external/bsd/libevent/dist/win32select.c

   1 /*      $NetBSD: win32select.c,v 1.1.1.2 2015/01/29 06:37:53 spz Exp $  */
   2 /*
   3  * Copyright 2007-2012 Niels Provos and Nick Mathewson
   4  * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu>
   5  * Copyright 2003 Michael A. Davis <mike@datanerds.net>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The name of the author may not be used to endorse or promote products
  16  *    derived from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #include <winsock2.h>
  31 #include <windows.h>
  32 #include <sys/types.h>
  33 #include <sys/queue.h>
  34 #include <limits.h>
  35 #include <signal.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <string.h>
  39 #include <errno.h>
  40
  41 #include "event2/util.h"
  42 #include "event2/event-config.h"
  43 #include <sys/cdefs.h>
  44 __RCSID("$NetBSD: win32select.c,v 1.1.1.2 2015/01/29 06:37:53 spz Exp $");
  45 #include "util-internal.h"
  46 #include "log-internal.h"
  47 #include "event2/event.h"
  48 #include "event-internal.h"
  49 #include "evmap-internal.h"
  50 #include "event2/thread.h"
  51 #include "evthread-internal.h"
  52
  53 #define XFREE(ptr) do { if (ptr) mm_free(ptr); } while (0)
  54
  55 extern struct event_list timequeue;
  56 extern struct event_list addqueue;
  57
  58 struct win_fd_set {
  59         u_int fd_count;
  60         SOCKET fd_array[1];
  61 };
  62
  63 /* MSDN says this is required to handle SIGFPE */
  64 volatile double SIGFPE_REQ = 0.0f;
  65
  66 struct idx_info {
  67         int read_pos_plus1;
  68         int write_pos_plus1;
  69 };
  70
  71 struct win32op {
  72         unsigned num_fds_in_fd_sets;
  73         int resize_out_sets;
  74         struct win_fd_set *readset_in;
  75         struct win_fd_set *writeset_in;
  76         struct win_fd_set *readset_out;
  77         struct win_fd_set *writeset_out;
  78         struct win_fd_set *exset_out;
  79         unsigned signals_are_broken : 1;
  80 };
  81
  82 static void *win32_init(struct event_base *);
  83 static int win32_add(struct event_base *, evutil_socket_t, short old, short events, void *_idx);
  84 static int win32_del(struct event_base *, evutil_socket_t, short old, short events, void *_idx);
  85 static int win32_dispatch(struct event_base *base, struct timeval *);
  86 static void win32_dealloc(struct event_base *);
  87
  88 struct eventop win32ops = {
  89         "win32",
  90         win32_init,
  91         win32_add,
  92         win32_del,
  93         win32_dispatch,
  94         win32_dealloc,
  95         0, /* doesn't need reinit */
  96         0, /* No features supported. */
  97         sizeof(struct idx_info),
  98 };
  99
 100 #define FD_SET_ALLOC_SIZE(n) ((sizeof(struct win_fd_set) + ((n)-1)*sizeof(SOCKET)))
 101
 102 static int
 103 grow_fd_sets(struct win32op *op, unsigned new_num_fds)
 104 {
 105         size_t size;
 106
 107         EVUTIL_ASSERT(new_num_fds >= op->readset_in->fd_count &&
 108                new_num_fds >= op->writeset_in->fd_count);
 109         EVUTIL_ASSERT(new_num_fds >= 1);
 110
 111         size = FD_SET_ALLOC_SIZE(new_num_fds);
 112         if (!(op->readset_in = mm_realloc(op->readset_in, size)))
 113                 return (-1);
 114         if (!(op->writeset_in = mm_realloc(op->writeset_in, size)))
 115                 return (-1);
 116         op->resize_out_sets = 1;
 117         op->num_fds_in_fd_sets = new_num_fds;
 118         return (0);
 119 }
 120
 121 static int
 122 do_fd_set(struct win32op *op, struct idx_info *ent, evutil_socket_t s, int read)
 123 {
 124         struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
 125         if (read) {
 126                 if (ent->read_pos_plus1 > 0)
 127                         return (0);
 128         } else {
 129                 if (ent->write_pos_plus1 > 0)
 130                         return (0);
 131         }
 132         if (set->fd_count == op->num_fds_in_fd_sets) {
 133                 if (grow_fd_sets(op, op->num_fds_in_fd_sets*2))
 134                         return (-1);
 135                 /* set pointer will have changed and needs reiniting! */
 136                 set = read ? op->readset_in : op->writeset_in;
 137         }
 138         set->fd_array[set->fd_count] = s;
 139         if (read)
 140                 ent->read_pos_plus1 = set->fd_count+1;
 141         else
 142                 ent->write_pos_plus1 = set->fd_count+1;
