lib/signal.in.h

   1 /* A GNU-like <signal.h>.
   2
   3    Copyright (C) 2006-2020 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #if __GNUC__ >= 3
  19 @PRAGMA_SYSTEM_HEADER@
  20 #endif
  21 @PRAGMA_COLUMNS@
  22
  23 #if defined __need_sig_atomic_t || defined __need_sigset_t || defined _GL_ALREADY_INCLUDING_SIGNAL_H || (defined _SIGNAL_H && !defined __SIZEOF_PTHREAD_MUTEX_T)
  24 /* Special invocation convention:
  25    - Inside glibc header files.
  26    - On glibc systems we have a sequence of nested includes
  27      <signal.h> -> <ucontext.h> -> <signal.h>.
  28      In this situation, the functions are not yet declared, therefore we cannot
  29      provide the C++ aliases.
  30    - On glibc systems with GCC 4.3 we have a sequence of nested includes
  31      <csignal> -> </usr/include/signal.h> -> <sys/ucontext.h> -> <signal.h>.
  32      In this situation, some of the functions are not yet declared, therefore
  33      we cannot provide the C++ aliases.  */
  34
  35 # @INCLUDE_NEXT@ @NEXT_SIGNAL_H@
  36
  37 #else
  38 /* Normal invocation convention.  */
  39
  40 #ifndef _@GUARD_PREFIX@_SIGNAL_H
  41
  42 #define _GL_ALREADY_INCLUDING_SIGNAL_H
  43
  44 /* Define pid_t, uid_t.
  45    Also, mingw defines sigset_t not in <signal.h>, but in <sys/types.h>.
  46    On Solaris 10, <signal.h> includes <sys/types.h>, which eventually includes
  47    us; so include <sys/types.h> now, before the second inclusion guard.  */
  48 #include <sys/types.h>
  49
  50 /* The include_next requires a split double-inclusion guard.  */
  51 #@INCLUDE_NEXT@ @NEXT_SIGNAL_H@
  52
  53 #undef _GL_ALREADY_INCLUDING_SIGNAL_H
  54
  55 #ifndef _@GUARD_PREFIX@_SIGNAL_H
  56 #define _@GUARD_PREFIX@_SIGNAL_H
  57
  58 /* Mac OS X 10.3, FreeBSD 6.4, OpenBSD 3.8, OSF/1 4.0, Solaris 2.6, Android
  59    declare pthread_sigmask in <pthread.h>, not in <signal.h>.
  60    But avoid namespace pollution on glibc systems.*/
  61 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
  62     && ((defined __APPLE__ && defined __MACH__) \
  63         || defined __FreeBSD__ || defined __OpenBSD__ || defined __osf__ \
  64         || defined __sun || defined __ANDROID__) \
  65     && ! defined __GLIBC__
  66 # include <pthread.h>
  67 #endif
  68
  69 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
  70
  71 /* The definition of _GL_ARG_NONNULL is copied here.  */
  72
  73 /* The definition of _GL_WARN_ON_USE is copied here.  */
  74
  75 /* On AIX, sig_atomic_t already includes volatile.  C99 requires that
  76    'volatile sig_atomic_t' ignore the extra modifier, but C89 did not.
