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Comparing libev/ev_select.c (file contents):
Revision 1.17 by root, Tue Nov 6 16:09:37 2007 UTC vs.
Revision 1.51 by root, Mon Jan 31 00:49:26 2011 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) 2007,2008,2009,2010 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
40#ifndef _WIN32
32/* for unix systems */ 41/* for unix systems */
33#ifdef WIN32 42# include <inttypes.h>
34typedef unsigned int uint32_t; 43# ifndef __hpux
44/* for REAL unix systems */
45# include <sys/select.h>
46# endif
47#endif
48
49#ifndef EV_SELECT_USE_FD_SET
50# ifdef NFDBITS
51# define EV_SELECT_USE_FD_SET 0
52# else
53# define EV_SELECT_USE_FD_SET 1
54# endif
55#endif
56
57#if EV_SELECT_IS_WINSOCKET
58# undef EV_SELECT_USE_FD_SET
35# define EV_SELECT_USE_FD_SET 1 59# define EV_SELECT_USE_FD_SET 1
36#else 60# undef NFDBITS
37# include <sys/select.h> 61# define NFDBITS 0
38# include <inttypes.h> 62#endif
63
64#if !EV_SELECT_USE_FD_SET
65# define NFDBYTES (NFDBITS / 8)
39#endif 66#endif
40 67
41#include <string.h> 68#include <string.h>
42 69
43static void 70static void
44select_modify (EV_P_ int fd, int oev, int nev) 71select_modify (EV_P_ int fd, int oev, int nev)
45{ 72{
46 if (oev == nev) 73 if (oev == nev)
47 return; 74 return;
48 75
76 {
49#if EV_SELECT_USE_FD_SET 77#if EV_SELECT_USE_FD_SET
78
79 #if EV_SELECT_IS_WINSOCKET
80 SOCKET handle = anfds [fd].handle;
81 #else
82 int handle = fd;
83 #endif
84
85 assert (("libev: fd >= FD_SETSIZE passed to fd_set-based select backend", fd < FD_SETSIZE));
86
87 /* FD_SET is broken on windows (it adds the fd to a set twice or more,
88 * which eventually leads to overflows). Need to call it only on changes.
89 */
90 #if EV_SELECT_IS_WINSOCKET
91 if ((oev ^ nev) & EV_READ)
92 #endif
50 if (nev & EV_READ) 93 if (nev & EV_READ)
51 FD_SET (fd, (struct fd_set *)vec_ri); 94 FD_SET (handle, (fd_set *)vec_ri);
52 else 95 else
53 FD_CLR (fd, (struct fd_set *)vec_ri); 96 FD_CLR (handle, (fd_set *)vec_ri);
54 97
98 #if EV_SELECT_IS_WINSOCKET
99 if ((oev ^ nev) & EV_WRITE)
100 #endif
55 if (nev & EV_WRITE) 101 if (nev & EV_WRITE)
56 FD_SET (fd, (struct fd_set *)vec_wi); 102 FD_SET (handle, (fd_set *)vec_wi);
57 else 103 else
58 FD_CLR (fd, (struct fd_set *)vec_wi); 104 FD_CLR (handle, (fd_set *)vec_wi);
59#else
60 {
61 int offs = fd >> 3;
62 int mask = 1 << (fd & 7);
63 105
64 if (vec_max < (fd >> 5) + 1) 106#else
107
108 int word = fd / NFDBITS;
109 fd_mask mask = 1UL << (fd % NFDBITS);
110
111 if (expect_false (vec_max <= word))
65 { 112 {
66 int new_max = (fd >> 5) + 1; 113 int new_max = word + 1;
67 114
68 vec_ri = (unsigned char *)ev_realloc (vec_ri, new_max * 4); 115 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
69 vec_ro = (unsigned char *)ev_realloc (vec_ro, new_max * 4); /* could free/malloc */ 116 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
70 vec_wi = (unsigned char *)ev_realloc (vec_wi, new_max * 4); 117 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
71 vec_wo = (unsigned char *)ev_realloc (vec_wo, new_max * 4); /* could free/malloc */ 118 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
119 #ifdef _WIN32
120 vec_eo = ev_realloc (vec_eo, new_max * NFDBYTES); /* could free/malloc */
