libseven/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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  23  *  USA
  24  *
  25  *  $Id: kqueue.c 181 2006-12-18 02:56:07Z beu $
  26  */
  27
  28 #include "stdinc.h"
  29 #include <sys/event.h>
  30
  31 #include "libseven.h"
  32
  33 #define KE_LENGTH MAX_CLIENTS
  34
  35 /* jlemon goofed up and didn't add EV_SET until fbsd 4.3 */
  36
  37 #ifndef EV_SET
  38 #define EV_SET(kevp, a, b, c, d, e, f) do {     \
  39         (kevp)->ident = (a);                    \
  40         (kevp)->filter = (b);                   \
  41         (kevp)->flags = (c);                    \
  42         (kevp)->fflags = (d);                   \
  43         (kevp)->data = (e);                     \
  44         (kevp)->udata = (f);                    \
  45 } while(0)
  46 #endif
  47
  48 static void kq_update_events(fde_t *, short, PF *);
  49 static int kq;
  50 static struct timespec zero_timespec;
  51
  52 static struct kevent *kqlst;    /* kevent buffer */
  53 static int kqmax;               /* max structs to buffer */
  54 static int kqoff;               /* offset into the buffer */
  55
  56
  57 /* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
  58 /* Private functions */
  59
  60 void
  61 kq_update_events(fde_t * F, short filter, PF * handler)
  62 {
  63         PF *cur_handler;
  64         int kep_flags;
  65
  66         switch (filter)
  67         {
  68         case EVFILT_READ:
  69                 cur_handler = F->read_handler;
  70                 break;
  71         case EVFILT_WRITE:
  72                 cur_handler = F->write_handler;
  73                 break;
  74         default:
  75                 /* XXX bad! -- adrian */
  76                 return;
  77                 break;
  78         }
  79
  80         if((cur_handler == NULL && handler != NULL) || (cur_handler != NULL && handler == NULL))
  81         {
  82                 struct kevent *kep;
  83
  84                 kep = kqlst + kqoff;
  85
  86                 if(handler != NULL)
  87                 {
  88                         if(filter == EVFILT_WRITE)
  89                                 kep_flags = (EV_ADD | EV_ENABLE | EV_ONESHOT);
  90                         else
  91                                 kep_flags = (EV_ADD | EV_ENABLE);
  92                 }
  93                 else
  94                 {
  95                         /* lets definately not poll stuff that isn't real --
  96                          * some kqueue implementations hate doing this... and
  97                          * it's intended to delete AND disable at the same time.
  98                          *
  99                          * don't believe me? read kevent(4). --nenolod
 100                          */
 101                         kep_flags = (EV_DELETE | EV_DISABLE);
 102                 }
 103
 104                 EV_SET(kep, (uintptr_t) F->fd, filter, kep_flags, 0, 0, (void *) F);
 105
 106                 if(kqoff == kqmax)
 107                 {
 108                         int ret;
 109
 110                         ret = kevent(kq, kqlst, kqoff, NULL, 0, &zero_timespec);
 111                         /* jdc -- someone needs to do error checking... */
 112                         if(ret == -1)
 113                         {
 114                                 libseven_log("kq_update_events(): kevent(): %s", strerror(errno));
 115                                 return;
 116                         }
 117                         kqoff = 0;
 118                 }
 119                 else
 120                 {
 121                         kqoff++;
 122                 }
 123         }
 124 }
 125
 126
 127
 128 /* XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */
 129 /* Public functions */
 130
 131
 132 /*
 133  * init_netio
 134  *
 135  * This is a needed exported function which will be called to initialise
 136  * the network loop code.
 137  */
 138 void
 139 init_netio(void)
 140 {
 141         kq = kqueue();
 142         if(kq < 0)
 143         {
 144                 libseven_log("init_netio: Couldn't open kqueue fd!\n");
 145                 exit(115);      /* Whee! */
 146         }
 147         kqmax = getdtablesize();
 148         kqlst = MyMalloc(sizeof(struct kevent) * kqmax);
 149         zero_timespec.tv_sec = 0;
 150         zero_timespec.tv_nsec = 0;
 151 }
 152
 153 /*
 154  * comm_setselect
 155  *
 156  * This is a needed exported function which will be called to register
 157  * and deregister interest in a pending IO state for a given FD.
