signal.h revision 266692 
1/*
2 * Copyright (c) 1998-2001 Proofpoint, Inc. and its suppliers.
3 *	All rights reserved.
4 * Copyright (c) 1983, 1995-1997 Eric P. Allman.  All rights reserved.
5 * Copyright (c) 1988, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * By using this file, you agree to the terms and conditions set
9 * forth in the LICENSE file which can be found at the top level of
10 * the sendmail distribution.
11 *
12 *	$Id: signal.h,v 1.17 2013-11-22 20:51:31 ca Exp $
13 */
14
15/*
16**  SIGNAL.H -- libsm (and sendmail) signal facilities
17**		Extracted from sendmail/conf.h and focusing
18**		on signal configuration.
19*/
20
21#ifndef SM_SIGNAL_H
22#define SM_SIGNAL_H 1
23
24#include <sys/types.h>
25#include <limits.h>
26#include <signal.h>
27#include <sm/cdefs.h>
28#include <sm/conf.h>
29
30/*
31**  Critical signal sections
32*/
33
34#define PEND_SIGHUP	0x0001
35#define PEND_SIGINT	0x0002
36#define PEND_SIGTERM	0x0004
37#define PEND_SIGUSR1	0x0008
38
39#define ENTER_CRITICAL()	InCriticalSection++
40
41#define LEAVE_CRITICAL()						\
42do									\
43{									\
44	if (InCriticalSection > 0)					\
45		InCriticalSection--;					\
46} while (0)
47
48#define CHECK_CRITICAL(sig)						\
49do									\
50{									\
51	if (InCriticalSection > 0 && (sig) != 0)			\
52	{								\
53		pend_signal((sig));					\
54		return SIGFUNC_RETURN;					\
55	}								\
56} while (0)
57
58/* variables */
59extern unsigned int	volatile InCriticalSection;	/* >0 if in critical section */
60extern int		volatile PendingSignal;	/* pending signal to resend */
61
62/* functions */
63extern void		pend_signal __P((int));
64
65/* reset signal in case System V semantics */
66#ifdef SYS5SIGNALS
67# define FIX_SYSV_SIGNAL(sig, handler)					\
68{									\
69	if ((sig) != 0)							\
70		(void) sm_signal((sig), (handler));			\
71}
72#else /* SYS5SIGNALS */
73# define FIX_SYSV_SIGNAL(sig, handler)	{ /* EMPTY */ }
74#endif /* SYS5SIGNALS */
75
76extern void		sm_allsignals __P((bool));
77extern int		sm_blocksignal __P((int));
78extern int		sm_releasesignal __P((int));
79extern sigfunc_t	sm_signal __P((int, sigfunc_t));
80extern SIGFUNC_DECL	sm_signal_noop __P((int));
81#endif /* SM_SIGNAL_H */
82