1 # pthread_sigmask.m4 serial 9
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_CHECK_FUNCS_ONCE([pthread_sigmask])
11 m4_ifdef([gl_THREADLIB], [
12 AC_REQUIRE([gl_THREADLIB])
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
60 dnl gl_THREADLIB is not in use. Assume the application wants
62 if test $ac_cv_func_pthread_sigmask != yes; then
64 AC_SEARCH_LIBS([pthread_sigmask], [pthread c_r])
66 if test "$ac_cv_search_pthread_sigmask" = no; then
67 HAVE_PTHREAD_SIGMASK=0
68 elif test "$ac_cv_search_pthread_sigmask" != 'none required'; then
69 LIB_PTHREAD_SIGMASK=$ac_cv_search_pthread_sigmask
73 AC_SUBST([LIB_PTHREAD_SIGMASK])
74 dnl We don't need a variable LTLIB_PTHREAD_SIGMASK, because when
75 dnl "$gl_threads_api" = posix, $LTLIBMULTITHREAD and $LIBMULTITHREAD are the
76 dnl same: either both empty or both "-lpthread".
78 dnl Now test for some bugs in the system function.
79 if test $HAVE_PTHREAD_SIGMASK = 1; then
80 AC_REQUIRE([AC_PROG_CC])
81 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
83 dnl On FreeBSD 6.4, HP-UX 11.31, Solaris 9, in programs that are not linked
84 dnl with -lpthread, the pthread_sigmask() function always returns 0 and has
86 if test -z "$LIB_PTHREAD_SIGMASK"; then
87 AC_CACHE_CHECK([whether pthread_sigmask works without -lpthread],
88 [gl_cv_func_pthread_sigmask_in_libc_works],
99 return pthread_sigmask (1729, &set, NULL) != 0;
101 [gl_cv_func_pthread_sigmask_in_libc_works=no],
102 [gl_cv_func_pthread_sigmask_in_libc_works=yes],
106 freebsd* | hpux* | solaris | solaris2.[2-9]*)
107 gl_cv_func_pthread_sigmask_in_libc_works="guessing no";;
109 gl_cv_func_pthread_sigmask_in_libc_works="guessing yes";;
114 case "$gl_cv_func_pthread_sigmask_in_libc_works" in
116 REPLACE_PTHREAD_SIGMASK=1
117 AC_DEFINE([PTHREAD_SIGMASK_INEFFECTIVE], [1],
118 [Define to 1 if pthread_sigmask() may returns 0 and have no effect.])
123 dnl On Cygwin 1.7.5, the pthread_sigmask() has a wrong return value
124 dnl convention: Upon failure, it returns -1 and sets errno.
125 AC_CACHE_CHECK([whether pthread_sigmask returns error numbers],
126 [gl_cv_func_pthread_sigmask_return_works],
129 LIBS="$LIBS $LIB_PTHREAD_SIGMASK"
139 if (pthread_sigmask (1729, &set, NULL) == -1)
143 [gl_cv_func_pthread_sigmask_return_works=yes],
144 [gl_cv_func_pthread_sigmask_return_works=no],
147 gl_cv_func_pthread_sigmask_return_works="guessing no";;
149 gl_cv_func_pthread_sigmask_return_works="guessing yes";;
154 case "$gl_cv_func_pthread_sigmask_return_works" in
156 REPLACE_PTHREAD_SIGMASK=1
157 AC_DEFINE([PTHREAD_SIGMASK_FAILS_WITH_ERRNO], [1],
158 [Define to 1 if pthread_sigmask(), when it fails, returns -1 and sets errno.])
162 dnl On IRIX 6.5, in a single-threaded program, pending signals are not
163 dnl immediately delivered when they are unblocked through pthread_sigmask,
164 dnl only a little while later.
165 AC_CACHE_CHECK([whether pthread_sigmask unblocks signals correctly],
166 [gl_cv_func_pthread_sigmask_unblock_works],
170 gl_cv_func_pthread_sigmask_unblock_works="guessing no";;
172 gl_cv_func_pthread_sigmask_unblock_works="guessing yes";;
174 dnl Here we link against $LIBMULTITHREAD, not only $LIB_PTHREAD_SIGMASK,
175 dnl otherwise we get a false positive on those platforms where
176 dnl $gl_cv_func_pthread_sigmask_in_libc_works is "no".
178 LIBS="$LIBS $LIBMULTITHREAD"
186 static volatile int sigint_occurred;
188 sigint_handler (int sig)
197 signal (SIGINT, sigint_handler);
199 sigaddset (&set, SIGINT);
200 if (!(pthread_sigmask (SIG_BLOCK, &set, NULL) == 0))
202 sprintf (command, "sh -c 'sleep 1; kill -%d %d' &", SIGINT, pid);
203 if (!(system (command) == 0))
206 if (!(sigint_occurred == 0))
208 if (!(pthread_sigmask (SIG_UNBLOCK, &set, NULL) == 0))
210 if (!(sigint_occurred == 1)) /* This fails on IRIX. */
215 [gl_cv_func_pthread_sigmask_unblock_works=no],
219 case "$gl_cv_func_pthread_sigmask_unblock_works" in
221 REPLACE_PTHREAD_SIGMASK=1
222 AC_DEFINE([PTHREAD_SIGMASK_UNBLOCK_BUG], [1],
223 [Define to 1 if pthread_sigmask() unblocks signals incorrectly.])
229 # Prerequisite of lib/pthread_sigmask.c.
230 AC_DEFUN([gl_PREREQ_PTHREAD_SIGMASK],
232 if test $HAVE_PTHREAD_SIGMASK = 1; then
233 AC_DEFINE([HAVE_PTHREAD_SIGMASK], [1],
234 [Define to 1 if the pthread_sigmask function can be used (despite bugs).])