# $Id: mutex.ac,v 11.38 2002/07/25 20:07:52 sue Exp $# POSIX pthreads tests: inter-process safe and intra-process only.## We need to run a test here, because the PTHREAD_PROCESS_SHARED flag compiles# fine on problematic systems, but won't actually work.  This is a problem for# cross-compilation environments.  I think inter-process mutexes are as likely# to fail in cross-compilation environments as real ones (especially since the# likely cross-compilation environment is Linux, where inter-process mutexes# don't currently work -- the latest estimate I've heard is Q1 2002, as part# of IBM's NGPT package).  So:## If checking for inter-process pthreads mutexes:#	If it's local, run a test.#	If it's a cross-compilation, fail.## If the user specified pthreads mutexes and we're checking for intra-process# mutexes only:#	If it's local, run a test.#	If it's a cross-compilation, run a link-test.## So, the thing you can't do here is configure for inter-process POSIX pthread# mutexes when cross-compiling.  Since we're using the GNU/Cygnus toolchain for# cross-compilation, the target system is likely Linux or *BSD, so we're doing# the right thing.AC_DEFUN(AM_PTHREADS_SHARED, [AC_TRY_RUN([#include <pthread.h>main() {	pthread_cond_t cond;	pthread_mutex_t mutex;	pthread_condattr_t condattr;	pthread_mutexattr_t mutexattr;	exit (	pthread_condattr_init(&condattr) ||	pthread_condattr_setpshared(&condattr, PTHREAD_PROCESS_SHARED) ||	pthread_mutexattr_init(&mutexattr) ||	pthread_mutexattr_setpshared(&mutexattr, PTHREAD_PROCESS_SHARED) ||	pthread_cond_init(&cond, &condattr) ||	pthread_mutex_init(&mutex, &mutexattr) ||	pthread_mutex_lock(&mutex) ||	pthread_mutex_unlock(&mutex) ||	pthread_mutex_destroy(&mutex) ||	pthread_cond_destroy(&cond) ||	pthread_condattr_destroy(&condattr) ||	pthread_mutexattr_destroy(&mutexattr));}], [db_cv_mutex="$1"],, [db_cv_mutex="no"])])AC_DEFUN(AM_PTHREADS_PRIVATE, [AC_TRY_RUN([#include <pthread.h>main() {	pthread_cond_t cond;	pthread_mutex_t mutex;	pthread_condattr_t condattr;	pthread_mutexattr_t mutexattr;	exit (	pthread_condattr_init(&condattr) ||	pthread_mutexattr_init(&mutexattr) ||	pthread_cond_init(&cond, &condattr) ||	pthread_mutex_init(&mutex, &mutexattr) ||	pthread_mutex_lock(&mutex) ||	pthread_mutex_unlock(&mutex) ||	pthread_mutex_destroy(&mutex) ||	pthread_cond_destroy(&cond) ||	pthread_condattr_destroy(&condattr) ||	pthread_mutexattr_destroy(&mutexattr));}], [db_cv_mutex="$1"],,AC_TRY_LINK([#include <pthread.h>],[	pthread_cond_t cond;	pthread_mutex_t mutex;	pthread_condattr_t condattr;	pthread_mutexattr_t mutexattr;	exit (	pthread_condattr_init(&condattr) ||	pthread_mutexattr_init(&mutexattr) ||	pthread_cond_init(&cond, &condattr) ||	pthread_mutex_init(&mutex, &mutexattr) ||	pthread_mutex_lock(&mutex) ||	pthread_mutex_unlock(&mutex) ||	pthread_mutex_destroy(&mutex) ||	pthread_cond_destroy(&cond) ||	pthread_condattr_destroy(&condattr) ||	pthread_mutexattr_destroy(&mutexattr));], [db_cv_mutex="$1"]))])# Figure