ref: 397265f5791291defa76487c2388e1898e2e433c
dir: /src/hrg/cst_relation.c/
/*************************************************************************/
/* */
/* Language Technologies Institute */
/* Carnegie Mellon University */
/* Copyright (c) 1999 */
/* All Rights Reserved. */
/* */
/* Permission is hereby granted, free of charge, to use and distribute */
/* this software and its documentation without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of this work, and to */
/* permit persons to whom this work is furnished to do so, subject to */
/* the following conditions: */
/* 1. The code must retain the above copyright notice, this list of */
/* conditions and the following disclaimer. */
/* 2. Any modifications must be clearly marked as such. */
/* 3. Original authors' names are not deleted. */
/* 4. The authors' names are not used to endorse or promote products */
/* derived from this software without specific prior written */
/* permission. */
/* */
/* CARNEGIE MELLON UNIVERSITY AND THE CONTRIBUTORS TO THIS WORK */
/* DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING */
/* ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT */
/* SHALL CARNEGIE MELLON UNIVERSITY NOR THE CONTRIBUTORS BE LIABLE */
/* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES */
/* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN */
/* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, */
/* ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF */
/* THIS SOFTWARE. */
/* */
/*************************************************************************/
/* Author: Alan W Black (awb@cs.cmu.edu) */
/* Date: December 1999 */
/*************************************************************************/
/* */
/* Relations */
/* */
/*************************************************************************/
#include "cst_item.h"
#include "cst_relation.h"
#include "cst_utterance.h"
static const char * const cst_relation_noname = "NoName";
cst_relation *new_relation(const char *name, cst_utterance *u)
{
cst_relation *r = cst_utt_alloc(u,cst_relation,1);
r->name = cst_strdup(name);
r->features = new_features_local(u->ctx);
r->head = NULL;
r->utterance = u;
return r;
}
void delete_relation(cst_relation *r)
{
cst_item *p, *np;
if (r != NULL)
{
/* This needs to traverse the *all* items */
for(p=r->head; p; p=np)
{
np = item_next(p);
delete_item(p); /* this *does* go down daughters too */
}
delete_features(r->features);
cst_free(r->name);
cst_utt_free(r->utterance,r);
}
}
cst_item *relation_head(cst_relation *r)
{
return ( r == NULL ? NULL : r->head);
}
cst_item *relation_tail(cst_relation *r)
{
return (r == NULL ? NULL : r->tail);
}
const char *relation_name(cst_relation *r)
{
return (r == NULL ? cst_relation_noname : r->name);
}
cst_item *relation_append(cst_relation *r, cst_item *i)
{
cst_item *ni = new_item_relation(r,i);
if (r->head == NULL)
r->head = ni;
ni->p = r->tail;
if (r->tail)
r->tail->n = ni;
r->tail = ni;
return ni;
}
cst_item *relation_prepend(cst_relation *r, cst_item *i)
{
cst_item *ni = new_item_relation(r,i);
if (r->tail == NULL)
r->tail = ni;
ni->n = r->head;
if (r->head)
r->head->p = ni;
r->head = ni;
return ni;
}