1 /* $NetBSD: win32select.c,v 1.1.1.4 2021/04/07 02:43:14 christos 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 #include "event2/event-config.h" 30 #include <sys/cdefs.h> 31 __RCSID("$NetBSD: win32select.c,v 1.1.1.4 2021/04/07 02:43:14 christos Exp $"); 32 #include "evconfig-private.h" 33 34 #ifdef _WIN32 35 36 #include <winsock2.h> 37 #include <windows.h> 38 #include <sys/types.h> 39 #include <sys/queue.h> 40 #include <limits.h> 41 #include <signal.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <errno.h> 46 47 #include "event2/util.h" 48 #include "util-internal.h" 49 #include "log-internal.h" 50 #include "event2/event.h" 51 #include "event-internal.h" 52 #include "evmap-internal.h" 53 #include "event2/thread.h" 54 #include "evthread-internal.h" 55 #include "time-internal.h" 56 57 #define XFREE(ptr) do { if (ptr) mm_free(ptr); } while (0) 58 59 extern struct event_list timequeue; 60 extern struct event_list addqueue; 61 62 struct win_fd_set { 63 unsigned int fd_count; 64 SOCKET fd_array[1]; 65 }; 66 67 /* MSDN says this is required to handle SIGFPE */ 68 volatile double SIGFPE_REQ = 0.0f; 69 70 struct idx_info { 71 int read_pos_plus1; 72 int write_pos_plus1; 73 }; 74 75 struct win32op { 76 unsigned num_fds_in_fd_sets; 77 int resize_out_sets; 78 struct win_fd_set *readset_in; 79 struct win_fd_set *writeset_in; 80 struct win_fd_set *readset_out; 81 struct win_fd_set *writeset_out; 82 struct win_fd_set *exset_out; 83 unsigned signals_are_broken : 1; 84 }; 85 86 static void *win32_init(struct event_base *); 87 static int win32_add(struct event_base *, evutil_socket_t, short old, short events, void *idx_); 88 static int win32_del(struct event_base *, evutil_socket_t, short old, short events, void *idx_); 89 static int win32_dispatch(struct event_base *base, struct timeval *); 90 static void win32_dealloc(struct event_base *); 91 92 struct eventop win32ops = { 93 "win32", 94 win32_init, 95 win32_add, 96 win32_del, 97 win32_dispatch, 98 win32_dealloc, 99 0, /* doesn't need reinit */ 100 0, /* No features supported. */ 101 sizeof(struct idx_info), 102 }; 103 104 #define FD_SET_ALLOC_SIZE(n) ((sizeof(struct win_fd_set) + ((n)-1)*sizeof(SOCKET))) 105 106 static int 107 grow_fd_sets(struct win32op *op, unsigned new_num_fds) 108 { 109 size_t size; 110 111 EVUTIL_ASSERT(new_num_fds >= op->readset_in->fd_count && 112 new_num_fds >= op->writeset_in->fd_count); 113 EVUTIL_ASSERT(new_num_fds >= 1); 114 115 size = FD_SET_ALLOC_SIZE(new_num_fds); 116 if (!(op->readset_in = mm_realloc(op->readset_in, size))) 117 return (-1); 118 if (!(op->writeset_in = mm_realloc(op->writeset_in, size))) 119 return (-1); 120 op->resize_out_sets = 1; 121 op->num_fds_in_fd_sets = new_num_fds; 122 return (0); 123 } 124 125 static int 126 do_fd_set(struct win32op *op, struct idx_info *ent, evutil_socket_t s, int read) 127 { 128 struct win_fd_set *set = read ? op->readset_in : op->writeset_in; 129 if (read) { 130 if (ent->read_pos_plus1 > 0) 131 return (0); 132 } else { 133 if (ent->write_pos_plus1 > 0) 134 return (0); 135 } 136 if (set->fd_count == op->num_fds_in_fd_sets) { 137 if (grow_fd_sets(op, op->num_fds_in_fd_sets*2)) 138 return (-1); 139 /* set pointer will have changed and needs reiniting! */ 140 set = read ? op->readset_in : op->writeset_in; 141 } 142 set->fd_array[set->fd_count] = s; 143 if (read) 144 ent->read_pos_plus1 = set->fd_count+1; 