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/* Posix threads interface */
#include <stdlib.h>
#include <string.h>
#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
#define destructor xxdestructor
#include <pthread.h>
#if defined(__APPLE__) || defined(HAVE_PTHREAD_DESTRUCTOR)
#undef destructor
#include <signal.h>
/* The POSIX spec requires that use of pthread_attr_setstacksize
   be conditional on _POSIX_THREAD_ATTR_STACKSIZE being defined. */
#ifdef _POSIX_THREAD_ATTR_STACKSIZE
#ifndef THREAD_STACK_SIZE
#define	THREAD_STACK_SIZE	0	/* use default stack size */
/* for safety, ensure a viable minimum stacksize */
#define	THREAD_STACK_MIN	0x8000	/* 32kB */
#else  /* !_POSIX_THREAD_ATTR_STACKSIZE */
#ifdef THREAD_STACK_SIZE
#error "THREAD_STACK_SIZE defined but _POSIX_THREAD_ATTR_STACKSIZE undefined"
/* The POSIX spec says that implementations supporting the sem_*
   family of functions must indicate this by defining
   _POSIX_SEMAPHORES. */   
#ifdef _POSIX_SEMAPHORES
/* On FreeBSD 4.x, _POSIX_SEMAPHORES is defined empty, so 
   we need to add 0 to make it work there as well. */
#if (_POSIX_SEMAPHORES+0) == -1
#define HAVE_BROKEN_POSIX_SEMAPHORES
#include <semaphore.h>
#include <errno.h>
/* Before FreeBSD 5.4, system scope threads was very limited resource
   in default setting.  So the process scope is preferred to get
   enough number of threads to work. */
#ifdef __FreeBSD__
#include <osreldate.h>
#if __FreeBSD_version >= 500000 && __FreeBSD_version < 504101
#undef PTHREAD_SYSTEM_SCHED_SUPPORTED
#if !defined(pthread_attr_default)
#  define pthread_attr_default ((pthread_attr_t *)NULL)
#if !defined(pthread_mutexattr_default)
#  define pthread_mutexattr_default ((pthread_mutexattr_t *)NULL)
#if !defined(pthread_condattr_default)
#  define pthread_condattr_default ((pthread_condattr_t *)NULL)
/* Whether or not to use semaphores directly rather than emulating them with
 * mutexes and condition variables:
#if defined(_POSIX_SEMAPHORES) && !defined(HAVE_BROKEN_POSIX_SEMAPHORES)
#  define USE_SEMAPHORES
#  undef USE_SEMAPHORES
/* On platforms that don't use standard POSIX threads pthread_sigmask()
 * isn't present.  DEC threads uses sigprocmask() instead as do most
 * other UNIX International compliant systems that don't have the full
 * pthread implementation.
#if defined(HAVE_PTHREAD_SIGMASK) && !defined(HAVE_BROKEN_PTHREAD_SIGMASK)
#  define SET_THREAD_SIGMASK pthread_sigmask
#  define SET_THREAD_SIGMASK sigprocmask
/* A pthread mutex isn't sufficient to model the Python lock type
 * because, according to Draft 5 of the docs (P1003.4a/D5), both of the
 * following are undefined:
 *  -> a thread tries to lock a mutex it already has locked
 *  -> a thread tries to unlock a mutex locked by a different thread
 * pthread mutexes are designed for serializing threads over short pieces
 * of code anyway, so wouldn't be an appropriate implementation of
 * Python's locks regardless.
 * The pthread_lock struct implements a Python lock as a "locked?" bit
 * and a <condition, mutex> pair.  In general, if the bit can be acquired
 * instantly, it is, else the pair is used to block the thread until the
 * bit is cleared.     9 May 1994 tim@ksr.com
typedef struct {
	char             locked; /* 0=unlocked, 1=locked */
	/* a <cond, mutex> pair to handle an acquire of a locked lock */
	pthread_cond_t   lock_released;
	pthread_mutex_t  mut;
} pthread_lock;
#define CHECK_STATUS(name)  if (status != 0) { perror(name); error = 1; }
 * Initialization.
#ifdef _HAVE_BSDI
void _noop(void)
static void
PyThread__init_thread(void)
	/* DO AN INIT BY STARTING THE THREAD */
	static int dummy = 0;
	pthread_t thread1;
	pthread_create(&thread1, NULL, (void *) _noop, &dummy);
	pthread_join(thread1, NULL);
#else /* !_HAVE_BSDI */
static void
PyThread__init_thread(void)
#if defined(_AIX) && defined(__GNUC__)
	pthread_init();
#endif /* !_HAVE_BSDI */
 * Thread support.
