-# pthread_sigmask.m4 serial 6
+# pthread_sigmask.m4 serial 12
dnl Copyright (C) 2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
[
AC_CHECK_FUNCS_ONCE([pthread_sigmask])
LIB_PTHREAD_SIGMASK=
- m4_ifdef([gl_THREADLIB], [
- AC_REQUIRE([gl_THREADLIB])
+
+ 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.
HAVE_PTHREAD_SIGMASK=0
fi
fi
- ] ,[
- dnl If module 'threadlib' is not in use, assume all programs will be
- dnl single-threaded.
+ ], [
+ 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 $ac_cv_func_pthread_sigmask = yes; then
- REPLACE_PTHREAD_SIGMASK=1
+ dnl pthread_sigmask exists and does not require extra libraries.
+ dnl Assume that it is declared.
+ :
else
+ dnl pthread_sigmask either does not exist or needs extra libraries.
HAVE_PTHREAD_SIGMASK=0
+ dnl Define the symbol rpl_pthread_sigmask, not pthread_sigmask,
+ dnl so as to not accidentally override the system's pthread_sigmask
+ dnl symbol from libpthread. This is necessary on IRIX 6.5.
+ REPLACE_PTHREAD_SIGMASK=1
fi
])
+
AC_SUBST([LIB_PTHREAD_SIGMASK])
dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
dnl "$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
+ 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 returns 0 and have no effect.])
+ ;;
+ 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
+ dnl Here we 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 $LIBMULTITHREAD"
+ AC_RUN_IFELSE(
+ [AC_LANG_SOURCE([[
+#include <pthread.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+static volatile int sigint_occurred;
+static void
+sigint_handler (int sig)
+{
+ sigint_occurred++;
+}
+int main ()
+{
+ sigset_t set;
+ int pid = getpid ();
+ char command[80];
+ signal (SIGINT, sigint_handler);
+ sigemptyset (&set);
+ sigaddset (&set, SIGINT);
+ if (!(pthread_sigmask (SIG_BLOCK, &set, NULL) == 0))
+ return 1;
+ sprintf (command, "sh -c 'sleep 1; kill -%d %d' &", SIGINT, pid);
+ if (!(system (command) == 0))
+ return 2;
+ sleep (2);
+ if (!(sigint_occurred == 0))
+ return 3;
+ if (!(pthread_sigmask (SIG_UNBLOCK, &set, NULL) == 0))
+ return 4;
+ if (!(sigint_occurred == 1)) /* This fails on IRIX. */
+ return 5;
+ return 0;
+}]])],
+ [:],
+ [gl_cv_func_pthread_sigmask_unblock_works=no],
+ [:])
+ LIBS="$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
])