145 else 146 ent->write_pos_plus1 = set->fd_count+1; 147 return (set->fd_count++); 148 } 149 150 static int 151 do_fd_clear(struct event_base *base, 152 struct win32op *op, struct idx_info *ent, int read) 153 { 154 int i; 155 struct win_fd_set *set = read ? op->readset_in : op->writeset_in; 156 if (read) { 157 i = ent->read_pos_plus1 - 1; 158 ent->read_pos_plus1 = 0; 159 } else { 160 i = ent->write_pos_plus1 - 1; 161 ent->write_pos_plus1 = 0; 162 } 163 if (i < 0) 164 return (0); 165 if (--set->fd_count != (unsigned)i) { 166 struct idx_info *ent2; 167 SOCKET s2; 168 s2 = set->fd_array[i] = set->fd_array[set->fd_count]; 169 170 ent2 = evmap_io_get_fdinfo_(&base->io, s2); 171 172 if (!ent2) /* This indicates a bug. */ 173 return (0); 174 if (read) 175 ent2->read_pos_plus1 = i+1; 176 else 177 ent2->write_pos_plus1 = i+1; 178 } 179 return (0); 180 } 181 182 #define NEVENT 32 183 void * 184 win32_init(struct event_base *base) 185 { 186 struct win32op *winop; 187 size_t size; 188 if (!(winop = mm_calloc(1, sizeof(struct win32op)))) 189 return NULL; 190 winop->num_fds_in_fd_sets = NEVENT; 191 size = FD_SET_ALLOC_SIZE(NEVENT); 192 if (!(winop->readset_in = mm_malloc(size))) 193 goto err; 194 if (!(winop->writeset_in = mm_malloc(size))) 195 goto err; 196 if (!(winop->readset_out = mm_malloc(size))) 197 goto err; 198 if (!(winop->writeset_out = mm_malloc(size))) 199 goto err; 200 if (!(winop->exset_out = mm_malloc(size))) 201 goto err; 202 winop->readset_in->fd_count = winop->writeset_in->fd_count = 0; 203 winop->readset_out->fd_count = winop->writeset_out->fd_count 204 = winop->exset_out->fd_count = 0; 205 206 if (evsig_init_(base) < 0) 207 winop->signals_are_broken = 1; 208 209 evutil_weakrand_seed_(&base->weakrand_seed, 0); 210 211 return (winop); 212 err: 213 XFREE(winop->readset_in); 214 XFREE(winop->writeset_in); 215 XFREE(winop->readset_out); 216 XFREE(winop->writeset_out); 217 XFREE(winop->exset_out); 218 XFREE(winop); 219 return (NULL); 220 } 221 222 int 223 win32_add(struct event_base *base, evutil_socket_t fd, 224 short old, short events, void *idx_) 225 { 226 struct win32op *win32op = base->evbase; 227 struct idx_info *idx = idx_; 228 229 if ((events & EV_SIGNAL) && win32op->signals_are_broken) 230 return (-1); 231 232 if (!(events & (EV_READ|EV_WRITE))) 233 return (0); 234 235 event_debug(("%s: adding event for %d", __func__, (int)fd)); 236 if (events & EV_READ) { 237 if (do_fd_set(win32op, idx, fd, 1)<0) 238 return (-1); 239 } 240 if (events & EV_WRITE) { 241 if (do_fd_set(win32op, idx, fd, 0)<0) 242 return (-1); 243 } 244 return (0); 245 } 246 247 int 248 win32_del(struct event_base *base, evutil_socket_t fd, short old, short events, 249 void *idx_) 250 { 251 struct win32op *win32op = base->evbase; 252 struct idx_info *idx = idx_; 253 254 event_debug(("%s: Removing event for "EV_SOCK_FMT, 255 __func__, EV_SOCK_ARG(fd))); 256 if (events & EV_READ) 257 do_fd_clear(base, win32op, idx, 1); 258 if (events & EV_WRITE) 259 do_fd_clear(base, win32op, idx, 0); 260 261 return 0; 262 } 263 264 static void 265 fd_set_copy(struct win_fd_set *out, const struct win_fd_set *in) 266 { 267 out->fd_count = in->fd_count; 268 memcpy(out->fd_array, in->fd_array, in->fd_count * (sizeof(SOCKET))); 269 } 270 271 /* 272 static void dump_fd_set(struct win_fd_set *s) 273 { 274 unsigned int i; 275 printf("[ "); 276 for(i=0;i<s->fd_count;++i) 277 printf("%d ",(int)s->fd_array[i]); 278 printf("]\n"); 279 } 280 */ 281 282 int 283 win32_dispatch(struct event_base *base, struct timeval *tv) 284 { 285 struct win32op *win32op = base->evbase; 286 int res = 0; 287 unsigned j, i; 288 int fd_count; 289 SOCKET s; 290 291 if (win32op->resize_out_sets) { 292 size_t size = FD_SET_ALLOC_SIZE(win32op->num_fds_in_fd_sets); 293 if (!