root/lib/signal.in.h

     1 /* A GNU-like <signal.h>.
     2 
     3    Copyright (C) 2006-2023 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 /* For testing the OpenBSD version.  */
    59 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
    60     && defined __OpenBSD__
    61 # include <sys/param.h>
    62 #endif
    63 
    64 /* Mac OS X 10.3, FreeBSD < 8.0, OpenBSD < 5.1, OSF/1 4.0, Solaris 2.6, Android,
    65    OS/2 kLIBC declare pthread_sigmask in <pthread.h>, not in <signal.h>.
    66    But avoid namespace pollution on glibc systems.*/
    67 #if (@GNULIB_PTHREAD_SIGMASK@ || defined GNULIB_POSIXCHECK) \
    68     && ((defined __APPLE__ && defined __MACH__) \
    69         || (defined __FreeBSD__ && __FreeBSD__ < 8) \
    70         || (defined __OpenBSD__ && OpenBSD < 201205) \
    71         || defined __osf__ || defined __sun || defined __ANDROID__ \
    72         || defined __KLIBC__) \
    73     && ! defined __GLIBC__
    74 # include <pthread.h>
    75 #endif
    76 
    77 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
    78 
    79 /* The definition of _GL_ARG_NONNULL is copied here.  */
    80 
    81 /* The definition of _GL_WARN_ON_USE is copied here.  */
    82 
    83 /* On AIX, sig_atomic_t already includes volatile.  C99 requires that
    84    'volatile sig_atomic_t' ignore the extra modifier, but C89 did not.
    85    Hence, redefine this to a non-volatile type as needed.  */
    86 #if ! @HAVE_TYPE_VOLATILE_SIG_ATOMIC_T@
    87 # if !GNULIB_defined_sig_atomic_t
    88 typedef int rpl_sig_atomic_t;
    89 #  undef sig_atomic_t
    90 #  define sig_atomic_t rpl_sig_atomic_t
    91 #  define GNULIB_defined_sig_atomic_t 1
    92 # endif
    93 #endif
    94 
    95 /* A set or mask of signals.  */
    96 #if !@HAVE_SIGSET_T@
    97 # if !GNULIB_defined_sigset_t
    98 typedef unsigned int sigset_t;
    99 #  define GNULIB_defined_sigset_t 1
   100 # endif
   101 #endif
   102 
   103 /* Define sighandler_t, the type of signal handlers.  A GNU extension.  */
   104 #if !@HAVE_SIGHANDLER_T@
   105 # ifdef __cplusplus
   106 extern "C" {
   107 # endif
   108 # if !GNULIB_defined_sighandler_t
   109 typedef void (*sighandler_t) (int);
   110 #  define GNULIB_defined_sighandler_t 1
   111 # endif
   112 # ifdef __cplusplus
   113 }
   114 # endif
   115 #endif
   116 
   117 
   118 #if @GNULIB_SIGNAL_H_SIGPIPE@
   119 # ifndef SIGPIPE
   120 /* Define SIGPIPE to a value that does not overlap with other signals.  */
   121 #  define SIGPIPE 13
   122 #  define GNULIB_defined_SIGPIPE 1
   123 /* To actually use SIGPIPE, you also need the gnulib modules 'sigprocmask',
   124    'write', 'stdio'.  */
   125 # endif
   126 #endif
   127 
   128 
   129 /* Maximum signal number + 1.  */
   130 #ifndef NSIG
   131 # if defined __TANDEM
   132 #  define NSIG 32
   133 # endif
   134 #endif
   135 
   136 
   137 #if @GNULIB_PTHREAD_SIGMASK@
   138 # if @REPLACE_PTHREAD_SIGMASK@
   139 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
   140 #   undef pthread_sigmask
