rxvt-unicode/src/iom.C

/*
    iom.C -- generic I/O multiplexer
    Copyright (C) 2003-2006 Marc Lehmann <gvpe@schmorp.de>
 
    This file is part of GVPE.

    GVPE 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 gvpe; if not, write to the Free Software
    Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include "iom.h"

#include <cstdio>
#include <cstdlib>
#include <cerrno>
#include <cassert>

#include <sys/types.h>
#include <sys/time.h>

#if 1 // older unices need these includes for select (2)
# include <unistd.h>
# include <time.h>
#endif

#if IOM_CHILD
# include <sys/wait.h>
#endif

#if IOM_SIG
# include <csignal>
# include <fcntl.h>
#endif

// if the BSDs would at least be marginally POSIX-compatible.. *sigh*
// until that happens, sys/select.h must come last
#include <sys/select.h>

#define TIMEVAL timeval
#define TV_FRAC tv_usec
#define TV_MULT 1000000L

#ifndef IOM_LIBEVENT
#if IOM_IO
static io_manager_vec<io_watcher>    iow;
#endif
#if IOM_TIME
static io_manager_vec<time_watcher>  tw;
#endif
#endif

#if IOM_CHECK
static io_manager_vec<check_watcher> cw;
#endif
#if IOM_IDLE
static io_manager_vec<idle_watcher>  iw;
#endif

#if IOM_SIG
static int sigpipe[2]; // signal signalling pipe
static sigset_t sigs;
struct sig_vec : io_manager_vec<sig_watcher> {
  int pending;
  sig_vec ()
    : pending (false)
    { }
};
static vector<sig_vec *> sw;
#endif

#if IOM_CHILD
static io_manager_vec<child_watcher>  pw;
#endif

// this is a dummy time watcher to ensure that the first
// time watcher is _always_ valid, this gets rid of a lot
// of null-pointer-checks
// (must come _before_ iom is being defined)
static struct tw0 : time_watcher
{
  void cb (time_watcher &w)
  {
    // should never get called
    // reached end-of-time, or tstamp has a bogus definition,
    // or compiler initialisation order broken, or something else :)
    abort ();
  }

  tw0 ()
  : time_watcher (this, &tw0::cb)
  { }
} tw0;

tstamp NOW;

#if IOM_CHILD
// sig_watcher for child signal(s)
static struct sw0 : sig_watcher
{
  void cb (sig_watcher &w)
  {
    // SIGCHLD, call corresponding watchera
    pid_t pid;
    int status;

    while ((pid = waitpid (-1, &status, WNOHANG)) > 0)
      for (int i = pw.size (); i--; )
        {
          child_watcher *w = pw[i];

          if (!w)
            pw.erase_unordered (i);
          else if (w->pid == pid)
            {
              io_manager::unreg (*w);
              w->call (*w, status);
            }
         }
  }

  sw0 ()
  : sig_watcher (this, &sw0::cb)
  { }
} sw0;
#endif

#if IOM_TIME
tstamp io_manager::now ()
{
  struct timeval tv;

  gettimeofday (&tv, 0);
  return (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000.;
}

void io_manager::set_now ()
{
  NOW = now ();
}
#endif

static bool iom_valid;

// used for initialisation only
static struct init {
  init ()
  {
#ifdef IOM_PREINIT
    { IOM_PREINIT }
#endif
#ifdef IOM_LIBEVENT
    event_init ();
#endif
    iom_valid = true;

#if IOM_SIG
    sigemptyset (&sigs);

    if (pipe (sigpipe))
      {
        perror ("io_manager: unable to create signal pipe, aborting.");
        abort ();
      }

    fcntl (sigpipe[0], F_SETFL, O_NONBLOCK); fcntl (sigpipe[0], F_SETFD, FD_CLOEXEC);
    fcntl (sigpipe[1], F_SETFL, O_NONBLOCK); fcntl (sigpipe[1], F_SETFD, FD_CLOEXEC);
#endif

