1 /* $Id: isamb.c,v 1.21 2002-09-03 19:05:02 adam Exp $
2 Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002
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
24 #include <yaz/xmalloc.h>
37 #define ISAMB_DATA_OFFSET 3
39 #define DST_ITEM_MAX 256
41 /* approx 2*4 K + max size of item */
42 #define DST_BUF_SIZE 8448
44 #define ISAMB_CACHE_ENTRY_SIZE 4096
46 struct ISAMB_cache_entry {
51 struct ISAMB_cache_entry *next;
58 struct ISAMB_head head;
59 struct ISAMB_cache_entry *cache_entries;
66 struct ISAMB_file *file;
68 int cache; /* 0=no cache, 1=use cache, -1=dummy isam (for testing only) */
69 int log_io; /* log level for bf_read/bf_write calls */
70 int log_freelist; /* log level for freelist handling */
83 void *decodeClientData;
93 struct ISAMB_block **block;
96 void encode_ptr (char **dst, int pos)
98 memcpy (*dst, &pos, sizeof(pos));
99 (*dst) += sizeof(pos);
102 void decode_ptr (char **src, int *pos)
104 memcpy (pos, *src, sizeof(*pos));
105 (*src) += sizeof(*pos);
108 ISAMB isamb_open (BFiles bfs, const char *name, int writeflag, ISAMC_M method,
111 ISAMB isamb = xmalloc (sizeof(*isamb));
115 isamb->method = (ISAMC_M) xmalloc (sizeof(*method));
116 memcpy (isamb->method, method, sizeof(*method));
119 isamb->cache = cache;
121 isamb->file = xmalloc (sizeof(*isamb->file) * isamb->no_cat);
122 for (i = 0; i<isamb->no_cat; i++)
124 char fname[DST_BUF_SIZE];
125 isamb->file[i].cache_entries = 0;
126 isamb->file[i].head_dirty = 0;
127 sprintf (fname, "%s%c", name, i+'A');
129 isamb->file[i].bf = bf_open (bfs, fname, ISAMB_CACHE_ENTRY_SIZE,
132 isamb->file[i].bf = bf_open (bfs, fname, b_size, writeflag);
135 if (!bf_read (isamb->file[i].bf, 0, 0, sizeof(struct ISAMB_head),
136 &isamb->file[i].head))
138 isamb->file[i].head.first_block = ISAMB_CACHE_ENTRY_SIZE/b_size+1;
139 isamb->file[i].head.last_block = isamb->file[i].head.first_block;
140 isamb->file[i].head.block_size = b_size;
141 isamb->file[i].head.block_max = b_size - ISAMB_DATA_OFFSET;
142 isamb->file[i].head.free_list = 0;
144 assert (isamb->file[i].head.block_size >= ISAMB_DATA_OFFSET);
145 isamb->file[i].head_dirty = 0;
146 assert(isamb->file[i].head.block_size == b_size);
152 static void flush_blocks (ISAMB b, int cat)
154 while (b->file[cat].cache_entries)
156 struct ISAMB_cache_entry *ce_this = b->file[cat].cache_entries;
157 b->file[cat].cache_entries = ce_this->next;
161 yaz_log (b->log_io, "bf_write: flush_blocks");
162 bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
164 xfree (ce_this->buf);
169 static int get_block (ISAMB b, ISAMC_P pos, char *userbuf, int wr)
173 (ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size - 1))
174 * b->file[cat].head.block_size;
175 int norm = pos / (4*ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size);
177 struct ISAMB_cache_entry **ce, *ce_this = 0, **ce_last = 0;
182 assert (ISAMB_CACHE_ENTRY_SIZE >= b->file[cat].head.block_size);
183 for (ce = &b->file[cat].cache_entries; *ce; ce = &(*ce)->next, no++)
186 if ((*ce)->pos == norm)
189 *ce = (*ce)->next; /* remove from list */
191 ce_this->next = b->file[cat].cache_entries; /* move to front */
192 b->file[cat].cache_entries = ce_this;
196 memcpy (ce_this->buf + off, userbuf,
197 b->file[cat].head.block_size);
201 memcpy (userbuf, ce_this->buf + off,
202 b->file[cat].head.block_size);
209 assert (ce_last && *ce_last);
211 *ce_last = 0; /* remove the last entry from list */
214 yaz_log (b->log_io, "bf_write: get_block");
215 bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
217 xfree (ce_this->buf);
220 ce_this = xmalloc (sizeof(*ce_this));
221 ce_this->next = b->file[cat].cache_entries;
222 b->file[cat].cache_entries = ce_this;
223 ce_this->buf = xmalloc (ISAMB_CACHE_ENTRY_SIZE);
