text: #ifndef _LINUX_SIGNAL_H
  #define _LINUX_SIGNAL_H
  
  #include <linux/list.h>
  #include <linux/spinlock.h>
  #include <asm/signal.h>
  #include <asm/siginfo.h>
  
  #ifdef __KERNEL__
  
  /*
   * These values of sa_flags are used only by the kernel as part of the
   * irq handling routines.
   *
   * SA_INTERRUPT is also used by the irq handling routines.
   * SA_SHIRQ is for shared interrupt support on PCI and EISA.
   */
  #define SA_PROBE		SA_ONESHOT
  #define SA_SAMPLE_RANDOM	SA_RESTART
  #define SA_SHIRQ		0x04000000
  /*
   * As above, these correspond to the IORESOURCE_IRQ_* defines in
   * linux/ioport.h to select the interrupt line behaviour.  When
   * requesting an interrupt without specifying a SA_TRIGGER, the
   * setting should be assumed to be "as already configured", which
   * may be as per machine or firmware initialisation.
   */
  #define SA_TRIGGER_LOW		0x00000008
  #define SA_TRIGGER_HIGH		0x00000004
  #define SA_TRIGGER_FALLING	0x00000002
  #define SA_TRIGGER_RISING	0x00000001
  #define SA_TRIGGER_MASK	(SA_TRIGGER_HIGH|SA_TRIGGER_LOW|\
  				 SA_TRIGGER_RISING|SA_TRIGGER_FALLING)
  
  /*
   * 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);
  }
  
  /* 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);
  
  #endif /* __KERNEL__ */
  
  #endif /* _LINUX_SIGNAL_H */
  