#if IOM_CHILD
    sw0.start (SIGCHLD);
#endif

#if IOM_TIME
    io_manager::set_now ();

    tw0.start (TSTAMP_MAX);
#endif

#ifdef IOM_POSTINIT
    { IOM_POSTINIT }
#endif
  }

  ~init ()
  {
    iom_valid = false;
  }

  static void required ();
} init;

void
init::required ()
{
  if (!iom_valid)
    {
      write (2, "io_manager: early registration attempt, aborting.\n",
                sizeof ("io_manager: early registration attempt, aborting.\n") - 1);
      abort ();
    }
}

template<class watcher>
void io_manager::reg (watcher &w, io_manager_vec<watcher> &queue)
{
  init::required ();

  if (!w.active)
    {
      queue.push_back (&w);
      w.active = queue.size ();
    }
}

template<class watcher>
void io_manager::unreg (watcher &w, io_manager_vec<watcher> &queue)
{
  if (!iom_valid)
    return;

  if (w.active)
    {
      queue [w.active - 1] = 0;
      w.active = 0;
    }
}

#if IOM_TIME
# ifdef IOM_LIBEVENT
  void iom_time_c_callback (int fd, short events, void *data)
  {
    time_watcher *w = static_cast<time_watcher *>(data);
    w->call (*w);
  }
# else
  void io_manager::reg   (time_watcher &w)  { io_manager::reg   (w, tw); }
  void io_manager::unreg (time_watcher &w)  { io_manager::unreg (w, tw); }
# endif

void time_watcher::trigger ()
{
  call (*this);
  start ();
}
#endif

#if IOM_IO
# ifdef IOM_LIBEVENT
  void iom_io_c_callback (int fd, short events, void *data)
  {
    io_watcher *w = static_cast<io_watcher *>(data);
    w->call (*w, events);
  }
# else
  void io_manager::reg   (io_watcher &w)    { io_manager::reg   (w, iow); }
  void io_manager::unreg (io_watcher &w)    { io_manager::unreg (w, iow); }
# endif
#endif

#if IOM_CHECK
void io_manager::reg   (check_watcher &w) { io_manager::reg   (w, cw); }
void io_manager::unreg (check_watcher &w) { io_manager::unreg (w, cw); }
#endif

#if IOM_IDLE
void io_manager::reg   (idle_watcher &w)  { io_manager::reg   (w, iw); }
void io_manager::unreg (idle_watcher &w)  { io_manager::unreg (w, iw); }
#endif

#if IOM_SIG
static void
sighandler (int signum)
{
  sw [signum - 1]->pending = true;

  // we use a pipe for signal notifications, as most current
  // OSes (Linux...) do not implement pselect correctly. ugh.
  char ch = signum; // actual content not used
  write (sigpipe[1], &ch, 1);
}

void io_manager::reg (sig_watcher &w)
{
  init::required ();

  assert (0 < w.signum);

  sw.reserve (w.signum);

  while (sw.size () < w.signum) // pathetic
    sw.push_back (0);

  sig_vec *&sv = sw[w.signum - 1];

  if (!sv)
    {
      sv = new sig_vec;

      sigaddset (&sigs, w.signum);
      sigprocmask (SIG_BLOCK, &sigs, NULL);

      struct sigaction sa;
      sa.sa_handler = sighandler;
      sigfillset (&sa.sa_mask);
      sa.sa_flags = SA_RESTART;

      if (sigaction (w.signum, &sa, 0))
        {
          perror ("io_manager: error while installing signal handler, ignoring.");
          abort ();
        }

    }

  io_manager::reg (w, *sv);
}

void io_manager::unreg (sig_watcher &w)
{
  if (!w.active || !iom_valid)
    return;

  assert (0 < w.signum && w.signum <= sw.size ());
  
  io_manager::unreg (w, *sw[w.signum - 1]);
}

void sig_watcher::start (int signum)
{
  stop ();
  this->signum = signum;
  io_manager::reg (*this);
}
#endif

#if IOM_CHILD
void io_manager::reg   (child_watcher &w) { io_manager::reg   (w, pw); }
void io_manager::unreg (child_watcher &w) { io_manager::unreg (w, pw); }
#endif

void io_manager::loop ()
{
  init::required ();