225 yaz_log (b->log_io, "bf_read: get_block");
226 if (!bf_read (b->file[cat].bf, norm, 0, 0, ce_this->buf))
227 memset (ce_this->buf, 0, ISAMB_CACHE_ENTRY_SIZE);
230 memcpy (ce_this->buf + off, userbuf, b->file[cat].head.block_size);
236 memcpy (userbuf, ce_this->buf + off, b->file[cat].head.block_size);
242 void isamb_close (ISAMB isamb)
245 for (i = 0; i<isamb->no_cat; i++)
247 flush_blocks (isamb, i);
248 if (isamb->file[i].head_dirty)
249 bf_write (isamb->file[i].bf, 0, 0,
250 sizeof(struct ISAMB_head), &isamb->file[i].head);
254 xfree (isamb->method);
259 struct ISAMB_block *open_block (ISAMB b, ISAMC_P pos)
262 struct ISAMB_block *p;
265 p = xmalloc (sizeof(*p));
268 p->buf = xmalloc (b->file[cat].head.block_size);
270 if (!get_block (b, pos, p->buf, 0))
272 yaz_log (b->log_io, "bf_read: open_block");
273 if (!bf_read (b->file[cat].bf, pos/4, 0, 0, p->buf))
275 yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
276 (long) pos, (long) pos/4);
280 p->bytes = p->buf + ISAMB_DATA_OFFSET;
282 p->size = p->buf[1] + 256 * p->buf[2] - ISAMB_DATA_OFFSET;
286 p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
290 struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
292 struct ISAMB_block *p;
294 p = xmalloc (sizeof(*p));
295 p->buf = xmalloc (b->file[cat].head.block_size);
297 if (!b->file[cat].head.free_list)
300 block_no = b->file[cat].head.last_block++;
301 p->pos = block_no * 4 + cat;
305 p->pos = b->file[cat].head.free_list;
306 if (!get_block (b, p->pos, p->buf, 0))
308 yaz_log (b->log_io, "bf_read: new_block");
309 if (!bf_read (b->file[cat].bf, p->pos/4, 0, 0, p->buf))
311 yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
312 (long) p->pos/4, (long) p->pos/4);
316 yaz_log (b->log_freelist, "got block %d from freelist %d:%d", p->pos,
318 memcpy (&b->file[cat].head.free_list, p->buf, sizeof(int));
321 b->file[cat].head_dirty = 1;
322 memset (p->buf, 0, b->file[cat].head.block_size);
323 p->bytes = p->buf + ISAMB_DATA_OFFSET;
329 p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
333 struct ISAMB_block *new_leaf (ISAMB b, int cat)
335 return new_block (b, 1, cat);
339 struct ISAMB_block *new_int (ISAMB b, int cat)
341 return new_block (b, 0, cat);
344 void close_block (ISAMB b, struct ISAMB_block *p)
350 yaz_log (b->log_freelist, "release block %d from freelist %d:%d",
351 p->pos, p->cat, p->pos/4);
352 memcpy (p->buf, &b->file[p->cat].head.free_list, sizeof(int));
353 b->file[p->cat].head.free_list = p->pos;
354 if (!get_block (b, p->pos, p->buf, 1))
356 yaz_log (b->log_io, "bf_write: close_block");
357 bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
362 int size = p->size + ISAMB_DATA_OFFSET;
364 p->buf[1] = size & 255;
365 p->buf[2] = size >> 8;
366 if (!get_block (b, p->pos, p->buf, 1))
368 yaz_log (b->log_io, "bf_write: close_block");
369 bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
372 (*b->method->code_stop)(ISAMC_DECODE, p->decodeClientData);
377 int insert_sub (ISAMB b, struct ISAMB_block **p,
378 void *new_item, int *mode,
380 struct ISAMB_block **sp,
381 void *sub_item, int *sub_size,
384 int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
386 ISAMC_I stream, struct ISAMB_block **sp,
387 void *split_item, int *split_size, void *last_max_item)
389 char *startp = p->bytes;
391 char *endp = p->bytes + p->size;
393 struct ISAMB_block *sub_p1 = 0, *sub_p2 = 0;
394 char sub_item[DST_ITEM_MAX];
400 decode_ptr (&src, &pos);
405 decode_ptr (&src, &item_len);
406 d = (*b->method->compare_item)(src, lookahead_item);
409 sub_p1 = open_block (b, pos);
411 more = insert_sub (b, &sub_p1, lookahead_item, mode,
413 sub_item, &sub_size, src);
417 decode_ptr (&src, &pos);
421 sub_p1 = open_block (b, pos);
423 more = insert_sub (b, &sub_p1, lookahead_item, mode, stream, &sub_p2,
