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Comparing libev/ev_select.c (file contents):
Revision 1.11 by root, Sun Nov 4 00:24:17 2007 UTC vs.
Revision 1.46 by root, Sun Jul 19 04:06:13 2009 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/* for broken bsd's */ 40#ifndef _WIN32
33#include <sys/time.h>
34#include <sys/types.h>
35#include <unistd.h>
36
37/* for unix systems */ 41/* for unix systems */
38#ifndef WIN32
39# include <sys/select.h> 42# include <sys/select.h>
43# include <inttypes.h>
44#endif
45
46#ifndef EV_SELECT_USE_FD_SET
47# ifdef NFDBITS
48# define EV_SELECT_USE_FD_SET 0
49# else
50# define EV_SELECT_USE_FD_SET 1
51# endif
52#endif
53
54#if EV_SELECT_IS_WINSOCKET
55# undef EV_SELECT_USE_FD_SET
56# define EV_SELECT_USE_FD_SET 1
57# undef NFDBITS
58# define NFDBITS 0
59#endif
60
61#if !EV_SELECT_USE_FD_SET
62# define NFDBYTES (NFDBITS / 8)
40#endif 63#endif
41 64
42#include <string.h> 65#include <string.h>
43#include <inttypes.h>
44 66
45static void 67static void
46select_modify (EV_P_ int fd, int oev, int nev) 68select_modify (EV_P_ int fd, int oev, int nev)
47{ 69{
48 int offs = fd >> 3; 70 if (oev == nev)
49 int mask = 1 << (fd & 7); 71 return;
50 72
51 if (vec_max < (fd >> 5) + 1) 73 {
74#if EV_SELECT_USE_FD_SET
75
76 #if EV_SELECT_IS_WINSOCKET
77 SOCKET handle = anfds [fd].handle;
78 #else
79 int handle = fd;
80 #endif
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
90 if (nev & EV_READ)
91 FD_SET (handle, (fd_set *)vec_ri);
92 else
93 FD_CLR (handle, (fd_set *)vec_ri);
94
95 #if EV_SELECT_IS_WINSOCKET
96 if ((oev ^ nev) & EV_WRITE)
97 #endif
98 if (nev & EV_WRITE)
99 FD_SET (handle, (fd_set *)vec_wi);
100 else
101 FD_CLR (handle, (fd_set *)vec_wi);
102
103#else
104
105 int word = fd / NFDBITS;
106 fd_mask mask = 1UL << (fd % NFDBITS);
107
108 if (expect_false (vec_max <= word))
52 { 109 {
53 int new_max = (fd >> 5) + 1; 110 int new_max = word + 1;
54 111
55 vec_ri = (unsigned char *)realloc (vec_ri, new_max * 4); 112 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
56 vec_ro = (unsigned char *)realloc (vec_ro, new_max * 4); /* could free/malloc */ 113 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
57 vec_wi = (unsigned char *)realloc (vec_wi, new_max * 4); 114 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
58 vec_wo = (unsigned char *)realloc (vec_wo, new_max * 4); /* 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
59 119
60 for (; vec_max < new_max; ++vec_max) 120 for (; vec_max < new_max; ++vec_max)
61 ((uint32_t *)vec_ri)[vec_max] = 121 ((fd_mask *)vec_ri) [vec_max] =
62 ((uint32_t *)vec_wi)[vec_max] = 0; 122 ((fd_mask *)vec_wi) [vec_max] = 0;
63 } 123 }
64 124
65 vec_ri [offs] |= mask; 125 ((fd_mask *)vec_ri) [word] |= mask;
66 if (!(nev & EV_READ)) 126 if (!(nev & EV_READ))
67 vec_ri [offs] &= ~mask; 127 ((fd_mask *)vec_ri) [word] &= ~mask;
68 128
69 vec_wi [offs] |= mask; 129 ((fd_mask *)vec_wi) [word] |= mask;
70 if (!(nev & EV_WRITE)) 130 if (!(nev & EV_WRITE))
71 vec_wi [offs] &= ~mask; 131 ((fd_mask *)vec_wi) [word] &= ~mask;
132#endif
133 }
72} 134}
73 135
74static void 136static void
75select_poll (EV_P_ ev_tstamp timeout) 137select_poll (EV_P_ ev_tstamp timeout)
76{ 138{
77 struct timeval tv; 139 struct timeval tv;
78 int res; 140 int res;
141 int fd_setsize;
79 142
80 memcpy (vec_ro, vec_ri, vec_max * 4); 143 EV_RELEASE_CB;
81 memcpy (vec_wo, vec_wi, vec_max * 4);
82
83 tv.tv_sec = (long)timeout; 144 tv.tv_sec = (long)timeout;
84 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 145 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
85 146
147#if EV_SELECT_USE_FD_SET
148 fd_setsize = sizeof (fd_set);
149#else
150 fd_setsize = vec_max * NFDBYTES;
151#endif
152
153 memcpy (vec_ro, vec_ri, fd_setsize);
154 memcpy (vec_wo, vec_wi, fd_setsize);
155
156#ifdef _WIN32
157 /* pass in the write set as except set.
158 * the idea behind this is to work around a windows bug that causes
159 * errors to be reported as an exception and not by setting
160 * the writable bit. this is so uncontrollably lame.
