2 * Copyright (C) 1994-1998, Index Data I/S
4 * Sebastian Hammer, Adam Dickmeiss
7 * Revision 1.23 1998-03-05 08:45:12 adam
8 * New result set model and modular ranking system. Moved towards
9 * descent server API. System information stored as "SGML" records.
11 * Revision 1.22 1997/09/22 12:39:06 adam
12 * Added get_pos method for the ranked result sets.
14 * Revision 1.21 1997/09/17 12:19:13 adam
15 * Zebra version corresponds to YAZ version 1.4.
16 * Changed Zebra server so that it doesn't depend on global common_resource.
18 * Revision 1.20 1996/12/23 15:30:44 adam
20 * Bug fix: result sets weren't deleted after server shut down.
22 * Revision 1.19 1996/12/11 12:08:00 adam
23 * Added better compression.
25 * Revision 1.18 1996/10/29 14:09:44 adam
26 * Use of cisam system - enabled if setting isamc is 1.
28 * Revision 1.17 1996/06/04 10:18:58 adam
29 * Minor changes - removed include of ctype.h.
31 * Revision 1.16 1996/05/13 14:23:05 adam
32 * Work on compaction of set/use bytes in dictionary.
34 * Revision 1.15 1995/11/20 16:59:46 adam
35 * New update method: the 'old' keys are saved for each records.
37 * Revision 1.14 1995/10/30 15:08:08 adam
40 * Revision 1.13 1995/10/27 14:00:11 adam
41 * Implemented detection of database availability.
43 * Revision 1.12 1995/10/17 18:02:08 adam
44 * New feature: databases. Implemented as prefix to words in dictionary.
46 * Revision 1.11 1995/10/06 16:33:37 adam
47 * Use attribute mappings.
49 * Revision 1.10 1995/09/29 14:01:41 adam
52 * Revision 1.9 1995/09/28 12:10:32 adam
53 * Bug fixes. Field prefix used in queries.
55 * Revision 1.8 1995/09/28 09:19:42 adam
56 * xfree/xmalloc used everywhere.
57 * Extract/retrieve method seems to work for text records.
59 * Revision 1.7 1995/09/27 12:22:28 adam
60 * More work on extract in record control.
61 * Field name is not in isam keys but in prefix in dictionary words.
63 * Revision 1.6 1995/09/14 07:48:23 adam
64 * Record control management.
66 * Revision 1.5 1995/09/11 13:09:34 adam
67 * More work on relevance feedback.
69 * Revision 1.4 1995/09/08 14:52:27 adam
70 * Minor changes. Dictionary is lower case now.
72 * Revision 1.3 1995/09/07 13:58:36 adam
73 * New parameter: result-set file descriptor (RSFD) to support multiple
74 * positions within the same result-set.
75 * Boolean operators: and, or, not implemented.
76 * Result-set references.
78 * Revision 1.2 1995/09/06 16:11:17 adam
79 * Option: only one word key per file.
81 * Revision 1.1 1995/09/04 09:10:36 adam
82 * More work on index add/del/update.
83 * Merge sort implemented.
84 * Initial work on z39 server.
95 void key_logdump (int logmask, const void *p)
99 memcpy (&key, p, sizeof(key));
100 logf (logmask, "%7d s=%-4d", key.sysno, key.seqno);
103 int key_compare_it (const void *p1, const void *p2)
105 if (((struct it_key *) p1)->sysno != ((struct it_key *) p2)->sysno)
107 if (((struct it_key *) p1)->sysno > ((struct it_key *) p2)->sysno)
112 if (((struct it_key *) p1)->seqno != ((struct it_key *) p2)->seqno)
114 if (((struct it_key *) p1)->seqno > ((struct it_key *) p2)->seqno)
122 int key_compare (const void *p1, const void *p2)
124 struct it_key i1, i2;
125 memcpy (&i1, p1, sizeof(i1));
126 memcpy (&i2, p2, sizeof(i2));
127 if (i1.sysno != i2.sysno)
129 if (i1.sysno > i2.sysno)
134 if (i1.seqno != i2.seqno)
136 if (i1.seqno > i2.seqno)
144 int key_qsort_compare (const void *p1, const void *p2)
148 char *cp1 = *(char **) p1;
149 char *cp2 = *(char **) p2;
151 if ((r = strcmp (cp1, cp2)))
154 if ((r = key_compare (cp1+l+1, cp2+l+1)))
156 return cp1[l] - cp2[l];
159 int key_get_pos (const void *p)
162 memcpy (&key, p, sizeof(key));
166 struct iscz1_code_info {
170 static void *iscz1_code_start (int mode)
172 struct iscz1_code_info *p = xmalloc (sizeof(*p));
178 static void iscz1_code_stop (int mode, void *p)
183 void iscz1_encode_int (unsigned d, char **dst)
185 unsigned char *bp = (unsigned char*) *dst;
194 else if (d <= 4194303)
196 *bp++ = 128 + (d>>16);
197 *bp++ = (d>>8) & 255;
202 *bp++ = 192 + (d>>24);
203 *bp++ = (d>>16) & 255;
204 *bp++ = (d>>8) & 255;
210 int iscz1_decode_int (unsigned char **src)
212 unsigned c = *(*src)++;
218 return ((c & 63) << 8) + *(*src)++;
220 c = ((c & 63) << 8) + *(*src)++;
221 c = (c << 8) + *(*src)++;
224 c = ((c & 63) << 8) + *(*src)++;
225 c = (c << 8) + *(*src)++;
226 c = (c << 8) + *(*src)++;
230 static void iscz1_code_item (int mode, void *vp, char **dst, char **src)
232 struct iscz1_code_info *p = vp;
236 if (mode == ISAMC_ENCODE)
238 memcpy (&tkey, *src, sizeof(struct it_key));
239 d = tkey.sysno - p->key.sysno;
242 iscz1_encode_int (2*tkey.seqno + 1, dst);
243 iscz1_encode_int (d, dst);
245 p->key.seqno = tkey.seqno;
249 iscz1_encode_int (2*(tkey.seqno - p->key.seqno), dst);
250 p->key.seqno = tkey.seqno;
252 (*src) += sizeof(struct it_key);
256 d = iscz1_decode_int ((unsigned char **) src);
260 p->key.sysno += iscz1_decode_int ((unsigned char **) src);
263 p->key.seqno += d>>1;
264 memcpy (*dst, &p->key, sizeof(struct it_key));
265 (*dst) += sizeof(struct it_key);
269 ISAMC_M key_isamc_m (Res res)
271 static ISAMC_M me = NULL;
276 me = isc_getmethod ();
278 me->compare_item = key_compare;
280 me->code_start = iscz1_code_start;
281 me->code_item = iscz1_code_item;
282 me->code_stop = iscz1_code_stop;
284 me->debug = atoi(res_get_def (res, "isamcDebug", "0"));