1 #ifndef _LINUX_SIGNAL_H 2 #define _LINUX_SIGNAL_H 3 4 #include <asm/signal.h> 5 #include <asm/siginfo.h> 6 7 #ifdef __KERNEL__ 8 #include <linux/list.h> 9 10 /* for sysctl */ 11 extern int print_fatal_signals; 12 /* 13 * Real Time signals may be queued. 14 */ 15 16 struct sigqueue { 17 struct list_head list; 18 int flags; 19 siginfo_t info; 20 struct user_struct *user; 21 }; 22 23 /* flags values. */ 24 #define SIGQUEUE_PREALLOC 1 25 26 struct sigpending { 27 struct list_head list; 28 sigset_t signal; 29 }; 30 31 /* 32 * Define some primitives to manipulate sigset_t. 33 */ 34 35 #ifndef __HAVE_ARCH_SIG_BITOPS 36 #include <linux/bitops.h> 37 38 /* We don't use <linux/bitops.h> for these because there is no need to 39 be atomic. */ 40 static inline void sigaddset(sigset_t *set, int _sig) 41 { 42 unsigned long sig = _sig - 1; 43 if (_NSIG_WORDS == 1) 44 set->sig[0] |= 1UL << sig; 45 else 46 set->sig[sig / _NSIG_BPW] |= 1UL << (sig % _NSIG_BPW); 47 } 48 49 static inline void sigdelset(sigset_t *set, int _sig) 50 { 51 unsigned long sig = _sig - 1; 52 if (_NSIG_WORDS == 1) 53 set->sig[0] &= ~(1UL << sig); 54 else 55 set->sig[sig / _NSIG_BPW] &= ~(1UL << (sig % _NSIG_BPW)); 56 } 57 58 static inline int sigismember(sigset_t *set, int _sig) 59 { 60 unsigned long sig = _sig - 1; 61 if (_NSIG_WORDS == 1) 62 return 1 & (set->sig[0] >> sig); 63 else 64 return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW)); 65 } 66 67 static inline int sigfindinword(unsigned long word) 68 { 69 return ffz(~word); 70 } 71 72 #endif /* __HAVE_ARCH_SIG_BITOPS */ 73 74 static inline int sigisemptyset(sigset_t *set) 75 { 76 extern void _NSIG_WORDS_is_unsupported_size(void); 77 switch (_NSIG_WORDS) { 78 case 4: 79 return (set->sig[3] | set->sig[2] | 80 set->sig[1] | set->sig[0]) == 0; 81 case 2: 82 return (set->sig[1] | set->sig[0]) == 0; 83 case 1: 84 return set->sig[0] == 0; 85 default: 86 _NSIG_WORDS_is_unsupported_size(); 87 return 0; 88 } 89 } 90 91 #define sigmask(sig) (1UL << ((sig) - 1)) 92 93 #ifndef __HAVE_ARCH_SIG_SETOPS 94 #include <linux/string.h> 95 96 #define _SIG_SET_BINOP(name, op) \ 97 static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \ 98 { \ 99 extern void _NSIG_WORDS_is_unsupported_size(void); \ 100 unsigned long a0, a1, a2, a3, b0, b1, b2, b3; \ 101 \ 102 switch (_NSIG_WORDS) { \ 103 case 4: \ 104 a3 = a->sig[3]; a2 = a->sig[2]; \ 105 b3 = b->sig[3]; b2 = b->sig[2]; \ 106 r->sig[3] = op(a3, b3); \ 107 r->sig[2] = op(a2, b2); \ 108 case 2: \ 109 a1 = a->sig[1]; b1 = b->sig[1]; \ 110 r->sig[1] = op(a1, b1); \ 111 case 1: \ 112 a0 = a->sig[0]; b0 = b->sig[0]; \ 113 r->sig[0] = op(a0, b0); \ 114 break; \ 115 default: \ 116 _NSIG_WORDS_is_unsupported_size(); \ 117 } \ 118 } 119 120 #define _sig_or(x,y) ((x) | (y)) 121 _SIG_SET_BINOP(sigorsets, _sig_or) 122 123 #define _sig_and(x,y) ((x) & (y)) 124 _SIG_SET_BINOP(sigandsets, _sig_and) 125 126 #define _sig_nand(x,y) ((x) & ~(y)) 127 _SIG_SET_BINOP(signandsets, _sig_nand) 128 129 #undef _SIG_SET_BINOP 130 #undef _sig_or 131 #undef _sig_and 132 #undef _sig_nand 133 134 #define _SIG_SET_OP(name, op) \ 135 static inline void name(sigset_t *set) \ 136 { \ 137 extern void _NSIG_WORDS_is_unsupported_size(void); \ 138 \ 139 switch (_NSIG_WORDS) { \ 140 case 4: set->sig[3] = op(set->sig[3]); \ 141 set->sig[2] = op(set->sig[2]); \ 142 case 2: set->sig[1] = op(set->sig[1]); \ 143 case 1: set->sig[0] = op(set->sig[0]); \ 144 break; \ 145 default: \ 146 _NSIG_WORDS_is_unsupported_size(); \ 147 } \ 148 } 149 150 #define _sig_not(x) (~(x)) 151 _SIG_SET_OP(signotset, _sig_not) 152 153 #undef _SIG_SET_OP 154 #undef _sig_not 155 156 static inline void sigemptyset(sigset_t *set) 157 { 158 switch (_NSIG_WORDS) { 159 default: 160 memset(set, 0, sizeof(sigset_t)); 161 break; 162 case 2: