1 /* $Id: isamb.c,v 1.24 2003-03-17 20:22:54 adam Exp $
2 Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003
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;
122 isamb->file = xmalloc (sizeof(*isamb->file) * isamb->no_cat);
123 for (i = 0; i<isamb->no_cat; i++)
125 char fname[DST_BUF_SIZE];
126 isamb->file[i].cache_entries = 0;
127 isamb->file[i].head_dirty = 0;
128 sprintf (fname, "%s%c", name, i+'A');
130 isamb->file[i].bf = bf_open (bfs, fname, ISAMB_CACHE_ENTRY_SIZE,
133 isamb->file[i].bf = bf_open (bfs, fname, b_size, writeflag);
136 if (!bf_read (isamb->file[i].bf, 0, 0, sizeof(struct ISAMB_head),
137 &isamb->file[i].head))
139 isamb->file[i].head.first_block = ISAMB_CACHE_ENTRY_SIZE/b_size+1;
140 isamb->file[i].head.last_block = isamb->file[i].head.first_block;
141 isamb->file[i].head.block_size = b_size;
142 isamb->file[i].head.block_max = b_size - ISAMB_DATA_OFFSET;
143 isamb->file[i].head.free_list = 0;
145 assert (isamb->file[i].head.block_size >= ISAMB_DATA_OFFSET);
146 isamb->file[i].head_dirty = 0;
147 assert(isamb->file[i].head.block_size == b_size);
153 static void flush_blocks (ISAMB b, int cat)
155 while (b->file[cat].cache_entries)
157 struct ISAMB_cache_entry *ce_this = b->file[cat].cache_entries;
158 b->file[cat].cache_entries = ce_this->next;
162 yaz_log (b->log_io, "bf_write: flush_blocks");
163 bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
165 xfree (ce_this->buf);
170 static int get_block (ISAMB b, ISAMC_P pos, char *userbuf, int wr)
174 (ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size - 1))
175 * b->file[cat].head.block_size;
176 int norm = pos / (4*ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size);
178 struct ISAMB_cache_entry **ce, *ce_this = 0, **ce_last = 0;
183 assert (ISAMB_CACHE_ENTRY_SIZE >= b->file[cat].head.block_size);
184 for (ce = &b->file[cat].cache_entries; *ce; ce = &(*ce)->next, no++)
187 if ((*ce)->pos == norm)
190 *ce = (*ce)->next; /* remove from list */
192 ce_this->next = b->file[cat].cache_entries; /* move to front */
193 b->file[cat].cache_entries = ce_this;
197 memcpy (ce_this->buf + off, userbuf,
198 b->file[cat].head.block_size);
202 memcpy (userbuf, ce_this->buf + off,
203 b->file[cat].head.block_size);
210 assert (ce_last && *ce_last);
212 *ce_last = 0; /* remove the last entry from list */
215 yaz_log (b->log_io, "bf_write: get_block");
216 bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
218 xfree (ce_this->buf);
221 ce_this = xmalloc (sizeof(*ce_this));
222 ce_this->next = b->file[cat].cache_entries;
223 b->file[cat].cache_entries = ce_this;
224 ce_this->buf = xmalloc (ISAMB_CACHE_ENTRY_SIZE);
226 yaz_log (b->log_io, "bf_read: get_block");
227 if (!bf_read (b->file[cat].bf, norm, 0, 0, ce_this->buf))
228 memset (ce_this->buf, 0, ISAMB_CACHE_ENTRY_SIZE);
231 memcpy (ce_this->buf + off, userbuf, b->file[cat].head.block_size);
237 memcpy (userbuf, ce_this->buf + off, b->file[cat].head.block_size);
243 void isamb_close (ISAMB isamb)
246 for (i = 0; i<isamb->no_cat; i++)
248 flush_blocks (isamb, i);
249 if (isamb->file[i].head_dirty)
250 bf_write (isamb->file[i].bf, 0, 0,
251 sizeof(struct ISAMB_head), &isamb->file[i].head);
253 bf_close (isamb->file[i].bf);
256 xfree (isamb->method);
261 struct ISAMB_block *open_block (ISAMB b, ISAMC_P pos)
264 struct ISAMB_block *p;
267 p = xmalloc (sizeof(*p));
270 p->buf = xmalloc (b->file[cat].head.block_size);
272 if (!get_block (b, pos, p->buf, 0))
274 yaz_log (b->log_io, "bf_read: open_block");
275 if (!bf_read (b->file[cat].bf, pos/4, 0, 0, p->buf))
277 yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
