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Comparing rxvt-unicode/src/iom.C (file contents):
Revision 1.1 by pcg, Mon Nov 24 17:28:08 2003 UTC vs.
Revision 1.33 by root, Thu Jan 19 09:47:15 2006 UTC

1/* 1/*
2 iom.C -- generic I/O multiplexor 2 iom.C -- generic I/O multiplexer
3 Copyright (C) 2003 Marc Lehmann <pcg@goof.com> 3 Copyright (C) 2003, 2004 Marc Lehmann <gvpe@schmorp.de>
4 4
5 This file is part of GVPE.
6
5 This program is free software; you can redistribute it and/or modify 7 GVPE is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by 8 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or 9 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version. 10 (at your option) any later version.
9 11
10 This program is distributed in the hope that it will be useful, 12 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details. 15 GNU General Public License for more details.
14 16
15 You should have received a copy of the GNU General Public License 17 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software 18 along with gvpe; if not, write to the Free Software
17 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18*/ 20*/
19 21
20#include "../config.h" 22#include "iom.h"
21 23
22#include <cstdio> 24#include <cstdio>
25#include <cstdlib>
26#include <cerrno>
27#include <cassert>
23 28
29#include <sys/types.h>
30#include <sys/time.h>
31
32#if 1 // older unices need these includes for select (2)
33# include <unistd.h>
34# include <time.h>
35#endif
36
37#if IOM_CHILD
38# include <sys/wait.h>
39#endif
40
41#if IOM_SIG
42# include <csignal>
43# include <fcntl.h>
44#endif
45
46// if the BSDs would at least be marginally POSIX-compatible.. *sigh*
47// until that happens, sys/select.h must come last
24#include <sys/select.h> 48#include <sys/select.h>
25#include <sys/time.h>
26 49
27#include "iom.h" 50#define TIMEVAL timeval
51#define TV_FRAC tv_usec
52#define TV_MULT 1000000L
53
54#if IOM_IO
55static io_manager_vec<io_watcher> iow;
56#endif
57#if IOM_CHECK
58static io_manager_vec<check_watcher> cw;
59#endif
60#if IOM_TIME
61static io_manager_vec<time_watcher> tw;
62#endif
63#if IOM_IDLE
64static io_manager_vec<idle_watcher> iw;
65#endif
66#if IOM_SIG
67static int sigpipe[2]; // signal signalling pipe
68static sigset_t sigs;
69struct sig_vec : io_manager_vec<sig_watcher> {
70 int pending;
71 sig_vec ()
72 : pending (false)
73 { }
74};
75static vector<sig_vec *> sw;
76#endif
77#if IOM_CHILD
78static io_manager_vec<child_watcher> pw;
79#endif
80
81// this is a dummy time watcher to ensure that the first
82// time watcher is _always_ valid, this gets rid of a lot
83// of null-pointer-checks
84// (must come _before_ iom is being defined)
85static struct tw0 : time_watcher
86{
87 void cb (time_watcher &w)
88 {
89 // should never get called
90 // reached end-of-time, or tstamp has a bogus definition,
91 // or compiler initialisation order broken, or something else :)
92 abort ();
93 }
94
95 tw0 ()
96 : time_watcher (this, &tw0::cb)
97 { }
98} tw0;
28 99
29tstamp NOW; 100tstamp NOW;
101
102#if IOM_CHILD
103// sig_watcher for child signal(s)
104static struct sw0 : sig_watcher
105{
106 void cb (sig_watcher &w)
107 {
108 // SIGCHLD, call corresponding watchera
109 pid_t pid;
110 int status;
111
112 while ((pid = waitpid (-1, &status, WNOHANG)) > 0)
