1. 根目录:
2. include
3. uapi
4. asm-generic
5. signal.h

#ifndef _UAPI__ASM_GENERIC_SIGNAL_H
#define _UAPI__ASM_GENERIC_SIGNAL_H

#include <linux/types.h>

#define _NSIG		64
#define _NSIG_BPW	__BITS_PER_LONG
#define _NSIG_WORDS	(_NSIG / _NSIG_BPW)

#define SIGHUP		 1
#define SIGINT		 2
#define SIGQUIT		 3
#define SIGILL		 4
#define SIGTRAP		 5
#define SIGABRT		 6
#define SIGIOT		 6
#define SIGBUS		 7
#define SIGFPE		 8
#define SIGKILL		 9
#define SIGUSR1		10
#define SIGSEGV		11
#define SIGUSR2		12
#define SIGPIPE		13
#define SIGALRM		14
#define SIGTERM		15
#define SIGSTKFLT	16
#define SIGCHLD		17
#define SIGCONT		18
#define SIGSTOP		19
#define SIGTSTP		20
#define SIGTTIN		21
#define SIGTTOU		22
#define SIGURG		23
#define SIGXCPU		24
#define SIGXFSZ		25
#define SIGVTALRM	26
#define SIGPROF		27
#define SIGWINCH	28
#define SIGIO		29
#define SIGPOLL		SIGIO
/*
#define SIGLOST		29
*/
#define SIGPWR		30
#define SIGSYS		31
#define	SIGUNUSED	31

/* These should not be considered constants from userland.  */
#define SIGRTMIN	32
#ifndef SIGRTMAX
#define SIGRTMAX	_NSIG
#endif

/*
 * SA_FLAGS values:
 *
 * SA_ONSTACK indicates that a registered stack_t will be used.
 * SA_RESTART flag to get restarting signals (which were the default long ago)
 * SA_NOCLDSTOP flag to turn off SIGCHLD when children stop.
 * SA_RESETHAND clears the handler when the signal is delivered.
 * SA_NOCLDWAIT flag on SIGCHLD to inhibit zombies.
 * SA_NODEFER prevents the current signal from being masked in the handler.
 *
 * SA_ONESHOT and SA_NOMASK are the historical Linux names for the Single
 * Unix names RESETHAND and NODEFER respectively.
 */
#define SA_NOCLDSTOP	0x00000001
#define SA_NOCLDWAIT	0x00000002
#define SA_SIGINFO	0x00000004
#define SA_ONSTACK	0x08000000
#define SA_RESTART	0x10000000
#define SA_NODEFER	0x40000000
#define SA_RESETHAND	0x80000000

#define SA_NOMASK	SA_NODEFER
#define SA_ONESHOT	SA_RESETHAND

/*
 * New architectures should not define the obsolete
 *	SA_RESTORER	0x04000000
 */

#define MINSIGSTKSZ	2048
#define SIGSTKSZ	8192

#ifndef __ASSEMBLY__
typedef struct {
	unsigned long sig[_NSIG_WORDS];
} sigset_t;

/* not actually used, but required for linux/syscalls.h */
typedef unsigned long old_sigset_t;

#include <asm-generic/signal-defs.h>

#ifdef SA_RESTORER
#define __ARCH_HAS_SA_RESTORER
#endif

#ifndef __KERNEL__
struct sigaction {
	__sighandler_t sa_handler;
	unsigned long sa_flags;
#ifdef SA_RESTORER
	__sigrestore_t sa_restorer;
#endif
	sigset_t sa_mask;		/* mask last for extensibility */
};
#endif

typedef struct sigaltstack {
	void __user *ss_sp;
	int ss_flags;
	size_t ss_size;
} stack_t;

#endif /* __ASSEMBLY__ */

#endif /* _UAPI__ASM_GENERIC_SIGNAL_H */