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Comparing gvpe/src/iom.C (file contents):
Revision 1.20 by pcg, Fri Apr 2 14:42:45 2004 UTC vs.
Revision 1.22 by pcg, Thu Nov 11 17:41:55 2004 UTC

… …
15 You should have received a copy of the GNU General Public License 15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software 16 along with this program; if not, write to the Free Software
17 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 17 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/ 18*/
19 19
20#include "iom.h"
21
20#include <cstdio> 22#include <cstdio>
21#include <cstdlib> 23#include <cstdlib>
22#include <cerrno> 24#include <cerrno>
23 25
24#include <sys/time.h> 26#include <sys/time.h>
… …
26#include <assert.h> 28#include <assert.h>
27 29
28#if 1 // older unices need these includes for select (2) 30#if 1 // older unices need these includes for select (2)
29# include <unistd.h> 31# include <unistd.h>
30# include <sys/types.h> 32# include <sys/types.h>
33# include <time.h>
34#endif
35
36// for IOM_SIG
37#if IOM_SIG
38# include <signal.h>
39# include <fcntl.h>
31#endif 40#endif
32 41
33// if the BSDs would at least be marginally POSIX-compatible.. *sigh* 42// if the BSDs would at least be marginally POSIX-compatible.. *sigh*
34// until that happens, sys/select.h must come last 43// until that happens, sys/select.h must come last
35#include <sys/select.h> 44#include <sys/select.h>
36 45
37// for IOM_SIG
38#include <signal.h>
39
40#include "iom.h"
41
42// TSTAMP_MAX must still fit into a positive struct timeval 46// TSTAMP_MAX must still fit into a positive struct timeval
43#define TSTAMP_MAX (double)(1UL<<31) 47#define TSTAMP_MAX (double)(1UL<<31)
48
49#define TIMEVAL timeval
50#define TV_FRAC tv_usec
51#define TV_MULT 1000000L
52
53#if IOM_IO
54static io_manager_vec<io_watcher> iow;
55#endif
56#if IOM_CHECK
57static io_manager_vec<check_watcher> cw;
58#endif
59#if IOM_TIME
60static io_manager_vec<time_watcher> tw;
61#endif
62#if IOM_IDLE
63static io_manager_vec<idle_watcher> iw;
64#endif
65#if IOM_SIG
66static int sigpipe[2]; // signal signalling pipe
67static sigset_t sigs;
68struct sig_vec : io_manager_vec<sig_watcher> {
69 int pending;
70 sig_vec ()
71 : pending (false)
72 { }
73};
74static vector<sig_vec *> sw;
75#endif
44 76
45// this is a dummy time watcher to ensure that the first 77// this is a dummy time watcher to ensure that the first
46// time watcher is _always_ valid, this gets rid of a lot 78// time watcher is _always_ valid, this gets rid of a lot
47// of null-pointer-checks 79// of null-pointer-checks
48// (must come _before_ iom is being defined) 80// (must come _before_ iom is being defined)
… …
50 { 82 {
51 void cb (time_watcher &w) 83 void cb (time_watcher &w)
52 { 84 {
53 // should never get called 85 // should never get called
54 // reached end-of-time, or tstamp has a bogus definition, 86 // reached end-of-time, or tstamp has a bogus definition,
55 // or compiler initilization order broken, or somethine else :) 87 // or compiler initialisation order broken, or something else :)
56 abort (); 88 abort ();
57 } 89 }
58 90
59 tw0 () 91 tw0 ()
60 : time_watcher (this, &tw0::cb) 92 : time_watcher (this, &tw0::cb)
61 { } 93 { }
62 } tw0; 94 } tw0;
63 95
64tstamp NOW; 96tstamp NOW;
97
98#if IOM_TIME
99inline void set_now (void)
100{
101 struct timeval tv;
102
103 gettimeofday (&tv, 0);
104 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000.;
105}
106#endif
107
65static bool iom_valid; 108static bool iom_valid;
66io_manager iom; 109
110// used for initialisation only
111static struct init {
112 init ()
113 {
114#if IOM_SIG
115 sigemptyset (&sigs);
