lib/signal.in.h

   1 /* A GNU-like <signal.h>.
   2
   3    Copyright (C) 2006-2024 Free Software Foundation, Inc.
   4
   5    This file is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    License, or (at your option) any later version.
   9
  10    This file 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 Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser 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 /* This file uses GNULIB_POSIXCHECK, HAVE_RAW_DECL_*.  */
  59 #if !_GL_CONFIG_H_INCLUDED
  60  #error "Please include config.h first."
  61 #endif
  62
  63 /* For testing the OpenBSD version.  */
  64 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
  65     && defined __OpenBSD__
  66 # include <sys/param.h>
  67 #endif
  68
  69 /* Mac OS X 10.3, FreeBSD < 8.0, OpenBSD < 5.1, OSF/1 4.0, Solaris 2.6, Android,
  70    OS/2 kLIBC declare pthread_sigmask in <pthread.h>, not in <signal.h>.
  71    But avoid namespace pollution on glibc systems.*/
  72 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
  73     && ((defined __APPLE__ && defined __MACH__) \
  74         || (defined __FreeBSD__ && __FreeBSD__ < 8) \
  75         || (defined __OpenBSD__ && OpenBSD < 201205) \
  76         || defined __osf__ || defined __sun || defined __ANDROID__ \
  77         || defined __KLIBC__) \
  78     && ! defined __GLIBC__
  79 # include <pthread.h>
  80 #endif
  81
  82 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
  83
  84 /* The definition of _GL_ARG_NONNULL is copied here.  */
  85
  86 /* The definition of _GL_WARN_ON_USE is copied here.  */
  87
  88 /* On AIX, sig_atomic_t already includes volatile.  C99 requires that
  89    'volatile sig_atomic_t' ignore the extra modifier, but C89 did not.
  90    Hence, redefine this to a non-volatile type as needed.  */
  91 #if ! @HAVE_TYPE_VOLATILE_SIG_ATOMIC_T@
  92 # if !GNULIB_defined_sig_atomic_t
  93 typedef int rpl_sig_atomic_t;
  94 #  undef sig_atomic_t
  95 #  define sig_atomic_t rpl_sig_atomic_t
  96 #  define GNULIB_defined_sig_atomic_t 1
  97 # endif
  98 #endif
  99
 100 /* A set or mask of signals.  */
 101 #if !@HAVE_SIGSET_T@
 102 # if !GNULIB_defined_sigset_t
 103 typedef unsigned int sigset_t;
 104 #  define GNULIB_defined_sigset_t 1
 105 # endif
 106 #endif
 107
 108 /* Define sighandler_t, the type of signal handlers.  A GNU extension.  */
 109 #if !@HAVE_SIGHANDLER_T@
 110 # ifdef __cplusplus
 111 extern "C" {
 112 # endif
 113 # if !GNULIB_defined_sighandler_t
 114 typedef void (*sighandler_t) (int);
 115 #  define GNULIB_defined_sighandler_t 1
 116 # endif
 117 # ifdef __cplusplus
 118 }
 119 # endif
 120 #endif
 121
 122
 123 #if @GNULIB_SIGNAL_H_SIGPIPE@
 124 # ifndef SIGPIPE
 125 /* Define SIGPIPE to a value that does not overlap with other signals.  */
 126 #  define SIGPIPE 13
 127 #  define GNULIB_defined_SIGPIPE 1
 128 /* To actually use SIGPIPE, you also need the gnulib modules 'sigprocmask',
 129    'write', 'stdio'.  */
 130 # endif
 131 #endif
 132
 133
 134 /* Maximum signal number + 1.  */
 135 #ifndef NSIG
 136 # if defined __TANDEM
 137 #  define NSIG 32
 138 # endif
 139 #endif
 140
 141
 142 #if @GNULIB_PTHREAD_SIGMASK@
 143 # if @REPLACE_PTHREAD_SIGMASK@
 144 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 145 #   undef pthread_sigmask
 146 #   define pthread_sigmask rpl_pthread_sigmask
 147 #  endif
 148 _GL_FUNCDECL_RPL (pthread_sigmask, int,
 149                   (int how,
 150                    const sigset_t *restrict new_mask,
 151                    sigset_t *restrict old_mask));
 152 _GL_CXXALIAS_RPL (pthread_sigmask, int,
 153                   (int how,
 154                    const sigset_t *restrict new_mask,
 155                    sigset_t *restrict old_mask));
 156 # else
 157 #  if !(@HAVE_PTHREAD_SIGMASK@ || defined pthread_sigmask)
 158 _GL_FUNCDECL_SYS (pthread_sigmask, int,
 159                   (int how,
 160                    const sigset_t *restrict new_mask,
 161                    sigset_t *restrict old_mask));
 162 #  endif
 163 _GL_CXXALIAS_SYS (pthread_sigmask, int,
 164                   (int how,
 165                    const sigset_t *restrict new_mask,
 166                    sigset_t *restrict old_mask));
 167 # endif
 168 # if __GLIBC__ >= 2
 169 _GL_CXXALIASWARN (pthread_sigmask);
 170 # endif
 171 #elif defined GNULIB_POSIXCHECK
 172 # undef pthread_sigmask
 173 # if HAVE_RAW_DECL_PTHREAD_SIGMASK
 174 _GL_WARN_ON_USE (pthread_sigmask, "pthread_sigmask is not portable - "
