source: python/trunk/Python/thread_lwp.h@ 384

#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 initially */

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


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

/*
 * Thread support.
 */


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

long PyThread_get_thread_ident(void)
{
        thread_t tid;
        if (!initialized)
                PyThread_init_thread();
        if (lwp_self(&tid) < 0)
                return -1;
        return tid.thread_id;
}

static void do_PyThread_exit_thread(int no_cleanup)
{
        dprintf(("PyThread_exit_thread called\n"));
        if (!initialized)
                if (no_cleanup)
                        _exit(0);
                else
                        exit(0);
        lwp_destroy(SELF);
}

void PyThread_exit_thread(void)
{
        do_PyThread_exit_thread(0);
}

void 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);
                else
                        exit(status);
        pod_exit(status);
}

void PyThread_exit_prog(int status)
{
        do_PyThread_exit_prog(status, 0);
}

void PyThread__exit_prog(int status)
{
        do_PyThread_exit_prog(status, 1);
}
#endif /* NO_EXIT_PROG */

/*
 * Lock support.
 */
PyThread_type_lock PyThread_allocate_lock(void)
{
        struct lock *lock;
        extern char *malloc(size_t);

        dprintf(("PyThread_allocate_lock called\n"));
        if (!initialized)
                PyThread_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(("PyThread_allocate_lock() -> %p\n", lock));
        return (PyThread_type_lock) lock;
}

void PyThread_free_lock(PyThread_type_lock lock)
{
        dprintf(("PyThread_free_lock(%p) called\n", lock));
        mon_destroy(((struct lock *) lock)->lock_monitor);
        free((char *) lock);
}

int PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
{
        int success;

        dprintf(("PyThread_acquire_lock(%p, %d) called\n", 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(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
        return success;
}

void PyThread_release_lock(PyThread_type_lock lock)
{
        dprintf(("PyThread_release_lock(%p) called\n", 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);
}