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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 1.36 by root, Wed Jun 4 07:42:58 2008 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 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 if (nev & EV_READ)
83 FD_SET (handle, (fd_set *)vec_ri);
84 else
85 FD_CLR (handle, (fd_set *)vec_ri);
86
87 if (nev & EV_WRITE)
88 FD_SET (handle, (fd_set *)vec_wi);
89 else
90 FD_CLR (handle, (fd_set *)vec_wi);
91
92#else
93
94 int word = fd / NFDBITS;
95 fd_mask mask = 1UL << (fd % NFDBITS);
96
97 if (expect_false (vec_max <= word))
52 { 98 {
53 int new_max = (fd >> 5) + 1; 99 int new_max = word + 1;
54 100
55 vec_ri = (unsigned char *)realloc (vec_ri, new_max * 4); 101 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
56 vec_ro = (unsigned char *)realloc (vec_ro, new_max * 4); /* could free/malloc */ 102 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
57 vec_wi = (unsigned char *)realloc (vec_wi, new_max * 4); 103 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
58 vec_wo = (unsigned char *)realloc (vec_wo, new_max * 4); /* could free/malloc */ 104 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
105 #ifdef _WIN32
106 vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
107 #endif
59 108
60 for (; vec_max < new_max; ++vec_max) 109 for (; vec_max < new_max; ++vec_max)
61 ((uint32_t *)vec_ri)[vec_max] = 110 ((fd_mask *)vec_ri) [vec_max] =
62 ((uint32_t *)vec_wi)[vec_max] = 0; 111 ((fd_mask *)vec_wi) [vec_max] = 0;
63 } 112 }
64 113
65 vec_ri [offs] |= mask; 114 ((fd_mask *)vec_ri) [word] |= mask;
66 if (!(nev & EV_READ)) 115 if (!(nev & EV_READ))
67 vec_ri [offs] &= ~mask; 116 ((fd_mask *)vec_ri) [word] &= ~mask;
68 117
69 vec_wi [offs] |= mask; 118 ((fd_mask *)vec_wi) [word] |= mask;
70 if (!(nev & EV_WRITE)) 119 if (!(nev & EV_WRITE))
71 vec_wi [offs] &= ~mask; 120 ((fd_mask *)vec_wi) [word] &= ~mask;
121#endif
122 }
72} 123}
73 124
74static void 125static void
75select_poll (EV_P_ ev_tstamp timeout) 126select_poll (EV_P_ ev_tstamp timeout)
76{ 127{
77 struct timeval tv; 128 struct timeval tv;
78 int res; 129 int res;
79 130 int fd_setsize;
80 memcpy (vec_ro, vec_ri, vec_max * 4);
81 memcpy (vec_wo, vec_wi, vec_max * 4);
82 131
83 tv.tv_sec = (long)timeout; 132 tv.tv_sec = (long)timeout;
84 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 133 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
85 134
135#if EV_SELECT_USE_FD_SET
136 fd_setsize = sizeof (fd_set);
137#else
138 fd_setsize = vec_max * NFDBYTES;
139#endif
140
141 memcpy (vec_ro, vec_ri, fd_setsize);
142 memcpy (vec_wo, vec_wi, fd_setsize);
143
144#ifdef _WIN32
145 /* pass in the write set as except set.
146 * the idea behind this is to work around a windows bug that causes
147 * errors to be reported as an exception and not by setting
148 * the writable bit. this is so uncontrollably lame.
149 */
150 memcpy (vec_eo, vec_wi, fd_setsize);
151 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
152#else
86 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 153 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
154#endif
87 155
88 if (res > 0) 156 if (expect_false (res < 0))
89 { 157 {
90 int word, offs; 158 #if EV_SELECT_IS_WINSOCKET
159 errno = WSAGetLastError ();
160 #endif
161 #ifdef WSABASEERR
162 /* on windows, select returns incompatible error codes, fix this */
163 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
164 if (errno == WSAENOTSOCK)
165 errno = EBADF;
166 else
167 errno -= WSABASEERR;
168 #endif
91 169
92 for (word = vec_max; word--; ) 170 #ifdef _WIN32
171 /* select on windows errornously returns EINVAL when no fd sets have been
172 * provided (this is documented). what microsoft doesn't tell you that this bug
173 * exists even when the fd sets are provided, so we have to check for this bug
174 * here and emulate by sleeping manually.
