-# lock.m4 serial 1 (gettext-0.15)
-dnl Copyright (C) 2005 Free Software Foundation, Inc.
+# lock.m4 serial 8 (gettext-0.18)
+dnl Copyright (C) 2005-2008 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 From Bruno Haible.
+dnl gl_LOCK
+dnl -------
dnl Tests for a multithreading library to be used.
dnl Defines at most one of the macros USE_POSIX_THREADS, USE_SOLARIS_THREADS,
dnl USE_PTH_THREADS, USE_WIN32_THREADS
dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for
dnl multithread-safe programs.
-AC_DEFUN([gl_LOCK],
+AC_DEFUN([gl_LOCK_EARLY],
+[
+ AC_REQUIRE([gl_LOCK_EARLY_BODY])
+])
+
+dnl The guts of gl_LOCK_EARLY. Needs to be expanded only once.
+
+AC_DEFUN([gl_LOCK_EARLY_BODY],
[
dnl Ordering constraints: This macro modifies CPPFLAGS in a way that
dnl influences the result of the autoconf tests that test for *_unlocked
AC_BEFORE([$0], [gl_ARGP])dnl
AC_REQUIRE([AC_CANONICAL_HOST])
- AC_REQUIRE([AC_GNU_SOURCE]) dnl needed for pthread_rwlock_t on glibc systems
+ dnl _GNU_SOURCE is needed for pthread_rwlock_t on glibc systems.
+ dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes
+ dnl AC_GNU_SOURCE.
+ m4_ifdef([AC_USE_SYSTEM_EXTENSIONS],
+ [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
+ [AC_REQUIRE([AC_GNU_SOURCE])])
dnl Check for multithreading.
+ m4_divert_text([DEFAULTS], [gl_use_threads_default=])
AC_ARG_ENABLE(threads,
AC_HELP_STRING([--enable-threads={posix|solaris|pth|win32}], [specify multithreading API])
AC_HELP_STRING([--disable-threads], [build without multithread safety]),
- gl_use_threads=$enableval, gl_use_threads=yes)
+ [gl_use_threads=$enableval],
+ [if test -n "$gl_use_threads_default"; then
+ gl_use_threads="$gl_use_threads_default"
+ else
+ case "$host_os" in
+ dnl Disable multithreading by default on OSF/1, because it interferes
+ dnl with fork()/exec(): When msgexec is linked with -lpthread, its
+ dnl child process gets an endless segmentation fault inside execvp().
+ osf*) gl_use_threads=no ;;
+ *) gl_use_threads=yes ;;
+ esac
+ fi
+ ])
+ if test "$gl_use_threads" = yes || test "$gl_use_threads" = posix; then
+ # For using <pthread.h>:
+ case "$host_os" in
+ osf*)
+ # On OSF/1, the compiler needs the flag -D_REENTRANT so that it
+ # groks <pthread.h>. cc also understands the flag -pthread, but
+ # we don't use it because 1. gcc-2.95 doesn't understand -pthread,
+ # 2. putting a flag into CPPFLAGS that has an effect on the linker
+ # causes the AC_TRY_LINK test below to succeed unexpectedly,
+ # leading to wrong values of LIBTHREAD and LTLIBTHREAD.
+ CPPFLAGS="$CPPFLAGS -D_REENTRANT"
+ ;;
+ esac
+ # Some systems optimize for single-threaded programs by default, and
+ # need special flags to disable these optimizations. For example, the
+ # definition of 'errno' in <errno.h>.
+ case "$host_os" in
+ aix* | freebsd*) CPPFLAGS="$CPPFLAGS -D_THREAD_SAFE" ;;
+ solaris*) CPPFLAGS="$CPPFLAGS -D_REENTRANT" ;;
+ esac
+ fi
+])
+
+dnl The guts of gl_LOCK. Needs to be expanded only once.
+
+AC_DEFUN([gl_LOCK_BODY],
+[
+ AC_REQUIRE([gl_LOCK_EARLY_BODY])
gl_threads_api=none
LIBTHREAD=
LTLIBTHREAD=
AC_MSG_RESULT([$gl_have_weak])
if test "$gl_use_threads" = yes || test "$gl_use_threads" = posix; then
# On OSF/1, the compiler needs the flag -pthread or -D_REENTRANT so that
- # it groks <pthread.h>.
- gl_save_CPPFLAGS="$CPPFLAGS"
- CPPFLAGS="$CPPFLAGS -D_REENTRANT"
+ # it groks <pthread.h>. It's added above, in gl_LOCK_EARLY_BODY.
AC_CHECK_HEADER(pthread.h, gl_have_pthread_h=yes, gl_have_pthread_h=no)
- CPPFLAGS="$gl_save_CPPFLAGS"
if test "$gl_have_pthread_h" = yes; then
# Other possible tests:
# -lpthreads (FSU threads, PCthreads)
# -lgthreads
- case "$host_os" in
- osf*)
- # On OSF/1, the compiler needs the flag -D_REENTRANT so that it
- # groks <pthread.h>. cc also understands the flag -pthread, but
- # we don't use it because 1. gcc-2.95 doesn't understand -pthread,
- # 2. putting a flag into CPPFLAGS that has an effect on the linker
- # causes the AC_TRY_LINK test below to succeed unexpectedly,
- # leading to wrong values of LIBTHREAD and LTLIBTHREAD.
- CPPFLAGS="$CPPFLAGS -D_REENTRANT"
- ;;
- esac
gl_have_pthread=
# Test whether both pthread_mutex_lock and pthread_mutexattr_init exist
# in libc. IRIX 6.5 has the first one in both libc and libpthread, but
error "No, in FreeBSD 4.0 recursive mutexes actually don't work."
#else
int x = (int)PTHREAD_MUTEX_RECURSIVE;
+return !x;
#endif],
[AC_DEFINE([HAVE_PTHREAD_MUTEX_RECURSIVE], 1,
[Define if the <pthread.h> defines PTHREAD_MUTEX_RECURSIVE.])])
- # Some systems optimize for single-threaded programs by default, and
- # need special flags to disable these optimizations. For example, the
- # definition of 'errno' in <errno.h>.
- case "$host_os" in
- aix* | freebsd*) CPPFLAGS="$CPPFLAGS -D_THREAD_SAFE" ;;
- solaris*) CPPFLAGS="$CPPFLAGS -D_REENTRANT" ;;
- esac
fi
fi
fi
AC_SUBST(LTLIBTHREAD)
AC_SUBST(LIBMULTITHREAD)
AC_SUBST(LTLIBMULTITHREAD)
+])
+
+AC_DEFUN([gl_LOCK],
+[
+ AC_REQUIRE([gl_LOCK_EARLY])
+ AC_REQUIRE([gl_LOCK_BODY])
gl_PREREQ_LOCK
])
AC_REQUIRE([AC_C_INLINE])
])
+
+dnl gl_DISABLE_THREADS
+dnl ------------------
+dnl Sets the gl_LOCK default so that threads are not used by default.
+dnl The user can still override it at installation time, by using the
+dnl configure option '--enable-threads'.
+
+AC_DEFUN([gl_DISABLE_THREADS], [
+ m4_divert_text([INIT_PREPARE], [gl_use_threads_default=no])
+])
+
+
dnl Survey of platforms:
dnl
dnl Platform Available Compiler Supports test-lock
projects / gnulib.git / blobdiff