278 (long) pos, (long) pos/4);
282 p->bytes = p->buf + ISAMB_DATA_OFFSET;
284 p->size = (p->buf[1] + 256 * p->buf[2]) - ISAMB_DATA_OFFSET;
287 fprintf (stderr, "pos=%d\n", pos);
289 assert (p->size >= 0);
293 p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
297 struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
299 struct ISAMB_block *p;
301 p = xmalloc (sizeof(*p));
302 p->buf = xmalloc (b->file[cat].head.block_size);
304 if (!b->file[cat].head.free_list)
307 block_no = b->file[cat].head.last_block++;
308 p->pos = block_no * 4 + cat;
312 p->pos = b->file[cat].head.free_list;
313 assert((p->pos & 3) == cat);
314 if (!get_block (b, p->pos, p->buf, 0))
316 yaz_log (b->log_io, "bf_read: new_block");
317 if (!bf_read (b->file[cat].bf, p->pos/4, 0, 0, p->buf))
319 yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
320 (long) p->pos/4, (long) p->pos/4);
324 yaz_log (b->log_freelist, "got block %d from freelist %d:%d", p->pos,
326 memcpy (&b->file[cat].head.free_list, p->buf, sizeof(int));
329 b->file[cat].head_dirty = 1;
330 memset (p->buf, 0, b->file[cat].head.block_size);
331 p->bytes = p->buf + ISAMB_DATA_OFFSET;
337 p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
341 struct ISAMB_block *new_leaf (ISAMB b, int cat)
343 return new_block (b, 1, cat);
347 struct ISAMB_block *new_int (ISAMB b, int cat)
349 return new_block (b, 0, cat);
352 static void check_block (ISAMB b, struct ISAMB_block *p)
361 char *startp = p->bytes;
363 char *endp = p->bytes + p->size;
366 decode_ptr (&src, &pos);
367 assert ((pos&3) == p->cat);
371 decode_ptr (&src, &item_len);
372 assert (item_len > 0 && item_len < 30);
374 decode_ptr (&src, &pos);
375 assert ((pos&3) == p->cat);
380 void close_block (ISAMB b, struct ISAMB_block *p)
386 yaz_log (b->log_freelist, "release block %d from freelist %d:%d",
387 p->pos, p->cat, p->pos/4);
388 memcpy (p->buf, &b->file[p->cat].head.free_list, sizeof(int));
389 b->file[p->cat].head.free_list = p->pos;
390 if (!get_block (b, p->pos, p->buf, 1))
392 yaz_log (b->log_io, "bf_write: close_block (deleted)");
393 bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
398 int size = p->size + ISAMB_DATA_OFFSET;
399 assert (p->size >= 0);
401 p->buf[1] = size & 255;
402 p->buf[2] = size >> 8;
404 if (!get_block (b, p->pos, p->buf, 1))
406 yaz_log (b->log_io, "bf_write: close_block");
407 bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
410 (*b->method->code_stop)(ISAMC_DECODE, p->decodeClientData);
415 int insert_sub (ISAMB b, struct ISAMB_block **p,
416 void *new_item, int *mode,
418 struct ISAMB_block **sp,
419 void *sub_item, int *sub_size,
422 int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
424 ISAMC_I stream, struct ISAMB_block **sp,
425 void *split_item, int *split_size, void *last_max_item)
427 char *startp = p->bytes;
429 char *endp = p->bytes + p->size;
431 struct ISAMB_block *sub_p1 = 0, *sub_p2 = 0;
432 char sub_item[DST_ITEM_MAX];
438 assert(p->size >= 0);
439 decode_ptr (&src, &pos);
445 decode_ptr (&src, &item_len);
446 d = (*b->method->compare_item)(src, lookahead_item);
449 sub_p1 = open_block (b, pos);
451 more = insert_sub (b, &sub_p1, lookahead_item, mode,
453 sub_item, &sub_size, src);
458 decode_ptr (&src, &pos);
462 sub_p1 = open_block (b, pos);
464 more = insert_sub (b, &sub_p1, lookahead_item, mode, stream, &sub_p2,
465 sub_item, &sub_size, last_max_item);
469 /* there was a split - must insert pointer in this one */
470 char dst_buf[DST_BUF_SIZE];
473 assert (sub_size < 30 && sub_size > 1);
475 memcpy (dst, startp, src - startp);
479 encode_ptr (&dst, sub_size); /* sub length and item */