121 #endif
72 122
73 for (; vec_max < new_max; ++vec_max) 123 for (; vec_max < new_max; ++vec_max)
74 ((uint32_t *)vec_ri)[vec_max] = 124 ((fd_mask *)vec_ri) [vec_max] =
75 ((uint32_t *)vec_wi)[vec_max] = 0; 125 ((fd_mask *)vec_wi) [vec_max] = 0;
76 } 126 }
77 127
78 vec_ri [offs] |= mask; 128 ((fd_mask *)vec_ri) [word] |= mask;
79 if (!(nev & EV_READ)) 129 if (!(nev & EV_READ))
80 vec_ri [offs] &= ~mask; 130 ((fd_mask *)vec_ri) [word] &= ~mask;
81 131
82 vec_wi [offs] |= mask; 132 ((fd_mask *)vec_wi) [word] |= mask;
83 if (!(nev & EV_WRITE)) 133 if (!(nev & EV_WRITE))
84 vec_wi [offs] &= ~mask; 134 ((fd_mask *)vec_wi) [word] &= ~mask;
135#endif
85 } 136 }
86#endif
87} 137}
88 138
89static void 139static void
90select_poll (EV_P_ ev_tstamp timeout) 140select_poll (EV_P_ ev_tstamp timeout)
91{ 141{
92 int word, offs;
93 struct timeval tv; 142 struct timeval tv;
94 int res; 143 int res;
144 int fd_setsize;
145
146 EV_RELEASE_CB;
147 EV_TV_SET (tv, timeout);
95 148
96#if EV_SELECT_USE_FD_SET 149#if EV_SELECT_USE_FD_SET
150 fd_setsize = sizeof (fd_set);
151#else
152 fd_setsize = vec_max * NFDBYTES;
153#endif
154
97 memcpy (vec_ro, vec_ri, sizeof (struct fd_set)); 155 memcpy (vec_ro, vec_ri, fd_setsize);
98 memcpy (vec_wo, vec_wi, sizeof (struct fd_set)); 156 memcpy (vec_wo, vec_wi, fd_setsize);
99#else
100 memcpy (vec_ro, vec_ri, vec_max * 4);
101 memcpy (vec_wo, vec_wi, vec_max * 4);
102#endif
103 157
104 tv.tv_sec = (long)timeout; 158#ifdef _WIN32
105 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 159 /* pass in the write set as except set.
106 160 * the idea behind this is to work around a windows bug that causes
161 * errors to be reported as an exception and not by setting
162 * the writable bit. this is so uncontrollably lame.
163 */
164 memcpy (vec_eo, vec_wi, fd_setsize);
165 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, (fd_set *)vec_eo, &tv);
166#elif EV_SELECT_USE_FD_SET
167 fd_setsize = anfdmax < FD_SETSIZE ? anfdmax : FD_SETSIZE;
168 res = select (fd_setsize, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
169#else
107 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 170 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
171#endif
172 EV_ACQUIRE_CB;
108 173
109 if (res < 0) 174 if (expect_false (res < 0))
110 { 175 {
111#ifdef WIN32 176 #if EV_SELECT_IS_WINSOCKET
112 if (errno == WSAEINTR ) errno = EINTR; 177 errno = WSAGetLastError ();
178 #endif
179 #ifdef WSABASEERR
180 /* on windows, select returns incompatible error codes, fix this */
181 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
113 if (errno == WSAENOTSOCK) errno = EBADF; 182 if (errno == WSAENOTSOCK)
114#endif 183 errno = EBADF;
184 else
185 errno -= WSABASEERR;
186 #endif
187
188 #ifdef _WIN32
189 /* select on windows erroneously returns EINVAL when no fd sets have been
190 * provided (this is documented). what microsoft doesn't tell you that this bug
191 * exists even when the fd sets _are_ provided, so we have to check for this bug
192 * here and emulate by sleeping manually.
193 * we also get EINVAL when the timeout is invalid, but we ignore this case here
194 * and assume that EINVAL always means: you have to wait manually.