113 for (int i = pw.size (); i--; )
114 {
115 child_watcher *w = pw[i];
116
117 if (!w)
118 pw.erase_unordered (i);
119 else if (w->pid == pid)
120 {
121 w->stop ();
122 w->call (*w, status);
123 }
124 }
125
126 }
127
128 sw0 ()
129 : sig_watcher (this, &sw0::cb)
130 { }
131} sw0;
132#endif
133
134#if IOM_TIME
135tstamp io_manager::now ()
136{
137 struct timeval tv;
138
139 gettimeofday (&tv, 0);
140 return (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000.;
141}
142
143void io_manager::set_now ()
144{
145 NOW = now ();
146}
147#endif
148
30bool iom_valid; 149static bool iom_valid;
31io_manager iom;
32 150
151// used for initialisation only
152static struct init {
153 init ()
154 {
155 iom_valid = true;
156
157#if IOM_SIG
158 sigemptyset (&sigs);
159
160 if (pipe (sigpipe))
161 {
162 perror ("io_manager: unable to create signal pipe, aborting.");
163 abort ();
164 }
165
166 fcntl (sigpipe[0], F_SETFL, O_NONBLOCK); fcntl (sigpipe[0], F_SETFD, FD_CLOEXEC);
167 fcntl (sigpipe[1], F_SETFL, O_NONBLOCK); fcntl (sigpipe[1], F_SETFD, FD_CLOEXEC);
168#endif
169
170#if IOM_CHILD
171 sw0.start (SIGCHLD);
172#endif
173
174#if IOM_TIME
175 io_manager::set_now ();
176
177 tw0.start (TSTAMP_MAX);
178#endif
179 }
180
181 ~init ()
182 {
183 iom_valid = false;
184 }
185
186 static void required ();
187} init;
188
189void
190init::required ()
191{
192 if (!iom_valid)
193 {
194 write (2, "io_manager: early registration attempt, aborting.\n",
195 sizeof ("io_manager: early registration attempt, aborting.\n") - 1);
196 abort ();
197 }
198}
199
200template<class watcher>
201void io_manager::reg (watcher &w, io_manager_vec<watcher> &queue)
202{
203 init::required ();
204
205 if (!w.active)
206 {
207 queue.push_back (&w);
208 w.active = queue.size ();
209 }
210}
211
212template<class watcher>
213void io_manager::unreg (watcher &w, io_manager_vec<watcher> &queue)
214{
215 if (!iom_valid)
216 return;
217
218 if (w.active)
219 {
220 queue [w.active - 1] = 0;
221 w.active = 0;
222 }
223}
224
225#if IOM_TIME
33void time_watcher::trigger () 226void time_watcher::trigger ()
34{ 227{
35 call (*this); 228 call (*this);
36 229 io_manager::reg (*this);
37 iom.reg (this);
38} 230}
39 231
40time_watcher::~time_watcher () 232void io_manager::reg (time_watcher &w) { io_manager::reg (w, tw); }
41{ 233void io_manager::unreg (time_watcher &w) { io_manager::unreg (w, tw); }
42 if (iom_valid) 234#endif
43 iom.unreg (this);
44}
45 235
46io_watcher::~io_watcher () 236#if IOM_IO
47{ 237void io_manager::reg (io_watcher &w) { io_manager::reg (w, iow); }
48 if (iom_valid) 238void io_manager::unreg (io_watcher &w) { io_manager::unreg (w, iow); }
49 iom.unreg (this); 239#endif
50}
51 240
241#if IOM_CHECK
242void io_manager::reg (check_watcher &w) { io_manager::reg (w, cw); }
243void io_manager::unreg (check_watcher &w) { io_manager::unreg (w, cw); }
244#endif
245
246#if IOM_IDLE
247void io_manager::reg (idle_watcher &w) { io_manager::reg (w, iw); }
248void io_manager::unreg (idle_watcher &w) { io_manager::unreg (w, iw); }
249#endif
250
251#if IOM_SIG
252static void
253sighandler (int signum)
254{
255 sw [signum - 1]->pending = true;
256
257 // we use a pipe for signal notifications, as most current
258 // OSes (Linux...) do not implement pselect correctly. ugh.
