linux/include/linux/signal.h

#ifndef _LINUX_SIGNAL_H
#define _LINUX_SIGNAL_H

#include <asm/signal.h>
#include <asm/siginfo.h>

#ifdef __KERNEL__
#include <linux/list.h>
#include <linux/spinlock.h>

/*
 * Real Time signals may be queued.
 */

struct sigqueue {
	struct list_head list;
	int flags;
	siginfo_t info;
	struct user_struct *user;
};

/* flags values. */
#define SIGQUEUE_PREALLOC	1

struct sigpending {
	struct list_head list;
	sigset_t signal;
};

/*
 * Define some primitives to manipulate sigset_t.
 */

#ifndef __HAVE_ARCH_SIG_BITOPS
#include <linux/bitops.h>

/* We don't use <linux/bitops.h> for these because there is no need to
   be atomic.  */
static inline void sigaddset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		set->sig[0] |= 1UL << sig;
	else
		set->sig[sig / _NSIG_BPW] |= 1UL << (sig % _NSIG_BPW);
}

static inline void sigdelset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		set->sig[0] &= ~(1UL << sig);
	else
		set->sig[sig / _NSIG_BPW] &= ~(1UL << (sig % _NSIG_BPW));
}

static inline int sigismember(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	if (_NSIG_WORDS == 1)
		return 1 & (set->sig[0] >> sig);
	else
		return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW));
}

static inline int sigfindinword(unsigned long word)
{
	return ffz(~word);
}

#endif /* __HAVE_ARCH_SIG_BITOPS */

static inline int sigisemptyset(sigset_t *set)
{
	extern void _NSIG_WORDS_is_unsupported_size(void);
	switch (_NSIG_WORDS) {
	case 4:
		return (set->sig[3] | set->sig[2] |
			set->sig[1] | set->sig[0]) == 0;
	case 2:
		return (set->sig[1] | set->sig[0]) == 0;
	case 1:
		return set->sig[0] == 0;
	default:
		_NSIG_WORDS_is_unsupported_size();
		return 0;
	}
}

#define sigmask(sig)	(1UL << ((sig) - 1))

#ifndef __HAVE_ARCH_SIG_SETOPS
#include <linux/string.h>

#define _SIG_SET_BINOP(name, op)					\
static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \
{									\
	extern void _NSIG_WORDS_is_unsupported_size(void);		\
	unsigned long a0, a1, a2, a3, b0, b1, b2, b3;			\
									\
	switch (_NSIG_WORDS) {						\
	    case 4:							\
		a3 = a->sig[3]; a2 = a->sig[2];				\
		b3 = b->sig[3]; b2 = b->sig[2];				\
		r->sig[3] = op(a3, b3);					\
		r->sig[2] = op(a2, b2);					\
	    case 2:							\
		a1 = a->sig[1]; b1 = b->sig[1];				\
		r->sig[1] = op(a1, b1);					\
	    case 1:							\
		a0 = a->sig[0]; b0 = b->sig[0];				\
		r->sig[0] = op(a0, b0);					\
		break;							\
	    default:							\
		_NSIG_WORDS_is_unsupported_size();			\
	}								\
}

#define _sig_or(x,y)	((x) | (y))
_SIG_SET_BINOP(sigorsets, _sig_or)

#define _sig_and(x,y)	((x) & (y))
_SIG_SET_BINOP(sigandsets, _sig_and)

#define _sig_nand(x,y)	((x) & ~(y))
_SIG_SET_BINOP(signandsets, _sig_nand)

#undef _SIG_SET_BINOP
#undef _sig_or
#undef _sig_and
#undef _sig_nand

#define _SIG_SET_OP(name, op)						\
static inline void name(sigset_t *set)					\
{									\
	extern void _NSIG_WORDS_is_unsupported_size(void);		\
									\
	switch (_NSIG_WORDS) {						\
	    case 4: set->sig[3] = op(set->sig[3]);			\
		    set->sig[2] = op(set->sig[2]);			\
	    case 2: set->sig[1] = op(set->sig[1]);			\
	    case 1: set->sig[0] = op(set->sig[0]);			\
		    break;						\
	    default:							\
		_NSIG_WORDS_is_unsupported_size();			\
	}								\
}

#define _sig_not(x)	(~(x))
_SIG_SET_OP(signotset, _sig_not)

#undef _SIG_SET_OP
#undef _sig_not

static inline void sigemptyset(sigset_t *set)
{
	switch (_NSIG_WORDS) {
	default:
		memset(set, 0, sizeof(sigset_t));
		break;
	case 2: set->sig[1] = 0;
	case 1:	set->sig[0] = 0;
		break;
	}
}

static inline void sigfillset(sigset_t *set)
{
	switch (_NSIG_WORDS) {
	default:
		memset(set, -1, sizeof(sigset_t));
		break;
	case 2: set->sig[1] = -1;
	case 1:	set->sig[0] = -1;
		break;
	}
}

/* Some extensions for manipulating the low 32 signals in particular.  */

static inline void sigaddsetmask(sigset_t *set, unsigned long mask)
{
	set->sig[0] |= mask;
}

static inline void sigdelsetmask(sigset_t *set, unsigned long mask)
{
	set->sig[0] &= ~mask;
}

static inline int sigtestsetmask(sigset_t *set, unsigned long mask)
{
	return (set->sig[0] & mask) != 0;
}

static inline void siginitset(sigset_t *set, unsigned long mask)
{
	set->sig[0] = mask;
	switch (_NSIG_WORDS) {
	default:
		memset(&set->sig[1], 0, sizeof(long)*(_NSIG_WORDS-1));
		break;
	case 2: set->sig[1] = 0;
	case 1: ;
	}
}

static inline void siginitsetinv(sigset_t *set, unsigned long mask)
{
	set->sig[0] = ~mask;
	switch (_NSIG_WORDS) {
	default:
		memset(&set->sig[1], -1, sizeof(long)*(_NSIG_WORDS-1));
		break;
	case 2: set->sig[1] = -1;
	case 1: ;
	}
}

#endif /* __HAVE_ARCH_SIG_SETOPS */

static inline void init_sigpending(struct sigpending *sig)
{
	sigemptyset(&sig->signal);
	INIT_LIST_HEAD(&sig->list);
}

extern void flush_sigqueue(struct sigpending *queue);

/* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */
static inline int valid_signal(unsigned long sig)
{
	return sig <= _NSIG ? 1 : 0;
}

extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p);
extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *);
extern long do_sigpending(void __user *, unsigned long);
extern int sigprocmask(int, sigset_t *, sigset_t *);

struct pt_regs;
extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie);

extern struct kmem_cache *sighand_cachep;

#endif /* __KERNEL__ */

#endif /* _LINUX_SIGNAL_H */