X-Git-Url: http://git.indexdata.com/?a=blobdiff_plain;f=isamb%2Fisamb.c;h=2ac59fb7c94de153cdedc72794d92b7fb3057ed9;hb=0d4ce8fe167ca3df0c216179de0a2e9d22ce3a6a;hp=4302a53113ebaa0c3e909b6cbf701c528ac9a4d0;hpb=2e6e4817f094605bbd3455b95ac5fc69920dcc34;p=idzebra-moved-to-github.git

diff --git a/isamb/isamb.c b/isamb/isamb.c
index 4302a53..2ac59fb 100644
--- a/isamb/isamb.c
+++ b/isamb/isamb.c
@@ -1,9 +1,26 @@
-/*
- *  Copyright (c) 1995-1998, Index Data.
- *  See the file LICENSE for details.
- *
- *  $Id: isamb.c,v 1.9 2002-04-23 17:56:54 adam Exp $
- */
+/* $Id: isamb.c,v 1.23 2003-03-02 23:12:50 adam Exp $
+   Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002,2003
+   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.
+*/
+
+#include <string.h>
 #include <yaz/xmalloc.h>
 #include <yaz/log.h>
 #include <isamb.h>
@@ -14,6 +31,7 @@ struct ISAMB_head {
     int last_block;
     int block_size;
     int block_max;
+    int free_list;
 };
 
 #define ISAMB_DATA_OFFSET 3
@@ -23,11 +41,22 @@ struct ISAMB_head {
 /* approx 2*4 K + max size of item */
 #define DST_BUF_SIZE 8448
 
+#define ISAMB_CACHE_ENTRY_SIZE 4096
+
+struct ISAMB_cache_entry {
+    ISAMB_P pos;
+    char *buf;
+    int dirty;
+    int hits;
+    struct ISAMB_cache_entry *next;
+};
+
 
 struct ISAMB_file {
     BFile bf;
     int head_dirty;
     struct ISAMB_head head;
+    struct ISAMB_cache_entry *cache_entries;
 };
 
 struct ISAMB_s {
@@ -36,23 +65,31 @@ struct ISAMB_s {
 
     struct ISAMB_file *file;
     int no_cat;
+    int cache; /* 0=no cache, 1=use cache, -1=dummy isam (for testing only) */
+    int log_io;        /* log level for bf_read/bf_write calls */
+    int log_freelist;  /* log level for freelist handling */
 };
 
 struct ISAMB_block {
-    int pos;
+    ISAMB_P pos;
     int cat;
     int size;
     int leaf;
     int dirty;
+    int deleted;
     int offset;
     char *bytes;
     unsigned char *buf;
     void *decodeClientData;
+    int log_rw;
 };
 
 struct ISAMB_PP_s {
     ISAMB isamb;
+    ISAMB_P pos;
     int level;
+    int total_size;
+    int no_blocks;
     struct ISAMB_block **block;
 };
 
@@ -68,50 +105,158 @@ void decode_ptr (char **src, int *pos)
     (*src) += sizeof(*pos);
 }
 
-ISAMB isamb_open (BFiles bfs, const char *name, int writeflag, ISAMC_M method)
+ISAMB isamb_open (BFiles bfs, const char *name, int writeflag, ISAMC_M method,
+                  int cache)
 {
     ISAMB isamb = xmalloc (sizeof(*isamb));
-    int i, b_size = 64;
+    int i, b_size = 32;
 
     isamb->bfs = bfs;
     isamb->method = (ISAMC_M) xmalloc (sizeof(*method));
     memcpy (isamb->method, method, sizeof(*method));
     isamb->no_cat = 4;
+    isamb->log_io = 0;
+    isamb->cache = cache;
 