 175                  "use gnulib module pthread_sigmask for portability");
 176 # endif
 177 #endif
 178
 179
 180 #if @GNULIB_RAISE@
 181 # if @REPLACE_RAISE@
 182 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 183 #   undef raise
 184 #   define raise rpl_raise
 185 #  endif
 186 _GL_FUNCDECL_RPL (raise, int, (int sig));
 187 _GL_CXXALIAS_RPL (raise, int, (int sig));
 188 # else
 189 #  if !@HAVE_RAISE@
 190 _GL_FUNCDECL_SYS (raise, int, (int sig));
 191 #  endif
 192 _GL_CXXALIAS_SYS (raise, int, (int sig));
 193 # endif
 194 # if __GLIBC__ >= 2
 195 _GL_CXXALIASWARN (raise);
 196 # endif
 197 #elif defined GNULIB_POSIXCHECK
 198 # undef raise
 199 /* Assume raise is always declared.  */
 200 _GL_WARN_ON_USE (raise, "raise can crash on native Windows - "
 201                  "use gnulib module raise for portability");
 202 #endif
 203
 204
 205 #if @GNULIB_SIGPROCMASK@
 206 # if !@HAVE_POSIX_SIGNALBLOCKING@
 207
 208 #  ifndef GNULIB_defined_signal_blocking
 209 #   define GNULIB_defined_signal_blocking 1
 210 #  endif
 211
 212 /* Maximum signal number + 1.  */
 213 #  ifndef NSIG
 214 #   define NSIG 32
 215 #  endif
 216
 217 /* This code supports only 32 signals.  */
 218 #  if !GNULIB_defined_verify_NSIG_constraint
 219 typedef int verify_NSIG_constraint[NSIG <= 32 ? 1 : -1];
 220 #   define GNULIB_defined_verify_NSIG_constraint 1
 221 #  endif
 222
 223 # endif
 224
 225 /* When also using extern inline, suppress the use of static inline in
 226    standard headers of problematic Apple configurations, as Libc at
 227    least through Libc-825.26 (2013-04-09) mishandles it; see, e.g.,
 228    <https://lists.gnu.org/r/bug-gnulib/2012-12/msg00023.html>.
 229    Perhaps Apple will fix this some day.  */
 230 #if (defined _GL_EXTERN_INLINE_IN_USE && defined __APPLE__ \
 231      && (defined __i386__ || defined __x86_64__))
 232 # undef sigaddset
 233 # undef sigdelset
 234 # undef sigemptyset
 235 # undef sigfillset
 236 # undef sigismember
 237 #endif
 238
 239 /* Test whether a given signal is contained in a signal 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 sigismember
 244 #  endif
 245 # else
 246 _GL_FUNCDECL_SYS (sigismember, int, (const sigset_t *set, int sig)
 247                                     _GL_ARG_NONNULL ((1)));
 248 # endif
 249 _GL_CXXALIAS_SYS (sigismember, int, (const sigset_t *set, int sig));
 250 _GL_CXXALIASWARN (sigismember);
 251
 252 /* Initialize a signal set to the empty set.  */
 253 # if @HAVE_POSIX_SIGNALBLOCKING@
 254 /* This function is defined as a macro on Mac OS X.  */
 255 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 256 #   undef sigemptyset
 257 #  endif
 258 # else
 259 _GL_FUNCDECL_SYS (sigemptyset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 260 # endif
 261 _GL_CXXALIAS_SYS (sigemptyset, int, (sigset_t *set));
 262 _GL_CXXALIASWARN (sigemptyset);
 263
 264 /* Add a signal to 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 sigaddset
 269 #  endif
 270 # else
 271 _GL_FUNCDECL_SYS (sigaddset, int, (sigset_t *set, int sig)
 272                                   _GL_ARG_NONNULL ((1)));
 273 # endif
 274 _GL_CXXALIAS_SYS (sigaddset, int, (sigset_t *set, int sig));
 275 _GL_CXXALIASWARN (sigaddset);
 276
 277 /* Remove a signal from a signal set.  */
 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 sigdelset
 282 #  endif
 283 # else
 284 _GL_FUNCDECL_SYS (sigdelset, int, (sigset_t *set, int sig)
 285                                   _GL_ARG_NONNULL ((1)));
 286 # endif
 287 _GL_CXXALIAS_SYS (sigdelset, int, (sigset_t *set, int sig));
 288 _GL_CXXALIASWARN (sigdelset);
 289
 290 /* Fill a signal set with all possible signals.  */
 291 # if @HAVE_POSIX_SIGNALBLOCKING@
 292 /* This function is defined as a macro on Mac OS X.  */
 293 #  if defined __cplusplus && defined GNULIB_NAMESPACE
 294 #   undef sigfillset
 295 #  endif
 296 # else
 297 _GL_FUNCDECL_SYS (sigfillset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 298 # endif
 299 _GL_CXXALIAS_SYS (sigfillset, int, (sigset_t *set));
 300 _GL_CXXALIASWARN (sigfillset);
 301
 302 /* Return the set of those blocked signals that are pending.  */
 303 # if !@HAVE_POSIX_SIGNALBLOCKING@
 304 _GL_FUNCDECL_SYS (sigpending, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
 305 # endif
 306 _GL_CXXALIAS_SYS (sigpending, int, (sigset_t *set));
 307 _GL_CXXALIASWARN (sigpending);
 308
 309 /* If OLD_SET is not NULL, put the current set of blocked signals in *OLD_SET.