  #if IOM_TIME
    set_now ();
  #endif

  for (;;)
    {
      #ifndef IOM_LIBEVENT
      #if IOM_TIME
        // call pending time watchers
        {
          bool activity;

          do
            {
              activity = false;

              for (int i = tw.size (); i--; )
                if (!tw[i])
                  tw.erase_unordered (i);
                else if (tw[i]->at <= NOW)
                  {
                    time_watcher &w = *tw[i];
                    
                    unreg (w);
                    w.call (w);

                    activity = true;
                  }
            }
          while (activity);
        }
      #endif
      #endif

      #if IOM_CHECK
        // call all check watchers
        for (int i = cw.size (); i--; )
          if (!cw[i])
            cw.erase_unordered (i);
          else
            cw[i]->call (*cw[i]);
      #endif

      struct TIMEVAL *to = 0;
      struct TIMEVAL tval;

#if IOM_IDLE
      if (iw.size ())
        {
          tval.tv_sec  = 0;
          tval.TV_FRAC = 0;
          to = &tval;
        }
      else
#endif
#ifndef IOM_LIBEVENT
        {
          #if IOM_TIME
            // find earliest active watcher
            time_watcher *next = tw[0]; // the first time-watcher must exist at ALL times

            for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
              if (*i && (*i)->at < next->at)
                next = *i;

            if (next->at > NOW && next != tw[0])
              {
                double diff = next->at - NOW;
                tval.tv_sec  = (int)diff;
                tval.TV_FRAC = (int) ((diff - tval.tv_sec) * TV_MULT);
                to = &tval;
              }
          #endif
        }

#if IOM_IO || IOM_SIG
      fd_set rfd, wfd;

      FD_ZERO (&rfd);
      FD_ZERO (&wfd);

      int fds = 0;

      #if IOM_IO
        for (io_manager_vec<io_watcher>::const_iterator i = iow.end (); i-- > iow.begin (); )
          if (*i)
            {
              if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
              if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);

              if ((*i)->fd >= fds) fds = (*i)->fd + 1;
            }
      #endif

      if (!to && !fds) //TODO: also check idle_watchers and check_watchers?
        break; // no events

      #if IOM_SIG
        FD_SET (sigpipe[0], &rfd);
        if (sigpipe[0] >= fds) fds = sigpipe[0] + 1;
      #endif

      #if IOM_SIG
        // there is no race, as we use a pipe for signals, so select
        // will return if a signal is caught.
        sigprocmask (SIG_UNBLOCK, &sigs, NULL);
      #endif
      fds = select (fds, &rfd, &wfd, NULL, to);
      #if IOM_SIG
        sigprocmask (SIG_BLOCK, &sigs, NULL);
      #endif

#else
      if (to)
        event_loop (EVLOOP_NONBLOCK);
      else
        event_loop (EVLOOP_ONCE);
#endif

      #if IOM_TIME
        {
          // update time, try to compensate for gross non-monotonic time changes
          tstamp diff = NOW;
          set_now ();
          diff = NOW - diff;

          if (diff < 0)
            for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
              if (*i)
                (*i)->at += diff;
        }
      #endif

#ifndef IOM_LIBEVENT
      if (fds > 0)
        {
          #if IOM_SIG
            if (FD_ISSET (sigpipe[0], &rfd))
              {
                char ch;

                while (read (sigpipe[0], &ch, 1) > 0)
                  ;

                for (vector<sig_vec *>::iterator svp = sw.end (); svp-- > sw.begin (); )
                  if (*svp && (*svp)->pending)
                    {
                      sig_vec &sv = **svp;
                      for (int i = sv.size (); i--; )
                        if (!sv[i])
                          sv.erase_unordered (i);
                        else
                          sv[i]->call (*sv[i]);

                      sv.pending = false;
                    }
              }
          #endif

          #if IOM_IO
            for (int i = iow.size (); i--; )
              if (!iow[i])
                iow.erase_unordered (i);
              else
                {
                  io_watcher &w = *iow[i];
                  short revents = w.events;

