1 /*
2 * Copyright (c) 2005, 2007 Apple Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24 #if defined(__LP64__) && (defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050))
25 #undef __DARWIN_NON_CANCELABLE
26 #define __DARWIN_NON_CANCELABLE 0
27 #endif /* __LP64__ && (VARIANT_CANCELABLE || VARIANT_PRE1050) */
28
29 #if defined(VARIANT_DARWIN_EXTSN)
30 #define _DARWIN_C_SOURCE
31 #define _DARWIN_UNLIMITED_SELECT
32 #endif
33
34 #include <sys/select.h>
35 #include <sys/time.h>
36 #include <sys/signal.h>
37 #include "_errno.h"
38
39 #if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
40 #if !defined(VARIANT_DARWIN_EXTSN)
41 extern int __select(int, fd_set * __restrict, fd_set * __restrict,
42 fd_set * __restrict, struct timeval * __restrict);
43 #endif
44 int __pselect(int, fd_set * __restrict, fd_set * __restrict,
45 fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
46 #else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
47 #if !defined(VARIANT_DARWIN_EXTSN)
48 int __select_nocancel(int, fd_set * __restrict, fd_set * __restrict,
49 fd_set * __restrict, struct timeval * __restrict);
50 #endif
51 int __pselect_nocancel(int, fd_set * __restrict, fd_set * __restrict,
52 fd_set * __restrict, const struct timespec * __restrict, const sigset_t * __restrict);
53 #endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */
54
55 #if !defined(VARIANT_DARWIN_EXTSN)
56 /*
57 * select() implementation for 1050 and legacy (cancelable and non-cancelable)
58 * variants. The darwin extension variants (both cancelable & non-cancelable) are
59 * mapped directly to the syscall stub.
60 */
61 int
select(int nfds,fd_set * __restrict readfds,fd_set * __restrict writefds,fd_set * __restrict exceptfds,struct timeval * __restrict intimeout)62 select(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
63 fd_set * __restrict exceptfds, struct timeval * __restrict
64 #if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
65 intimeout
66 #else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
67 timeout
68 #endif /* VARIANT_LEGACY || VARIANT_PRE1050 */
69 )
70 {
71 #if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
72 struct timeval tb, *timeout;
73
74 /*
75 * Legacy select behavior is minimum 10 msec when tv_usec is non-zero
76 */
77 if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_usec > 0 && intimeout->tv_usec < 10000) {
78 tb.tv_sec = 0;
79 tb.tv_usec = 10000;
80 timeout = &tb;
81 } else {
82 timeout = intimeout;
83 }
84 #else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
85 if (nfds > FD_SETSIZE) {
86 errno = EINVAL;
87 return -1;
88 }
89 #endif
90
91 #if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
92 return __select(nfds, readfds, writefds, exceptfds, timeout);
93 #else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
94 return __select_nocancel(nfds, readfds, writefds, exceptfds, timeout);
95 #endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */
96 }
97 #endif /* !defined(VARIANT_DARWIN_EXTSN) */
98
99
100 /*
101 * User-space emulation of pselect() syscall for B&I
102 * TODO: remove when B&I move to xnu with native pselect()
103 */
104 extern int __pthread_sigmask(int, const sigset_t *, sigset_t *);
105 static int
_pselect_emulated(int count,fd_set * __restrict rfds,fd_set * __restrict wfds,fd_set * __restrict efds,const struct timespec * __restrict timo,const sigset_t * __restrict mask)106 _pselect_emulated(int count, fd_set * __restrict rfds, fd_set * __restrict wfds,
107 fd_set * __restrict efds, const struct timespec * __restrict timo,
108 const sigset_t * __restrict mask)
109 {
110 sigset_t omask;
111 struct timeval tvtimo, *tvp;
112 int rv, sverrno;
113
114 if (timo) {
115 tvtimo.tv_sec = timo->tv_sec;
116 tvtimo.tv_usec = (__darwin_suseconds_t)(timo->tv_nsec / 1000);
117 tvp = &tvtimo;
118 } else {
119 tvp = 0;
120 }
121
122 if (mask != 0) {
123 rv = __pthread_sigmask(SIG_SETMASK, mask, &omask);
124 if (rv != 0) {
125 return rv;
126 }
127 }
128
129 rv = select(count, rfds, wfds, efds, tvp);
130 if (mask != 0) {
131 sverrno = errno;
132 __pthread_sigmask(SIG_SETMASK, &omask, (sigset_t *)0);
133 errno = sverrno;
134 }
135
136 return rv;
137 }
138
139 /*
140 * pselect() implementation for all variants. Unlike select(), we implement the
141 * darwin extension variants here to catch cases where xnu doesn't implement
142 * pselect and we need to emulate.
143 */
144 int
pselect(int nfds,fd_set * __restrict readfds,fd_set * __restrict writefds,fd_set * __restrict exceptfds,const struct timespec * __restrict intimeout,const sigset_t * __restrict sigmask)145 pselect(int nfds, fd_set * __restrict readfds, fd_set * __restrict writefds,
146 fd_set * __restrict exceptfds, const struct timespec * __restrict
147 #if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
148 intimeout,
149 #else /* !VARIANT_LEGACY && !VARIANT_PRE1050 */
150 timeout,
151 #endif /* VARIANT_LEGACY || VARIANT_PRE1050 */
152 const sigset_t * __restrict sigmask)
153 {
154 int ret;
155 #if defined(VARIANT_LEGACY) || defined(VARIANT_PRE1050)
156 struct timespec tb;
157 const struct timespec *timeout;
158
159 /*
160 * Legacy select behavior is minimum 10 msec when tv_usec is non-zero
161 */
162 if (intimeout && intimeout->tv_sec == 0 && intimeout->tv_nsec > 0 && intimeout->tv_nsec < 10000000L) {
163 tb.tv_sec = 0;
164 tb.tv_nsec = 10000000L;
165 timeout = &tb;
166 } else {
167 timeout = intimeout;
168 }
169 #elif defined(VARIANT_DARWIN_EXTSN)
170 #else
171 /* 1050 variant */
172 if (nfds > FD_SETSIZE) {
173 errno = EINVAL;
174 return -1;
175 }
176 #endif
177
178 #if defined(VARIANT_CANCELABLE) || defined(VARIANT_PRE1050)
179 ret = __pselect(nfds, readfds, writefds, exceptfds, timeout, sigmask);
180 #else /* !VARIANT_CANCELABLE && !VARIANT_PRE1050 */
181 ret = __pselect_nocancel(nfds, readfds, writefds, exceptfds, timeout, sigmask);
182 #endif /* VARIANT_CANCELABLE || VARIANT_PRE1050 */
183
184 if (ret == -1 && errno == ENOSYS) {
185 ret = _pselect_emulated(nfds, readfds, writefds, exceptfds, timeout, sigmask);
186 }
187
188 return ret;
189 }
190