include/sm/signal.h

	signal.h revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * Copyright (c) 1998-2001 Sendmail, Inc. and its suppliers.
 *  All rights reserved.
 * Copyright (c) 1983, 1995-1997 Eric P. Allman.  All rights reserved.
 * Copyright (c) 1988, 1993
 *  The Regents of the University of California.  All rights reserved.
 *
 * By using this file, you agree to the terms and conditions set
 * forth in the LICENSE file which can be found at the top level of
 * the sendmail distribution.
 *
 *  $Id: signal.h,v 1.16 2001/07/20 19:48:21 gshapiro Exp $
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
**  SIGNAL.H -- libsm (and sendmail) signal facilities
**      Extracted from sendmail/conf.h and focusing
**      on signal configuration.
*/

#ifndef SM_SIGNAL_H
#define SM_SIGNAL_H 1

#include <sys/types.h>
#include <limits.h>
#include <signal.h>
#include <sm/cdefs.h>
#include <sm/conf.h>

/*
**  Critical signal sections
*/

#define PEND_SIGHUP 0x0001
#define PEND_SIGINT 0x0002
#define PEND_SIGTERM    0x0004
#define PEND_SIGUSR1    0x0008

#define ENTER_CRITICAL()    InCriticalSection++

#define LEAVE_CRITICAL()                        \
do                                  \
{                                   \
    if (InCriticalSection > 0)                  \
        InCriticalSection--;                    \
} while (0)

#define CHECK_CRITICAL(sig)                     \
do                                  \
{                                   \
    if (InCriticalSection > 0 && (sig) != 0)            \
    {                               \
        pend_signal((sig));                 \
        return SIGFUNC_RETURN;                  \
    }                               \
} while (0)

/* variables */
extern unsigned int volatile InCriticalSection; /* >0 if in critical section */
extern int      volatile PendingSignal; /* pending signal to resend */

/* functions */
extern void     pend_signal __P((int));

/* reset signal in case System V semantics */
#ifdef SYS5SIGNALS
# define FIX_SYSV_SIGNAL(sig, handler)                  \
{                                   \
    if ((sig) != 0)                         \
        (void) sm_signal((sig), (handler));         \
}
#else /* SYS5SIGNALS */
# define FIX_SYSV_SIGNAL(sig, handler)  { /* EMPTY */ }
#endif /* SYS5SIGNALS */

extern void     sm_allsignals __P((bool));
extern int      sm_blocksignal __P((int));
extern int      sm_releasesignal __P((int));
extern sigfunc_t    sm_signal __P((int, sigfunc_t));
extern SIGFUNC_DECL sm_signal_noop __P((int));
#endif /* SM_SIGNAL_H */