X-Git-Url: http://git.indexdata.com/?p=idzebra-moved-to-github.git;a=blobdiff_plain;f=isamb%2Fisamb.c;h=cf96bb515ebc857b1ad53acdaaa9db5210efb20a;hp=7cd0ea936070e9dc030770ad3932f36e0a579c1b;hb=250de4ed23a44f5eb3552db317eef0d0fbe3265c;hpb=161aa7805930f6b91ccea027e4afa4ccce41c379

diff --git a/isamb/isamb.c b/isamb/isamb.c
index 7cd0ea9..cf96bb5 100644
--- a/isamb/isamb.c
+++ b/isamb/isamb.c
@@ -1,8 +1,5 @@
-/* $Id: isamb.c,v 1.89 2006-12-18 23:40:08 adam Exp $
-   Copyright (C) 1995-2006
-   Index Data ApS
-
-This file is part of the Zebra server.
+/* This file is part of the Zebra server.
+   Copyright (C) 2004-2013 Index Data
 
 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
@@ -20,6 +17,9 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
 */
 
+#if HAVE_CONFIG_H
+#include <config.h>
+#endif
 #include <stdlib.h>
 #include <string.h>
 #include <yaz/log.h>
@@ -50,14 +50,17 @@ struct ISAMB_head {
 #define INT_ENCODE 1
 
 /* maximum size of encoded buffer */
-#define DST_ITEM_MAX 256
+#define DST_ITEM_MAX 5000
+
+/* max page size for _any_ isamb use */
+#define ISAMB_MAX_PAGE 32768
 
 #define ISAMB_MAX_LEVEL 10
 /* approx 2*max page + max size of item */
-#define DST_BUF_SIZE (2*4096+300)
+#define DST_BUF_SIZE (2*ISAMB_MAX_PAGE+DST_ITEM_MAX+100)
 
 /* should be maximum block size of multiple thereof */
-#define ISAMB_CACHE_ENTRY_SIZE 4096
+#define ISAMB_CACHE_ENTRY_SIZE ISAMB_MAX_PAGE
 
 /* CAT_MAX: _must_ be power of 2 */
 #define CAT_MAX 4
@@ -98,7 +101,7 @@ struct ISAMB_s {
     int log_io;        /* log level for bf_read/bf_write calls */
     int log_freelist;  /* log level for freelist handling */
     zint skipped_numbers; /* on a leaf node */
-    zint returned_numbers; 
+    zint returned_numbers;
     zint skipped_nodes[ISAMB_MAX_LEVEL]; /* [0]=skipped leaves, 1 = higher etc */
     zint accessed_nodes[ISAMB_MAX_LEVEL]; /* nodes we did not skip */
     zint number_of_int_splits;
@@ -133,7 +136,7 @@ struct ISAMB_PP_s {
     zint total_size;
     zint no_blocks;
     zint skipped_numbers; /* on a leaf node */
-    zint returned_numbers; 
+    zint returned_numbers;
     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;
@@ -149,8 +152,8 @@ static void encode_ptr(char **dst, zint pos)
 
     while (pos > 127)
     {
-         *bp++ = (unsigned char) (128 | (pos & 127));
-         pos = pos >> 7;
+        *bp++ = (unsigned char) (128 | (pos & 127));
+        pos = pos >> 7;
     }
     *bp++ = (unsigned char) pos;
     *dst = (char *) bp;
@@ -182,8 +185,8 @@ static void decode_ptr(const char **src, zint *pos)
 #else
 static void decode_ptr(const char **src, zint *pos)
 {
-     memcpy(pos, *src, sizeof(*pos));
-     (*src) += sizeof(*pos);
+    memcpy(pos, *src, sizeof(*pos));
+    (*src) += sizeof(*pos);
 }
 #endif
 
@@ -255,7 +258,7 @@ ISAMB isamb_open2(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
         sprintf(fname, "%s%c", name, i+'A');
         if (cache)
             isamb->file[i].bf = bf_open(bfs, fname, ISAMB_CACHE_ENTRY_SIZE,
-                                         writeflag);
+                                        writeflag);
         else
             isamb->file[i].bf = bf_open(bfs, fname, sizes[i], writeflag);
 
@@ -291,17 +294,20 @@ ISAMB isamb_open2(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
 	    if (memcmp(hbuf, "isamb", 5))
 	    {
 		yaz_log(YLOG_WARN, "bad isamb header for file %s", fname);
+                isamb_close(isamb);
 		return 0;
 	    }
 	    if (sscanf(hbuf+5, "%d %d %d", &major, &minor, &len) != 3)
 	    {
 		yaz_log(YLOG_WARN, "bad isamb header for file %s", fname);
+                isamb_close(isamb);
 		return 0;
 	    }
 	    if (major != ISAMB_MAJOR_VERSION)
 	    {
 		yaz_log(YLOG_WARN, "bad major version for file %s %d, must be %d",
-		     fname, major, ISAMB_MAJOR_VERSION);
+                        fname, major, ISAMB_MAJOR_VERSION);
+                isamb_close(isamb);
 		return 0;
 	    }
 	    for (left = len - sizes[i]; left > 0; left = left - sizes[i])
@@ -309,9 +315,10 @@ ISAMB isamb_open2(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
 		pos++;
 		if (!bf_read(isamb->file[i].bf, pos, 0, 0, hbuf + pos*sizes[i]))
 		{
-		    yaz_log(YLOG_WARN, "truncated isamb header for " 
-			 "file=%s len=%d pos=%d",
-			 fname, len, pos);
+		    yaz_log(YLOG_WARN, "truncated isamb header for "
+                            "file=%s len=%d pos=%d",
+                            fname, len, pos);
+                    isamb_close(isamb);
 		    return 0;
 		}
 	    }
@@ -326,8 +333,12 @@ ISAMB isamb_open2(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
             if (isamb->minor_version >= ISAMB_MINOR_VERSION_WITH_ROOT)
                 decode_ptr(&src, &isamb->root_ptr);
 	}
-        assert (isamb->file[i].head.block_size >= isamb->file[i].head.block_offset);
-        isamb->file[i].head_dirty = 0;
+        assert(isamb->file[i].head.block_size >= isamb->file[i].head.block_offset);
+        /* must rewrite the header if root ptr is in use (bug #1017) */
+        if (use_root_ptr && writeflag)
+            isamb->file[i].head_dirty = 1;
+        else
+            isamb->file[i].head_dirty = 0;
         assert(isamb->file[i].head.block_size == sizes[i]);
     }
 #if ISAMB_DEBUG
@@ -341,7 +352,7 @@ ISAMB isamb_open(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
 {
     int sizes[CAT_NO];
     int i, b_size = ISAMB_MIN_SIZE;
-    
+
     for (i = 0; i<CAT_NO; i++)
     {
         sizes[i] = b_size;
@@ -351,7 +362,7 @@ ISAMB isamb_open(BFiles bfs, const char *name, int writeflag, ISAMC_M *method,
                        CAT_NO, sizes, 0);
 }
 
