+++ /dev/null
-# lock.m4 serial 7 (gettext-0.17)
-dnl Copyright (C) 2005-2007 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 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 Sets the variables LIBTHREAD and LTLIBTHREAD to the linker options for use
-dnl in a Makefile (LIBTHREAD for use without libtool, LTLIBTHREAD for use with
-dnl libtool).
-dnl Sets the variables LIBMULTITHREAD and LTLIBMULTITHREAD similarly, for
-dnl programs that really need multithread functionality. The difference
-dnl between LIBTHREAD and LIBMULTITHREAD is that on platforms supporting weak
-dnl symbols, typically LIBTHREAD="" whereas LIBMULTITHREAD="-lpthread".
-dnl Adds to CPPFLAGS the flag -D_REENTRANT or -D_THREAD_SAFE if needed for
-dnl multithread-safe programs.
-
-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
- dnl declarations, on AIX 5 at least. Therefore it must come early.
- AC_BEFORE([$0], [gl_FUNC_GLIBC_UNLOCKED_IO])dnl
- AC_BEFORE([$0], [gl_ARGP])dnl
-
- AC_REQUIRE([AC_CANONICAL_HOST])
- dnl _GNU_SOURCE is needed for pthread_rwlock_t on glibc systems.
- dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes
- dnl AC_GNU_SOURCE.
- m4_ifdef([AC_USE_SYSTEM_EXTENSIONS],
- [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
- [AC_REQUIRE([AC_GNU_SOURCE])])
- dnl Check for multithreading.
- AC_ARG_ENABLE(threads,
-AC_HELP_STRING([--enable-threads={posix|solaris|pth|win32}], [specify multithreading API])
-AC_HELP_STRING([--disable-threads], [build without multithread safety]),
- [gl_use_threads=$enableval],
- [case "$host_os" in
- dnl Disable multithreading by default on OSF/1, because it interferes
- dnl with fork()/exec(): When msgexec is linked with -lpthread, its child
- dnl process gets an endless segmentation fault inside execvp().
- osf*) gl_use_threads=no ;;
- *) gl_use_threads=yes ;;
- esac
- ])
- if test "$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=
- LIBMULTITHREAD=
- LTLIBMULTITHREAD=
- if test "$gl_use_threads" != no; then
- dnl Check whether the compiler and linker support weak declarations.
- AC_MSG_CHECKING([whether imported symbols can be declared weak])
- gl_have_weak=no
- AC_TRY_LINK([extern void xyzzy ();
-#pragma weak xyzzy], [xyzzy();], [gl_have_weak=yes])
- AC_MSG_RESULT([$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>. It's added above, in gl_LOCK_EARLY_BODY.
- AC_CHECK_HEADER(pthread.h, gl_have_pthread_h=yes, gl_have_pthread_h=no)
- if test "$gl_have_pthread_h" = yes; then
- # Other possible tests:
- # -lpthreads (FSU threads, PCthreads)
- # -lgthreads
- gl_have_pthread=
- # Test whether both pthread_mutex_lock and pthread_mutexattr_init exist
- # in libc. IRIX 6.5 has the first one in both libc and libpthread, but
- # the second one only in libpthread, and lock.c needs it.
- AC_TRY_LINK([#include <pthread.h>],
- [pthread_mutex_lock((pthread_mutex_t*)0);
- pthread_mutexattr_init((pthread_mutexattr_t*)0);],
- [gl_have_pthread=yes])
- # Test for libpthread by looking for pthread_kill. (Not pthread_self,
- # since it is defined as a macro on OSF/1.)
- if test -n "$gl_have_pthread"; then
- # The program links fine without libpthread. But it may actually
- # need to link with libpthread in order to create multiple threads.
- AC_CHECK_LIB(pthread, pthread_kill,
- [LIBMULTITHREAD=-lpthread LTLIBMULTITHREAD=-lpthread
- # On Solaris and HP-UX, most pthread functions exist also in libc.
- # Therefore pthread_in_use() needs to actually try to create a
- # thread: pthread_create from libc will fail, whereas
- # pthread_create will actually create a thread.
