1 /* __sig_atomic_t, __sigset_t, and related definitions. Linux version.
2 Copyright (C) 1991, 1992, 1994, 1996, 1997 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19 #ifndef _SIGSET_H_types
20 # define _SIGSET_H_types 1
21
22 typedef int __sig_atomic_t;
23
24 /* A 'sigset_t' has a bit for each signal.
25 * glibc has space for 1024 signals (!), but most arches supported
26 * by Linux have 64 signals, and only MIPS has 128.
27 * There seems to be some historical baggage in sparc[64]
28 * where they might have (or had in the past) 32 signals only,
29 * I hope it's irrelevant now.
30 * Signal 0 does not exist, so we have signals 1..64, not 0..63.
31 * In uclibc, kernel and userspace sigset_t is always the same.
32 * BTW, struct sigaction is also the same on kernel and userspace side.
33 */
34 #if defined(__mips__)
35 # define _SIGSET_NWORDS (128 / (8 * sizeof (unsigned long)))
36 #else
37 # define _SIGSET_NWORDS (64 / (8 * sizeof (unsigned long)))
38 #endif
39 typedef struct {
40 unsigned long __val[_SIGSET_NWORDS];
41 } __sigset_t;
42
43 #endif
44
45
46 /* We only want to define these functions if <signal.h> was actually
47 included; otherwise we were included just to define the types. Since we
48 are namespace-clean, it wouldn't hurt to define extra macros. But
49 trouble can be caused by functions being defined (e.g., any global
50 register vars declared later will cause compilation errors). */
51
52 #if !defined _SIGSET_H_fns && defined _SIGNAL_H
53 # define _SIGSET_H_fns 1
54
55 # ifndef _EXTERN_INLINE
56 # define _EXTERN_INLINE __extern_inline
57 # endif
58
59 /* Return a mask that includes the bit for SIG only. */
60 /* Unsigned cast ensures shift/mask insns are used. */
61 # define __sigmask(sig) \
62 (((unsigned long) 1) << ((unsigned)((sig) - 1) % (8 * sizeof (unsigned long))))
63
64 /* Return the word index for SIG. */
65 # define __sigword(sig) ((unsigned)((sig) - 1) / (8 * sizeof (unsigned long)))
66
67 /* gcc 4.3.1 is not clever enough to optimize for _SIGSET_NWORDS == 1 and 2,
68 * which are about the only values which can be there */
69
70 # if defined __GNUC__ && __GNUC__ >= 2
71 # define __sigemptyset(set) \
72 (__extension__ ({ \
73 sigset_t *__set = (set); \
74 if (_SIGSET_NWORDS <= 2) { \
75 __set->__val[0] = 0; \
76 if (_SIGSET_NWORDS == 2) \
77 __set->__val[1] = 0; \
78 } else { \
79 int __cnt = _SIGSET_NWORDS; \
80 while (--__cnt >= 0) __set->__val[__cnt] = 0; \
81 } \
82 0; \
83 }))
84 # define __sigfillset(set) \
85 (__extension__ ({ \
86 sigset_t *__set = (set); \
87 if (_SIGSET_NWORDS <= 2) { \
88 __set->__val[0] = ~0UL; \
89 if (_SIGSET_NWORDS == 2) \
90 __set->__val[1] = ~0UL; \
91 } else { \
92 int __cnt = _SIGSET_NWORDS; \
93 while (--__cnt >= 0) __set->__val[__cnt] = ~0UL; \
94 } \
95 0; \
96 }))
97
98 # ifdef __USE_GNU
99 /* The POSIX does not specify for handling the whole signal set in one
100 command. This is often wanted and so we define three more functions
101 here. */
102 # define __sigisemptyset(set) \
103 (__extension__ ({ \
104 long __ret; \
105 const sigset_t *__set = (set); \
106 if (_SIGSET_NWORDS == 1) { \
107 __ret = __set->__val[0]; \
108 } else if (_SIGSET_NWORDS == 2) { \
109 __ret = __set->__val[0] | __set->__val[1]; \
110 } else { \
111 int __cnt = _SIGSET_NWORDS; \
112 __ret = __set->__val[--__cnt]; \
113 while (!__ret && --__cnt >= 0) \
114 __ret = __set->__val[__cnt]; \
115 } \
116 __ret == 0; \
117 }))
118 # define __sigandset(dest, left, right) \