-static void flush_blocks (ISAMB b, int cat)
+static void flush_blocks(ISAMB b, int cat)
 {
     while (b->file[cat].cache_entries)
     {
@@ -368,12 +379,12 @@ static void flush_blocks (ISAMB b, int cat)
     }
 }
 
-static int cache_block (ISAMB b, ISAM_P pos, unsigned char *userbuf, int wr)
+static int cache_block(ISAMB b, ISAM_P pos, unsigned char *userbuf, int wr)
 {
     int cat = (int) (pos&CAT_MASK);
-    int off = (int) (((pos/CAT_MAX) & 
-               (ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size - 1))
-        * b->file[cat].head.block_size);
+    int off = (int) (((pos/CAT_MAX) &
+                      (ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size - 1))
+                     * b->file[cat].head.block_size);
     zint norm = pos / (CAT_MASK*ISAMB_CACHE_ENTRY_SIZE / b->file[cat].head.block_size);
     int no = 0;
     struct ISAMB_cache_entry **ce, *ce_this = 0, **ce_last = 0;
@@ -381,7 +392,7 @@ static int cache_block (ISAMB b, ISAM_P pos, unsigned char *userbuf, int wr)
     if (!b->cache)
         return 0;
 
-    assert (ISAMB_CACHE_ENTRY_SIZE >= b->file[cat].head.block_size);
+    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;
@@ -389,25 +400,25 @@ static int cache_block (ISAMB b, ISAM_P pos, unsigned char *userbuf, int wr)
         {
             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);
+                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);
+                memcpy(userbuf, ce_this->buf + off,
+                       b->file[cat].head.block_size);
             return 1;
         }
     }
     if (no >= b->cache_size)
     {
-        assert (ce_last && *ce_last);
+        assert(ce_last && *ce_last);
         ce_this = *ce_last;
         *ce_last = 0;  /* remove the last entry from list */
         if (ce_this->dirty)
@@ -425,34 +436,35 @@ static int cache_block (ISAMB b, ISAM_P pos, unsigned char *userbuf, int wr)
     ce_this->pos = norm;
     yaz_log(b->log_io, "bf_read: cache_block");
     if (!bf_read(b->file[cat].bf, norm, 0, 0, ce_this->buf))
-        memset (ce_this->buf, 0, ISAMB_CACHE_ENTRY_SIZE);
+        memset(ce_this->buf, 0, ISAMB_CACHE_ENTRY_SIZE);
     if (wr)
     {
-        memcpy (ce_this->buf + off, userbuf, b->file[cat].head.block_size);
+        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);
+        memcpy(userbuf, ce_this->buf + off, b->file[cat].head.block_size);
     }
     return 1;
 }
 
 
-void isamb_close (ISAMB isamb)
+void isamb_close(ISAMB isamb)
 {
     int i;
     for (i = 0; isamb->accessed_nodes[i]; i++)
         yaz_log(YLOG_DEBUG, "isamb_close  level leaf-%d: "ZINT_FORMAT" read, "
-			ZINT_FORMAT" skipped",
-             i, isamb->accessed_nodes[i], isamb->skipped_nodes[i]);
+                ZINT_FORMAT" skipped",
+                i, isamb->accessed_nodes[i], isamb->skipped_nodes[i]);
     yaz_log(YLOG_DEBUG, "isamb_close returned "ZINT_FORMAT" values, "
-		   "skipped "ZINT_FORMAT,
-         isamb->skipped_numbers, isamb->returned_numbers);
+            "skipped "ZINT_FORMAT,
+            isamb->skipped_numbers, isamb->returned_numbers);
+
     for (i = 0; i<isamb->no_cat; i++)
     {
-        flush_blocks (isamb, i);
+        flush_blocks(isamb, i);
         if (isamb->file[i].head_dirty)
 	{
 	    char hbuf[DST_BUF_SIZE];
@@ -501,9 +513,9 @@ void isamb_close (ISAMB isamb)
    0: leader byte, != 0 leaf, == 0, non-leaf
    1-2: used size of block
    3-7*: number of items and all children
-   
+
    * Reserve 5 bytes for large block sizes. 1 for small ones .. Number
-   of items. We can thus have at most 2^40 nodes. 
+   of items. We can thus have at most 2^40 nodes.
 */
 static struct ISAMB_block *open_block(ISAMB b, ISAM_P pos)
 {
@@ -525,7 +537,7 @@ static struct ISAMB_block *open_block(ISAMB b, ISAM_P pos)
         if (bf_read(b->file[cat].bf, pos/CAT_MAX, 0, 0, p->buf) != 1)
         {
             yaz_log(YLOG_FATAL, "isamb: read fail for pos=%ld block=%ld",
-                     (long) pos, (long) pos/CAT_MAX);
+                    (long) pos, (long) pos/CAT_MAX);
             zebra_exit("isamb:open_block");
         }
     }
@@ -535,9 +547,9 @@ static struct ISAMB_block *open_block(ISAMB b, ISAM_P pos)
     if (p->size < 0)
     {
         yaz_log(YLOG_FATAL, "Bad block size %d in pos=" ZINT_FORMAT "\n",
-		 p->size, pos);
+                p->size, pos);
     }
-    assert (p->size >= 0);
+    assert(p->size >= 0);
     src = (char*) p->buf + 3;
     decode_ptr(&src, &p->no_items);
 
@@ -548,7 +560,7 @@ static struct ISAMB_block *open_block(ISAMB b, ISAM_P pos)
     return p;
 }
 
-struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
+struct ISAMB_block *new_block(ISAMB b, int leaf, int cat)
 {
     struct ISAMB_block *p;
 
@@ -560,28 +572,34 @@ struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
         zint block_no;
         block_no = b->file[cat].head.last_block++;
         p->pos = block_no * CAT_MAX + cat;
+        if (b->log_freelist)
+            yaz_log(b->log_freelist, "got block "
+                    ZINT_FORMAT " from last %d:" ZINT_FORMAT, p->pos,
+                    cat, p->pos/CAT_MAX);
     }
     else
     {
         p->pos = b->file[cat].head.free_list;
         assert((p->pos & CAT_MASK) == cat);
-        if (!cache_block (b, p->pos, p->buf, 0))
+        if (!cache_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/CAT_MAX, 0, 0, p->buf))
             {
                 yaz_log(YLOG_FATAL, "isamb: read fail for pos=%ld block=%ld",
-                         (long) p->pos/CAT_MAX, (long) p->pos/CAT_MAX);
+                        (long) p->pos/CAT_MAX, (long) p->pos/CAT_MAX);
                 zebra_exit("isamb:new_block");
             }
         }
-        yaz_log(b->log_freelist, "got block " ZINT_FORMAT " from freelist %d:" ZINT_FORMAT, p->pos,
-                 cat, p->pos/CAT_MAX);
-        memcpy (&b->file[cat].head.free_list, p->buf, sizeof(zint));
+        if (b->log_freelist)
+            yaz_log(b->log_freelist, "got block "
+                    ZINT_FORMAT " from freelist %d:" ZINT_FORMAT, p->pos,
+                    cat, p->pos/CAT_MAX);
+        memcpy(&b->file[cat].head.free_list, p->buf, sizeof(zint));
     }
     p->cat = cat;
     b->file[cat].head_dirty = 1;
-    memset (p->buf, 0, b->file[cat].head.block_size);
+    memset(p->buf, 0, b->file[cat].head.block_size);
     p->bytes = (char*)p->buf + b->file[cat].head.block_offset;
     p->leaf = leaf;
     p->size = 0;
@@ -593,18 +611,18 @@ struct ISAMB_block *new_block (ISAMB b, int leaf, int cat)
     return p;
 }
 
