gvpe/src/iom.C

/*
    iom.C -- I/O multiplexor
 
    This program 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 of the License, or
    (at your option) any later version.
 
    This program 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. 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "config.h"

#include <sys/time.h>

#include <algorithm>
#include <functional>

#include "slog.h"
#include "iom.h"

inline bool lowest_first (const time_watcher *a, const time_watcher *b)
{
  return a->at > b->at;
}

tstamp NOW;

io_manager iom;

void time_watcher::set (tstamp when)
{
  iom.unreg (this);
  at = when;
  iom.reg (this);
}

void time_watcher::trigger ()
{
  iom.unreg (this);
  call (at);
  iom.reg (this);
}

void time_watcher::start ()
{
  iom.unreg (this);
  iom.reg (this);
}

void io_manager::reg (int fd, short events, io_watcher *w)
{
  pollfd pfd;

  pfd.fd     = fd;
  pfd.events = events;

  pfs.push_back (pfd);
  iow.push_back (w);
}

void io_manager::unreg (io_watcher *w)
{
  unsigned int sz = iow.size ();
  unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();

  if (i != sz)
    {
      if (sz == 1)
        {
          pfs.clear ();
          iow.clear ();
        }
      else if (i == sz - 1)
        {
          iow.pop_back ();
          pfs.pop_back ();
        }
      else
        {
          iow[i] = iow[sz - 1]; iow.pop_back ();
          pfs[i] = pfs[sz - 1]; pfs.pop_back ();
        }
    }
}

void io_manager::reg (time_watcher *w)
{
  tw.push_back (w);
  push_heap (tw.begin (), tw.end (), lowest_first);
}

void io_manager::unreg (time_watcher *w)
{
  unsigned int sz = tw.size ();
  unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();

  if (i != sz)
    {
      if (i != sz - 1)
        tw[i] = tw[sz - 1];

      tw.pop_back ();
      make_heap (tw.begin (), tw.end (), lowest_first);
    }
}

inline void set_now (void)
{
  struct timeval tv;

  gettimeofday (&tv, 0);

  NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
}

void io_manager::loop ()
{
  set_now ();

  for (;;)
    {
      while (tw[0]->at <= NOW)
        {
          pop_heap (tw.begin (), tw.end (), lowest_first);
          time_watcher *w = *(tw.end () - 1);

          if (w->at >= 0)
            {
              w->call (w->at);
              push_heap (tw.begin (), tw.end (), lowest_first);
            }
          else
            tw.pop_back ();
        }

      int timeout = (int) ((tw[0]->at - NOW) * 1000);

      int fds = poll (&pfs[0], pfs.size (), timeout);

      set_now ();

      for (unsigned int i = iow.size (); fds > 0 && i--; )
        if (pfs[i].revents)
          {
            --fds;
            iow[i]->call (pfs[i].revents);
          }
    }
}

void io_manager::idle_cb (tstamp &ts)
{
  ts = NOW + 86400; // wake up every day, for no good reason
}

io_manager::io_manager ()
{
  set_now ();
  idle = new time_watcher (this, &io_manager::idle_cb);
  idle->start (0);
}

