signalvar.h revision 315949 
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 * 4. 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: stable/10/sys/sys/signalvar.h 315949 2017-03-25 13:33:23Z badger $
31 */
32
33#ifndef _SYS_SIGNALVAR_H_
34#define	_SYS_SIGNALVAR_H_
35
36#include <sys/queue.h>
37#include <sys/_lock.h>
38#include <sys/_mutex.h>
39#include <sys/signal.h>
40
41/*
42 * Kernel signal definitions and data structures.
43 */
44
45/*
46 * Logical process signal actions and state, needed only within the process
47 * The mapping between sigacts and proc structures is 1:1 except for rfork()
48 * processes masquerading as threads which use one structure for the whole
49 * group.  All members are locked by the included mutex.  The reference count
50 * and mutex must be last for the bcopy in sigacts_copy() to work.
51 */
52struct sigacts {
53	sig_t	ps_sigact[_SIG_MAXSIG];	/* Disposition of signals. */
54	sigset_t ps_catchmask[_SIG_MAXSIG];	/* Signals to be blocked. */
55	sigset_t ps_sigonstack;		/* Signals to take on sigstack. */
56	sigset_t ps_sigintr;		/* Signals that interrupt syscalls. */
57	sigset_t ps_sigreset;		/* Signals that reset when caught. */
58	sigset_t ps_signodefer;		/* Signals not masked while handled. */
59	sigset_t ps_siginfo;		/* Signals that want SA_SIGINFO args. */
60	sigset_t ps_sigignore;		/* Signals being ignored. */
61	sigset_t ps_sigcatch;		/* Signals being caught by user. */
62	sigset_t ps_freebsd4;		/* Signals using freebsd4 ucontext. */
63	sigset_t ps_osigset;		/* Signals using <= 3.x osigset_t. */
64	sigset_t ps_usertramp;		/* SunOS compat; libc sigtramp. XXX */
65	int	ps_flag;
66	u_int	ps_refcnt;
67	struct mtx ps_mtx;
68};
69
70#define	PS_NOCLDWAIT	0x0001	/* No zombies if child dies */
71#define	PS_NOCLDSTOP	0x0002	/* No SIGCHLD when children stop. */
72#define	PS_CLDSIGIGN	0x0004	/* The SIGCHLD handler is SIG_IGN. */
73
74#ifdef _KERNEL
75
76#ifdef COMPAT_43
77typedef struct {
78	struct osigcontext si_sc;
79	int		si_signo;
80	int		si_code;
81	union sigval	si_value;
82} osiginfo_t;
83
84struct osigaction {
85	union {
86		void    (*__sa_handler)(int);
87		void    (*__sa_sigaction)(int, osiginfo_t *, void *);
88	} __sigaction_u;		/* signal handler */
89	osigset_t	sa_mask;	/* signal mask to apply */
90	int		sa_flags;	/* see signal options below */
91};
92
93typedef void __osiginfohandler_t(int, osiginfo_t *, void *);
94#endif /* COMPAT_43 */
95
96/* additional signal action values, used only temporarily/internally */
97#define	SIG_CATCH	((__sighandler_t *)2)
98/* #define SIG_HOLD        ((__sighandler_t *)3) See signal.h */
99
100/*
101 * get signal action for process and signal; currently only for current process
102 */
103#define	SIGACTION(p, sig)	(p->p_sigacts->ps_sigact[_SIG_IDX(sig)])
104
105#endif /* _KERNEL */
106
107/*
108 * sigset_t manipulation macros.