-struct ISAMB_block *new_leaf (ISAMB b, int cat)
+struct ISAMB_block *new_leaf(ISAMB b, int cat)
 {
-    return new_block (b, 1, cat);
+    return new_block(b, 1, cat);
 }
 
 
-struct ISAMB_block *new_int (ISAMB b, int cat)
+struct ISAMB_block *new_int(ISAMB b, int cat)
 {
-    return new_block (b, 0, cat);
+    return new_block(b, 0, cat);
 }
 
-static void check_block (ISAMB b, struct ISAMB_block *p)
+static void check_block(ISAMB b, struct ISAMB_block *p)
 {
     assert(b); /* mostly to make the compiler shut up about unused b */
     if (p->leaf)
@@ -619,9 +637,9 @@ static void check_block (ISAMB b, struct ISAMB_block *p)
         char *endp = p->bytes + p->size;
         ISAM_P pos;
 	void *c1 = (*b->method->codec.start)();
-            
+
         decode_ptr(&src, &pos);
-        assert ((pos&CAT_MASK) == p->cat);
+        assert((pos&CAT_MASK) == p->cat);
         while (src != endp)
         {
 #if INT_ENCODE
@@ -632,13 +650,13 @@ static void check_block (ISAMB b, struct ISAMB_block *p)
 #else
             zint item_len;
             decode_item_len(&src, &item_len);
-            assert (item_len > 0 && item_len < 80);
+            assert(item_len > 0 && item_len < 128);
             src += item_len;
 #endif
             decode_ptr(&src, &pos);
 	    if ((pos&CAT_MASK) != p->cat)
 	    {
-		assert ((pos&CAT_MASK) == p->cat);
+		assert((pos&CAT_MASK) == p->cat);
 	    }
         }
 	(*b->method->codec.stop)(c1);
@@ -652,10 +670,11 @@ void close_block(ISAMB b, struct ISAMB_block *p)
     if (p->deleted)
     {
         yaz_log(b->log_freelist, "release block " ZINT_FORMAT " from freelist %d:" ZINT_FORMAT,
-                 p->pos, p->cat, p->pos/CAT_MAX);
-        memcpy (p->buf, &b->file[p->cat].head.free_list, sizeof(zint));
+                p->pos, p->cat, p->pos/CAT_MAX);
+        memcpy(p->buf, &b->file[p->cat].head.free_list, sizeof(zint));
         b->file[p->cat].head.free_list = p->pos;
-        if (!cache_block (b, p->pos, p->buf, 1))
+        b->file[p->cat].head_dirty = 1;
+        if (!cache_block(b, p->pos, p->buf, 1))
         {
             yaz_log(b->log_io, "bf_write: close_block (deleted)");
             bf_write(b->file[p->cat].bf, p->pos/CAT_MAX, 0, 0, p->buf);
@@ -666,8 +685,8 @@ void close_block(ISAMB b, struct ISAMB_block *p)
 	int offset = b->file[p->cat].head.block_offset;
         int size = p->size + offset;
 	char *dst =  (char*)p->buf + 3;
-        assert (p->size >= 0);
-	
+        assert(p->size >= 0);
+
 	/* memset becuase encode_ptr usually does not write all bytes */
 	memset(p->buf, 0, b->file[p->cat].head.block_offset);
         p->buf[0] = p->leaf;
@@ -675,7 +694,7 @@ void close_block(ISAMB b, struct ISAMB_block *p)
         p->buf[2] = size >> 8;
 	encode_ptr(&dst, p->no_items);
         check_block(b, p);
-        if (!cache_block (b, p->pos, p->buf, 1))
+        if (!cache_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/CAT_MAX, 0, 0, p->buf);
@@ -686,17 +705,17 @@ void close_block(ISAMB b, struct ISAMB_block *p)
     xfree(p);
 }
 
-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,
-                const 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, const void *last_max_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,
+               const 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, const void *last_max_item)
 {
     char *startp = p->bytes;
     const char *src = startp;
@@ -726,11 +745,11 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
         if (d > 0)
         {
             sub_p1 = open_block(b, pos);
-            assert (sub_p1);
+            assert(sub_p1);
 	    diff_terms -= sub_p1->no_items;
-            more = insert_sub (b, &sub_p1, lookahead_item, mode,
-                               stream, &sub_p2, 
-                               sub_item, &sub_size, file_item_buf);
+            more = insert_sub(b, &sub_p1, lookahead_item, mode,
+                              stream, &sub_p2,
+                              sub_item, &sub_size, file_item_buf);
 	    diff_terms += sub_p1->no_items;
             src = src0;
             break;
@@ -742,11 +761,11 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
         if (d > 0)
         {
             sub_p1 = open_block(b, pos);
-            assert (sub_p1);
+            assert(sub_p1);
 	    diff_terms -= sub_p1->no_items;
-            more = insert_sub (b, &sub_p1, lookahead_item, mode,
-                               stream, &sub_p2, 
-                               sub_item, &sub_size, src);
+            more = insert_sub(b, &sub_p1, lookahead_item, mode,
+                              stream, &sub_p2,
+                              sub_item, &sub_size, src);
 	    diff_terms += sub_p1->no_items;
             src = src0;
             break;
@@ -759,10 +778,10 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
     {
 	/* we reached the end. So lookahead > last item */
         sub_p1 = open_block(b, pos);
-        assert (sub_p1);
+        assert(sub_p1);
 	diff_terms -= sub_p1->no_items;
-        more = insert_sub (b, &sub_p1, lookahead_item, mode, stream, &sub_p2, 
-                           sub_item, &sub_size, last_max_item);
+        more = insert_sub(b, &sub_p1, lookahead_item, mode, stream, &sub_p2,
+                          sub_item, &sub_size, last_max_item);
 	diff_terms += sub_p1->no_items;
     }
     if (sub_p2)
@@ -780,18 +799,18 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
 #if INT_ENCODE
 	const char *sub_item_ptr = sub_item;
 #endif
-        assert (sub_size < 80 && sub_size > 1);
+        assert(sub_size < DST_ITEM_MAX && sub_size > 1);
+
+        memcpy(dst, startp, src - startp);
 
