     */
+    static vmcircbuf_factory *get_default_factory();
+
+    static int granularity()         { return get_default_factory()->granularity(); }
+    static vmcircbuf *make(int size) { return get_default_factory()->make(size);    }
+
+    // N.B. not all factories are guaranteed to work.
+    // It's too hard to check everything at config time, so we check at runtime
+    static std::vector<vmcircbuf_factory*> all_factories();
+
+    // make this factory the default
+    static void set_default_factory(vmcircbuf_factory *f);
+
+    /*!
+     * \brief  Does this factory really work?
+     *
+     * verbose = 0: silent
+     * verbose = 1: names of factories tested and results
+     * verbose = 2: all intermediate results
+     */
+    static bool test_factory(vmcircbuf_factory *f, int verbose);
+
+    /*!
+     * \brief Test all factories, return true if at least one of them works
+     * verbose = 0: silent
+     * verbose = 1: names of factories tested and results
+     * verbose = 2: all intermediate results
+     */
+    static bool test_all_factories(int verbose);
+  };
+
+} /* namespace gr */
+
+#endif /* GR_VMCIRCBUF_H */