 310    Then, if SET is not NULL, affect the current set of blocked signals by
 311    combining it with *SET as indicated in OPERATION.
 312    In this implementation, you are not allowed to change a signal handler
 313    while the signal is blocked.  */
 314 # if !@HAVE_POSIX_SIGNALBLOCKING@
 315 #  define SIG_BLOCK   0  /* blocked_set = blocked_set | *set; */
 316 #  define SIG_SETMASK 1  /* blocked_set = *set; */
 317 #  define SIG_UNBLOCK 2  /* blocked_set = blocked_set & ~*set; */
 318 _GL_FUNCDECL_SYS (sigprocmask, int,
 319                   (int operation,
 320                    const sigset_t *restrict set,
 321                    sigset_t *restrict old_set));
 322 # endif
 323 _GL_CXXALIAS_SYS (sigprocmask, int,
 324                   (int operation,
 325                    const sigset_t *restrict set,
 326                    sigset_t *restrict old_set));
 327 _GL_CXXALIASWARN (sigprocmask);
 328
 329 /* Install the handler FUNC for signal SIG, and return the previous
 330    handler.  */
 331 # ifdef __cplusplus
 332 extern "C" {
 333 # endif
 334 # if !GNULIB_defined_function_taking_int_returning_void_t
 335 typedef void (*_gl_function_taking_int_returning_void_t) (int);
 336 #  define GNULIB_defined_function_taking_int_returning_void_t 1
 337 # endif
 338 # ifdef __cplusplus
 339 }
 340 # endif
 341 # if !@HAVE_POSIX_SIGNALBLOCKING@
 342 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
 343 #   define signal rpl_signal
 344 #  endif
 345 _GL_FUNCDECL_RPL (signal, _gl_function_taking_int_returning_void_t,
 346                   (int sig, _gl_function_taking_int_returning_void_t func));
 347 _GL_CXXALIAS_RPL (signal, _gl_function_taking_int_returning_void_t,
 348                   (int sig, _gl_function_taking_int_returning_void_t func));
 349 # else
 350 /* On OpenBSD, the declaration of 'signal' may not be present at this point,
 351    because it occurs in <sys/signal.h>, not <signal.h> directly.  */
 352 #  if defined __OpenBSD__
 353 _GL_FUNCDECL_SYS (signal, _gl_function_taking_int_returning_void_t,
 354                   (int sig, _gl_function_taking_int_returning_void_t func));
 355 #  endif
 356 _GL_CXXALIAS_SYS (signal, _gl_function_taking_int_returning_void_t,
 357                   (int sig, _gl_function_taking_int_returning_void_t func));
 358 # endif
 359 # if __GLIBC__ >= 2
 360 _GL_CXXALIASWARN (signal);
 361 # endif
 362
 363 # if !@HAVE_POSIX_SIGNALBLOCKING@ && GNULIB_defined_SIGPIPE
 364 /* Raise signal SIGPIPE.  */
 365 _GL_EXTERN_C int _gl_raise_SIGPIPE (void);
 366 # endif
 367
 368 #elif defined GNULIB_POSIXCHECK
 369 # undef sigaddset
 370 # if HAVE_RAW_DECL_SIGADDSET
 371 _GL_WARN_ON_USE (sigaddset, "sigaddset is unportable - "
 372                  "use the gnulib module sigprocmask for portability");
 373 # endif
 374 # undef sigdelset
 375 # if HAVE_RAW_DECL_SIGDELSET
 376 _GL_WARN_ON_USE (sigdelset, "sigdelset is unportable - "
 377                  "use the gnulib module sigprocmask for portability");
 378 # endif
 379 # undef sigemptyset
 380 # if HAVE_RAW_DECL_SIGEMPTYSET
 381 _GL_WARN_ON_USE (sigemptyset, "sigemptyset is unportable - "
 382                  "use the gnulib module sigprocmask for portability");
 383 # endif
 384 # undef sigfillset
 385 # if HAVE_RAW_DECL_SIGFILLSET
 386 _GL_WARN_ON_USE (sigfillset, "sigfillset is unportable - "
 387                  "use the gnulib module sigprocmask for portability");
 388 # endif
 389 # undef sigismember
 390 # if HAVE_RAW_DECL_SIGISMEMBER