-        memcpy (dst, startp, src - startp);
-                
         dst += src - startp;
 
 #if INT_ENCODE
 	(*b->method->codec.reset)(c1);
         (*b->method->codec.encode)(c1, &dst, &sub_item_ptr);
 #else
-        encode_item_len (&dst, sub_size);      /* sub length and item */
-        memcpy (dst, sub_item, sub_size);
+        encode_item_len(&dst, sub_size);      /* sub length and item */
+        memcpy(dst, sub_item, sub_size);
         dst += sub_size;
 #endif
 
@@ -799,16 +818,16 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
 
         if (endp - src)                   /* remaining data */
         {
-            memcpy (dst, src, endp - src);
+            memcpy(dst, src, endp - src);
             dst += endp - src;
         }
         p->size = dst - dst_buf;
-        assert (p->size >= 0);
+        assert(p->size >= 0);
 
         if (p->size <= b->file[p->cat].head.block_max)
         {
 	    /* it fits OK in this block */
-            memcpy (startp, dst_buf, dst - dst_buf);
+            memcpy(startp, dst_buf, dst - dst_buf);
 
 	    close_block(b, sub_p2);
         }
@@ -827,7 +846,7 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
             const char *half;
             src = dst_buf;
             endp = dst;
-            
+
             b->number_of_int_splits++;
 
 	    p->dirty = 1;
@@ -867,7 +886,7 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
             }
 	    /*  p is first half */
             p_new_size = src - dst_buf;
-            memcpy (p->bytes, dst_buf, p_new_size);
+            memcpy(p->bytes, dst_buf, p_new_size);
 
 #if INT_ENCODE
 	    file_item = file_item_buf;
@@ -878,13 +897,13 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
 #else
 	    decode_item_len(&src, &split_size_tmp);
 	    *split_size = (int) split_size_tmp;
-            memcpy (split_item, src, *split_size);
+            memcpy(split_item, src, *split_size);
             src += *split_size;
 #endif
 	    /*  *sp is second half */
-            *sp = new_int (b, p->cat);
+            *sp = new_int(b, p->cat);
             (*sp)->size = endp - src;
-            memcpy ((*sp)->bytes, src, (*sp)->size);
+            memcpy((*sp)->bytes, src, (*sp)->size);
 
             p->size = p_new_size;
 
@@ -899,11 +918,11 @@ int insert_int (ISAMB b, struct ISAMB_block *p, void *lookahead_item,
     return more;
 }
 
-int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
-                 int *lookahead_mode, ISAMC_I *stream,
-		 struct ISAMB_block **sp2,
-                 void *sub_item, int *sub_size,
-                 const void *max_item)
+int insert_leaf(ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
+                int *lookahead_mode, ISAMC_I *stream,
+                struct ISAMB_block **sp2,
+                void *sub_item, int *sub_size,
+                const void *max_item)
 {
     struct ISAMB_block *p = *sp1;
     char *endp = 0;
@@ -929,7 +948,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
     {
         char file_item_buf[DST_ITEM_MAX];
         char *file_item = file_item_buf;
-            
+
         src = p->bytes;
         endp = p->bytes + p->size;
         (*b->method->codec.decode)(c1, &file_item, &src);
@@ -939,12 +958,12 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
             char *lookahead_next;
 	    char *dst_0 = dst;
             int d = -1;
-            
+
             if (lookahead_item)
                 d = (*b->method->compare_item)(file_item_buf, lookahead_item);
-            
+
 	    /* d now holds comparison between existing file item and
-	       lookahead item 
+	       lookahead item
 	       d = 0: equal
                d > 0: lookahead before file
 	       d < 0: lookahead after file
@@ -960,14 +979,22 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
                     assert(*lookahead_mode);
                 }
             }
+            else if (d == 0 && *lookahead_mode == 2)
+            {
+                /* For mode == 2, we insert the new key anyway - even
+                   though the comparison is 0. */
+                dst_item = lookahead_item;
+                p->dirty = 1;
+            }
             else
                 dst_item = file_item_buf;
 
-            if (!*lookahead_mode && d == 0)
+            if (d == 0 && !*lookahead_mode)
             {
-		/* it's a deletion and they match so there is nothing to be
-		   inserted anyway .. But mark the thing bad (file item
-		   was part of input.. The item will not be part of output */
+                /* it's a deletion and they match so there is nothing
+                   to be inserted anyway .. But mark the thing dirty
+                   (file item was part of input.. The item will not be
+                   part of output */
                 p->dirty = 1;
             }
             else if (!half1 && dst > mid_cut)
@@ -978,11 +1005,11 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
 
 		/* encode the resulting item */
                 (*b->method->codec.encode)(c2, &dst, &dst_item);
-                
+
                 cut_item_size = dst_item - dst_item_0;
 		assert(cut_item_size > 0);
-                memcpy (cut_item_buf, dst_item_0, cut_item_size);
-                
+                memcpy(cut_item_buf, dst_item_0, cut_item_size);
+
                 half2 = dst;
 		no_items_1 = no_items;
 		no_items++;
@@ -995,7 +1022,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
 	    }
 
 	    /* now move "pointers" .. result has been encoded .. */
-            if (d > 0)  
+            if (d > 0)
             {
 		/* we must move the lookahead pointer */
 
@@ -1022,7 +1049,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
 			   leaf. Mark it as "gone" */
                         lookahead_item = 0;
                     }
-                    
+
                     p->dirty = 1;
                 }
             }
@@ -1063,7 +1090,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
         char *dst_item;
 	const char *src = lookahead_item;
         char *dst_0 = dst;
-        
+
 	/* if we have a lookahead item, we stop if we exceed the value of it */
         if (max_item &&
             (*b->method->compare_item)(max_item, lookahead_item) <= 0)
@@ -1081,13 +1108,13 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
         {
             const char *src_0 = src;
             half1 = dst; /* candidate for splitting */
-            
+
             (*b->method->codec.encode)(c2, &dst, &src);
-            
+
             cut_item_size = src - src_0;
 	    assert(cut_item_size > 0);
-            memcpy (cut_item_buf, src_0, cut_item_size);
-            
+            memcpy(cut_item_buf, src_0, cut_item_size);
+
 	    no_items_1 = no_items;
             half2 = dst;
         }
@@ -1111,7 +1138,7 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
         }
     }
     new_size = dst - dst_buf;
-    if (p && p->cat != b->no_cat-1 && 
+    if (p && p->cat != b->no_cat-1 &&
         new_size > b->file[p->cat].head.block_max)
     {
         /* non-btree block will be removed */
@@ -1128,26 +1155,26 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
                 break;
         if (i == b->no_cat)
             i = b->no_cat - 1;
-        p = new_leaf (b, i);
+        p = new_leaf(b, i);
     }
     if (new_size > b->file[p->cat].head.block_max)
     {
         char *first_dst;
         const char *cut_item = cut_item_buf;
 