109 */
110#define	SIGADDSET(set, signo)						\
111	((set).__bits[_SIG_WORD(signo)] |= _SIG_BIT(signo))
112
113#define	SIGDELSET(set, signo)						\
114	((set).__bits[_SIG_WORD(signo)] &= ~_SIG_BIT(signo))
115
116#define	SIGEMPTYSET(set)						\
117	do {								\
118		int __i;						\
119		for (__i = 0; __i < _SIG_WORDS; __i++)			\
120			(set).__bits[__i] = 0;				\
121	} while (0)
122
123#define	SIGFILLSET(set)							\
124	do {								\
125		int __i;						\
126		for (__i = 0; __i < _SIG_WORDS; __i++)			\
127			(set).__bits[__i] = ~0U;			\
128	} while (0)
129
130#define	SIGISMEMBER(set, signo)						\
131	((set).__bits[_SIG_WORD(signo)] & _SIG_BIT(signo))
132
133#define	SIGISEMPTY(set)		(__sigisempty(&(set)))
134#define	SIGNOTEMPTY(set)	(!__sigisempty(&(set)))
135
136#define	SIGSETEQ(set1, set2)	(__sigseteq(&(set1), &(set2)))
137#define	SIGSETNEQ(set1, set2)	(!__sigseteq(&(set1), &(set2)))
138
139#define	SIGSETOR(set1, set2)						\
140	do {								\
141		int __i;						\
142		for (__i = 0; __i < _SIG_WORDS; __i++)			\
143			(set1).__bits[__i] |= (set2).__bits[__i];	\
144	} while (0)
145
146#define	SIGSETAND(set1, set2)						\
147	do {								\
148		int __i;						\
149		for (__i = 0; __i < _SIG_WORDS; __i++)			\
150			(set1).__bits[__i] &= (set2).__bits[__i];	\
151	} while (0)
152
153#define	SIGSETNAND(set1, set2)						\
154	do {								\
155		int __i;						\
156		for (__i = 0; __i < _SIG_WORDS; __i++)			\
157			(set1).__bits[__i] &= ~(set2).__bits[__i];	\
158	} while (0)
159
160#define	SIGSETLO(set1, set2)	((set1).__bits[0] = (set2).__bits[0])
161#define	SIGSETOLD(set, oset)	((set).__bits[0] = (oset))
162
163#define	SIG_CANTMASK(set)						\
164	SIGDELSET(set, SIGKILL), SIGDELSET(set, SIGSTOP)
165
166#define	SIG_STOPSIGMASK(set)						\
167	SIGDELSET(set, SIGSTOP), SIGDELSET(set, SIGTSTP),		\
168	SIGDELSET(set, SIGTTIN), SIGDELSET(set, SIGTTOU)
169
170#define	SIG_CONTSIGMASK(set)						\
171	SIGDELSET(set, SIGCONT)
172
173#define	sigcantmask	(sigmask(SIGKILL) | sigmask(SIGSTOP))
174
175#define	SIG2OSIG(sig, osig)	(osig = (sig).__bits[0])
176#define	OSIG2SIG(osig, sig)	SIGEMPTYSET(sig); (sig).__bits[0] = osig
177
178static __inline int
179__sigisempty(sigset_t *set)
180{
181	int i;
182
183	for (i = 0; i < _SIG_WORDS; i++) {
184		if (set->__bits[i])
185			return (0);
186	}
187	return (1);
188}
189
190static __inline int
191__sigseteq(sigset_t *set1, sigset_t *set2)
192{
193	int i;
194
195	for (i = 0; i < _SIG_WORDS; i++) {
196		if (set1->__bits[i] != set2->__bits[i])
197			return (0);
198	}
199	return (1);
200}
201
202struct osigevent {
203	int	sigev_notify;		/* Notification type */
204	union {
205		int	__sigev_signo;	/* Signal number */
206		int	__sigev_notify_kqueue;
207	} __sigev_u;
208	union sigval sigev_value;	/* Signal value */
209};
210
211typedef struct ksiginfo {
212	TAILQ_ENTRY(ksiginfo)	ksi_link;
213	siginfo_t		ksi_info;
214	int			ksi_flags;
215	struct sigqueue		*ksi_sigq;
216} ksiginfo_t;
217
218#define	ksi_signo	ksi_info.si_signo
219#define	ksi_errno	ksi_info.si_errno
220#define	ksi_code	ksi_info.si_code
221#define	ksi_pid		ksi_info.si_pid
222#define	ksi_uid		ksi_info.si_uid
223#define	ksi_status      ksi_info.si_status
224#define	ksi_addr        ksi_info.si_addr
225#define	ksi_value	ksi_info.si_value
226#define	ksi_band	ksi_info.si_band
227#define	ksi_trapno	ksi_info.si_trapno
228#define	ksi_overrun	ksi_info.si_overrun
229#define	ksi_timerid	ksi_info.si_timerid
230#define	ksi_mqd		ksi_info.si_mqd
231
232/* bits for ksi_flags */
233#define	KSI_TRAP	0x01	/* Generated by trap. */
234#define	KSI_EXT		0x02	/* Externally managed ksi. */
235#define	KSI_INS		0x04	/* Directly insert ksi, not the copy */
236#define	KSI_SIGQ	0x08	/* Generated by sigqueue, might ret EAGAIN. */
237#define	KSI_HEAD	0x10	/* Insert into head, not tail. */
238#define	KSI_PTRACE	0x20	/* Generated by ptrace. */
239#define	KSI_COPYMASK	(KSI_TRAP | KSI_SIGQ | KSI_PTRACE)
240
241#define	KSI_ONQ(ksi)	((ksi)->ksi_sigq != NULL)
242
243typedef struct sigqueue {
244	sigset_t	sq_signals;	/* All pending signals. */
245	sigset_t	sq_kill;	/* Legacy depth 1 queue. */
246	sigset_t	sq_ptrace;	/* Depth 1 queue for ptrace(2). */
247	TAILQ_HEAD(, ksiginfo)	sq_list;/* Queued signal info. */
248	struct proc	*sq_proc;
249	int		sq_flags;
250} sigqueue_t;
251
252/* Flags for ksi_flags */
253#define	SQ_INIT	0x01
254
255#ifdef _KERNEL
256
257/* Return nonzero if process p has an unmasked pending signal. */
258#define	SIGPENDING(td)							\
259	((!SIGISEMPTY((td)->td_siglist) &&				\
260	    !sigsetmasked(&(td)->td_siglist, &(td)->td_sigmask)) ||	\
261	 (!SIGISEMPTY((td)->td_proc->p_siglist) &&			\
262	    !sigsetmasked(&(td)->td_proc->p_siglist, &(td)->td_sigmask)))
263/*
264 * Return the value of the pseudo-expression ((*set & ~*mask) != 0).  This
265 * is an optimized version of SIGISEMPTY() on a temporary variable
266 * containing SIGSETNAND(*set, *mask).