out mutexes for this compiler/architecture.AC_DEFUN(AM_DEFINE_MUTEXES, [# Mutexes we don't test for, but want the #defines to exist for# other ports.AH_TEMPLATE(HAVE_MUTEX_VMS, [Define to 1 to use VMS mutexes.])AH_TEMPLATE(HAVE_MUTEX_VXWORKS, [Define to 1 to use VxWorks mutexes.])AH_TEMPLATE(HAVE_MUTEX_WIN32, [Define to 1 to use Windows mutexes.])AC_CACHE_CHECK([for mutexes], db_cv_mutex, [db_cv_mutex=noorig_libs=$LIBS# User-specified POSIX or UI mutexes.## There are two different reasons to specify mutexes: First, the application# is already using one type of mutex and doesn't want to mix-and-match (for# example, on Solaris, which has POSIX, UI and LWP mutexes).  Second, the# applications POSIX pthreads mutexes don't support inter-process locking,# but the application wants to use them anyway (for example, current Linux# and *BSD systems).## If we're on Solaris, we insist that -lthread or -lpthread be used.  The# problem is the Solaris C library has UI/POSIX interface stubs, but they're# broken, configuring them for inter-process mutexes doesn't return an error,# but it doesn't work either.   Otherwise, we try first without the library# and then with it: there's some information that SCO/UnixWare/OpenUNIX needs# this. [#4950]## Test for LWP threads before testing for UI/POSIX threads, we prefer them# on Solaris.  There's a bug in SunOS 5.7 where applications get pwrite, not# pwrite64, if they load the C library before the appropriate threads library,# e.g., tclsh using dlopen to load the DB library.  By using LWP threads we# avoid answering lots of user questions, not to mention the bugs.if test "$db_cv_posixmutexes" = yes; then	case "$host_os" in	solaris*)		db_cv_mutex="posix_library_only";;	*)		db_cv_mutex="posix_only";;	esacfiif test "$db_cv_uimutexes" = yes; then	case "$host_os" in	solaris*)		db_cv_mutex="ui_library_only";;	*)		db_cv_mutex="ui_only";;	esacfi# LWP threads: _lwp_XXXif test "$db_cv_mutex" = no; thenAC_TRY_LINK([#include <synch.h>],[	static lwp_mutex_t mi = SHAREDMUTEX;	static lwp_cond_t ci = SHAREDCV;	lwp_mutex_t mutex = mi;	lwp_cond_t cond = ci;	exit (	_lwp_mutex_lock(&mutex) ||	_lwp_mutex_unlock(&mutex));], [db_cv_mutex="Solaris/lwp"])fi# UI threads: thr_XXX## Try with and without the -lthread library.if test "$db_cv_mutex" = no -o "$db_cv_mutex" = "ui_only"; thenAC_TRY_LINK([#include <thread.h>#include <synch.h>],[	mutex_t mutex;	cond_t cond;	int type = USYNC_PROCESS;	exit (	mutex_init(&mutex, type, NULL) ||	cond_init(&cond, type, NULL) ||	mutex_lock(&mutex) ||	mutex_unlock(&mutex));], [db_cv_mutex="UI/threads"])fiif test "$db_cv_mutex" = no -o \    "$db_cv_mutex" = "ui_only" -o "$db_cv_mutex" = "ui_library_only"; thenLIBS="$LIBS -lthread"AC_TRY_LINK([#include <thread.h>#include <synch.h>],[	mutex_t mutex;	cond_t cond;	int type = USYNC_PROCESS;	exit (	mutex_init(&mutex, type, NULL) ||	cond_init(&cond, type, NULL) ||	mutex_lock(&mutex) ||	mutex_unlock(&mutex));], [db_cv_mutex="UI/threads/library"])LIBS="$orig_libs"fiif test "$db_cv_mutex" = "ui_only" -o "$db_cv_mutex" = "ui_library_only"; then	AC_MSG_ERROR([unable to find UI mutex interfaces])fi# POSIX.1 pthreads: pthread_XXX## Try with and without the -lpthread library.  