-# pthread_sigmask.m4 serial 7-emacs1
-dnl Copyright (C) 2011 Free Software Foundation, Inc.
+# pthread_sigmask.m4 serial 14
+dnl Copyright (C) 2011-2014 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.
AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
[
+ AC_REQUIRE([gl_SIGNAL_H_DEFAULTS])
+
AC_CHECK_FUNCS_ONCE([pthread_sigmask])
LIB_PTHREAD_SIGMASK=
- dnl gl_THREADLIB is not in use. Assume the application wants
- dnl POSIX semantics.
- if test $ac_cv_func_pthread_sigmask != yes; then
- gl_save_LIBS=$LIBS
- AC_SEARCH_LIBS([pthread_sigmask], [pthread c_r])
- LIBS=$gl_save_LIBS
- if test "$ac_cv_search_pthread_sigmask" = no; then
+
+ 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 $LIBMULTITHREAD],
+ [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD],
+ [gl_save_LIBS="$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_save_LIBS"
+ ])
+ if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
+ dnl pthread_sigmask is available with -lpthread.
+ LIB_PTHREAD_SIGMASK="$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.
+ dnl If "$gl_threads_api" = pth, we could use the function pth_sigmask,
+ dnl but it is equivalent to sigprocmask, so we choose to emulate
+ dnl pthread_sigmask with sigprocmask also in this case. This yields fewer
+ dnl link dependencies.
+ if test $ac_cv_func_pthread_sigmask = yes; then
+ REPLACE_PTHREAD_SIGMASK=1
+ else
HAVE_PTHREAD_SIGMASK=0
- elif test "$ac_cv_search_pthread_sigmask" != 'none required'; then
- LIB_PTHREAD_SIGMASK=$ac_cv_search_pthread_sigmask
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 POSIX:2008
+ dnl threads, or wants to build single-threaded programs.
+ if test $ac_cv_func_pthread_sigmask = yes; then
+ dnl pthread_sigmask exists and does not require extra libraries.
+ dnl Assume that it is declared.
+ :
+ else
+ dnl pthread_sigmask either does not exist or needs extra libraries.
+ HAVE_PTHREAD_SIGMASK=0
+ dnl Define the symbol rpl_pthread_sigmask, not pthread_sigmask,
+ dnl so as to not accidentally override the system's pthread_sigmask
+ dnl symbol from libpthread. This is necessary on IRIX 6.5.
+ REPLACE_PTHREAD_SIGMASK=1
+ fi
+ ])
+
AC_SUBST([LIB_PTHREAD_SIGMASK])
dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
dnl "$gl_threads_api" = posix, $LTLIBMULTITHREAD and $LIBMULTITHREAD are the
dnl same: either both empty or both "-lpthread".
+
+ dnl Now test for some bugs in the system function.
+ if test $HAVE_PTHREAD_SIGMASK = 1; then
+ AC_REQUIRE([AC_PROG_CC])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+ dnl On FreeBSD 6.4, HP-UX 11.31, Solaris 9, in programs that are not linked
+ dnl with -lpthread, the pthread_sigmask() function always returns 0 and has
+ dnl no effect.
+ if test -z "$LIB_PTHREAD_SIGMASK"; then
+ case " $LIBS " in
+ *' -lpthread '*) ;;
+ *)
+ AC_CACHE_CHECK([whether pthread_sigmask works without -lpthread],
+ [gl_cv_func_pthread_sigmask_in_libc_works],
+ [
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+ #include <pthread.h>
+ #include <signal.h>
+ #include <stddef.h>
+ int main ()
+ {
+ sigset_t set;
+ sigemptyset (&set);
+ return pthread_sigmask (1729, &set, NULL) != 0;
+ }]])],
+ [gl_cv_func_pthread_sigmask_in_libc_works=no],
+ [gl_cv_func_pthread_sigmask_in_libc_works=yes],
+ [
+ changequote(,)dnl
+ case "$host_os" in
+ freebsd* | 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 "$gl_cv_func_pthread_sigmask_in_libc_works" in
+ *no)
+ REPLACE_PTHREAD_SIGMASK=1
+ AC_DEFINE([PTHREAD_SIGMASK_INEFFECTIVE], [1],
+ [Define to 1 if pthread_sigmask may return 0 and have no effect.])