-        assert (half1);
-        assert (half2);
+        assert(half1);
+        assert(half2);
 
 	assert(cut_item_size > 0);
-	
+
 	/* first half */
         p->size = half1 - dst_buf;
 	assert(p->size <=  b->file[p->cat].head.block_max);
-        memcpy (p->bytes, dst_buf, half1 - dst_buf);
+        memcpy(p->bytes, dst_buf, half1 - dst_buf);
 	p->no_items = no_items_1;
 
         /* second half */
-        *sp2 = new_leaf (b, p->cat);
+        *sp2 = new_leaf(b, p->cat);
 
         (*b->method->codec.reset)(c2);
 
@@ -1157,19 +1184,19 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
 
         (*b->method->codec.encode)(c2, &first_dst, &cut_item);
 
-        memcpy (first_dst, half2, dst - half2);
+        memcpy(first_dst, half2, dst - half2);
 
         (*sp2)->size = (first_dst - (*sp2)->bytes) + (dst - half2);
 	assert((*sp2)->size <=  b->file[p->cat].head.block_max);
 	(*sp2)->no_items = no_items - no_items_1;
         (*sp2)->dirty = 1;
         p->dirty = 1;
-        memcpy (sub_item, cut_item_buf, cut_item_size);
+        memcpy(sub_item, cut_item_buf, cut_item_size);
         *sub_size = cut_item_size;
     }
     else
     {
-        memcpy (p->bytes, dst_buf, dst - dst_buf);
+        memcpy(p->bytes, dst_buf, dst - dst_buf);
         p->size = new_size;
 	p->no_items = no_items;
     }
@@ -1179,22 +1206,22 @@ int insert_leaf (ISAMB b, struct ISAMB_block **sp1, void *lookahead_item,
     return more;
 }
 
-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,
-                const void *max_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,
+               const void *max_item)
 {
     if (!*p || (*p)->leaf)
-        return insert_leaf (b, p, new_item, mode, stream, sp, sub_item, 
-                            sub_size, max_item);
-    else
-        return insert_int (b, *p, new_item, mode, stream, sp, sub_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, mode, stream, sp, sub_item,
+                          sub_size, max_item);
 }
 
-int isamb_unlink (ISAMB b, ISAM_P pos)
+int isamb_unlink(ISAMB b, ISAM_P pos)
 {
     struct ISAMB_block *p1;
 
@@ -1211,7 +1238,7 @@ int isamb_unlink (ISAMB b, ISAM_P pos)
 #endif
 	decode_ptr(&src, &sub_p);
 	isamb_unlink(b, sub_p);
-	
+
 	while (src != p1->bytes + p1->size)
 	{
 #if INT_ENCODE
@@ -1262,14 +1289,14 @@ void isamb_merge(ISAMB b, ISAM_P *pos, ISAMC_I *stream)
         struct ISAMB_block *p = 0, *sp = 0;
         char sub_item[DST_ITEM_MAX];
         int sub_size;
-        
+
         if (*pos)
             p = open_block(b, *pos);
-        more = insert_sub (b, &p, item_buf, &i_mode, stream, &sp,
-			   sub_item, &sub_size, 0);
+        more = insert_sub(b, &p, item_buf, &i_mode, stream, &sp,
+                          sub_item, &sub_size, 0);
         if (sp)
         {    /* increase level of tree by one */
-            struct ISAMB_block *p2 = new_int (b, p->cat);
+            struct ISAMB_block *p2 = new_int(b, p->cat);
             char *dst = p2->bytes + p2->size;
 #if INT_ENCODE
 	    void *c1 = (*b->method->codec.start)();
@@ -1277,17 +1304,17 @@ void isamb_merge(ISAMB b, ISAM_P *pos, ISAMC_I *stream)
 #endif
 
             encode_ptr(&dst, p->pos);
-	    assert (sub_size < 80 && sub_size > 1);
+	    assert(sub_size < DST_ITEM_MAX && sub_size > 1);
 #if INT_ENCODE
 	    (*b->method->codec.reset)(c1);
 	    (*b->method->codec.encode)(c1, &dst, &sub_item_ptr);
 #else
-            encode_item_len (&dst, sub_size);
-            memcpy (dst, sub_item, sub_size);
+            encode_item_len(&dst, sub_size);
+            memcpy(dst, sub_item, sub_size);
             dst += sub_size;
 #endif
             encode_ptr(&dst, sp->pos);
-            
+
             p2->size = dst - p2->bytes;
 	    p2->no_items = p->no_items + sp->no_items;
             *pos = p2->pos;  /* return new super page */
@@ -1347,7 +1374,7 @@ ISAMB_PP isamb_pp_open_x(ISAMB isamb, ISAM_P pos, int *level, int scope)
         decode_ptr(&src, &pos);
         p->offset = src - p->bytes;
         pp->level++;
-        pp->accessed_nodes[pp->level]++; 
+        pp->accessed_nodes[pp->level]++;
     }
     pp->block[pp->level+1] = 0;
     pp->maxlevel = pp->level;
@@ -1356,7 +1383,7 @@ ISAMB_PP isamb_pp_open_x(ISAMB isamb, ISAM_P pos, int *level, int scope)
     return pp;
 }
 
-ISAMB_PP isamb_pp_open (ISAMB isamb, ISAM_P pos, int scope)
+ISAMB_PP isamb_pp_open(ISAMB isamb, ISAM_P pos, int scope)
 {
     return isamb_pp_open_x(isamb, pos, 0, scope);
 }
@@ -1366,14 +1393,14 @@ void isamb_pp_close_x(ISAMB_PP pp, zint *size, zint *blocks)
     int i;
     if (!pp)
         return;
-    yaz_log(YLOG_DEBUG, "isamb_pp_close lev=%d returned "ZINT_FORMAT" values, " 
-		    "skipped "ZINT_FORMAT,
-        pp->maxlevel, pp->skipped_numbers, pp->returned_numbers);
+    yaz_log(YLOG_DEBUG, "isamb_pp_close lev=%d returned "ZINT_FORMAT" values, "
+            "skipped "ZINT_FORMAT,
+            pp->maxlevel, pp->skipped_numbers, pp->returned_numbers);
     for (i = pp->maxlevel; i>=0; i--)
         if (pp->skipped_nodes[i] || pp->accessed_nodes[i])
             yaz_log(YLOG_DEBUG, "isamb_pp_close  level leaf-%d: "
-			    ZINT_FORMAT" read, "ZINT_FORMAT" skipped", i,
-                 pp->accessed_nodes[i], pp->skipped_nodes[i]);
+                    ZINT_FORMAT" read, "ZINT_FORMAT" skipped", i,
+                    pp->accessed_nodes[i], pp->skipped_nodes[i]);
     pp->isamb->skipped_numbers += pp->skipped_numbers;
     pp->isamb->returned_numbers += pp->returned_numbers;
     for (i = pp->maxlevel; i>=0; i--)
@@ -1391,21 +1418,21 @@ void isamb_pp_close_x(ISAMB_PP pp, zint *size, zint *blocks)
     xfree(pp);
 }
 