 158  */
 159 void
 160 comm_setselect(int fd, fdlist_t list, unsigned int type, PF * handler,
 161                void *client_data, time_t timeout)
 162 {
 163         fde_t *F = &fd_table[fd];
 164         s_assert(fd >= 0);
 165         s_assert(F->flags.open);
 166
 167         /* Update the list, even though we're not using it .. */
 168         F->list = list;
 169
 170         if(type & COMM_SELECT_READ)
 171         {
 172                 kq_update_events(F, EVFILT_READ, handler);
 173                 F->read_handler = handler;
 174                 F->read_data = client_data;
 175         }
 176         if(type & COMM_SELECT_WRITE)
 177         {
 178                 kq_update_events(F, EVFILT_WRITE, handler);
 179                 F->write_handler = handler;
 180                 F->write_data = client_data;
 181         }
 182         if(timeout)
 183                 F->timeout = CurrentTime + (timeout / 1000);
 184
 185 }
 186
 187 /*
 188  * Check all connections for new connections and input data that is to be
 189  * processed. Also check for connections with data queued and whether we can
 190  * write it out.
 191  */
 192
 193 /*
 194  * comm_select
 195  *
 196  * Called to do the new-style IO, courtesy of squid (like most of this
 197  * new IO code). This routine handles the stuff we've hidden in
 198  * comm_setselect and fd_table[] and calls callbacks for IO ready
 199  * events.
 200  */
 201
 202 int
 203 comm_select(unsigned long delay)
 204 {
 205         int num, i;
 206         static struct kevent ke[KE_LENGTH];
 207         struct timespec poll_time;
 208
 209         /*
 210          * remember we are doing NANOseconds here, not micro/milli. God knows
 211          * why jlemon used a timespec, but hey, he wrote the interface, not I
 212          *   -- Adrian
 213          */
 214
 215         poll_time.tv_sec = delay / 1000;
 216
 217         poll_time.tv_nsec = (delay % 1000) * 1000000;
 218
 219         for (;;)
 220         {
 221                 num = kevent(kq, kqlst, kqoff, ke, KE_LENGTH, &poll_time);
 222                 kqoff = 0;
 223
 224                 if(num >= 0)
 225                         break;
 226
 227                 if(ignoreErrno(errno))
 228                         break;
 229
 230                 set_time();
 231
 232                 return COMM_ERROR;
 233
 234                 /* NOTREACHED */
 235         }
 236
 237         set_time();
 238
 239         if(num == 0)
 240                 return COMM_OK; /* No error.. */
 241
 242         for (i = 0; i < num; i++)
 243         {
 244                 int fd = (int) ke[i].ident;
 245                 PF *hdl = NULL;
 246                 fde_t *F = &fd_table[fd];
 247
 248                 if(ke[i].flags & EV_ERROR)
 249                 {
 250                         errno = (int) ke[i].data;
 251                         /* XXX error == bad! -- adrian */
 252                         continue;       /* XXX! */
 253                 }
 254
 255                 switch (ke[i].filter)
 256                 {
 257
 258                 case EVFILT_READ:
 259
 260                         if((hdl = F->read_handler) != NULL)
 261                         {
 262                                 F->read_handler = NULL;
 263                                 hdl(fd, F->read_data);
 264                         }
 265
 266                         break;
 267
 268                 case EVFILT_WRITE:
 269
 270                         if((hdl = F->write_handler) != NULL)
 271                         {
 272                                 F->write_handler = NULL;
 273                                 hdl(fd, F->write_data);
 274                         }
 275                         break;
 276
 277                 default:
 278                         /* Bad! -- adrian */
 279                         break;
 280                 }
 281         }
 282         return COMM_OK;
 283 }
 284