gr_msg_queue.h

Go to the documentation of this file.
00001 /* -*- c++ -*- */
00002 /*
00003  * Copyright 2005 Free Software Foundation, Inc.
00004  * 
00005  * This file is part of GNU Radio
00006  * 
00007  * GNU Radio is free software; you can redistribute it and/or modify
00008  * it under the terms of the GNU General Public License as published by
00009  * the Free Software Foundation; either version 3, or (at your option)
00010  * any later version.
00011  * 
00012  * GNU Radio is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015  * GNU General Public License for more details.
00016  * 
00017  * You should have received a copy of the GNU General Public License
00018  * along with GNU Radio; see the file COPYING.  If not, write to
00019  * the Free Software Foundation, Inc., 51 Franklin Street,
00020  * Boston, MA 02110-1301, USA.
00021  */
00022 #ifndef INCLUDED_GR_MSG_QUEUE_H
00023 #define INCLUDED_GR_MSG_QUEUE_H
00024 
00025 #include <gr_msg_handler.h>
00026 #include <gnuradio/omnithread.h>
00027 
00028 class gr_msg_queue;
00029 typedef boost::shared_ptr<gr_msg_queue> gr_msg_queue_sptr;
00030 
00031 gr_msg_queue_sptr gr_make_msg_queue(unsigned int limit=0);
00032 
00033 /*!
00034  * \brief thread-safe message queue
00035  * \ingroup misc
00036  */
00037 class gr_msg_queue : public gr_msg_handler {
00038   omni_mutex            d_mutex;
00039   omni_condition        d_not_empty;
00040   omni_condition        d_not_full;
00041   gr_message_sptr       d_head;
00042   gr_message_sptr       d_tail;
00043   unsigned int          d_count;    // # of messages in queue.
00044   unsigned int          d_limit;    // max # of messages in queue.  0 -> unbounded
00045 
00046 public:
00047   gr_msg_queue(unsigned int limit);
00048   ~gr_msg_queue();
00049 
00050   //! Generic msg_handler method: insert the message.
00051   void handle(gr_message_sptr msg) { insert_tail (msg); }
00052 
00053   /*!
00054    * \brief Insert message at tail of queue.
00055    * \param msg message
00056    *
00057    * Block if queue if full.
00058    */
00059   void insert_tail(gr_message_sptr msg);
00060 
00061   /*!
00062    * \brief Delete message from head of queue and return it.
00063    * Block if no message is available.
00064    */
00065   gr_message_sptr delete_head();
00066 
00067   /*!
00068    * \brief If there's a message in the q, delete it and return it.
00069    * If no message is available, return 0.
00070    */
00071   gr_message_sptr delete_head_nowait();
00072   
00073   //! Delete all messages from the queue
00074   void flush();
00075 
00076   //! is the queue empty?
00077   bool empty_p() const { return d_count == 0; }
00078   
00079   //! is the queue full?
00080   bool full_p() const { return d_limit != 0 && d_count >= d_limit; }
00081   
00082   //! return number of messages in queue
00083   unsigned int count() const { return d_count; }
00084 
00085   //! return limit on number of message in queue.  0 -> unbounded
00086   unsigned int limit() const { return d_limit; }
00087 
00088 };
00089 
00090 #endif /* INCLUDED_GR_MSG_QUEUE_H */

Generated on Wed Jul 29 06:29:47 2009 for GNU Radio 3.2.2 C++ API by  doxygen 1.5.9