* may make sense to reserve some extra space...
*/
-ISAMC_P isamh_append (ISAMH is, ISAMH_P ipos, ISAMH_I data)
+
+static void isamh_reduceblock(ISAMH is, ISAMH_PP pp, int numKeys)
{
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_reduce: block p=%d c=%d o=%d nk=%d ",
+ pp->pos, pp->cat, pp->offset, numKeys);
+ if (pp->pos != 0)
+ return; /* already allocated in some size */
+ while ( ( pp->cat > 0 ) &&
+ ( pp->offset < is->method->filecat[pp->cat-1].bsize) &&
+ ( numKeys < is->method->filecat[pp->cat-1].mblocks) )
+ pp->cat--;
+ pp->pos = isamh_alloc_block(is,pp->cat) ;
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_reduced block p=%d to c=%d o=%d nk=%d bs=%d",
+ pp->pos, pp->cat, pp->offset, numKeys,
+ is->method->filecat[pp->cat].bsize);
+} /* reduceblock */
- ISAMH_PP pp;
+ISAMC_P isamh_append (ISAMH is, ISAMH_P ipos, ISAMH_I data)
+{
+
+ ISAMH_PP pp; /* always the last pp in the chain */
+ ISAMH_PP firstpp; /* always the first one in the chain, may ==pp */
+ ISAMH_PP prevpp; /* the one that points to pp, may be null or ==firstpp */
+ /* needed to postpone the writing of its next field until */
+ /* pp itself has been categorized */
char i_item[128];
char *i_item_ptr;
int i_more=1, i_mode;
char *bufptr;
int codelen;
- ISAMH_PP firstpp;
void *r_clientData; /* encode client data */
int newblock;
int newcat;
int maxkeys;
int maxsize;
int retval;
+ int maxcat;
pp = firstpp = isamh_pp_open (is, ipos);
+ prevpp =0; /* only used when new blocks allocated */
+
assert (*is->method->code_reset);
+ maxcat=0; /* find the largest block size for default allocation */
+ for ( newcat=0; is->method->filecat[newcat].mblocks > 0; newcat++)
+ if ( is->method->filecat[newcat].bsize >
+ is->method->filecat[maxcat].bsize)
+ maxcat = newcat;
+
if ( 0==ipos)
{ /* new block */
- pp->cat=0; /* start small... */
- pp->pos = isamh_alloc_block(is,pp->cat);
+ pp->cat=maxcat; /* start large... */
+ pp->pos = 0; /* not allocated yet */
pp->size= pp->offset = ISAMH_BLOCK_OFFSET_1 ;
+ pp->buf=xrealloc(pp->buf,is->method->filecat[maxcat].bsize);
r_clientData = (*is->method->code_start)(ISAMH_ENCODE);
if (pp->is->method->debug > 2)
- logf(LOG_LOG,"isamh_append: starting with new block %d",pp->pos);
+ logf(LOG_LOG,"isamh_append: starting with new block");
}
else
{ /* existing block */
if (isamh_block(firstpp->lastblock) == firstpp->pos)
+ /*!!! TODO: BUG: Compare whole addresses !!! (later) */
{ /* only one block, we have it already */
pp->offset=ISAMH_BLOCK_OFFSET_1;
if (pp->is->method->debug > 2)
if ( pp->offset + codelen > maxsize )
{ /* oops, block full, do something */
- newcat = pp->cat;
+ newcat = maxcat; /* start with a large block again */
maxkeys = is->method->filecat[pp->cat].mblocks; /* max keys */
if (pp->is->method->debug > 2)
logf(LOG_LOG,"isamh_append: need new block: %d > %d (k:%d/%d)",
pp->offset + codelen, maxsize, firstpp->numKeys,maxkeys );
- if ( (maxkeys>0) && (firstpp->numKeys > maxkeys) )
- { /* time to increase block size */
- newcat++;
- maxsize = is->method->filecat[newcat].bsize;
- pp->buf=xrealloc(pp->buf,maxsize);
- if (pp->is->method->debug > 2)
- logf(LOG_LOG,"isamh_append: increased to cat %d ",newcat);
- }
- newblock = isamh_alloc_block(is,newcat);
- pp->next = isamh_addr(newblock,newcat);
- if (firstpp!=pp)
- { /* not first block, write to disk already now */
- isamh_buildlaterblock(pp);
- isamh_write_block(is,pp->cat,pp->pos,pp->buf);
+ newblock = 0;
+ pp->next = 0;
+
+ /* Four possibilities: */
+ if (prevpp!=0)
+ { /* 1: we have a prevpp that can go on the disk */
+ /* reduce pp, set next ptr, and store block */
+ /* set pp up as new last block, and remember the just */
+ /* filled as (pp) the new prev */
+ assert(pp!=firstpp);
+ isamh_reduceblock(is,pp,firstpp->numKeys);
+ prevpp->next=isamh_addr(pp->pos,pp->cat);
+ isamh_buildlaterblock(prevpp);
+ isamh_write_block(is,prevpp->cat,prevpp->pos,prevpp->buf);
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_append N1: Wrote prevpp (%d:%d) -> %d:%d",