                  if (!FD_ISSET (w.fd, &rfd)) revents &= ~EVENT_READ;
                  if (!FD_ISSET (w.fd, &wfd)) revents &= ~EVENT_WRITE;

                  if (revents)
                    w.call (w, revents);
                }
          #endif
        }
      else if (fds < 0 && errno != EINTR)
        {
          perror ("io_manager: fatal error while waiting for I/O or time event, aborting.");
          abort ();
        }
#else
      if (0)
        ;
#endif
#if IOM_IDLE
      else
        for (int i = iw.size (); i--; )
          if (!iw[i])
            iw.erase_unordered (i);
          else
            iw[i]->call (*iw[i]);
#endif

#elif IOM_TIME
      if (!to)
        break;

      select (0, 0, 0, 0, to);
      set_now ();
      break;
#endif
    }
}

Revision:	1.38
Committed:	Thu Oct 25 10:44:14 2007 UTC (16 years, 8 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.37:	+165 -128 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	/*
2	root	1.23	iom.C -- generic I/O multiplexer
3	root	1.34	Copyright (C) 2003-2006 Marc Lehmann <gvpe@schmorp.de>
4	pcg	1.1
5	root	1.30	This file is part of GVPE.
6
7			GVPE is free software; you can redistribute it and/or modify
8	pcg	1.1	it under the terms of the GNU General Public License as published by
9			the Free Software Foundation; either version 2 of the License, or
10			(at your option) any later version.
11
12			This program is distributed in the hope that it will be useful,
13			but WITHOUT ANY WARRANTY; without even the implied warranty of
14			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15			GNU General Public License for more details.
16
17			You should have received a copy of the GNU General Public License
18	root	1.30	along with gvpe; if not, write to the Free Software
19	root	1.29	Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20	pcg	1.1	*/
21
22	root	1.19	#include "iom.h"
23
24	pcg	1.1	#include <cstdio>
25	pcg	1.8	#include <cstdlib>
26			#include <cerrno>
27	root	1.33	#include <cassert>
28	pcg	1.1
29	root	1.33	#include <sys/types.h>
30	pcg	1.11	#include <sys/time.h>
31
32	pcg	1.14	#if 1 // older unices need these includes for select (2)
33	pcg	1.11	# include <unistd.h>
34	root	1.19	# include <time.h>
35			#endif
36
37	root	1.33	#if IOM_CHILD
38			# include <sys/wait.h>
39			#endif
40
41	root	1.19	#if IOM_SIG
42	root	1.27	# include <csignal>
43	root	1.19	# include <fcntl.h>
44	pcg	1.11	#endif
45
46			// if the BSDs would at least be marginally POSIX-compatible.. sigh
47			// until that happens, sys/select.h must come last
48	pcg	1.1	#include <sys/select.h>
49
50	root	1.19	#define TIMEVAL timeval
51			#define TV_FRAC tv_usec
52			#define TV_MULT 1000000L
53	pcg	1.1
54	root	1.38	#ifndef IOM_LIBEVENT
55	root	1.19	#if IOM_IO
56			static io_manager_vec<io_watcher> iow;
57			#endif
58	root	1.38	#if IOM_TIME
59			static io_manager_vec<time_watcher> tw;
60			#endif
61			#endif
62
63	root	1.19	#if IOM_CHECK
64			static io_manager_vec<check_watcher> cw;
65			#endif
66			#if IOM_IDLE
67			static io_manager_vec<idle_watcher> iw;
68			#endif
69	root	1.38
70	root	1.19	#if IOM_SIG
