1 /*

2 * Copyright (c) 2004 Gunnar Ritter

3 *

4 * This software is provided 'as-is', without any express or implied

5 * warranty. In no event will the authors be held liable for any damages

6 * arising from the use of this software.

7 *

8 * Permission is granted to anyone to use this software for any purpose,

9 * including commercial applications, and to alter it and redistribute

10 * it freely, subject to the following restrictions:

11 *

12 * 1. The origin of this software must not be misrepresented; you must not

13 * claim that you wrote the original software. If you use this software

14 * in a product, an acknowledgment in the product documentation would be

15 * appreciated but is not required.

16 *

17 * 2. Altered source versions must be plainly marked as such, and must not be

18 * misrepresented as being the original software.

19 *

20 * 3. This notice may not be removed or altered from any source distribution.

21 */

22 /* Sccsid @(#)sigset.c 1.7 (gritter) 1/22/06 */

23

24 #if defined (__FreeBSD__) || defined (__dietlibc__) || defined (__NetBSD__) || \

25 defined (__OpenBSD__) || defined (__DragonFly__) || defined (__APPLE__)

26 #include <signal.h>

27 #include "sigset.h"

28

29 void (*sigset(int sig, void (*func)(int)))(int)

30 {

31 struct sigaction nact, oact;

32 sigset_t nset, oset;

33

34 if (sig <= 0)

35 return SIG_ERR;

36 sigemptyset(&nset);

37 sigaddset(&nset, sig);

38 if (sigprocmask(func==SIG_HOLD?SIG_BLOCK:SIG_UNBLOCK, &nset, &oset) < 0)

39 return SIG_ERR;

40 nact.sa_handler = func;

41 nact.sa_flags = 0;

42 if (sig == SIGCHLD && func == SIG_IGN)

43 nact.sa_flags |= SA_NOCLDSTOP|SA_NOCLDWAIT;

44 sigemptyset(&nact.sa_mask);

45 sigaddset(&nact.sa_mask, sig);

46 if (sigaction(sig, func==SIG_HOLD?(struct sigaction *)0:&nact, &oact)

47 == -1)

48 return SIG_ERR;

49 if (sigismember(&oset, sig))

50 return SIG_HOLD;

51 else

52 return (oact.sa_handler);

53 }

54 #endif /* __FreeBSD__ || __dietlibc__ || __NetBSD__ || __OpenBSD__ ||

55 __DragonFly__ || __APPLE__ */