     isamb->file = xmalloc (sizeof(*isamb->file) * isamb->no_cat);
     for (i = 0; i<isamb->no_cat; i++)
     {
         char fname[DST_BUF_SIZE];
-        isamb->file[i].head.first_block = 1;
-        isamb->file[i].head.last_block = 1;
-        isamb->file[i].head.block_size = b_size;
-        isamb->file[i].head.block_max = b_size - ISAMB_DATA_OFFSET;
-        b_size = b_size * 4;
+        isamb->file[i].cache_entries = 0;
+        isamb->file[i].head_dirty = 0;
+        sprintf (fname, "%s%c", name, i+'A');
+        if (cache)
+            isamb->file[i].bf = bf_open (bfs, fname, ISAMB_CACHE_ENTRY_SIZE,
+                                         writeflag);
+        else
+            isamb->file[i].bf = bf_open (bfs, fname, b_size, writeflag);
+
+        
+        if (!bf_read (isamb->file[i].bf, 0, 0, sizeof(struct ISAMB_head),
+                      &isamb->file[i].head))
+	{
+            isamb->file[i].head.first_block = ISAMB_CACHE_ENTRY_SIZE/b_size+1;
+            isamb->file[i].head.last_block = isamb->file[i].head.first_block;
+            isamb->file[i].head.block_size = b_size;
+            isamb->file[i].head.block_max = b_size - ISAMB_DATA_OFFSET;
+            isamb->file[i].head.free_list = 0;
+	}
+        assert (isamb->file[i].head.block_size >= ISAMB_DATA_OFFSET);
         isamb->file[i].head_dirty = 0;
-        sprintf (fname, "%s-%d", name, i);
-        isamb->file[i].bf =
-            bf_open (bfs, fname, isamb->file[i].head.block_size, writeflag);
-    
-        bf_read (isamb->file[i].bf, 0, 0, sizeof(struct ISAMB_head),
-                 &isamb->file[i].head);
+        assert(isamb->file[i].head.block_size == b_size);
+        b_size = b_size * 4;
     }
     return isamb;
 }
 
+static void flush_blocks (ISAMB b, int cat)
+{
+    while (b->file[cat].cache_entries)
+    {
+        struct ISAMB_cache_entry *ce_this = b->file[cat].cache_entries;
+        b->file[cat].cache_entries = ce_this->next;
+
+        if (ce_this->dirty)
+        {
+            yaz_log (b->log_io, "bf_write: flush_blocks");
+            bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
+        }
+        xfree (ce_this->buf);
+        xfree (ce_this);
+    }
+}
+
+static int get_block (ISAMB b, ISAMC_P pos, char *userbuf, int wr)
+{
+    int cat = pos&3;
+    int off = ((pos/4) & 
+               (ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size - 1))
+        * b->file[cat].head.block_size;
+    int norm = pos / (4*ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size);
+    int no = 0;
+    struct ISAMB_cache_entry **ce, *ce_this = 0, **ce_last = 0;
+
+    if (!b->cache)
+        return 0;
+
+    assert (ISAMB_CACHE_ENTRY_SIZE >= b->file[cat].head.block_size);
+    for (ce = &b->file[cat].cache_entries; *ce; ce = &(*ce)->next, no++)
+    {
+        ce_last = ce;
+        if ((*ce)->pos == norm)
+        {
+            ce_this = *ce;
+            *ce = (*ce)->next;   /* remove from list */
+            
+            ce_this->next = b->file[cat].cache_entries;  /* move to front */
+            b->file[cat].cache_entries = ce_this;
+            
+            if (wr)
+            {
+                memcpy (ce_this->buf + off, userbuf, 
+                        b->file[cat].head.block_size);
+                ce_this->dirty = 1;
+            }
+            else
+                memcpy (userbuf, ce_this->buf + off,
+                        b->file[cat].head.block_size);
+            return 1;
+        }
+    }
+    if (no >= 40)
+    {
+        assert (no == 40);
+        assert (ce_last && *ce_last);
+        ce_this = *ce_last;
+        *ce_last = 0;  /* remove the last entry from list */
+        if (ce_this->dirty)
+        {
+            yaz_log (b->log_io, "bf_write: get_block");
+            bf_write (b->file[cat].bf, ce_this->pos, 0, 0, ce_this->buf);
+        }
+        xfree (ce_this->buf);
+        xfree (ce_this);
+    }
+    ce_this = xmalloc (sizeof(*ce_this));
+    ce_this->next = b->file[cat].cache_entries;
+    b->file[cat].cache_entries = ce_this;
+    ce_this->buf = xmalloc (ISAMB_CACHE_ENTRY_SIZE);
+    ce_this->pos = norm;
+    yaz_log (b->log_io, "bf_read: get_block");
+    if (!bf_read (b->file[cat].bf, norm, 0, 0, ce_this->buf))
+        memset (ce_this->buf, 0, ISAMB_CACHE_ENTRY_SIZE);
+    if (wr)
+    {
+        memcpy (ce_this->buf + off, userbuf, b->file[cat].head.block_size);
+        ce_this->dirty = 1;
+    }
+    else
+    {
+        ce_this->dirty = 0;
+        memcpy (userbuf, ce_this->buf + off, b->file[cat].head.block_size);
+    }
+    return 1;
+}
+
+
 void isamb_close (ISAMB isamb)
 {
     int i;
     for (i = 0; i<isamb->no_cat; i++)
     {
+        flush_blocks (isamb, i);
         if (isamb->file[i].head_dirty)
             bf_write (isamb->file[i].bf, 0, 0,
                       sizeof(struct ISAMB_head), &isamb->file[i].head);
+        
+        bf_close (isamb->file[i].bf);
     }
     xfree (isamb->file);
     xfree (isamb->method);
     xfree (isamb);
 }
 
