Github/emacs
2
0
Fork 1
mirror of git://git.sv.gnu.org/emacs.git synced 2026-06-14 04:21:24 +00:00
Code Issues Projects Releases Packages Wiki Activity
emacs/m4/pthread_sigmask.m4
Paul Eggert 834ff524f9 Update from Gnulib by running admin/merge-gnulib 
In addition to the automatic changes, also do the following,
needed due to recent Gnulib changes.
* admin/merge-gnulib (AVOIDED_MODULES): Add btoc32,
c32_apply_type_test, c32_get_type_test, c32isalnum, c32rtomb,
c32tolower, c32toupper, localeinfo, mbrtoc32-regular.
Remove btowc, iswctype, mbrtowc, wcrtomb, wctype, wctype-h.
Also remove iswblank, iswdigit, iswxdigit, locale-h, raise,
stdarg-h, some of which perhaps could have been removed earlier.
* configure.ac (_REGEX_AVOID_UCHAR_H): New macro.
2026-05-26 21:57:20 -07:00

235 lines
8.6 KiB
Text
Raw Blame History

# pthread_sigmask.m4
# serial 26
dnl Copyright (C) 2011-2026 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
dnl This file is offered as-is, without any warranty.
AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
[
AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
AC_CHECK_FUNCS_ONCE([pthread_sigmask])
dnl On MinGW pthread_sigmask is just a macro which always returns 0.
dnl It does not exist as a real function, which is required by POSIX.
AC_CACHE_CHECK([whether pthread_sigmask is a macro],
[gl_cv_func_pthread_sigmask_macro],
[AC_EGREP_CPP([headers_define_pthread_sigmask], [
#include <pthread.h>
#include <signal.h>
#if defined _WIN32 && defined pthread_sigmask
headers_define_pthread_sigmask
#endif],
[gl_cv_func_pthread_sigmask_macro=yes],
[gl_cv_func_pthread_sigmask_macro=no])
])
PTHREAD_SIGMASK_LIB=
if test $gl_cv_func_pthread_sigmask_macro = yes; then
dnl pthread_sigmask is a dummy macro.
HAVE_PTHREAD_SIGMASK=0
dnl Make sure to '#undef pthread_sigmask' before defining it.
REPLACE_PTHREAD_SIGMASK=1
else
dnl Test whether the gnulib module 'threadlib' is in use.
dnl Some packages like Emacs use --avoid=threadlib.
dnl Write the symbol in such a way that it does not cause 'aclocal' to pick
dnl the threadlib.m4 file that is installed in $PREFIX/share/aclocal/.
m4_ifdef([gl_][THREADLIB], [
AC_REQUIRE([gl_][THREADLIB])
if test "$gl_threads_api" = posix; then
if test $ac_cv_func_pthread_sigmask = yes; then
dnl pthread_sigmask is available without -lpthread.
:
else
if test -n "$LIBMULTITHREAD"; then
AC_CACHE_CHECK([for pthread_sigmask in $LIBMULTITHREAD],
[gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD],
[gl_saved_LIBS="$LIBS"
LIBS="$LIBS $LIBMULTITHREAD"
AC_LINK_IFELSE(
[AC_LANG_PROGRAM(
[[#include <pthread.h>
#include <signal.h>
]],
[[return pthread_sigmask (0, (sigset_t *) 0, (sigset_t *) 0);]])
],
[gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=yes],
[gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=no])
LIBS="$gl_saved_LIBS"
])
if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
dnl pthread_sigmask is available with -pthread or -lpthread.
PTHREAD_SIGMASK_LIB="$LIBMULTITHREAD"
else
dnl pthread_sigmask is not available at all.
HAVE_PTHREAD_SIGMASK=0
fi
else
dnl pthread_sigmask is not available at all.
HAVE_PTHREAD_SIGMASK=0
fi
fi
else
dnl pthread_sigmask may exist but does not interoperate with the chosen
dnl multithreading facility.
if test $ac_cv_func_pthread_sigmask = yes; then
REPLACE_PTHREAD_SIGMASK=1
else
HAVE_PTHREAD_SIGMASK=0
fi
fi
], [
dnl The module 'threadlib' is not in use, due to --avoid=threadlib being
dnl specified.
dnl The package either has prepared CPPFLAGS and LIBS for use of
dnl POSIX:2008 threads, or wants to build single-threaded programs.
if test $ac_cv_func_pthread_sigmask = yes; then
dnl pthread_sigmask exists and does not require extra libraries.
dnl Assume that it is declared.
:
else
dnl pthread_sigmask either does not exist or needs extra libraries.
HAVE_PTHREAD_SIGMASK=0
dnl Define the symbol rpl_pthread_sigmask, not pthread_sigmask,
dnl so as to not accidentally override the system's pthread_sigmask
dnl symbol from libpthread.
