libratbox/src/kqueue.c

   1 /*
   2  *  ircd-ratbox: A slightly useful ircd.
   3  *  kqueue.c: FreeBSD kqueue compatible network routines.
   4  *
   5  *  Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
   6  *  Copyright (C) 1996-2002 Hybrid Development Team
   7  *  Copyright (C) 2001 Adrian Chadd <adrian@creative.net.au>
   8  *  Copyright (C) 2002-2005 ircd-ratbox development team
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or
  13  *  (at your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful,
  16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  *  GNU General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License
  21  *  along with this program; if not, write to the Free Software
  22  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
  23  *  USA
  24  *
  25  *  $Id: kqueue.c 25364 2008-05-14 17:55:22Z jilles $
  26  */
  27
  28 #include <libratbox_config.h>
  29 #include <ratbox_lib.h>
  30 #include <commio-int.h>
  31 #include <event-int.h>
  32
  33 #if defined(HAVE_SYS_EVENT_H) && (HAVE_KEVENT)
  34
  35 #include <sys/event.h>
  36
  37 /* jlemon goofed up and didn't add EV_SET until fbsd 4.3 */
  38
  39 #ifndef EV_SET
  40 #define EV_SET(kevp, a, b, c, d, e, f) do {     \
  41         (kevp)->ident = (a);                    \
  42         (kevp)->filter = (b);                   \
  43         (kevp)->flags = (c);                    \
  44         (kevp)->fflags = (d);                   \
  45         (kevp)->data = (e);                     \
  46         (kevp)->udata = (f);                    \
  47 } while(0)
  48 #endif
  49
  50 #ifdef EVFILT_TIMER
  51 #define KQUEUE_SCHED_EVENT
  52 #endif
  53
  54
  55 static void kq_update_events(rb_fde_t *, short, PF *);
  56 static int kq;
  57 static struct timespec zero_timespec;
  58
  59 static struct kevent *kqlst;    /* kevent buffer */
  60 static struct kevent *kqout;    /* kevent output buffer */
  61 static int kqmax;               /* max structs to buffer */
  62 static int kqoff;               /* offset into the buffer */
  63
  64
  65 int
  66 rb_setup_fd_kqueue(rb_fde_t * F)
  67 {
  68         return 0;
  69 }
  70
  71 static void
  72 kq_update_events(rb_fde_t * F, short filter, PF * handler)
  73 {
  74         PF *cur_handler;
  75         int kep_flags;
  76
  77         switch (filter)
  78         {
  79         case EVFILT_READ:
  80                 cur_handler = F->read_handler;
  81                 break;
  82         case EVFILT_WRITE:
  83                 cur_handler = F->write_handler;
  84                 break;
  85         default:
  86                 /* XXX bad! -- adrian */
  87                 return;
  88                 break;
  89         }
  90
  91         if((cur_handler == NULL && handler != NULL) || (cur_handler != NULL && handler == NULL))
  92         {
  93                 struct kevent *kep;
  94
  95                 kep = kqlst + kqoff;
  96
  97                 if(handler != NULL)
  98                 {
  99                         kep_flags = EV_ADD | EV_ONESHOT;
 100                 }
 101                 else
 102                 {
 103                         kep_flags = EV_DELETE;
 104                 }
 105
 106                 EV_SET(kep, (uintptr_t) F->fd, filter, kep_flags, 0, 0, (void *) F);
 107
 108                 if(++kqoff == kqmax)
 109                 {
 110                         int ret, i;
 111
 112                         /* Add them one at a time, because there may be
 113                          * already closed fds in it. The kernel will try
 114                          * to report invalid fds in the output; if there
 115                          * is no space, it silently stops processing the
 116                          * array at that point. We cannot give output space
 117                          * because that would also return events we cannot
 118                          * process at this point.