+
 struct ISAMB_block *open_block (ISAMB b, ISAMC_P pos)
 {
     int cat = pos&3;
@@ -122,12 +267,23 @@ struct ISAMB_block *open_block (ISAMB b, ISAMC_P pos)
     p->pos = pos;
     p->cat = pos & 3;
     p->buf = xmalloc (b->file[cat].head.block_size);
-    bf_read (b->file[cat].bf, pos/4, 0, 0, p->buf);
+
+    if (!get_block (b, pos, p->buf, 0))
+    {
+        yaz_log (b->log_io, "bf_read: open_block");
+        if (!bf_read (b->file[cat].bf, pos/4, 0, 0, p->buf))
+        {
+            yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
+                     (long) pos, (long) pos/4);
+            abort();
+        }
+    }
     p->bytes = p->buf + ISAMB_DATA_OFFSET;
     p->leaf = p->buf[0];
     p->size = p->buf[1] + 256 * p->buf[2] - ISAMB_DATA_OFFSET;
     p->offset = 0;
     p->dirty = 0;
+    p->deleted = 0;
     p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
     return p;
 }
@@ -135,20 +291,41 @@ struct ISAMB_block *open_block (ISAMB b, ISAMC_P pos)
 struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
 {
     struct ISAMB_block *p;
-    int block_no;
-    
+
     p = xmalloc (sizeof(*p));
-    block_no = b->file[cat].head.last_block++;
-    p->cat = cat;
-    p->pos = block_no * 4 + cat;
+    p->buf = xmalloc (b->file[cat].head.block_size);
+
+    if (!b->file[cat].head.free_list)
+    {
+        int block_no;
+        block_no = b->file[cat].head.last_block++;
+        p->pos = block_no * 4 + cat;
+    }
+    else
+    {
+        p->pos = b->file[cat].head.free_list;
+        if (!get_block (b, p->pos, p->buf, 0))
+        {
+            yaz_log (b->log_io, "bf_read: new_block");
+            if (!bf_read (b->file[cat].bf, p->pos/4, 0, 0, p->buf))
+            {
+                yaz_log (LOG_FATAL, "read failure for pos=%ld block=%ld",
+                         (long) p->pos/4, (long) p->pos/4);
+                abort ();
+            }
+        }
+        yaz_log (b->log_freelist, "got block %d from freelist %d:%d", p->pos,
+                 cat, p->pos/4);
+        memcpy (&b->file[cat].head.free_list, p->buf, sizeof(int));
+    }
     p->cat = cat;
     b->file[cat].head_dirty = 1;
-    p->buf = xmalloc (b->file[cat].head.block_size);
     memset (p->buf, 0, b->file[cat].head.block_size);
     p->bytes = p->buf + ISAMB_DATA_OFFSET;
     p->leaf = leaf;
     p->size = 0;
     p->dirty = 1;
+    p->deleted = 0;
     p->offset = 0;
     p->decodeClientData = (*b->method->code_start)(ISAMC_DECODE);
     return p;
@@ -169,13 +346,29 @@ void close_block (ISAMB b, struct ISAMB_block *p)
 {
     if (!p)
         return;
-    if (p->dirty)
+    if (p->deleted)
+    {
+        yaz_log (b->log_freelist, "release block %d from freelist %d:%d",
+                 p->pos, p->cat, p->pos/4);
+        memcpy (p->buf, &b->file[p->cat].head.free_list, sizeof(int));
+        b->file[p->cat].head.free_list = p->pos;
+        if (!get_block (b, p->pos, p->buf, 1))
+        {
+            yaz_log (b->log_io, "bf_write: close_block");
+            bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
+        }
+    }
+    else if (p->dirty)
     {
         int size = p->size + ISAMB_DATA_OFFSET;
         p->buf[0] = p->leaf;
         p->buf[1] = size & 255;
         p->buf[2] = size >> 8;
-        bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
+        if (!get_block (b, p->pos, p->buf, 1))
+        {
+            yaz_log (b->log_io, "bf_write: close_block");
+            bf_write (b->file[p->cat].bf, p->pos/4, 0, 0, p->buf);
+        }
     }
     (*b->method->code_stop)(ISAMC_DECODE, p->decodeClientData);
     xfree (p->buf);
@@ -183,15 +376,16 @@ void close_block (ISAMB b, struct ISAMB_block *p)
 }
 