424 sub_item, &sub_size, last_max_item);
428 /* there was a split - must insert pointer in this one */
429 char dst_buf[DST_BUF_SIZE];
432 assert (sub_size < 30 && sub_size > 1);
434 memcpy (dst, startp, src - startp);
438 encode_ptr (&dst, sub_size); /* sub length and item */
439 memcpy (dst, sub_item, sub_size);
442 encode_ptr (&dst, sub_p2->pos); /* pos */
444 if (endp - src) /* remaining data */
446 memcpy (dst, src, endp - src);
449 p->size = dst - dst_buf;
450 if (p->size <= b->file[p->cat].head.block_max)
452 memcpy (startp, dst_buf, dst - dst_buf);
461 half = src + b->file[p->cat].head.block_size/2;
462 decode_ptr (&src, &pos);
465 decode_ptr (&src, split_size);
467 decode_ptr (&src, &pos);
469 p_new_size = src - dst_buf;
470 memcpy (p->bytes, dst_buf, p_new_size);
472 decode_ptr (&src, split_size);
473 memcpy (split_item, src, *split_size);
476 *sp = new_int (b, p->cat);
477 (*sp)->size = endp - src;
478 memcpy ((*sp)->bytes, src, (*sp)->size);
480 p->size = p_new_size;
483 close_block (b, sub_p2);
485 close_block (b, sub_p1);
490 int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
491 int *lookahead_mode, ISAMC_I stream, struct ISAMB_block **sp2,
492 void *sub_item, int *sub_size,
495 struct ISAMB_block *p = *sp1;
496 char *src = 0, *endp = 0;
497 char dst_buf[DST_BUF_SIZE], *dst = dst_buf;
499 void *c1 = (*b->method->code_start)(ISAMC_DECODE);
500 void *c2 = (*b->method->code_start)(ISAMC_ENCODE);
502 int quater = b->file[b->no_cat-1].head.block_max / 4;
503 char *cut = dst_buf + quater * 2;
504 char *maxp = dst_buf + b->file[b->no_cat-1].head.block_max;
507 char cut_item_buf[DST_ITEM_MAX];
508 int cut_item_size = 0;
512 char file_item_buf[DST_ITEM_MAX];
513 char *file_item = file_item_buf;
516 endp = p->bytes + p->size;
517 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
522 char *lookahead_next;
526 d = (*b->method->compare_item)(file_item_buf, lookahead_item);
530 dst_item = lookahead_item;
531 assert (*lookahead_mode);
534 dst_item = file_item_buf;
535 if (!*lookahead_mode && d == 0)
539 else if (!half1 && dst > cut)
541 char *dst_item_0 = dst_item;
542 half1 = dst; /* candidate for splitting */
544 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
546 cut_item_size = dst_item - dst_item_0;
547 memcpy (cut_item_buf, dst_item_0, cut_item_size);
552 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
562 lookahead_next = lookahead_item;
563 if (!(*stream->read_item)(stream->clientData,
570 if (lookahead_item && max_item &&
571 (*b->method->compare_item)(max_item, lookahead_item) <= 0)
582 lookahead_next = lookahead_item;
583 if (!(*stream->read_item)(stream->clientData,
584 &lookahead_next, lookahead_mode))
591 file_item = file_item_buf;
592 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
598 file_item = file_item_buf;
599 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
603 maxp = dst_buf + b->file[b->no_cat-1].head.block_max + quater;
604 while (lookahead_item)
606 char *dst_item = lookahead_item;
610 (*b->method->compare_item)(max_item, lookahead_item) <= 0)
615 if (!*lookahead_mode)
617 yaz_log (LOG_WARN, "Inconsistent register (2)");
620 else if (!half1 && dst > cut)
622 char *dst_item_0 = dst_item;
623 half1 = dst; /* candidate for splitting */
625 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
627 cut_item_size = dst_item - dst_item_0;
628 memcpy (cut_item_buf, dst_item_0, cut_item_size);
633 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
642 dst_item = lookahead_item;
643 if (!(*stream->read_item)(stream->clientData, &dst_item,
650 new_size = dst - dst_buf;
651 if (p && p->cat != b->no_cat-1 &&
652 new_size > b->file[p->cat].head.block_max)
654 /* non-btree block will be removed */
657 /* delete it too!! */