io_manager::~io_manager ()
{
  //
}

Revision:	1.4
Committed:	Fri Mar 21 23:17:01 2003 UTC (23 years, 6 months ago) by pcg
Content type:	text/plain
Branch:	MAIN
Changes since 1.3:	+46 -31 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
2			iom.C -- I/O multiplexor
3
4			This program is free software; you can redistribute it and/or modify
5			it under the terms of the GNU General Public License as published by
6			the Free Software Foundation; either version 2 of the License, or
7			(at your option) any later version.
8
9			This program is distributed in the hope that it will be useful,
10			but WITHOUT ANY WARRANTY; without even the implied warranty of
11			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12			GNU General Public License for more details.
13
14			You should have received a copy of the GNU General Public License
15			along with this program; if not, write to the Free Software
16			Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17			*/
18
19			#include "config.h"
20
21			#include <sys/time.h>
22
23			#include <algorithm>
24			#include <functional>
25
26			#include "slog.h"
27			#include "iom.h"
28
29			inline bool lowest_first (const time_watcher a, const time_watcher b)
30			{
31			return a->at > b->at;
32			}
33
34	pcg	1.2	tstamp NOW;
35	pcg	1.1
36			io_manager iom;
37
38	pcg	1.2	void time_watcher::set (tstamp when)
39	pcg	1.1	{
40			iom.unreg (this);
41			at = when;
42			iom.reg (this);
43			}
44
45	pcg	1.4	void time_watcher::trigger ()
46			{
47			iom.unreg (this);
48			call (at);
49			iom.reg (this);
50			}
51
52			void time_watcher::start ()
53			{
54			iom.unreg (this);
55			iom.reg (this);
56			}
57
58	pcg	1.1	void io_manager::reg (int fd, short events, io_watcher *w)
59			{
60			pollfd pfd;
61
62			pfd.fd = fd;
63			pfd.events = events;
64
65			pfs.push_back (pfd);
66			iow.push_back (w);
67			}
68
69			void io_manager::unreg (io_watcher *w)
70			{
71			unsigned int sz = iow.size ();
72			unsigned int i = find (iow.begin (), iow.end (), w) - iow.begin ();
73
74			if (i != sz)
75			{
76			if (sz == 1)
77			{
78			pfs.clear ();
79			iow.clear ();
80			}
81			else if (i == sz - 1)
82			{
83			iow.pop_back ();
84			pfs.pop_back ();
85			}
86			else
87			{
88			iow[i] = iow[sz - 1]; iow.pop_back ();
89			pfs[i] = pfs[sz - 1]; pfs.pop_back ();
90			}
91			}
92			}
93
94			void io_manager::reg (time_watcher *w)
95			{
96			tw.push_back (w);
97			push_heap (tw.begin (), tw.end (), lowest_first);
98			}
99
100			void io_manager::unreg (time_watcher *w)
101			{
102			unsigned int sz = tw.size ();
103			unsigned int i = find (tw.begin (), tw.end (), w) - tw.begin ();
104
105			if (i != sz)
106			{
107	pcg	1.4	if (i != sz - 1)
108			tw[i] = tw[sz - 1];
109	pcg	1.1
110	pcg	1.4	tw.pop_back ();
111			make_heap (tw.begin (), tw.end (), lowest_first);
112	pcg	1.1	}
113			}
114
115			inline void set_now (void)
116			{
117			struct timeval tv;
118
119			gettimeofday (&tv, 0);
120
121	pcg	1.2	NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
122	pcg	1.1	}
123
124			void io_manager::loop ()
125			{
126			set_now ();
127
128	pcg	1.4	for (;;)
129	pcg	1.1	{
130	pcg	1.4	while (tw[0]->at <= NOW)
131			{
132			pop_heap (tw.begin (), tw.end (), lowest_first);
133			time_watcher w = (tw.end () - 1);
134	pcg	1.1
135	pcg	1.4	if (w->at >= 0)
136			{
137			w->call (w->at);
138			push_heap (tw.begin (), tw.end (), lowest_first);
139			}
140			else
141			tw.pop_back ();
142			}
143	pcg	1.1
144	pcg	1.4	int timeout = (int) ((tw[0]->at - NOW) * 1000);
145	pcg	1.1
146	pcg	1.4	int fds = poll (&pfs[0], pfs.size (), timeout);
147	pcg	1.1
148	pcg	1.4	set_now ();
149	pcg	1.1
150	pcg	1.4	for (unsigned int i = iow.size (); fds > 0 && i--; )
151			if (pfs[i].revents)
152			{
153			--fds;
154			iow[i]->call (pfs[i].revents);
155			}
156	pcg	1.1	}
157			}
158
159	pcg	1.4	void io_manager::idle_cb (tstamp &ts)
160			{
161			ts = NOW + 86400; // wake up every day, for no good reason
162			}
163
164	pcg	1.1	io_manager::io_manager ()
165			{
166			set_now ();
167	pcg	1.4	idle = new time_watcher (this, &io_manager::idle_cb);
168			idle->start (0);
169	pcg	1.1	}
170
171			io_manager::~io_manager ()
172			{
173			//
174			}
175