 int insert_sub (ISAMB b, struct ISAMB_block **p,
-                void *new_item,
+                void *new_item, int *mode,
                 ISAMC_I stream,
                 struct ISAMB_block **sp,
                 void *sub_item, int *sub_size,
                 void *max_item);
 
 int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
+                int *mode,
                 ISAMC_I stream, struct ISAMB_block **sp,
-                void *split_item, int *split_size)
+                void *split_item, int *split_size, void *last_max_item)
 {
     char *startp = p->bytes;
     char *src = startp;
@@ -215,7 +409,8 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
         {
             sub_p1 = open_block (b, pos);
             assert (sub_p1);
-            more = insert_sub (b, &sub_p1, lookahead_item, stream, &sub_p2, 
+            more = insert_sub (b, &sub_p1, lookahead_item, mode,
+                               stream, &sub_p2, 
                                sub_item, &sub_size, src);
             break;
         }
@@ -226,8 +421,8 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
     {
         sub_p1 = open_block (b, pos);
         assert (sub_p1);
-        more = insert_sub (b, &sub_p1, lookahead_item, stream, &sub_p2, 
-                           sub_item, &sub_size, 0);
+        more = insert_sub (b, &sub_p1, lookahead_item, mode, stream, &sub_p2, 
+                           sub_item, &sub_size, last_max_item);
     }
     if (sub_p2)
     {
@@ -294,7 +489,7 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
 
 
 int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
-                 ISAMC_I stream, struct ISAMB_block **sp2,
+                 int *lookahead_mode, ISAMC_I stream, struct ISAMB_block **sp2,
                  void *sub_item, int *sub_size,
                  void *max_item)
 {
@@ -326,17 +521,23 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
             char *dst_item = 0;
             char *dst_0 = dst;
             char *lookahead_next;
-            int lookahead_mode;
             int d = -1;
             
             if (lookahead_item)
                 d = (*b->method->compare_item)(file_item_buf, lookahead_item);
             