  77    Hence, redefine this to a non-volatile type as needed.  */
  78 #if ! @HAVE_TYPE_VOLATILE_SIG_ATOMIC_T@
  79 # if !GNULIB_defined_sig_atomic_t
  80 typedef int rpl_sig_atomic_t;
  81 #  undef sig_atomic_t
  82 #  define sig_atomic_t rpl_sig_atomic_t
  83 #  define GNULIB_defined_sig_atomic_t 1
  84 # endif
  85 #endif
  86
  87 /* A set or mask of signals.  */
  88 #if !@HAVE_SIGSET_T@
  89 # if !GNULIB_defined_sigset_t
  90 typedef unsigned int sigset_t;
  91 #  define GNULIB_defined_sigset_t 1
  92 # endif
  93 #endif
  94
  95 /* Define sighandler_t, the type of signal handlers.  A GNU extension.  */
  96 #if !@HAVE_SIGHANDLER_T@
  97 # ifdef __cplusplus
  98 extern "C" {
  99 # endif
 100 # if !GNULIB_defined_sighandler_t
 101 typedef void (*sighandler_t) (int);
 102 #  define GNULIB_defined_sighandler_t 1
 103 # endif
 104 # ifdef __cplusplus
 105 }
 106 # endif
 107 #endif
 108
 109
 110 #if @GNULIB_SIGNAL_H_SIGPIPE@
 111 # ifndef SIGPIPE
 112 /* Define SIGPIPE to a value that does not overlap with other signals.  */
 113 #  define SIGPIPE 13
 114 #  define GNULIB_defined_SIGPIPE 1
 115 /* To actually use SIGPIPE, you also need the gnulib modules 'sigprocmask',
 116    'write', 'stdio'.  */
 117 # endif
 118 #endif
 119
 120
 121 /* Maximum signal number + 1.  */
 122 #ifndef NSIG
 123 # if defined __TANDEM
 124 #  define NSIG 32
 125 # endif
 126 #endif
 127
 128
 129 #if @GNULIB_PTHREAD_SIGMASK@
 130 # if @REPLACE_PTHREAD_SIGMASK@
 131 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 132 #   undef pthread_sigmask
 133 #   define pthread_sigmask rpl_pthread_sigmask
 134 #  endif
 135 _GL_FUNCDECL_RPL (pthread_sigmask, int,
 136                   (int how,
 137                    const sigset_t *restrict new_mask,
 138                    sigset_t *restrict old_mask));
 139 _GL_CXXALIAS_RPL (pthread_sigmask, int,
 140                   (int how,
 141                    const sigset_t *restrict new_mask,
 142                    sigset_t *restrict old_mask));
 143 # else
 144 #  if !(@HAVE_PTHREAD_SIGMASK@ || defined pthread_sigmask)
 145 _GL_FUNCDECL_SYS (pthread_sigmask, int,
 146                   (int how,
 147                    const sigset_t *restrict new_mask,
 148                    sigset_t *restrict old_mask));
 149 #  endif
 150 _GL_CXXALIAS_SYS (pthread_sigmask, int,
 151                   (int how,
 152                    const sigset_t *restrict new_mask,
 153                    sigset_t *restrict old_mask));
 154 # endif
 155 # if __GLIBC__ >= 2
 156 _GL_CXXALIASWARN (pthread_sigmask);
 157 # endif
 158 #elif defined GNULIB_POSIXCHECK
 159 # undef pthread_sigmask
 160 # if HAVE_RAW_DECL_PTHREAD_SIGMASK
 161 _GL_WARN_ON_USE (pthread_sigmask, "pthread_sigmask is not portable - "
 162                  "use gnulib module pthread_sigmask for portability");
 163 # endif
 164 #endif
 165
 166
 167 #if @GNULIB_RAISE@
 168 # if @REPLACE_RAISE@
 169 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 170 #   undef raise
 171 #   define raise rpl_raise
 172 #  endif
 173 _GL_FUNCDECL_RPL (raise, int, (int sig));
 174 _GL_CXXALIAS_RPL (raise, int, (int sig));
 175 # else
 176 #  if !@HAVE_RAISE@
 177 _GL_FUNCDECL_SYS (raise, int, (int sig));
 178 #  endif
 179 _GL_CXXALIAS_SYS (raise, int, (int sig));
 180 # endif
 181 # if __GLIBC__ >= 2
 182 _GL_CXXALIASWARN (raise);
 183 # endif
 184 #elif defined GNULIB_POSIXCHECK
 185 # undef raise
 186 /* Assume raise is always declared.  */
 187 _GL_WARN_ON_USE (raise, "raise can crash on native Windows - "
 188                  "use gnulib module raise for portability");
 189 #endif
 190
 191
 192 #if @GNULIB_SIGPROCMASK@
 193 # if !@HAVE_POSIX_SIGNALBLOCKING@
 194
 195 #  ifndef GNULIB_defined_signal_blocking
 196 #   define GNULIB_defined_signal_blocking 1
 197 #  endif
 198
 199 /* Maximum signal number + 1.  */
 200 #  ifndef NSIG
 201 #   define NSIG 32
 202 #  endif
 203
 204 /* This code supports only 32 signals.  */
 205 #  if !GNULIB_defined_verify_NSIG_constraint
 206 typedef int verify_NSIG_constraint[NSIG <= 32 ? 1 : -1];
 207 #   define GNULIB_defined_verify_NSIG_constraint 1
 208 #  endif
 209
 210 # endif
 211
 212 /* When also using extern inline, suppress the use of static inline in
 213    standard headers of problematic Apple configurations, as Libc at
 214    least through Libc-825.26 (2013-04-09) mishandles it; see, e.g.,
 215    <https://lists.gnu.org/r/bug-gnulib/2012-12/msg00023.html>.
