/* This file is part of the Zebra server.
Copyright (C) 1994-2011 Index Data
Zebra is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
/* rsbetween is (mostly) used for xml searches. It returns the hits of the
* "middle" rset, that are in between the "left" and "right" rsets. For
* example "Shakespeare" in between "" and . The thing is
* complicated by the inclusion of attributes (from their own rset). If attrs
* specified, they must match the "left" rset (start tag). "Hamlet" between
* "
" and "". (This assumes that the attributes are
* indexed to the same seqno as the tags).
*
*/
#if HAVE_CONFIG_H
#include
#endif
#include
#include
#include
#include
#include
#include
static RSFD r_open(RSET ct, int flag);
static void r_close(RSFD rfd);
static void r_delete(RSET ct);
static int r_forward(RSFD rfd, void *buf,
TERMID *term, const void *untilbuf);
static int r_read(RSFD rfd, void *buf, TERMID *term );
static int r_write(RSFD rfd, const void *buf);
static void r_pos(RSFD rfd, double *current, double *total);
static void r_get_terms(RSET ct, TERMID *terms, int maxterms, int *curterm);
static const struct rset_control control =
{
"between",
r_delete,
r_get_terms,
r_open,
r_close,
r_forward,
r_pos,
r_read,
r_write,
};
#define STARTTAG 0
#define HIT 1
#define STOPTAG 2
#define ATTRTAG 3
struct rset_between_info {
TERMID startterm; /* pseudo terms for detecting which one we read from */
TERMID stopterm;
TERMID attrterm;
};
struct rset_between_rfd {
RSFD andrfd;
void *recbuf; /* a key that tells which record we are in */
void *startbuf; /* the start tag */
int startbufok; /* we have seen the first start tag */
void *attrbuf; /* the attr tag. If these two match, we have attr match */
int attrbufok; /* we have seen the first attr tag, can compare */
int depth; /* number of start-tags without end-tags */
int attrdepth; /* on what depth the attr matched */
zint hits;
};
static int log_level = 0;
static int log_level_initialized = 0;
/* make sure that the rset has a term attached. If not, create one */
/* we need these terms for the tags, to distinguish what we read */
static void checkterm(RSET rs, char *tag, NMEM nmem)
{
if (!rs->term)
{
rs->term = rset_term_create(tag, -1, "", 0, nmem, 0, 0, 0, 0);
rs->term->rset = rs;
}
}
RSET rset_create_between(NMEM nmem, struct rset_key_control *kcontrol,
int scope,
RSET rset_l, RSET rset_m, RSET rset_r, RSET rset_attr)
{
RSET rnew = rset_create_base(&control, nmem, kcontrol, scope, 0, 0, 0);
struct rset_between_info *info=
(struct rset_between_info *) nmem_malloc(rnew->nmem,sizeof(*info));
RSET rsetarray[4];
int n = 4;
if (!log_level_initialized)
{
log_level = yaz_log_module_level("rsbetween");
log_level_initialized = 1;
}
rsetarray[STARTTAG] = rset_l;
rsetarray[HIT] = rset_m;
rsetarray[STOPTAG] = rset_r;
rsetarray[ATTRTAG] = rset_attr;
/* make sure we have decent terms for all rsets. Create dummies if needed*/
checkterm(rsetarray[STARTTAG], "(start)", nmem);
checkterm(rsetarray[STOPTAG], "(start)", nmem);
info->startterm = rsetarray[STARTTAG]->term;
info->stopterm = rsetarray[STOPTAG]->term;
if (rset_attr)
{
checkterm(rsetarray[ATTRTAG], "(start)", nmem);
info->attrterm = rsetarray[ATTRTAG]->term;
n = 4;
}
else
{
info->attrterm = NULL;
n = 3;
}
rnew->no_children = 1;
rnew->children = nmem_malloc(rnew->nmem, sizeof(RSET *));
rnew->children[0] = rset_create_and(nmem, kcontrol,
scope, n, rsetarray);
rnew->priv = info;
yaz_log(log_level, "create rset at %p", rnew);
return rnew;
}
static void r_delete(RSET ct)
{
}
static RSFD r_open(RSET ct, int flag)
{
RSFD rfd;
struct rset_between_rfd *p;
if (flag & RSETF_WRITE)
{
yaz_log(YLOG_FATAL, "between set type is read-only");
return NULL;
}
rfd = rfd_create_base(ct);
if (rfd->priv)
p=(struct rset_between_rfd *)rfd->priv;
else {
p = (struct rset_between_rfd *) nmem_malloc(ct->nmem, (sizeof(*p)));
rfd->priv = p;
p->recbuf = nmem_malloc(ct->nmem, ct->keycontrol->key_size);