- case "$host_os" in
- solaris* | hpux*)
- AC_DEFINE([PTHREAD_IN_USE_DETECTION_HARD], 1,
- [Define if the pthread_in_use() detection is hard.])
- esac
- ])
- else
- # Some library is needed. Try libpthread and libc_r.
- AC_CHECK_LIB(pthread, pthread_kill,
- [gl_have_pthread=yes
- LIBTHREAD=-lpthread LTLIBTHREAD=-lpthread
- LIBMULTITHREAD=-lpthread LTLIBMULTITHREAD=-lpthread])
- if test -z "$gl_have_pthread"; then
- # For FreeBSD 4.
- AC_CHECK_LIB(c_r, pthread_kill,
- [gl_have_pthread=yes
- LIBTHREAD=-lc_r LTLIBTHREAD=-lc_r
- LIBMULTITHREAD=-lc_r LTLIBMULTITHREAD=-lc_r])
- fi
- fi
- if test -n "$gl_have_pthread"; then
- gl_threads_api=posix
- AC_DEFINE([USE_POSIX_THREADS], 1,
- [Define if the POSIX multithreading library can be used.])
- if test -n "$LIBMULTITHREAD" || test -n "$LTLIBMULTITHREAD"; then
- if test $gl_have_weak = yes; then
- AC_DEFINE([USE_POSIX_THREADS_WEAK], 1,
- [Define if references to the POSIX multithreading library should be made weak.])
- LIBTHREAD=
- LTLIBTHREAD=
- fi
- fi
- # OSF/1 4.0 and MacOS X 10.1 lack the pthread_rwlock_t type and the
- # pthread_rwlock_* functions.
- AC_CHECK_TYPE([pthread_rwlock_t],
- [AC_DEFINE([HAVE_PTHREAD_RWLOCK], 1,
- [Define if the POSIX multithreading library has read/write locks.])],
- [],
- [#include <pthread.h>])
- # glibc defines PTHREAD_MUTEX_RECURSIVE as enum, not as a macro.
- AC_TRY_COMPILE([#include <pthread.h>],
- [#if __FreeBSD__ == 4
-error "No, in FreeBSD 4.0 recursive mutexes actually don't work."
-#else
-int x = (int)PTHREAD_MUTEX_RECURSIVE;
-return !x;
-#endif],
- [AC_DEFINE([HAVE_PTHREAD_MUTEX_RECURSIVE], 1,
- [Define if the <pthread.h> defines PTHREAD_MUTEX_RECURSIVE.])])
- fi
- fi
- fi
- if test -z "$gl_have_pthread"; then
- if test "$gl_use_threads" = yes || test "$gl_use_threads" = solaris; then
- gl_have_solaristhread=
- gl_save_LIBS="$LIBS"
- LIBS="$LIBS -lthread"
- AC_TRY_LINK([#include <thread.h>
-#include <synch.h>],
- [thr_self();],
- [gl_have_solaristhread=yes])
- LIBS="$gl_save_LIBS"
- if test -n "$gl_have_solaristhread"; then
- gl_threads_api=solaris
- LIBTHREAD=-lthread
- LTLIBTHREAD=-lthread
- LIBMULTITHREAD="$LIBTHREAD"
- LTLIBMULTITHREAD="$LTLIBTHREAD"
- AC_DEFINE([USE_SOLARIS_THREADS], 1,
- [Define if the old Solaris multithreading library can be used.])
- if test $gl_have_weak = yes; then
- AC_DEFINE([USE_SOLARIS_THREADS_WEAK], 1,
- [Define if references to the old Solaris multithreading library should be made weak.])
