shithub: riscv

ref: 7effba9d98e8a39ee1504192d02d40e86d90b19a
dir: /sys/src/cmd/gs/src/gp_nsync.c/

/* Copyright (C) 1998, 1999 Aladdin Enterprises.  All rights reserved.
  
  This software is provided AS-IS with no warranty, either express or
  implied.
  
  This software is distributed under license and may not be copied,
  modified or distributed except as expressly authorized under the terms
  of the license contained in the file LICENSE in this distribution.
  
  For more information about licensing, please refer to
  http://www.ghostscript.com/licensing/. For information on
  commercial licensing, go to http://www.artifex.com/licensing/ or
  contact Artifex Software, Inc., 101 Lucas Valley Road #110,
  San Rafael, CA  94903, U.S.A., +1(415)492-9861.
*/

/* $Id: gp_nsync.c,v 1.4 2002/02/21 22:24:52 giles Exp $ */
/* Dummy thread / semaphore / monitor implementation */
#include "std.h"
#include "gserror.h"
#include "gserrors.h"
#include "gpsync.h"

/* ------- Synchronization primitives -------- */

/* Semaphores */

uint
gp_semaphore_sizeof(void)
{
    return sizeof(gp_semaphore);
}

int
gp_semaphore_open(gp_semaphore * sema)
{
    if (sema)
	*(int *)sema = 0;
    return 0;
}

int
gp_semaphore_close(gp_semaphore * sema)
{
    return 0;
}

int
gp_semaphore_wait(gp_semaphore * sema)
{
    if (*(int *)sema == 0)
	return_error(gs_error_unknownerror); /* no real waiting */
    --(*(int *)sema);
    return 0;
}

int
gp_semaphore_signal(gp_semaphore * sema)
{
    ++(*(int *)sema);
    return 0;
}

/* Monitors */

uint
gp_monitor_sizeof(void)
{
    return sizeof(gp_monitor);
}

int
gp_monitor_open(gp_monitor * mon)
{
    if (mon)
	mon->dummy_ = 0;
    return 0;
}

int
gp_monitor_close(gp_monitor * mon)
{
    return 0;
}

int
gp_monitor_enter(gp_monitor * mon)
{
    if (mon->dummy_ != 0)
	return_error(gs_error_unknownerror);
    mon->dummy_ = mon;
    return 0;
}

int
gp_monitor_leave(gp_monitor * mon)
{
    if (mon->dummy_ != mon)
	return_error(gs_error_unknownerror);
    mon->dummy_ = 0;
    return 0;
}

/* Thread creation */

int
gp_create_thread(gp_thread_creation_callback_t proc, void *proc_data)
{
    return_error(gs_error_unknownerror);
}