119 (__extension__ ({ \
120 sigset_t *__dest = (dest); \
121 const sigset_t *__left = (left); \
122 const sigset_t *__right = (right); \
123 if (_SIGSET_NWORDS <= 2) { \
124 __dest->__val[0] = __left->__val[0] & __right->__val[0];\
125 if (_SIGSET_NWORDS == 2) \
126 __dest->__val[1] = __left->__val[1] & __right->__val[1];\
127 } else { \
128 int __cnt = _SIGSET_NWORDS; \
129 while (--__cnt >= 0) \
130 __dest->__val[__cnt] = (__left->__val[__cnt] \
131 & __right->__val[__cnt]); \
132 } \
133 0; \
134 }))
135 # define __sigorset(dest, left, right) \
136 (__extension__ ({ \
137 sigset_t *__dest = (dest); \
138 const sigset_t *__left = (left); \
139 const sigset_t *__right = (right); \
140 if (_SIGSET_NWORDS <= 2) { \
141 __dest->__val[0] = __left->__val[0] | __right->__val[0];\
142 if (_SIGSET_NWORDS == 2) \
143 __dest->__val[1] = __left->__val[1] | __right->__val[1];\
144 } else { \
145 int __cnt = _SIGSET_NWORDS; \
146 while (--__cnt >= 0) \
147 __dest->__val[__cnt] = (__left->__val[__cnt] \
148 | __right->__val[__cnt]); \
149 } \
150 0; \
151 }))
152 # endif
153 # endif
154
155 /* These functions needn't check for a bogus signal number -- error
156 checking is done in the non __ versions. */
157
158 extern int __sigismember (const __sigset_t *, int);
159 libc_hidden_proto(__sigismember)
160 extern void __sigaddset (__sigset_t *, int);
161 libc_hidden_proto(__sigaddset)
162 extern void __sigdelset (__sigset_t *, int);
163 libc_hidden_proto(__sigdelset)
164
165 # ifdef __USE_EXTERN_INLINES
166 # define __SIGSETFN(RET_TYPE, NAME, BODY, CONST) \
167 _EXTERN_INLINE RET_TYPE \
168 NAME (CONST __sigset_t *__set, int __sig) \
169 { \
170 unsigned long __mask = __sigmask (__sig); \
171 unsigned __word = __sigword (__sig); \
172 BODY; \
173 }
174
175 __SIGSETFN (int, __sigismember, return (__set->__val[__word] & __mask) ? 1 : 0,
176 const)
177 __SIGSETFN (void, __sigaddset, (__set->__val[__word] |= __mask), )
178 __SIGSETFN (void, __sigdelset, (__set->__val[__word] &= ~__mask), )
179
180 # undef __SIGSETFN
181 # endif
182
183 # ifdef _LIBC
184 /* It's far too much PITA to __USE_EXTERN_INLINES from within libc.
185 * Especially since we want to inline only calls with const sig,
186 * but __USE_EXTERN_INLINES will inline all calls!
187 */
188 static __always_inline unsigned long
const_sigismember(const __sigset_t * set,int sig)189 const_sigismember(const __sigset_t *set, int sig)
190 {
191 unsigned long mask = __sigmask(sig);
192 unsigned word = __sigword(sig);
193 return (set->__val[word] & mask);
194 }
195 # define __sigismember(set, sig) \
196 (__builtin_constant_p(sig) ? (const_sigismember(set, sig) != 0) : __sigismember(set, sig))
197 static __always_inline void
const_sigaddset(__sigset_t * set,int sig)198 const_sigaddset(__sigset_t *set, int sig)
199 {
200 unsigned long mask = __sigmask(sig);
201 unsigned word = __sigword(sig);
202 set->__val[word] |= mask;
203 }
204 # define __sigaddset(set, sig) \
205 (__builtin_constant_p(sig) ? const_sigaddset(set, sig) : __sigaddset(set, sig))
206 static __always_inline void
const_sigdelset(__sigset_t * set,int sig)207 const_sigdelset(__sigset_t *set, int sig)
208 {
209 unsigned long mask = __sigmask(sig);
210 unsigned word = __sigword(sig);
211 set->__val[word] &= ~mask;
212 }
213 # define __sigdelset(set, sig) \
214 (__builtin_constant_p(sig) ? const_sigdelset(set, sig) : __sigdelset(set, sig))
215 # endif
216
217 #endif /* ! _SIGSET_H_fns. */
218