2 * Copyright (C) 1994-1999, Index Data
4 * Sebastian Hammer, Adam Dickmeiss
7 * Revision 1.12 1999-05-26 07:49:14 adam
10 * Revision 1.11 1999/02/02 14:51:36 adam
11 * Updated WIN32 code specific sections. Changed header.
13 * Revision 1.10 1998/03/05 08:36:28 adam
14 * New result set model.
16 * Revision 1.9 1997/12/18 10:54:25 adam
17 * New method result set method rs_hits that returns the number of
18 * hits in result-set (if known). The ranked result set returns real
19 * number of hits but only when not combined with other operands.
21 * Revision 1.8 1996/10/29 13:55:24 adam
22 * Include of zebrautl.h instead of alexutil.h.
24 * Revision 1.7 1995/12/11 09:15:25 adam
25 * New set types: sand/sor/snot - ranked versions of and/or/not in
26 * ranked/semi-ranked result sets.
27 * Note: the snot not finished yet.
28 * New rset member: flag.
29 * Bug fix: r_delete in rsrel.c did free bad memory block.
31 * Revision 1.6 1995/10/12 12:41:57 adam
32 * Private info (buf) moved from struct rset_control to struct rset.
33 * Bug fixes in relevance.
35 * Revision 1.5 1995/10/10 14:00:04 adam
36 * Function rset_open changed its wflag parameter to general flags.
38 * Revision 1.4 1995/10/06 14:38:06 adam
39 * New result set method: r_score.
40 * Local no (sysno) and score is transferred to retrieveCtrl.
42 * Revision 1.3 1995/09/08 14:52:42 adam
43 * Work on relevance feedback.
45 * Revision 1.2 1995/09/07 13:58:43 adam
46 * New parameter: result-set file descriptor (RSFD) to support multiple
47 * positions within the same result-set.
48 * Boolean operators: and, or, not implemented.
50 * Revision 1.1 1995/09/06 10:35:44 adam
51 * Null set implemented.
59 static void *r_create(RSET ct, const struct rset_control *sel, void *parms);
60 static RSFD r_open (RSET ct, int flag);
61 static void r_close (RSFD rfd);
62 static void r_delete (RSET ct);
63 static void r_rewind (RSFD rfd);
64 static int r_count (RSET ct);
65 static int r_read (RSFD rfd, void *buf, int *term_index);
66 static int r_write (RSFD rfd, const void *buf);
68 static const struct rset_control control =
81 const struct rset_control *rset_kind_null = &control;
83 static void *r_create(RSET ct, const struct rset_control *sel, void *parms)
85 rset_null_parms *null_parms = (rset_null_parms *) parms;
87 ct->no_rset_terms = 1;
88 ct->rset_terms = (RSET_TERM *) xmalloc (sizeof(*ct->rset_terms));
90 ct->rset_terms[0] = null_parms->rset_term;
92 ct->rset_terms[0] = rset_term_create ("term", -1, "rank-0");
93 ct->rset_terms[0]->nn = 0;
98 static RSFD r_open (RSET ct, int flag)
100 if (flag & RSETF_WRITE)
102 logf (LOG_FATAL, "NULL set type is read-only");
108 static void r_close (RSFD rfd)
112 static void r_delete (RSET ct)
114 rset_term_destroy (ct->rset_terms[0]);
115 xfree (ct->rset_terms);
118 static void r_rewind (RSFD rfd)
120 logf (LOG_DEBUG, "rsnull_rewind");
123 static int r_count (RSET ct)
128 static int r_read (RSFD rfd, void *buf, int *term_index)
134 static int r_write (RSFD rfd, const void *buf)
136 logf (LOG_FATAL, "NULL set type is read-only");