 143         return (set->fd_count++);
 144 }
 145
 146 static int
 147 do_fd_clear(struct event_base *base,
 148                         struct win32op *op, struct idx_info *ent, int read)
 149 {
 150         int i;
 151         struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
 152         if (read) {
 153                 i = ent->read_pos_plus1 - 1;
 154                 ent->read_pos_plus1 = 0;
 155         } else {
 156                 i = ent->write_pos_plus1 - 1;
 157                 ent->write_pos_plus1 = 0;
 158         }
 159         if (i < 0)
 160                 return (0);
 161         if (--set->fd_count != (unsigned)i) {
 162                 struct idx_info *ent2;
 163                 SOCKET s2;
 164                 s2 = set->fd_array[i] = set->fd_array[set->fd_count];
 165
 166                 ent2 = evmap_io_get_fdinfo(&base->io, s2);
 167
 168                 if (!ent2) /* This indicates a bug. */
 169                         return (0);
 170                 if (read)
 171                         ent2->read_pos_plus1 = i+1;
 172                 else
 173                         ent2->write_pos_plus1 = i+1;
 174         }
 175         return (0);
 176 }
 177
 178 #define NEVENT 32
 179 void *
 180 win32_init(struct event_base *_base)
 181 {
 182         struct win32op *winop;
 183         size_t size;
 184         if (!(winop = mm_calloc(1, sizeof(struct win32op))))
 185                 return NULL;
 186         winop->num_fds_in_fd_sets = NEVENT;
 187         size = FD_SET_ALLOC_SIZE(NEVENT);
 188         if (!(winop->readset_in = mm_malloc(size)))
 189                 goto err;
 190         if (!(winop->writeset_in = mm_malloc(size)))
 191                 goto err;
 192         if (!(winop->readset_out = mm_malloc(size)))
 193                 goto err;
 194         if (!(winop->writeset_out = mm_malloc(size)))
 195                 goto err;
 196         if (!(winop->exset_out = mm_malloc(size)))
 197                 goto err;
 198         winop->readset_in->fd_count = winop->writeset_in->fd_count = 0;
 199         winop->readset_out->fd_count = winop->writeset_out->fd_count
 200                 = winop->exset_out->fd_count = 0;
 201
 202         if (evsig_init(_base) < 0)
 203                 winop->signals_are_broken = 1;
 204
 205         return (winop);
 206  err:
 207         XFREE(winop->readset_in);
 208         XFREE(winop->writeset_in);
 209         XFREE(winop->readset_out);
 210         XFREE(winop->writeset_out);
 211         XFREE(winop->exset_out);
 212         XFREE(winop);
 213         return (NULL);
 214 }
 215
 216 int
 217 win32_add(struct event_base *base, evutil_socket_t fd,
 218                          short old, short events, void *_idx)
 219 {
 220         struct win32op *win32op = base->evbase;
 221         struct idx_info *idx = _idx;
 222
 223         if ((events & EV_SIGNAL) && win32op->signals_are_broken)
 224                 return (-1);
 225
 226         if (!(events & (EV_READ|EV_WRITE)))
 227                 return (0);
 228
 229         event_debug(("%s: adding event for %d", __func__, (int)fd));
 230         if (events & EV_READ) {
 231                 if (do_fd_set(win32op, idx, fd, 1)<0)
 232                         return (-1);
 233         }
 234         if (events & EV_WRITE) {
 235                 if (do_fd_set(win32op, idx, fd, 0)<0)
 236                         return (-1);
 237         }
 238         return (0);
 239 }
 240
 241 int
 242 win32_del(struct event_base *base, evutil_socket_t fd, short old, short events,
 243                   void *_idx)
 244 {
 245         struct win32op *win32op = base->evbase;
 246         struct idx_info *idx = _idx;
 247
 248         event_debug(("%s: Removing event for "EV_SOCK_FMT,
 249                 __func__, EV_SOCK_ARG(fd)));
 250         if (events & EV_READ)
 251                 do_fd_clear(base, win32op, idx, 1);
 252         if (events & EV_WRITE)
 253                 do_fd_clear(base, win32op, idx, 0);
 254
 255         return 0;
 256 }
 257
 258 static void
 259 fd_set_copy(struct win_fd_set *out, const struct win_fd_set *in)
 260 {
 261         out->fd_count = in->fd_count;
 262         memcpy(out->fd_array, in->fd_array, in->fd_count * (sizeof(SOCKET)));
 263 }
 264
 265 /*
 266   static void dump_fd_set(struct win_fd_set *s)
 267   {
 268   unsigned int i;
 269   printf("[ ");
 270   for(i=0;i<s->fd_count;++i)
 271   printf("%d ",(int)s->fd_array[i]);