 216    Perhaps Apple will fix this some day.  */
 217 #if (defined _GL_EXTERN_INLINE_IN_USE && defined __APPLE__ \
 218      && (defined __i386__ || defined __x86_64__))
 219 # undef sigaddset
 220 # undef sigdelset
 221 # undef sigemptyset
 222 # undef sigfillset
 223 # undef sigismember
 224 #endif
 225
 226 /* Test whether a given signal is contained in a signal set.  */
 227 # if @HAVE_POSIX_SIGNALBLOCKING@
 228 /* This function is defined as a macro on Mac OS X.  */
 229 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 230 #   undef sigismember
 231 #  endif
 232 # else
 233 _GL_FUNCDECL_SYS (sigismember, int, (const sigset_t *set, int sig)
 234                                     _GL_ARG_NONNULL ((1)));
 235 # endif
 236 _GL_CXXALIAS_SYS (sigismember, int, (const sigset_t *set, int sig));
 237 _GL_CXXALIASWARN (sigismember);
 238
 239 /* Initialize a signal set to the empty set.  */
 240 # if @HAVE_POSIX_SIGNALBLOCKING@
 241 /* This function is defined as a macro on Mac OS X.  */
 242 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 243 #   undef sigemptyset
 244 #  endif
 245 # else
 246 _GL_FUNCDECL_SYS (sigemptyset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 247 # endif
 248 _GL_CXXALIAS_SYS (sigemptyset, int, (sigset_t *set));
 249 _GL_CXXALIASWARN (sigemptyset);
 250
 251 /* Add a signal to a signal set.  */
 252 # if @HAVE_POSIX_SIGNALBLOCKING@
 253 /* This function is defined as a macro on Mac OS X.  */
 254 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 255 #   undef sigaddset
 256 #  endif
 257 # else
 258 _GL_FUNCDECL_SYS (sigaddset, int, (sigset_t *set, int sig)
 259                                   _GL_ARG_NONNULL ((1)));
 260 # endif
 261 _GL_CXXALIAS_SYS (sigaddset, int, (sigset_t *set, int sig));
 262 _GL_CXXALIASWARN (sigaddset);
 263
 264 /* Remove a signal from a signal set.  */
 265 # if @HAVE_POSIX_SIGNALBLOCKING@
 266 /* This function is defined as a macro on Mac OS X.  */
 267 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 268 #   undef sigdelset
 269 #  endif
 270 # else
 271 _GL_FUNCDECL_SYS (sigdelset, int, (sigset_t *set, int sig)
 272                                   _GL_ARG_NONNULL ((1)));
 273 # endif
 274 _GL_CXXALIAS_SYS (sigdelset, int, (sigset_t *set, int sig));
 275 _GL_CXXALIASWARN (sigdelset);
 276
 277 /* Fill a signal set with all possible signals.  */
 278 # if @HAVE_POSIX_SIGNALBLOCKING@
 279 /* This function is defined as a macro on Mac OS X.  */
 280 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 281 #   undef sigfillset
 282 #  endif
 283 # else
 284 _GL_FUNCDECL_SYS (sigfillset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 285 # endif
 286 _GL_CXXALIAS_SYS (sigfillset, int, (sigset_t *set));
 287 _GL_CXXALIASWARN (sigfillset);
 288
 289 /* Return the set of those blocked signals that are pending.  */
 290 # if !@HAVE_POSIX_SIGNALBLOCKING@
 291 _GL_FUNCDECL_SYS (sigpending, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 292 # endif
 293 _GL_CXXALIAS_SYS (sigpending, int, (sigset_t *set));
 294 _GL_CXXALIASWARN (sigpending);
 295
 296 /* If OLD_SET is not NULL, put the current set of blocked signals in *OLD_SET.
