1 /* $Id: isams.c,v 1.8 2004-11-19 10:27:11 heikki Exp $
2 Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003,2004
5 This file is part of the Zebra server.
7 Zebra is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with Zebra; see the file LICENSE.zebra. If not, write to the
19 Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
37 typedef unsigned ISAMS_BLOCK_SIZE;
55 void *decodeClientData;
60 void isams_getmethod (ISAMS_M *m)
62 m->codec.start = NULL;
63 m->codec.decode = NULL;
64 m->codec.encode = NULL;
66 m->codec.reset = NULL;
68 m->compare_item = NULL;
75 ISAMS isams_open (BFiles bfs, const char *name, int writeflag,
78 ISAMS is = (ISAMS) xmalloc (sizeof(*is));
80 is->method = (ISAMS_M *) xmalloc (sizeof(*is->method));
81 memcpy (is->method, method, sizeof(*method));
82 is->block_size = is->method->block_size;
83 is->debug = is->method->debug;
85 is->bf = bf_open (bfs, name, is->block_size, writeflag);
87 if (!bf_read (is->bf, 0, 0, sizeof(ISAMS_head), &is->head))
89 is->head.last_block = 1;
90 is->head.last_offset = 0;
92 memcpy (&is->head_old, &is->head, sizeof(is->head));
93 is->merge_buf = (char *) xmalloc(2*is->block_size);
94 memset(is->merge_buf, 0, 2*is->block_size);
98 int isams_close (ISAMS is)
100 if (memcmp(&is->head, &is->head_old, sizeof(is->head)))
102 if (is->head.last_offset)
103 bf_write(is->bf, is->head.last_block, 0, is->head.last_offset,
105 bf_write (is->bf, 0, 0, sizeof(is->head), &is->head);
108 xfree (is->merge_buf);
114 ISAMS_P isams_merge (ISAMS is, ISAMS_I data)
119 int first_block = is->head.last_block;
120 int first_offset = is->head.last_offset;
123 r_clientData = (*is->method->codec.start)();
125 is->head.last_offset += sizeof(int);
126 if (is->head.last_offset > is->block_size)
129 yaz_log (YLOG_LOG, "first_block=%d", first_block);
130 bf_write(is->bf, is->head.last_block, 0, 0, is->merge_buf);
131 (is->head.last_block)++;
132 is->head.last_offset -= is->block_size;
133 memcpy (is->merge_buf, is->merge_buf + is->block_size,
134 is->head.last_offset);
138 char *tmp_ptr = i_item;
139 i_more = (*data->read_item)(data->clientData, &tmp_ptr, &i_mode);
146 char *r_out_ptr = is->merge_buf + is->head.last_offset;
148 const char *i_item_ptr = i_item;
149 (*is->method->codec.encode)(r_clientData, &r_out_ptr, &i_item_ptr);
150 is->head.last_offset = r_out_ptr - is->merge_buf;
151 if (is->head.last_offset > is->block_size)
153 bf_write(is->bf, is->head.last_block, 0, 0, is->merge_buf);
154 (is->head.last_block)++;
155 is->head.last_offset -= is->block_size;
156 memcpy (is->merge_buf, is->merge_buf + is->block_size,
157 is->head.last_offset);
162 (*is->method->codec.stop)(r_clientData);
163 if (first_block == is->head.last_block)
164 memcpy(is->merge_buf + first_offset, &count, sizeof(int));
165 else if (first_block == is->head.last_block-1)
167 int gap = first_offset + sizeof(int) - is->block_size;
168 assert (gap <= (int) sizeof(int));
171 if (gap < (int) sizeof(int))
172 bf_write(is->bf, first_block, first_offset, sizeof(int)-gap,
174 memcpy (is->merge_buf, ((char*)&count)+(sizeof(int)-gap), gap);
177 bf_write(is->bf, first_block, first_offset, sizeof(int), &count);
181 bf_write(is->bf, first_block, first_offset, sizeof(int), &count);
183 return first_block * is->block_size + first_offset;
186 ISAMS_PP isams_pp_open (ISAMS is, ISAMS_P pos)
188 ISAMS_PP pp = (ISAMS_PP) xmalloc (sizeof(*pp));
191 yaz_log (YLOG_LOG, "isams: isams_pp_open pos=%ld", (long) pos);
193 pp->decodeClientData = (*is->method->codec.start)();
196 pp->buf = (char *) xmalloc(is->block_size*2);
197 pp->block_no = (int) (pos/is->block_size);
198 pp->block_offset = (int) (pos - pp->block_no * is->block_size);
200 yaz_log (YLOG_LOG, "isams: isams_pp_open off=%d no=%d",
201 pp->block_offset, pp->block_no);
204 bf_read (is->bf, pp->block_no, 0, 0, pp->buf);
205 bf_read (is->bf, pp->block_no+1, 0, 0, pp->buf + is->block_size);
206 memcpy(&pp->numKeys, pp->buf + pp->block_offset, sizeof(int));
208 yaz_log (YLOG_LOG, "isams: isams_pp_open numKeys=%d", pp->numKeys);
209 pp->block_offset += sizeof(int);
214 void isams_pp_close (ISAMS_PP pp)
216 (*pp->is->method->codec.stop)(pp->decodeClientData);
221 int isams_pp_num (ISAMS_PP pp)
226 int isams_pp_read (ISAMS_PP pp, void *buf)
229 return isams_read_item (pp, &cp);
232 int isams_read_item (ISAMS_PP pp, char **dst)
235 if (pp->numRead >= pp->numKeys)
238 if (pp->block_offset > pp->is->block_size)
240 pp->block_offset -= pp->is->block_size;
242 memcpy (pp->buf, pp->buf + pp->is->block_size, pp->is->block_size);
243 bf_read (pp->is->bf, pp->block_no+1, 0, 0,
244 pp->buf + pp->is->block_size);
246 src = pp->buf + pp->block_offset;
247 (*pp->is->method->codec.decode)(pp->decodeClientData, dst, &src);
248 pp->block_offset = src - pp->buf;