cpython/Python/thread_lwp.h

/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI or Corporation for National Research Initiatives or
CNRI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior
permission.

While CWI is the initial source for this software, a modified version
is made available by the Corporation for National Research Initiatives
(CNRI) at the Internet address ftp://ftp.python.org.

STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

#include <stdlib.h>
#include <lwp/lwp.h>
#include <lwp/stackdep.h>

#define STACKSIZE	1000	/* stacksize for a thread */
#define NSTACKS		2	/* # stacks to be put in cache initialy */

struct lock {
	int lock_locked;
	cv_t lock_condvar;
	mon_t lock_monitor;
};


/*
 * Initialization.
 */
static void _init_thread _P0()
{
	lwp_setstkcache(STACKSIZE, NSTACKS);
}

/*
 * Thread support.
 */


int start_new_thread _P2(func, void (*func) _P((void *)), arg, void *arg)
{
	thread_t tid;
	int success;
	dprintf(("start_new_thread called\n"));
	if (!initialized)
		init_thread();
	success = lwp_create(&tid, func, MINPRIO, 0, lwp_newstk(), 1, arg);
	return success < 0 ? 0 : 1;
}

long get_thread_ident _P0()
{
	thread_t tid;
	if (!initialized)
		init_thread();
	if (lwp_self(&tid) < 0)
		return -1;
	return tid.thread_id;
}

static void do_exit_thread _P1(no_cleanup, int no_cleanup)
{
	dprintf(("exit_thread called\n"));
	if (!initialized)
		if (no_cleanup)
			_exit(0);
		else
			exit(0);
	lwp_destroy(SELF);
}

void exit_thread _P0()
{
	do_exit_thread(0);
}

void _exit_thread _P0()
{
	do_exit_thread(1);
}

#ifndef NO_EXIT_PROG
static void do_exit_prog _P2(status, int status, no_cleanup, int no_cleanup)
{
	dprintf(("exit_prog(%d) called\n", status));
	if (!initialized)
		if (no_cleanup)
			_exit(status);
		else
			exit(status);
	pod_exit(status);
}

void exit_prog _P1(status, int status)
{
	do_exit_prog(status, 0);
}

void _exit_prog _P1(status, int status)
{
	do_exit_prog(status, 1);
}
#endif /* NO_EXIT_PROG */

/*
 * Lock support.
 */
type_lock allocate_lock _P0()
{
	struct lock *lock;
	extern char *malloc();

	dprintf(("allocate_lock called\n"));
	if (!initialized)
		init_thread();

	lock = (struct lock *) malloc(sizeof(struct lock));
	lock->lock_locked = 0;
	(void) mon_create(&lock->lock_monitor);
	(void) cv_create(&lock->lock_condvar, lock->lock_monitor);
	dprintf(("allocate_lock() -> %lx\n", (long)lock));
	return (type_lock) lock;
}

void free_lock _P1(lock, type_lock lock)
{
	dprintf(("free_lock(%lx) called\n", (long)lock));
	mon_destroy(((struct lock *) lock)->lock_monitor);
	free((char *) lock);
}

int acquire_lock _P2(lock, type_lock lock, waitflag, int waitflag)
{
	int success;

	dprintf(("acquire_lock(%lx, %d) called\n", (long)lock, waitflag));
	success = 0;

	(void) mon_enter(((struct lock *) lock)->lock_monitor);
	if (waitflag)
		while (((struct lock *) lock)->lock_locked)
			cv_wait(((struct lock *) lock)->lock_condvar);
	if (!((struct lock *) lock)->lock_locked) {
		success = 1;
		((struct lock *) lock)->lock_locked = 1;
	}
	cv_broadcast(((struct lock *) lock)->lock_condvar);
	mon_exit(((struct lock *) lock)->lock_monitor);
	dprintf(("acquire_lock(%lx, %d) -> %d\n", (long)lock, waitflag, success));
	return success;
}

void release_lock _P1(lock, type_lock lock)
{
	dprintf(("release_lock(%lx) called\n", (long)lock));
	(void) mon_enter(((struct lock *) lock)->lock_monitor);
	((struct lock *) lock)->lock_locked = 0;
	cv_broadcast(((struct lock *) lock)->lock_condvar);
	mon_exit(((struct lock *) lock)->lock_monitor);
}

/*
 * Semaphore support.
 */
type_sema allocate_sema _P1(value, int value)
{
	type_sema sema = 0;
	dprintf(("allocate_sema called\n"));
	if (!initialized)
		init_thread();

	dprintf(("allocate_sema() -> %lx\n", (long) sema));
	return (type_sema) sema;
}

void free_sema _P1(sema, type_sema sema)
{
	dprintf(("free_sema(%lx) called\n", (long) sema));
}

int down_sema _P2(sema, type_sema sema, waitflag, int waitflag)
{
	dprintf(("down_sema(%lx, %d) called\n", (long) sema, waitflag));
	dprintf(("down_sema(%lx) return\n", (long) sema));
	return -1;
}

void up_sema _P1(sema, type_sema sema)
{
	dprintf(("up_sema(%lx)\n", (long) sema));
}