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Comparing libev/ev_select.c (file contents):
Revision 1.2 by root, Tue Oct 30 23:54:38 2007 UTC vs.
Revision 1.33 by root, Mon May 26 04:14:32 2008 UTC

1/* for broken bsd's */ 1/*
2#include <sys/time.h> 2 * libev select fd activity backend
3#include <sys/types.h> 3 *
4#include <unistd.h> 4 * Copyright (c) 2007,2008 Marc Alexander Lehmann <libev@schmorp.de>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without modifica-
8 * tion, are permitted provided that the following conditions are 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.
27 *
28 * Alternatively, the contents of this file may be used under the terms of
29 * the GNU General Public License ("GPL") version 2 or any later version,
30 * in which case the provisions of the GPL are applicable instead of
31 * the above. If you wish to allow the use of your version of this file
32 * only under the terms of the GPL and not to allow others to use your
33 * version of this file under the BSD license, indicate your decision
34 * by deleting the provisions above and replace them with the notice
35 * and other provisions required by the GPL. If you do not delete the
36 * provisions above, a recipient may use your version of this file under
37 * either the BSD or the GPL.
38 */
5 39
40#ifndef _WIN32
6/* for unix systems */ 41/* for unix systems */
7#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#endif
58
59#if !EV_SELECT_USE_FD_SET
60# define NFDBYTES (NFDBITS / 8)
61#endif
8 62
9#include <string.h> 63#include <string.h>
10#include <inttypes.h>
11
12static unsigned char *vec_ri, *vec_ro, *vec_wi, *vec_wo;
13static int vec_max;
14 64
15static void 65static void
16select_modify (int fd, int oev, int nev) 66select_modify (EV_P_ int fd, int oev, int nev)
17{ 67{
18 int offs = fd >> 3; 68 if (oev == nev)
19 int mask = 1 << (fd & 7); 69 return;
20 70
21 if (vec_max < (fd >> 5) + 1) 71 {
72#if EV_SELECT_USE_FD_SET
73
74 #if EV_SELECT_IS_WINSOCKET
75 SOCKET handle = anfds [fd].handle;
76 #else
77 int handle = fd;
78 #endif
79
80 if (nev & EV_READ)
81 FD_SET (handle, (fd_set *)vec_ri);
82 else
83 FD_CLR (handle, (fd_set *)vec_ri);
84
85 if (nev & EV_WRITE)
86 FD_SET (handle, (fd_set *)vec_wi);
87 else
88 FD_CLR (handle, (fd_set *)vec_wi);
89
90#else
91
92 int word = fd / NFDBITS;
93 fd_mask mask = 1UL << (fd % NFDBITS);
94
95 if (expect_false (vec_max <= word))
22 { 96 {
23 vec_max = (fd >> 5) + 1; 97 int new_max = word + 1;
24 98
25 vec_ri = (unsigned char *)realloc (vec_ri, vec_max * 4); 99 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
26 vec_ro = (unsigned char *)realloc (vec_ro, vec_max * 4); /* could free/malloc */ 100 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
27 vec_wi = (unsigned char *)realloc (vec_wi, vec_max * 4); 101 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
28 vec_wo = (unsigned char *)realloc (vec_wo, vec_max * 4); /* could free/malloc */ 102 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
103 #ifdef _WIN32
104 vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
105 #endif
106
107 for (; vec_max < new_max; ++vec_max)
108 ((fd_mask *)vec_ri) [vec_max] =
109 ((fd_mask *)vec_wi) [vec_max] = 0;
29 } 110 }
30 111
31 vec_ri [offs] |= mask; 112 ((fd_mask *)vec_ri) [word] |= mask;
32 if (!(nev & EV_READ)) 113 if (!(nev & EV_READ))
33 vec_ri [offs] &= ~mask; 114 ((fd_mask *)vec_ri) [word] &= ~mask;
34 115
35 vec_wi [offs] |= mask; 116 ((fd_mask *)vec_wi) [word] |= mask;
36 if (!(nev & EV_WRITE)) 117 if (!(nev & EV_WRITE))
37 vec_wi [offs] &= ~mask; 118 ((fd_mask *)vec_wi) [word] &= ~mask;
119#endif
120 }
38} 121}
39 122
123static void
40static void select_poll (ev_tstamp timeout) 124select_poll (EV_P_ ev_tstamp timeout)
41{ 125{
42 struct timeval tv; 126 struct timeval tv;
43 int res; 127 int res;
44 128 int fd_setsize;
45 memcpy (vec_ro, vec_ri, vec_max * 4);
46 memcpy (vec_wo, vec_wi, vec_max * 4);
47 129
48 tv.tv_sec = (long)timeout; 130 tv.tv_sec = (long)timeout;
49 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 131 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
50 132
133#if EV_SELECT_USE_FD_SET
134 fd_setsize = sizeof (fd_set);
135#else
136 fd_setsize = vec_max * NFDBYTES;
137#endif
138
139 memcpy (vec_ro, vec_ri, fd_setsize);
140 memcpy (vec_wo, vec_wi, fd_setsize);
141
142#ifdef _WIN32
143 /* pass in the write set as except set.
