1 files changed, 92 insertions, 0 deletions
diff --git a/include/gnuradio/gr_msg_queue.h b/include/gnuradio/gr_msg_queue.h
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+++ b/include/gnuradio/gr_msg_queue.h
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+/* -*- c++ -*- */
+/*
+ * Copyright 2005,2009 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 INCLUDED_GR_MSG_QUEUE_H
+#define INCLUDED_GR_MSG_QUEUE_H
+
+#include <gr_core_api.h>
+#include <gr_msg_handler.h>
+#include <gruel/thread.h>
+
+class gr_msg_queue;
+typedef boost::shared_ptr<gr_msg_queue> gr_msg_queue_sptr;
+
+GR_CORE_API gr_msg_queue_sptr gr_make_msg_queue(unsigned int limit=0);
+
+/*!
+ * \brief thread-safe message queue
+ * \ingroup misc
+ */
+class GR_CORE_API gr_msg_queue : public gr_msg_handler {
+
+  gruel::mutex		    d_mutex;
+  gruel::condition_variable d_not_empty;
+  gruel::condition_variable d_not_full;
+  gr_message_sptr	    d_head;
+  gr_message_sptr	    d_tail;
+  unsigned int		    d_count;    // # of messages in queue.
+  unsigned int		    d_limit;    // max # of messages in queue.  0 -> unbounded
+
+public:
+  gr_msg_queue(unsigned int limit);
+  ~gr_msg_queue();
+
+  //! Generic msg_handler method: insert the message.
+  void handle(gr_message_sptr msg) { insert_tail (msg); }
+
+  /*!
+   * \brief Insert message at tail of queue.
+   * \param msg message
+   *
+   * Block if queue if full.
+   */
+  void insert_tail(gr_message_sptr msg);
+
+  /*!
+   * \brief Delete message from head of queue and return it.
+   * Block if no message is available.
+   */
+  gr_message_sptr delete_head();
+
+  /*!
+   * \brief If there's a message in the q, delete it and return it.
+   * If no message is available, return 0.
+   */
+  gr_message_sptr delete_head_nowait();
+
+  //! Delete all messages from the queue
+  void flush();
+
+  //! is the queue empty?
+  bool empty_p() const { return d_count == 0; }
+
+  //! is the queue full?
+  bool full_p() const { return d_limit != 0 && d_count >= d_limit; }
+
+  //! return number of messages in queue
+  unsigned int count() const { return d_count; }
+
+  //! return limit on number of message in queue.  0 -> unbounded
+  unsigned int limit() const { return d_limit; }
+
+};
+
+#endif /* INCLUDED_GR_MSG_QUEUE_H */