+ ;;
+ esac;;
+ esac
+ fi
+
+ dnl On Cygwin 1.7.5, the pthread_sigmask() has a wrong return value
+ dnl convention: Upon failure, it returns -1 and sets errno.
+ AC_CACHE_CHECK([whether pthread_sigmask returns error numbers],
+ [gl_cv_func_pthread_sigmask_return_works],
+ [
+ gl_save_LIBS="$LIBS"
+ LIBS="$LIBS $LIB_PTHREAD_SIGMASK"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <pthread.h>
+#include <signal.h>
+#include <stddef.h>
+int main ()
+{
+ sigset_t set;
+ sigemptyset (&set);
+ if (pthread_sigmask (1729, &set, NULL) == -1)
+ return 1;
+ return 0;
+}]])],
+ [gl_cv_func_pthread_sigmask_return_works=yes],
+ [gl_cv_func_pthread_sigmask_return_works=no],
+ [case "$host_os" in
+ cygwin*)
+ gl_cv_func_pthread_sigmask_return_works="guessing no";;
+ *)
+ gl_cv_func_pthread_sigmask_return_works="guessing yes";;
+ esac
+ ])
+ LIBS="$gl_save_LIBS"
+ ])
+ case "$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
+
+ dnl On IRIX 6.5, in a single-threaded program, pending signals are not
+ dnl immediately delivered when they are unblocked through pthread_sigmask,
+ dnl only a little while later.
+ AC_CACHE_CHECK([whether pthread_sigmask unblocks signals correctly],
+ [gl_cv_func_pthread_sigmask_unblock_works],
+ [
+ case "$host_os" in
+ irix*)
+ gl_cv_func_pthread_sigmask_unblock_works="guessing no";;
+ *)
+ gl_cv_func_pthread_sigmask_unblock_works="guessing yes";;
+ esac
+ m4_ifdef([gl_][THREADLIB],
+ [dnl Link against $LIBMULTITHREAD, not only $LIB_PTHREAD_SIGMASK.
+ dnl Otherwise we get a false positive on those platforms where
+ dnl $gl_cv_func_pthread_sigmask_in_libc_works is "no".
+ gl_save_LIBS=$LIBS
+ LIBS="$LIBS $LIBMULTITHREAD"])
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <pthread.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+static volatile int sigint_occurred;
+static void
+sigint_handler (int sig)
+{
+ sigint_occurred++;
+}
+int main ()
+{
+ sigset_t set;
+ int pid = getpid ();
+ char command[80];
+ signal (SIGINT, sigint_handler);
+ sigemptyset (&set);
+ sigaddset (&set, SIGINT);
+ if (!(pthread_sigmask (SIG_BLOCK, &set, NULL) == 0))
+ return 1;
+ sprintf (command, "sh -c 'sleep 1; kill -%d %d' &", SIGINT, pid);
+ if (!(system (command) == 0))
+ return 2;
+ sleep (2);
+ if (!(sigint_occurred == 0))
+ return 3;
+ if (!(pthread_sigmask (SIG_UNBLOCK, &set, NULL) == 0))
+ return 4;
+ if (!(sigint_occurred == 1)) /* This fails on IRIX. */
+ return 5;
+ return 0;
+}]])],
+ [:],
+ [gl_cv_func_pthread_sigmask_unblock_works=no],
+ [:])
+ m4_ifdef([gl_][THREADLIB], [LIBS=$gl_save_LIBS])
+ ])
+ case "$gl_cv_func_pthread_sigmask_unblock_works" in
+ *no)
+ REPLACE_PTHREAD_SIGMASK=1
+ AC_DEFINE([PTHREAD_SIGMASK_UNBLOCK_BUG], [1],
+ [Define to 1 if pthread_sigmask() unblocks signals incorrectly.])
+ ;;
+ 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
])
HCoop / bpt / emacs.git / blobdiff