xref: /dragonfly/sys/sys/signal2.h (revision 6ab64ab6)
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)signalvar.h	8.6 (Berkeley) 2/19/95
30  * $FreeBSD: src/sys/sys/signalvar.h,v 1.34.2.1 2000/05/16 06:58:05 dillon Exp $
31  * $DragonFly: src/sys/sys/signal2.h,v 1.3 2008/10/14 21:25:14 swildner Exp $
32  */
33 
34 #ifndef _SYS_SIGNAL2_H
35 #define _SYS_SIGNAL2_H
36 
37 #include <sys/proc.h>
38 
39 /*
40  * Inline functions:
41  */
42 /*
43  * Determine which signals are pending for a lwp.
44  *
45  * (Does not need to be interlocked with lwp_spin.  If caller holds a
46  *  critical section races will be resolved through an AST).
47  */
48 static __inline sigset_t
49 lwp_sigpend(struct lwp *lp)
50 {
51 	sigset_t set;
52 
53 	set = lp->lwp_proc->p_siglist;
54 	SIGSETOR(set, lp->lwp_siglist);
55 	return (set);
56 }
57 
58 /*
59  * Mark a signal as handled by the lwp.
60  *
61  * (p->p_token must be held, lp->lwp_spin must be held)
62  */
63 static __inline void
64 lwp_delsig(struct lwp *lp, int sig)
65 {
66 	SIGDELSET(lp->lwp_siglist, sig);
67 	SIGDELSET(lp->lwp_proc->p_siglist, sig);
68 }
69 
70 #define	CURSIG(lp)		__cursig(lp, 1, 0)
71 #define	CURSIG_TRACE(lp)	__cursig(lp, 1, 1)
72 #define CURSIG_NOBLOCK(lp)	__cursig(lp, 0, 0)
73 
74 /*
75  * Determine signal that should be delivered to process p, the current
76  * process, 0 if none.  If there is a pending stop signal with default
77  * action, the process stops in issignal().
78  *
79  * This function does not interlock pending signals.  If the caller needs
80  * to interlock the caller must acquire the per-proc token.
81  *
82  * MPSAFE
83  */
84 static __inline
85 int
86 __cursig(struct lwp *lp, int mayblock, int maytrace)
87 {
88 	struct proc *p = lp->lwp_proc;
89 	sigset_t tmpset;
90 	int r;
91 
92 	tmpset = lwp_sigpend(lp);
93 	SIGSETNAND(tmpset, lp->lwp_sigmask);
94 
95 	/* Nothing interesting happening? */
96 	if (SIGISEMPTY(tmpset)) {
97 		/*
98 		 * Quit here, unless
99 		 *  a) we may block and
100 		 *  b) somebody is tracing us.
101 		 */
102 		if (!(mayblock && (p->p_flags & P_TRACED)))
103 			return (0);
104 	}
105 
106 	if (mayblock)
107 		r = issignal(lp, maytrace);
108 	else
109 		r = TRUE;	/* simply state the fact */
110 
111 	return(r);
112 }
113 
114 #endif
115