71			static int sigpipe[2]; // signal signalling pipe
72			static sigset_t sigs;
73			struct sig_vec : io_manager_vec<sig_watcher> {
74			int pending;
75			sig_vec ()
76			: pending (false)
77			{ }
78			};
79			static vector<sig_vec *> sw;
80			#endif
81	root	1.38
82	root	1.33	#if IOM_CHILD
83			static io_manager_vec<child_watcher> pw;
84			#endif
85	pcg	1.8
86	pcg	1.10	// this is a dummy time watcher to ensure that the first
87			// time watcher is _always_ valid, this gets rid of a lot
88			// of null-pointer-checks
89			// (must come _before_ iom is being defined)
90	pcg	1.13	static struct tw0 : time_watcher
91	root	1.33	{
92			void cb (time_watcher &w)
93	pcg	1.10	{
94	root	1.33	// should never get called
95			// reached end-of-time, or tstamp has a bogus definition,
96			// or compiler initialisation order broken, or something else :)
97			abort ();
98			}
99	pcg	1.10
100	root	1.33	tw0 ()
101			: time_watcher (this, &tw0::cb)
102			{ }
103			} tw0;
104	pcg	1.10
105	pcg	1.1	tstamp NOW;
106	root	1.19
107	root	1.33	#if IOM_CHILD
108			// sig_watcher for child signal(s)
109			static struct sw0 : sig_watcher
110			{
111			void cb (sig_watcher &w)
112			{
113			// SIGCHLD, call corresponding watchera
114			pid_t pid;
115			int status;
116
117			while ((pid = waitpid (-1, &status, WNOHANG)) > 0)
118			for (int i = pw.size (); i--; )
119			{
120			child_watcher *w = pw[i];
121
122			if (!w)
123			pw.erase_unordered (i);
124			else if (w->pid == pid)
125			{
126	root	1.35	io_manager::unreg (*w);
127	root	1.33	w->call (*w, status);
128			}
129			}
130			}
131
132			sw0 ()
133			: sig_watcher (this, &sw0::cb)
134			{ }
135			} sw0;
136			#endif
137
138	root	1.19	#if IOM_TIME
139	root	1.24	tstamp io_manager::now ()
140	root	1.19	{
141			struct timeval tv;
142
143			gettimeofday (&tv, 0);
144	root	1.24	return (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000.;
145			}
146
147			void io_manager::set_now ()
148			{
149			NOW = now ();
150	root	1.19	}
151			#endif
152
153	pcg	1.8	static bool iom_valid;
154	root	1.19
155			// used for initialisation only
156			static struct init {
157			init ()
158			{
159	root	1.37	#ifdef IOM_PREINIT
160			{ IOM_PREINIT }
161			#endif
162	root	1.38	#ifdef IOM_LIBEVENT
163			event_init ();
164			#endif
165	root	1.33	iom_valid = true;
166
167	root	1.19	#if IOM_SIG
168			sigemptyset (&sigs);
169
170			if (pipe (sigpipe))
171			{
172			perror ("io_manager: unable to create signal pipe, aborting.");
173			abort ();
174			}
175
176	root	1.25	fcntl (sigpipe[0], F_SETFL, O_NONBLOCK); fcntl (sigpipe[0], F_SETFD, FD_CLOEXEC);
177			fcntl (sigpipe[1], F_SETFL, O_NONBLOCK); fcntl (sigpipe[1], F_SETFD, FD_CLOEXEC);
178	root	1.19	#endif
179
180	root	1.33	#if IOM_CHILD
181			sw0.start (SIGCHLD);
182			#endif
183	root	1.19
184			#if IOM_TIME
185	root	1.24	io_manager::set_now ();
186	root	1.19
187			tw0.start (TSTAMP_MAX);
188			#endif
189	root	1.37
190			#ifdef IOM_POSTINIT
191			{ IOM_POSTINIT }
192			#endif
193	root	1.19	}
194
195	root	1.31	~init ()
196			{
197			iom_valid = false;
198			}
199
200	root	1.19	static void required ();
