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 /* Return a mask that includes the bit for SIG only. */
56 /* Unsigned cast ensures shift/mask insns are used. */
57 # define __sigmask(sig) \
58 (((unsigned long) 1) << ((unsigned)((sig) - 1) % (8 * sizeof (unsigned long))))
59
60 /* Return the word index for SIG. */
61 # define __sigword(sig) ((unsigned)((sig) - 1) / (8 * sizeof (unsigned long)))
62
63 /* gcc 4.3.1 is not clever enough to optimize for _SIGSET_NWORDS == 1 and 2,
64 * which are about the only values which can be there */
65
66 # if defined __GNUC__ && __GNUC__ >= 2
67 # define __sigemptyset(set) \
68 (__extension__ ({ \
69 sigset_t *__set = (set); \
70 if (_SIGSET_NWORDS <= 2) { \
71 __set->__val[0] = 0; \
72 if (_SIGSET_NWORDS == 2) \
73 __set->__val[1] = 0; \
74 } else { \
75 int __cnt = _SIGSET_NWORDS; \
76 while (--__cnt >= 0) __set->__val[__cnt] = 0; \
77 } \
78 0; \
79 }))
80 # define __sigfillset(set) \
81 (__extension__ ({ \
82 sigset_t *__set = (set); \
83 if (_SIGSET_NWORDS <= 2) { \
84 __set->__val[0] = ~0UL; \
85 if (_SIGSET_NWORDS == 2) \
86 __set->__val[1] = ~0UL; \
87 } else { \
88 int __cnt = _SIGSET_NWORDS; \
89 while (--__cnt >= 0) __set->__val[__cnt] = ~0UL; \
90 } \
91 0; \
92 }))
93
94 # ifdef __USE_GNU
95 /* The POSIX does not specify for handling the whole signal set in one
96 command. This is often wanted and so we define three more functions
97 here. */
98 # define __sigisemptyset(set) \
99 (__extension__ ({ \
100 long __ret; \
101 const sigset_t *__set = (set); \
102 if (_SIGSET_NWORDS == 1) { \
103 __ret = __set->__val[0]; \
104 } else if (_SIGSET_NWORDS == 2) { \
105 __ret = __set->__val[0] | __set->__val[1]; \
106 } else { \
107 int __cnt = _SIGSET_NWORDS; \
108 __ret = __set->__val[--__cnt]; \
109 while (!__ret && --__cnt >= 0) \
110 __ret = __set->__val[__cnt]; \
111 } \
112 __ret == 0; \
113 }))
114 # define __sigandset(dest, left, right) \
115 (__extension__ ({ \
116 sigset_t *__dest = (dest); \
117 const sigset_t *__left = (left); \
118 const sigset_t *__right = (right); \
119 if (_SIGSET_NWORDS <= 2) { \
120 __dest->__val[0] = __left->__val[0] & __right->__val[0];\
121 if (_SIGSET_NWORDS == 2) \
122 __dest->__val[1] = __left->__val[1] & __right->__val[1];\
123 } else { \
124 int __cnt = _SIGSET_NWORDS; \
125 while (--__cnt >= 0) \
126 __dest->__val[__cnt] = (__left->__val[__cnt] \
127 & __right->__val[__cnt]); \
128 } \
129 0; \
130 }))
131 # define __sigorset(dest, left, right) \
132 (__extension__ ({ \
133 sigset_t *__dest = (dest); \
134 const sigset_t *__left = (left); \
135 const sigset_t *__right = (right); \
136 if (_SIGSET_NWORDS <= 2) { \
137 __dest->__val[0] = __left->__val[0] | __right->__val[0];\
138 if (_SIGSET_NWORDS == 2) \
139 __dest->__val[1] = __left->__val[1] | __right->__val[1];\
140 } else { \
141 int __cnt = _SIGSET_NWORDS; \
142 while (--__cnt >= 0) \
143 __dest->__val[__cnt] = (__left->__val[__cnt] \
144 | __right->__val[__cnt]); \
145 } \
146 0; \
147 }))
148 # endif
149 # endif
150
151 /* These functions needn't check for a bogus signal number -- error
152 checking is done in the non __ versions. */
153
154 # if !defined __USE_EXTERN_INLINES || defined __PROVIDE_OUT_OF_LINE_SIGSETFN
155 extern int __sigismember (const __sigset_t *, int);
156 libc_hidden_proto(__sigismember)
157 extern int __sigaddset (__sigset_t *, int);
158 libc_hidden_proto(__sigaddset)
159 extern int __sigdelset (__sigset_t *, int);
160 libc_hidden_proto(__sigdelset)
161 # endif
162
163 # ifdef __USE_EXTERN_INLINES
164 # undef _EXTERN_INLINE
165 # ifdef __PROVIDE_OUT_OF_LINE_SIGSETFN
166 # define _EXTERN_INLINE
167 # else /* normal case */
168 /* dropped extern below: otherwise every module with __USE_EXTERN_INLINES
169 * will have its own copy of out-of line function emitted. */
170 # define _EXTERN_INLINE /*extern*/ __always_inline
171 # endif
172 # define __SIGSETFN(NAME, BODY, CONST) \
173 _EXTERN_INLINE int \
174 NAME (CONST __sigset_t *__set, int __sig) \
175 { \
176 unsigned long __mask = __sigmask (__sig); \
177 unsigned __word = __sigword (__sig); \
178 return BODY; \
179 }
180
181 __SIGSETFN (__sigismember, (__set->__val[__word] & __mask) ? 1 : 0, const)
182 __SIGSETFN (__sigaddset, ((__set->__val[__word] |= __mask), 0), )
183 __SIGSETFN (__sigdelset, ((__set->__val[__word] &= ~__mask), 0), )
184
185 # undef __SIGSETFN
186 # endif
187
188 # ifdef _LIBC
189 /* It's far too much PITA to __USE_EXTERN_INLINES from within libc.
190 * Especially since we want to inline only calls with const sig,
191 * but __USE_EXTERN_INLINES will inline all calls!
192 */
193 static __always_inline unsigned long
const_sigismember(const __sigset_t * set,int sig)194 const_sigismember(const __sigset_t *set, int sig)
195 {
196 unsigned long mask = __sigmask(sig);
197 unsigned word = __sigword(sig);
198 return (set->__val[word] & mask);
199 }
200 # define __sigismember(set, sig) \
201 (__builtin_constant_p(sig) ? (const_sigismember(set, sig) != 0) : __sigismember(set, sig))
202 static __always_inline void
const_sigaddset(__sigset_t * set,int sig)203 const_sigaddset(__sigset_t *set, int sig)
204 {
205 unsigned long mask = __sigmask(sig);
206 unsigned word = __sigword(sig);
207 set->__val[word] |= mask;
208 }
209 # define __sigaddset(set, sig) \
210 (__builtin_constant_p(sig) ? (const_sigaddset(set, sig), 0) : __sigaddset(set, sig))
211 static __always_inline void
const_sigdelset(__sigset_t * set,int sig)212 const_sigdelset(__sigset_t *set, int sig)
213 {
214 unsigned long mask = __sigmask(sig);
215 unsigned word = __sigword(sig);
216 set->__val[word] &= ~mask;
217 }
218 # define __sigdelset(set, sig) \
219 (__builtin_constant_p(sig) ? (const_sigdelset(set, sig), 0) : __sigdelset(set, sig))
220 # endif
221
222 #endif /* ! _SIGSET_H_fns. */
223