xref: /dragonfly/sys/sys/signal2.h (revision d4ef6694)
1 /*
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)signalvar.h	8.6 (Berkeley) 2/19/95
34  * $FreeBSD: src/sys/sys/signalvar.h,v 1.34.2.1 2000/05/16 06:58:05 dillon Exp $
35  * $DragonFly: src/sys/sys/signal2.h,v 1.3 2008/10/14 21:25:14 swildner Exp $
36  */
37 
38 #ifndef _SYS_SIGNAL2_H
39 #define _SYS_SIGNAL2_H
40 
41 #include <sys/proc.h>
42 
43 /*
44  * Inline functions:
45  */
46 /*
47  * Determine which signals are pending for a lwp.
48  *
49  * (Does not need to be interlocked with lwp_spin.  If caller holds a
50  *  critical section races will be resolved through an AST).
51  */
52 static __inline sigset_t
53 lwp_sigpend(struct lwp *lp)
54 {
55 	sigset_t set;
56 
57 	set = lp->lwp_proc->p_siglist;
58 	SIGSETOR(set, lp->lwp_siglist);
59 	return (set);
60 }
61 
62 /*
63  * Mark a signal as handled by the lwp.
64  *
65  * (p->p_token must be held, lp->lwp_spin must be held)
66  */
67 static __inline void
68 lwp_delsig(struct lwp *lp, int sig)
69 {
70 	SIGDELSET(lp->lwp_siglist, sig);
71 	SIGDELSET(lp->lwp_proc->p_siglist, sig);
72 }
73 
74 #define	CURSIG(lp)		__cursig(lp, 1, 0)
75 #define	CURSIG_TRACE(lp)	__cursig(lp, 1, 1)
76 #define CURSIG_NOBLOCK(lp)	__cursig(lp, 0, 0)
77 
78 /*
79  * Determine signal that should be delivered to process p, the current
80  * process, 0 if none.  If there is a pending stop signal with default
81  * action, the process stops in issignal().
82  *
83  * This function does not interlock pending signals.  If the caller needs
84  * to interlock the caller must acquire the per-proc token.
85  *
86  * MPSAFE
87  */
88 static __inline
89 int
90 __cursig(struct lwp *lp, int mayblock, int maytrace)
91 {
92 	struct proc *p = lp->lwp_proc;
93 	sigset_t tmpset;
94 	int r;
95 
96 	tmpset = lwp_sigpend(lp);
97 	SIGSETNAND(tmpset, lp->lwp_sigmask);
98 
99 	/* Nothing interesting happening? */
100 	if (SIGISEMPTY(tmpset)) {
101 		/*
102 		 * Quit here, unless
103 		 *  a) we may block and
104 		 *  b) somebody is tracing us.
105 		 */
106 		if (!(mayblock && (p->p_flags & P_TRACED)))
107 			return (0);
108 	}
109 
110 	if (mayblock)
111 		r = issignal(lp, maytrace);
112 	else
113 		r = TRUE;	/* simply state the fact */
114 
115 	return(r);
116 }
117 
118 #endif
119