   141 #   define pthread_sigmask rpl_pthread_sigmask
   142 #  endif
   143 _GL_FUNCDECL_RPL (pthread_sigmask, int,
   144                   (int how,
   145                    const sigset_t *restrict new_mask,
   146                    sigset_t *restrict old_mask));
   147 _GL_CXXALIAS_RPL (pthread_sigmask, int,
   148                   (int how,
   149                    const sigset_t *restrict new_mask,
   150                    sigset_t *restrict old_mask));
   151 # else
   152 #  if !(@HAVE_PTHREAD_SIGMASK@ || defined pthread_sigmask)
   153 _GL_FUNCDECL_SYS (pthread_sigmask, int,
   154                   (int how,
   155                    const sigset_t *restrict new_mask,
   156                    sigset_t *restrict old_mask));
   157 #  endif
   158 _GL_CXXALIAS_SYS (pthread_sigmask, int,
   159                   (int how,
   160                    const sigset_t *restrict new_mask,
   161                    sigset_t *restrict old_mask));
   162 # endif
   163 # if __GLIBC__ >= 2
   164 _GL_CXXALIASWARN (pthread_sigmask);
   165 # endif
   166 #elif defined GNULIB_POSIXCHECK
   167 # undef pthread_sigmask
   168 # if HAVE_RAW_DECL_PTHREAD_SIGMASK
   169 _GL_WARN_ON_USE (pthread_sigmask, "pthread_sigmask is not portable - "
   170                  "use gnulib module pthread_sigmask for portability");
   171 # endif
   172 #endif
   173 
   174 
   175 #if @GNULIB_RAISE@
   176 # if @REPLACE_RAISE@
   177 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
   178 #   undef raise
   179 #   define raise rpl_raise
   180 #  endif
   181 _GL_FUNCDECL_RPL (raise, int, (int sig));
   182 _GL_CXXALIAS_RPL (raise, int, (int sig));
   183 # else
   184 #  if !@HAVE_RAISE@
   185 _GL_FUNCDECL_SYS (raise, int, (int sig));
   186 #  endif
   187 _GL_CXXALIAS_SYS (raise, int, (int sig));
   188 # endif
   189 # if __GLIBC__ >= 2
   190 _GL_CXXALIASWARN (raise);
   191 # endif
   192 #elif defined GNULIB_POSIXCHECK
   193 # undef raise
   194 /* Assume raise is always declared.  */
   195 _GL_WARN_ON_USE (raise, "raise can crash on native Windows - "
   196                  "use gnulib module raise for portability");
   197 #endif
   198 
   199 
   200 #if @GNULIB_SIGPROCMASK@
   201 # if !@HAVE_POSIX_SIGNALBLOCKING@
   202 
   203 #  ifndef GNULIB_defined_signal_blocking
   204 #   define GNULIB_defined_signal_blocking 1
   205 #  endif
   206 
   207 /* Maximum signal number + 1.  */
   208 #  ifndef NSIG
   209 #   define NSIG 32
   210 #  endif
   211 
   212 /* This code supports only 32 signals.  */
   213 #  if !GNULIB_defined_verify_NSIG_constraint
   214 typedef int verify_NSIG_constraint[NSIG <= 32 ? 1 : -1];
   215 #   define GNULIB_defined_verify_NSIG_constraint 1
   216 #  endif
   217 
   218 # endif
   219 
   220 /* When also using extern inline, suppress the use of static inline in
   221    standard headers of problematic Apple configurations, as Libc at
   222    least through Libc-825.26 (2013-04-09) mishandles it; see, e.g.,
   223    <https://lists.gnu.org/r/bug-gnulib/2012-12/msg00023.html>.