267 */
268static __inline int
269sigsetmasked(sigset_t *set, sigset_t *mask)
270{
271	int i;
272
273	for (i = 0; i < _SIG_WORDS; i++) {
274		if (set->__bits[i] & ~mask->__bits[i])
275			return (0);
276	}
277	return (1);
278}
279
280#define	ksiginfo_init(ksi)			\
281do {						\
282	bzero(ksi, sizeof(ksiginfo_t));		\
283} while(0)
284
285#define	ksiginfo_init_trap(ksi)			\
286do {						\
287	ksiginfo_t *kp = ksi;			\
288	bzero(kp, sizeof(ksiginfo_t));		\
289	kp->ksi_flags |= KSI_TRAP;		\
290} while(0)
291
292static __inline void
293ksiginfo_copy(ksiginfo_t *src, ksiginfo_t *dst)
294{
295	(dst)->ksi_info = src->ksi_info;
296	(dst)->ksi_flags = (src->ksi_flags & KSI_COPYMASK);
297}
298
299static __inline void
300ksiginfo_set_sigev(ksiginfo_t *dst, struct sigevent *sigev)
301{
302	dst->ksi_signo = sigev->sigev_signo;
303	dst->ksi_value = sigev->sigev_value;
304}
305
306struct pgrp;
307struct proc;
308struct sigio;
309struct thread;
310
311/*
312 * Lock the pointers for a sigio object in the underlying objects of
313 * a file descriptor.
314 */
315#define	SIGIO_LOCK()	mtx_lock(&sigio_lock)
316#define	SIGIO_TRYLOCK()	mtx_trylock(&sigio_lock)
317#define	SIGIO_UNLOCK()	mtx_unlock(&sigio_lock)
318#define	SIGIO_LOCKED()	mtx_owned(&sigio_lock)
319#define	SIGIO_ASSERT(type)	mtx_assert(&sigio_lock, type)
320
321extern struct mtx	sigio_lock;
322
323/* Flags for kern_sigprocmask(). */
324#define	SIGPROCMASK_OLD		0x0001
325#define	SIGPROCMASK_PROC_LOCKED	0x0002
326#define	SIGPROCMASK_PS_LOCKED	0x0004
327
328int	cursig(struct thread *td);
329int	sigdeferstop(void);
330int	sigallowstop(void);
331void	execsigs(struct proc *p);
332void	gsignal(int pgid, int sig, ksiginfo_t *ksi);
333void	killproc(struct proc *p, char *why);
334ksiginfo_t * ksiginfo_alloc(int wait);
335void	ksiginfo_free(ksiginfo_t *ksi);
336int	pksignal(struct proc *p, int sig, ksiginfo_t *ksi);
337void	pgsigio(struct sigio **sigiop, int sig, int checkctty);
338void	pgsignal(struct pgrp *pgrp, int sig, int checkctty, ksiginfo_t *ksi);
339int	postsig(int sig);
340void	kern_psignal(struct proc *p, int sig);
341int	ptracestop(struct thread *td, int sig, ksiginfo_t *si);
342void	sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *retmask);
343struct sigacts *sigacts_alloc(void);
344void	sigacts_copy(struct sigacts *dest, struct sigacts *src);
345void	sigacts_free(struct sigacts *ps);
346struct sigacts *sigacts_hold(struct sigacts *ps);
347int	sigacts_shared(struct sigacts *ps);
348void	sigexit(struct thread *td, int sig) __dead2;
349int	sigev_findtd(struct proc *p, struct sigevent *sigev, struct thread **);
350int	sig_ffs(sigset_t *set);
351void	siginit(struct proc *p);
352void	signotify(struct thread *td);
353void	sigqueue_delete(struct sigqueue *queue, int sig);
354void	sigqueue_delete_proc(struct proc *p, int sig);
355void	sigqueue_flush(struct sigqueue *queue);
356void	sigqueue_init(struct sigqueue *queue, struct proc *p);
357void	sigqueue_take(ksiginfo_t *ksi);
358void	tdksignal(struct thread *td, int sig, ksiginfo_t *ksi);
359int	tdsendsignal(struct proc *p, struct thread *td, int sig,
360	   ksiginfo_t *ksi);
361void	tdsigcleanup(struct thread *td);
362void	tdsignal(struct thread *td, int sig);
363void	trapsignal(struct thread *td, ksiginfo_t *ksi);
364
365#endif /* _KERNEL */
366
367#endif /* !_SYS_SIGNALVAR_H_ */
368