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Comparing libev/ev_select.c (file contents):
Revision 1.24 by root, Sun Dec 9 02:12:44 2007 UTC vs.
Revision 1.48 by root, Fri Oct 15 22:44:42 2010 UTC

1/* 1/*
2 * libev select fd activity backend 2 * libev select fd activity backend
3 * 3 *
4 * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de> 4 * Copyright (c) 2007,2008,2009 Marc Alexander Lehmann <libev@schmorp.de>
5 * All rights reserved. 5 * All rights reserved.
6 * 6 *
7 * Redistribution and use in source and binary forms, with or without 7 * Redistribution and use in source and binary forms, with or without modifica-
8 * modification, are permitted provided that the following conditions are 8 * tion, are permitted provided that the following conditions are met:
9 * met: 9 *
10 * 1. Redistributions of source code must retain the above copyright notice,
11 * this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE.
10 * 27 *
11 * * Redistributions of source code must retain the above copyright 28 * Alternatively, the contents of this file may be used under the terms of
12 * notice, this list of conditions and the following disclaimer. 29 * the GNU General Public License ("GPL") version 2 or any later version,
13 * 30 * in which case the provisions of the GPL are applicable instead of
14 * * Redistributions in binary form must reproduce the above 31 * the above. If you wish to allow the use of your version of this file
15 * copyright notice, this list of conditions and the following 32 * only under the terms of the GPL and not to allow others to use your
16 * disclaimer in the documentation and/or other materials provided 33 * version of this file under the BSD license, indicate your decision
17 * with the distribution. 34 * by deleting the provisions above and replace them with the notice
18 * 35 * and other provisions required by the GPL. If you do not delete the
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 36 * provisions above, a recipient may use your version of this file under
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 37 * either the BSD or the GPL.
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */ 38 */
31 39
32#ifndef _WIN32 40#ifndef _WIN32
33/* for unix systems */ 41/* for unix systems */
34# include <sys/select.h> 42# include <sys/select.h>
44#endif 52#endif
45 53
46#if EV_SELECT_IS_WINSOCKET 54#if EV_SELECT_IS_WINSOCKET
47# undef EV_SELECT_USE_FD_SET 55# undef EV_SELECT_USE_FD_SET
48# define EV_SELECT_USE_FD_SET 1 56# define EV_SELECT_USE_FD_SET 1
49# undef EINTR 57# undef NFDBITS
50# define EINTR WSAEINTR 58# define NFDBITS 0
51# undef EBADF
52# define EBADF WSAENOTSOCK
53# undef ENOMEM
54# define ENOMEM (errno + 1)
55#endif 59#endif
56 60
57#if !EV_SELECT_USE_FD_SET 61#if !EV_SELECT_USE_FD_SET
58# define NFDBYTES (NFDBITS / 8) 62# define NFDBYTES (NFDBITS / 8)
59#endif 63#endif
73 SOCKET handle = anfds [fd].handle; 77 SOCKET handle = anfds [fd].handle;
74 #else 78 #else
75 int handle = fd; 79 int handle = fd;
76 #endif 80 #endif
77 81
82 assert (("libev: fd >= FD_SETSIZE passed to fd_set-based select backend", fd < FD_SETSIZE));
83
84 /* FD_SET is broken on windows (it adds the fd to a set twice or more,
85 * which eventually leads to overflows). Need to call it only on changes.