   224    Perhaps Apple will fix this some day.  */
   225 #if (defined _GL_EXTERN_INLINE_IN_USE && defined __APPLE__ \
   226      && (defined __i386__ || defined __x86_64__))
   227 # undef sigaddset
   228 # undef sigdelset
   229 # undef sigemptyset
   230 # undef sigfillset
   231 # undef sigismember
   232 #endif
   233 
   234 /* Test whether a given signal is contained in a signal set.  */
   235 # if @HAVE_POSIX_SIGNALBLOCKING@
   236 /* This function is defined as a macro on Mac OS X.  */
   237 #  if defined __cplusplus && defined GNULIB_NAMESPACE
   238 #   undef sigismember
   239 #  endif
   240 # else
   241 _GL_FUNCDECL_SYS (sigismember, int, (const sigset_t *set, int sig)
   242                                     _GL_ARG_NONNULL ((1)));
   243 # endif
   244 _GL_CXXALIAS_SYS (sigismember, int, (const sigset_t *set, int sig));
   245 _GL_CXXALIASWARN (sigismember);
   246 
   247 /* Initialize a signal set to the empty set.  */
   248 # if @HAVE_POSIX_SIGNALBLOCKING@
   249 /* This function is defined as a macro on Mac OS X.  */
   250 #  if defined __cplusplus && defined GNULIB_NAMESPACE
   251 #   undef sigemptyset
   252 #  endif
   253 # else
   254 _GL_FUNCDECL_SYS (sigemptyset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
   255 # endif
   256 _GL_CXXALIAS_SYS (sigemptyset, int, (sigset_t *set));
   257 _GL_CXXALIASWARN (sigemptyset);
   258 
   259 /* Add a signal to a signal set.  */
   260 # if @HAVE_POSIX_SIGNALBLOCKING@
   261 /* This function is defined as a macro on Mac OS X.  */
   262 #  if defined __cplusplus && defined GNULIB_NAMESPACE
   263 #   undef sigaddset
   264 #  endif
   265 # else
   266 _GL_FUNCDECL_SYS (sigaddset, int, (sigset_t *set, int sig)
   267                                   _GL_ARG_NONNULL ((1)));
   268 # endif
   269 _GL_CXXALIAS_SYS (sigaddset, int, (sigset_t *set, int sig));
   270 _GL_CXXALIASWARN (sigaddset);
   271 
   272 /* Remove a signal from a signal set.  */
   273 # if @HAVE_POSIX_SIGNALBLOCKING@
   274 /* This function is defined as a macro on Mac OS X.  */
   275 #  if defined __cplusplus && defined GNULIB_NAMESPACE
   276 #   undef sigdelset
   277 #  endif
   278 # else
   279 _GL_FUNCDECL_SYS (sigdelset, int, (sigset_t *set, int sig)
   280                                   _GL_ARG_NONNULL ((1)));
   281 # endif
   282 _GL_CXXALIAS_SYS (sigdelset, int, (sigset_t *set, int sig));
   283 _GL_CXXALIASWARN (sigdelset);
   284 
   285 /* Fill a signal set with all possible signals.  */
   286 # if @HAVE_POSIX_SIGNALBLOCKING@
   287 /* This function is defined as a macro on Mac OS X.  */
   288 #  if defined __cplusplus && defined GNULIB_NAMESPACE
   289 #   undef sigfillset
   290 #  endif
   291 # else
   292 _GL_FUNCDECL_SYS (sigfillset, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
   293 # endif
   294 _GL_CXXALIAS_SYS (sigfillset, int, (sigset_t *set));
   295 _GL_CXXALIASWARN (sigfillset);
   296 
   297 /* Return the set of those blocked signals that are pending.  */
   298 # if !@HAVE_POSIX_SIGNALBLOCKING@
   299 _GL_FUNCDECL_SYS (sigpending, int, (sigset_t *set) _GL_ARG_NONNULL ((1)));
   300 # endif
   301 _GL_CXXALIAS_SYS (sigpending, int, (sigset_t *set));
   302 _GL_CXXALIASWARN (sigpending);
   303 
   304 /* If OLD_SET is not NULL, put the current set of blocked signals in *OLD_SET.
   305    Then, if SET is not NULL, affect the current set of blocked signals by
   306    combining it with *SET as indicated in OPERATION.