- LIBTHREAD=
- LTLIBTHREAD=
- fi
- fi
- fi
- fi
- if test "$gl_use_threads" = pth; then
- gl_save_CPPFLAGS="$CPPFLAGS"
- AC_LIB_LINKFLAGS(pth)
- gl_have_pth=
- gl_save_LIBS="$LIBS"
- LIBS="$LIBS -lpth"
- AC_TRY_LINK([#include <pth.h>], [pth_self();], gl_have_pth=yes)
- LIBS="$gl_save_LIBS"
- if test -n "$gl_have_pth"; then
- gl_threads_api=pth
- LIBTHREAD="$LIBPTH"
- LTLIBTHREAD="$LTLIBPTH"
- LIBMULTITHREAD="$LIBTHREAD"
- LTLIBMULTITHREAD="$LTLIBTHREAD"
- AC_DEFINE([USE_PTH_THREADS], 1,
- [Define if the GNU Pth multithreading library can be used.])
- if test -n "$LIBMULTITHREAD" || test -n "$LTLIBMULTITHREAD"; then
- if test $gl_have_weak = yes; then
- AC_DEFINE([USE_PTH_THREADS_WEAK], 1,
- [Define if references to the GNU Pth multithreading library should be made weak.])
- LIBTHREAD=
- LTLIBTHREAD=
- fi
- fi
- else
- CPPFLAGS="$gl_save_CPPFLAGS"
- fi
- fi
- if test -z "$gl_have_pthread"; then
- if test "$gl_use_threads" = yes || test "$gl_use_threads" = win32; then
- if { case "$host_os" in
- mingw*) true;;
- *) false;;
- esac
- }; then
- gl_threads_api=win32
- AC_DEFINE([USE_WIN32_THREADS], 1,
- [Define if the Win32 multithreading API can be used.])
- fi
- fi
- fi
- fi
- AC_MSG_CHECKING([for multithread API to use])
- AC_MSG_RESULT([$gl_threads_api])
- AC_SUBST(LIBTHREAD)
- 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
-])
-
-# Prerequisites of lib/lock.c.
-AC_DEFUN([gl_PREREQ_LOCK], [
- AC_REQUIRE([AC_C_INLINE])
-])
-
-dnl Survey of platforms:
-dnl
-dnl Platform Available Compiler Supports test-lock
-dnl flavours option weak result
-dnl --------------- --------- --------- -------- ---------
-dnl Linux 2.4/glibc posix -lpthread Y OK
-dnl
-dnl GNU Hurd/glibc posix
-dnl
-dnl FreeBSD 5.3 posix -lc_r Y
-dnl posix -lkse ? Y
-dnl posix -lpthread ? Y
-dnl posix -lthr Y
-dnl
-dnl FreeBSD 5.2 posix -lc_r Y
-dnl posix -lkse Y
-dnl posix -lthr Y
-dnl
-dnl FreeBSD 4.0,4.10 posix -lc_r Y OK
-dnl
-dnl NetBSD 1.6 --
-dnl
-dnl OpenBSD 3.4 posix -lpthread Y OK
-dnl
-dnl MacOS X 10.[123] posix -lpthread Y OK
-dnl
-dnl Solaris 7,8,9 posix -lpthread Y Sol 7,8: 0.0; Sol 9: OK
-dnl solaris -lthread Y Sol 7,8: 0.0; Sol 9: OK
-dnl
-dnl HP-UX 11 posix -lpthread N (cc) OK
-dnl Y (gcc)
-dnl
-dnl IRIX 6.5 posix -lpthread Y 0.5
-dnl
-dnl AIX 4.3,5.1 posix -lpthread N AIX 4: 0.5; AIX 5: OK
-dnl
-dnl OSF/1 4.0,5.1 posix -pthread (cc) N OK
-dnl -lpthread (gcc) Y
-dnl
-dnl Cygwin posix -lpthread Y OK
-dnl
-dnl Any of the above pth -lpth 0.0
-dnl
-dnl Mingw win32 N OK
-dnl
-dnl BeOS 5 --
-dnl
-dnl The test-lock result shows what happens if in test-lock.c EXPLICIT_YIELD is
-dnl turned off:
-dnl OK if all three tests terminate OK,
-dnl 0.5 if the first test terminates OK but the second one loops endlessly,
-dnl 0.0 if the first test already loops endlessly.
git.annexia.org / libguestfs.git / blobdiff