86 */
87 #if EV_SELECT_IS_WINSOCKET
88 if ((oev ^ nev) & EV_READ)
89 #endif
78 if (nev & EV_READ) 90 if (nev & EV_READ)
79 FD_SET (handle, (fd_set *)vec_ri); 91 FD_SET (handle, (fd_set *)vec_ri);
80 else 92 else
81 FD_CLR (handle, (fd_set *)vec_ri); 93 FD_CLR (handle, (fd_set *)vec_ri);
82 94
95 #if EV_SELECT_IS_WINSOCKET
96 if ((oev ^ nev) & EV_WRITE)
97 #endif
83 if (nev & EV_WRITE) 98 if (nev & EV_WRITE)
84 FD_SET (handle, (fd_set *)vec_wi); 99 FD_SET (handle, (fd_set *)vec_wi);
85 else 100 else
86 FD_CLR (handle, (fd_set *)vec_wi); 101 FD_CLR (handle, (fd_set *)vec_wi);
87 102
88#else 103#else
89 104
90 int word = fd / NFDBITS; 105 int word = fd / NFDBITS;
91 int mask = 1UL << (fd % NFDBITS); 106 fd_mask mask = 1UL << (fd % NFDBITS);
92 107
93 if (expect_false (vec_max < word + 1)) 108 if (expect_false (vec_max <= word))
94 { 109 {
95 int new_max = word + 1; 110 int new_max = word + 1;
96 111
97 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES); 112 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
98 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */ 113 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
99 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES); 114 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
100 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */ 115 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
116 #ifdef _WIN32
117 vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
118 #endif
101 119
102 for (; vec_max < new_max; ++vec_max) 120 for (; vec_max < new_max; ++vec_max)
103 ((fd_mask *)vec_ri)[vec_max] = 121 ((fd_mask *)vec_ri) [vec_max] =
104 ((fd_mask *)vec_wi)[vec_max] = 0; 122 ((fd_mask *)vec_wi) [vec_max] = 0;
105 } 123 }
106 124
107 ((fd_mask *)vec_ri) [word] |= mask; 125 ((fd_mask *)vec_ri) [word] |= mask;
108 if (!(nev & EV_READ)) 126 if (!(nev & EV_READ))
109 ((fd_mask *)vec_ri) [word] &= ~mask; 127 ((fd_mask *)vec_ri) [word] &= ~mask;
118static void 136static void
119select_poll (EV_P_ ev_tstamp timeout) 137select_poll (EV_P_ ev_tstamp timeout)
120{ 138{
121 struct timeval tv; 139 struct timeval tv;
122 int res; 140 int res;
141 int fd_setsize;
142
143 EV_RELEASE_CB;
144 EV_TV_SET (tv, timeout);
123 145
124#if EV_SELECT_USE_FD_SET 146#if EV_SELECT_USE_FD_SET
147 fd_setsize = sizeof (fd_set);
148#else
149 fd_setsize = vec_max * NFDBYTES;
150#endif
151
125 memcpy (vec_ro, vec_ri, sizeof (fd_set)); 152 memcpy (vec_ro, vec_ri, fd_setsize);
126 memcpy (vec_wo, vec_wi, sizeof (fd_set)); 153 memcpy (vec_wo, vec_wi, fd_setsize);
127#else
128 memcpy (vec_ro, vec_ri, vec_max * NFDBYTES);
129 memcpy (vec_wo, vec_wi, vec_max * NFDBYTES);
130#endif
131 154
132 tv.tv_sec = (long)timeout; 155#ifdef _WIN32
133 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 156 /* pass in the write set as except set.
134 157 * the idea behind this is to work around a windows bug that causes
158 * errors to be reported as an exception and not by setting
159 * the writable bit. this is so uncontrollably lame.
160 */
161 memcpy (vec_eo, vec_wi, fd_setsize);
162 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
163#elif EV_SELECT_USE_FD_SET
164 fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
165 res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
166#else
135 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 167 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
168#endif
169 EV_ACQUIRE_CB;
136 170
137 if (expect_false (res < 0)) 171 if (expect_false (res < 0))
138 { 172 {
139 #if EV_SELECT_IS_WINSOCKET 173 #if EV_SELECT_IS_WINSOCKET
140 errno = WSAGetLastError (); 174 errno = WSAGetLastError ();
141 #endif 175 #endif
176 #ifdef WSABASEERR
177 /* on windows, select returns incompatible error codes, fix this */
178 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
179 if (errno == WSAENOTSOCK)
180 errno = EBADF;
181 else
182 errno -= WSABASEERR;
183 #endif
184
185 #ifdef _WIN32
186 /* select on windows erroneously returns EINVAL when no fd sets have been
187 * provided (this is documented). what microsoft doesn't tell you that this bug
188 * exists even when the fd sets _are_ provided, so we have to check for this bug
189 * here and emulate by sleeping manually.