658 p = 0; /* make a new one anyway */
661 { /* must create a new one */
663 for (i = 0; i < b->no_cat; i++)
664 if (new_size <= b->file[i].head.block_max)
670 if (new_size > b->file[p->cat].head.block_max)
673 char *cut_item = cut_item_buf;
679 p->size = half1 - dst_buf;
680 memcpy (p->bytes, dst_buf, half1 - dst_buf);
683 *sp2 = new_leaf (b, p->cat);
685 (*b->method->code_reset)(c2);
687 first_dst = (*sp2)->bytes;
689 (*b->method->code_item)(ISAMC_ENCODE, c2, &first_dst, &cut_item);
691 memcpy (first_dst, half2, dst - half2);
693 (*sp2)->size = (first_dst - (*sp2)->bytes) + (dst - half2);
696 memcpy (sub_item, cut_item_buf, cut_item_size);
697 *sub_size = cut_item_size;
701 memcpy (p->bytes, dst_buf, dst - dst_buf);
704 (*b->method->code_stop)(ISAMC_DECODE, c1);
705 (*b->method->code_stop)(ISAMC_ENCODE, c2);
710 int insert_sub (ISAMB b, struct ISAMB_block **p, void *new_item,
713 struct ISAMB_block **sp,
714 void *sub_item, int *sub_size,
717 if (!*p || (*p)->leaf)
718 return insert_leaf (b, p, new_item, mode, stream, sp, sub_item,
721 return insert_int (b, *p, new_item, mode, stream, sp, sub_item,
725 int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
727 char item_buf[DST_ITEM_MAX];
739 (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
744 more = (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
747 struct ISAMB_block *p = 0, *sp = 0;
748 char sub_item[DST_ITEM_MAX];
752 p = open_block (b, pos);
753 more = insert_sub (b, &p, item_buf, &i_mode, stream, &sp,
754 sub_item, &sub_size, 0);
756 { /* increase level of tree by one */
757 struct ISAMB_block *p2 = new_int (b, p->cat);
758 char *dst = p2->bytes + p2->size;
760 encode_ptr (&dst, p->pos);
761 assert (sub_size < 20);
762 encode_ptr (&dst, sub_size);
763 memcpy (dst, sub_item, sub_size);
765 encode_ptr (&dst, sp->pos);
767 p2->size = dst - p2->bytes;
768 pos = p2->pos; /* return new super page */
773 pos = p->pos; /* return current one (again) */
779 ISAMB_PP isamb_pp_open_x (ISAMB isamb, ISAMB_P pos, int *level)
781 ISAMB_PP pp = xmalloc (sizeof(*pp));
784 pp->block = xmalloc (10 * sizeof(*pp->block));
792 struct ISAMB_block *p = open_block (isamb, pos);
793 char *src = p->bytes + p->offset;
794 pp->block[pp->level] = p;
796 pp->total_size += p->size;
802 decode_ptr (&src, &pos);
803 p->offset = src - p->bytes;
806 pp->block[pp->level+1] = 0;
812 ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
814 return isamb_pp_open_x (isamb, pos, 0);
817 void isamb_pp_close_x (ISAMB_PP pp, int *size, int *blocks)
823 *size = pp->total_size;
825 *blocks = pp->no_blocks;
826 for (i = 0; i <= pp->level; i++)
827 close_block (pp->isamb, pp->block[i]);
832 int isamb_block_info (ISAMB isamb, int cat)
834 if (cat >= 0 && cat < isamb->no_cat)
835 return isamb->file[cat].head.block_size;
839 void isamb_pp_close (ISAMB_PP pp)
841 isamb_pp_close_x (pp, 0, 0);
844 int isamb_pp_read (ISAMB_PP pp, void *buf)
848 struct ISAMB_block *p = pp->block[pp->level];
852 while (p->offset == p->size)
855 while (p->offset == p->size)
859 close_block (pp->isamb, pp->block[pp->level]);
860 pp->block[pp->level] = 0;
862 p = pp->block[pp->level];
863 assert (!p->leaf); /* must be int */
865 src = p->bytes + p->offset;
867 decode_ptr (&src, &item_len);
869 decode_ptr (&src, &pos);
871 p->offset = src - (char*) p->bytes;
877 pp->block[pp->level] = p = open_block (pp->isamb, pos);
879 pp->total_size += p->size;
882 if (p->leaf) /* leaf */
886 src = p->bytes + p->offset;
887 decode_ptr (&src, &pos);
888 p->offset = src - (char*) p->bytes;
892 assert (p->offset < p->size);
894 src = p->bytes + p->offset;
895 (*pp->isamb->method->code_item)(ISAMC_DECODE, p->decodeClientData,
897 p->offset = src - (char*) p->bytes;
901 int isamb_pp_num (ISAMB_PP pp)