PyThread_start_new_thread(void (*func)(void *), void *arg)
	pthread_t th;
	int status;
#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
	pthread_attr_t attrs;
#if defined(THREAD_STACK_SIZE)
	size_t	tss;
	dprintf(("PyThread_start_new_thread called\n"));
	if (!initialized)
		PyThread_init_thread();
#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
	if (pthread_attr_init(&attrs) != 0)
		return -1;
#if defined(THREAD_STACK_SIZE)
	tss = (_pythread_stacksize != 0) ? _pythread_stacksize
					 : THREAD_STACK_SIZE;
	if (tss != 0) {
		if (pthread_attr_setstacksize(&attrs, tss) != 0) {
			pthread_attr_destroy(&attrs);
			return -1;
#if defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
        pthread_attr_setscope(&attrs, PTHREAD_SCOPE_SYSTEM);
	status = pthread_create(&th, 
#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
				 &attrs,
				 (pthread_attr_t*)NULL,
				 (void* (*)(void *))func,
				 (void *)arg
#if defined(THREAD_STACK_SIZE) || defined(PTHREAD_SYSTEM_SCHED_SUPPORTED)
	pthread_attr_destroy(&attrs);
	if (status != 0)
            return -1;
        pthread_detach(th);
#if SIZEOF_PTHREAD_T <= SIZEOF_LONG
	return (long) th;
	return (long) *(long *) &th;
/* XXX This implementation is considered (to quote Tim Peters) "inherently
   hosed" because:
     - It does not guarantee the promise that a non-zero integer is returned.
     - The cast to long is inherently unsafe.
     - It is not clear that the 'volatile' (for AIX?) and ugly casting in the
       latter return statement (for Alpha OSF/1) are any longer necessary.
PyThread_get_thread_ident(void)
	volatile pthread_t threadid;
	if (!initialized)
		PyThread_init_thread();
	/* Jump through some hoops for Alpha OSF/1 */
	threadid = pthread_self();
#if SIZEOF_PTHREAD_T <= SIZEOF_LONG
	return (long) threadid;
	return (long) *(long *) &threadid;
static void 
do_PyThread_exit_thread(int no_cleanup)
	dprintf(("PyThread_exit_thread called\n"));
	if (!initialized) {
		if (no_cleanup)
			_exit(0);
			exit(0);
PyThread_exit_thread(void)
	do_PyThread_exit_thread(0);
PyThread__exit_thread(void)
	do_PyThread_exit_thread(1);
#ifndef NO_EXIT_PROG
static void 
do_PyThread_exit_prog(int status, int no_cleanup)
	dprintf(("PyThread_exit_prog(%d) called\n", status));
	if (!initialized)
		if (no_cleanup)
			_exit(status);
			exit(status);
PyThread_exit_prog(int status)
	do_PyThread_exit_prog(status, 0);
PyThread__exit_prog(int status)
	do_PyThread_exit_prog(status, 1);
#endif /* NO_EXIT_PROG */
#ifdef USE_SEMAPHORES
 * Lock support.
PyThread_type_lock 
PyThread_allocate_lock(void)
	sem_t *lock;
	int status, error = 0;
	dprintf(("PyThread_allocate_lock called\n"));
	if (!initialized)
		PyThread_init_thread();
	lock = (sem_t *)malloc(sizeof(sem_t));
	if (lock) {
		status = sem_init(lock,0,1);
		CHECK_STATUS("sem_init");
		if (error) {
			free((void *)lock);
			lock = NULL;
	dprintf(("PyThread_allocate_lock() -> %p\n", lock));
	return (PyThread_type_lock)lock;
PyThread_free_lock(PyThread_type_lock lock)
	sem_t *thelock = (sem_t *)lock;
	int status, error = 0;
	dprintf(("PyThread_free_lock(%p) called\n", lock));
	if (!thelock)
	status = sem_destroy(thelock);
	CHECK_STATUS("sem_destroy");
	free((void *)thelock);
 * As of February 2002, Cygwin thread implementations mistakenly report error
 * codes in the return value of the sem_ calls (like the pthread_ functions).
 * Correct implementations return -1 and put the code in errno. This supports
fix_status(int status)
	return (status == -1) ? errno : status;
PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
	int success;
	sem_t *thelock = (sem_t *)lock;
	int status, error = 0;
	dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
		if (waitflag)
			status = fix_status(sem_wait(thelock));
			status = fix_status(sem_trywait(thelock));
	} while (status == EINTR); /* Retry if interrupted by a signal */
	if (waitflag) {
		CHECK_STATUS("sem_wait");
	} else if (status != EAGAIN) {
		CHECK_STATUS("sem_trywait");
	success = (status == 0) ? 1 : 0;
	dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
	return success;
PyThread_release_lock(PyThread_type_lock lock)
	sem_t *thelock = (sem_t *)lock;
	int status, error = 0;
	dprintf(("PyThread_release_lock(%p) called\n", lock));
	status = sem_post(thelock);
	CHECK_STATUS("sem_post");
#else /* USE_SEMAPHORES */
 * Lock support.
