2.11BSD/ingres/source/iutil/pglocks.c

# include	"../ingres.h"
# include	"../access.h"
# include	"../lock.h"

struct lockreq	Lock;
/*
 *	setpgl- sets a lock for the access buffer
 */
setpgl(buf)
struct	accbuf	*buf;
{
	register struct accbuf	*b;
	register int		i;

#	ifdef xATR1
	if (tTf(98,  2))
	{
		printf(" setpgl r=%s ", locv(buf->rel_tupid));
		printf("p=%s \n", locv(buf->thispage));
	}
#	endif
	if (Alockdes < 0)
		return(1);
	b = buf;
	Lock.lract = A_SLP;	/* wait for lock */
	Lock.lrtype = T_PAGE;	/* page lock */
	Lock.lrmod = M_EXCL;	/* exclusive lock */
	bmove(&b->rel_tupid, Lock.lrel, 4);	/* copy relation id */
	bmove(&b->thispage, Lock.lpage, 4);	/* copy page id */
	i = write(Alockdes,  &Lock,  sizeof(struct lockreq));
	b->bufstatus |= BUF_LOCKED;
	return(i);
}
/*
 *	unlpg- releases a page lock
 */
unlpg(buf)
struct	accbuf	*buf;
{
	register struct	accbuf	*b;
	register int		i;

#	ifdef xATR1
	if (tTf(98,  3))
	{
		printf(" unlpg r=%s ", locv(buf->rel_tupid));
		printf("p=%s \n", locv(buf->thispage));
	}
#	endif
	if (Alockdes < 0)
		return(1);
	b = buf;
	Lock.lract = A_RLS1;
	bmove(&b->rel_tupid, Lock.lrel, 4);	/* copy relation id */
	Lock.lrtype = T_PAGE;	/* page lock */
	bmove(&b->thispage, Lock.lpage, 4);	/* copy page id */
	b->bufstatus &= ~BUF_LOCKED;
	i = write(Alockdes,  &Lock,  sizeof(struct lockreq));
	return(i);
}
/*
 *	unlall - release all locks held by this process
 */
unlall()
{
	register int	i;


#	ifdef xATR1
	if (tTf(98,  6))
		printf(" unlall \n");
#	endif

	Acclock = TRUE;	/* reset page lock flag just in case */
	if (Alockdes < 0)
		return(1);
	Lock.lract = A_RLSA;
	i = write(Alockdes, &Lock, sizeof(struct lockreq));
	return (i);
}