-int isamb_block_info (ISAMB isamb, int cat)
+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)
+void isamb_pp_close(ISAMB_PP pp)
 {
     isamb_pp_close_x(pp, 0, 0);
 }
 
 /* simple recursive dumper .. */
-static void isamb_dump_r (ISAMB b, ISAM_P pos, void (*pr)(const char *str),
-			  int level)
+static void isamb_dump_r(ISAMB b, ISAM_P pos, void (*pr)(const char *str),
+                         int level)
 {
     char buf[1024];
     char prefix_str[1024];
@@ -1439,7 +1466,7 @@ static void isamb_dump_r (ISAMB b, ISAM_P pos, void (*pr)(const char *str),
 	    p->offset = src - (char*) p->bytes;
 
 	    isamb_dump_r(b, sub, pr, level+1);
-	    
+
 	    while (p->offset < p->size)
 	    {
 #if INT_ENCODE
@@ -1456,11 +1483,11 @@ static void isamb_dump_r (ISAMB b, ISAM_P pos, void (*pr)(const char *str),
 		src += item_len;
 #endif
 		decode_ptr(&src, &sub);
-		
+
 		p->offset = src - (char*) p->bytes;
-		
+
 		isamb_dump_r(b, sub, pr, level+1);
-	    }		
+	    }
 	}
 	close_block(b, p);
     }
@@ -1477,428 +1504,23 @@ int isamb_pp_read(ISAMB_PP pp, void *buf)
 }
 
