1 /*
2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Portions copyright (c) 1999, 2000
11 * Intel Corporation.
12 * All rights reserved.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 *
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 *
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 *
25 * 3. All advertising materials mentioning features or use of this software
26 * must display the following acknowledgement:
27 *
28 * This product includes software developed by the University of
29 * California, Berkeley, Intel Corporation, and its contributors.
30 *
31 * 4. Neither the name of University, Intel Corporation, or their respective
32 * contributors may be used to endorse or promote products derived from
33 * this software without specific prior written permission.
34 *
35 * THIS SOFTWARE IS PROVIDED BY THE REGENTS, INTEL CORPORATION AND
36 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
37 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
38 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS,
39 * INTEL CORPORATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
40 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
45 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
46 *
47 * @(#)sys_generic.c 8.5 (Berkeley) 1/21/94
48 * $Id: select.c,v 1.1.1.1 2003/11/19 01:50:30 kyu3 Exp $
49 */
50 #include <Library/UefiBootServicesTableLib.h>
51
52 #include <LibConfig.h>
53
54 #include <stdlib.h>
55 #include <unistd.h>
56 #include <strings.h>
57 #include <sys/poll.h>
58 #include <sys/param.h>
59 #include <sys/time.h>
60 #ifndef KERNEL
61 #define KERNEL
62 #include <errno.h>
63 #undef KERNEL
64 #else
65 #include <errno.h>
66 #endif
67
68 #ifdef EFI_NT_EMULATOR
69 #define _SELECT_DELAY_ 10000
70 #else
71 #define _SELECT_DELAY_ 1000
72 #endif
73
74 #define MAX_SLEEP_DELAY 0xfffffffe
75
76 /** Sleep for the specified number of Microseconds.
77
78 Implements the usleep(3) function.
79
80 @param[in] Microseconds Number of microseconds to sleep.
81
82 @retval 0 Always returns zero.
83 **/
84 int
usleep(useconds_t Microseconds)85 usleep( useconds_t Microseconds )
86 {
87 while ( MAX_SLEEP_DELAY < Microseconds ) {
88 gBS->Stall ( MAX_SLEEP_DELAY );
89 Microseconds -= MAX_SLEEP_DELAY;
90 }
91 gBS->Stall((UINTN)Microseconds );
92 return (0);
93 }
94
95 unsigned int
sleep(unsigned int Seconds)96 sleep( unsigned int Seconds )
97 {
98 return (usleep( (useconds_t)(Seconds * 1000000) ));
99 }
100
101 static int
selscan(fd_mask ** ibits,fd_mask ** obits,int nfd,int * nselected)102 selscan(
103 fd_mask **ibits,
104 fd_mask **obits,
105 int nfd,
106 int *nselected
107 )
108 {
109 int msk;
110 int i;
111 int j;
112 int fd;
113 int n;
114 struct pollfd pfd;
115 int FdCount;
116 fd_mask bits;
117 /* Note: backend also returns POLLHUP/POLLERR if appropriate. */
118 static int16_t flag[3] = { POLLRDNORM, POLLWRNORM, POLLRDBAND };
119
120 for (msk = 0, n = 0; msk < 3; msk++) {
121 if (ibits[msk] == NULL)
122 continue;
123 for (i = 0; i < nfd; i += NFDBITS) {
124 bits = ibits[ msk ][ i / NFDBITS ];
125 while (( 0 != (j = ffs(bits))) && ((fd = i + --j) < nfd)) {
126 bits &= ~(1 << j);
127
128 pfd.fd = fd;
129 pfd.events = flag[msk];
130 pfd.revents = 0;
131 FdCount = poll ( &pfd, 1, 0 );
132 if ( -1 == FdCount ) {
133 return errno;
134 }
135 if ( 0 != FdCount ) {
136 obits[msk][(fd)/NFDBITS] |=
137 (1 << ((fd) % NFDBITS));
138 n++;
139 break;
140 }
141 }
142 }
143 }
144 *nselected = n;
145 return (0);
146 }
147
148 int
select(int nd,fd_set * in,fd_set * ou,fd_set * ex,struct timeval * tv)149 select(
150 int nd,
151 fd_set *in,
152 fd_set *ou,
153 fd_set *ex,
154 struct timeval *tv
155 )
156 {
157 fd_mask *ibits[3], *obits[3], *selbits, *sbp;
158 int error, forever, nselected;
159 u_int nbufbytes, ncpbytes, nfdbits;
160 int64_t timo;
161
162 if (nd < 0)
163 return (EINVAL);
164
165 /*
166 * Allocate just enough bits for the non-null fd_sets. Use the
167 * preallocated auto buffer if possible.
168 */
169 nfdbits = roundup(nd, NFDBITS);
170 ncpbytes = nfdbits / NBBY;
171 nbufbytes = 0;
172 if (in != NULL)
173 nbufbytes += 2 * ncpbytes;
174 if (ou != NULL)
175 nbufbytes += 2 * ncpbytes;
176 if (ex != NULL)
177 nbufbytes += 2 * ncpbytes;
178 selbits = malloc(nbufbytes);
179
180 /*
181 * Assign pointers into the bit buffers and fetch the input bits.
182 * Put the output buffers together so that they can be bzeroed
183 * together.
184 */
185 sbp = selbits;
186 #define getbits(name, x) \
187 do { \
188 if (name == NULL) \
189 ibits[x] = NULL; \
190 else { \
191 ibits[x] = sbp + nbufbytes / 2 / sizeof *sbp; \
192 obits[x] = sbp; \
193 sbp += ncpbytes / sizeof *sbp; \
194 bcopy(name, ibits[x], ncpbytes); \
195 } \
196 } while (0)
197 getbits(in, 0);
198 getbits(ou, 1);
199 getbits(ex, 2);
200 #undef getbits
201 if (nbufbytes != 0)
202 memset(selbits, 0, nbufbytes / 2);
203
204 if (tv) {
205 timo = tv->tv_usec + (tv->tv_sec * 1000000);
206 forever = 0;
207 } else {
208 timo = 0;
209 forever = 1;
210 }
211
212 /*
213 * Poll for I/O events
214 */
215 nselected = 0;
216 do {
217 /*
218 * Scan for pending I/O
219 */
220 error = selscan(ibits, obits, nd, &nselected);
221 if (error || nselected)
222 break;
223
224 /*
225 * Adjust timeout is needed
226 */
227 if (timo) {
228 /*
229 * Give it a rest
230 */
231 usleep( _SELECT_DELAY_ );
232 timo -= _SELECT_DELAY_;
233 }
234
235 } while (timo > 0 || forever);
236
237 /* select is not restarted after signals... */
238 if (error == ERESTART)
239 error = EINTR;
240 else if (error == EWOULDBLOCK)
241 error = 0;
242
243 #define putbits(name, x) if (name) bcopy(obits[x], name, ncpbytes)
244 if (error == 0) {
245 putbits(in, 0);
246 putbits(ou, 1);
247 putbits(ex, 2);
248 #undef putbits
249 } else {
250 errno = error;
251 nselected = -1;
252 }
253
254 free( selbits );
255 return ( nselected );
256 }
257