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Comparing libev/ev_select.c (file contents):
Revision 1.14 by root, Tue Nov 6 00:10:04 2007 UTC vs.
Revision 1.40 by root, Tue Jan 6 19:46:56 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;
49 int mask = 1 << (fd & 7);
50
51 if (oev == nev) 70 if (oev == nev)
52 return; 71 return;
53 72
54 if (vec_max < (fd >> 5) + 1) 73 {
74#if EV_SELECT_USE_FD_SET
75 assert (("libev: fd >= FD_SETSIZE passed to fd_set-based select backend", fd < FD_SETSIZE));
76
77 #if EV_SELECT_IS_WINSOCKET
78 SOCKET handle = anfds [fd].handle;
79 #else
80 int handle = fd;
81 #endif
82
83 /* FD_SET is broken on windows (it adds the fd to a set twice or more,
84 * which eventually leads to overflows). Need to call it only on changes.
85 */
86 #if EV_SELECT_IS_WINSOCKET
87 if ((oev ^ nev) & EV_READ)
88 #endif
89 if (nev & EV_READ)
90 FD_SET (handle, (fd_set *)vec_ri);
91 else
92 FD_CLR (handle, (fd_set *)vec_ri);
93
94 #if EV_SELECT_IS_WINSOCKET
95 if ((oev ^ nev) & EV_WRITE)
96 #endif
97 if (nev & EV_WRITE)
98 FD_SET (handle, (fd_set *)vec_wi);
99 else
100 FD_CLR (handle, (fd_set *)vec_wi);
101
102#else
103
104 int word = fd / NFDBITS;
105 fd_mask mask = 1UL << (fd % NFDBITS);
106
107 if (expect_false (vec_max <= word))
55 { 108 {
56 int new_max = (fd >> 5) + 1; 109 int new_max = word + 1;
57 110
58 vec_ri = (unsigned char *)ev_realloc (vec_ri, new_max * 4); 111 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
59 vec_ro = (unsigned char *)ev_realloc (vec_ro, new_max * 4); /* could free/malloc */ 112 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
60 vec_wi = (unsigned char *)ev_realloc (vec_wi, new_max * 4); 113 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
61 vec_wo = (unsigned char *)ev_realloc (vec_wo, new_max * 4); /* could free/malloc */ 114 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
115 #ifdef _WIN32
116 vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
117 #endif
62 118
63 for (; vec_max < new_max; ++vec_max) 119 for (; vec_max < new_max; ++vec_max)
64 ((uint32_t *)vec_ri)[vec_max] = 120 ((fd_mask *)vec_ri) [vec_max] =
65 ((uint32_t *)vec_wi)[vec_max] = 0; 121 ((fd_mask *)vec_wi) [vec_max] = 0;
66 } 122 }
67 123
68 vec_ri [offs] |= mask; 124 ((fd_mask *)vec_ri) [word] |= mask;
69 if (!(nev & EV_READ)) 125 if (!(nev & EV_READ))
70 vec_ri [offs] &= ~mask; 126 ((fd_mask *)vec_ri) [word] &= ~mask;
71 127
72 vec_wi [offs] |= mask; 128 ((fd_mask *)vec_wi) [word] |= mask;
73 if (!(nev & EV_WRITE)) 129 if (!(nev & EV_WRITE))
74 vec_wi [offs] &= ~mask; 130 ((fd_mask *)vec_wi) [word] &= ~mask;
131#endif
132 }
75} 133}
76 134
77static void 135static void
78select_poll (EV_P_ ev_tstamp timeout) 136select_poll (EV_P_ ev_tstamp timeout)
79{ 137{
80 int word, offs;
81 struct timeval tv; 138 struct timeval tv;
82 int res; 139 int res;
83 140 int fd_setsize;
84 memcpy (vec_ro, vec_ri, vec_max * 4);
85 memcpy (vec_wo, vec_wi, vec_max * 4);
86 141
87 tv.tv_sec = (long)timeout; 142 tv.tv_sec = (long)timeout;
88 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 143 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
89 144
145#if EV_SELECT_USE_FD_SET
146 fd_setsize = sizeof (fd_set);
147#else
148 fd_setsize = vec_max * NFDBYTES;
149#endif
150
151 memcpy (vec_ro, vec_ri, fd_setsize);
152 memcpy (vec_wo, vec_wi, fd_setsize);
153
154#ifdef _WIN32
155 /* pass in the write set as except set.
156 * the idea behind this is to work around a windows bug that causes
157 * errors to be reported as an exception and not by setting
158 * the writable bit. this is so uncontrollably lame.