175 * we also get EINVAL when the timeout is invalid, but we ignore this case here
176 * and assume that EINVAL always means: you have to wait manually.
177 */
178 if (errno == EINVAL)
93 { 179 {
94 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 180 ev_sleep (timeout);
95 for (offs = 4; offs--; ) 181 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 } 182 }
114 } 183 #endif
115 else if (res < 0) 184
116 {
117 if (errno == EBADF) 185 if (errno == EBADF)
118 fd_ebadf (EV_A); 186 fd_ebadf (EV_A);
119 else if (errno == ENOMEM) 187 else if (errno == ENOMEM && !syserr_cb)
120 fd_enomem (EV_A); 188 fd_enomem (EV_A);
189 else if (errno != EINTR)
190 syserr ("(libev) select");
191
192 return;
121 } 193 }
122}
123 194
124static int 195#if EV_SELECT_USE_FD_SET
196
197 {
198 int fd;
199
200 for (fd = 0; fd < anfdmax; ++fd)
201 if (anfds [fd].events)
202 {
203 int events = 0;
204 #if EV_SELECT_IS_WINSOCKET
205 SOCKET handle = anfds [fd].handle;
206 #else
207 int handle = fd;
208 #endif
209
210 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
211 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
212 #ifdef _WIN32
213 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
214 #endif
215
216 if (expect_true (events))
217 fd_event (EV_A_ fd, events);
218 }
219 }
220
221#else
222
223 {
224 int word, bit;
225 for (word = vec_max; word--; )
226 {
227 fd_mask word_r = ((fd_mask *)vec_ro) [word];
228 fd_mask word_w = ((fd_mask *)vec_wo) [word];
229 #ifdef _WIN32
230 word_w |= ((fd_mask *)vec_eo) [word];
231 #endif
232
233 if (word_r || word_w)
234 for (bit = NFDBITS; bit--; )
235 {
236 fd_mask mask = 1UL << bit;
237 int events = 0;
238
239 events |= word_r & mask ? EV_READ : 0;
240 events |= word_w & mask ? EV_WRITE : 0;
241
242 if (expect_true (events))
243 fd_event (EV_A_ word * NFDBITS + bit, events);
244 }
245 }
246 }
247
248#endif
249}
250
251int inline_size
125select_init (EV_P_ int flags) 252select_init (EV_P_ int flags)
126{ 253{
127 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 254 backend_fudge = 0.; /* posix says this is zero */
128 method_modify = select_modify; 255 backend_modify = select_modify;
129 method_poll = select_poll; 256 backend_poll = select_poll;
130 257
258#if EV_SELECT_USE_FD_SET
259 vec_max = FD_SETSIZE / 32;
260 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
261 vec_ro = ev_malloc (sizeof (fd_set));
262 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
263 vec_wo = ev_malloc (sizeof (fd_set));
264 #ifdef _WIN32
265 vec_eo = ev_malloc (sizeof (fd_set));
266 #endif
267#else
268 vec_max = 0;
269 vec_ri = 0;
270 vec_ri = 0;
271 vec_wo = 0;
272 vec_wo = 0;
273#endif
274
131 return EVMETHOD_SELECT; 275 return EVBACKEND_SELECT;
132} 276}
133 277
278void inline_size
279select_destroy (EV_P)
280{
281 ev_free (vec_ri);
282 ev_free (vec_ro);
283 ev_free (vec_wi);
284 ev_free (vec_wo);
285}
286
287

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