116
117 if (pipe (sigpipe))
118 {
119 perror ("io_manager: unable to create signal pipe, aborting.");
120 abort ();
121 }
122
123 fcntl (sigpipe[0], F_SETFL, O_NONBLOCK);
124 fcntl (sigpipe[1], F_SETFL, O_NONBLOCK);
125#endif
126
127 iom_valid = true;
128
129#if IOM_TIME
130 set_now ();
131
132 tw0.start (TSTAMP_MAX);
133#endif
134 }
135
136 static void required ();
137} init;
138
139void
140init::required ()
141{
142 if (!iom_valid)
143 {
144 write (2, "io_manager: early registration attempt, aborting.\n",
145 sizeof ("io_manager: early registration attempt, aborting.\n") - 1);
146 abort ();
147 }
148}
67 149
68template<class watcher> 150template<class watcher>
69void io_manager::reg (watcher *w, io_manager_vec<watcher> &queue) 151void io_manager::reg (watcher &w, io_manager_vec<watcher> &queue)
70{ 152{
71 if (!iom_valid) 153 init::required ();
72 abort ();
73 154
74 if (!w->active) 155 if (!w.active)
75 { 156 {
76#if IOM_CHECK
77 queue.activity = true;
78#endif
79 queue.push_back (w); 157 queue.push_back (&w);
80 w->active = queue.size (); 158 w.active = queue.size ();
81 } 159 }
82} 160}
83 161
84template<class watcher> 162template<class watcher>
85void io_manager::unreg (watcher *w, io_manager_vec<watcher> &queue) 163void io_manager::unreg (watcher &w, io_manager_vec<watcher> &queue)
86{ 164{
87 if (!iom_valid) 165 if (!iom_valid)
88 return; 166 return;
89 167
90 if (w->active) 168 if (w.active)
91 { 169 {
92 queue [w->active - 1] = 0; 170 queue [w.active - 1] = 0;
93 w->active = 0; 171 w.active = 0;
94 } 172 }
95} 173}
96 174
97#if IOM_TIME 175#if IOM_TIME
98void time_watcher::trigger () 176void time_watcher::trigger ()
99{ 177{
100 call (*this); 178 call (*this);
101 179 io_manager::reg (*this);
102 iom.reg (this);
103} 180}
104 181
105void io_manager::reg (time_watcher *w) { reg (w, tw); } 182void io_manager::reg (time_watcher &w) { io_manager::reg (w, tw); }
106void io_manager::unreg (time_watcher *w) { unreg (w, tw); } 183void io_manager::unreg (time_watcher &w) { io_manager::unreg (w, tw); }
107#endif 184#endif
108 185
109#if IOM_IO 186#if IOM_IO
110void io_manager::reg (io_watcher *w) { reg (w, iow); } 187void io_manager::reg (io_watcher &w) { io_manager::reg (w, iow); }
111void io_manager::unreg (io_watcher *w) { unreg (w, iow); } 188void io_manager::unreg (io_watcher &w) { io_manager::unreg (w, iow); }
112#endif 189#endif
113 190
114#if IOM_CHECK 191#if IOM_CHECK
115void io_manager::reg (check_watcher *w) { reg (w, cw); } 192void io_manager::reg (check_watcher &w) { io_manager::reg (w, cw); }
116void io_manager::unreg (check_watcher *w) { unreg (w, cw); } 193void io_manager::unreg (check_watcher &w) { io_manager::unreg (w, cw); }
117#endif 194#endif
118 195
119#if IOM_IDLE 196#if IOM_IDLE
120void io_manager::reg (idle_watcher *w) { reg (w, iw); } 197void io_manager::reg (idle_watcher &w) { io_manager::reg (w, iw); }
121void io_manager::unreg (idle_watcher *w) { unreg (w, iw); } 198void io_manager::unreg (idle_watcher &w) { io_manager::unreg (w, iw); }
122#endif
123
124#if IOM_TIME
125inline void set_now (void)
126{
127 struct timeval tv;
128
129 gettimeofday (&tv, 0);
130
131 NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
132}
133#endif 199#endif
134 200
135#if IOM_SIG 201#if IOM_SIG
136// race conditions galore 202static void
137 203sighandler (int signum)
138void io_manager::sighandler (int signum)
139{ 204{
140 assert (0 < signum && signum <= iom.sw.size ()); 205 sw [signum - 1]->pending = true;
141 206
142 sig_vec &sv = *iom.sw [signum - 1]; 207 // we use a pipe for signal notifications, as most current
143 208 // OSes (Linux...) do not implement pselect correctly. ugh.