480 memcpy (dst, sub_item, sub_size);
483 encode_ptr (&dst, sub_p2->pos); /* pos */
485 if (endp - src) /* remaining data */
487 memcpy (dst, src, endp - src);
490 p->size = dst - dst_buf;
491 assert (p->size >= 0);
492 if (p->size <= b->file[p->cat].head.block_max)
494 memcpy (startp, dst_buf, dst - dst_buf);
503 half = src + b->file[p->cat].head.block_size/2;
504 decode_ptr (&src, &pos);
507 decode_ptr (&src, split_size);
509 decode_ptr (&src, &pos);
511 p_new_size = src - dst_buf;
512 memcpy (p->bytes, dst_buf, p_new_size);
514 decode_ptr (&src, split_size);
515 memcpy (split_item, src, *split_size);
518 *sp = new_int (b, p->cat);
519 (*sp)->size = endp - src;
520 memcpy ((*sp)->bytes, src, (*sp)->size);
522 p->size = p_new_size;
525 close_block (b, sub_p2);
527 close_block (b, sub_p1);
532 int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
533 int *lookahead_mode, ISAMC_I stream, struct ISAMB_block **sp2,
534 void *sub_item, int *sub_size,
537 struct ISAMB_block *p = *sp1;
538 char *src = 0, *endp = 0;
539 char dst_buf[DST_BUF_SIZE], *dst = dst_buf;
541 void *c1 = (*b->method->code_start)(ISAMC_DECODE);
542 void *c2 = (*b->method->code_start)(ISAMC_ENCODE);
544 int quater = b->file[b->no_cat-1].head.block_max / 4;
545 char *cut = dst_buf + quater * 2;
546 char *maxp = dst_buf + b->file[b->no_cat-1].head.block_max;
549 char cut_item_buf[DST_ITEM_MAX];
550 int cut_item_size = 0;
554 char file_item_buf[DST_ITEM_MAX];
555 char *file_item = file_item_buf;
558 endp = p->bytes + p->size;
559 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
564 char *lookahead_next;
568 d = (*b->method->compare_item)(file_item_buf, lookahead_item);
572 dst_item = lookahead_item;
573 assert (*lookahead_mode);
576 dst_item = file_item_buf;
577 if (!*lookahead_mode && d == 0)
581 else if (!half1 && dst > cut)
583 char *dst_item_0 = dst_item;
584 half1 = dst; /* candidate for splitting */
586 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
588 cut_item_size = dst_item - dst_item_0;
589 memcpy (cut_item_buf, dst_item_0, cut_item_size);
594 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
604 lookahead_next = lookahead_item;
605 if (!(*stream->read_item)(stream->clientData,
612 if (lookahead_item && max_item &&
613 (*b->method->compare_item)(max_item, lookahead_item) <= 0)
624 lookahead_next = lookahead_item;
625 if (!(*stream->read_item)(stream->clientData,
626 &lookahead_next, lookahead_mode))
633 file_item = file_item_buf;
634 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
640 file_item = file_item_buf;
641 (*b->method->code_item)(ISAMC_DECODE, c1, &file_item, &src);
645 maxp = dst_buf + b->file[b->no_cat-1].head.block_max + quater;
646 while (lookahead_item)
648 char *dst_item = lookahead_item;
652 (*b->method->compare_item)(max_item, lookahead_item) <= 0)
657 if (!*lookahead_mode)
659 yaz_log (LOG_WARN, "Inconsistent register (2)");
662 else if (!half1 && dst > cut)
664 char *dst_item_0 = dst_item;
665 half1 = dst; /* candidate for splitting */
667 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
669 cut_item_size = dst_item - dst_item_0;
670 memcpy (cut_item_buf, dst_item_0, cut_item_size);
675 (*b->method->code_item)(ISAMC_ENCODE, c2, &dst, &dst_item);
684 dst_item = lookahead_item;
685 if (!(*stream->read_item)(stream->clientData, &dst_item,
692 new_size = dst - dst_buf;
693 if (p && p->cat != b->no_cat-1 &&
694 new_size > b->file[p->cat].head.block_max)
696 /* non-btree block will be removed */
699 /* delete it too!! */
700 p = 0; /* make a new one anyway */
703 { /* must create a new one */
705 for (i = 0; i < b->no_cat; i++)