 272   printf("]\n");
 273   }
 274 */
 275
 276 int
 277 win32_dispatch(struct event_base *base, struct timeval *tv)
 278 {
 279         struct win32op *win32op = base->evbase;
 280         int res = 0;
 281         unsigned j, i;
 282         int fd_count;
 283         SOCKET s;
 284
 285         if (win32op->resize_out_sets) {
 286                 size_t size = FD_SET_ALLOC_SIZE(win32op->num_fds_in_fd_sets);
 287                 if (!(win32op->readset_out = mm_realloc(win32op->readset_out, size)))
 288                         return (-1);
 289                 if (!(win32op->exset_out = mm_realloc(win32op->exset_out, size)))
 290                         return (-1);
 291                 if (!(win32op->writeset_out = mm_realloc(win32op->writeset_out, size)))
 292                         return (-1);
 293                 win32op->resize_out_sets = 0;
 294         }
 295
 296         fd_set_copy(win32op->readset_out, win32op->readset_in);
 297         fd_set_copy(win32op->exset_out, win32op->writeset_in);
 298         fd_set_copy(win32op->writeset_out, win32op->writeset_in);
 299
 300         fd_count =
 301             (win32op->readset_out->fd_count > win32op->writeset_out->fd_count) ?
 302             win32op->readset_out->fd_count : win32op->writeset_out->fd_count;
 303
 304         if (!fd_count) {
 305                 long msec = tv ? evutil_tv_to_msec(tv) : LONG_MAX;
 306                 /* Sleep's DWORD argument is unsigned long */
 307                 if (msec < 0)
 308                         msec = LONG_MAX;
 309                 /* Windows doesn't like you to call select() with no sockets */
 310                 Sleep(msec);
 311                 return (0);
 312         }
 313
 314         EVBASE_RELEASE_LOCK(base, th_base_lock);
 315
 316         res = select(fd_count,
 317                      (struct fd_set*)win32op->readset_out,
 318                      (struct fd_set*)win32op->writeset_out,
 319                      (struct fd_set*)win32op->exset_out, tv);
 320
 321         EVBASE_ACQUIRE_LOCK(base, th_base_lock);
 322
 323         event_debug(("%s: select returned %d", __func__, res));
 324
 325         if (res <= 0) {
 326                 return res;
 327         }
 328
 329         if (win32op->readset_out->fd_count) {
 330                 i = rand() % win32op->readset_out->fd_count;
 331                 for (j=0; j<win32op->readset_out->fd_count; ++j) {
 332                         if (++i >= win32op->readset_out->fd_count)
 333                                 i = 0;
 334                         s = win32op->readset_out->fd_array[i];
 335                         evmap_io_active(base, s, EV_READ);
 336                 }
 337         }
 338         if (win32op->exset_out->fd_count) {
 339                 i = rand() % win32op->exset_out->fd_count;
 340                 for (j=0; j<win32op->exset_out->fd_count; ++j) {
 341                         if (++i >= win32op->exset_out->fd_count)
 342                                 i = 0;
 343                         s = win32op->exset_out->fd_array[i];
 344                         evmap_io_active(base, s, EV_WRITE);
 345                 }
 346         }
 347         if (win32op->writeset_out->fd_count) {
 348                 SOCKET s;
 349                 i = rand() % win32op->writeset_out->fd_count;
 350                 for (j=0; j<win32op->writeset_out->fd_count; ++j) {
 351                         if (++i >= win32op->writeset_out->fd_count)
 352                                 i = 0;
 353                         s = win32op->writeset_out->fd_array[i];
 354                         evmap_io_active(base, s, EV_WRITE);
 355                 }
 356         }
 357         return (0);
 358 }
 359
 360 void
 361 win32_dealloc(struct event_base *_base)
 362 {
 363         struct win32op *win32op = _base->evbase;
 364
 365         evsig_dealloc(_base);
 366         if (win32op->readset_in)
 367                 mm_free(win32op->readset_in);
 368         if (win32op->writeset_in)
 369                 mm_free(win32op->writeset_in);
 370         if (win32op->readset_out)
 371                 mm_free(win32op->readset_out);
 372         if (win32op->writeset_out)
 373                 mm_free(win32op->writeset_out);
 374         if (win32op->exset_out)
 375                 mm_free(win32op->exset_out);
 376         /* XXXXX free the tree. */
 377
 378         memset(win32op, 0, sizeof(*win32op));
 379         mm_free(win32op);
 380 }