-/*
- * Copyright (c) 1996-1998, Index Data.
- * See the file LICENSE for details.
- * Heikki Levanto
- *
- * $Id: merge-d.c,v 1.27 2002-07-12 18:12:21 heikki Exp $
- *
- * bugs
- * sinleton-bit has to be in the high end, not low, so as not to confuse
- * ordinary small numbers, like in the next pointer..
- *
- * missing
- *
- * optimize
- * - study and optimize block sizes (later)
- * - find a way to decide the size of an empty diffblock (after merge)
- * - On allocating more blocks (in append and merge), check the order of
- * blocks, and if needed, swap them.
- * - Write a routine to save/load indexes into a block, save only as many
- * bytes as needed (size, diff, diffindexes)
- *
- *
- * caveat
- * There is a confusion about the block addresses. cat or type is the category,
- * pos or block is the block number. pp structures keep these two separate,
- * and combine when saving the pp. The next pointer in the pp structure is
- * also a combined address, but needs to be combined every time it is needed,
- * and separated when the partss are needed... This is done with the isamd_
- * _block, _type, and _addr macros. The _addr takes block and type as args,
- * in that order. This conflicts with the order these are often mentioned in
- * the debug log calls, and other places, leading to small mistakes here
- * and there.
- *
- * Needs cleaning! The way diff blocks are handled in append and reading is
- * quite different, and likely to give maintenance problems.
- *
- * log levels (set isamddebug=x in zebra.cfg (or what ever cfg file you use) )
- * 0 = no logging. Default
- * 1 = no logging here. isamd logs overall statistics
- * 2 = Each call to isamd_append with start address and no more
- * 3 = Start and type of append, start of merge, and result of append
- * 4 = Block allocations
- * 5 = Block-level operations (read/write)
- * 6 = Details about diff blocks etc.
- * 7 = Log each record as it passes the system (once)
- * 8 = Log raw and (de)coded data
- * 9 = Anything else that may be useful
- * .. = Anything needed to hunt a specific bug
- * (note that all tests in the code are like debug>3, which means 4 or above!)
- *
- * Design for the new and improved isamd
- * Key points:
- * - The first block is only diffs, no straight data
- * - Additional blocks are straight data
- * - When a diff block gets filled up, a data block is created by
- * merging the diffs with the data
- *
- * Structure
- * - Isamd_pp: buffer for diffs and for data
- * keep both pos, type, and combined address
- * routine to set the address
- * - diffbuf: lengths as short ints, or bytes for small blocks
- * - keys are of key_struct, not just a number of bytes.
- *
- * Routines
- * - isamd_append
- * - create_new_block if needed
- * - append_diffs
- * - load_diffs
- * - get diffend, start encoding
- * - while input data
- * - encode it
- * - if no room, then realloc block in larger size
- * - if still no room, merge and exit
- * - append in the block
- *
- * - merge
- * - just as before, except that merges also input data directly
- * - writes into new data blocks
- *
- *
- * - isamd.c: load firstpp, load datablock
- * save firstpp, save datablock
- * - Readlength, writelength - handling right size of len fields
- * - isamd_read_main_item: take also a merge input structure, and merge it too
- * - prefilter: cache two inputs, and check if they cancel.
- * - single-item optimization
- *
- * questions: Should we realloc firstblocks in a different size as the main
- * blocks. Makes a sideways seek, which is bound to be slowe. But saves some
- * update time. Compromise: alloc the first one in the size of the datablock,
- * but increase if necessary. Large blocks get a large diff, ok. Small ones
- * may get an extra seek in read, but save merges.
- */
+/* $Id: merge-d.c,v 1.29 2002-11-26 22:18:34 adam Exp $
+ Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002
+ Index Data Aps
+
+This file is part of the Zebra server.
+
+Zebra is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 2, or (at your option) any later
+version.
+
+Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with Zebra; see the file LICENSE.zebra. If not, write to the
+Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+02111-1307, USA.
+*/
+
+
#define NEW_ISAM_D 1 /* not yet ready to delete the old one! */
int difftype;
};
-#define DT_NONE 0 // no diff, marks end of sequence
-#define DT_DIFF 1 // ordinarry diff
-#define DT_MAIN 2 // main data
-#define DT_INPU 3 // input data to be merged
-#define DT_DONE 4 // done with all input here
+#define DT_NONE 0 /* no diff, marks end of sequence */
+#define DT_DIFF 1 /* ordinarry diff */
+#define DT_MAIN 2 /* main data */
+#define DT_INPU 3 /* input data to be merged */
+#define DT_DONE 4 /* done with all input here */
if (0==pp->diffinfo[i].maxidx)
{
- if (pp->is->method->debug > 5) //!!! 4
+ if (pp->is->method->debug > 5) /* !!! 4 */
logf(LOG_LOG,"isamd_getDiffInfo:End mark at ix=%d n=%d",
diffidx, i);
return; /* end marker */
; /* find last diff */
if (p_key)
{ /* we have an extra item to inject into the merge */
- if (pp->is->method->debug >9) //!!!!!
+ if (pp->is->method->debug >9) /* !!!!! */
logf(LOG_LOG,"isamd_read_item: going to merge with %d.%d",
p_key->sysno, p_key->seqno);
pp->diffinfo[i].key = *p_key; /* the key merge could not handle */
/* set up diffs as they should be for reading */
diffidx = ISAMD_BLOCK_OFFSET_1;
- //readpp->diffbuf=readpp->buf; // diffinfo has to duplicate it!
- //getDiffInfo(readpp); // first read will make the diffinfo, at init
if (readpp->is->method->debug >4)
logf(LOG_LOG,"isamd_merge: f=%d=%d:%d n=%d=%d:%d",
} /* while read */
-// firstpp->diffs=0;
-
-
isamd_reduceblock(pp); /* reduce size if possible */
if (0==firstpp->next)
firstpp->next = isamd_addr(pp->pos,pp->cat);
diffidx+=sizeof(int); /* difflen will be stored here */
/* read first input */
- //i_ptr = i_item; //!!!
i_more = filter_read(filt, &i_key, &i_mode);
/* i_more = (*data->read_item)(data->clientData, &i_ptr, &i_mode); */
{ /* max size - can't help, need to merge it */
if (is->method->debug >7)
logf(LOG_LOG,"isamd_appd: need to merge");
- if (is->method->debug >9) //!!!!!
+ if (is->method->debug >9) /* !!!!! */
logf(LOG_LOG,"isamd_appd: going to merge with m=%d %d.%d",
i_mode, i_key.sysno, i_key.seqno);
merge_rc = merge (firstpp, &i_key, filt, dictentry, dictlen);
/*
* $Log: merge-d.c,v $
- * Revision 1.27 2002-07-12 18:12:21 heikki
+ * Revision 1.29 2002-11-26 22:18:34 adam
+ * Remove // comments
+ *
+ * Revision 1.28 2002/08/02 19:26:56 adam
+ * Towards GPL
+ *
+ * Revision 1.27 2002/07/12 18:12:21 heikki
* Isam-D now stores small entries directly in the dictionary.
* Needs more tuning and cleaning...
*