259 char ch = signum; // actual content not used
260 write (sigpipe[1], &ch, 1);
261}
262
52void io_manager::reg (io_watcher *w) 263void io_manager::reg (sig_watcher &w)
53{ 264{
54 if (find (iow.begin (), iow.end (), w) == iow.end ()) 265 init::required ();
266
267 assert (0 < w.signum);
268
269 sw.reserve (w.signum);
270
271 while (sw.size () < w.signum) // pathetic
55 iow.push_back (w); 272 sw.push_back (0);
56}
57 273
274 sig_vec *&sv = sw[w.signum - 1];
275
276 if (!sv)
277 {
278 sv = new sig_vec;
279
280 sigaddset (&sigs, w.signum);
281 sigprocmask (SIG_BLOCK, &sigs, NULL);
282
283 struct sigaction sa;
284 sa.sa_handler = sighandler;
285 sigfillset (&sa.sa_mask);
286 sa.sa_flags = SA_RESTART;
287
288 if (sigaction (w.signum, &sa, 0))
289 {
290 perror ("io_manager: error while installing signal handler, ignoring.");
291 abort ();
292 }
293
294 }
295
296 io_manager::reg (w, *sv);
297}
298
58void io_manager::unreg (io_watcher *w) 299void io_manager::unreg (sig_watcher &w)
59{ 300{
60 iow.erase (find (iow.begin (), iow.end (), w)); 301 if (!w.active || !iom_valid)
61} 302 return;
62 303
63void io_manager::reg (time_watcher *w) 304 assert (0 < w.signum && w.signum <= sw.size ());
64{ 305
65 if (find (tw.begin (), tw.end (), w) == tw.end ()) 306 io_manager::unreg (w, *sw[w.signum - 1]);
66 tw.push_back (w);
67} 307}
68 308
69void io_manager::unreg (time_watcher *w) 309void sig_watcher::start (int signum)
70{ 310{
71 tw.erase (find (tw.begin (), tw.end (), w)); 311 stop ();
312 this->signum = signum;
313 io_manager::reg (*this);
72} 314}
315#endif
73 316
74inline void set_now (void) 317#if IOM_CHILD
75{ 318void io_manager::reg (child_watcher &w) { io_manager::reg (w, pw); }
76 struct timeval tv; 319void io_manager::unreg (child_watcher &w) { io_manager::unreg (w, pw); }
77 320#endif
78 gettimeofday (&tv, 0);
79
80 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
81}
82 321
83void io_manager::loop () 322void io_manager::loop ()
84{ 323{
324 init::required ();
325
326#if IOM_TIME
85 set_now (); 327 set_now ();
328#endif
86 329
87 for (;;) 330 for (;;)
88 { 331 {
89 time_watcher *w;
90 332
91 for (;;) 333#if IOM_TIME
334 // call pending time watchers
335 {
336 bool activity;
337
338 do
339 {
340 activity = false;
341
342 for (int i = tw.size (); i--; )
343 if (!tw[i])
344 tw.erase_unordered (i);
345 else if (tw[i]->at <= NOW)
346 {
347 time_watcher &w = *tw[i];
348
349 unreg (w);
350 w.call (w);
351
352 activity = true;
353 }
354 }
355 while (activity);
356 }
357#endif
358
359#if IOM_CHECK
360 // call all check watchers
361 for (int i = cw.size (); i--; )
362 if (!cw[i])
363 cw.erase_unordered (i);
364 else
365 cw[i]->call (*cw[i]);
366#endif
367
368 struct TIMEVAL *to = 0;
369 struct TIMEVAL tval;
370
371#if IOM_IDLE
372 if (iw.size ())
92 { 373 {
93 w = tw[0]; 374 tval.tv_sec = 0;
94 375 tval.TV_FRAC = 0;
95 for (time_watcher **i = tw.begin (); i != tw.end (); ++i) 376 to = &tval;
96 if ((*i)->at < w->at)
97 w = *i;
98
99 if (w->at > NOW)
100 break;
101
102 // call it
103 w->call (*w);
104
105 // re-add it if necessary
106 if (w->at >= 0)
107 reg (w);
108 } 377 }
378 else
379#endif
380 {
381#if IOM_TIME
382 // find earliest active watcher
383 time_watcher *next = tw[0]; // the first time-watcher must exist at ALL times
109 384
110 struct timeval to; 385 for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
386 if (*i && (*i)->at < next->at)
387 next = *i;
388
389 if (next->at > NOW && next != tw[0])
390 {
111 double diff = w->at - NOW; 391 double diff = next->at - NOW;
112 to.tv_sec = (int)diff; 392 tval.tv_sec = (int)diff;
113 to.tv_usec = (int)((diff - to.tv_sec) * 1000000); 393 tval.TV_FRAC = (int) ((diff - tval.tv_sec) * TV_MULT);
394 to = &tval;
395 }
396 }
397#endif
114 398
399#if IOM_IO || IOM_SIG
115 fd_set rfd, wfd; 400 fd_set rfd, wfd;
116 401
117 FD_ZERO (&rfd); 402 FD_ZERO (&rfd);
118 FD_ZERO (&wfd); 403 FD_ZERO (&wfd);
119 404
120 int fds = 0; 405 int fds = 0;
121 406
122 for (io_watcher **w = iow.begin (); w < iow.end (); ++w) 407# if IOM_IO
408 for (io_manager_vec<io_watcher>::const_iterator i = iow.end (); i-- > iow.begin (); )
409 if (*i)
123 { 410 {
124 if ((*w)->events & EVENT_READ ) FD_SET ((*w)->fd, &rfd); 411 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
125 if ((*w)->events & EVENT_WRITE) FD_SET ((*w)->fd, &wfd); 412 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
126 413
127 if ((*w)->fd > fds) fds = (*w)->fd; 414 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
128 } 415 }
416# endif
129 417
418 if (!to && !fds) //TODO: also check idle_watchers and check_watchers?