201			} init;
202
203			void
204			init::required ()
205			{
206			if (!iom_valid)
207			{
208			write (2, "io_manager: early registration attempt, aborting.\n",
209			sizeof ("io_manager: early registration attempt, aborting.\n") - 1);
210			abort ();
211			}
212			}
213	pcg	1.1
214	pcg	1.4	template<class watcher>
215	root	1.19	void io_manager::reg (watcher &w, io_manager_vec<watcher> &queue)
216	pcg	1.4	{
217	root	1.19	init::required ();
218	pcg	1.8
219	root	1.19	if (!w.active)
220	pcg	1.8	{
221	root	1.19	queue.push_back (&w);
222			w.active = queue.size ();
223	pcg	1.8	}
224	pcg	1.4	}
225
226			template<class watcher>
227	root	1.19	void io_manager::unreg (watcher &w, io_manager_vec<watcher> &queue)
228	pcg	1.4	{
229	pcg	1.8	if (!iom_valid)
230			return;
231	pcg	1.4
232	root	1.19	if (w.active)
233	pcg	1.8	{
234	root	1.19	queue [w.active - 1] = 0;
235			w.active = 0;
236	pcg	1.8	}
237	pcg	1.4	}
238
239			#if IOM_TIME
240	root	1.38	# ifdef IOM_LIBEVENT
241			void iom_time_c_callback (int fd, short events, void *data)
242			{
243			time_watcher w = static_cast<time_watcher >(data);
244			w->call (*w);
245			}
246			# else
247			void io_manager::reg (time_watcher &w) { io_manager::reg (w, tw); }
248			void io_manager::unreg (time_watcher &w) { io_manager::unreg (w, tw); }
249			# endif
250
251	pcg	1.1	void time_watcher::trigger ()
252			{
253			call (*this);
254	root	1.38	start ();
255	pcg	1.1	}
256	pcg	1.8	#endif
257	pcg	1.3
258	pcg	1.8	#if IOM_IO
259	root	1.38	# ifdef IOM_LIBEVENT
260			void iom_io_c_callback (int fd, short events, void *data)
261			{
262			io_watcher w = static_cast<io_watcher >(data);
263			w->call (*w, events);
264			}
265			# else
266			void io_manager::reg (io_watcher &w) { io_manager::reg (w, iow); }
267			void io_manager::unreg (io_watcher &w) { io_manager::unreg (w, iow); }
268			# endif
269	pcg	1.4	#endif
270	pcg	1.1
271	pcg	1.4	#if IOM_CHECK
272	root	1.19	void io_manager::reg (check_watcher &w) { io_manager::reg (w, cw); }
273			void io_manager::unreg (check_watcher &w) { io_manager::unreg (w, cw); }
274	pcg	1.4	#endif
275	pcg	1.1
276	pcg	1.7	#if IOM_IDLE
277	root	1.19	void io_manager::reg (idle_watcher &w) { io_manager::reg (w, iw); }
278			void io_manager::unreg (idle_watcher &w) { io_manager::unreg (w, iw); }
279	pcg	1.7	#endif
280
281	root	1.19	#if IOM_SIG
282			static void
283			sighandler (int signum)
284	pcg	1.1	{
285	root	1.19	sw [signum - 1]->pending = true;
286	pcg	1.1
287	root	1.19	// we use a pipe for signal notifications, as most current
288			// OSes (Linux...) do not implement pselect correctly. ugh.
289			char ch = signum; // actual content not used
290			write (sigpipe[1], &ch, 1);
291	pcg	1.16	}
292
293	root	1.19	void io_manager::reg (sig_watcher &w)
294	pcg	1.16	{
295	root	1.32	init::required ();
296
297	root	1.19	assert (0 < w.signum);
298	pcg	1.16
299	root	1.19	sw.reserve (w.signum);
300	pcg	1.16
301	root	1.19	while (sw.size () < w.signum) // pathetic
302			sw.push_back (0);
303	pcg	1.16
304	root	1.19	sig_vec *&sv = sw[w.signum - 1];
305	pcg	1.16
306			if (!sv)
307			{
308			sv = new sig_vec;
