1 /*      $NetBSD: compat_sigaltstack.h,v 1.2 2007/06/16 20:04:27 dsl Exp $        */
2 
3 /* Wrapper for calling sigaltstack1() from compat (or other) code */
4 
5 /* Maybe these definitions could be global. */
6 #ifdef SCARG_P32
7 /* compat32 */
8 #define	SCARG_COMPAT_PTR(uap,p)	SCARG_P32(uap, p)
9 #define	COMPAT_GET_PTR(p)	NETBSD32PTR64(p)
10 #define	COMPAT_SET_PTR(p, v)	NETBSD32PTR32(p, v)
11 #else
12 /* not a size change */
13 #define	SCARG_COMPAT_PTR(uap,p)	SCARG(uap, p)
14 #define	COMPAT_GET_PTR(p)	(p)
15 #define	COMPAT_SET_PTR(p, v)	((p) = (v))
16 #endif
17 
18 #define compat_sigaltstack(uap, compat_ss, ss_onstack, ss_disable) do { \
19 	struct compat_ss css; \
20 	struct sigaltstack nss, oss; \
21 	int error; \
22 \
23 	if (SCARG_COMPAT_PTR(uap, nss)) { \
24 		error = copyin(SCARG_COMPAT_PTR(uap, nss), &css, sizeof css); \
25 		if (error) \
26 			return error; \
27 		nss.ss_sp = COMPAT_GET_PTR(css.ss_sp); \
28 		nss.ss_size = css.ss_size; \
29 		if (ss_onstack == SS_ONSTACK && ss_disable == SS_DISABLE) \
30 			nss.ss_flags = css.ss_flags; \
31 		else \
32 			nss.ss_flags = \
33 			    (css.ss_flags & ss_onstack ? SS_ONSTACK : 0) \
34 			    | (css.ss_flags & ss_disable ? SS_DISABLE : 0); \
35 	} \
36 \
37 	error = sigaltstack1(l, SCARG_COMPAT_PTR(uap, nss) ? &nss : 0, \
38 				SCARG_COMPAT_PTR(uap, oss) ? &oss : 0); \
39 	if (error) \
40 		return (error); \
41 \
42 	if (SCARG_COMPAT_PTR(uap, oss)) { \
43 		COMPAT_SET_PTR(css.ss_sp, oss.ss_sp); \
44 		css.ss_size = oss.ss_size; \
45 		if (ss_onstack == SS_ONSTACK && ss_disable == SS_DISABLE) \
46 			css.ss_flags = oss.ss_flags; \
47 		else \
48 			css.ss_flags = \
49 			    (oss.ss_flags & SS_ONSTACK ? ss_onstack : 0) \
50 			    | (oss.ss_flags & SS_DISABLE ? ss_disable : 0); \
51 		error = copyout(&css, SCARG_COMPAT_PTR(uap, oss), sizeof(css));\
52 		if (error) \
53 			return (error); \
54 	} \
55 	return (0); \
56 } while (0)
57