144 for (int i = sv.size (); i--; ) 209 char ch = signum; // actual content not used
145 if (!sv[i]) 210 write (sigpipe[1], &ch, 1);
146 sv.erase_unordered (i);
147 else
148 sv[i]->call (*sv[i]);
149} 211}
150 212
151void io_manager::reg (sig_watcher *w) 213void io_manager::reg (sig_watcher &w)
152{ 214{
153 assert (0 < w->signum); 215 assert (0 < w.signum);
154 216
155 sw.reserve (w->signum); 217 sw.reserve (w.signum);
156 218
219 while (sw.size () < w.signum) // pathetic
220 sw.push_back (0);
221
157 sig_vec *&sv = sw [w->signum - 1]; 222 sig_vec *&sv = sw[w.signum - 1];
158 223
159 if (!sv) 224 if (!sv)
160 { 225 {
161 sv = new sig_vec; 226 sv = new sig_vec;
162 227
228 sigaddset (&sigs, w.signum);
229 sigprocmask (SIG_BLOCK, &sigs, NULL);
230
163 struct sigaction sa; 231 struct sigaction sa;
164 sa.sa_handler = io_manager::sighandler; 232 sa.sa_handler = sighandler;
165 sigfillset (&sa.sa_mask); 233 sigfillset (&sa.sa_mask);
166 sa.sa_flags = 0; 234 sa.sa_flags = SA_RESTART;
167 235
168 if (sigaction (w->signum, &sa, 0)) 236 if (sigaction (w.signum, &sa, 0))
169 { 237 {
170 perror ("Error while installing signal handler"); 238 perror ("io_manager: error while installing signal handler, ignoring.");
171 abort (); 239 abort ();
172 } 240 }
173 }
174 241
175 reg (w, *sv); 242 }
176}
177 243
244 io_manager::reg (w, *sv);
245}
246
178void io_manager::unreg (sig_watcher *w) 247void io_manager::unreg (sig_watcher &w)
179{ 248{
249 if (!w.active)
250 return;
251
180 assert (0 < w->signum && w->signum <= sw.size ()); 252 assert (0 < w.signum && w.signum <= sw.size ());
181 253
182 unreg (w, *sw [w->signum - 1]); 254 io_manager::unreg (w, *sw[w.signum - 1]);
183} 255}
184 256
185void sig_watcher::start (int signum) 257void sig_watcher::start (int signum)
186{ 258{
187 stop (); 259 stop ();
188 this->signum = signum; 260 this->signum = signum;
189 iom.reg (this); 261 io_manager::reg (*this);
190} 262}
191#endif 263#endif
192 264
193void io_manager::loop () 265void io_manager::loop ()
194{ 266{
267 init::required ();
268
195#if IOM_TIME 269#if IOM_TIME
196 set_now (); 270 set_now ();
197#endif 271#endif
198 272
199 for (;;) 273 for (;;)
200 { 274 {
201 struct timeval *to = 0;
202 struct timeval tval;
203 275
204#if IOM_IDLE 276#if IOM_TIME
205 if (iw.size ()) 277 // call pending time watchers
206 { 278 {
207 tval.tv_sec = 0; 279 bool activity;
208 tval.tv_usec = 0; 280
209 to = &tval;
210 } 281 do
211 else
212#endif
213
214 {
215#if IOM_TIME
216 time_watcher *next;
217
218 for (;;)
219 { 282 {
220 next = tw[0]; // the first time-watcher must exist at ALL times 283 activity = false;
221 284
222 for (int i = tw.size (); i--; ) 285 for (int i = tw.size (); i--; )
223 if (!tw[i]) 286 if (!tw[i])
224 tw.erase_unordered (i); 287 tw.erase_unordered (i);
225 else if (tw[i]->at < next->at) 288 else if (tw[i]->at <= NOW + IOM_ACCURACY)
226 next = tw[i];
227
228 if (next->at > NOW)
229 { 289 {
230 if (next != tw[0]) 290 time_watcher &w = *tw[i];
231 { 291
232 double diff = next->at - NOW;
233 tval.tv_sec = (int)diff;
234 tval.tv_usec = (int) ((diff - tval.tv_sec) * 1000000);
235 to = &tval;
236 }
237 break; 292 unreg (w);
293 w.call (w);
294
295 activity = true;
238 } 296 }
239 else
240 {
241 unreg (next);
242 next->call (*next);
243 }
244 } 297 }
245#endif 298 while (activity);
246
247 } 299 }
300#endif
248 301
249#if IOM_CHECK 302#if IOM_CHECK
250 tw.activity = false; 303 // call all check watchers
251
252 for (int i = cw.size (); i--; ) 304 for (int i = cw.size (); i--; )
253 if (!cw[i]) 305 if (!cw[i])
254 cw.erase_unordered (i); 306 cw.erase_unordered (i);
255 else 307 else
256 cw[i]->call (*cw[i]); 308 cw[i]->call (*cw[i]);
309#endif
257 310
258 if (tw.activity) 311 struct TIMEVAL *to = 0;
312 struct TIMEVAL tval;
313
314#if IOM_IDLE
315 if (iw.size ())
259 { 316 {
260 tval.tv_sec = 0; 317 tval.tv_sec = 0;
261 tval.tv_usec = 0; 318 tval.TV_FRAC = 0;
262 to = &tval; 319 to = &tval;
263 } 320 }
321 else
264#endif 322#endif
265 323 {
266#if IOM_IO 324#if IOM_TIME
325 // find earliest active watcher
326 time_watcher *next = tw[0]; // the first time-watcher must exist at ALL times
327
328 for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
329 if (*i && (*i)->at < next->at)
330 next = *i;
331
332 if (next->at > NOW && next != tw[0])
333 {
334 double diff = next->at - NOW;
335 tval.tv_sec = (int)diff;
336 tval.TV_FRAC = (int) ((diff - tval.tv_sec) * TV_MULT);
337 to = &tval;
338 }
339 }
340#endif
341
342#if IOM_IO || IOM_SIG
267 fd_set rfd, wfd; 343 fd_set rfd, wfd;
268 344
269 FD_ZERO (&rfd); 345 FD_ZERO (&rfd);
270 FD_ZERO (&wfd); 346 FD_ZERO (&wfd);
271 347
272 int fds = 0; 348 int fds = 0;
273 349
350# if IOM_IO
274 for (io_manager_vec<io_watcher>::iterator i = iow.end (); i-- > iow.begin (); ) 351 for (io_manager_vec<io_watcher>::const_iterator i = iow.end (); i-- > iow.begin (); )
275 if (*i) 352 if (*i)
276 { 353 {
277 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd); 354 if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
278 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd); 355 if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
279 356
280 if ((*i)->fd >= fds) fds = (*i)->fd + 1; 357 if ((*i)->fd >= fds) fds = (*i)->fd + 1;
281 } 358 }
359# endif
282 360
283 if (!to && !fds) //TODO: also check idle_watchers and check_watchers 361 if (!to && !fds) //TODO: also check idle_watchers and check_watchers?
