Libc-763.11.tar.gz

[apple/libc.git] / threads / mig_support.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1989 Carnegie-Mellon University
 * All rights reserved.  The CMU software License Agreement specifies
 * the terms and conditions for use and redistribution.
 */
/*
 * mig_support.c  - by Mary Thompson
 *
 * Routines to set and deallocate the mig reply port for the current thread.
 * Called from mig-generated interfaces.
 */
#include <mach/mach.h>
#include <pthread_internals.h>
#include <pthread.h>

#include "cthreads.h"
#include "cthread_internals.h"

pthread_lock_t reply_port_lock;
extern mach_port_t _pthread_reply_port(pthread_t);
static mach_port_t _task_reply_port = MACH_PORT_NULL;

/*
 * called in new child...
 * clear lock to cover case where the parent had
 * a thread holding this lock while another thread
 * did the fork()
 */
void mig_fork_child()
{
	UNLOCK(reply_port_lock);
}

/*
 * Called by mach_init with 0 before cthread_init is
 * called and again with 1 at the end of cthread_init.
 */
void
mig_init(init_done)
	int init_done;
{
    if (init_done == 0) {
        LOCK_INIT(reply_port_lock);
        _task_reply_port = mach_reply_port();
    }
}

/*
 * Called by mig interface code whenever a reply port is needed.
 * Tracing is masked during this call; otherwise, a call to printf()
 * can result in a call to malloc() which eventually reenters
 * mig_get_reply_port() and deadlocks.
 */
mach_port_t _mig_get_reply_port()
{
    pthread_t pself;

    pself = pthread_self();
    if ((pself != (pthread_t)NULL) && (pself->sig == _PTHREAD_SIG)) {
        return pself->reply_port;
    }
    return MACH_PORT_NULL;
}

void _mig_set_reply_port(mach_port_t port)
{
    pthread_t pself;
    pself = pthread_self();
    
    if ((pself != (pthread_t)NULL) && (pself->sig == _PTHREAD_SIG)) {
        pself->reply_port = port;
    }
}