signalvar.h revision 195702 
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: head/sys/sys/signalvar.h 195702 2009-07-14 22:52:46Z kib $
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 * not exported to user programs.
44 */
45
46/*
47 * Logical process signal actions and state, needed only within the process
48 * The mapping between sigacts and proc structures is 1:1 except for rfork()
49 * processes masquerading as threads which use one structure for the whole
50 * group.  All members are locked by the included mutex.  The reference count
51 * and mutex must be last for the bcopy in sigacts_copy() to work.
52 */
53struct sigacts {
54	sig_t	ps_sigact[_SIG_MAXSIG];	/* Disposition of signals. */
55	sigset_t ps_catchmask[_SIG_MAXSIG];	/* Signals to be blocked. */
56	sigset_t ps_sigonstack;		/* Signals to take on sigstack. */
57	sigset_t ps_sigintr;		/* Signals that interrupt syscalls. */
58	sigset_t ps_sigreset;		/* Signals that reset when caught. */
59	sigset_t ps_signodefer;		/* Signals not masked while handled. */
60	sigset_t ps_siginfo;		/* Signals that want SA_SIGINFO args. */
61	sigset_t ps_sigignore;		/* Signals being ignored. */
62	sigset_t ps_sigcatch;		/* Signals being caught by user. */
63	sigset_t ps_freebsd4;		/* signals using freebsd4 ucontext. */
64	sigset_t ps_osigset;		/* Signals using <= 3.x osigset_t. */
65	sigset_t ps_usertramp;		/* SunOS compat; libc sigtramp. XXX */
66	int	ps_flag;
67	int	ps_refcnt;
68	struct mtx ps_mtx;
69};
70
71#define	PS_NOCLDWAIT	0x0001	/* No zombies if child dies */
72#define	PS_NOCLDSTOP	0x0002	/* No SIGCHLD when children stop. */
73#define	PS_CLDSIGIGN	0x0004	/* The SIGCHLD handler is SIG_IGN. */
74
75#if defined(_KERNEL) && defined(COMPAT_43)
76/*
77 * Compatibility.
78 */
79typedef struct {
80	struct osigcontext si_sc;
81	int		si_signo;
82	int		si_code;
83	union sigval	si_value;
84} osiginfo_t;
85
86struct osigaction {
87	union {
88		void    (*__sa_handler)(int);
89		void    (*__sa_sigaction)(int, osiginfo_t *, void *);
90	} __sigaction_u;		/* signal handler */
91	osigset_t	sa_mask;	/* signal mask to apply */
92	int		sa_flags;	/* see signal options below */
93};
94
95typedef void __osiginfohandler_t(int, osiginfo_t *, void *);
96#endif /* _KERNEL && COMPAT_43 */
97
98/* additional signal action values, used only temporarily/internally */
99#define	SIG_CATCH	((__sighandler_t *)2)
100#define SIG_HOLD        ((__sighandler_t *)3)
101
102/*
103 * get signal action for process and signal; currently only for current process
104 */
105#define SIGACTION(p, sig)	(p->p_sigacts->ps_sigact[_SIG_IDX(sig)])
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_COPYMASK	KSI_TRAP
237
238#define	KSI_ONQ(ksi)	((ksi)->ksi_sigq != NULL)
239
240typedef struct sigqueue {
241	sigset_t	sq_signals;	/* All pending signals. */
242	sigset_t	sq_kill;	/* Legacy depth 1 queue. */
243	TAILQ_HEAD(, ksiginfo)	sq_list;/* Queued signal info. */
244	struct proc	*sq_proc;
245	int		sq_flags;
246} sigqueue_t;
247
248/* Flags for ksi_flags */
249#define	SQ_INIT	0x01
250
251#ifdef _KERNEL
252
253/* Return nonzero if process p has an unmasked pending signal. */
254#define	SIGPENDING(td)							\
255	(!SIGISEMPTY((td)->td_siglist) &&				\
256	    !sigsetmasked(&(td)->td_siglist, &(td)->td_sigmask))
257
258/*
259 * Return the value of the pseudo-expression ((*set & ~*mask) != 0).  This
260 * is an optimized version of SIGISEMPTY() on a temporary variable
261 * containing SIGSETNAND(*set, *mask).