+ prevpp->pos, prevpp->cat, pp->pos, pp->cat);
+ isamh_pp_close(prevpp); /* it's done its job */
+ prevpp = pp;
+ pp=isamh_pp_open(is,isamh_addr(0,maxcat)); /* start a large one */
+ pp->size=pp->offset=ISAMH_BLOCK_OFFSET_N ;
+ pp->next=0;
+ pp->lastblock=0;
+ }
+ else if ( (firstpp!=pp) && (firstpp->next != 0))
+ { /* 2: we are working at end of list, but have no prevpp */
+ /* some block (already on disk) points to pp */
+ /* set the newly filled block as prev, don't save yet */
+ /* allocate new pp */
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_append N2: set up a new prevpp (%d:%d)",
+ pp->pos, pp->cat);
+ prevpp = pp;
+ pp=isamh_pp_open(is,isamh_addr(0,maxcat)); /* start a large one */
+ pp->size=pp->offset=ISAMH_BLOCK_OFFSET_N ;
+ pp->next=0;
+ pp->lastblock=0;
+ }
+ else if ( (firstpp!=pp) && (firstpp->next==0))
+ { /* 3: we have earlier allocated pp as the second block */
+ /* reduce it to get its address. Set first->next to it */
+ /* move it to prevpp, and create a new pp */
+ isamh_reduceblock(is,pp,firstpp->numKeys);
+ firstpp->next=isamh_addr(pp->pos,pp->cat);
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_append N3: set up a new firstpp->next (%d:%d)",
+ pp->pos, pp->cat);
+ prevpp=pp;
+ pp=isamh_pp_open(is,isamh_addr(0,maxcat)); /* start a large one */
+ pp->size=pp->offset=ISAMH_BLOCK_OFFSET_N ;
+ pp->next=0;
+ pp->lastblock=0;
}
else
- { /* we had only one block, allocate a second buffer */
- pp = isamh_pp_open(is,0);
+ { /* 4: firstpp itself has got full. */
+ /* allocate a new pp for it, store nothing */
+ assert(firstpp==pp);
+ assert(firstpp->next==0);
+ if (pp->is->method->debug > 2)
+ logf(LOG_LOG,"isamh_append N4: allocated new pp for full first (%d:%d)",
+ firstpp->pos, firstpp->cat);
+ pp=isamh_pp_open(is,isamh_addr(0,maxcat)); /* start a large one */
+ pp->size=pp->offset=ISAMH_BLOCK_OFFSET_N ;
+ pp->next=0;
+ pp->lastblock=0;
}
- pp->cat = newcat;
- pp->pos = newblock;
-
+
+ maxsize = is->method->filecat[pp->cat].bsize;
pp->size=pp->offset=ISAMH_BLOCK_OFFSET_N ;
pp->next=0;
pp->lastblock=0;
if (pp->is->method->debug > 2)
- logf(LOG_LOG,"isamh_append: got a new block %d:%d",pp->cat,pp->pos);
+ logf(LOG_LOG,"isamh_append: got a new block c=%d p=%d",pp->cat,pp->pos);
+
/* reset the encoding, and code again */
(*is->method->code_reset)(r_clientData);
} /* while */
+ isamh_reduceblock(is,pp,firstpp->numKeys);
+ /* may be the same as firstpp! */
+
+ if (prevpp)
+ { /* Write the prev block we have been holding off */
+ assert(prevpp->pos);
+ prevpp->next = isamh_addr(pp->pos, pp->cat);
+ isamh_buildlaterblock(prevpp);
+ isamh_write_block(is,prevpp->cat,prevpp->pos,prevpp->buf);
+ if (firstpp->next==0) /* can happen if extending many blocks */
+ firstpp->next=isamh_addr(prevpp->pos,prevpp->cat);
+ isamh_pp_close(prevpp);
+ }
/* Write the last (partial) block, if needed. */
if (pp!=firstpp)
{
pp->next=0; /* just to be sure */
+ if (firstpp->next==0)
+ firstpp->next=isamh_addr(pp->pos,pp->cat);
isamh_buildlaterblock(pp);
isamh_write_block(is,pp->cat,pp->pos,pp->buf);
}
/* update first block and write it */
firstpp->lastblock = isamh_addr(pp->pos,pp->cat);
+ isamh_reduceblock(is,firstpp,firstpp->numKeys);
isamh_buildfirstblock(firstpp);
isamh_write_block(is,firstpp->cat,firstpp->pos,firstpp->buf);
/* get return value (before it disappears at close! */
retval = isamh_addr(firstpp->pos,firstpp->cat);
- isamh_pp_close(firstpp);
+ isamh_pp_close(firstpp);
return retval;
/*
* $Log: merge.c,v $
- * Revision 1.18 1999-07-13 15:24:50 heikki
- * Removed the one-block append, it had a serious flaw.
+ * Revision 1.19 1999-07-14 12:12:07 heikki
+ * Large-block isam-h (may not work too well... Abandoning for isam-d)
+ *
+ * Revision 1.17 1999/07/13 14:22:17 heikki
+ * Better allocation strategy in isamh_merge
*
* Revision 1.16 1999/07/08 14:23:27 heikki
* Fixed a bug in isamh_pp_read and cleaned up a bit
projects / idzebra-moved-to-github.git / blobdiff