1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 1997 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * University Copyright- Copyright (c) 1982, 1986, 1988
32 * The Regents of the University of California
33 * All Rights Reserved
34 *
35 * University Acknowledgment- Portions of this document are derived from
36 * software developed by the University of California, Berkeley, and its
37 * contributors.
38 */
39
40 /*
41 * This function waits for timo clock ticks for something to arrive on
42 * the specified stream. If more than one client is hanging off of a
43 * single endpoint, and at least one has specified a non-zero timeout,
44 * then all will be woken.
45 *
46 * Returns:
47 * 0 on success or positive error code. On
48 * success, "events" is set to
49 * 0 on timeout or no events(timout = 0),
50 * 1 if desired event has occurred
51 *
52 * Most of the code is from strwaitq().
53 */
54
55 #include <sys/param.h>
56 #include <sys/types.h>
57 #include <sys/proc.h>
58 #include <sys/file.h>
59 #include <sys/user.h>
60 #include <sys/vnode.h>
61 #include <sys/errno.h>
62 #include <sys/stream.h>
63 #include <sys/ioctl.h>
64 #include <sys/stropts.h>
65 #include <sys/strsubr.h>
66 #include <sys/tihdr.h>
67 #include <sys/timod.h>
68 #include <sys/tiuser.h>
69 #include <sys/t_kuser.h>
70 #include <sys/signal.h>
71 #include <sys/siginfo.h>
72 #include <sys/time.h>
73 #include <sys/debug.h>
74
75 /*
76 * Poll for an input event.
77 *
78 * timo is measured in ticks
79 */
80 int
t_kspoll(TIUSER * tiptr,int timo,int waitflg,int * events)81 t_kspoll(TIUSER *tiptr, int timo, int waitflg, int *events)
82 {
83 file_t *fp;
84 vnode_t *vp;
85 klwp_t *lwp = ttolwp(curthread);
86 clock_t timout; /* milliseconds */
87 int error;
88 u_char pri;
89 int pflag;
90 rval_t rval;
91
92 fp = tiptr->fp;
93 vp = fp->f_vnode;
94
95 if (events == NULL || ((waitflg & READWAIT) == 0))
96 return (EINVAL);
97
98 /* Convert from ticks to milliseconds */
99 if (timo < 0)
100 timout = -1;
101 else
102 timout = TICK_TO_MSEC(timo);
103
104 /*
105 * Indicate that the lwp is not to be stopped while doing
106 * this network traffic. This is to avoid deadlock while
107 * debugging a process via /proc.
108 */
109 if (lwp != NULL)
110 lwp->lwp_nostop++;
111
112 if (waitflg & NOINTR)
113 pflag = MSG_ANY | MSG_HOLDSIG;
114 else
115 pflag = MSG_ANY;
116 pri = 0;
117 error = kstrgetmsg(vp, NULL, NULL, &pri, &pflag, timout, &rval);
118
119 if (lwp != NULL)
120 lwp->lwp_nostop--;
121
122 /* Set the return *events. */
123 if (error != 0) {
124 if (error == ETIME) {
125 *events = 0;
126 error = 0;
127 }
128 return (error);
129 }
130 *events = 1;
131 return (0);
132 }
133