262 */
263static __inline int
264sigsetmasked(sigset_t *set, sigset_t *mask)
265{
266	int i;
267
268	for (i = 0; i < _SIG_WORDS; i++) {
269		if (set->__bits[i] & ~mask->__bits[i])
270			return (0);
271	}
272	return (1);
273}
274
275#define ksiginfo_init(ksi)			\
276do {						\
277	bzero(ksi, sizeof(ksiginfo_t));		\
278} while(0)
279
280#define ksiginfo_init_trap(ksi)			\
281do {						\
282	ksiginfo_t *kp = ksi;			\
283	bzero(kp, sizeof(ksiginfo_t));		\
284	kp->ksi_flags |= KSI_TRAP;		\
285} while(0)
286
287static __inline void
288ksiginfo_copy(ksiginfo_t *src, ksiginfo_t *dst)
289{
290	(dst)->ksi_info = src->ksi_info;
291	(dst)->ksi_flags = (src->ksi_flags & KSI_COPYMASK);
292}
293
294struct pgrp;
295struct thread;
296struct proc;
297struct sigio;
298struct mtx;
299
300extern int sugid_coredump;	/* Sysctl variable kern.sugid_coredump */
301extern struct mtx	sigio_lock;
302extern int kern_logsigexit;	/* Sysctl variable kern.logsigexit */
303
304/*
305 * Lock the pointers for a sigio object in the underlying objects of
306 * a file descriptor.
307 */
308#define SIGIO_LOCK()	mtx_lock(&sigio_lock)
309#define SIGIO_TRYLOCK()	mtx_trylock(&sigio_lock)
310#define SIGIO_UNLOCK()	mtx_unlock(&sigio_lock)
311#define SIGIO_LOCKED()	mtx_owned(&sigio_lock)
312#define SIGIO_ASSERT(type)	mtx_assert(&sigio_lock, type)
313
314/* stop_allowed parameter for cursig */
315#define	SIG_STOP_ALLOWED	100
316#define	SIG_STOP_NOT_ALLOWED	101
317
318/*
319 * Machine-independent functions:
320 */
321int	cursig(struct thread *td, int stop_allowed);
322void	execsigs(struct proc *p);
323void	gsignal(int pgid, int sig);
324void	killproc(struct proc *p, char *why);
325void	pgsigio(struct sigio **, int signum, int checkctty);
326void	pgsignal(struct pgrp *pgrp, int sig, int checkctty);
327void	postsig(int sig);
328void	psignal(struct proc *p, int sig);
329int	psignal_event(struct proc *p, struct sigevent *, ksiginfo_t *);
330struct sigacts *sigacts_alloc(void);
331void	sigacts_copy(struct sigacts *dest, struct sigacts *src);
332void	sigacts_free(struct sigacts *ps);
333struct sigacts *sigacts_hold(struct sigacts *ps);
334int	sigacts_shared(struct sigacts *ps);
335void	sigexit(struct thread *td, int signum) __dead2;
336int	sig_ffs(sigset_t *set);
337void	siginit(struct proc *p);
338void	signotify(struct thread *td);
339int	tdsignal(struct proc *p, struct thread *td, int sig,
340	    ksiginfo_t *ksi);
341void	trapsignal(struct thread *td, ksiginfo_t *);
342int	ptracestop(struct thread *td, int sig);
343ksiginfo_t * ksiginfo_alloc(int);
344void	ksiginfo_free(ksiginfo_t *);
345void	sigqueue_init(struct sigqueue *queue, struct proc *p);
346void	sigqueue_flush(struct sigqueue *queue);
347void	sigqueue_delete_proc(struct proc *p, int sig);
348void	sigqueue_delete_set(struct sigqueue *queue, sigset_t *set);
349void	sigqueue_delete(struct sigqueue *queue, int sig);
350void	sigqueue_move_set(struct sigqueue *src, sigqueue_t *dst, sigset_t *);
351int	sigqueue_get(struct sigqueue *queue, int sig, ksiginfo_t *info);
352int	sigqueue_add(struct sigqueue *queue, int sig, ksiginfo_t *info);
353void	sigqueue_collect_set(struct sigqueue *queue, sigset_t *set);
354void	sigqueue_move(struct sigqueue *, struct sigqueue *, int sig);
355void	sigqueue_delete_set_proc(struct proc *, sigset_t *);
356void	sigqueue_delete_stopmask_proc(struct proc *);
357void	sigqueue_take(ksiginfo_t *ksi);
358int	kern_sigtimedwait(struct thread *, sigset_t,
359		ksiginfo_t *, struct timespec *);
360
361/*
362 * Machine-dependent functions:
363 */
364void	sendsig(sig_t, ksiginfo_t *, sigset_t *retmask);
365
366#endif /* _KERNEL */
367
368#endif /* !_SYS_SIGNALVAR_H_ */
369