 119                          */
 120                         for (i = 0; i < kqoff; i++)
 121                         {
 122                                 ret = kevent(kq, kqlst + i, 1, NULL, 0, &zero_timespec);
 123                                 /* jdc -- someone needs to do error checking... */
 124                                 /* EBADF is normal here -- jilles */
 125                                 if(ret == -1 && errno != EBADF)
 126                                         rb_lib_log("kq_update_events(): kevent(): %s", strerror(errno));
 127                         }
 128                         kqoff = 0;
 129                 }
 130         }
 131 }
 132
 133
 134
 135 /* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
 136 /* Public functions */
 137
 138
 139 /*
 140  * rb_init_netio
 141  *
 142  * This is a needed exported function which will be called to initialise
 143  * the network loop code.
 144  */
 145 int
 146 rb_init_netio_kqueue(void)
 147 {
 148         kq = kqueue();
 149         if(kq < 0)
 150         {
 151                 return errno;
 152         }
 153         kqmax = getdtablesize();
 154         kqlst = rb_malloc(sizeof(struct kevent) * kqmax);
 155         kqout = rb_malloc(sizeof(struct kevent) * kqmax);
 156         rb_open(kq, RB_FD_UNKNOWN, "kqueue fd");
 157         zero_timespec.tv_sec = 0;
 158         zero_timespec.tv_nsec = 0;
 159
 160         return 0;
 161 }
 162
 163 /*
 164  * rb_setselect
 165  *
 166  * This is a needed exported function which will be called to register
 167  * and deregister interest in a pending IO state for a given FD.
 168  */
 169 void
 170 rb_setselect_kqueue(rb_fde_t * F, unsigned int type, PF * handler, void *client_data)
 171 {
 172         lrb_assert(IsFDOpen(F));
 173
 174         if(type & RB_SELECT_READ)
 175         {
 176                 kq_update_events(F, EVFILT_READ, handler);
 177                 F->read_handler = handler;
 178                 F->read_data = client_data;
 179         }
 180         if(type & RB_SELECT_WRITE)
 181         {
 182                 kq_update_events(F, EVFILT_WRITE, handler);
 183                 F->write_handler = handler;
 184                 F->write_data = client_data;
 185         }
 186 }
 187
 188 /*
 189  * Check all connections for new connections and input data that is to be
 190  * processed. Also check for connections with data queued and whether we can
 191  * write it out.
 192  */
 193
 194 /*
 195  * rb_select
 196  *
 197  * Called to do the new-style IO, courtesy of squid (like most of this
 198  * new IO code). This routine handles the stuff we've hidden in
 199  * rb_setselect and fd_table[] and calls callbacks for IO ready
 200  * events.
 201  */
 202
 203 int
 204 rb_select_kqueue(long delay)
 205 {
 206         int num, i;
 207         struct timespec poll_time;
 208         struct timespec *pt;
 209         rb_fde_t *F;
 210
 211
 212         if(delay < 0) {
 213                 pt = NULL;
 214         }
 215         else {
 216                 pt = &poll_time;
 217                 poll_time.tv_sec = delay / 1000;
 218                 poll_time.tv_nsec = (delay % 1000) * 1000000;
 219         }
 220
 221         for (;;)
 222         {
 223                 num = kevent(kq, kqlst, kqoff, kqout, kqmax, pt);
 224                 kqoff = 0;
 225
 226                 if(num >= 0)
 227                         break;
 228
 229                 if(rb_ignore_errno(errno))
 230                         break;
 231
 232                 rb_set_time();
 233
 234                 return RB_ERROR;
 235
 236                 /* NOTREACHED */
 237         }
 238
 239         rb_set_time();
 240
 241         if(num == 0)
 242                 return RB_OK;   /* No error.. */
 243
 244         for (i = 0; i < num; i++)
 245         {
 246                 PF *hdl = NULL;
 247
 248                 if(kqout[i].flags & EV_ERROR)
 249                 {
 250                         errno = kqout[i].data;
 251                         /* XXX error == bad! -- adrian */