419 break; // no events
420
421# if IOM_SIG
422 FD_SET (sigpipe[0], &rfd);
423 if (sigpipe[0] >= fds) fds = sigpipe[0] + 1;
424# endif
425
426# if IOM_SIG
427 // there is no race, as we use a pipe for signals, so select
428 // will return if a signal is caught.
429 sigprocmask (SIG_UNBLOCK, &sigs, NULL);
430# endif
130 fds = select (fds + 1, &rfd, &wfd, 0, &to); 431 fds = select (fds, &rfd, &wfd, NULL, to);
432# if IOM_SIG
433 sigprocmask (SIG_BLOCK, &sigs, NULL);
434# endif
131 435
436# if IOM_TIME
437 {
438 // update time, try to compensate for gross non-monotonic time changes
439 tstamp diff = NOW;
440 set_now ();
441 diff = NOW - diff;
442
443 if (diff < 0)
444 for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
445 if (*i)
446 (*i)->at += diff;
447 }
448# endif
449
450 if (fds > 0)
451 {
452# if IOM_SIG
453 if (FD_ISSET (sigpipe[0], &rfd))
454 {
455 char ch;
456
457 while (read (sigpipe[0], &ch, 1) > 0)
458 ;
459
460 for (vector<sig_vec *>::iterator svp = sw.end (); svp-- > sw.begin (); )
461 if (*svp && (*svp)->pending)
462 {
463 sig_vec &sv = **svp;
464 for (int i = sv.size (); i--; )
465 if (!sv[i])
466 sv.erase_unordered (i);
467 else
468 sv[i]->call (*sv[i]);
469
470 sv.pending = false;
471 }
472 }
473# endif
474
475# if IOM_IO
476 for (int i = iow.size (); i--; )
477 if (!iow[i])
478 iow.erase_unordered (i);
479 else
480 {
481 io_watcher &w = *iow[i];
482 short revents = w.events;
483
484 if (!FD_ISSET (w.fd, &rfd)) revents &= ~EVENT_READ;
485 if (!FD_ISSET (w.fd, &wfd)) revents &= ~EVENT_WRITE;
486
487 if (revents)
488 w.call (w, revents);
489 }
490#endif
491 }
492 else if (fds < 0 && errno != EINTR)
493 {
494 perror ("io_manager: fatal error while waiting for I/O or time event, aborting.");
495 abort ();
496 }
497#if IOM_IDLE
498 else
499 for (int i = iw.size (); i--; )
500 if (!iw[i])
501 iw.erase_unordered (i);
502 else
503 iw[i]->call (*iw[i]);
504#endif
505
506#elif IOM_TIME
507 if (!to)
508 break;
509
510 select (0, 0, 0, 0, &to);
132 set_now (); 511 set_now ();
133 512#else
134 if (fds > 0) 513 break;
135 for (io_watcher **w = iow.begin (); w < iow.end (); w++) 514#endif
136 {
137 short revents = (*w)->events;
138
139 if (!FD_ISSET ((*w)->fd, &rfd)) revents &= ~EVENT_READ;
140 if (!FD_ISSET ((*w)->fd, &wfd)) revents &= ~EVENT_WRITE;
141
142 if (revents)
143 (*w)->call (**w, revents);
144 }
145 } 515 }
146} 516}
147 517
148void io_manager::idle_cb (time_watcher &w)
149{
150 w.at = NOW + 1000000000;
151}
152
153io_manager::io_manager ()
154{
155 set_now ();
156
157 iom_valid = true;
158
159 idle = new time_watcher (this, &io_manager::idle_cb);
160 idle->start (0);
161}
162
163io_manager::~io_manager ()
164{
165 iom_valid = false;
166}
167

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