PyThread_type_lock 
PyThread_allocate_lock(void)
	pthread_lock *lock;
	int status, error = 0;
	dprintf(("PyThread_allocate_lock called\n"));
	if (!initialized)
		PyThread_init_thread();
	lock = (pthread_lock *) malloc(sizeof(pthread_lock));
	if (lock) {
		memset((void *)lock, '\0', sizeof(pthread_lock));
		lock->locked = 0;
		status = pthread_mutex_init(&lock->mut,
					    pthread_mutexattr_default);
		CHECK_STATUS("pthread_mutex_init");
		status = pthread_cond_init(&lock->lock_released,
					   pthread_condattr_default);
		CHECK_STATUS("pthread_cond_init");
		if (error) {
			free((void *)lock);
			lock = 0;
	dprintf(("PyThread_allocate_lock() -> %p\n", lock));
	return (PyThread_type_lock) lock;
PyThread_free_lock(PyThread_type_lock lock)
	pthread_lock *thelock = (pthread_lock *)lock;
	int status, error = 0;
	dprintf(("PyThread_free_lock(%p) called\n", lock));
	status = pthread_mutex_destroy( &thelock->mut );
	CHECK_STATUS("pthread_mutex_destroy");
	status = pthread_cond_destroy( &thelock->lock_released );
	CHECK_STATUS("pthread_cond_destroy");
	free((void *)thelock);
PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
	int success;
	pthread_lock *thelock = (pthread_lock *)lock;
	int status, error = 0;
	dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
	status = pthread_mutex_lock( &thelock->mut );
	CHECK_STATUS("pthread_mutex_lock[1]");
	success = thelock->locked == 0;
	if ( !success && waitflag ) {
		/* continue trying until we get the lock */
		/* mut must be locked by me -- part of the condition
		 * protocol */
		while ( thelock->locked ) {
			status = pthread_cond_wait(&thelock->lock_released,
						   &thelock->mut);
			CHECK_STATUS("pthread_cond_wait");
		success = 1;
	if (success) thelock->locked = 1;
	status = pthread_mutex_unlock( &thelock->mut );
	CHECK_STATUS("pthread_mutex_unlock[1]");
	if (error) success = 0;
	dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
	return success;
PyThread_release_lock(PyThread_type_lock lock)
	pthread_lock *thelock = (pthread_lock *)lock;
	int status, error = 0;
	dprintf(("PyThread_release_lock(%p) called\n", lock));
	status = pthread_mutex_lock( &thelock->mut );
	CHECK_STATUS("pthread_mutex_lock[3]");
	thelock->locked = 0;
	status = pthread_mutex_unlock( &thelock->mut );
	CHECK_STATUS("pthread_mutex_unlock[3]");
	/* wake up someone (anyone, if any) waiting on the lock */
	status = pthread_cond_signal( &thelock->lock_released );
	CHECK_STATUS("pthread_cond_signal");
#endif /* USE_SEMAPHORES */
/* set the thread stack size.
 * Return 0 if size is valid, -1 if size is invalid,
 * -2 if setting stack size is not supported.
_pythread_pthread_set_stacksize(size_t size)
#if defined(THREAD_STACK_SIZE)
	pthread_attr_t attrs;
	size_t tss_min;
	int rc = 0;
	/* set to default */
	if (size == 0) {
		_pythread_stacksize = 0;
		return 0;
#if defined(THREAD_STACK_SIZE)
#if defined(PTHREAD_STACK_MIN)
	tss_min = PTHREAD_STACK_MIN > THREAD_STACK_MIN ? PTHREAD_STACK_MIN
						       : THREAD_STACK_MIN;
	tss_min = THREAD_STACK_MIN;
	if (size >= tss_min) {
		/* validate stack size by setting thread attribute */
		if (pthread_attr_init(&attrs) == 0) {
			rc = pthread_attr_setstacksize(&attrs, size);
			pthread_attr_destroy(&attrs);
			if (rc == 0) {
				_pythread_stacksize = size;
				return 0;
	return -1;
	return -2;
#define THREAD_SET_STACKSIZE(x)	_pythread_pthread_set_stacksize(x)
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