/*
 * @RRL: 16-Oct-1997	(c) !
 */

#include	<lib$routines.h>
#include	<ssdef.h>
#include	<lckdef.h>
#include	<starlet.h>
#include	<stdio.h>
#include	<stdlib.h>
#include	<descrip.h>
#include	<string.h>
#include	<errno.h>


int	lock	(long *,int);
int	unlock	(long);

struct	lk_status_block{
	short int	cnd,
			rsv;
	int		id;
	char		val[16];
                        };

/*
 *	Input:	lkid - if lkid non zero lock function will performing lock
 *		       conversion
 *		lkmode - type of lock requested (see $LKIDEF)
 */
int	lock	(long	*lkid,int lkmode)
{
long	status;
long	tmob [ 2 ] = { -30000000, -1 };	/* delta time = 3 sec		*/
struct	lk_status_block	lksb;
$DESCRIPTOR(resnam,"RRL$RES00");	/* name of resource for       	*/
					/* SDA SHO LOCK/NAME=RRL$RESS00	*/
long	efn_blk,lkflag;
long	reqidt = 1;

	lksb.id = *lkid;
	strcpy(&lksb.val[0],"Lock Value");
	/* 
	 * call LOCK service
	 */

/*
 *	lkflag = LCK$M_VALBLK;
 */
	if (*lkid)	lkflag |= LCK$M_CONVERT;

	status = sys$enqw(0, lkmode, &lksb,
				lkflag,
				&resnam,0,0,0,0,0,0,0);

	if ( !(status & 1) )
		lib$signal(status);
	/* 
	 * check condition in Lock Status Block 
	 */
	if ( !(lksb.cnd & 1) )
		{
		status = sys$deq(lksb.id,0,0,0);
		if ( !(status & 1) )
			lib$signal(status);
		return	SS$_DEADLOCK;
		}		

	/*
	 * return LOCK ID and condition
	 */
	*lkid = lksb.id;
	return	lksb.cnd;
}

int	unlock	(long	lkid)
{
long	status;
	/*
	 * call UNLOCK
	 */
	status = sys$deq(lkid,0,0,0);
	if ( !(status & 1) )
		lib$signal(status);
	return	SS$_NORMAL;
}

void	main	(void)
{
long	status;
long	lkid = 0;

	puts("Try lock.");
	status = lock	(&lkid,LCK$K_CRMODE);

	if ( !(status & 1) )
		lib$signal(status);
	printf("\nlkid = %x",lkid);

	getchar();

	status = lock	(&lkid,LCK$K_EXMODE);

	if ( !(status & 1) )
		lib$signal(status);

	printf("\nlkid = %x",lkid);

	sys$hiber();
}