159 */
160 memcpy (vec_eo, vec_wi, fd_setsize);
161 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
162#elif EV_SELECT_USE_FD_SET
163 fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
164 res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
165#else
90 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 166 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
167#endif
91 168
92 if (res < 0) 169 if (expect_false (res < 0))
93 { 170 {
171 #if EV_SELECT_IS_WINSOCKET
172 errno = WSAGetLastError ();
173 #endif
174 #ifdef WSABASEERR
175 /* on windows, select returns incompatible error codes, fix this */
176 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
177 if (errno == WSAENOTSOCK)
178 errno = EBADF;
179 else
180 errno -= WSABASEERR;
181 #endif
182
183 #ifdef _WIN32
184 /* select on windows errornously returns EINVAL when no fd sets have been
185 * provided (this is documented). what microsoft doesn't tell you that this bug
186 * exists even when the fd sets _are_ provided, so we have to check for this bug
187 * here and emulate by sleeping manually.
188 * we also get EINVAL when the timeout is invalid, but we ignore this case here
189 * and assume that EINVAL always means: you have to wait manually.
190 */
191 if (errno == EINVAL)
192 {
193 ev_sleep (timeout);
194 return;
195 }
196 #endif
197
94 if (errno == EBADF) 198 if (errno == EBADF)
95 fd_ebadf (EV_A); 199 fd_ebadf (EV_A);
96 else if (errno == ENOMEM && !syserr_cb) 200 else if (errno == ENOMEM && !syserr_cb)
97 fd_enomem (EV_A); 201 fd_enomem (EV_A);
98 else if (errno != EINTR) 202 else if (errno != EINTR)
99 syserr (); 203 ev_syserr ("(libev) select");
100 204
101 return; 205 return;
102 } 206 }
103 207
208#if EV_SELECT_USE_FD_SET
209
210 {
211 int fd;
212
213 for (fd = 0; fd < anfdmax; ++fd)
214 if (anfds [fd].events)
215 {
216 int events = 0;
217 #if EV_SELECT_IS_WINSOCKET
218 SOCKET handle = anfds [fd].handle;
219 #else
220 int handle = fd;
221 #endif
222
223 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
224 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
225 #ifdef _WIN32
226 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
227 #endif
228
229 if (expect_true (events))
230 fd_event (EV_A_ fd, events);
231 }
232 }
233
234#else
235
236 {
237 int word, bit;
104 for (word = vec_max; word--; ) 238 for (word = vec_max; word--; )
105 { 239 {
106 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 240 fd_mask word_r = ((fd_mask *)vec_ro) [word];
107 for (offs = 4; offs--; ) 241 fd_mask word_w = ((fd_mask *)vec_wo) [word];
242 #ifdef _WIN32
243 word_w |= ((fd_mask *)vec_eo) [word];
244 #endif
245
246 if (word_r || word_w)
247 for (bit = NFDBITS; bit--; )
108 { 248 {
109 int idx = word * 4 + offs; 249 fd_mask mask = 1UL << bit;
110 unsigned char byte_r = vec_ro [idx];
111 unsigned char byte_w = vec_wo [idx];
112 int bit;
113
114 if (byte_r | byte_w)
115 for (bit = 8; bit--; )
116 {
117 int events = 0; 250 int events = 0;
251
118 events |= byte_r & (1 << bit) ? EV_READ : 0; 252 events |= word_r & mask ? EV_READ : 0;
119 events |= byte_w & (1 << bit) ? EV_WRITE : 0; 253 events |= word_w & mask ? EV_WRITE : 0;
120 254
121 if (events) 255 if (expect_true (events))
122 fd_event (EV_A_ idx * 8 + bit, events); 256 fd_event (EV_A_ word * NFDBITS + bit, events);
123 }
124 } 257 }
125 } 258 }
126} 259 }
127 260
128static int 261#endif
262}
263
264int inline_size
129select_init (EV_P_ int flags) 265select_init (EV_P_ int flags)
130{ 266{
131 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 267 backend_fudge = 0.; /* posix says this is zero */
132 method_modify = select_modify; 268 backend_modify = select_modify;
133 method_poll = select_poll; 269 backend_poll = select_poll;
134 270
271#if EV_SELECT_USE_FD_SET
272 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
273 vec_ro = ev_malloc (sizeof (fd_set));
274 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
275 vec_wo = ev_malloc (sizeof (fd_set));
276 #ifdef _WIN32
277 vec_eo = ev_malloc (sizeof (fd_set));
278 #endif
279#else
135 vec_max = 0; 280 vec_max = 0;
136 vec_ri = 0; 281 vec_ri = 0;
137 vec_ri = 0; 282 vec_ri = 0;
138 vec_wo = 0; 283 vec_wo = 0;
139 vec_wo = 0; 284 vec_wo = 0;
285#endif
140 286
141 return EVMETHOD_SELECT; 287 return EVBACKEND_SELECT;
142} 288}
143 289
144static void 290void inline_size
145select_destroy (EV_P) 291select_destroy (EV_P)
146{ 292{
147 ev_free (vec_ri); 293 ev_free (vec_ri);
148 ev_free (vec_ro); 294 ev_free (vec_ro);
149 ev_free (vec_wi); 295 ev_free (vec_wi);

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