 391 _GL_WARN_ON_USE (sigismember, "sigismember is unportable - "
 392                  "use the gnulib module sigprocmask for portability");
 393 # endif
 394 # undef sigpending
 395 # if HAVE_RAW_DECL_SIGPENDING
 396 _GL_WARN_ON_USE (sigpending, "sigpending is unportable - "
 397                  "use the gnulib module sigprocmask for portability");
 398 # endif
 399 # undef sigprocmask
 400 # if HAVE_RAW_DECL_SIGPROCMASK
 401 _GL_WARN_ON_USE (sigprocmask, "sigprocmask is unportable - "
 402                  "use the gnulib module sigprocmask for portability");
 403 # endif
 404 #endif /* @GNULIB_SIGPROCMASK@ */
 405
 406
 407 #if @GNULIB_SIGACTION@
 408 # if !@HAVE_SIGACTION@
 409
 410 #  if !@HAVE_SIGINFO_T@
 411
 412 #   if !GNULIB_defined_siginfo_types
 413
 414 /* Present to allow compilation, but unsupported by gnulib.  */
 415 union sigval
 416 {
 417   int sival_int;
 418   void *sival_ptr;
 419 };
 420
 421 /* Present to allow compilation, but unsupported by gnulib.  */
 422 struct siginfo_t
 423 {
 424   int si_signo;
 425   int si_code;
 426   int si_errno;
 427   pid_t si_pid;
 428   uid_t si_uid;
 429   void *si_addr;
 430   int si_status;
 431   long si_band;
 432   union sigval si_value;
 433 };
 434 typedef struct siginfo_t siginfo_t;
 435
 436 #    define GNULIB_defined_siginfo_types 1
 437 #   endif
 438
 439 #  endif /* !@HAVE_SIGINFO_T@ */
 440
 441 /* We assume that platforms which lack the sigaction() function also lack
 442    the 'struct sigaction' type, and vice versa.  */
 443
 444 #  if !GNULIB_defined_struct_sigaction
 445
 446 struct sigaction
 447 {
 448   union
 449   {
 450     void (*_sa_handler) (int);
 451     /* Present to allow compilation, but unsupported by gnulib.  POSIX
 452        says that implementations may, but not must, make sa_sigaction
 453        overlap with sa_handler, but we know of no implementation where
 454        they do not overlap.  */
 455     void (*_sa_sigaction) (int, siginfo_t *, void *);
 456   } _sa_func;
 457   sigset_t sa_mask;
 458   /* Not all POSIX flags are supported.  */
 459   int sa_flags;
 460 };
 461 #   define sa_handler _sa_func._sa_handler
 462 #   define sa_sigaction _sa_func._sa_sigaction
 463 /* Unsupported flags are not present.  */
 464 #   define SA_RESETHAND 1
 465 #   define SA_NODEFER 2
 466 #   define SA_RESTART 4
 467
 468 #   define GNULIB_defined_struct_sigaction 1
 469 #  endif
 470
 471 _GL_FUNCDECL_SYS (sigaction, int, (int, const struct sigaction *restrict,
 472                                    struct sigaction *restrict));
 473
 474 # elif !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@
 475
 476 #  define sa_sigaction sa_handler
 477
 478 # endif /* !@HAVE_SIGACTION@, !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@ */
 479
 480 _GL_CXXALIAS_SYS (sigaction, int, (int, const struct sigaction *restrict,
 481                                    struct sigaction *restrict));
 482 _GL_CXXALIASWARN (sigaction);
 483
 484 #elif defined GNULIB_POSIXCHECK
 485 # undef sigaction
 486 # if HAVE_RAW_DECL_SIGACTION
 487 _GL_WARN_ON_USE (sigaction, "sigaction is unportable - "
 488                  "use the gnulib module sigaction for portability");
 489 # endif
 490 #endif
 491
 492 /* Some systems don't have SA_NODEFER.  */
 493 #ifndef SA_NODEFER
 494 # define SA_NODEFER 0
 495 #endif
 496
 497
 498 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
 499 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
 500 #endif