(win32op->readset_out = mm_realloc(win32op->readset_out, size))) 294 return (-1); 295 if (!(win32op->exset_out = mm_realloc(win32op->exset_out, size))) 296 return (-1); 297 if (!(win32op->writeset_out = mm_realloc(win32op->writeset_out, size))) 298 return (-1); 299 win32op->resize_out_sets = 0; 300 } 301 302 fd_set_copy(win32op->readset_out, win32op->readset_in); 303 fd_set_copy(win32op->exset_out, win32op->writeset_in); 304 fd_set_copy(win32op->writeset_out, win32op->writeset_in); 305 306 fd_count = 307 (win32op->readset_out->fd_count > win32op->writeset_out->fd_count) ? 308 win32op->readset_out->fd_count : win32op->writeset_out->fd_count; 309 310 if (!fd_count) { 311 long msec = tv ? evutil_tv_to_msec_(tv) : LONG_MAX; 312 /* Sleep's DWORD argument is unsigned long */ 313 if (msec < 0) 314 msec = LONG_MAX; 315 /* Windows doesn't like you to call select() with no sockets */ 316 Sleep(msec); 317 return (0); 318 } 319 320 EVBASE_RELEASE_LOCK(base, th_base_lock); 321 322 res = select(fd_count, 323 (struct fd_set*)win32op->readset_out, 324 (struct fd_set*)win32op->writeset_out, 325 (struct fd_set*)win32op->exset_out, tv); 326 327 EVBASE_ACQUIRE_LOCK(base, th_base_lock); 328 329 event_debug(("%s: select returned %d", __func__, res)); 330 331 if (res <= 0) { 332 event_debug(("%s: %s", __func__, 333 evutil_socket_error_to_string(EVUTIL_SOCKET_ERROR()))); 334 return res; 335 } 336 337 if (win32op->readset_out->fd_count) { 338 i = evutil_weakrand_range_(&base->weakrand_seed, 339 win32op->readset_out->fd_count); 340 for (j=0; j<win32op->readset_out->fd_count; ++j) { 341 if (++i >= win32op->readset_out->fd_count) 342 i = 0; 343 s = win32op->readset_out->fd_array[i]; 344 evmap_io_active_(base, s, EV_READ); 345 } 346 } 347 if (win32op->exset_out->fd_count) { 348 i = evutil_weakrand_range_(&base->weakrand_seed, 349 win32op->exset_out->fd_count); 350 for (j=0; j<win32op->exset_out->fd_count; ++j) { 351 if (++i >= win32op->exset_out->fd_count) 352 i = 0; 353 s = win32op->exset_out->fd_array[i]; 354 evmap_io_active_(base, s, EV_WRITE); 355 } 356 } 357 if (win32op->writeset_out->fd_count) { 358 i = evutil_weakrand_range_(&base->weakrand_seed, 359 win32op->writeset_out->fd_count); 360 for (j=0; j<win32op->writeset_out->fd_count; ++j) { 361 if (++i >= win32op->writeset_out->fd_count) 362 i = 0; 363 s = win32op->writeset_out->fd_array[i]; 364 evmap_io_active_(base, s, EV_WRITE); 365 } 366 } 367 return (0); 368 } 369 370 void 371 win32_dealloc(struct event_base *base) 372 { 373 struct win32op *win32op = base->evbase; 374 375 evsig_dealloc_(base); 376 if (win32op->readset_in) 377 mm_free(win32op->readset_in); 378 if (win32op->writeset_in) 379 mm_free(win32op->writeset_in); 380 if (win32op->readset_out) 381 mm_free(win32op->readset_out); 382 if (win32op->writeset_out) 383 mm_free(win32op->writeset_out); 384 if (win32op->exset_out) 385 mm_free(win32op->exset_out); 386 /* XXXXX free the tree. */ 387 388 memset(win32op, 0, sizeof(*win32op)); 389 mm_free(win32op); 390 } 391 392 #endif 393