/* Copyright (C) 1998 Aladdin Enterprises.  All rights reserved.

   This file is part of Aladdin Ghostscript.

   Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
   or distributor accepts any responsibility for the consequences of using it,
   or for whether it serves any particular purpose or works at all, unless he
   or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
   License (the "License") for full details.

   Every copy of Aladdin Ghostscript must include a copy of the License,
   normally in a plain ASCII text file named PUBLIC.  The License grants you
   the right to copy, modify and redistribute Aladdin Ghostscript, but only
   under certain conditions described in the License.  Among other things, the
   License requires that the copyright notice and this notice be preserved on
   all copies.
 */

/*$Id: gxsync.h $ */
/* Interface to synchronization primitives */

/* Initial version 2/1/98 by John Desrosiers (soho@crl.com) */

#if !defined(gxsync_INCLUDED)
#  define gxsync_INCLUDED

#include "gpsync.h"
#include "gsmemory.h"

/* This module abstracts the platform-specific synchronization primitives. */
/* Since these routines will see heavy use, performance is important. */

/* ----- Semaphore interface ----- */
/* These have the usual queued, counting semaphore semantics: at init time, */
/* the event count is set to 0 ('wait' will wait until 1st signal). */
typedef struct gx_semaphore_s {
    gs_memory_t *memory;	/* allocator to free memory */
    gp_semaphore native;	/* MUST BE LAST last since length is undef'd */
    /*  platform-dep impl, len is gp_semaphore_sizeof() */
} gx_semaphore_t;

gx_semaphore_t *		/* returns a new semaphore, 0 if error */
    gx_semaphore_alloc(P1(
			  gs_memory_t * memory	/* memory allocator to use */
			  ));
void
    gx_semaphore_free(P1(
			 gx_semaphore_t * sema	/* semaphore to delete */
			 ));

#define gx_semaphore_wait(sema)  gp_semaphore_wait(&(sema)->native)
#define gx_semaphore_signal(sema)  gp_semaphore_signal(&(sema)->native)


/* ----- Monitor interface ----- */
/* These have the usual monitor semantics: at init time, */
/* the event count is set to 1 (1st 'enter' succeeds immediately). */
typedef struct gx_monitor_s {
    gs_memory_t *memory;	/* allocator to free memory */
    gp_monitor native;		/* platform-dep impl, len is gp_monitor_sizeof() */
} gx_monitor_t;

gx_monitor_t *			/* returns a new monitor, 0 if error */
    gx_monitor_alloc(P1(
			gs_memory_t * memory	/* memory allocator to use */
			));
void
    gx_monitor_free(P1(
		       gx_monitor_t * mon	/* monitor to delete */
		       ));

#define gx_monitor_enter(sema)  gp_monitor_enter(&(sema)->native)
#define gx_monitor_leave(sema)  gp_monitor_leave(&(sema)->native)

#endif /* !defined(gxsync_INCLUDED) */