   307    In this implementation, you are not allowed to change a signal handler
   308    while the signal is blocked.  */
   309 # if !@HAVE_POSIX_SIGNALBLOCKING@
   310 #  define SIG_BLOCK   0  /* blocked_set = blocked_set | *set; */
   311 #  define SIG_SETMASK 1  /* blocked_set = *set; */
   312 #  define SIG_UNBLOCK 2  /* blocked_set = blocked_set & ~*set; */
   313 _GL_FUNCDECL_SYS (sigprocmask, int,
   314                   (int operation,
   315                    const sigset_t *restrict set,
   316                    sigset_t *restrict old_set));
   317 # endif
   318 _GL_CXXALIAS_SYS (sigprocmask, int,
   319                   (int operation,
   320                    const sigset_t *restrict set,
   321                    sigset_t *restrict old_set));
   322 _GL_CXXALIASWARN (sigprocmask);
   323 
   324 /* Install the handler FUNC for signal SIG, and return the previous
   325    handler.  */
   326 # ifdef __cplusplus
   327 extern "C" {
   328 # endif
   329 # if !GNULIB_defined_function_taking_int_returning_void_t
   330 typedef void (*_gl_function_taking_int_returning_void_t) (int);
   331 #  define GNULIB_defined_function_taking_int_returning_void_t 1
   332 # endif
   333 # ifdef __cplusplus
   334 }
   335 # endif
   336 # if !@HAVE_POSIX_SIGNALBLOCKING@
   337 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
   338 #   define signal rpl_signal
   339 #  endif
   340 _GL_FUNCDECL_RPL (signal, _gl_function_taking_int_returning_void_t,
   341                   (int sig, _gl_function_taking_int_returning_void_t func));
   342 _GL_CXXALIAS_RPL (signal, _gl_function_taking_int_returning_void_t,
   343                   (int sig, _gl_function_taking_int_returning_void_t func));
   344 # else
   345 /* On OpenBSD, the declaration of 'signal' may not be present at this point,
   346    because it occurs in <sys/signal.h>, not <signal.h> directly.  */
   347 #  if defined __OpenBSD__
   348 _GL_FUNCDECL_SYS (signal, _gl_function_taking_int_returning_void_t,
   349                   (int sig, _gl_function_taking_int_returning_void_t func));
   350 #  endif
   351 _GL_CXXALIAS_SYS (signal, _gl_function_taking_int_returning_void_t,
   352                   (int sig, _gl_function_taking_int_returning_void_t func));
   353 # endif
   354 # if __GLIBC__ >= 2
   355 _GL_CXXALIASWARN (signal);
   356 # endif
   357 
   358 # if !@HAVE_POSIX_SIGNALBLOCKING@ && GNULIB_defined_SIGPIPE
   359 /* Raise signal SIGPIPE.  */
   360 _GL_EXTERN_C int _gl_raise_SIGPIPE (void);
   361 # endif
   362 
   363 #elif defined GNULIB_POSIXCHECK
   364 # undef sigaddset
   365 # if HAVE_RAW_DECL_SIGADDSET
   366 _GL_WARN_ON_USE (sigaddset, "sigaddset is unportable - "
   367                  "use the gnulib module sigprocmask for portability");
   368 # endif
   369 # undef sigdelset
   370 # if HAVE_RAW_DECL_SIGDELSET
   371 _GL_WARN_ON_USE (sigdelset, "sigdelset is unportable - "
   372                  "use the gnulib module sigprocmask for portability");
   373 # endif
   374 # undef sigemptyset
   375 # if HAVE_RAW_DECL_SIGEMPTYSET
   376 _GL_WARN_ON_USE (sigemptyset, "sigemptyset is unportable - "
   377                  "use the gnulib module sigprocmask for portability");
   378 # endif
   379 # undef sigfillset
   380 # if HAVE_RAW_DECL_SIGFILLSET
   381 _GL_WARN_ON_USE (sigfillset, "sigfillset is unportable - "
   382                  "use the gnulib module sigprocmask for portability");
   383 # endif
   384 # undef sigismember
   385 # if HAVE_RAW_DECL_SIGISMEMBER
   386 _GL_WARN_ON_USE (sigismember, "sigismember is unportable - "
