2 * Copyright (C) 1994-2002, Index Data
4 * Sebastian Hammer, Adam Dickmeiss, Heikki Levanto
6 * $Id: rsbetween.c,v 1.1 2002-04-09 15:24:13 heikki Exp $
14 #include <rsbetween.h>
17 static void *r_create(RSET ct, const struct rset_control *sel, void *parms);
18 static RSFD r_open (RSET ct, int flag);
19 static void r_close (RSFD rfd);
20 static void r_delete (RSET ct);
21 static void r_rewind (RSFD rfd);
22 static int r_count (RSET ct);
23 static int r_read (RSFD rfd, void *buf, int *term_index);
24 static int r_write (RSFD rfd, const void *buf);
26 static const struct rset_control control_between =
40 const struct rset_control *rset_kind_between = &control_between;
42 struct rset_between_info {
48 int (*cmp)(const void *p1, const void *p2);
49 struct rset_between_rfd *rfd_list;
52 struct rset_between_rfd {
66 struct rset_between_rfd *next;
67 struct rset_between_info *info;
70 static void *r_create (RSET ct, const struct rset_control *sel, void *parms)
72 rset_between_parms *between_parms = (rset_between_parms *) parms;
73 struct rset_between_info *info;
75 info = (struct rset_between_info *) xmalloc (sizeof(*info));
76 info->key_size = between_parms->key_size;
77 info->rset_l = between_parms->rset_l;
78 info->rset_m = between_parms->rset_m;
79 info->rset_r = between_parms->rset_r;
80 if (rset_is_volatile(info->rset_l) ||
81 rset_is_volatile(info->rset_m) ||
82 rset_is_volatile(info->rset_r))
83 ct->flags |= RSET_FLAG_VOLATILE;
84 info->cmp = between_parms->cmp;
85 info->rfd_list = NULL;
87 info->term_index_s = info->rset_l->no_rset_terms;
89 info->rset_l->no_rset_terms +
90 info->rset_m->no_rset_terms +
91 info->rset_r->no_rset_terms;
92 ct->rset_terms = (RSET_TERM *)
93 xmalloc (sizeof (*ct->rset_terms) * ct->no_rset_terms);
95 memcpy (ct->rset_terms, info->rset_l->rset_terms,
96 info->rset_l->no_rset_terms * sizeof(*ct->rset_terms));
97 memcpy (ct->rset_terms + info->rset_l->no_rset_terms,
98 info->rset_m->rset_terms,
99 info->rset_m->no_rset_terms * sizeof(*ct->rset_terms));
100 memcpy (ct->rset_terms + info->rset_l->no_rset_terms +
101 info->rset_m->no_rset_terms,
102 info->rset_r->rset_terms,
103 info->rset_r->no_rset_terms * sizeof(*ct->rset_terms));
107 static RSFD r_open (RSET ct, int flag)
109 struct rset_between_info *info = (struct rset_between_info *) ct->buf;
110 struct rset_between_rfd *rfd;
112 if (flag & RSETF_WRITE)
114 logf (LOG_FATAL, "between set type is read-only");
117 rfd = (struct rset_between_rfd *) xmalloc (sizeof(*rfd));
118 rfd->next = info->rfd_list;
119 info->rfd_list = rfd;
122 rfd->buf_l = xmalloc (info->key_size);
123 rfd->buf_m = xmalloc (info->key_size);
124 rfd->buf_r = xmalloc (info->key_size);
125 rfd->rfd_l = rset_open (info->rset_l, RSETF_READ);
126 rfd->rfd_m = rset_open (info->rset_m, RSETF_READ);
127 rfd->rfd_r = rset_open (info->rset_r, RSETF_READ);
128 rfd->more_l = rset_read (info->rset_l, rfd->rfd_l, rfd->buf_l,
130 rfd->more_m = rset_read (info->rset_m, rfd->rfd_m, rfd->buf_m,
132 rfd->more_r = rset_read (info->rset_r, rfd->rfd_r, rfd->buf_r,
138 static void r_close (RSFD rfd)
140 struct rset_between_info *info = ((struct rset_between_rfd*)rfd)->info;
141 struct rset_between_rfd **rfdp;
143 for (rfdp = &info->rfd_list; *rfdp; rfdp = &(*rfdp)->next)
146 xfree ((*rfdp)->buf_l);
147 xfree ((*rfdp)->buf_m);
148 xfree ((*rfdp)->buf_r);
149 rset_close (info->rset_l, (*rfdp)->rfd_l);
150 rset_close (info->rset_m, (*rfdp)->rfd_m);
151 rset_close (info->rset_r, (*rfdp)->rfd_r);
152 *rfdp = (*rfdp)->next;
156 logf (LOG_FATAL, "r_close but no rfd match!");
160 static void r_delete (RSET ct)
162 struct rset_between_info *info = (struct rset_between_info *) ct->buf;
164 assert (info->rfd_list == NULL);
165 xfree (ct->rset_terms);
166 rset_delete (info->rset_l);
167 rset_delete (info->rset_m);
168 rset_delete (info->rset_r);
172 static void r_rewind (RSFD rfd)
174 struct rset_between_info *info = ((struct rset_between_rfd*)rfd)->info;
175 struct rset_between_rfd *p = (struct rset_between_rfd *) rfd;
177 logf (LOG_DEBUG, "rsbetween_rewind");
178 rset_rewind (info->rset_l, p->rfd_l);
179 rset_rewind (info->rset_m, p->rfd_m);
180 rset_rewind (info->rset_r, p->rfd_r);
181 p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l, &p->term_index_l);
182 p->more_m = rset_read (info->rset_m, p->rfd_m, p->buf_m, &p->term_index_m);
183 p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r, &p->term_index_r);
187 static int r_count (RSET ct)
192 static int r_read (RSFD rfd, void *buf, int *term_index)
194 struct rset_between_rfd *p = (struct rset_between_rfd *) rfd;
195 struct rset_between_info *info = p->info;
203 /* forward L until past m, count levels, note rec boundaries */
205 cmp_l= (*info->cmp)(p->buf_l, p->buf_m);
207 cmp_l=2; /* past this record */
208 while (cmp_l < 0) /* l before m */
211 p->level=0; /* earlier record */
213 p->level++; /* relevant start tag */
216 p->more_l = rset_read (info->rset_l, p->rfd_l, p->buf_l,
218 cmp_l= (*info->cmp)(p->buf_l, p->buf_m);
224 /* forward R until past m, count levels */
226 cmp_r= (*info->cmp)(p->buf_r, p->buf_m);
229 while (cmp_r < 0) /* r before m */
231 /* -2, earlier record, doesn't matter */
233 p->level--; /* relevant end tag */
236 p->more_r = rset_read (info->rset_r, p->rfd_r, p->buf_r,
238 cmp_r= (*info->cmp)(p->buf_r, p->buf_m);
244 if ( ( p->level <= 0 ) && ! p->more_l)
245 return 0; /* no more start tags, nothing more to find */
247 if ( p->level > 0) /* within a tag pair (or deeper) */
249 memcpy (buf, p->buf_m, info->key_size);
250 *term_index = p->term_index_m;
254 if ( ! p->more_l ) /* not in data, no more starts */
255 return 0; /* ergo, nothing can be found. stop scanning */
257 p->more_m = rset_read (info->rset_m, p->rfd_m, p->buf_m,
261 return 0; /* no more data possible */
266 static int r_write (RSFD rfd, const void *buf)
268 logf (LOG_FATAL, "between set type is read-only");