 
-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 */
-  /* useful in backing off quickly, and in avoiding tail descends */
-  /* call with pp->level to begin with */
-    struct ISAMB_block *p;
-    int cmp;
-    const char *src;
-    ISAMB b = pp->isamb;
-
-    assert(level >= 0);
-    if (level == 0)
-    {
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_on_right returning true for root");
-#endif
-        return 1; /* we can never skip the root node */
-    }
-    level--;
-    p = pp->block[level];
-    assert(p->offset <= p->size);
-    if (p->offset < p->size)
-    {
-#if INT_ENCODE
-	char file_item_buf[DST_ITEM_MAX];
-	char *file_item = file_item_buf;
-	void *c1 = (*b->method->codec.start)();
-        assert(p->offset > 0); 
-        src = p->bytes + p->offset;
-        (*b->method->codec.decode)(c1, &file_item, &src);
-	(*b->method->codec.stop)(c1);
-	cmp = (*b->method->compare_item)(untilbuf, file_item_buf);
-#else
-	zint item_len;
-        assert(p->offset > 0); 
-        src = p->bytes + p->offset;
-        decode_item_len(&src, &item_len);
-#if ISAMB_DEBUG
-        (*b->method->codec.log_item)(YLOG_DEBUG, untilbuf, "on_leaf: until");
-        (*b->method->codec.log_item)(YLOG_DEBUG, src, "on_leaf: value");
-#endif
-        cmp = (*b->method->compare_item)(untilbuf, src);
-#endif
-        if (cmp < pp->scope)
-	{  /* cmp<2 */
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_on_right returning true "
-                            "cmp=%d lev=%d ofs=%d", cmp, level, p->offset);
-#endif
-            return 1; 
-        }
-        else
-	{
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_on_right returning false "
-                            "cmp=%d lev=%d ofs=%d", cmp, level, p->offset);
-#endif
-            return 0; 
-        }
-    }
-    else {
-#if ISAMB_DEBUG
-        yaz_log(YLOG_DEBUG, "isamb_pp_on_right at tail, looking higher "
-                        "lev=%d", level);
-#endif
-        return isamb_pp_on_right_node(pp, level, untilbuf);
-    }
-} /* isamb_pp_on_right_node */
-
-static int isamb_pp_read_on_leaf(ISAMB_PP pp, void *buf)
-{ 
-    /* reads the next item on the current leaf, returns 0 if end of leaf*/
-    struct ISAMB_block *p = pp->block[pp->level];
-    char *dst;
-    const char *src;
-    assert(pp);
-    assert(buf);
-    if (p->offset == p->size)
-    {
-#if ISAMB_DEBUG
-        yaz_log(YLOG_DEBUG, "isamb_pp_read_on_leaf returning 0 on "
-		"node %d", p->pos);
-#endif
-        return 0; /* at end of leaf */
-    }
-    src = p->bytes + 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)(YLOG_DEBUG, buf,
-					 "read_on_leaf returning 1");
-#endif
-    pp->returned_numbers++;
-    return 1;
-} /* read_on_leaf */
-
-static int isamb_pp_forward_on_leaf(ISAMB_PP pp, void *buf, const void *untilbuf)
-{ /* forwards on the current leaf, returns 0 if not found */
-    int cmp;
-    int skips = 0;
-    while (1)
-    {
-        if (!isamb_pp_read_on_leaf(pp, buf))
-            return 0;
-        /* FIXME - this is an extra function call, inline the read? */
-        cmp=(*pp->isamb->method->compare_item)(untilbuf, buf);
-        if (cmp <pp->scope)
-	{  /* cmp<2  found a good one */
-#if ISAMB_DEBUG
-            if (skips)
-                yaz_log(YLOG_DEBUG, "isam_pp_fwd_on_leaf skipped %d items", skips);
-#endif
-            pp->returned_numbers++;
-            return 1;
-        }
-        if (!skips)
-            if (!isamb_pp_on_right_node(pp, pp->level, untilbuf))
-                return 0; /* never mind the rest of this leaf */
-        pp->skipped_numbers++;
-        skips++;
-    }
-} /* forward_on_leaf */
-
-static int isamb_pp_climb_level(ISAMB_PP pp, ISAM_P *pos)
-{ /* climbs higher in the tree, until finds a level with data left */
-  /* returns the node to (consider to) descend to in *pos) */
-    struct ISAMB_block *p = pp->block[pp->level];
-    const char *src;
-#if ISAMB_DEBUG
-    yaz_log(YLOG_DEBUG, "isamb_pp_climb_level starting "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-    assert(pp->level >= 0);
-    assert(p->offset <= p->size);
-    if (pp->level==0)
-    {
-#if ISAMB_DEBUG
-        yaz_log(YLOG_DEBUG, "isamb_pp_climb_level returning 0 at root");
-#endif
-        return 0;
-    }
-    assert(pp->level>0); 
-    close_block(pp->isamb, pp->block[pp->level]);
-    pp->block[pp->level] = 0;
-    (pp->level)--;
-    p = pp->block[pp->level];
-#if ISAMB_DEBUG
-    yaz_log(YLOG_DEBUG, "isamb_pp_climb_level climbed to level %d node %d ofs=%d",
-                    pp->level, p->pos, p->offset);
-#endif
-    assert(!p->leaf);
-    assert(p->offset <= p->size);
-    if (p->offset == p->size)
-    {
-        /* we came from the last pointer, climb on */
-        if (!isamb_pp_climb_level(pp, pos))
-            return 0;
-        p = pp->block[pp->level];
-    }
-    else
-    {
-#if INT_ENCODE
-	char file_item_buf[DST_ITEM_MAX];
-	char *file_item = file_item_buf;
-        ISAMB b = pp->isamb;
-	void *c1 = (*b->method->codec.start)();
-#else
-	zint item_len;
-#endif
-        /* skip the child we just came from */
-#if ISAMB_DEBUG
-        yaz_log(YLOG_DEBUG, "isam_pp_climb_level: skipping lev=%d ofs=%d sz=%d", 
-                        pp->level, p->offset, p->size);
-#endif
-        assert (p->offset < p->size);
-        src = p->bytes + p->offset;
-#if INT_ENCODE
-	(*b->method->codec.decode)(c1, &file_item, &src);
-	(*b->method->codec.stop)(c1);
-#else
-	decode_item_len(&src, &item_len);
-        src += item_len;
-#endif
-        decode_ptr(&src, pos);
-        p->offset = src - (char *)p->bytes;
-            
-    }
-    return 1;
-} /* climb_level */
-
-
-static zint isamb_pp_forward_unode(ISAMB_PP pp, zint pos, const void *untilbuf)
-{ /* scans a upper node until it finds a child <= untilbuf */
-  /* pp points to the key value, as always. pos is the child read from */
-  /* the buffer */
-  /* if all values are too small, returns the last child in the node */
-  /* FIXME - this can be detected, and avoided by looking at the */
-  /* parent node, but that gets messy. Presumably the cost is */
-  /* pretty low anyway */
-    ISAMB b = pp->isamb;
-    struct ISAMB_block *p = pp->block[pp->level];
-    const char *src = p->bytes + p->offset;
-    int cmp;
-    zint nxtpos;
-#if ISAMB_DEBUG
-    int skips = 0;
-    yaz_log(YLOG_DEBUG, "isamb_pp_forward_unode starting "
-                   "at level %d node %d ofs=%di sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-    assert(!p->leaf);
-    assert(p->offset <= p->size);
-    if (p->offset == p->size)
-    {
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward_unode returning at end "
-                   "at level %d node %d ofs=%di sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-        return pos; /* already at the end of it */
-    }
-    while(p->offset < p->size)
-    {
-#if INT_ENCODE
-	char file_item_buf[DST_ITEM_MAX];
-	char *file_item = file_item_buf;
-	void *c1 = (*b->method->codec.start)();
-        (*b->method->codec.decode)(c1, &file_item, &src);
-	(*b->method->codec.stop)(c1);
-	cmp = (*b->method->compare_item)(untilbuf, file_item_buf);
-#else
-	zint item_len;
-        decode_item_len(&src, &item_len);
-        cmp = (*b->method->compare_item)(untilbuf, src);
-        src += item_len;
-#endif
-        decode_ptr(&src, &nxtpos);
-        if (cmp<pp->scope) /* cmp<2 */
-        {
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward_unode returning a hit "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-            return pos;
-        } /* found one */
-        pos = nxtpos;
-        p->offset = src-(char*)p->bytes;
-        (pp->skipped_nodes[pp->maxlevel - pp->level -1])++;
-#if ISAMB_DEBUG
-        skips++;
-#endif
-    }
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward_unode returning at tail "
-                   "at level %d node %d ofs=%d sz=%d skips=%d",
-                    pp->level, p->pos, p->offset, p->size, skips);
-#endif
-    return pos; /* that's the last one in the line */
-    
-} /* forward_unode */
-
-static void isamb_pp_descend_to_leaf(ISAMB_PP pp, ISAM_P pos,
-				     const void *untilbuf)
-{ /* climbs down the tree, from pos, to the leftmost leaf */
-    struct ISAMB_block *p = pp->block[pp->level];
-    const char *src;
-    assert(!p->leaf);
-#if ISAMB_DEBUG
-    yaz_log(YLOG_DEBUG, "isamb_pp_descend_to_leaf "
-                   "starting at lev %d node %d ofs=%d lf=%d u=%p", 
-                   pp->level, p->pos, p->offset, p->leaf, untilbuf);
-#endif
-    if (untilbuf)
-        pos = isamb_pp_forward_unode(pp, pos, untilbuf);
-    ++(pp->level);
-    assert(pos);
-    p = open_block(pp->isamb, pos);
-    pp->block[pp->level] = p;
-    ++(pp->accessed_nodes[pp->maxlevel-pp->level]);
-    ++(pp->no_blocks);
-#if ISAMB_DEBUG
-    yaz_log(YLOG_DEBUG, "isamb_pp_descend_to_leaf "
-                   "got lev %d node %d lf=%d", 
-                   pp->level, p->pos, p->leaf);
-#endif
-    if (p->leaf)
-        return;
-    assert (p->offset==0);
-    src = p->bytes + p->offset;
-    decode_ptr(&src, &pos);
-    p->offset = src-(char*)p->bytes;
-    isamb_pp_descend_to_leaf(pp, pos, untilbuf);
-#if ISAMB_DEBUG
-    yaz_log(YLOG_DEBUG, "isamb_pp_descend_to_leaf "
-                   "returning at lev %d node %d ofs=%d lf=%d", 
-                   pp->level, p->pos, p->offset, p->leaf);
-#endif
-} /* descend_to_leaf */
-
-static int isamb_pp_find_next_leaf(ISAMB_PP pp)
-{ /* finds the next leaf by climbing up and down */
-    ISAM_P pos;
-    if (!isamb_pp_climb_level(pp, &pos))
-        return 0;
-    isamb_pp_descend_to_leaf(pp, pos, 0);
-    return 1;
-}
-
-static int isamb_pp_climb_desc(ISAMB_PP pp,  const void *untilbuf)
-{ /* climbs up and descends to a leaf where values >= *untilbuf are found */
-    ISAM_P pos;
-#if ISAMB_DEBUG
-    struct ISAMB_block *p = pp->block[pp->level];
-    yaz_log(YLOG_DEBUG, "isamb_pp_climb_desc starting "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-    if (!isamb_pp_climb_level(pp, &pos))
-        return 0;
-    /* see if it would pay to climb one higher */
-    if (!isamb_pp_on_right_node(pp, pp->level, untilbuf))
-        if (!isamb_pp_climb_level(pp, &pos))
-            return 0;
-    isamb_pp_descend_to_leaf(pp, pos, untilbuf);
-#if ISAMB_DEBUG
-    p = pp->block[pp->level];
-    yaz_log(YLOG_DEBUG, "isamb_pp_climb_desc done "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-    return 1;
-} /* climb_desc */
-
-int isamb_pp_forward (ISAMB_PP pp, void *buf, const void *untilbuf)
-{
-#if ISAMB_DEBUG
-    struct ISAMB_block *p = pp->block[pp->level];
-    assert(p->leaf);
-    yaz_log(YLOG_DEBUG, "isamb_pp_forward starting "
-                   "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))
-	{
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward (f) returning (A) "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-            return 1;
-        }
-        if (! isamb_pp_climb_desc(pp, untilbuf))
-	{
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward (f) returning notfound (B) "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-            return 0; /* could not find a leaf */
-        }
-        do {
-            if (isamb_pp_forward_on_leaf(pp, buf, untilbuf))
-	    {
-#if ISAMB_DEBUG
-		yaz_log(YLOG_DEBUG, "isamb_pp_forward (f) returning (c) "
-			"at level %d node %d ofs=%d sz=%d",
-			pp->level, p->pos, p->offset, p->size);
-#endif
-                return 1;
-            }
-        } while (isamb_pp_find_next_leaf(pp));
-        return 0; /* could not find at all */
-    }
-    else { /* no untilbuf, a straight read */
-        /* FIXME - this should be moved
-         * directly into the pp_read */
-        /* keeping here now, to keep same
-         * interface as the old fwd */
-        if (isamb_pp_read_on_leaf(pp, buf))
-	{
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward (read) returning (D) "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-            return 1;
-        }
-        if (isamb_pp_find_next_leaf(pp))
-	{
-#if ISAMB_DEBUG
-            yaz_log(YLOG_DEBUG, "isamb_pp_forward (read) returning (E) "
-                   "at level %d node %d ofs=%d sz=%d",
-                    pp->level, p->pos, p->offset, p->size);
-#endif
-            return isamb_pp_read_on_leaf(pp, buf);
-        }
-        else
-            return 0;
-    }
-} /* isam_pp_forward (new version) */
-
 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 */
     assert(total);
     assert(current);
-    
+
     /* if end-of-stream PP may not be leaf */
 