   387                  "use the gnulib module sigprocmask for portability");
   388 # endif
   389 # undef sigpending
   390 # if HAVE_RAW_DECL_SIGPENDING
   391 _GL_WARN_ON_USE (sigpending, "sigpending is unportable - "
   392                  "use the gnulib module sigprocmask for portability");
   393 # endif
   394 # undef sigprocmask
   395 # if HAVE_RAW_DECL_SIGPROCMASK
   396 _GL_WARN_ON_USE (sigprocmask, "sigprocmask is unportable - "
   397                  "use the gnulib module sigprocmask for portability");
   398 # endif
   399 #endif /* @GNULIB_SIGPROCMASK@ */
   400 
   401 
   402 #if @GNULIB_SIGACTION@
   403 # if !@HAVE_SIGACTION@
   404 
   405 #  if !@HAVE_SIGINFO_T@
   406 
   407 #   if !GNULIB_defined_siginfo_types
   408 
   409 /* Present to allow compilation, but unsupported by gnulib.  */
   410 union sigval
   411 {
   412   int sival_int;
   413   void *sival_ptr;
   414 };
   415 
   416 /* Present to allow compilation, but unsupported by gnulib.  */
   417 struct siginfo_t
   418 {
   419   int si_signo;
   420   int si_code;
   421   int si_errno;
   422   pid_t si_pid;
   423   uid_t si_uid;
   424   void *si_addr;
   425   int si_status;
   426   long si_band;
   427   union sigval si_value;
   428 };
   429 typedef struct siginfo_t siginfo_t;
   430 
   431 #    define GNULIB_defined_siginfo_types 1
   432 #   endif
   433 
   434 #  endif /* !@HAVE_SIGINFO_T@ */
   435 
   436 /* We assume that platforms which lack the sigaction() function also lack
   437    the 'struct sigaction' type, and vice versa.  */
   438 
   439 #  if !GNULIB_defined_struct_sigaction
   440 
   441 struct sigaction
   442 {
   443   union
   444   {
   445     void (*_sa_handler) (int);
   446     /* Present to allow compilation, but unsupported by gnulib.  POSIX
   447        says that implementations may, but not must, make sa_sigaction
   448        overlap with sa_handler, but we know of no implementation where
   449        they do not overlap.  */
   450     void (*_sa_sigaction) (int, siginfo_t *, void *);
   451   } _sa_func;
   452   sigset_t sa_mask;
   453   /* Not all POSIX flags are supported.  */
   454   int sa_flags;
   455 };
   456 #   define sa_handler _sa_func._sa_handler
   457 #   define sa_sigaction _sa_func._sa_sigaction
   458 /* Unsupported flags are not present.  */
   459 #   define SA_RESETHAND 1
   460 #   define SA_NODEFER 2
   461 #   define SA_RESTART 4
   462 
   463 #   define GNULIB_defined_struct_sigaction 1
   464 #  endif
   465 
   466 _GL_FUNCDECL_SYS (sigaction, int, (int, const struct sigaction *restrict,
   467                                    struct sigaction *restrict));
   468 
   469 # elif !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@
   470 
   471 #  define sa_sigaction sa_handler
   472 
   473 # endif /* !@HAVE_SIGACTION@, !@HAVE_STRUCT_SIGACTION_SA_SIGACTION@ */
   474 
   475 _GL_CXXALIAS_SYS (sigaction, int, (int, const struct sigaction *restrict,
   476                                    struct sigaction *restrict));
   477 _GL_CXXALIASWARN (sigaction);
   478 
   479 #elif defined GNULIB_POSIXCHECK
   480 # undef sigaction
   481 # if HAVE_RAW_DECL_SIGACTION
   482 _GL_WARN_ON_USE (sigaction, "sigaction is unportable - "
   483                  "use the gnulib module sigaction for portability");
   484 # endif
   485 #endif
   486 
   487 /* Some systems don't have SA_NODEFER.  */
   488 #ifndef SA_NODEFER
   489 # define SA_NODEFER 0
   490 #endif
   491 
   492 
   493 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
   494 #endif /* _@GUARD_PREFIX@_SIGNAL_H */
   495 #endif