-            if (d > 0)  
+            if (d > 0)
+            {
                 dst_item = lookahead_item;
+                assert (*lookahead_mode);
+            }
             else
                 dst_item = file_item_buf;
-            if (!half1 && dst > cut)   
+            if (!*lookahead_mode && d == 0)
+            {
+                p->dirty = 1;
+            }
+            else if (!half1 && dst > cut)
             {
                 char *dst_item_0 = dst_item;
                 half1 = dst; /* candidate for splitting */
@@ -362,15 +563,15 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
                     lookahead_next = lookahead_item;
                     if (!(*stream->read_item)(stream->clientData,
                                               &lookahead_next,
-                                              &lookahead_mode))
+                                              lookahead_mode))
                     {
                         lookahead_item = 0;
                         more = 0;
                     }
-                    if (max_item &&
+                    if (lookahead_item && max_item &&
                         (*b->method->compare_item)(max_item, lookahead_item) <= 0)
                     {
-			yaz_log (LOG_LOG, "max_item 1");
+                        /* max_item 1 */
                         lookahead_item = 0;
                     }
                     
@@ -381,7 +582,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
             {
                 lookahead_next = lookahead_item;
                 if (!(*stream->read_item)(stream->clientData,
-                                          &lookahead_next, &lookahead_mode))
+                                          &lookahead_next, lookahead_mode))
                 {
                     lookahead_item = 0;
                     more = 0;
@@ -403,17 +604,21 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
     maxp = dst_buf + b->file[b->no_cat-1].head.block_max + quater;
     while (lookahead_item)
     {
-        int lookahead_mode;
         char *dst_item = lookahead_item;
         char *dst_0 = dst;
         
         if (max_item &&
             (*b->method->compare_item)(max_item, lookahead_item) <= 0)
         {
- 	    yaz_log (LOG_LOG, "max_item 2");
+            /* max_item 2 */
             break;
         }
-        if (!half1 && dst > cut)   
+        if (!*lookahead_mode)
+        {
+            yaz_log (LOG_WARN, "Inconsistent register (2)");
+            abort();
+        }
+        else if (!half1 && dst > cut)   
         {
             char *dst_item_0 = dst_item;
             half1 = dst; /* candidate for splitting */
@@ -437,7 +642,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
             p->dirty = 1;
         dst_item = lookahead_item;
         if (!(*stream->read_item)(stream->clientData, &dst_item,
-                                  &lookahead_mode))
+                                  lookahead_mode))
         {
             lookahead_item = 0;
             more = 0;
@@ -448,6 +653,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
         new_size > b->file[p->cat].head.block_max)
     {
         /* non-btree block will be removed */
+        p->deleted = 1;
         close_block (b, p);
         /* delete it too!! */
         p = 0; /* make a new one anyway */
@@ -503,16 +709,18 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
 }
 
 int insert_sub (ISAMB b, struct ISAMB_block **p, void *new_item,
+                int *mode,
                 ISAMC_I stream,
                 struct ISAMB_block **sp,
                 void *sub_item, int *sub_size,
                 void *max_item)
 {
     if (!*p || (*p)->leaf)
-        return insert_leaf (b, p, new_item, stream, sp, sub_item, sub_size, 
-                            max_item);
+        return insert_leaf (b, p, new_item, mode, stream, sp, sub_item, 
+                            sub_size, max_item);
     else
-        return insert_int (b, *p, new_item, stream, sp, sub_item, sub_size);
+        return insert_int (b, *p, new_item, mode, stream, sp, sub_item,
+                           sub_size, max_item);
 }
 
 int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
@@ -522,6 +730,17 @@ int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
     int i_mode;
     int more;
 