 297    Then, if SET is not NULL, affect the current set of blocked signals by
 298    combining it with *SET as indicated in OPERATION.
 299    In this implementation, you are not allowed to change a signal handler
 300    while the signal is blocked.  */
 301 # if !@HAVE_POSIX_SIGNALBLOCKING@
 302 #  define SIG_BLOCK   0  /* blocked_set = blocked_set | *set; */
 303 #  define SIG_SETMASK 1  /* blocked_set = *set; */
 304 #  define SIG_UNBLOCK 2  /* blocked_set = blocked_set & ~*set; */
 305 _GL_FUNCDECL_SYS (sigprocmask, int,
 306                   (int operation,
 307                    const sigset_t *restrict set,
 308                    sigset_t *restrict old_set));
 309 # endif
 310 _GL_CXXALIAS_SYS (sigprocmask, int,
 311                   (int operation,
 312                    const sigset_t *restrict set,
 313                    sigset_t *restrict old_set));
 314 _GL_CXXALIASWARN (sigprocmask);
 315
 316 /* Install the handler FUNC for signal SIG, and return the previous
 317    handler.  */
 318 # ifdef __cplusplus
 319 extern "C" {
 320 # endif
 321 # if !GNULIB_defined_function_taking_int_returning_void_t
 322 typedef void (*_gl_function_taking_int_returning_void_t) (int);
 323 #  define GNULIB_defined_function_taking_int_returning_void_t 1
 324 # endif
 325 # ifdef __cplusplus
 326 }
 327 # endif
 328 # if !@HAVE_POSIX_SIGNALBLOCKING@
 329 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 330 #   define signal rpl_signal
 331 #  endif
 332 _GL_FUNCDECL_RPL (signal, _gl_function_taking_int_returning_void_t,
 333                   (int sig, _gl_function_taking_int_returning_void_t func));
 334 _GL_CXXALIAS_RPL (signal, _gl_function_taking_int_returning_void_t,
 335                   (int sig, _gl_function_taking_int_returning_void_t func));
 336 # else
 337 /* On OpenBSD, the declaration of 'signal' may not be present at this point,
 338    because it occurs in <sys/signal.h>, not <signal.h> directly.  */
 339 #  if defined __OpenBSD__
 340 _GL_FUNCDECL_SYS (signal, _gl_function_taking_int_returning_void_t,
 341                   (int sig, _gl_function_taking_int_returning_void_t func));
 342 #  endif
 343 _GL_CXXALIAS_SYS (signal, _gl_function_taking_int_returning_void_t,
 344                   (int sig, _gl_function_taking_int_returning_void_t func));
 345 # endif
 346 # if __GLIBC__ >= 2
 347 _GL_CXXALIASWARN (signal);
 348 # endif
 349
 350 # if !@HAVE_POSIX_SIGNALBLOCKING@ && GNULIB_defined_SIGPIPE
 351 /* Raise signal SIGPIPE.  */
 352 _GL_EXTERN_C int _gl_raise_SIGPIPE (void);
 353 # endif
 354
 355 #elif defined GNULIB_POSIXCHECK
 356 # undef sigaddset
 357 # if HAVE_RAW_DECL_SIGADDSET
 358 _GL_WARN_ON_USE (sigaddset, "sigaddset is unportable - "
 359                  "use the gnulib module sigprocmask for portability");
 360 # endif
 361 # undef sigdelset
 362 # if HAVE_RAW_DECL_SIGDELSET
 363 _GL_WARN_ON_USE (sigdelset, "sigdelset is unportable - "
 364                  "use the gnulib module sigprocmask for portability");
 365 # endif
 366 # undef sigemptyset
 367 # if HAVE_RAW_DECL_SIGEMPTYSET
 368 _GL_WARN_ON_USE (sigemptyset, "sigemptyset is unportable - "
 369                  "use the gnulib module sigprocmask for portability");
 370 # endif
 371 # undef sigfillset
 372 # if HAVE_RAW_DECL_SIGFILLSET
 373 _GL_WARN_ON_USE (sigfillset, "sigfillset is unportable - "
 374                  "use the gnulib module sigprocmask for portability");
 375 # endif
 376 # undef sigismember
 377 # if HAVE_RAW_DECL_SIGISMEMBER
