base/pollevent.hh

   1 /*
   2  * Copyright (c) 2003 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #ifndef __POLLEVENT_H__
  30 #define __POLLEVENT_H__
  31
  32 #include <vector>
  33 #include <poll.h>
  34 #include "universe.hh"
  35
  36 class PollEvent
  37 {
  38   private:
  39     friend class PollQueue;
  40
  41   protected:
  42     pollfd pfd;
  43     PollQueue *queue;
  44     bool enabled;
  45
  46   public:
  47     PollEvent(int fd, int event);
  48     virtual ~PollEvent();
  49
  50     void disable();
  51     void enable();
  52     virtual void process(int revent) = 0;
  53 };
  54
  55 class PollQueue
  56 {
  57   private:
  58     typedef std::vector<PollEvent *> eventvec_t;
  59     eventvec_t events;
  60
  61     pollfd *poll_fds;
  62     int max_size;
  63     int num_fds;
  64
  65   public:
  66     PollQueue();
  67     ~PollQueue();
  68
  69     void copy();
  70     void remove(PollEvent *event);
  71     void schedule(PollEvent *event);
  72     void service();
  73
  74   protected:
  75     static bool handler;
  76     static struct sigaction oldio;
  77     static struct sigaction oldalrm;
  78
  79   public:
  80     static void setupAsyncIO(int fd, bool set);
  81     static void handleIO(int);
  82     static void handleALRM(int);
  83     static void removeHandler();
  84     static void setupHandler();
  85 };
  86
  87 extern PollQueue pollQueue;
  88
  89 #endif // __POLLEVENT_H__