2 * Copyright (C) 1994-1996, Index Data I/S
4 * Sebastian Hammer, Adam Dickmeiss
7 * Revision 1.18 1996-10-29 14:09:44 adam
8 * Use of cisam system - enabled if setting isamc is 1.
10 * Revision 1.17 1996/06/04 10:18:58 adam
11 * Minor changes - removed include of ctype.h.
13 * Revision 1.16 1996/05/13 14:23:05 adam
14 * Work on compaction of set/use bytes in dictionary.
16 * Revision 1.15 1995/11/20 16:59:46 adam
17 * New update method: the 'old' keys are saved for each records.
19 * Revision 1.14 1995/10/30 15:08:08 adam
22 * Revision 1.13 1995/10/27 14:00:11 adam
23 * Implemented detection of database availability.
25 * Revision 1.12 1995/10/17 18:02:08 adam
26 * New feature: databases. Implemented as prefix to words in dictionary.
28 * Revision 1.11 1995/10/06 16:33:37 adam
29 * Use attribute mappings.
31 * Revision 1.10 1995/09/29 14:01:41 adam
34 * Revision 1.9 1995/09/28 12:10:32 adam
35 * Bug fixes. Field prefix used in queries.
37 * Revision 1.8 1995/09/28 09:19:42 adam
38 * xfree/xmalloc used everywhere.
39 * Extract/retrieve method seems to work for text records.
41 * Revision 1.7 1995/09/27 12:22:28 adam
42 * More work on extract in record control.
43 * Field name is not in isam keys but in prefix in dictionary words.
45 * Revision 1.6 1995/09/14 07:48:23 adam
46 * Record control management.
48 * Revision 1.5 1995/09/11 13:09:34 adam
49 * More work on relevance feedback.
51 * Revision 1.4 1995/09/08 14:52:27 adam
52 * Minor changes. Dictionary is lower case now.
54 * Revision 1.3 1995/09/07 13:58:36 adam
55 * New parameter: result-set file descriptor (RSFD) to support multiple
56 * positions within the same result-set.
57 * Boolean operators: and, or, not implemented.
58 * Result-set references.
60 * Revision 1.2 1995/09/06 16:11:17 adam
61 * Option: only one word key per file.
63 * Revision 1.1 1995/09/04 09:10:36 adam
64 * More work on index add/del/update.
65 * Merge sort implemented.
66 * Initial work on z39 server.
77 void key_logdump (int logmask, const void *p)
81 memcpy (&key, p, sizeof(key));
82 logf (logmask, "%7d s=%-4d", key.sysno, key.seqno);
85 int key_compare (const void *p1, const void *p2)
88 memcpy (&i1, p1, sizeof(i1));
89 memcpy (&i2, p2, sizeof(i2));
90 if (i1.sysno != i2.sysno)
92 if (i1.sysno > i2.sysno)
98 if (i1.seqno != i2.seqno)
100 if (i1.seqno > i2.seqno)
106 if (i1.freq != i2.freq)
108 if (i1.freq > i2.freq)
117 int key_qsort_compare (const void *p1, const void *p2)
121 char *cp1 = *(char **) p1;
122 char *cp2 = *(char **) p2;
124 if ((r = strcmp (cp1, cp2)))
127 if ((r = key_compare (cp1+l+1, cp2+l+1)))
129 return cp1[l] - cp2[l];
132 struct iscz_code_info {
136 static void *iscz_code_start (int mode)
138 struct iscz_code_info *p = xmalloc (sizeof(*p));
144 static void iscz_code_stop (int mode, void *p)
149 void iscz_encode_int (unsigned d, char **dst)
151 unsigned char *bp = (unsigned char*) *dst;
160 else if (d <= 4194303)
162 *bp++ = 128 + (d>>16);
163 *bp++ = (d>>8) & 255;
168 *bp++ = 192 + (d>>24);
169 *bp++ = (d>>16) & 255;
170 *bp++ = (d>>8) & 255;
176 int isxz_decode_int (unsigned char **src)
178 unsigned c = *(*src)++;
184 return ((c & 63) << 8) + *(*src)++;
186 c = ((c & 63) << 8) + *(*src)++;
187 c = (c << 8) + *(*src)++;
190 c = ((c & 63) << 8) + *(*src)++;
191 c = (c << 8) + *(*src)++;
192 c = (c << 8) + *(*src)++;
196 static void iscz_code_item (int mode, void *vp, char **dst, char **src)
198 struct iscz_code_info *p = vp;
202 if (mode == ISAMC_ENCODE)
204 memcpy (&tkey, *src, sizeof(struct it_key));
205 d = tkey.sysno - p->key.sysno;
206 iscz_encode_int (d, dst);
209 p->key.sysno = tkey.sysno;
212 iscz_encode_int (tkey.seqno - p->key.seqno, dst);
213 p->key.seqno = tkey.seqno;
214 (*src) += sizeof(struct it_key);
218 d = isxz_decode_int ((unsigned char **) src);
224 d = isxz_decode_int ((unsigned char **) src);
226 memcpy (*dst, &p->key, sizeof(struct it_key));
227 (*dst) += sizeof(struct it_key);
231 ISAMC_M key_isamc_m (void)
233 static ISAMC_M me = NULL;
238 me = isc_getmethod ();
240 me->compare_item = key_compare;
242 me->code_start = iscz_code_start;
243 me->code_item = iscz_code_item;
244 me->code_stop = iscz_code_stop;
246 me->debug = atoi(res_get_def (common_resource, "isamcDebug", "0"));
248 logf (LOG_LOG, "ISAMC system active");