set->sig[1] = 0; 163 case 1: set->sig[0] = 0; 164 break; 165 } 166 } 167 168 static inline void sigfillset(sigset_t *set) 169 { 170 switch (_NSIG_WORDS) { 171 default: 172 memset(set, -1, sizeof(sigset_t)); 173 break; 174 case 2: set->sig[1] = -1; 175 case 1: set->sig[0] = -1; 176 break; 177 } 178 } 179 180 /* Some extensions for manipulating the low 32 signals in particular. */ 181 182 static inline void sigaddsetmask(sigset_t *set, unsigned long mask) 183 { 184 set->sig[0] |= mask; 185 } 186 187 static inline void sigdelsetmask(sigset_t *set, unsigned long mask) 188 { 189 set->sig[0] &= ~mask; 190 } 191 192 static inline int sigtestsetmask(sigset_t *set, unsigned long mask) 193 { 194 return (set->sig[0] & mask) != 0; 195 } 196 197 static inline void siginitset(sigset_t *set, unsigned long mask) 198 { 199 set->sig[0] = mask; 200 switch (_NSIG_WORDS) { 201 default: 202 memset(&set->sig[1], 0, sizeof(long)*(_NSIG_WORDS-1)); 203 break; 204 case 2: set->sig[1] = 0; 205 case 1: ; 206 } 207 } 208 209 static inline void siginitsetinv(sigset_t *set, unsigned long mask) 210 { 211 set->sig[0] = ~mask; 212 switch (_NSIG_WORDS) { 213 default: 214 memset(&set->sig[1], -1, sizeof(long)*(_NSIG_WORDS-1)); 215 break; 216 case 2: set->sig[1] = -1; 217 case 1: ; 218 } 219 } 220 221 #endif /* __HAVE_ARCH_SIG_SETOPS */ 222 223 static inline void init_sigpending(struct sigpending *sig) 224 { 225 sigemptyset(&sig->signal); 226 INIT_LIST_HEAD(&sig->list); 227 } 228 229 extern void flush_sigqueue(struct sigpending *queue); 230 231 /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */ 232 static inline int valid_signal(unsigned long sig) 233 { 234 return sig <= _NSIG ? 1 : 0; 235 } 236 237 extern int next_signal(struct sigpending *pending, sigset_t *mask); 238 extern int do_send_sig_info(int sig, struct siginfo *info, 239 struct task_struct *p, bool group); 240 extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p); 241 extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *); 242 extern long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, 243 siginfo_t *info); 244 extern long do_sigpending(void __user *, unsigned long); 245 extern int sigprocmask(int, sigset_t *, sigset_t *); 246 extern int show_unhandled_signals; 247 248 struct pt_regs; 249 extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie); 250 extern void exit_signals(struct task_struct *tsk); 251 252 extern struct kmem_cache *sighand_cachep; 253 254 int unhandled_signal(struct task_struct *tsk, int sig); 255 256 /* 257 * In POSIX a signal is sent either to a specific thread (Linux task) 258 * or to the process as a whole (Linux thread group). How the signal 259 * is sent determines whether it's to one thread or the whole group, 260 * which determines which signal mask(s) are involved in blocking it 261 * from being delivered until later. When the signal is delivered, 262 * either it's caught or ignored by a user handler or it has a default 263 * effect that applies to the whole thread group (POSIX process). 264 * 265 * The possible effects an unblocked signal set to SIG_DFL can have are: 266 * ignore - Nothing Happens 267 * terminate - kill the process, i.e. all threads in the group, 268 * similar to exit_group. The group leader (only) reports 269 * WIFSIGNALED status to its parent. 270 * coredump - write a core dump file describing all threads using 271 * the same mm and then kill all those threads 272 * stop - stop all the threads in the group, i.e. TASK_STOPPED state 273 * 274 * SIGKILL and SIGSTOP cannot be caught, blocked, or ignored. 275 * Other signals when not blocked and set to SIG_DFL behaves as follows. 276 * The job control signals also have other special effects. 