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Comparing libev/ev_select.c (file contents):
Revision 1.3 by root, Wed Oct 31 00:24:16 2007 UTC vs.
Revision 1.36 by root, Wed Jun 4 07:42:58 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# undef NFDBITS
58# define NFDBITS 0
59#endif
60
61#if !EV_SELECT_USE_FD_SET
62# define NFDBYTES (NFDBITS / 8)
63#endif
8 64
9#include <string.h> 65#include <string.h>
10#include <inttypes.h>
11
12static unsigned char *vec_ri, *vec_ro, *vec_wi, *vec_wo;
13static int vec_max;
14 66
15static void 67static void
16select_modify (int fd, int oev, int nev) 68select_modify (EV_P_ int fd, int oev, int nev)
17{ 69{
18 int offs = fd >> 3; 70 if (oev == nev)
19 int mask = 1 << (fd & 7); 71 return;
20 72
21 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))
22 { 98 {
23 vec_max = (fd >> 5) + 1; 99 int new_max = word + 1;
24 100
25 vec_ri = (unsigned char *)realloc (vec_ri, vec_max * 4); 101 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
26 vec_ro = (unsigned char *)realloc (vec_ro, vec_max * 4); /* could free/malloc */ 102 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
27 vec_wi = (unsigned char *)realloc (vec_wi, vec_max * 4); 103 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
28 vec_wo = (unsigned char *)realloc (vec_wo, vec_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
108
109 for (; vec_max < new_max; ++vec_max)
110 ((fd_mask *)vec_ri) [vec_max] =
111 ((fd_mask *)vec_wi) [vec_max] = 0;
29 } 112 }
30 113
31 vec_ri [offs] |= mask; 114 ((fd_mask *)vec_ri) [word] |= mask;
32 if (!(nev & EV_READ)) 115 if (!(nev & EV_READ))
33 vec_ri [offs] &= ~mask; 116 ((fd_mask *)vec_ri) [word] &= ~mask;
34 117
35 vec_wi [offs] |= mask; 118 ((fd_mask *)vec_wi) [word] |= mask;
36 if (!(nev & EV_WRITE)) 119 if (!(nev & EV_WRITE))
37 vec_wi [offs] &= ~mask; 120 ((fd_mask *)vec_wi) [word] &= ~mask;
121#endif
122 }
38} 123}
39 124
125static void
40static void select_poll (ev_tstamp timeout) 126select_poll (EV_P_ ev_tstamp timeout)
41{ 127{
42 struct timeval tv; 128 struct timeval tv;
43 int res; 129 int res;
44 130 int fd_setsize;
45 memcpy (vec_ro, vec_ri, vec_max * 4);
46 memcpy (vec_wo, vec_wi, vec_max * 4);
47 131
48 tv.tv_sec = (long)timeout; 132 tv.tv_sec = (long)timeout;
49 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 133 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
50 134
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
51 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
52 155
53 if (res > 0) 156 if (expect_false (res < 0))
54 { 157 {
55 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
56 169
57 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)
58 { 179 {
59 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 180 ev_sleep (timeout);
60 for (offs = 4; offs--; ) 181 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 } 182 }
183 #endif
184
185 if (errno == EBADF)
186 fd_ebadf (EV_A);
187 else if (errno == ENOMEM && !syserr_cb)
188 fd_enomem (EV_A);
189 else if (errno != EINTR)
190 syserr ("(libev) select");
191
192 return;
79 } 193 }
80}
81 194
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
82void select_init (int flags) 252select_init (EV_P_ int flags)
83{ 253{
84 ev_method = EVMETHOD_SELECT; 254 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; 255 backend_modify = select_modify;
87 method_poll = select_poll; 256 backend_poll = select_poll;
88}
89 257
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
90 274
275 return EVBACKEND_SELECT;
276}
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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