144 * the idea behind this is to work around a windows bug that causes
145 * errors to be reported as an exception and not by setting
146 * the writable bit. this is so uncontrollably lame.
147 */
148 memcpy (vec_eo, vec_wi, fd_setsize);
149 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
150#else
51 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 151 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
152#endif
52 153
53 if (res > 0) 154 if (expect_false (res < 0))
54 { 155 {
55 int word, offs; 156 #if EV_SELECT_IS_WINSOCKET
157 errno = WSAGetLastError ();
158 #endif
159 #ifdef WSABASEERR
160 /* on windows, select returns incompatible error codes, fix this */
161 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
162 if (errno == WSAENOTSOCK)
163 errno = EBADF;
164 else
165 errno -= WSABASEERR;
166 #endif
56 167
57 for (word = vec_max; word--; ) 168 #ifdef _WIN32
169 /* select on windows errornously returns EINVAL when no fd sets have been
170 * provided (this is documented). what microsoft doesn't tell you that this bug
171 * exists even when the fd sets are provided, so we have to check for this bug
172 * here and emulate by sleeping manually.
173 * we also get EINVAL when the timeout is invalid, but we ignore this case here
174 * and assume that EINVAL always means: you have to wait manually.
175 */
176 if (errno == EINVAL)
58 { 177 {
59 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 178 ev_sleep (timeout);
60 for (offs = 4; offs--; ) 179 return;
61 {
62 int idx = word * 4 + offs;
63 unsigned char byte_r = vec_ro [idx];
64 unsigned char byte_w = vec_wo [idx];
65 int bit;
66
67 if (byte_r | byte_w)
68 for (bit = 8; bit--; )
69 {
70 int events = 0;
71 events |= byte_r & (1 << bit) ? EV_READ : 0;
72 events |= byte_w & (1 << bit) ? EV_WRITE : 0;
73
74 if (events)
75 fd_event (idx * 8 + bit, events);
76 }
77 }
78 } 180 }
181 #endif
182
183 if (errno == EBADF)
184 fd_ebadf (EV_A);
185 else if (errno == ENOMEM && !syserr_cb)
186 fd_enomem (EV_A);
187 else if (errno != EINTR)
188 syserr ("(libev) select");
189
190 return;
79 } 191 }
80}
81 192
193#if EV_SELECT_USE_FD_SET
194
195 {
196 int fd;
197
198 for (fd = 0; fd < anfdmax; ++fd)
199 if (anfds [fd].events)
200 {
201 int events = 0;
202 #if EV_SELECT_IS_WINSOCKET
203 SOCKET handle = anfds [fd].handle;
204 #else
205 int handle = fd;
206 #endif
207
208 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
209 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
210 #ifdef _WIN32
211 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
212 #endif
213
214 if (expect_true (events))
215 fd_event (EV_A_ fd, events);
216 }
217 }
218
219#else
220
221 {
222 int word, bit;
223 for (word = vec_max; word--; )
224 {
225 fd_mask word_r = ((fd_mask *)vec_ro) [word];
226 fd_mask word_w = ((fd_mask *)vec_wo) [word];
227 #ifdef _WIN32
228 word_w |= ((fd_mask *)vec_eo) [word];
229 #endif
230
231 if (word_r || word_w)
232 for (bit = NFDBITS; bit--; )
233 {
234 fd_mask mask = 1UL << bit;
235 int events = 0;
236
237 events |= word_r & mask ? EV_READ : 0;
238 events |= word_w & mask ? EV_WRITE : 0;
239
240 if (expect_true (events))
241 fd_event (EV_A_ word * NFDBITS + bit, events);
242 }
243 }
244 }
245
246#endif
247}
248
249int inline_size
82int select_init (int flags) 250select_init (EV_P_ int flags)
83{ 251{
84 ev_method = EVMETHOD_SELECT; 252 backend_fudge = 0.; /* posix says this is zero */
85 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */
86 method_modify = select_modify; 253 backend_modify = select_modify;
87 method_poll = select_poll; 254 backend_poll = select_poll;
88 255
89 return 1; 256#if EV_SELECT_USE_FD_SET
90} 257 vec_max = FD_SETSIZE / 32;
258 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
259 vec_ro = ev_malloc (sizeof (fd_set));
260 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
261 vec_wo = ev_malloc (sizeof (fd_set));
262 #ifdef _WIN32
263 vec_eo = ev_malloc (sizeof (fd_set));
264 #endif
265#else
266 vec_max = 0;
267 vec_ri = 0;
268 vec_ri = 0;
269 vec_wo = 0;
270 vec_wo = 0;
271#endif
91 272
273 return EVBACKEND_SELECT;
274}
92 275
276void inline_size
277select_destroy (EV_P)
278{
279 ev_free (vec_ri);
280 ev_free (vec_ro);
281 ev_free (vec_wi);
282 ev_free (vec_wo);
283}
284
285

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