-/* $Id: isamb.c,v 1.57 2004-09-03 14:59:49 heikki Exp $
+/* $Id: isamb.c,v 1.58 2004-09-09 10:08:05 heikki Exp $
Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003,2004
Index Data Aps
zint skipped_nodes[ISAMB_MAX_LEVEL]; /* [0]=skipped leaves, 1=higher etc */
zint accessed_nodes[ISAMB_MAX_LEVEL]; /* nodes we did not skip */
struct ISAMB_block **block;
+ int scope; /* on what level we forward */
};
return pos;
}
-ISAMB_PP isamb_pp_open_x (ISAMB isamb, ISAMB_P pos, int *level)
+ISAMB_PP isamb_pp_open_x (ISAMB isamb, ISAMB_P pos, int *level, int scope)
{
ISAMB_PP pp = xmalloc (sizeof(*pp));
int i;
pp->no_blocks = 0;
pp->skipped_numbers=0;
pp->returned_numbers=0;
+ pp->scope=scope;
for (i=0;i<ISAMB_MAX_LEVEL;i++)
pp->skipped_nodes[i] = pp->accessed_nodes[i]=0;
while (1)
return pp;
}
-ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
+ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos, int scope)
{
- return isamb_pp_open_x (isamb, pos, 0);
+ return isamb_pp_open_x (isamb, pos, 0, scope);
}
void isamb_pp_close_x (ISAMB_PP pp, int *size, int *blocks)
isamb_dump_r(b, pos, pr, 0);
}
-#if 0
-/* Old isamb_pp_read that Adam wrote, kept as a reference in case we need to
- debug the more complex pp_read that also forwards. May be deleted near end
- of 2004, if it has not shown to be useful */
-
-
-int isamb_pp_read (ISAMB_PP pp, void *buf)
-{
- char *dst = buf;
- char *src;
- struct ISAMB_block *p = pp->block[pp->level];
- if (!p)
- return 0;
-
- while (p->offset == p->size)
- {
- int pos, item_len;
- while (p->offset == p->size)
- {
- if (pp->level == 0)
- return 0;
- close_block (pp->isamb, pp->block[pp->level]);
- pp->block[pp->level] = 0;
- (pp->level)--;
- p = pp->block[pp->level];
- assert (!p->leaf);
- }
- src = p->bytes + p->offset;
-
- decode_ptr (&src, &item_len);
- src += item_len;
- decode_ptr (&src, &pos);
-
- p->offset = src - (char*) p->bytes;
-
- ++(pp->level);
-
- while (1)
- {
- pp->block[pp->level] = p = open_block (pp->isamb, pos);
-
- pp->total_size += p->size;
- pp->no_blocks++;
-
- if (p->leaf)
- {
- break;
- }
- src = p->bytes + p->offset;
- decode_ptr (&src, &pos);
- p->offset = src - (char*) p->bytes;
- pp->level++;
- }
- }
- assert (p->offset < p->size);
- assert (p->leaf);
- src = p->bytes + p->offset;
- (*pp->isamb->method->codec.code_item)(ISAMC_DECODE, p->decodeClientData,
- &dst, &src);
- p->offset = src - (char*) p->bytes;
- /* key_logdump_txt(LOG_DEBUG,buf, "isamb_pp_read returning 1"); */
- return 1;
-}
-
-#else
int isamb_pp_read (ISAMB_PP pp, void *buf)
{
return isamb_pp_forward(pp, buf, 0);
}
-#endif
-#define NEW_FORWARD 1
-
-#if NEW_FORWARD == 1
static int isamb_pp_on_right_node(ISAMB_PP pp, int level, const void *untilbuf)
{ /* looks one node higher to see if we should be on this node at all */
(*pp->isamb->method->codec.log_item)(LOG_DEBUG,src,"on_leaf: value");
#endif
cmp=(*pp->isamb->method->compare_item)(untilbuf,src);
- if (cmp<2) {
+ if (cmp<pp->scope) { /* cmp<2 */
#if ISAMB_DEBUG
logf(LOG_DEBUG,"isamb_pp_on_right returning true "
"cmp=%d lev=%d ofs=%d",cmp,level,p->offset);
dst=buf;
(*pp->isamb->method->codec.decode)(p->decodeClientData,&dst, &src);
p->offset = src - (char*) p->bytes;
- /*
#if ISAMB_DEBUG
(*pp->isamb->method->codec.log_item)(LOG_DEBUG, buf, "read_on_leaf returning 1");
#endif
-*/
pp->returned_numbers++;
return 1;
} /* read_on_leaf */
return 0;
/* FIXME - this is an extra function call, inline the read? */
cmp=(*pp->isamb->method->compare_item)(untilbuf,buf);
- if (cmp <2){ /* found a good one */
+ if (cmp <pp->scope){ /* cmp<2 found a good one */
#if ISAMB_DEBUG
if (skips)
logf(LOG_DEBUG, "isam_pp_fwd_on_leaf skipped %d items",skips);
cmp=(*pp->isamb->method->compare_item)(untilbuf,src);
src+=item_len;