+    if (b->cache < 0)
+    {
+        int more = 1;
+        while (more)
+        {
+            item_ptr = item_buf;
+            more =
+                (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
+        }
+        return 1;
+    }
     item_ptr = item_buf;
     more = (*stream->read_item)(stream->clientData, &item_ptr, &i_mode);
     while (more)
@@ -532,7 +751,7 @@ int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
         
         if (pos)
             p = open_block (b, pos);
-        more = insert_sub (b, &p, item_buf, stream, &sp,
+        more = insert_sub (b, &p, item_buf, &i_mode, stream, &sp,
                             sub_item, &sub_size, 0);
         if (sp)
         {    /* increase level of tree by one */
@@ -558,21 +777,27 @@ int isamb_merge (ISAMB b, ISAMC_P pos, ISAMC_I stream)
     return pos;
 }
 
-ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
+ISAMB_PP isamb_pp_open_x (ISAMB isamb, ISAMB_P pos, int *level)
 {
     ISAMB_PP pp = xmalloc (sizeof(*pp));
 
     pp->isamb = isamb;
     pp->block = xmalloc (10 * sizeof(*pp->block));
 
+    pp->pos = pos;
     pp->level = 0;
+    pp->total_size = 0;
+    pp->no_blocks = 0;
     while (1)
     {
         struct ISAMB_block *p = open_block (isamb, pos);
         char *src = p->bytes + p->offset;
         pp->block[pp->level] = p;
 
-        if (p->bytes[0]) /* leaf */
+        pp->total_size += p->size;
+        pp->no_blocks++;
+
+        if (p->leaf)
             break;
 
         decode_ptr (&src, &pos);
@@ -580,20 +805,43 @@ ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
         pp->level++;
     }
     pp->block[pp->level+1] = 0;
+    if (level)
+        *level = pp->level;
     return pp;
 }
 
-void isamb_pp_close (ISAMB_PP pp)
+ISAMB_PP isamb_pp_open (ISAMB isamb, ISAMB_P pos)
+{
+    return isamb_pp_open_x (isamb, pos, 0);
+}
+
+void isamb_pp_close_x (ISAMB_PP pp, int *size, int *blocks)
 {
     int i;
     if (!pp)
         return;
+    if (size)
+        *size = pp->total_size;
+    if (blocks)
+        *blocks = pp->no_blocks;
     for (i = 0; i <= pp->level; i++)
         close_block (pp->isamb, pp->block[i]);
     xfree (pp->block);
     xfree (pp);
 }
 
+int isamb_block_info (ISAMB isamb, int cat)
+{
+    if (cat >= 0 && cat < isamb->no_cat)
+        return isamb->file[cat].head.block_size;
+    return -1;
+}
+
+void isamb_pp_close (ISAMB_PP pp)
+{
+    isamb_pp_close_x (pp, 0, 0);
+}
+
 int isamb_pp_read (ISAMB_PP pp, void *buf)
 {
     char *dst = buf;
@@ -613,7 +861,7 @@ int isamb_pp_read (ISAMB_PP pp, void *buf)
             pp->block[pp->level] = 0;
             (pp->level)--;
             p = pp->block[pp->level];
-            assert (p->bytes[0] == 0);  /* must be int */
+            assert (!p->leaf);  /* must be int */
         }
         src = p->bytes + p->offset;
         
@@ -628,6 +876,9 @@ int isamb_pp_read (ISAMB_PP pp, void *buf)
         while (1)
         {
             pp->block[pp->level] = p = open_block (pp->isamb, pos);
+
+            pp->total_size += p->size;
+            pp->no_blocks++;
             
             if (p->leaf) /* leaf */
             {
@@ -640,7 +891,7 @@ int isamb_pp_read (ISAMB_PP pp, void *buf)
         }
     }
     assert (p->offset < p->size);
-    assert (p->bytes[0]);
+    assert (p->leaf);
     src = p->bytes + p->offset;
     (*pp->isamb->method->code_item)(ISAMC_DECODE, p->decodeClientData,
                                     &dst, &src);