284 break; // no events 362 break; // no events
285 363
364# if IOM_SIG
365 FD_SET (sigpipe[0], &rfd);
366 if (sigpipe[0] >= fds) fds = sigpipe[0] + 1;
367# endif
368
369# if IOM_SIG
370 // there is no race, as we use a pipe for signals, so select
371 // will return if a signal is caught.
372 sigprocmask (SIG_UNBLOCK, &sigs, NULL);
373# endif
286 fds = select (fds, &rfd, &wfd, NULL, to); 374 fds = select (fds, &rfd, &wfd, NULL, to);
375# if IOM_SIG
376 sigprocmask (SIG_BLOCK, &sigs, NULL);
377# endif
378
287# if IOM_TIME 379# if IOM_TIME
288 set_now (); 380 set_now ();
289# endif 381# endif
290 382
291 if (fds > 0) 383 if (fds > 0)
292 for (int i = iow.size (); i--; ) 384 {
293 if (!iow[i]) 385# if IOM_SIG
294 iow.erase_unordered (i); 386 if (FD_ISSET (sigpipe[0], &rfd))
295 else
296 { 387 {
297 short revents = iow[i]->events; 388 char ch;
298 389
299 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ; 390 while (read (sigpipe[0], &ch, 1) > 0)
300 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE; 391 ;
301 392
302 if (revents) 393 for (sig_vec **svp = sw.end (); svp-- > sw.begin (); )
303 iow[i]->call (*iow[i], revents); 394 if (*svp && (*svp)->pending)
395 {
396 sig_vec &sv = **svp;
397 for (int i = sv.size (); i--; )
398 if (!sv[i])
399 sv.erase_unordered (i);
400 else
401 sv[i]->call (*sv[i]);
402
403 sv.pending = false;
404 }
304 } 405 }
406# endif
407
408# if IOM_IO
409 for (int i = iow.size (); i--; )
410 if (!iow[i])
411 iow.erase_unordered (i);
412 else
413 {
414 short revents = iow[i]->events;
415
416 if (!FD_ISSET (iow[i]->fd, &rfd)) revents &= ~EVENT_READ;
417 if (!FD_ISSET (iow[i]->fd, &wfd)) revents &= ~EVENT_WRITE;
418
419 if (revents)
420 iow[i]->call (*iow[i], revents);
421 }
422#endif
423 }
305 else if (fds < 0 && errno != EINTR) 424 else if (fds < 0 && errno != EINTR)
306 { 425 {
307 perror ("Error while waiting for I/O or time event"); 426 perror ("io_manager: fatal error while waiting for I/O or time event, aborting.");
308 abort (); 427 abort ();
309 } 428 }
310#if IOM_IDLE 429#if IOM_IDLE
311 else 430 else
312 for (int i = iw.size (); i--; ) 431 for (int i = iw.size (); i--; )
… …
323 select (0, 0, 0, 0, &to); 442 select (0, 0, 0, 0, &to);
324 set_now (); 443 set_now ();
325#else 444#else
326 break; 445 break;
327#endif 446#endif
328
329 } 447 }
330} 448}
331 449
332io_manager::io_manager ()
333{
334 iom_valid = true;
335
336#if IOM_TIME
337 set_now ();
338
339 tw0.start (TSTAMP_MAX);
340#endif
341}
342
343io_manager::~io_manager ()
344{
345 iom_valid = false;
346}
347

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