309
310	root	1.19	sigaddset (&sigs, w.signum);
311			sigprocmask (SIG_BLOCK, &sigs, NULL);
312
313	pcg	1.16	struct sigaction sa;
314	root	1.19	sa.sa_handler = sighandler;
315	pcg	1.16	sigfillset (&sa.sa_mask);
316	root	1.19	sa.sa_flags = SA_RESTART;
317	pcg	1.16
318	root	1.19	if (sigaction (w.signum, &sa, 0))
319	pcg	1.16	{
320	root	1.19	perror ("io_manager: error while installing signal handler, ignoring.");
321	pcg	1.16	abort ();
322			}
323	root	1.19
324	pcg	1.16	}
325
326	root	1.19	io_manager::reg (w, *sv);
327	pcg	1.16	}
328
329	root	1.19	void io_manager::unreg (sig_watcher &w)
330	pcg	1.16	{
331	root	1.32	if (!w.active \|\| !iom_valid)
332	root	1.19	return;
333
334			assert (0 < w.signum && w.signum <= sw.size ());
335	pcg	1.16
336	root	1.19	io_manager::unreg (w, *sw[w.signum - 1]);
337	pcg	1.16	}
338
339			void sig_watcher::start (int signum)
340			{
341			stop ();
342			this->signum = signum;
343	root	1.19	io_manager::reg (*this);
344	pcg	1.16	}
345			#endif
346	root	1.19
347	root	1.33	#if IOM_CHILD
348			void io_manager::reg (child_watcher &w) { io_manager::reg (w, pw); }
349			void io_manager::unreg (child_watcher &w) { io_manager::unreg (w, pw); }
350			#endif
351
352	pcg	1.1	void io_manager::loop ()
353			{
354	root	1.19	init::required ();
355
356	root	1.38	#if IOM_TIME
357			set_now ();
358			#endif
359	pcg	1.1
360			for (;;)
361			{
362	root	1.38	#ifndef IOM_LIBEVENT
363			#if IOM_TIME
364			// call pending time watchers
365			{
366			bool activity;
367	pcg	1.1
368	root	1.38	do
369			{
370			activity = false;
371	pcg	1.1
372	root	1.38	for (int i = tw.size (); i--; )
373			if (!tw[i])
374			tw.erase_unordered (i);
375			else if (tw[i]->at <= NOW)
376			{
377			time_watcher &w = *tw[i];
378
379			unreg (w);
380			w.call (w);
381	pcg	1.7
382	root	1.38	activity = true;
383			}
384			}
385			while (activity);
386			}
387			#endif
388			#endif
389	pcg	1.6
390	root	1.38	#if IOM_CHECK
391			// call all check watchers
392			for (int i = cw.size (); i--; )
393			if (!cw[i])
394			cw.erase_unordered (i);
395			else
396			cw[i]->call (*cw[i]);
397			#endif
398	pcg	1.12
399	root	1.23	struct TIMEVAL *to = 0;
400			struct TIMEVAL tval;
401
402			#if IOM_IDLE
403			if (iw.size ())
404	pcg	1.12	{
405			tval.tv_sec = 0;
406	root	1.19	tval.TV_FRAC = 0;
407	pcg	1.12	to = &tval;
408			}
409	root	1.23	else
410			#endif
411	root	1.38	#ifndef IOM_LIBEVENT
412	root	1.23	{
413	root	1.38	#if IOM_TIME
414			// find earliest active watcher
415			time_watcher *next = tw[0]; // the first time-watcher must exist at ALL times
416
417			for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
418			if (i && (i)->at < next->at)
419			next = *i;
420	root	1.23
421	root	1.38	if (next->at > NOW && next != tw[0])
422			{
423			double diff = next->at - NOW;
424			tval.tv_sec = (int)diff;
425			tval.TV_FRAC = (int) ((diff - tval.tv_sec) * TV_MULT);
426			to = &tval;
427			}
428			#endif
429	root	1.23	}
430	pcg	1.1
431	root	1.19	#if IOM_IO \|\| IOM_SIG
432	pcg	1.15	fd_set rfd, wfd;
433	pcg	1.1
434			FD_ZERO (&rfd);
435			FD_ZERO (&wfd);
436
437			int fds = 0;