 378 _GL_WARN_ON_USE (sigismember, "sigismember is unportable - "
 379                  "use the gnulib module sigprocmask for portability");
 380 # endif
 381 # undef sigpending
 382 # if HAVE_RAW_DECL_SIGPENDING
 383 _GL_WARN_ON_USE (sigpending, "sigpending is unportable - "
 384                  "use the gnulib module sigprocmask for portability");
 385 # endif
 386 # undef sigprocmask
 387 # if HAVE_RAW_DECL_SIGPROCMASK
 388 _GL_WARN_ON_USE (sigprocmask, "sigprocmask is unportable - "
 389                  "use the gnulib module sigprocmask for portability");
 390 # endif
 391 #endif /* @GNULIB_SIGPROCMASK@ */
 392
 393
 394 #if @GNULIB_SIGACTION@
 395 # if !@HAVE_SIGACTION@
 396
 397 #  if !@HAVE_SIGINFO_T@
 398
 399 #   if !GNULIB_defined_siginfo_types
 400
 401 /* Present to allow compilation, but unsupported by gnulib.  */
 402 union sigval
 403 {
 404   int sival_int;
 405   void *sival_ptr;
 406 };
 407
 408 /* Present to allow compilation, but unsupported by gnulib.  */
 409 struct siginfo_t
 410 {
 411   int si_signo;
 412   int si_code;
 413   int si_errno;
 414   pid_t si_pid;
 415   uid_t si_uid;
 416   void *si_addr;
 417   int si_status;
 418   long si_band;
 419   union sigval si_value;
 420 };
 421 typedef struct siginfo_t siginfo_t;
 422
 423 #    define GNULIB_defined_siginfo_types 1
 424 #   endif
 425
 426 #  endif /* !@HAVE_SIGINFO_T@ */
 427
 428 /* We assume that platforms which lack the sigaction() function also lack
 429    the 'struct sigaction' type, and vice versa.  */
 430
 431 #  if !GNULIB_defined_struct_sigaction
 432
 433 struct sigaction
 434 {
 435   union
 436   {
 437     void (*_sa_handler) (int);
 438     /* Present to allow compilation, but unsupported by gnulib.  POSIX
 439        says that implementations may, but not must, make sa_sigaction
 440        overlap with sa_handler, but we know of no implementation where
 441        they do not overlap.  */
 442     void (*_sa_sigaction) (int, siginfo_t *, void *);
 443   } _sa_func;
 444   sigset_t sa_mask;
 445   /* Not all POSIX flags are supported.  */
 446   int sa_flags;
 447 };
 448 #   define sa_handler _sa_func._sa_handler
 449 #   define sa_sigaction _sa_func._sa_sigaction
 450 /* Unsupported flags are not present.  */
 451 #   define SA_RESETHAND 1
 452 #   define SA_NODEFER 2
 453 #   define SA_RESTART 4
 454
 455 #   define GNULIB_defined_struct_sigaction 1
 456 #  endif
 457
 458 _GL_FUNCDECL_SYS (sigaction, int, (int, const struct sigaction *restrict,
 459                                    struct sigaction *restrict));
 460
 461 # elif !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@
 462
 463 #  define sa_sigaction sa_handler
 464
 465 # endif /* !@HAVE_SIGACTION@, !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@ */
 466
 467 _GL_CXXALIAS_SYS (sigaction, int, (int, const struct sigaction *restrict,
 468                                    struct sigaction *restrict));
 469 _GL_CXXALIASWARN (sigaction);
 470
 471 #elif defined GNULIB_POSIXCHECK
 472 # undef sigaction
 473 # if HAVE_RAW_DECL_SIGACTION
 474 _GL_WARN_ON_USE (sigaction, "sigaction is unportable - "
 475                  "use the gnulib module sigaction for portability");
 476 # endif
 477 #endif
 478
 479 /* Some systems don't have SA_NODEFER.  */
 480 #ifndef SA_NODEFER
 481 # define SA_NODEFER 0
 482 #endif
 483
 484
 485 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
 486 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
 487 #endif