REPLACE_PTHREAD_SIGMASK=1
fi
])
fi
dnl We want to be able to use pthread_sigmask as a thread-safe
dnl replacement of sigprocmask, in both single-threaded and multithreaded
dnl processes. Therefore enforce PTHREAD_SIGMASK_LIB to be empty, whenever
dnl possible.
if test -n "$PTHREAD_SIGMASK_LIB"; then
dnl We get here on glibc ≤ 2.31, NetBSD, OpenBSD ≤ 5.8, AIX.
dnl Except on AIX, pthread_sigmask and sigprocmask are equivalent.
dnl Whereas on AIX, sigprocmask is not allowed in multithreaded processes
dnl <https://www.ibm.com/docs/en/aix/7.2.0?topic=s-sigprocmask-sigsetmask-sigblock-subroutine>.
AC_REQUIRE([AC_CANONICAL_HOST])
case "$host_os" in
aix*) ;;
*)
REPLACE_PTHREAD_SIGMASK=1
AC_DEFINE([PTHREAD_SIGMASK_NOT_IN_LIBC], [1],
[Define to 1 if pthread_sigmask requires linking with some library.])
PTHREAD_SIGMASK_LIB=
;;
esac
fi
AC_SUBST([PTHREAD_SIGMASK_LIB])
dnl For backward compatibility.
LIB_PTHREAD_SIGMASK="$PTHREAD_SIGMASK_LIB"
AC_SUBST([LIB_PTHREAD_SIGMASK])
dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
dnl "$gl_threads_api" = posix, $LTLIBMULTITHREAD and $LIBMULTITHREAD are the
dnl same.
dnl Now test for some bugs in the system function.
if test $HAVE_PTHREAD_SIGMASK = 1; then
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
dnl On FreeBSD 13.0, MidnightBSD 1.1, HP-UX 11.31, Solaris 9, in programs
dnl that are not linked with -lpthread, the pthread_sigmask() function
dnl always returns 0 and has no effect.
if test -z "$PTHREAD_SIGMASK_LIB"; then
case " $LIBS " in
*' -pthread '*) ;;
*' -lpthread '*) ;;
*)
AC_CACHE_CHECK([whether pthread_sigmask works without -lpthread],
[gl_cv_func_pthread_sigmask_in_libc_works],
[
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <pthread.h>
#include <signal.h>
#include <stddef.h>
int main ()
{
sigset_t set;
sigemptyset (&set);
return pthread_sigmask (1729, &set, NULL) != 0;
}]])],
[gl_cv_func_pthread_sigmask_in_libc_works=no],
[gl_cv_func_pthread_sigmask_in_libc_works=yes],
[
changequote(,)dnl
case "$host_os" in
freebsd* | midnightbsd* | hpux* | solaris | solaris2.[2-9]*)
gl_cv_func_pthread_sigmask_in_libc_works="guessing no";;
*)
gl_cv_func_pthread_sigmask_in_libc_works="guessing yes";;
esac
changequote([,])dnl
])
])
case "$gl_cv_func_pthread_sigmask_in_libc_works" in
*no)
REPLACE_PTHREAD_SIGMASK=1
AC_DEFINE([PTHREAD_SIGMASK_INEFFECTIVE], [1],
[Define to 1 if pthread_sigmask may return 0 and have no effect.])
;;
esac;;
esac
fi
dnl On Cygwin 1.7.5, the pthread_sigmask() has a wrong return value
dnl convention: Upon failure, it returns -1 and sets errno.
dnl Likewise on NetBSD 9.3, when libpthread is not in use; see
dnl https://gnats.netbsd.org/cgi-bin/query-pr-single.pl?number=57214 .
AC_CACHE_CHECK([whether pthread_sigmask returns error numbers],
[gl_cv_func_pthread_sigmask_return_works],
[
gl_saved_LIBS="$LIBS"
LIBS="$LIBS $PTHREAD_SIGMASK_LIB"
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <pthread.h>
#include <signal.h>
#include <stddef.h>
int main ()
{
sigset_t set;
sigemptyset (&set);
if (pthread_sigmask (1729, &set, NULL) == -1)
return 1;
return 0;
}]])],
[gl_cv_func_pthread_sigmask_return_works=yes],
[gl_cv_func_pthread_sigmask_return_works=no],
[case "$host_os" in
cygwin*)
gl_cv_func_pthread_sigmask_return_works="guessing no";;
*)
gl_cv_func_pthread_sigmask_return_works="guessing yes";;
esac
])
LIBS="$gl_saved_LIBS"
])
case "$gl_cv_func_pthread_sigmask_return_works" in
*no)
REPLACE_PTHREAD_SIGMASK=1
AC_DEFINE([PTHREAD_SIGMASK_FAILS_WITH_ERRNO], [1],
[Define to 1 if pthread_sigmask(), when it fails, returns -1 and sets errno.])
;;
esac
fi
])
# Prerequisite of lib/pthread_sigmask.c.
AC_DEFUN([gl_PREREQ_PTHREAD_SIGMASK],
[
if test $HAVE_PTHREAD_SIGMASK = 1; then
AC_DEFINE([HAVE_PTHREAD_SIGMASK], [1],
[Define to 1 if the pthread_sigmask function can be used (despite bugs).])
fi
])
Reference in a new issue View git blame Copy permalink