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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 1.30 by root, Thu May 22 14:05:14 2008 UTC

… …
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 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#endif
58
59#if !EV_SELECT_USE_FD_SET
60# define NFDBYTES (NFDBITS / 8)
40#endif 61#endif
41 62
42#include <string.h> 63#include <string.h>
43#include <inttypes.h>
44 64
45static void 65static void
46select_modify (EV_P_ int fd, int oev, int nev) 66select_modify (EV_P_ int fd, int oev, int nev)
47{ 67{
48 int offs = fd >> 3; 68 if (oev == nev)
49 int mask = 1 << (fd & 7); 69 return;
50 70
51 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))
52 { 96 {
53 int new_max = (fd >> 5) + 1; 97 int new_max = word + 1;
54 98
55 vec_ri = (unsigned char *)realloc (vec_ri, new_max * 4); 99 vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
56 vec_ro = (unsigned char *)realloc (vec_ro, new_max * 4); /* could free/malloc */ 100 vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
57 vec_wi = (unsigned char *)realloc (vec_wi, new_max * 4); 101 vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
58 vec_wo = (unsigned char *)realloc (vec_wo, new_max * 4); /* could free/malloc */ 102 vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
59 103
60 for (; vec_max < new_max; ++vec_max) 104 for (; vec_max < new_max; ++vec_max)
61 ((uint32_t *)vec_ri)[vec_max] = 105 ((fd_mask *)vec_ri) [vec_max] =
62 ((uint32_t *)vec_wi)[vec_max] = 0; 106 ((fd_mask *)vec_wi) [vec_max] = 0;
63 } 107 }
64 108
65 vec_ri [offs] |= mask; 109 ((fd_mask *)vec_ri) [word] |= mask;
66 if (!(nev & EV_READ)) 110 if (!(nev & EV_READ))
67 vec_ri [offs] &= ~mask; 111 ((fd_mask *)vec_ri) [word] &= ~mask;
68 112
69 vec_wi [offs] |= mask; 113 ((fd_mask *)vec_wi) [word] |= mask;
70 if (!(nev & EV_WRITE)) 114 if (!(nev & EV_WRITE))
71 vec_wi [offs] &= ~mask; 115 ((fd_mask *)vec_wi) [word] &= ~mask;
116#endif
117 }
72} 118}
73 119
74static void 120static void
75select_poll (EV_P_ ev_tstamp timeout) 121select_poll (EV_P_ ev_tstamp timeout)
76{ 122{
77 struct timeval tv; 123 struct timeval tv;
78 int res; 124 int res;
79 125
126#if EV_SELECT_USE_FD_SET
127 memcpy (vec_ro, vec_ri, sizeof (fd_set));
128 memcpy (vec_wo, vec_wi, sizeof (fd_set));
129#else
80 memcpy (vec_ro, vec_ri, vec_max * 4); 130 memcpy (vec_ro, vec_ri, vec_max * NFDBYTES);
81 memcpy (vec_wo, vec_wi, vec_max * 4); 131 memcpy (vec_wo, vec_wi, vec_max * NFDBYTES);
132#endif
82 133
83 tv.tv_sec = (long)timeout; 134 tv.tv_sec = (long)timeout;
84 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6); 135 tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
85 136
86 res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv); 137 res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
87 138
88 if (res > 0) 139 if (expect_false (res < 0))
89 { 140 {
90 int word, offs; 141 #if EV_SELECT_IS_WINSOCKET
142 errno = WSAGetLastError ();
143 #endif
144 #ifdef WSABASEERR
145 /* on windows, select returns incompatible error codes, fix this */
146 if (errno >= WSABASEERR && errno < WSABASEERR + 1000)
147 if (errno == WSAENOTSOCK)
148 errno = EBADF;
149 else
150 errno -= WSABASEERR;
151 #endif
91 152
92 for (word = vec_max; word--; ) 153 #ifdef _WIN32
154 /* select on windows errornously returns EINVAL when no fd sets have been
155 * provided (this is documented). what microsoft doesn't tell you that this bug
156 * exists even when the fd sets are provided, so we have to check for this bug
157 * here and emulate by sleeping manually.
158 * we also get EINVAL when the timeout is invalid, but we ignore this case here
159 * and assume that EINVAL always means: you have to wait manually.
160 */
161 if (errno == EINVAL)
93 { 162 {
94 if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word]) 163 ev_sleep (timeout);
95 for (offs = 4; offs--; ) 164 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 } 165 }
114 } 166 #endif
115 else if (res < 0) 167
116 {
117 if (errno == EBADF) 168 if (errno == EBADF)
118 fd_ebadf (EV_A); 169 fd_ebadf (EV_A);
119 else if (errno == ENOMEM) 170 else if (errno == ENOMEM && !syserr_cb)
120 fd_enomem (EV_A); 171 fd_enomem (EV_A);
172 else if (errno != EINTR)
173 syserr ("(libev) select");
174
175 return;
121 } 176 }
122}
123 177
124static int 178#if EV_SELECT_USE_FD_SET
179
180 {
181 int fd;
182
183 for (fd = 0; fd < anfdmax; ++fd)
184 if (anfds [fd].events)
185 {
186 int events = 0;
187 #if EV_SELECT_IS_WINSOCKET
188 SOCKET handle = anfds [fd].handle;
189 #else
190 int handle = fd;
191 #endif
192
193 if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
194 if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
195
196 if (expect_true (events))
197 fd_event (EV_A_ fd, events);
198 }
199 }
200
201#else
202
203 {
204 int word, bit;
205 for (word = vec_max; word--; )
206 {
207 fd_mask word_r = ((fd_mask *)vec_ro) [word];
208 fd_mask word_w = ((fd_mask *)vec_wo) [word];
209
210 if (word_r || word_w)
211 for (bit = NFDBITS; bit--; )
212 {
213 fd_mask mask = 1UL << bit;
214 int events = 0;
215
216 events |= word_r & mask ? EV_READ : 0;
217 events |= word_w & mask ? EV_WRITE : 0;
218
219 if (expect_true (events))
220 fd_event (EV_A_ word * NFDBITS + bit, events);
221 }
222 }
223 }
224
225#endif
226}
227
228int inline_size
125select_init (EV_P_ int flags) 229select_init (EV_P_ int flags)
126{ 230{
127 method_fudge = 1e-2; /* needed to compensate for select returning early, very conservative */ 231 backend_fudge = 0.; /* posix says this is zero */
128 method_modify = select_modify; 232 backend_modify = select_modify;
129 method_poll = select_poll; 233 backend_poll = select_poll;
130 234
235#if EV_SELECT_USE_FD_SET
236 vec_max = FD_SETSIZE / 32;
237 vec_ri = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
238 vec_ro = ev_malloc (sizeof (fd_set));
239 vec_wi = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
240 vec_wo = ev_malloc (sizeof (fd_set));
241#else
242 vec_max = 0;
243 vec_ri = 0;
244 vec_ri = 0;
245 vec_wo = 0;
246 vec_wo = 0;
247#endif
248
131 return EVMETHOD_SELECT; 249 return EVBACKEND_SELECT;
132} 250}
133 251
252void inline_size
253select_destroy (EV_P)
254{
255 ev_free (vec_ri);
256 ev_free (vec_ro);
257 ev_free (vec_wi);
258 ev_free (vec_wo);
259}
260
261

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