706 if (new_size <= b->file[i].head.block_max)
712 if (new_size > b->file[p->cat].head.block_max)
715 char *cut_item = cut_item_buf;
721 p->size = half1 - dst_buf;
722 memcpy (p->bytes, dst_buf, half1 - dst_buf);
725 *sp2 = new_leaf (b, p->cat);
727 (*b->method->code_reset)(c2);
729 first_dst = (*sp2)->bytes;
731 (*b->method->code_item)(ISAMC_ENCODE, c2, &first_dst, &cut_item);
733 memcpy (first_dst, half2, dst - half2);
735 (*sp2)->size = (first_dst - (*sp2)->bytes) + (dst - half2);
738 memcpy (sub_item, cut_item_buf, cut_item_size);
739 *sub_size = cut_item_size;
743 memcpy (p->bytes, dst_buf, dst - dst_buf);
746 (*b->method->code_stop)(ISAMC_DECODE, c1);
747 (*b->method->code_stop)(ISAMC_ENCODE, c2);
752 int insert_sub (ISAMB b, struct ISAMB_block **p, void *new_item,
755 struct ISAMB_block **sp,
756 void *sub_item, int *sub_size,
759 if (!*p || (*p)->leaf)
760 return insert_leaf (b, p, new_item, mode, stream, sp, sub_item,
763 return insert_int (b, *p, new_item, mode, stream, sp, sub_item,
767 int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
769 char item_buf[DST_ITEM_MAX];
781 (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
786 more = (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
789 struct ISAMB_block *p = 0, *sp = 0;
790 char sub_item[DST_ITEM_MAX];
794 p = open_block (b, pos);
795 more = insert_sub (b, &p, item_buf, &i_mode, stream, &sp,
796 sub_item, &sub_size, 0);
798 { /* increase level of tree by one */
799 struct ISAMB_block *p2 = new_int (b, p->cat);
800 char *dst = p2->bytes + p2->size;
802 encode_ptr (&dst, p->pos);
803 assert (sub_size < 20);
804 encode_ptr (&dst, sub_size);
805 memcpy (dst, sub_item, sub_size);
807 encode_ptr (&dst, sp->pos);
809 p2->size = dst - p2->bytes;
810 pos = p2->pos; /* return new super page */
815 pos = p->pos; /* return current one (again) */
821 ISAMB_PP isamb_pp_open_x (ISAMB isamb, ISAMB_P pos, int *level)
823 ISAMB_PP pp = xmalloc (sizeof(*pp));
826 pp->block = xmalloc (10 * sizeof(*pp->block));
834 struct ISAMB_block *p = open_block (isamb, pos);
835 char *src = p->bytes + p->offset;
836 pp->block[pp->level] = p;
838 pp->total_size += p->size;
844 decode_ptr (&src, &pos);
845 p->offset = src - p->bytes;
848 pp->block[pp->level+1] = 0;
854 ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
856 return isamb_pp_open_x (isamb, pos, 0);
859 void isamb_pp_close_x (ISAMB_PP pp, int *size, int *blocks)
865 *size = pp->total_size;
867 *blocks = pp->no_blocks;
868 for (i = 0; i <= pp->level; i++)
869 close_block (pp->isamb, pp->block[i]);
874 int isamb_block_info (ISAMB isamb, int cat)
876 if (cat >= 0 && cat < isamb->no_cat)
877 return isamb->file[cat].head.block_size;
881 void isamb_pp_close (ISAMB_PP pp)
883 isamb_pp_close_x (pp, 0, 0);
886 int isamb_pp_read (ISAMB_PP pp, void *buf)
890 struct ISAMB_block *p = pp->block[pp->level];
894 while (p->offset == p->size)
897 while (p->offset == p->size)
901 close_block (pp->isamb, pp->block[pp->level]);
902 pp->block[pp->level] = 0;
904 p = pp->block[pp->level];
905 assert (!p->leaf); /* must be int */
907 src = p->bytes + p->offset;
909 decode_ptr (&src, &item_len);
911 decode_ptr (&src, &pos);
913 p->offset = src - (char*) p->bytes;
919 pp->block[pp->level] = p = open_block (pp->isamb, pos);
921 pp->total_size += p->size;
924 if (p->leaf) /* leaf */
928 src = p->bytes + p->offset;
929 decode_ptr (&src, &pos);
930 p->offset = src - (char*) p->bytes;
934 assert (p->offset < p->size);
936 src = p->bytes + p->offset;
937 (*pp->isamb->method->code_item)(ISAMC_DECODE, p->decodeClientData,
939 p->offset = src - (char*) p->bytes;
943 int isamb_pp_num (ISAMB_PP pp)