     *total = (double) (pp->block[0]->no_items);
     *current = (double) pp->returned_numbers;
 #if ISAMB_DEBUG
     yaz_log(YLOG_LOG, "isamb_pp_pos returning: cur= %0.1f tot=%0.1f rn="
-	 ZINT_FORMAT, *current, *total, pp->returned_numbers);
+            ZINT_FORMAT, *current, *total, pp->returned_numbers);
 #endif
 }
 
-int isamb_pp_forward2(ISAMB_PP pp, void *buf, const void *untilb)
+int isamb_pp_forward(ISAMB_PP pp, void *buf, const void *untilb)
 {
     char *dst = buf;
     const char *src;
@@ -1906,7 +1528,7 @@ int isamb_pp_forward2(ISAMB_PP pp, void *buf, const void *untilb)
     ISAMB b = pp->isamb;
     if (!p)
         return 0;
-again:
+ again:
     while (p->offset == p->size)
     {
         ISAM_P pos;
@@ -1922,24 +1544,24 @@ again:
         {
             if (pp->level == 0)
                 return 0;
-            close_block (pp->isamb, pp->block[pp->level]);
+            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);
         }
 
 	assert(!p->leaf);
         src = p->bytes + p->offset;
-       
+
 #if INT_ENCODE
 	c1 = (*b->method->codec.start)();
 	(*b->method->codec.decode)(c1, &file_item, &src);
 #else
-        decode_ptr (&src, &item_len);
+        decode_ptr(&src, &item_len);
         src += item_len;
-#endif        
-        decode_ptr (&src, &pos);
+#endif
+        decode_ptr(&src, &pos);
         p->offset = src - (char*) p->bytes;
 
 	src = p->bytes + p->offset;
@@ -1954,18 +1576,18 @@ again:
 	    file_item = file_item_buf;
 	    (*b->method->codec.reset)(c1);
 	    (*b->method->codec.decode)(c1, &file_item, &src);
-	    if ((*b->method->compare_item)(untilb, file_item_buf) <= 1)
+	    if ((*b->method->compare_item)(untilb, file_item_buf) < pp->scope)
 	    {
 		src = src_0;
 		break;
 	    }
 #else
 	    decode_item_len(&src, &item_len);
-	    if ((*b->method->compare_item)(untilb, src) <= 1)
+	    if ((*b->method->compare_item)(untilb, src) < pp->scope)
 		break;
 	    src += item_len;
 #endif
-	    decode_ptr (&src, &pos);
+	    decode_ptr(&src, &pos);
 	    p->offset = src - (char*) p->bytes;
 	}
 
@@ -1973,22 +1595,22 @@ again:
 
         while (1)
         {
-            pp->block[pp->level] = p = open_block (pp->isamb, pos);
+            pp->block[pp->level] = p = open_block(pp->isamb, pos);
 
             pp->total_size += p->size;
             pp->no_blocks++;
-            
-            if (p->leaf) 
+
+            if (p->leaf)
             {
                 break;
             }
-	    
+
             src = p->bytes + p->offset;
 	    while(1)
 	    {
-		decode_ptr (&src, &pos);
+		decode_ptr(&src, &pos);
 		p->offset = src - (char*) p->bytes;
-		
+
 		if (!untilb || p->offset == p->size)
 		    break;
 		assert(p->offset < p->size);
@@ -1997,14 +1619,14 @@ again:
 		file_item = file_item_buf;
 		(*b->method->codec.reset)(c1);
 		(*b->method->codec.decode)(c1, &file_item, &src);
-		if ((*b->method->compare_item)(untilb, file_item_buf) <= 1)
+		if ((*b->method->compare_item)(untilb, file_item_buf) < pp->scope)
 		{
 		    src = src_0;
 		    break;
 		}
 #else
-		decode_ptr (&src, &item_len);
-		if ((*b->method->compare_item)(untilb, src) <= 1)
+		decode_ptr(&src, &item_len);
+		if ((*b->method->compare_item)(untilb, src) <= pp->scope)
 		    break;
 		src += item_len;
 #endif
@@ -2015,19 +1637,20 @@ again:
 	(*b->method->codec.stop)(c1);
 #endif
     }
-    assert (p->offset < p->size);
-    assert (p->leaf);
+    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)
+        if (!untilb || (*pp->isamb->method->compare_item)(untilb, dst0) < pp->scope)
 	    break;
 	dst = dst0;
 	if (p->offset == p->size) goto again;
     }
+    pp->returned_numbers++;
     return 1;
 }
 
@@ -2055,6 +1678,7 @@ void isamb_set_root_ptr(ISAMB b, zint root_ptr)
 /*
  * Local variables:
  * c-basic-offset: 4
+ * c-file-style: "Stroustrup"
  * indent-tabs-mode: nil
  * End:
  * vim: shiftwidth=4 tabstop=8 expandtab