decode_ptr(&src,&nxtpos);
- if (cmp<2)
+ if (cmp<pp->scope) /* cmp<2 */
{
#if ISAMB_DEBUG
logf(LOG_DEBUG,"isamb_pp_forward_unode returning a hit "
struct ISAMB_block *p = pp->block[pp->level];
assert(p->leaf);
logf(LOG_DEBUG,"isamb_pp_forward starting "
- "at level %d node %d ofs=%d sz=%d u=%p",
- pp->level, p->pos, p->offset, p->size,untilbuf);
+ "at level %d node %d ofs=%d sz=%d u=%p sc=%d",
+ pp->level, p->pos, p->offset, p->size,untilbuf, scope);
#endif
if (untilbuf) {
if (isamb_pp_forward_on_leaf( pp, buf, untilbuf)) {
}
} /* isam_pp_forward (new version) */
-#elif NEW_FORWARD == 0
-
-int isamb_pp_forward (ISAMB_PP pp, void *buf, const void *untilbuf)
-{
- /* pseudocode:
- * while 1
- * while at end of node
- * climb higher. If out, return 0
- * while not on a leaf (and not at its end)
- * decode next
- * if cmp
- * descend to node
- * decode next
- * if cmp
- * return 1
- */
- /*
- * The upper nodes consist of a sequence of nodenumbers and keys
- * When opening a block, the first node number is read in, and
- * offset points to the first key, which is the upper limit of keys
- * in the node just read.
- */
- char *dst = buf;
- const char *src;
- struct ISAMB_block *p = pp->block[pp->level];
- int cmp;
- int item_len;
- int pos;
- int nxtpos;
- int descending=0; /* used to prevent a border condition error */
- if (!p)
- return 0;
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward starting [%p] p=%d",pp,p->pos);
-
- (*pp->isamb->method->codec.log_item)(LOG_DEBUG, untilbuf, "until");
- (*pp->isamb->method->codec.log_item)(LOG_DEBUG, buf, "buf");
-#endif
-
- while (1)
- {
- while ( (p->offset == p->size) && !descending )
- { /* end of this block - climb higher */
- assert (p->offset <= p->size);
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward climbing from l=%d",
- pp->level);
-#endif
- if (pp->level == 0)
- {
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward returning 0 at root");
-#endif
- return 0; /* at end of the root, nothing left */
- }
- close_block(pp->isamb, pp->block[pp->level]);
- pp->block[pp->level]=0;
- (pp->level)--;
- p=pp->block[pp->level];
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward climbed to node %d off=%d",
- p->pos, p->offset);
-#endif
- assert(!p->leaf);
- assert(p->offset <= p->size);
- /* skip the child we have handled */
- if (p->offset != p->size)
- {
- src = p->bytes + p->offset;
- decode_ptr(&src, &item_len);
-#if ISAMB_DEBUG
- (*pp->isamb->method->codec.log_item)(LOG_DEBUG, src,
- " isamb_pp_forward "
- "climb skipping old key");
-#endif
- src += item_len;
- decode_ptr(&src,&pos);
- p->offset = src - (char*) p->bytes;
- break; /* even if this puts us at the end of the block, we
- need to descend to the last pos. UGLY coding,
- clean up some day */
- }
- }
- if (!p->leaf)
- {
- src = p->bytes + p->offset;
- if (p->offset == p->size)
- cmp=-2 ; /* descend to the last node, as we have
- no value to cmp */
- else
- {
- decode_ptr(&src, &item_len);
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward (B) on a high node. "
- "ofs=%d sz=%d nxtpos=%d ",
- p->offset,p->size,pos);
- (*pp->isamb->method->codec.log_item)(LOG_DEBUG, src, "");
-#endif
- if (untilbuf)
- cmp=(*pp->isamb->method->compare_item)(untilbuf,src);
- else
- cmp=-2;
- src += item_len;
- decode_ptr(&src,&nxtpos);
- }
- if (cmp<2)
- {
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isambb_pp_forward descending l=%d p=%d ",
- pp->level, pos);
-#endif
- descending=1; /* prevent climbing for a while */
- ++(pp->level);
- p = open_block(pp->isamb,pos);
- pp->block[pp->level] = p ;
- pp->total_size += p->size;
- (pp->accessed_nodes[pp->maxlevel - pp->level])++;
- pp->no_blocks++;
- if ( !p->leaf)
- { /* block starts with a pos */
- src = p->bytes + p->offset;
