nuttx/include/signal.h

/************************************************************
 * signal.h
 *
 *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name Gregory Nutt nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ************************************************************/

#ifndef __SIGNAL_H
#define __SIGNAL_H

/************************************************************
 * Included Files
 ************************************************************/

#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <time.h>      /* Needed for struct timespec */
#include <sys/types.h> /* Needed for, e.g., sigset_t */

/************************************************************
 * Compilations Switches
 ************************************************************/

/************************************************************
 * Definitions
 ************************************************************/

/* Signal set management definitions and macros. */

#define NULL_SIGNAL_SET ((sigset_t)0x00000000)
#define ALL_SIGNAL_SET  ((sigset_t)0xffffffff)
#define MIN_SIGNO       0
#define MAX_SIGNO       31
#define GOOD_SIGNO(s)   (((s)>=MIN_SIGNO)&&((s)<=MAX_SIGNO))
#define SIGNO2SET(s)    ((sigset_t)1 << (s))

/* sigprocmask() "how" definitions.  Only one of the following
 * can be specified:
 */

#define SIG_BLOCK       1
#define SIG_UNBLOCK     2
#define SIG_SETMASK     3

/* struct sigaction flag values */

#define SA_NOCLDSTOP    1 /* Do not generate SIGCHILD when
                           * children stop (ignored) */
#define SA_SIGINFO      2 /* Invoke the signal-catching function
                           * with 3 args instead of 1
                           * (always assumed) */

/* Dummy value for the sigev_notify field of struct sigevent */

#define SIGEV_SIGNAL 0 

/* These are the possible values of the signfo si_code field */

#define SI_QUEUE   0 /* Signal sent from sigqueue */
#define SI_MESGQ   1 /* Signal generated by arrival of a message on an
                      * empty message queue */
#define SI_NOWAIT  2 /* Signal already pending -- don't know how sent */
#define SI_TIMEOUT 3 /* No-signal, unblocked by timeout */

/************************************************************
 * Global Type Declarations
 ************************************************************/

/* This defines a set of 32 signals (numbered 0 through 31). */

typedef uint32 sigset_t;

/* This defines the type of the siginfo si_value field */

union sigval
{
  int   sival_int;
  void *sival_ptr;
};

/* The following types is used to pass parameters to/from
 * signal handlers
 */

typedef struct siginfo
{
  int          si_signo;
  int          si_code;
  union sigval si_value;
} siginfo_t;

/* The following structure defines the action to take for given signal */

struct sigaction
{
  union
  {
    void (*_sa_handler)(int);
    void (*_sa_sigaction)(int, FAR siginfo_t *, FAR void *);
  } sa_u;
  sigset_t         sa_mask;
  int              sa_flags;
};
#define sa_handler   sa_u._sa_handler
#define sa_sigaction sa_u._sa_sigaction

/************************************************************
 * Global Variables
 ************************************************************/

/************************************************************
 * Global Function Prototypes
 ************************************************************/

#ifdef __cplusplus
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif

EXTERN int sigemptyset(sigset_t *set);
EXTERN int sigfillset(sigset_t *set);
EXTERN int sigaddset(sigset_t *set, int signo);
EXTERN int sigdelset(sigset_t *set, int signo);
EXTERN int sigismember(const sigset_t *set, int signo);
EXTERN int sigaction(int sig,
		     const struct sigaction *act,
		     struct sigaction *oact);
EXTERN int sigprocmask(int how, const sigset_t *set,
                       sigset_t *oset);
EXTERN int sigpending(sigset_t *set);
EXTERN int sigsuspend(const sigset_t *sigmask);
EXTERN int sigwaitinfo(const sigset_t *set,
		       struct siginfo *value);
EXTERN int sigtimedwait(const sigset_t *set,
			struct siginfo *value,
			const struct timespec *timeout);
#ifdef CONFIG_CAN_PASS_STRUCTS
EXTERN int sigqueue(int pid, int signo,
		    const union sigval value);
#else
EXTERN int sigqueue(int pid, int signo, void *sival_ptr);
#endif

#undef EXTERN
#ifdef __cplusplus
}
#endif

#endif /* __SIGNAL_H */