 252                         continue;       /* XXX! */
 253                 }
 254
 255                 switch (kqout[i].filter)
 256                 {
 257
 258                 case EVFILT_READ:
 259                         F = kqout[i].udata;
 260                         if((hdl = F->read_handler) != NULL)
 261                         {
 262                                 F->read_handler = NULL;
 263                                 hdl(F, F->read_data);
 264                         }
 265
 266                         break;
 267
 268                 case EVFILT_WRITE:
 269                         F = kqout[i].udata;
 270                         if((hdl = F->write_handler) != NULL)
 271                         {
 272                                 F->write_handler = NULL;
 273                                 hdl(F, F->write_data);
 274                         }
 275                         break;
 276 #if defined(EVFILT_TIMER)
 277                 case EVFILT_TIMER:
 278                         rb_run_event(kqout[i].udata);
 279                         break;
 280 #endif
 281                 default:
 282                         /* Bad! -- adrian */
 283                         break;
 284                 }
 285         }
 286         return RB_OK;
 287 }
 288
 289 #if defined(KQUEUE_SCHED_EVENT)
 290 static int can_do_event = 0;
 291 int
 292 rb_kqueue_supports_event(void)
 293 {
 294         struct kevent kv;
 295         struct timespec ts;
 296         int xkq;
 297
 298         if(can_do_event == 1)
 299                 return 1;
 300         if(can_do_event == -1)
 301                 return 0;
 302
 303         xkq = kqueue();
 304         ts.tv_sec = 0;
 305         ts.tv_nsec = 1000;
 306
 307
 308         EV_SET(&kv, (uintptr_t) 0x0, EVFILT_TIMER, EV_ADD | EV_ONESHOT, 0, 1, 0);
 309         if(kevent(xkq, &kv, 1, NULL, 0, NULL) < 0)
 310         {
 311                 can_do_event = -1;
 312                 close(xkq);
 313                 return 0;
 314         }
 315         close(xkq);
 316         can_do_event = 1;
 317         return 1;
 318 }
 319
 320 int
 321 rb_kqueue_sched_event(struct ev_entry *event, int when)
 322 {
 323         struct kevent kev;
 324         int kep_flags;
 325
 326         kep_flags = EV_ADD;
 327         if(event->frequency == 0)
 328                 kep_flags |= EV_ONESHOT;
 329         EV_SET(&kev, (uintptr_t) event, EVFILT_TIMER, kep_flags, 0, when * 1000, event);
 330         if(kevent(kq, &kev, 1, NULL, 0, NULL) < 0)
 331                 return 0;
 332         return 1;
 333 }
 334
 335 void
 336 rb_kqueue_unsched_event(struct ev_entry *event)
 337 {
 338         struct kevent kev;
 339         EV_SET(&kev, (uintptr_t) event, EVFILT_TIMER, EV_DELETE, 0, 0, event);
 340         kevent(kq, &kev, 1, NULL, 0, NULL);
 341 }
 342
 343 void
 344 rb_kqueue_init_event(void)
 345 {
 346         return;
 347 }
 348 #endif /* KQUEUE_SCHED_EVENT */
 349
 350 #else /* kqueue not supported */
 351 int
 352 rb_init_netio_kqueue(void)
 353 {
 354         errno = ENOSYS;
 355         return -1;
 356 }
 357
 358 void
 359 rb_setselect_kqueue(rb_fde_t * F, unsigned int type, PF * handler, void *client_data)
 360 {
 361         errno = ENOSYS;
 362         return;
 363 }
 364
 365 int
 366 rb_select_kqueue(long delay)
 367 {
 368         errno = ENOSYS;
 369         return -1;
 370 }
 371
 372 int
 373 rb_setup_fd_kqueue(rb_fde_t * F)
 374 {
 375         errno = ENOSYS;
 376         return -1;
 377 }
 378
 379 #endif
 380
 381 #if !defined(HAVE_KEVENT) || !defined(KQUEUE_SCHED_EVENT)
 382 void
 383 rb_kqueue_init_event(void)
 384 {
 385         return;
 386 }
 387
 388 int
 389 rb_kqueue_sched_event(struct ev_entry *event, int when)
 390 {
 391         errno = ENOSYS;
 392         return -1;
 393 }
 394
 395 void
 396 rb_kqueue_unsched_event(struct ev_entry *event)
 397 {
 398         return;
 399 }
 400
 401 int
 402 rb_kqueue_supports_event(void)
 403 {
 404         errno = ENOSYS;
 405         return 0;
 406 }
 407 #endif /* !HAVE_KEVENT || !KQUEUE_SCHED_EVENT */