-/* $Id: rsmultiandor.c,v 1.1 2004-09-28 13:06:35 heikki Exp $
+/* $Id: rsmultiandor.c,v 1.2 2004-09-28 16:12:42 heikki Exp $
Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002
Index Data Aps
struct rset_multiandor_rfd {
int flag;
struct heap_item *items; /* we alloc and free them here */
- HEAP h;
+ HEAP h; /* and move around here */
zint hits; /* returned so far */
int eof; /* seen the end of it */
+ int tailcount; /* how many items are tailing */
+ char *tailbits;
};
/* Heap functions ***********************/
/* nothing to delete, all is nmem'd, and will go away in due time */
}
+int compare_ands(const void *x, const void *y)
+{ /* used in qsort to get the multi-and args in optimal order */
+ /* that is, those with fewest occurrences first */
+ const struct heap_item *hx=x;
+ const struct heap_item *hy=y;
+ double cur, totx, toty;
+ rset_pos(hx->fd, &cur, &totx);
+ rset_pos(hy->fd, &cur, &toty);
+ if ( totx > toty +0.5 ) return 1;
+ if ( totx < toty -0.5 ) return -1;
+ return 0; /* return totx - toty, except for overflows and rounding */
+}
/* Creating and deleting rsets ***********************/
rset_delete(info->rsets[i]);
}
+
/* Opening and closing fd's on them *********************/
static RSFD r_open_andor (RSET ct, int flag, int is_and)
rfd=rfd_create_base(ct);
if (rfd->priv) {
p=(struct rset_multiandor_rfd *)rfd->priv;
- heap_clear(p->h);
+ if (!is_and)
+ heap_clear(p->h);
assert(p->items);
/* all other pointers shouls already be allocated, in right sizes! */
}
else {
p = (struct rset_multiandor_rfd *) nmem_malloc (ct->nmem,sizeof(*p));
rfd->priv=p;
- p->h = heap_create( ct->nmem, info->no_rsets, kctrl);
+ p->h=0;
+ p->tailbits=0;
+ if (is_and)
+ p->tailbits=nmem_malloc(ct->nmem, info->no_rsets*sizeof(char) );
+ else
+ p->h = heap_create( ct->nmem, info->no_rsets, kctrl);
p->items=(struct heap_item *) nmem_malloc(ct->nmem,
info->no_rsets*sizeof(*p->items));
for (i=0; i<info->no_rsets; i++){
p->flag = flag;
p->hits=0;
p->eof=0;
+ p->tailcount=0;
if (is_and)
{ /* read the array and sort it */
for (i=0; i<info->no_rsets; i++){
p->items[i].fd=rset_open(info->rsets[i],RSETF_READ);
if ( !rset_read(p->items[i].fd, p->items[i].buf) )
p->eof=1;
+ p->tailbits[i]=0;
}
+ qsort(p->items, info->no_rsets, sizeof(p->items[0]), compare_ands);
} else
{ /* fill the heap for ORing */
for (i=0; i<info->no_rsets; i++){
static void r_close (RSFD rfd)
{
- struct rset_multiandor_info *info=(struct rset_multiandor_info *)(rfd->rset->priv);
+ struct rset_multiandor_info *info=
+ (struct rset_multiandor_info *)(rfd->rset->priv);
struct rset_multiandor_rfd *p=(struct rset_multiandor_rfd *)(rfd->priv);
int i;
- heap_destroy (p->h);
+ if (p->h)
+ heap_destroy (p->h);
for (i = 0; i<info->no_rsets; i++)
if (p->items[i].fd)
rset_close(p->items[i].fd);
}
static int r_read_and (RSFD rfd, void *buf)
-{
- return 0;
+{ /* Has to return all hits where each item points to the */
+ /* same sysno (scope), in order. Keep an extra key (hitkey) */
+ /* as long as all records do not point to hitkey, forward */
+ /* them, and update hitkey to be the highest seen so far. */
+ /* (if any item eof's, mark eof, and return 0 thereafter) */
+ /* Once a hit has been found, scan all items for the smallest */
+ /* value. Mark all as being in the tail. Read next from that */
+ /* item, and if not in the same record, clear its tail bit */
+ struct rset_multiandor_rfd *p=rfd->priv;
+ const struct key_control *kctrl=rfd->rset->keycontrol;
+ struct rset_multiandor_info *info=rfd->rset->priv;
+ int i, mintail;
+ int cmp;
+
+ while (1) {
+ if (p->tailcount)
+ { /* we are tailing, find lowest tail and return it */
+ mintail=0;
+ while ((mintail<info->no_rsets) && !p->tailbits[mintail])
+ mintail++; /* first tail */
+ for (i=mintail+1;i<info->no_rsets;i++)
+ {
+ if (p->tailbits[i])
+ {
+ cmp=(*kctrl->cmp)(p->items[i].buf,p->items[mintail].buf);
+ if (cmp<0)
+ mintail=i;
+ }
+ }
+ /* return the lowest tail */
+ memcpy(buf, p->items[mintail].buf, kctrl->key_size);
+ if (!rset_read(p->items[mintail].fd, p->items[mintail].buf))
+ {
+ p->eof=1; /* game over, once tails have been returned */
+ p->tailbits[mintail]=0;
+ (p->tailcount)--;
+ return 1;
+ }
+ /* still a tail? */
+ cmp=(*kctrl->cmp)(p->items[mintail].buf,buf);
+ if (cmp >= rfd->rset->scope){
+ p->tailbits[mintail]=0;
+ (p->tailcount)--;
+ }
+ return 1;
+ }
+ /* not tailing, forward until all reocrds match, and set up */
+ /* as tails. the earlier 'if' will then return the hits */
+ if (p->eof)
+ return 0; /* nothing more to see */
+ i=1; /* assume items[0] is highest up */
+ while (i<info->no_rsets) {
+ cmp=(*kctrl->cmp)(p->items[0].buf,p->items[i].buf);
+ if (cmp<=-rfd->rset->scope) { /* [0] was behind, forward it */
+ if (!rset_forward(p->items[0].fd, p->items[0].buf,
+ p->items[i].buf))
+ {
+ p->eof=1; /* game over */
+ return 0;
+ }
+ i=0; /* start frowarding from scratch */
+ } else if (cmp>=rfd->rset->scope)
+ { /* [0] was ahead, forward i */
+ if (!rset_forward(p->items[i].fd, p->items[i].buf,
+ p->items[0].buf))
+ {
+ p->eof=1; /* game over */
+ return 0;
+ }
+ } else
+ i++;
+ } /* while i */
+ /* if we get this far, all rsets are now within +- scope of [0] */
+ /* ergo, we have a hit. Mark them all as tailing, and let the */
+ /* upper 'if' return the hits in right order */
+ for (i=0; i<info->no_rsets;i++)
+ p->tailbits[i]=1;
+ p->tailcount=info->no_rsets;
+ } /* while 1 */
}
+
+
static int r_forward_and(RSFD rfd, void *buf, const void *untilbuf)
{
return 0;
int i;
for (i=0; i<info->no_rsets; i++){
rset_pos(mrfd->items[i].fd, &cur, &tot);
- logf(LOG_LOG, "r_pos: %d %0.1f %0.1f", i, cur,tot);
+ logf(LOG_DEBUG, "r_pos: %d %0.1f %0.1f", i, cur,tot);
scur += cur;
stot += tot;
}