190 * we also get EINVAL when the timeout is invalid, but we ignore this case here
191 * and assume that EINVAL always means: you have to wait manually.
192 */
193 if (errno == EINVAL)
194 {
195 ev_sleep (timeout);
196 return;
197 }
198 #endif
142 199
143 if (errno == EBADF) 200 if (errno == EBADF)
144 fd_ebadf (EV_A); 201 fd_ebadf (EV_A);
145 else if (errno == ENOMEM && !syserr_cb) 202 else if (errno == ENOMEM && !syserr_cb)
146 fd_enomem (EV_A); 203 fd_enomem (EV_A);
147 else if (errno != EINTR) 204 else if (errno != EINTR)
148 syserr ("(libev) select"); 205 ev_syserr ("(libev) select");
149 206
150 return; 207 return;
151 } 208 }
152 209
153#if EV_SELECT_USE_FD_SET 210#if EV_SELECT_USE_FD_SET
165 int handle = fd; 222 int handle = fd;
166 #endif 223 #endif
167 224
168 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ; 225 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
169 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE; 226 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
227 #ifdef _WIN32
228 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
229 #endif
170 230
171 if (expect_true (events)) 231 if (expect_true (events))
172 fd_event (EV_A_ fd, events); 232 fd_event (EV_A_ fd, events);
173 } 233 }
174 } 234 }
179 int word, bit; 239 int word, bit;
180 for (word = vec_max; word--; ) 240 for (word = vec_max; word--; )
181 { 241 {
182 fd_mask word_r = ((fd_mask *)vec_ro) [word]; 242 fd_mask word_r = ((fd_mask *)vec_ro) [word];
183 fd_mask word_w = ((fd_mask *)vec_wo) [word]; 243 fd_mask word_w = ((fd_mask *)vec_wo) [word];
244 #ifdef _WIN32
245 word_w |= ((fd_mask *)vec_eo) [word];
246 #endif
184 247
185 if (word_r || word_w) 248 if (word_r || word_w)
186 for (bit = NFDBITS; bit--; ) 249 for (bit = NFDBITS; bit--; )
187 { 250 {
188 fd_mask mask = 1UL << bit; 251 fd_mask mask = 1UL << bit;
201} 264}
202 265
203int inline_size 266int inline_size
204select_init (EV_P_ int flags) 267select_init (EV_P_ int flags)
205{ 268{
206 backend_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 269 backend_fudge = 0.; /* posix says this is zero */
207 backend_modify = select_modify; 270 backend_modify = select_modify;
208 backend_poll = select_poll; 271 backend_poll = select_poll;
209 272
210#if EV_SELECT_USE_FD_SET 273#if EV_SELECT_USE_FD_SET
211 vec_max = FD_SETSIZE / 32;
212 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri); 274 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
213 vec_ro = ev_malloc (sizeof (fd_set)); 275 vec_ro = ev_malloc (sizeof (fd_set));
214 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi); 276 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
215 vec_wo = ev_malloc (sizeof (fd_set)); 277 vec_wo = ev_malloc (sizeof (fd_set));
278 #ifdef _WIN32
279 vec_eo = ev_malloc (sizeof (fd_set));
280 #endif
216#else 281#else
217 vec_max = 0; 282 vec_max = 0;
218 vec_ri = 0; 283 vec_ri = 0;
219 vec_ri = 0; 284 vec_ro = 0;
285 vec_wi = 0;
220 vec_wo = 0; 286 vec_wo = 0;
287 #ifdef _WIN32
221 vec_wo = 0; 288 vec_eo = 0;
289 #endif
222#endif 290#endif
223 291
224 return EVBACKEND_SELECT; 292 return EVBACKEND_SELECT;
225} 293}
226 294
229{ 297{
230 ev_free (vec_ri); 298 ev_free (vec_ri);
231 ev_free (vec_ro); 299 ev_free (vec_ro);
232 ev_free (vec_wi); 300 ev_free (vec_wi);
233 ev_free (vec_wo); 301 ev_free (vec_wo);
302 #ifdef _WIN32
303 ev_free (vec_eo);
304 #endif
234} 305}
235 306
236 307

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