161 */
162 memcpy (vec_eo, vec_wi, fd_setsize);
163 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
164#elif EV_SELECT_USE_FD_SET
165 fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
166 res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
167#else
86 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 168 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
169#endif
170 EV_ACQUIRE_CB;
87 171
88 if (res > 0) 172 if (expect_false (res < 0))
89 { 173 {
90 int word, offs; 174 #if EV_SELECT_IS_WINSOCKET
175 errno = WSAGetLastError ();
176 #endif
177 #ifdef WSABASEERR
178 /* on windows, select returns incompatible error codes, fix this */
179 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
180 if (errno == WSAENOTSOCK)
181 errno = EBADF;
182 else
183 errno -= WSABASEERR;
184 #endif
91 185
92 for (word = vec_max; word--; ) 186 #ifdef _WIN32
187 /* select on windows errornously returns EINVAL when no fd sets have been
188 * provided (this is documented). what microsoft doesn't tell you that this bug
189 * exists even when the fd sets _are_ provided, so we have to check for this bug
190 * here and emulate by sleeping manually.
191 * we also get EINVAL when the timeout is invalid, but we ignore this case here
192 * and assume that EINVAL always means: you have to wait manually.
193 */
194 if (errno == EINVAL)
93 { 195 {
94 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 196 ev_sleep (timeout);
95 for (offs = 4; offs--; ) 197 return;
96 {
97 int idx = word * 4 + offs;
98 unsigned char byte_r = vec_ro [idx];
99 unsigned char byte_w = vec_wo [idx];
100 int bit;
101
102 if (byte_r | byte_w)
103 for (bit = 8; bit--; )
104 {
105 int events = 0;
106 events |= byte_r & (1 << bit) ? EV_READ : 0;
107 events |= byte_w & (1 << bit) ? EV_WRITE : 0;
108
109 if (events)
110 fd_event (EV_A_ idx * 8 + bit, events);
111 }
112 }
113 } 198 }
114 } 199 #endif
115 else if (res < 0) 200
116 {
117 if (errno == EBADF) 201 if (errno == EBADF)
118 fd_ebadf (EV_A); 202 fd_ebadf (EV_A);
119 else if (errno == ENOMEM) 203 else if (errno == ENOMEM && !syserr_cb)
120 fd_enomem (EV_A); 204 fd_enomem (EV_A);
205 else if (errno != EINTR)
206 ev_syserr ("(libev) select");
207
208 return;
121 } 209 }
210
211#if EV_SELECT_USE_FD_SET
212
213 {
214 int fd;
215
216 for (fd = 0; fd < anfdmax; ++fd)
217 if (anfds [fd].events)
218 {
219 int events = 0;
220 #if EV_SELECT_IS_WINSOCKET
221 SOCKET handle = anfds [fd].handle;
222 #else
223 int handle = fd;
224 #endif
225
226 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
227 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
228 #ifdef _WIN32
229 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
230 #endif
231
232 if (expect_true (events))
233 fd_event (EV_A_ fd, events);
234 }
235 }
236
237#else
238
239 {
240 int word, bit;
241 for (word = vec_max; word--; )
242 {
243 fd_mask word_r = ((fd_mask *)vec_ro) [word];
244 fd_mask word_w = ((fd_mask *)vec_wo) [word];
245 #ifdef _WIN32
246 word_w |= ((fd_mask *)vec_eo) [word];
247 #endif
248
249 if (word_r || word_w)
250 for (bit = NFDBITS; bit--; )
251 {
252 fd_mask mask = 1UL << bit;
253 int events = 0;
254
255 events |= word_r & mask ? EV_READ : 0;
256 events |= word_w & mask ? EV_WRITE : 0;
257
258 if (expect_true (events))
259 fd_event (EV_A_ word * NFDBITS + bit, events);
260 }
261 }
262 }
263
264#endif
122} 265}
123 266
124static int 267int inline_size
125select_init (EV_P_ int flags) 268select_init (EV_P_ int flags)
126{ 269{
127 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 270 backend_fudge = 0.; /* posix says this is zero */
128 method_modify = select_modify; 271 backend_modify = select_modify;
129 method_poll = select_poll; 272 backend_poll = select_poll;
130 273
274#if EV_SELECT_USE_FD_SET
275 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
276 vec_ro = ev_malloc (sizeof (fd_set));
277 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
278 vec_wo = ev_malloc (sizeof (fd_set));
279 #ifdef _WIN32
280 vec_eo = ev_malloc (sizeof (fd_set));
281 #endif
282#else
283 vec_max = 0;
284 vec_ri = 0;
285 vec_ro = 0;
286 vec_wi = 0;
287 vec_wo = 0;
288 #ifdef _WIN32
289 vec_eo = 0;
290 #endif
291#endif
292
131 return EVMETHOD_SELECT; 293 return EVBACKEND_SELECT;
132} 294}
133 295
296void inline_size
297select_destroy (EV_P)
298{
299 ev_free (vec_ri);
300 ev_free (vec_ro);
301 ev_free (vec_wi);
302 ev_free (vec_wo);
303 #ifdef _WIN32
304 ev_free (vec_eo);
305 #endif
306}
307
308

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