195 */
196 if (errno == EINVAL)
197 {
198 ev_sleep (timeout);
199 return;
200 }
201 #endif
115 202
116 if (errno == EBADF) 203 if (errno == EBADF)
117 fd_ebadf (EV_A); 204 fd_ebadf (EV_A);
118 else if (errno == ENOMEM && !syserr_cb) 205 else if (errno == ENOMEM && !syserr_cb)
119 fd_enomem (EV_A); 206 fd_enomem (EV_A);
120 else if (errno != EINTR) 207 else if (errno != EINTR)
121 syserr ("(libev) select"); 208 ev_syserr ("(libev) select");
122 209
123 return; 210 return;
124 } 211 }
125 212
126#if EV_SELECT_USE_FD_SET 213#if EV_SELECT_USE_FD_SET
127 for (word = 0; word < FD_SETSIZE; ++word) 214
128 { 215 {
216 int fd;
217
218 for (fd = 0; fd < anfdmax; ++fd)
219 if (anfds [fd].events)
220 {
129 int events = 0; 221 int events = 0;
222 #if EV_SELECT_IS_WINSOCKET
223 SOCKET handle = anfds [fd].handle;
224 #else
225 int handle = fd;
226 #endif
227
130 if (FD_ISSET (word, (struct fd_set *)vec_ro)) events |= EV_READ; 228 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
131 if (FD_ISSET (word, (struct fd_set *)vec_wo)) events |= EV_WRITE; 229 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
230 #ifdef _WIN32
231 if (FD_ISSET (handle, (fd_set *)vec_eo)) events |= EV_WRITE;
232 #endif
132 233
133 if (events) 234 if (expect_true (events))
134 fd_event (EV_A_ word, events); 235 fd_event (EV_A_ fd, events);
236 }
135 } 237 }
238
136#else 239#else
240
241 {
242 int word, bit;
137 for (word = vec_max; word--; ) 243 for (word = vec_max; word--; )
138 { 244 {
139 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 245 fd_mask word_r = ((fd_mask *)vec_ro) [word];
140 for (offs = 4; offs--; ) 246 fd_mask word_w = ((fd_mask *)vec_wo) [word];
247 #ifdef _WIN32
248 word_w |= ((fd_mask *)vec_eo) [word];
249 #endif
250
251 if (word_r || word_w)
252 for (bit = NFDBITS; bit--; )
141 { 253 {
142 int idx = word * 4 + offs; 254 fd_mask mask = 1UL << bit;
143 unsigned char byte_r = vec_ro [idx];
144 unsigned char byte_w = vec_wo [idx];
145 int bit;
146
147 if (byte_r | byte_w)
148 for (bit = 8; bit--; )
149 {
150 int events = 0; 255 int events = 0;
256
151 events |= byte_r & (1 << bit) ? EV_READ : 0; 257 events |= word_r & mask ? EV_READ : 0;
152 events |= byte_w & (1 << bit) ? EV_WRITE : 0; 258 events |= word_w & mask ? EV_WRITE : 0;
153 259
154 if (events) 260 if (expect_true (events))
155 fd_event (EV_A_ idx * 8 + bit, events); 261 fd_event (EV_A_ word * NFDBITS + bit, events);
156 }
157 } 262 }
158 } 263 }
264 }
265
159#endif 266#endif
160} 267}
161 268
162static int 269int inline_size
163select_init (EV_P_ int flags) 270select_init (EV_P_ int flags)
164{ 271{
165 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 272 backend_fudge = 0.; /* posix says this is zero */
166 method_modify = select_modify; 273 backend_modify = select_modify;
167 method_poll = select_poll; 274 backend_poll = select_poll;
168 275
169#if EV_SELECT_USE_FD_SET 276#if EV_SELECT_USE_FD_SET
170 vec_max = FD_SETSIZE / 32;
171 vec_ri = ev_malloc (sizeof (struct fd_set)); FD_ZERO ((struct fd_set *)vec_ri); 277 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
172 vec_ro = ev_malloc (sizeof (struct fd_set)); 278 vec_ro = ev_malloc (sizeof (fd_set));
173 vec_wi = ev_malloc (sizeof (struct fd_set)); FD_ZERO ((struct fd_set *)vec_wi); 279 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
174 vec_wo = ev_malloc (sizeof (struct fd_set)); 280 vec_wo = ev_malloc (sizeof (fd_set));
281 #ifdef _WIN32
282 vec_eo = ev_malloc (sizeof (fd_set));
283 #endif
175#else 284#else
176 vec_max = 0; 285 vec_max = 0;
177 vec_ri = 0; 286 vec_ri = 0;
178 vec_ri = 0; 287 vec_ro = 0;
288 vec_wi = 0;
179 vec_wo = 0; 289 vec_wo = 0;
290 #ifdef _WIN32
180 vec_wo = 0; 291 vec_eo = 0;
181#endif 292 #endif
293#endif
182 294
183 return EVMETHOD_SELECT; 295 return EVBACKEND_SELECT;
184} 296}
185 297
186static void 298void inline_size
187select_destroy (EV_P) 299select_destroy (EV_P)
188{ 300{
189 ev_free (vec_ri); 301 ev_free (vec_ri);
190 ev_free (vec_ro); 302 ev_free (vec_ro);
191 ev_free (vec_wi); 303 ev_free (vec_wi);
192 ev_free (vec_wo); 304 ev_free (vec_wo);
305 #ifdef _WIN32
306 ev_free (vec_eo);
307 #endif
193} 308}
194 309
195 310

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