1 # pthread_sigmask.m4 serial 10
2 dnl Copyright (C) 2011 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_PTHREAD_SIGMASK],
9 AC_REQUIRE([gl_THREADLIB])
11 AC_CHECK_FUNCS_ONCE([pthread_sigmask])
13 if test "$gl_threads_api" = posix; then
14 if test $ac_cv_func_pthread_sigmask = yes; then
15 dnl pthread_sigmask is available without -lpthread.
18 if test -n "$LIBMULTITHREAD"; then
19 AC_CACHE_CHECK([for pthread_sigmask in $LIBMULTITHREAD],
20 [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD],
22 LIBS="$LIBS $LIBMULTITHREAD"
25 [[#include <pthread.h>
28 [[return pthread_sigmask (0, (sigset_t *) 0, (sigset_t *) 0);]])
30 [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=yes],
31 [gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD=no])
34 if test $gl_cv_func_pthread_sigmask_in_LIBMULTITHREAD = yes; then
35 dnl pthread_sigmask is available with -lpthread.
36 LIB_PTHREAD_SIGMASK="$LIBMULTITHREAD"
38 dnl pthread_sigmask is not available at all.
39 HAVE_PTHREAD_SIGMASK=0
42 dnl pthread_sigmask is not available at all.
43 HAVE_PTHREAD_SIGMASK=0
47 dnl pthread_sigmask may exist but does not interoperate with the chosen
48 dnl multithreading facility.
49 dnl If "$gl_threads_api" = pth, we could use the function pth_sigmask,
50 dnl but it is equivalent to sigprocmask, so we choose to emulate
51 dnl pthread_sigmask with sigprocmask also in this case. This yields fewer
52 dnl link dependencies.
53 if test $ac_cv_func_pthread_sigmask = yes; then
54 REPLACE_PTHREAD_SIGMASK=1
56 HAVE_PTHREAD_SIGMASK=0
59 AC_SUBST([LIB_PTHREAD_SIGMASK])
60 dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
61 dnl "$gl_threads_api" = posix, $LTLIBMULTITHREAD and $LIBMULTITHREAD are the
62 dnl same: either both empty or both "-lpthread".
64 dnl Now test for some bugs in the system function.
65 if test $HAVE_PTHREAD_SIGMASK = 1; then
66 AC_REQUIRE([AC_PROG_CC])
67 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
69 dnl On FreeBSD 6.4, HP-UX 11.31, Solaris 9, in programs that are not linked
70 dnl with -lpthread, the pthread_sigmask() function always returns 0 and has
72 if test -z "$LIB_PTHREAD_SIGMASK"; then
73 AC_CACHE_CHECK([whether pthread_sigmask works without -lpthread],
74 [gl_cv_func_pthread_sigmask_in_libc_works],
85 return pthread_sigmask (1729, &set, NULL) != 0;
87 [gl_cv_func_pthread_sigmask_in_libc_works=no],
88 [gl_cv_func_pthread_sigmask_in_libc_works=yes],
92 freebsd* | hpux* | solaris | solaris2.[2-9]*)
93 gl_cv_func_pthread_sigmask_in_libc_works="guessing no";;
95 gl_cv_func_pthread_sigmask_in_libc_works="guessing yes";;
100 case "$gl_cv_func_pthread_sigmask_in_libc_works" in
102 REPLACE_PTHREAD_SIGMASK=1
103 AC_DEFINE([PTHREAD_SIGMASK_INEFFECTIVE], [1],
104 [Define to 1 if pthread_sigmask() may returns 0 and have no effect.])
109 dnl On Cygwin 1.7.5, the pthread_sigmask() has a wrong return value
110 dnl convention: Upon failure, it returns -1 and sets errno.
111 AC_CACHE_CHECK([whether pthread_sigmask returns error numbers],
112 [gl_cv_func_pthread_sigmask_return_works],
115 LIBS="$LIBS $LIB_PTHREAD_SIGMASK"
125 if (pthread_sigmask (1729, &set, NULL) == -1)
129 [gl_cv_func_pthread_sigmask_return_works=yes],
130 [gl_cv_func_pthread_sigmask_return_works=no],
133 gl_cv_func_pthread_sigmask_return_works="guessing no";;
135 gl_cv_func_pthread_sigmask_return_works="guessing yes";;
140 case "$gl_cv_func_pthread_sigmask_return_works" in
142 REPLACE_PTHREAD_SIGMASK=1
143 AC_DEFINE([PTHREAD_SIGMASK_FAILS_WITH_ERRNO], [1],
144 [Define to 1 if pthread_sigmask(), when it fails, returns -1 and sets errno.])
148 dnl On IRIX 6.5, in a single-threaded program, pending signals are not
149 dnl immediately delivered when they are unblocked through pthread_sigmask,
150 dnl only a little while later.
151 AC_CACHE_CHECK([whether pthread_sigmask unblocks signals correctly],
152 [gl_cv_func_pthread_sigmask_unblock_works],
156 gl_cv_func_pthread_sigmask_unblock_works="guessing no";;
158 gl_cv_func_pthread_sigmask_unblock_works="guessing yes";;
160 dnl Here we link against $LIBMULTITHREAD, not only $LIB_PTHREAD_SIGMASK,
161 dnl otherwise we get a false positive on those platforms where
162 dnl $gl_cv_func_pthread_sigmask_in_libc_works is "no".
164 LIBS="$LIBS $LIBMULTITHREAD"
172 static volatile int sigint_occurred;
174 sigint_handler (int sig)
183 signal (SIGINT, sigint_handler);
185 sigaddset (&set, SIGINT);
186 if (!(pthread_sigmask (SIG_BLOCK, &set, NULL) == 0))
188 sprintf (command, "sh -c 'sleep 1; kill -%d %d' &", SIGINT, pid);
189 if (!(system (command) == 0))
192 if (!(sigint_occurred == 0))
194 if (!(pthread_sigmask (SIG_UNBLOCK, &set, NULL) == 0))
196 if (!(sigint_occurred == 1)) /* This fails on IRIX. */
201 [gl_cv_func_pthread_sigmask_unblock_works=no],
205 case "$gl_cv_func_pthread_sigmask_unblock_works" in
207 REPLACE_PTHREAD_SIGMASK=1
208 AC_DEFINE([PTHREAD_SIGMASK_UNBLOCK_BUG], [1],
209 [Define to 1 if pthread_sigmask() unblocks signals incorrectly.])
215 # Prerequisite of lib/pthread_sigmask.c.
216 AC_DEFUN([gl_PREREQ_PTHREAD_SIGMASK],
218 if test $HAVE_PTHREAD_SIGMASK = 1; then
219 AC_DEFINE([HAVE_PTHREAD_SIGMASK], [1],
220 [Define to 1 if the pthread_sigmask function can be used (despite bugs).])