438
439	root	1.38	#if IOM_IO
440			for (io_manager_vec<io_watcher>::const_iterator i = iow.end (); i-- > iow.begin (); )
441			if (*i)
442			{
443			if ((i)->events & EVENT_READ ) FD_SET ((i)->fd, &rfd);
444			if ((i)->events & EVENT_WRITE) FD_SET ((i)->fd, &wfd);
445	pcg	1.1
446	root	1.38	if ((i)->fd >= fds) fds = (i)->fd + 1;
447			}
448			#endif
449	pcg	1.1
450	root	1.23	if (!to && !fds) //TODO: also check idle_watchers and check_watchers?
451	pcg	1.5	break; // no events
452
453	root	1.38	#if IOM_SIG
454			FD_SET (sigpipe[0], &rfd);
455			if (sigpipe[0] >= fds) fds = sigpipe[0] + 1;
456			#endif
457
458			#if IOM_SIG
459			// there is no race, as we use a pipe for signals, so select
460			// will return if a signal is caught.
461			sigprocmask (SIG_UNBLOCK, &sigs, NULL);
462			#endif
463			fds = select (fds, &rfd, &wfd, NULL, to);
464			#if IOM_SIG
465			sigprocmask (SIG_BLOCK, &sigs, NULL);
466			#endif
467	root	1.19
468	root	1.38	#else
469			if (to)
470			event_loop (EVLOOP_NONBLOCK);
471			else
472			event_loop (EVLOOP_ONCE);
473			#endif
474	root	1.19
475	root	1.38	#if IOM_TIME
476			{
477			// update time, try to compensate for gross non-monotonic time changes
478			tstamp diff = NOW;
479			set_now ();
480			diff = NOW - diff;
481
482			if (diff < 0)
483			for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
484			if (*i)
485			(*i)->at += diff;
486			}
487			#endif
488	pcg	1.1
489	root	1.38	#ifndef IOM_LIBEVENT
490	pcg	1.1	if (fds > 0)
491	root	1.19	{
492	root	1.38	#if IOM_SIG
493			if (FD_ISSET (sigpipe[0], &rfd))
494			{
495			char ch;
496	root	1.19
497	root	1.38	while (read (sigpipe[0], &ch, 1) > 0)
498			;
499	pcg	1.1
500	root	1.38	for (vector<sig_vec *>::iterator svp = sw.end (); svp-- > sw.begin (); )
501			if (svp && (svp)->pending)
502			{
503			sig_vec &sv = **svp;
504			for (int i = sv.size (); i--; )
505			if (!sv[i])
506			sv.erase_unordered (i);
507			else
508			sv[i]->call (*sv[i]);
509	pcg	1.4
510	root	1.38	sv.pending = false;
511			}
512			}
513			#endif
514	root	1.19
515	root	1.38	#if IOM_IO
516			for (int i = iow.size (); i--; )
517			if (!iow[i])
518			iow.erase_unordered (i);
519			else
520			{
521			io_watcher &w = *iow[i];
522			short revents = w.events;
523	root	1.19
524	root	1.38	if (!FD_ISSET (w.fd, &rfd)) revents &= ~EVENT_READ;
525			if (!FD_ISSET (w.fd, &wfd)) revents &= ~EVENT_WRITE;
526	root	1.19
527	root	1.38	if (revents)
528			w.call (w, revents);
529			}
530			#endif
531	root	1.19	}
532	pcg	1.8	else if (fds < 0 && errno != EINTR)
533			{
534	root	1.19	perror ("io_manager: fatal error while waiting for I/O or time event, aborting.");
535	pcg	1.8	abort ();
536			}
537	root	1.38	#else
538			if (0)
539			;
540			#endif
541	pcg	1.7	#if IOM_IDLE
542	pcg	1.8	else
543			for (int i = iw.size (); i--; )
544			if (!iw[i])
545			iw.erase_unordered (i);
546			else
547			iw[i]->call (*iw[i]);
548	pcg	1.7	#endif
549
550	pcg	1.4	#elif IOM_TIME
551	pcg	1.5	if (!to)
552			break;
553
554	root	1.38	select (0, 0, 0, 0, to);
555	pcg	1.4	set_now ();
556	pcg	1.5	break;
557	pcg	1.4	#endif
558	pcg	1.5	}
559	pcg	1.1	}
560