3 dnl Copyright (C) 2007-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 AC_DEFUN_ONCE([gl_SIGNAL_H],
10 AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
11 AC_REQUIRE([gl_CHECK_TYPE_SIGSET_T])
12 gl_NEXT_HEADERS([signal.h])
14 # AIX declares sig_atomic_t to already include volatile, and C89 compilers
15 # then choke on 'volatile sig_atomic_t'. C99 requires that it compile.
16 AC_CHECK_TYPE([volatile sig_atomic_t], [],
17 [HAVE_TYPE_VOLATILE_SIG_ATOMIC_T=0], [[
21 dnl Ensure the type pid_t gets defined.
22 AC_REQUIRE([AC_TYPE_PID_T])
24 AC_REQUIRE([AC_TYPE_UID_T])
26 dnl Persuade glibc <signal.h> to define sighandler_t.
27 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
28 AC_CHECK_TYPE([sighandler_t], [], [HAVE_SIGHANDLER_T=0], [[
32 dnl Check for declarations of anything we want to poison if the
33 dnl corresponding gnulib module is not in use.
34 gl_WARN_ON_USE_PREPARE([[#include <signal.h>
35 ]], [pthread_sigmask sigaction
36 sigaddset sigdelset sigemptyset sigfillset sigismember
37 sigpending sigprocmask])
39 AC_REQUIRE([AC_C_RESTRICT])
42 AC_DEFUN([gl_CHECK_TYPE_SIGSET_T],
44 AC_CHECK_TYPES([sigset_t],
45 [gl_cv_type_sigset_t=yes], [gl_cv_type_sigset_t=no],
48 /* Mingw defines sigset_t not in <signal.h>, but in <sys/types.h>. */
49 #include <sys/types.h>
51 if test $gl_cv_type_sigset_t != yes; then
56 # gl_SIGNAL_MODULE_INDICATOR([modulename])
57 # sets the shell variable that indicates the presence of the given module
58 # to a C preprocessor expression that will evaluate to 1.
59 # This macro invocation must not occur in macros that are AC_REQUIREd.
60 AC_DEFUN([gl_SIGNAL_MODULE_INDICATOR],
62 dnl Ensure to expand the default settings once only.
63 gl_SIGNAL_H_REQUIRE_DEFAULTS
64 gl_MODULE_INDICATOR_SET_VARIABLE([$1])
65 dnl Define it also as a C macro, for the benefit of the unit tests.
66 gl_MODULE_INDICATOR_FOR_TESTS([$1])
69 # Initializes the default values for AC_SUBSTed shell variables.
70 # This macro must not be AC_REQUIREd. It must only be invoked, and only
71 # outside of macros or in macros that are not AC_REQUIREd.
72 AC_DEFUN([gl_SIGNAL_H_REQUIRE_DEFAULTS],
74 m4_defun(GL_MODULE_INDICATOR_PREFIX[_SIGNAL_H_MODULE_INDICATOR_DEFAULTS], [
75 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_PTHREAD_SIGMASK])
76 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_RAISE])
77 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_SIGNAL_H_SIGPIPE])
78 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_SIGPROCMASK])
79 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_SIGACTION])
81 m4_require(GL_MODULE_INDICATOR_PREFIX[_SIGNAL_H_MODULE_INDICATOR_DEFAULTS])
82 AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
85 AC_DEFUN([gl_SIGNAL_H_DEFAULTS],
87 dnl Assume proper GNU behavior unless another module says otherwise.
88 HAVE_POSIX_SIGNALBLOCKING=1; AC_SUBST([HAVE_POSIX_SIGNALBLOCKING])
89 HAVE_PTHREAD_SIGMASK=1; AC_SUBST([HAVE_PTHREAD_SIGMASK])
90 HAVE_RAISE=1; AC_SUBST([HAVE_RAISE])
91 HAVE_SIGSET_T=1; AC_SUBST([HAVE_SIGSET_T])
92 HAVE_SIGINFO_T=1; AC_SUBST([HAVE_SIGINFO_T])
93 HAVE_SIGACTION=1; AC_SUBST([HAVE_SIGACTION])
94 HAVE_STRUCT_SIGACTION_SA_SIGACTION=1;
95 AC_SUBST([HAVE_STRUCT_SIGACTION_SA_SIGACTION])
96 HAVE_TYPE_VOLATILE_SIG_ATOMIC_T=1;
97 AC_SUBST([HAVE_TYPE_VOLATILE_SIG_ATOMIC_T])
98 HAVE_SIGHANDLER_T=1; AC_SUBST([HAVE_SIGHANDLER_T])
99 REPLACE_PTHREAD_SIGMASK=0; AC_SUBST([REPLACE_PTHREAD_SIGMASK])
100 REPLACE_RAISE=0; AC_SUBST([REPLACE_RAISE])