277 * 278 * +--------------------+------------------+ 279 * | POSIX signal | default action | 280 * +--------------------+------------------+ 281 * | SIGHUP | terminate | 282 * | SIGINT | terminate | 283 * | SIGQUIT | coredump | 284 * | SIGILL | coredump | 285 * | SIGTRAP | coredump | 286 * | SIGABRT/SIGIOT | coredump | 287 * | SIGBUS | coredump | 288 * | SIGFPE | coredump | 289 * | SIGKILL | terminate(+) | 290 * | SIGUSR1 | terminate | 291 * | SIGSEGV | coredump | 292 * | SIGUSR2 | terminate | 293 * | SIGPIPE | terminate | 294 * | SIGALRM | terminate | 295 * | SIGTERM | terminate | 296 * | SIGCHLD | ignore | 297 * | SIGCONT | ignore(*) | 298 * | SIGSTOP | stop(*)(+) | 299 * | SIGTSTP | stop(*) | 300 * | SIGTTIN | stop(*) | 301 * | SIGTTOU | stop(*) | 302 * | SIGURG | ignore | 303 * | SIGXCPU | coredump | 304 * | SIGXFSZ | coredump | 305 * | SIGVTALRM | terminate | 306 * | SIGPROF | terminate | 307 * | SIGPOLL/SIGIO | terminate | 308 * | SIGSYS/SIGUNUSED | coredump | 309 * | SIGSTKFLT | terminate | 310 * | SIGWINCH | ignore | 311 * | SIGPWR | terminate | 312 * | SIGRTMIN-SIGRTMAX | terminate | 313 * +--------------------+------------------+ 314 * | non-POSIX signal | default action | 315 * +--------------------+------------------+ 316 * | SIGEMT | coredump | 317 * +--------------------+------------------+ 318 * 319 * (+) For SIGKILL and SIGSTOP the action is "always", not just "default". 320 * (*) Special job control effects: 321 * When SIGCONT is sent, it resumes the process (all threads in the group) 322 * from TASK_STOPPED state and also clears any pending/queued stop signals 323 * (any of those marked with "stop(*)"). This happens regardless of blocking, 324 * catching, or ignoring SIGCONT. When any stop signal is sent, it clears 325 * any pending/queued SIGCONT signals; this happens regardless of blocking, 326 * catching, or ignored the stop signal, though (except for SIGSTOP) the 327 * default action of stopping the process may happen later or never. 328 */ 329 330 #ifdef SIGEMT 331 #define SIGEMT_MASK rt_sigmask(SIGEMT) 332 #else 333 #define SIGEMT_MASK 0 334 #endif 335 336 #if SIGRTMIN > BITS_PER_LONG 337 #define rt_sigmask(sig) (1ULL << ((sig)-1)) 338 #else 339 #define rt_sigmask(sig) sigmask(sig) 340 #endif 341 #define siginmask(sig, mask) (rt_sigmask(sig) & (mask)) 342 343 #define SIG_KERNEL_ONLY_MASK (\ 344 rt_sigmask(SIGKILL) | rt_sigmask(SIGSTOP)) 345 346 #define SIG_KERNEL_STOP_MASK (\ 347 rt_sigmask(SIGSTOP) | rt_sigmask(SIGTSTP) | \ 348 rt_sigmask(SIGTTIN) | rt_sigmask(SIGTTOU) ) 349 350 #define SIG_KERNEL_COREDUMP_MASK (\ 351 rt_sigmask(SIGQUIT) | rt_sigmask(SIGILL) | \ 352 rt_sigmask(SIGTRAP) | rt_sigmask(SIGABRT) | \ 353 rt_sigmask(SIGFPE) | rt_sigmask(SIGSEGV) | \ 354 rt_sigmask(SIGBUS) | rt_sigmask(SIGSYS) | \ 355 rt_sigmask(SIGXCPU) | rt_sigmask(SIGXFSZ) | \ 356 SIGEMT_MASK ) 357 358 #define SIG_KERNEL_IGNORE_MASK (\ 359 rt_sigmask(SIGCONT) | rt_sigmask(SIGCHLD) | \ 360 rt_sigmask(SIGWINCH) | rt_sigmask(SIGURG) ) 361 362 #define sig_kernel_only(sig) \ 363 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_ONLY_MASK)) 364 #define sig_kernel_coredump(sig) \ 365 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_COREDUMP_MASK)) 366 #define sig_kernel_ignore(sig) \ 367 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_IGNORE_MASK)) 368 #define sig_kernel_stop(sig) \ 369 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_STOP_MASK)) 370 371 #define sig_user_defined(t, signr) \ 372 (((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) && \ 373 ((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN)) 374 375 #define sig_fatal(t, signr) \ 376 (!siginmask(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \ 377 (t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL) 378 379 void signals_init(void); 380 381 #endif /* __KERNEL__ */ 382 383 #endif /* _LINUX_SIGNAL_H */ 384