p->startbuf = nmem_malloc(ct->nmem, ct->keycontrol->key_size);
p->attrbuf = nmem_malloc(ct->nmem, ct->keycontrol->key_size);
}
p->andrfd = rset_open(ct->children[0], RSETF_READ);
p->hits = -1;
p->depth = 0;
p->attrdepth = 0;
p->attrbufok = 0;
p->startbufok = 0;
yaz_log(log_level, "open rset=%p rfd=%p", ct, rfd);
return rfd;
}
static void r_close(RSFD rfd)
{
struct rset_between_rfd *p=(struct rset_between_rfd *)rfd->priv;
yaz_log(log_level,"close rfd=%p", rfd);
rset_close(p->andrfd);
}
static int r_forward(RSFD rfd, void *buf,
TERMID *term, const void *untilbuf)
{
struct rset_between_rfd *p=(struct rset_between_rfd *)rfd->priv;
int rc;
yaz_log(log_level, "forwarding ");
rc = rset_forward(p->andrfd,buf,term,untilbuf);
return rc;
}
static void checkattr(RSFD rfd)
{
struct rset_between_info *info =(struct rset_between_info *)
rfd->rset->priv;
struct rset_between_rfd *p = (struct rset_between_rfd *)rfd->priv;
const struct rset_key_control *kctrl = rfd->rset->keycontrol;
int cmp;
if (p->attrdepth)
return; /* already found one */
if (!info->attrterm)
{
p->attrdepth=-1; /* matches always */
return;
}
if ( p->startbufok && p->attrbufok )
{ /* have buffers to compare */
cmp=(kctrl->cmp)(p->startbuf,p->attrbuf);
if (0==cmp) /* and the keys match */
{
p->attrdepth = p->depth;
yaz_log(log_level, "found attribute match at depth %d",p->attrdepth);
}
}
}
static int r_read(RSFD rfd, void *buf, TERMID *term)
{
struct rset_between_info *info =
(struct rset_between_info *)rfd->rset->priv;
struct rset_between_rfd *p = (struct rset_between_rfd *)rfd->priv;
const struct rset_key_control *kctrl = rfd->rset->keycontrol;
int cmp;
TERMID dummyterm = 0;
yaz_log(log_level, "== read: term=%p",term);
if (!term)
term = &dummyterm;
while (rset_read(p->andrfd, buf, term))
{
yaz_log(log_level,"read loop term=%p d=%d ad=%d",
*term, p->depth, p->attrdepth);
if (p->hits<0)
{/* first time? */
memcpy(p->recbuf, buf, kctrl->key_size);
p->hits = 0;
cmp = rfd->rset->scope; /* force newrecord */
}
else {
cmp = (kctrl->cmp)(buf, p->recbuf);
yaz_log(log_level, "cmp=%d", cmp);
}
if (cmp>=rfd->rset->scope)
{
yaz_log(log_level, "new record");
p->depth = 0;
p->attrdepth = 0;
memcpy(p->recbuf, buf, kctrl->key_size);
}
if (*term)
yaz_log(log_level, " term: '%s'", (*term)->name);
if (*term==info->startterm)
{
p->depth++;
yaz_log(log_level, "read start tag. d=%d", p->depth);
memcpy(p->startbuf, buf, kctrl->key_size);
p->startbufok = 1;
checkattr(rfd); /* in case we already saw the attr here */
}
else if (*term==info->stopterm)
{
if (p->depth == p->attrdepth)
p->attrdepth = 0; /* ending the tag with attr match */
p->depth--;
yaz_log(log_level,"read end tag. d=%d ad=%d", p->depth,
p->attrdepth);
}
else if (*term==info->attrterm)
{
yaz_log(log_level,"read attr");
memcpy(p->attrbuf, buf, kctrl->key_size);
p->attrbufok = 1;
checkattr(rfd); /* in case the start tag came first */
}
else
{ /* mut be a real hit */
if (p->depth && p->attrdepth)
{
p->hits++;
yaz_log(log_level,"got a hit h="ZINT_FORMAT" d=%d ad=%d",
p->hits, p->depth, p->attrdepth);
return 1; /* we have everything in place already! */
} else
yaz_log(log_level, "Ignoring hit. h="ZINT_FORMAT" d=%d ad=%d",
p->hits, p->depth, p->attrdepth);
}
} /* while read */
return 0;
} /* r_read */
static int r_write(RSFD rfd, const void *buf)
{
yaz_log(YLOG_FATAL, "between set type is read-only");
return -1;
}
static void r_pos(RSFD rfd, double *current, double *total)
{
struct rset_between_rfd *p=(struct rset_between_rfd *)rfd->priv;
rset_pos(p->andrfd, current, total);
yaz_log(log_level, "pos: %0.1f/%0.1f ", *current, *total);
}
static void r_get_terms(RSET ct, TERMID *terms, int maxterms, int *curterm)
{
rset_getterms(ct->children[0], terms, maxterms, curterm);
}
/*
* Local variables:
* c-basic-offset: 4
* c-file-style: "Stroustrup"
* indent-tabs-mode: nil
* End:
* vim: shiftwidth=4 tabstop=8 expandtab
*/