- decode_ptr(&src,&pos);
- p->offset=src-(char*) p->bytes;
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward: block %d starts with %d",
- p->pos, pos);
-#endif
- }
- } /* descend to the node */
- else
- { /* skip the node */
- p->offset = src - (char*) p->bytes;
- pos=nxtpos;
- (pp->skipped_nodes[pp->maxlevel - pp->level -1])++;
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,
- "isamb_pp_forward: skipping block on level %d, noting "
- "on %d (%d)",
- pp->level, pp->maxlevel - pp->level-1 ,
- pp->skipped_nodes[pp->maxlevel - pp->level-1 ]);
-#endif
- /* 0 is always leafs, 1 is one level above leafs etc, no
- * matter how high tree */
- }
- } /* not on a leaf */
- else
- { /* on a leaf */
- if (p->offset == p->size) {
- descending = 0;
- }
- else
- {
- assert (p->offset < p->size);
- src = p->bytes + p->offset;
- dst=buf;
- (*pp->isamb->method->codec.decode)(p->decodeClientData,
- &dst, &src);
- p->offset = src - (char*) p->bytes;
- if (untilbuf)
- cmp=(*pp->isamb->method->compare_item)(untilbuf,buf);
- else
- cmp=-2;
-#if ISAMB_DEBUG
- logf(LOG_DEBUG,"isamb_pp_forward on a leaf. cmp=%d",
- cmp);
- (*pp->isamb->method->codec.log_item)(LOG_DEBUG, buf, "");
-#endif
- if (cmp <2)
- {
-#if ISAMB_DEBUG
- if (untilbuf)
- {
- (*pp->isamb->method->codec.log_item)(
- LOG_DEBUG, buf, "isamb_pp_forward returning 1");
- }
- else
- {
- (*pp->isamb->method->codec.log_item)(
- LOG_DEBUG, buf, "isamb_pp_read returning 1 (fwd)");
- }
-#endif
- pp->returned_numbers++;
- return 1;
- }
- else
- pp->skipped_numbers++;
- }
- } /* leaf */
- } /* main loop */
-}
-
-#elif NEW_FORWARD == 2
-
-int isamb_pp_forward (ISAMB_PP pp, void *buf, const void *untilb)
-{
- char *dst = buf;
- const char *src;
- struct ISAMB_block *p = pp->block[pp->level];
- if (!p)
- return 0;
-
-again:
- while (p->offset == p->size)
- {
- int pos, item_len;
- while (p->offset == p->size)
- {
- if (pp->level == 0)
- return 0;
- close_block (pp->isamb, pp->block[pp->level]);
- pp->block[pp->level] = 0;
- (pp->level)--;
- p = pp->block[pp->level];
- assert (!p->leaf);
- }
-
- assert(!p->leaf);
- src = p->bytes + p->offset;
-
- decode_ptr (&src, &item_len);
- src += item_len;
- decode_ptr (&src, &pos);
-
- p->offset = src - (char*) p->bytes;
-
- src = p->bytes + p->offset;
-
- while(1)
- {
- if (!untilb || p->offset == p->size)
- break;
- assert(p->offset < p->size);
- decode_ptr (&src, &item_len);
- if ((*pp->isamb->method->compare_item)(untilb, src) <= 1)
- break;
- src += item_len;
- decode_ptr (&src, &pos);
- p->offset = src - (char*) p->bytes;
- }
-
- pp->level++;
-
- while (1)
- {
- pp->block[pp->level] = p = open_block (pp->isamb, pos);
-
- pp->total_size += p->size;
- pp->no_blocks++;
-
- if (p->leaf)
- {
- break;
- }
-
- src = p->bytes + p->offset;
- while(1)
- {
- decode_ptr (&src, &pos);
- p->offset = src - (char*) p->bytes;
-
- if (!untilb || p->offset == p->size)
- break;
- assert(p->offset < p->size);
- decode_ptr (&src, &item_len);
- if ((*pp->isamb->method->compare_item)(untilb, src) <= 1)
- break;
- src += item_len;
- }
- pp->level++;
- }
- }
- assert (p->offset < p->size);
- assert (p->leaf);
- while(1)
- {
- char *dst0 = dst;
- src = p->bytes + p->offset;
- (*pp->isamb->method->codec.decode)(p->decodeClientData, &dst, &src);
- p->offset = src - (char*) p->bytes;
- if (!untilb || (*pp->isamb->method->compare_item)(untilb, dst0) <= 1)
- break;
- dst = dst0;
- if (p->offset == p->size) goto again;
- }
- /* key_logdump_txt(LOG_DEBUG,buf, "isamb_pp_read returning 1"); */
- return 1;
-}
-
-#endif
-
void isamb_pp_pos( ISAMB_PP pp, double *current, double *total )
{ /* return an estimate of the current position and of the total number of */
/* occureences in the isam tree, based on the current leaf */