If the user specified we use# POSIX pthreads mutexes, and we fail to find the full interface, try and# configure for just intra-process support.if test "$db_cv_mutex" = no -o "$db_cv_mutex" = "posix_only"; then	AM_PTHREADS_SHARED("POSIX/pthreads")fiif test "$db_cv_mutex" = no -o \    "$db_cv_mutex" = "posix_only" -o "$db_cv_mutex" = "posix_library_only"; then	LIBS="$LIBS -lpthread"	AM_PTHREADS_SHARED("POSIX/pthreads/library")	LIBS="$orig_libs"fiif test "$db_cv_mutex" = "posix_only"; then	AM_PTHREADS_PRIVATE("POSIX/pthreads/private")fiif test "$db_cv_mutex" = "posix_only" -o \    "$db_cv_mutex" = "posix_library_only"; then	LIBS="$LIBS -lpthread"	AM_PTHREADS_PRIVATE("POSIX/pthreads/library/private")	LIBS="$orig_libs"fiif test "$db_cv_mutex" = "posix_only" -o \    "$db_cv_mutex" = "posix_library_only"; then	AC_MSG_ERROR([unable to find POSIX 1003.1 mutex interfaces])fi# msemaphore: HPPA only# Try HPPA before general msem test, it needs special alignment.if test "$db_cv_mutex" = no; thenAC_TRY_LINK([#include <sys/mman.h>],[#if defined(__hppa)	typedef msemaphore tsl_t;	msemaphore x;	msem_init(&x, 0);	msem_lock(&x, 0);	msem_unlock(&x, 0);	exit(0);#else	FAIL TO COMPILE/LINK#endif], [db_cv_mutex="HP/msem_init"])fi# msemaphore: AIX, OSF/1if test "$db_cv_mutex" = no; thenAC_TRY_LINK([#include <sys/types.h>#include <sys/mman.h>],[	typedef msemaphore tsl_t;	msemaphore x;	msem_init(&x, 0);	msem_lock(&x, 0);	msem_unlock(&x, 0);	exit(0);], [db_cv_mutex="UNIX/msem_init"])fi# ReliantUNIXif test "$db_cv_mutex" = no; thenLIBS="$LIBS -lmproc"AC_TRY_LINK([#include <ulocks.h>],[	typedef spinlock_t tsl_t;	spinlock_t x;	initspin(&x, 1);	cspinlock(&x);	spinunlock(&x);], [db_cv_mutex="ReliantUNIX/initspin"])LIBS="$orig_libs"fi# SCO: UnixWare has threads in libthread, but OpenServer doesn't.if test "$db_cv_mutex" = no; thenAC_TRY_COMPILE(,[#if defined(__USLC__)	exit(0);#else	FAIL TO COMPILE/LINK#endif], [db_cv_mutex="SCO/x86/cc-assembly"])fi# abilock_t: SGIif test "$db_cv_mutex" = no; thenAC_TRY_LINK([#include <abi_mutex.h>],[	typedef abilock_t tsl_t;	abilock_t x;	init_lock(&x);	acquire_lock(&x);	release_lock(&x);], [db_cv_mutex="SGI/init_lock"])fi# sema_t: Solaris# The sema_XXX calls do not work on Solaris 5.5.  I see no reason to ever# turn this test on, unless we find some other platform that uses the old# POSIX.1 interfaces.  (I plan to move directly to pthreads on Solaris.)if test "$db_cv_mutex" = DOESNT_WORK; thenAC_TRY_LINK([#include <synch.h>],[	typedef sema_t tsl_t;	sema_t x;	sema_init(&x, 1, USYNC_PROCESS, NULL);	sema_wait(&x);	sema_post(&x);], [db_cv_mutex="UNIX/sema_init"])fi# _lock_try/_lock_clear: Solaris# On Solaris systems without Pthread or UI mutex interfaces, DB uses the